JP5929337B2 - Fuel cell system and control device for fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system and a control device for the fuel cell system.

  As one type of fuel cell system, one shown in Patent Document 1 is known. As shown in FIG. 1 of Patent Document 1, the fuel cell system includes a current sensor 17f that detects a current input from the fuel cell 11 to the power converter 17c, and a power supply line 32 from the power converter 17c. A current sensor 17g for detecting an output current output to the external power load 33 is provided.

  Moreover, what is shown by patent document 2 is known as another form of a fuel cell system. As shown in FIG. 1 of Patent Document 2, the fuel cell system includes an ammeter 42 that detects the output current I of the fuel cell device 2, and includes a protective fuse 31 and a noise removing capacitor 32 of the power conversion device 3. It is provided in series between them.

  It is desirable to be able to determine whether or not the current sensors 17f and 17g and the ammeter 42 described above are abnormal.

  On the other hand, in order to detect a failed current sensor, as shown in FIG. 2 of Patent Document 3, the current sensor is multiplexed in each of the U phase and V phase that are current measurement phases. Sensors 140a, 140b, 141a, 141b are arranged. The control device 115 detects a failure of the current sensor by comparing the current measurement values by a plurality of current sensors in each current detection phase, and at the time of failure detection, a failure detection mode in which a circulating current flows through the current measurement phase. To identify the faulty current sensor.

JP 2009-272158 A JP 2010-192256 A JP 2005-160136 A

  In order to detect abnormalities in the current sensors 17f and 17g and the ammeter 42 of the fuel cell system described in Patent Documents 1 and 2 described above, as described in Patent Document 3 described above, a current sensor is provided at the same location. If two are arranged, a failure of the current sensor can be detected, but the number of current sensors is doubled, resulting in a problem of high cost and large system.

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to determine whether or not a current sensor is abnormal in a fuel cell system without increasing the cost and increasing the size of the system. To do.

In order to solve the above-mentioned problem, the invention of the control device for a fuel cell system according to claim 1 acquires the fuel cell output current value detected by the first current sensor that detects the output current value from the fuel cell. 1 acquisition unit and a second current sensor for detecting an input current value to the power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to an external load A second acquisition unit that acquires the input current value of the power conversion unit detected by the control unit, and a current value that is consumed by an auxiliary device stored in advance in the storage unit and that is within a predetermined range Any of the third acquisition unit, the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the consumption current value acquired by the third acquisition unit Select two The result of adding or subtracting the two values is compared with the remaining one, and whether or not at least one of the first current sensor and the second current sensor is abnormal based on the comparison result A first determination unit that determines the output current value, a fourth acquisition unit that acquires a power conversion unit output current value detected by a third current sensor that detects an output current value from the power conversion unit, and a storage unit that is stored in advance. A fifth acquisition unit that acquires a current value corresponding to the conversion loss in the power conversion unit that is within a predetermined range, and a first from the power conversion unit input current value acquired by the second acquisition unit Calculated by the first average value calculating unit, the effective value calculating unit calculating the effective value from the output current value of the power conversion unit acquired by the fourth acquiring unit, and the first average value calculating unit. First of the power converter input current value Select any two of the average value, the effective value of the output current value of the power conversion unit calculated by the effective value calculation unit, and the loss current value acquired by the fifth acquisition unit, and the addition result of the two values Or a second determination unit that compares the subtraction result with the remaining one and determines whether or not at least one of the second current sensor and the third current sensor is abnormal based on the comparison result; It is equipped with.

The invention according to claim 2, in claim 1, the first determination unit determines that at least one of the first current sensor and the second current sensor is in an abnormal state is abnormal, the second determination unit A first specifying unit that specifies that the first current sensor is abnormal when it is determined that the second current sensor and the third current sensor are normal is further provided.

According to a third aspect of the present invention, there is provided a first acquisition unit that acquires a fuel cell output current value detected by a first current sensor that detects an output current value from a fuel cell, and at least a complement of output power of the fuel cell. The power conversion unit input current value detected by the second current sensor that detects the input current value to the power conversion unit that inputs the remaining power after being supplied to the machine, converts it, and outputs it to the external load is acquired. 2 acquisition unit, a third acquisition unit that acquires a current value consumed by an auxiliary machine stored in advance in the storage unit and within a predetermined range, and acquired by the first acquisition unit Select any two of the fuel cell output current value, the power conversion unit input current value acquired by the second acquisition unit, and the current consumption value acquired by the third acquisition unit, and the result of adding the two values Or the subtraction result and the rest Bract compares a first determination unit configured to determine whether at least one is in an abnormal state is abnormal in the first current sensor and the second current sensor based on the comparison result, output from the power conversion unit A power acquisition unit that acquires a power conversion unit output current value detected by a third current sensor that detects a current value; a current value that is stored in advance in the storage unit and consumed by the auxiliary device; and a power conversion unit A sixth obtaining unit that obtains a current value obtained by adding the current values corresponding to the conversion losses of the first and second components, and a second average from the fuel cell output current value obtained by the first obtaining unit. A second average value calculating unit that calculates a value; an effective value calculating unit that calculates an effective value from the output current value of the power converter acquired by the fourth acquiring unit; and a fuel cell calculated by the second average value calculating unit 2nd average and effective value of output current value Select any two of the effective value of the power conversion unit output current value calculated by the output unit and the current value acquired by the sixth acquisition unit, the addition result or subtraction result of the two values and the remaining And a third determination unit that determines whether or not at least one of the first current sensor and the third current sensor is abnormal based on the comparison result.

According to a fourth aspect of the present invention, in the third aspect , the first determination unit determines that at least one of the first current sensor and the second current sensor is in an abnormal state, and the third determination unit When it determines with a 1st current sensor and a 3rd current sensor being normal, the 2nd specific | specification part which specifies that a 2nd current sensor is abnormal is further provided.

According to a fifth aspect of the present invention, there is provided a first acquisition unit that acquires a fuel cell output current value detected by a first current sensor that detects an output current value from a fuel cell, and at least a complement of output power of the fuel cell. The power conversion unit input current value detected by the second current sensor that detects the input current value to the power conversion unit that inputs the remaining power after being supplied to the machine, converts it, and outputs it to the external load is acquired. 2 acquisition unit, a third acquisition unit that acquires a current value consumed by an auxiliary machine stored in advance in the storage unit and within a predetermined range, and acquired by the first acquisition unit Select any two of the fuel cell output current value, the power conversion unit input current value acquired by the second acquisition unit, and the current consumption value acquired by the third acquisition unit, and the result of adding the two values Or the subtraction result and the rest Bract compares a first determination unit configured to determine whether at least one is in an abnormal state is abnormal in the first current sensor and the second current sensor based on the comparison result, output from the power conversion unit A current value corresponding to a conversion loss in a power conversion unit stored in advance in a storage unit, a fourth acquisition unit that acquires a power conversion unit output current value detected by a third current sensor that detects a current value, A fifth acquisition unit that acquires a loss current value within a predetermined range, and a current value that is stored in advance in the storage unit and consumed by the auxiliary device and a current value corresponding to the conversion loss in the power conversion unit are added. A first acquisition unit that calculates the first average value from the input current value acquired by the power acquisition unit acquired by the sixth acquisition unit and the power acquisition unit acquired by the second acquisition unit And the fuel cell output acquired by the first acquisition unit A second average value calculating unit that calculates a second average value from the current value, an effective value calculating unit that calculates an effective value from the output current value of the power converter acquired by the fourth acquiring unit, and a first average value calculating Of the first average value of the input current value of the power conversion unit calculated by the unit, the effective value of the output current value of the power conversion unit calculated by the effective value calculation unit, and the loss current value acquired by the fifth acquisition unit Select any two, compare the addition or subtraction result of the two values with the remaining one, and at least one of the second current sensor and the third current sensor is abnormal based on the comparison result The second determination unit that determines whether or not the state is abnormal, the second average value of the fuel cell output current value calculated by the second average value calculation unit, the power conversion unit output calculated by the effective value calculation unit RMS value of current value, and Select any two of the current values acquired by the sixth acquisition unit, compare the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the first current sensor and A third determination unit that determines whether or not at least one of the third current sensors is in an abnormal state.

According to a sixth aspect of the present invention, in the fifth aspect , the first determination unit determines that the first current sensor and the second current sensor are normal, and the second determination unit determines that the second current sensor and the third current are normal. It is determined that at least one of the sensors is in an abnormal state, or / and the third determination unit determines that at least one of the first current sensor and the third current sensor is in an abnormal state A third specifying unit for specifying that the third current sensor is abnormal.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the first determination unit is acquired by the fuel cell output current value acquired by the first acquisition unit and the second acquisition unit. When the other possible range is calculated from one of the power converter input current values and the current consumption value acquired by the third acquisition unit, and the other of the acquired values is outside the calculated possible range Determines that the first current sensor or / and the second current sensor is in an abnormal state, and if the other of the acquired values is within the calculated possible range, the first current sensor It is determined that the sensor and the second current sensor are normal.
According to an eighth aspect of the present invention, in any one of the first to sixth aspects, the first determination unit is acquired by the fuel cell output current value acquired by the first acquisition unit and the second acquisition unit. When the current value difference with the power conversion unit input current value is outside the predetermined range of the current consumption value acquired by the third acquisition unit, the first current sensor and / or the second current sensor is abnormal On the other hand, when the current value difference is within the predetermined range, it is determined that the first current sensor and the second current sensor are normal.
An invention of a fuel cell system according to a ninth aspect includes the control device for the fuel cell system according to any one of the first to eighth aspects.

In the invention according to claim 1 configured as described above, the first acquisition unit acquires the fuel cell output current value detected by the first current sensor that detects the output current value from the fuel cell. The second acquisition unit detects the input current value to the power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to the external load. The power converter input current value detected by the sensor is acquired. The third acquisition unit acquires a current value that is consumed by an auxiliary machine stored in advance in the storage unit and that is within a predetermined range. The first determination unit includes the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the current consumption value acquired by the third acquisition unit. Any two of them are selected, the result of addition or subtraction of these two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result. It is determined whether or not there is a certain abnormal state. Accordingly, at least one of the first current sensor and the second current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.
Further, the fourth acquisition unit acquires the power conversion unit output current value detected by the third current sensor that detects the output current value from the power conversion unit. The fifth acquisition unit acquires a current value corresponding to the conversion loss in the power conversion unit stored in advance in the storage unit and is within a predetermined range. The first average value calculation unit calculates a first average value from the power conversion unit input current value acquired by the second acquisition unit. The effective value calculation unit calculates an effective value from the power conversion unit output current value acquired by the fourth acquisition unit. The second determination unit includes a first average value of the power conversion unit input current value calculated by the first average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and Select any two of the loss current values acquired by the fifth acquisition unit, compare the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the second current sensor Whether or not at least one of the third current sensors is abnormal is determined. Accordingly, at least one of the second current sensor and the third current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.

In the invention according to claim 2 configured as described above, in claim 1 , the first determination unit determines that at least one of the first current sensor and the second current sensor is in an abnormal state. The first determining unit further specifies that the first current sensor is abnormal when the second determining unit determines that the second current sensor and the third current sensor are normal. As a result, it can be accurately and reliably determined whether or not the first current sensor is normal.

In the invention which concerns on Claim 3 comprised as mentioned above, a 1st acquisition part acquires the fuel cell output current value detected by the 1st current sensor which detects the output current value from a fuel cell. The second acquisition unit detects the input current value to the power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to the external load. The power converter input current value detected by the sensor is acquired. The third acquisition unit acquires a current value that is consumed by an auxiliary machine stored in advance in the storage unit and that is within a predetermined range. The first determination unit includes the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the current consumption value acquired by the third acquisition unit. Any two of them are selected, the result of addition or subtraction of these two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result. It is determined whether or not there is a certain abnormal state. Accordingly, at least one of the first current sensor and the second current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.
Further, the fourth acquisition unit acquires the power conversion unit output current value detected by the third current sensor that detects the output current value from the power conversion unit. The sixth acquisition unit is stored in advance in the storage unit, and is a current value obtained by adding the current value consumed by the auxiliary machine and the current value corresponding to the conversion loss in the power conversion unit, and is within a predetermined range. Get things. The second average value calculation unit calculates a second average value from the fuel cell output current value acquired by the first acquisition unit. The effective value calculation unit calculates an effective value from the power conversion unit output current value acquired by the fourth acquisition unit. The third determination unit includes a second average value of the fuel cell output current value calculated by the second average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and a first 6 selects any two of the current values acquired by the acquisition unit, compares the addition result or subtraction result of the two values with the remaining one, and determines the first current sensor and the first current based on the comparison result. It is determined whether or not at least one of the three current sensors is in an abnormal state. Accordingly, at least one of the first current sensor and the third current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.

In the invention according to claim 4 configured as described above, in claim 3 , the first determination unit determines that at least one of the first current sensor and the second current sensor is in an abnormal state. The second determination unit further includes a second specifying unit that specifies that the second current sensor is abnormal when the third determination unit determines that the first current sensor and the third current sensor are normal. Thereby, it can be determined correctly and reliably whether the 2nd current sensor is normal.

In the invention which concerns on Claim 5 comprised as mentioned above, a 1st acquisition part acquires the fuel cell output current value detected by the 1st current sensor which detects the output current value from a fuel cell. The second acquisition unit detects the input current value to the power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to the external load. The power converter input current value detected by the sensor is acquired. The third acquisition unit acquires a current value that is consumed by an auxiliary machine stored in advance in the storage unit and that is within a predetermined range. The first determination unit includes the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the current consumption value acquired by the third acquisition unit. Any two of them are selected, the result of addition or subtraction of these two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result. It is determined whether or not there is a certain abnormal state. Accordingly, at least one of the first current sensor and the second current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.
Further, the fourth acquisition unit acquires the power conversion unit output current value detected by the third current sensor that detects the output current value from the power conversion unit. The fifth acquisition unit acquires a current value corresponding to the conversion loss in the power conversion unit stored in advance in the storage unit and is within a predetermined range. The sixth acquisition unit is stored in advance in the storage unit, and is a current value obtained by adding the current value consumed by the auxiliary machine and the current value corresponding to the conversion loss in the power conversion unit, and is within a predetermined range. Get things. The first average value calculation unit calculates a first average value from the power conversion unit input current value acquired by the second acquisition unit. The second average value calculation unit calculates a second average value from the fuel cell output current value acquired by the first acquisition unit. The effective value calculation unit calculates an effective value from the power conversion unit output current value acquired by the fourth acquisition unit. The second determination unit includes a first average value of the power conversion unit input current value calculated by the first average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and a fifth Select any two of the loss current values acquired by the acquisition unit, compare the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the second current sensor and the second It is determined whether or not at least one of the three current sensors is in an abnormal state. The third determination unit includes a second average value of the fuel cell output current value calculated by the second average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and a first 6 selects any two of the current values acquired by the acquisition unit, compares the addition result or subtraction result of the two values with the remaining one, and determines the first current sensor and the first current based on the comparison result. It is determined whether or not at least one of the three current sensors is in an abnormal state. Accordingly, at least one of the first current sensor to the third current sensor is abnormal without providing another current sensor for detecting the abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not there is a certain abnormal state.

In the invention according to claim 6 configured as described above, in claim 5 , the first determination unit determines that the first current sensor and the second current sensor are normal, and the second determination unit is the second. It is determined that at least one of the current sensor and the third current sensor is in an abnormal state, and / or the third determination unit is abnormal in which at least one of the first current sensor and the third current sensor is abnormal When it determines with it being in a state, it further has the 3rd specific part which specifies that the 3rd current sensor is abnormal. As a result, it is possible to accurately and reliably determine whether or not the third current sensor is normal.

In the invention according to claim 7 configured as described above, in any one of claims 1 to 6, the first determination unit includes the fuel cell output current value acquired by the first acquisition unit and the first determination unit. The other possible range is calculated from one of the power conversion unit input current values acquired by the 2 acquisition unit and the current consumption value acquired by the third acquisition unit, and the other of the acquired values is calculated When it is outside the range, it is determined that the first current sensor and / or the second current sensor is in an abnormal state, and the other of the acquired values is within the calculated possible range. Has determined that the first current sensor and the second current sensor are normal. Thereby, it is possible to reliably and accurately determine whether or not the first current sensor and the second current sensor are normal.
In the invention according to claim 8 configured as described above, in any one of claims 1 to 6, the first determination unit is configured to calculate the fuel cell output current value acquired by the first acquisition unit and When the current value difference from the power conversion unit input current value acquired by the 2 acquisition unit is outside the predetermined range of the current consumption value acquired by the third acquisition unit, the first current sensor and / or the second current When it is determined that the sensor is in an abnormal state, and the current value difference is within a predetermined range, it is determined that the first current sensor and the second current sensor are normal. Thereby, it is possible to reliably and accurately determine whether or not the first current sensor and the second current sensor are normal.
The invention according to claim 9 configured as described above includes the control device for the fuel cell system according to any one of claims 1 to 8 . Thereby, the fuel cell system which has the effect | action and effect of Claim 1 thru | or Claim 8 mentioned above can be provided.

It is a schematic diagram showing an outline of one embodiment of a fuel cell system according to the present invention. It is a flowchart of the control program (1st Example) performed with the control apparatus shown in FIG. It is a figure which shows correlation with an electric power converter part input electric current value and auxiliary machine consumption electric current value. It is a flowchart of the control program (2nd Example) performed with the control apparatus shown in FIG. It is a flowchart of the control program (3rd Example) performed with the control apparatus shown in FIG. It is a flowchart of the control program (4th Example) performed with the control apparatus shown in FIG. It is a figure which shows the correlation of a power converter output current value and a loss current value. It is a figure which shows the correlation of a power converter output current value and a power converter input current value. It is a flowchart of the control program (5th Example) performed with the control apparatus shown in FIG. It is a flowchart of the control program (6th Example) performed with the control apparatus shown in FIG. It is a flowchart of the control program (7th Example) performed with the control apparatus shown in FIG. It is a flowchart of the control program (it specifies that the 1st-3rd current sensor is abnormal) performed with the control apparatus shown in FIG. It is a table which shows the relationship between the state of a 1st-3rd current sensor, and the determination result of a 1st-3rd determination part.

  Hereinafter, an embodiment of a fuel cell system according to the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of the fuel cell system. The fuel cell system includes a fuel cell module 11, a system power supply 12, a power supply line 13, an auxiliary machine 15, an inverter device 16, a fuel cell system control device (hereinafter referred to as a control device) 17, and a hot water tank 21. Has been.

  The fuel cell module 11 includes a casing 11a, an evaporation unit 11b, a reforming unit 11c, and a fuel cell 11d. An evaporation unit 11b, a reforming unit 11c, and a fuel cell 11d are disposed in the casing 11a. At this time, the evaporation unit 11b and the reforming unit 11c are disposed above the fuel cell 11d.

  The evaporation unit 11b is heated by a combustion gas, which will be described later, to evaporate the supplied reforming water to generate water vapor, and to preheat the supplied reforming raw material. The evaporating unit 11b mixes the steam generated in this way and the preheated reforming raw material and supplies them to the reforming unit 11c. Examples of the reforming raw material include natural gas, gas fuel for reforming such as LPG, and liquid fuel for reforming such as kerosene, gasoline, and methanol. In the present embodiment, description will be made on natural gas.

  The evaporating unit 11b is supplied with reforming water from a water tank (not shown) by a reforming water pump 15a and with reforming raw material from a fuel supply source (not shown) by a raw material pump 15b. Yes.

  The reforming unit 11c is heated by a combustion gas described later and supplied with heat necessary for the steam reforming reaction, so that the reformed gas is generated from the mixed gas (reforming raw material, steam) supplied from the evaporation unit 11b. Is generated and derived. The reforming part 11c is filled with a catalyst (for example, Ru or Ni-based catalyst), and the mixed gas reacts and is reformed by the catalyst to generate hydrogen gas and carbon monoxide gas (so-called so-called). Steam reforming reaction). At the same time, a so-called carbon monoxide shift reaction occurs in which carbon monoxide generated in the steam reforming reaction reacts with steam to transform into hydrogen gas and carbon dioxide. These generated gases (so-called reformed gas) are led out to the fuel electrode of the fuel cell 11d. The reformed gas contains hydrogen, carbon monoxide, carbon dioxide, water vapor, and unreformed natural gas (methane gas). The steam reforming reaction is an endothermic reaction, and the carbon monoxide shift reaction is an exothermic reaction.

  The fuel cell 11d is configured by laminating a fuel electrode, an air electrode (oxidant electrode), and a plurality of cells (not shown) made of an electrolyte interposed between the two electrodes. The fuel cell of the present embodiment is a solid oxide fuel cell, and uses zirconium oxide, which is a kind of solid oxide, as an electrolyte. Hydrogen, carbon monoxide, methane gas, or the like is supplied as a fuel to the fuel electrode of the fuel cell 11d. The operating temperature is, for example, about 400 to 1000 ° C. On the fuel electrode side of the cell, a fuel flow path (not shown) through which the reformed gas as the fuel flows is formed. An air flow path (not shown) through which air (cathode air) as an oxidant gas flows is formed on the air electrode side of the cell. Cathode air is supplied to the air flow path by a cathode air blower 15c (or a cathode air pump).

In the fuel cell 11d, power generation is performed by the fuel supplied to the fuel electrode and the oxidant gas supplied to the air electrode. That is, the reaction shown in Chemical Formula 1 and Chemical Formula 2 below occurs at the fuel electrode, and the reaction shown in Chemical Formula 3 below occurs at the air electrode. That is, oxide ions (O ²⁻ ) generated at the air electrode permeate the electrolyte and react with hydrogen at the fuel electrode to generate electrical energy. Therefore, the reformed gas and the oxidant gas (air) that have not been used for power generation are derived from the fuel channel and the air channel.
(Chemical formula 1)
H ₂ + O ²⁻ → H ₂ O + 2e ⁻
(Chemical formula 2)
CO + O ²⁻ → CO ₂ + 2e ⁻
(Chemical formula 3)
1 / 2O ₂ + 2e ⁻ → O ²⁻

  The reformed gas derived from the fuel flow path and the air flow path and not used for power generation is used for power generation in the combustion space 11e between the fuel cell 11d and the evaporation section 11b (reforming section 11c). The oxidant gas (air) that has not existed is combusted, and the evaporation section 11b and the reforming section 11c are heated by the combustion gas. Furthermore, the inside of the fuel cell module 11 is heated to the operating temperature. Thereafter, the combustion gas is exhausted out of the fuel cell module 11 from an outlet 11a1 provided at the lower portion of the casing 11a from which combustion exhaust gas is derived.

  The system power supply (or commercial power supply) 12 supplies power (AC power) to the external load 14 via a power supply line 13 connected to the system power supply 12. The fuel cell 11 d is connected to the power supply line 13 via the inverter device 16. The external load 14 is a power load disposed outside the fuel cell system, and is, for example, a home appliance such as a television disposed in a home.

  The power supply line 13 is provided with a power measuring device 13 a that detects power input / output and the amount of power with respect to the system power supply 12, and the detection result is output to the control device 17.

  Auxiliary machine 15, which is one of internal loads, is connected to motor-driven pumps 15a and 15b, electromagnetic valves (not shown), and fuel cell 11d for supplying reforming water and reforming raw material to evaporator 11b. A motor-driven blower 15c for supplying cathode air, an electromagnetic valve (not shown), and the like are included. The auxiliary machine 15 is driven by a DC voltage, and the driving voltage is supplied from the auxiliary machine DC / DC converter 16e. The auxiliary machine 15 is for supplying fuel (reforming raw material) and oxidant gas (cathode air) to the fuel cell 11d, and for operating the fuel cell system. The internal load is a power load arranged in the fuel cell system, and includes an auxiliary machine 15 and a control device 17.

  The inverter device 16 converts the DC voltage output from the fuel cell 11d into a predetermined AC voltage and outputs it to the power supply line 13 connected to the system power supply 12, and the AC voltage from the power supply line 13 to a predetermined value. A function of converting to DC voltage and outputting to auxiliary machine 15 and control device 17 (internal load), and a function of converting DC voltage from fuel cell 11d to a predetermined DC voltage and outputting to auxiliary machine 15 and control device 17 And have.

  Specifically, the inverter device 16 includes a DC / DC converter 16a, a DC / AC inverter 16b, an AC / DC converter 16c, a control DC / DC converter 16d, and an auxiliary DC / DC converter 16e. ing.

  The DC / DC converter 16a converts a DC voltage (for example, 40V) output from the fuel cell 11d into a predetermined DC voltage (for example, 350V). The DC / AC inverter 16b converts the DC voltage output from the DC / DC converter 16a into an AC voltage (for example, 200V) and outputs it to the power supply line 13.

  The DC / DC converter 16a and the DC / AC inverter 16b are provided in series on the third power supply line L3. One end of the third power supply line L3 is connected to a portion on the first power supply line L1 between the fuel cell 11d, the control DC / DC converter 16d, and the auxiliary DC / DC converter 16e, The other end is on the second power supply line L2 and connected to a portion between the system power supply 12 and the AC / DC converter 16c.

  The AC / DC converter 16c is provided in parallel with a circuit including the DC / DC converter 16a and the DC / AC inverter 16b between the power supply line 13 and the auxiliary machine 15. The AC / DC converter 16c is provided on the second power supply line L2. One end of the second power supply line L2 is connected to the power supply line 13 connected to the system power supply 12, and the other end is on the first power supply line L1, and the fuel cell 11d and the control DC / DC converter 16d. And a portion between the auxiliary device DC / DC converter 16e.

  The AC / DC converter 16c receives AC power (AC voltage) output from the system power supply 12 and converts it into DC power (DC voltage) during normal operation as well as during start-up and stop operations. Output to the DC / DC converter 16d for auxiliary use and the DC / DC converter 16e for auxiliary machinery.

  The control DC / DC converter 16d receives a DC voltage (DC power) from the fuel cell 11d or the AC / DC converter 16c, converts the DC voltage (DC power) into a predetermined DC voltage (DC power, for example, 5V), and supplies the control device 17 with the DC voltage. It is supplied as a power supply voltage.

  The auxiliary machine DC / DC converter 16e receives the direct current voltage (direct current power) from the fuel cell 11d or the AC / DC converter 16c and converts it into a predetermined direct current voltage (direct current power, for example, 24V) to obtain the auxiliary equipment 15 Is supplied as a power supply voltage. The auxiliary DC / DC converter 16 e is connected to the control device 17 and controlled to be driven / stopped by a command from the control device 17. For example, the operation of the auxiliary DC / DC converter 16e is stopped by a stop command from the control device 17 during standby. Thereby, standby power can be suppressed small by stopping DC / DC converter 16e for auxiliary machines at the time of standby.

  The control DC / DC converter 16d and the auxiliary DC / DC converter 16e are provided on the first power supply line L1. One end of the first power supply line L1 is connected to the fuel cell 11d, and the other end is connected to the control device 17 and the auxiliary machine 15. The other end is divided into two, and a control DC / DC converter 16d and an auxiliary DC / DC converter 16e are provided at each branch. The first power supply line L1 supplies DC power output from the fuel cell 11d to the auxiliary machine 15 and the control device 17.

  On the first power supply line L1, a first rectifying element 16f is provided on the fuel cell 11d side from the junction with the second power supply line L2. Specifically, the first rectifying element 16f is provided at a portion between the junction point with the second power supply line L2 and the junction point with the third power supply line L3. The first rectifying element 16f allows only a current flowing from the fuel cell 11d toward the control DC / DC converter 16d and the auxiliary DC / DC converter 16e. In the present embodiment, the first rectifying element is constituted by a diode, for example.

  A second rectifying element 16g is provided on the second power supply line L2. Specifically, the second rectifying element 16g is provided in a portion between the AC / DC converter 16c and the junction of the first power supply line L1. The second rectifying element 16g allows only a current flowing from the AC / DC converter 16c toward the first power supply line L1.

  Further, on the first power supply line L1, a first switch 16h is provided on the fuel cell 11d side from the junction with the second power supply line L2. The first switch 16h shuts off the fuel cell 11d, the control DC / DC converter 16d, and the auxiliary DC / DC converter 16e during start-up operation and stop operation according to an instruction from the control device 17, and It is a switch that communicates during operation.

  The second switch 16i is disposed between the DC / AC inverter 16b and the system power supply 12 (or power supply line 13). Specifically, the second switch 16i is provided on the third power supply line L3 and between the DC / AC inverter 16b and the junction of the second power supply line. The DC / AC inverter 16b and the system power supply 12 are communicated and disconnected according to instructions from the control device 17. When determining that the system power supply 12 is in a power failure state, the control device 17 switches the second switch 16i to an open state, and switches the second switch 16i to a closed state when the system power supply 12 is not in a power failure state.

  A first current sensor 16j is provided on the first power supply line L1. The first current sensor 16j measures (detects) the current value (output current value) of the current (DC current) output from the fuel cell 11d, and transmits the measurement result to the control device 17. ing. The first current sensor 16j includes a resistance for measurement, and is configured to measure a current by measuring a voltage of the resistance. The first current sensor 16j may be of a type that includes a hall element.

  A second current sensor 16k and a third current sensor 16l (16 L) are provided on the third power supply line L3. The second current sensor 16k measures (detects) the current value (input current value) of the current (direct current) input to the DC / DC converter 16a, and transmits the measurement result to the control device 17. It has become. The second current sensor 16k receives at least the remaining power after being supplied to the auxiliary machine 15 from the output power of the fuel cell 11d, converts it, and outputs it to the external load 14 (DC / DC in this embodiment). This is a power conversion unit composed of a DC converter 16a and an AC / DC inverter 16b. The third current sensor 16l measures (detects) the current value (output current value) of the current (alternating current) output from the AC / DC inverter 16b, and transmits the measurement result to the control device 17. It has become.

  The control device 17 collectively performs overall control of the fuel cell system, and controls the driving of the auxiliary machine 15 and the driving of the inverter device 16. The control device 17 includes a microcomputer (not shown), and the microcomputer includes an input / output interface, a CPU, a RAM, and a ROM (all not shown) connected via a bus. The CPU is operating the fuel cell system. The RAM temporarily stores variables necessary for executing the program, and the ROM stores the program. The control device 17 is a control microcomputer (control microcomputer) that controls the auxiliary machine 15.

  The controller 17 is always supplied with a voltage during standby and during operation (including start-up operation, steady operation (power generation operation), and stop operation). The start-up operation is from the start command to the start of power generation, and the stop control is from the stop command to the system stop. The standby state is a power generation stop state of the fuel cell system, and is a state waiting for a power generation instruction (such as turning on a start switch).

  The hot water storage tank 21 stores hot water heated by the exhaust heat of the fuel cell 11d. A heat medium circulation path 21a is provided between the hot water storage tank 21 and the fuel cell 11d, and the heat medium circulation path 21a circulates the heat medium recovered from the exhaust heat of the fuel cell 11d by a pump (not shown). . The hot water stored in the hot water tank 21 is heated by exchanging heat with the heat medium.

  The fuel cell system includes a storage unit 18 that is electrically connected to the control device 17. The storage unit 18 stores a map, a table, an arithmetic expression, and the like that indicate the correlation between the power conversion unit input current value and the auxiliary machine consumption current value, which will be described later. The storage unit 18 may be provided in the control device 17.

  Next, the abnormality determination operation of the first to third current sensors 16j to 16l in the fuel cell system described above will be described.

(First and second current sensors)
First, the first current sensor 16j and the second current sensor 16k will be described with reference to three examples.
First, the power converter input current value Ib is added to or subtracted from the current value consumed by the auxiliary machine 15 and within a predetermined range Ih (hereinafter referred to as auxiliary machine current consumption value). A case (first embodiment) where the result obtained is compared with the fuel cell output current value Ia will be described with reference to FIG.

  When a start switch (not shown) is turned on (or the start is automatically started when the start start time set in advance by the user is reached), the control device 17 is a program corresponding to the flowchart shown in FIG. Start running. This program is executed every predetermined short time.

  In step 102, the control device 17 acquires the fuel cell output current value Ia detected by the first current sensor 16j (first acquisition unit). In step 104, the control device 17 acquires the power conversion unit input current value Ib detected by the second current sensor 16k (second acquisition unit).

  In step 106, the control device 17 acquires the auxiliary machine consumption current value Ih stored in advance in the storage unit 18 (third acquisition unit). The acquired auxiliary machine consumption current value Ih may be shown on a map or may be a predetermined constant value. The auxiliary machine consumption current value Ih represents the current difference between the fuel cell output current value Ia and the power converter input current value Ib. As shown in FIG. 3, the auxiliary machine consumption current value Ih is correlated with the power conversion unit input current value Ib, and the auxiliary machine consumption current value Ih increases as the power conversion unit input power value Ib increases. .

  In steps 108 to 112, the control device 17 determines the power conversion unit input current value Ib acquired in step 104 (second acquisition unit) and the auxiliary machine consumption current value Ih acquired in step 106 (third acquisition unit). Then, a possible range of the fuel cell output current value Ia acquired by step 102 (first acquisition unit) is calculated.

  Specifically, in step 108, the control device 17 calculates the auxiliary machine consumption current value Ih (fuel cell output current value Ia and power conversion unit input) from the power conversion unit input current value Ib and the map shown in FIG. The upper limit value and the lower limit value of the current difference from the current value Ib are calculated. For example, when the power conversion unit input current value Ib is Ib1, the upper limit value of the auxiliary machine consumption current value Ih is Ih1max, the lower limit value of the auxiliary machine consumption current value Ih is Ih1min, and the power conversion unit input current value Ib Is Ib2, the upper limit value of the auxiliary machine consumption current value Ih is Ih2max, and the lower limit value of the auxiliary machine consumption current value Ih is Ih2min.

  In step 110, the controller 17 adds the acquired power conversion unit input current value Ib and the upper limit value of the auxiliary machine consumption current value Ih calculated in step 108 to calculate the upper limit value threshold value of the fuel cell output current value Ia. To do. In step 112, the control device 17 adds the acquired power conversion unit input current value Ib and the lower limit value of the auxiliary machine consumption current value Ih calculated in step 108 to calculate the lower limit threshold value of the fuel cell output current value Ia. To do. The range from the upper limit threshold value to the lower limit threshold value of the fuel cell output current value Ia calculated in this way is a possible range of the acquired fuel cell output current value Ia.

  When the acquired fuel cell output current value Ia is outside the calculated range, that is, outside the range from the upper limit threshold value to the lower limit value threshold value of the fuel cell output current value Ia, in steps 114 to 124 Is determined to be in an abnormal state in which the first current sensor 16j and / or the second current sensor 16k is abnormal, while the acquired fuel cell output current value Ia is within the calculated possible range. , It is determined that the first current sensor 16j and the second current sensor 16k are normal.

  Specifically, in step 114, the control device 17 determines that the acquired fuel cell output current value Ia is greater than the calculated upper limit threshold value of the fuel cell output current value Ia or the acquired fuel cell output current. It is determined whether the value Ia is smaller than the lower limit threshold value of the calculated fuel cell output current value Ia.

  When the acquired fuel cell output current value Ia is within the calculated possible range, that is, within the range from the upper limit threshold value to the lower limit threshold value of the fuel cell output current value Ia, the control device 17 performs step 114. The determination is “NO” and the program proceeds to step 116. In step 116, the control device 17 clears the count of an elapsed time timer, which will be described later, and in step 118, detects that the first current sensor 16j and the second current sensor 16k are normal (determines that they are normal). ).

  If the obtained fuel cell output current value Ia is outside the calculated range, that is, outside the range from the upper limit threshold value to the lower limit threshold value of the fuel cell output current value Ia, the control device 17 performs step 114. The determination is “YES” and the program proceeds to step 120. In step 120, the controller 17 continues the state where the acquired fuel cell output current value Ia is out of the calculated range, that is, out of the range from the upper limit threshold to the lower limit threshold of the fuel cell output current value Ia. The elapsed time timer indicating the elapsed time is counted up.

  Until the elapsed time timer exceeds a threshold value (for example, 5 seconds), that is, when the abnormal state in which the acquired fuel cell output current value Ia is out of the calculated range does not continue for the threshold time or longer, the control device 17 In step 122, “NO” is determined, and this program is temporarily ended (the processing after step 102 is executed after a predetermined short time has elapsed). The threshold value is preferably set to a time that can prevent erroneous determination.

When the elapsed time timer becomes equal to or greater than a threshold (for example, 5 seconds), that is, when an abnormal state in which the acquired fuel cell output current value Ia is out of the calculated range continues for the threshold time or longer, the control device 17 In step 122, “YES” is determined, and the program proceeds to step 124. In step 124, the control device 17 detects that the first current sensor 16j and / or the second current sensor 16k is in an abnormal state (determines that it is in an abnormal state). In step 124, it cannot be specified which of the first current sensor 16j and the second current sensor 16k has failed.
The above-described steps 108 to 114 and 118 and 124 are the first determination unit.

  Here, the reason why the abnormality can be determined will be described. The output power from the fuel cell 11d is supplied to and consumed by the control DC / DC converter 16d, the control device 17, the auxiliary DC / DC converter 16e, and the auxiliary 15 via the first power supply line L1. At the same time, it is supplied to and consumed by the DC / DC converter 16a, the DC / AC inverter 16b, and the external load 14 via the third power supply line L3. In other words, the current difference between the fuel cell output current value Ia detected by the first current sensor 16j and the power converter input current value Ib detected by the second current sensor 16k is the control DC / DC converter 16d, the control device 17, It is equal to the auxiliary machine consumption current supplied to and consumed by the auxiliary DC / DC converter 16e and the auxiliary machine 15.

  Therefore, when both the first current sensor 16j and the second current sensor 16k are normal, the fuel cell output current value Ia detected by the first current sensor 16j and the fuel cell output current detected by the first current sensor 16j. The current difference from the value Ia is within a predetermined range. On the other hand, when at least one of the first current sensor 16j and the second current sensor 16k is abnormal, the fuel cell output current value Ia detected by the first current sensor 16j and the fuel cell output detected by the first current sensor 16j. The current difference from the current value Ia is outside the predetermined range.

  Note that the predetermined range is a range that can cover all operation modes during start-up operation, steady operation, stop operation, standby operation, and emergency stop of the fuel cell system. Can be executed in all operating modes. It should be noted that a predetermined range corresponding to each mode may be set and executed by a predetermined range corresponding to each mode.

  Second, referring to FIG. 4 for a case where the result of adding or subtracting the fuel cell output current value Ia and the auxiliary machine consumption current value Ih is compared with the power converter input current value Ib (second embodiment). I will explain. In the first embodiment described above, it is determined whether or not the obtained fuel cell output current value Ia is within the calculated possible range, whereas in the second embodiment, the obtained value is obtained. The difference is that it is determined whether or not the power converter input current value Ib is within the calculated range. The same processes as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

Specifically, the process of steps 140 to 146 is performed instead of the process of steps 108 to 114 of the first embodiment.
In steps 140 to 144, the control device 17 determines the fuel cell output current value Ia acquired in step 102 (first acquisition unit) and the auxiliary machine consumption current value Ih acquired in step 106 (third acquisition unit). To calculate a possible range of the power converter input current value Ib acquired in step 104 (second acquisition unit).

  Specifically, in step 140, the control device 17 executes the same process as in step 108 described above. In step 142, the control device 17 calculates the upper limit threshold value of the power converter input current value Ib in the same manner as in step 110 described above. In step 144, the controller 17 calculates the power converter input current value Ib in the same manner as in step 112 described above. A lower limit threshold is calculated. The range from the upper limit threshold value to the lower limit threshold value of the power conversion unit input current value Ib calculated in this way is a possible range of the acquired power conversion unit input current value Ib.

  In step 146, similarly to step 114 described above, the control device 17 determines that the acquired power conversion unit input current value Ib is greater than or obtained from the calculated upper limit threshold value of the power conversion unit input current value Ib. It is determined whether the power conversion unit input current value Ib is smaller than the calculated lower limit threshold value of the power conversion unit input current value Ib.

  When the acquired power conversion unit input current value Ib is within the calculated possible range, the control device 17 determines “NO” in step 146, and the first current sensor 16j and the second current sensor 16k. Is detected to be normal (determined to be normal).

When the acquired power conversion unit input current value Ib is outside the calculated range, the control device 17 determines “YES” in step 146, and the first current sensor 16j and / or the second current is determined. It is detected that the sensor 16k is in an abnormal state that is abnormal (determined as being in an abnormal state).
The above-described steps 140 to 146 and 118 and 124 are the first determination unit.

  According to the first embodiment and the second embodiment described above, the first determination unit acquires the fuel cell output current value Ia acquired at step 102 (first acquisition unit) and step 104 (second acquisition unit). The other possible range is calculated from one of the power conversion unit input current value Ib and the auxiliary machine consumption current value Ih acquired in step 106 (third acquisition unit), and the other of the acquired values is calculated. If it is outside the possible range, it is determined that the first current sensor 16j and / or the second current sensor 16k is in an abnormal state, and the other of the acquired values is calculated. If it is within the range to be obtained, it is determined that the first current sensor 16j and the second current sensor 16k are normal.

  Accordingly, at least one of the first current sensor 16j and the second current sensor 16k is provided without detecting another current sensor for detecting an abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not the abnormal state is abnormal. In addition, it is possible to reliably and accurately determine whether or not the first current sensor 16j and the second current sensor 16k are normal.

  Third, the case where the result of subtracting the fuel cell output current value Ia and the power converter input current value Ib and the auxiliary machine consumption current value Ih are compared (third embodiment) will be described with reference to FIG. To do. In the first embodiment described above, it is determined whether or not the obtained fuel cell output current value Ia is within the calculated possible range, whereas in the second embodiment, the obtained value is obtained. The difference is that it is determined whether or not the current difference between the fuel cell output current value Ia and the acquired power converter input current value Ib is within the calculated range. The same processes as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

Specifically, the processing in steps 140 to 164 is performed instead of the processing in steps 108 to 114 in the first embodiment.
In step 160, the control device 17 responds to the fuel cell output current value Ia acquired by step 102 (first acquisition unit) or the power conversion unit input current value Ib acquired by step 104 (second acquisition unit). The upper and lower limit threshold values (possible ranges) of the auxiliary machine consumption current value Ih (that is, the current value difference between the fuel cell output current value Ia and the power converter input current value Ib) are calculated from the map shown in FIG.

  The control device 17 calculates a current value difference between the acquired fuel cell output current value Ia and the acquired power conversion unit input current value Ib (step 162), and uses the calculation result to determine the above-described step 114. Instead, the process of step 164 is executed. In step 164, control device 17 determines whether or not the calculated current value difference is outside the predetermined range, that is, outside the range between the upper and lower limit threshold values of auxiliary machine consumption current value Ih.

When the calculated current value difference is within the predetermined range, the control device 17 determines “NO” in step 164 and detects that the first current sensor 16j and the second current sensor 16k are normal ( Determined to be normal). If the calculated current value difference is outside the predetermined range, the control device 17 determines “YES” in step 164, and is in an abnormal state in which the first current sensor 16j and / or the second current sensor 16k is abnormal. It detects that there is (determines that it is in an abnormal state).
The above-described steps 160 to 164 and 118 and 124 are the first determination unit.

  Accordingly, at least one of the first current sensor 16j and the second current sensor 16k is provided without detecting another current sensor for detecting an abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not the abnormal state is abnormal. In addition, it is possible to reliably and accurately determine whether or not the first current sensor 16j and the second current sensor 16k are normal.

  According to the first determination unit in the first to third embodiments described above, the fuel cell output current value Ia acquired in step 102 (first acquisition unit) is acquired in step 104 (second acquisition unit). The power conversion unit input current value Ib and the auxiliary machine consumption current value Ih acquired at step 106 (third acquisition unit) are selected, and the addition result or subtraction result of the two values and the rest And at least one of the first current sensor 16j and the second current sensor 16k is determined based on a result of the comparison.

(Second and third current sensors)
Next, the second current sensor 16k and the third current sensor 16l will be described with reference to two examples.
First, the power conversion unit input current value Ib (and / or the power conversion unit output current value Ic) and the current value corresponding to the conversion loss in the power conversion unit and within a predetermined range Ig (hereinafter, FIG. 6 shows a case in which the result of addition or subtraction of the loss current value) is compared with the power conversion unit output current value Ic (and / or the power conversion unit input current value Ib) (fourth embodiment). The description will be given with reference.

  When a start switch (not shown) is turned on (or when the start is automatically started when a start start time set in advance by the user is reached), the control device 17 corresponds to the flowchart shown in FIG. Start running. This program is executed every predetermined short time.

  In step 202, the control device 17 acquires the power conversion unit input current value Ib detected by the second current sensor 16k (second acquisition unit), as in step 104. In step 204, the control device 17 acquires the power converter output current value Ic detected by the third current sensor 16l (fourth acquisition unit).

  In step 206, the control device 17 acquires the loss current value Ig stored in advance in the storage unit 18 (fifth acquisition unit). The acquired loss current value Ig may be indicated by a map (or table) or may be a predetermined constant value. The loss current value Ig represents a current difference between the power conversion unit input current value Ib and the power conversion unit output current value Ic. As shown in FIG. 7, the loss current value Ig is correlated with the power conversion unit output current value Ic (or the power conversion unit input current value Ib), and the power conversion unit output current value Ic (or the power conversion unit input current). The larger the value Ib), the larger the loss current value Ig.

  The map in FIG. 7 can be calculated from the map shown in FIG. The map shown in FIG. 8 shows the correlation between the power converter output current value Ic and the power converter input current value Ib. The power converter input current value Ib increases as the power converter output current value Ic increases. The difference between the upper and lower limit values of the power converter input current value Ib is constant regardless of the magnitude of the power converter output current value Ic. In the map of FIG. 8, the parameters of the horizontal axis and the vertical axis may be interchanged, and at this time, a map in which the horizontal axis of the map of FIG. 7 is replaced with the power converter input current can be created.

  In step 208, the control device 17 determines whether or not one cycle has elapsed since the start of this program. In the case of 50 Hz, it is determined whether 1/50 seconds have elapsed, or in the case of 60 Hz, it is determined whether 1/60 seconds have elapsed. If one cycle has not elapsed, the control device 17 determines “NO” in step 208, and once ends the program. If one cycle has elapsed, the control device 17 determines “YES” in step 208 and advances the program to step 210.

  In steps 210 to 216, the control device 17 includes the power conversion unit input current value Ib acquired in step 202 (second acquisition unit), the loss current value Ig acquired in step 206 (fifth acquisition unit), and To the power converter output current value Ic (effective value) acquired by step 204 (fourth acquisition unit) and the power converter output current acquired by step 204 (fourth acquisition unit) Possible range of the power converter input current value Ib acquired by Step 202 (second acquisition unit) from the value Ic (effective value) and the loss current value Ig acquired by Step 206 (Fifth acquisition unit) Is calculated.

  Specifically, in step 210, the control device 17 calculates the effective value (= maximum current value in one cycle / √2) from the power conversion unit output current value Ic acquired in step 204 (fourth acquisition unit). Calculate (effective value calculation unit). In step 212, the control device 17 calculates an average value (first average value) during one cycle of the power conversion unit input current value Ib acquired in step 202 (second acquisition unit) (first average value). Value calculator).

  In step 214, the control device 17 determines the acquired loss current value Ig (the power conversion unit input current value Ib and the power conversion unit output current value Ic) from the effective value of the power conversion unit output current value Ic and the map shown in FIG. The upper limit value and the lower limit value of the current difference from the effective value of (2) are calculated. For example, when the effective value of the power conversion unit output current value Ic is Ic1, the upper limit value of the loss current value Ig is Ig1max, the lower limit value of the loss current value Ig is Ig1min, and the power conversion unit output current value Ic When the effective value is Ic2, the upper limit value of the loss current value Ig is Ig2max, and the lower limit value of the loss current value Ig is Ig2min.

  In step 214, the control device 17 further calculates the upper limit value of the power converter input current Ib by adding the calculated effective value of the power converter output current value Ic and the upper limit value of the calculated loss current value Ig. At the same time, the calculated effective value of the power conversion unit output current value Ic and the calculated lower limit value of the loss current value Ig are added to calculate the lower limit value of the power conversion unit input current Ib. The range from the upper limit value to the lower limit value of the power conversion unit input current Ib calculated in this way is a possible range of the acquired power conversion unit input current Ib.

  Further, in step 216, similarly to step 214, the controller 17 calculates the power conversion unit input current value Ib (average value) and the power conversion unit input current value Ib and the loss power value similar to the map shown in FIG. The upper limit value and lower limit value of the acquired loss current value Ig are calculated from the map indicating the correlation. Then, the upper and lower limit values of the effective value of the power converter output current value Ic are calculated from the calculated power converter input current value Ib (average value) and the loss current value Ig.

  In steps 218 to 228, the control device 17 determines that the calculated average value of the power converter input current value Ib is out of the calculated range, that is, the upper limit value from the upper limit value of the average value of the power converter input current value Ib. When the value is out of the range up to the value, and / or the calculated effective value of the power conversion unit output current value Ic is out of the calculated range, that is, the upper limit value from the upper limit value of the effective value of the power conversion unit output current value Ic When it is out of the range up to the value, it is determined that the second current sensor 16k and / or the third current sensor 161 is in an abnormal state. On the other hand, the average value of the calculated power conversion unit input current value Ib is within the calculated possible range, and the calculated effective value of the power conversion unit output current value Ic is within the calculated possible range. In some cases, it is determined that the second current sensor 16k and the third current sensor 16l are normal.

  Specifically, the average value of the calculated power conversion unit input current value Ib is within the range from the upper limit value to the lower limit value of the calculated power conversion unit input current value Ib, and the calculated power conversion unit When the effective value of the output current value Ic is within the range from the upper limit value to the lower limit value of the calculated power converter output current value Ic, the control device 17 determines “YES” in step 218 and executes the program. Proceed to step 220. In step 220, the control device 17 clears the count of the elapsed time timer, and in step 222, detects that the second current sensor 16k and the third current sensor 161 are normal (determines that they are normal).

  The average value of the calculated power conversion unit input current value Ib is outside the range from the upper limit value to the lower limit value of the calculated power conversion unit input current value Ib, and / or the calculated power conversion unit output current value When the effective value of Ic is outside the range from the upper limit value to the lower limit value of the calculated power converter output current value Ic, the control device 17 determines “NO” in step 218 and sets the program to step 224. Proceed. In step 224, the control device 17 determines the elapsed time during which the state in which at least one of the average value of the power conversion unit input current value Ib and the effective value of the power conversion unit output current value Ic is outside the calculated range is continued. Counts up the elapsed time timer that represents it.

  Until the elapsed time timer exceeds a threshold value (for example, 5 seconds), that is, at least one of the average value of the power converter input current value Ib and the effective value of the power converter output current value Ic is out of the possible range. If the abnormal state does not continue for the threshold time or longer, the control device 17 determines “NO” in step 226 and temporarily ends the program.

When the elapsed time timer is equal to or greater than a threshold (for example, 5 seconds), that is, an abnormality in which at least one of the average value of the power conversion unit input current value Ib and the effective value of the power conversion unit output current value Ic is out of the calculated range If the state continues for the threshold time or longer, the control device 17 determines “YES” in step 226 and advances the program to step 228. In step 228, the control device 17 detects that the second current sensor 16k and / or the third current sensor 16l is in an abnormal state (determines that it is in an abnormal state). In step 228, it cannot be specified which of the second current sensor 16k and the third current sensor 161 is out of order.
The processes in steps 214 to 218 and 222 and 228 described above are the second determination unit.

  Here, the reason why the abnormality can be determined will be described. Input power to the power conversion unit (consisting of DC / DC converter 16a and DC / AC inverter 16b) is consumed and output by the conversion loss in the power conversion unit. In other words, the current difference between the power conversion unit input current value Ib detected by the second current sensor 16k and the power conversion unit output current value Ic detected by the third current sensor 161 is lost by the conversion in the power conversion unit. That is, it is substantially equal to the loss current value.

  Therefore, when both the second current sensor 16k and the third current sensor 16l are normal, the power conversion unit input current value Ib detected by the second current sensor 16k and the power conversion unit detected by the third current sensor 16l. The current difference from the output current value Ic is within a predetermined range. On the other hand, when at least one of the second current sensor 16k and the third current sensor 16l is abnormal, the power conversion unit input current value Ib detected by the second current sensor 16k and the power conversion detected by the third current sensor 16l. The current difference from the partial output current value Ic is outside the predetermined range.

  Accordingly, at least one of the second current sensor 16k and the third current sensor 16l is provided without providing another current sensor for detecting an abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not the abnormal state is abnormal.

  Second, a case where the result of subtracting the effective value of the power converter output current value Ic and the average value of the power converter input current value Ib is compared with the loss current value Ig (fifth embodiment) is shown in FIG. Will be described with reference to FIG. In the fourth embodiment described above, it is determined whether or not the average value of the power converter input current value Ib and the effective value of the power converter output current value Ic are within the calculated possible ranges. On the other hand, in the fifth embodiment, it is determined whether or not the current difference between the effective value of the power converter output current value Ic and the average value of the power converter input current value Ib is within the calculated possible range. Is different. The same processes as those in the fourth embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

Specifically, the processing of steps 240 to 244 is performed instead of the processing of steps 214 to 218 of the fourth embodiment.
In step 240, the control device 17 determines that the power converter input current value Ib calculated in step 212 or the loss current value Ig corresponding to the power converter output current value Ic calculated in step 210 (that is, the power converter input current). Upper and lower limit threshold values (possible ranges) of the current value difference between the value Ib and the power converter output current value Ic are calculated from the map shown in FIG.

  The control device 17 calculates a current value difference between the calculated power conversion unit input current value Ib and the calculated power conversion unit output current value Ic (step 242), and uses the calculation result to perform the above-described step. Instead of 218, the processing of step 244 is executed. In step 244, the control device 17 determines whether or not the calculated current value difference is outside the predetermined range, that is, within the range of the upper and lower limit values of the loss current value Ig.

If the calculated current value difference is within the predetermined range, the control device 17 determines “YES” in step 244 and detects that the second current sensor 16k and the third current sensor 16l are normal ( Determined to be normal). When the calculated current value difference is out of the predetermined range, the control device 17 determines “NO” in step 244 and is in an abnormal state in which the second current sensor 16k and / or the third current sensor 161 is abnormal. It detects that there is (determines that it is in an abnormal state).
The processes in steps 240 to 244 and 222 and 228 described above are the second determination unit.

  This makes it possible to reliably and accurately determine whether the second current sensor 16k and the third current sensor 16l are normal.

  According to the second determination unit of the fourth and fifth embodiments described above, the first average value of the power converter input current value Ib calculated by step 212 (first average value calculation unit), step 210 Any two of the effective value of the power conversion unit output current value Ic calculated by the (effective value calculation unit) and the loss current value Ig acquired by step 206 (fifth acquisition unit) are selected, and 2 The result of adding or subtracting two values is compared with the remaining one, and based on the comparison result, it is determined whether or not at least one of the second current sensor 16k and the third current sensor 16l is in an abnormal state. judge.

(Third and first current sensor)
Next, the third current sensor 161 and the first current sensor 16j will be described with reference to two examples.
First, a current obtained by adding the fuel cell output current value Ia (and / or the power converter output current value Ic), the current value consumed by the auxiliary machine 15, and the current value corresponding to the conversion loss in the power converter. The value If within a predetermined range If (hereinafter referred to as consumption / loss current value. = Auxiliary consumption current value Ih + loss current value Ig) is added or subtracted, and power converter output current value A case of comparing Ic (and / or fuel cell output current value Ia) (sixth embodiment) will be described with reference to FIG. The sixth embodiment is basically the same as the fourth embodiment, and different points will be described below. About the same point, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

In step 302, the control device 17 acquires the fuel cell output current value Ia detected by the first current sensor 16j in the same manner as in step 104 (first acquisition unit).
In step 304, the control device 17 acquires the consumption / loss current value If stored in advance in the storage unit 18 (sixth acquisition unit). The acquired consumption / loss current value If may be shown in a map (or table) or may be a predetermined constant value. The consumption / loss current value If represents the current difference between the fuel cell output current value Ia and the power converter output current value Ic. The consumption / loss current value If is correlated with the power converter output current value Ic (or the fuel cell output current value Ia), as shown by a map similar to the map of FIG. 7, and the power converter output current value Ic. As the fuel cell output current value Ia increases, the consumption / loss current value If increases.

  In steps 210 and 306 to 310, the control device 17 determines the fuel cell output current value Ia acquired in step 302 (first acquisition unit) and the consumption / loss current value acquired in step 304 (sixth acquisition unit). And the power conversion unit acquired by step 204 (fourth acquisition unit) and the possible range of the power conversion unit output current value Ic (effective value) acquired by step 204 (fourth acquisition unit). The fuel cell output current value Ia acquired by step 302 (first acquisition unit) from the partial output current value Ic (effective value) and the consumption / loss current value If acquired by step 304 (sixth acquisition unit). The range that can be taken is calculated.

  Specifically, in step 210, the control device 17 calculates the effective value (= maximum current value in one cycle / √2) from the power conversion unit output current value Ic acquired in step 204 (fourth acquisition unit). Calculate (effective value calculation unit). In step 306, the control device 17 calculates an average value (second average value) during one cycle of the fuel cell output current value Ia acquired by step 302 (first acquisition unit) (second average value). Calculation part).

  In step 308, the control device 17 determines the acquired consumption / loss current value If (the fuel cell output current value Ia and the current value Ia from the effective value of the power converter output current value Ic and the map similar to FIG. The upper and lower limit values of the current difference from the effective value of the power converter output current value Ic are calculated. Further, the control device 17 calculates an upper limit value and a lower limit value of the fuel cell output current value Ia. Further, in step 310, similarly to step 308, the control device 17 calculates the upper limit value and the lower limit value of the acquired consumption / loss current value If, and sets the upper and lower limit values of the effective value of the power converter output current value Ic. calculate.

  Then, in Steps 312, 220, 314, 224, 226, and 316, the control device 17 determines that the average value of the calculated fuel cell output current value Ia is out of the calculated range, that is, the average of the fuel cell output current value Ia. When the value is outside the range from the upper limit value to the lower limit value, and / or the calculated effective value of the power converter output current value Ic is outside the possible range of calculation, that is, the effective value of the power converter output current value Ic When the value is outside the range from the upper limit value to the lower limit value, it is determined that the first current sensor 16j and / or the third current sensor 161 is in an abnormal state. On the other hand, the average value of the calculated fuel cell output current value Ia is within the calculated possible range, and the calculated effective value of the power converter output current value Ic is within the calculated possible range. In this case, it is determined that the first current sensor 16j and the third current sensor 16l are normal.

  Specifically, the average value of the calculated fuel cell output current value Ia is within the range from the upper limit value to the lower limit value of the calculated fuel cell output current value Ia, and the calculated power converter output current When the effective value of the value Ic is within the range from the upper limit value to the lower limit value of the calculated power converter output current value Ic, the control device 17 determines “YES” in step 312 and the program is executed in step 220. Go ahead. In step 314, the control device 17 detects that the first current sensor 16j and the third current sensor 16l are normal (determines that they are normal).

The average value of the calculated fuel cell output current value Ia is out of the range from the upper limit value to the lower limit value of the calculated fuel cell output current value Ia, and / or the calculated power converter output current value Ic When the effective value is out of the range from the upper limit value to the lower limit value of the calculated power conversion unit output current value Ic, the control device 17 determines “NO” in step 312 and advances the program to step 224 and the subsequent steps. . In step 316, the control device 17 detects that the first current sensor 16j and / or the third current sensor 16l is in an abnormal state (determines that it is in an abnormal state). In step 316, it cannot be specified which of the first current sensor 16j and the third current sensor 16l has failed.
Steps 308 to 312 and steps 314 and 316 described above are the third determination unit.

  Accordingly, at least one of the first current sensor 16j and the third current sensor 16l is not provided without providing another current sensor for detecting an abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not the abnormal state is abnormal.

  Secondly, the result of subtracting the average value of the fuel cell output current value Ia and the effective value of the power converter output power value Ic is compared with the consumption / loss current value If (seventh embodiment). 11 will be described. In the sixth embodiment described above, it is determined whether the average value of the fuel cell output current value Ia and the effective value of the power converter output current value Ic are within the calculated possible ranges, respectively. Thus, in the seventh embodiment, it is determined whether or not the current difference between the average value of the fuel cell output current value Ia and the effective value of the power converter output current value Ic is within the calculated possible range. Is different. The same processes as those in the sixth embodiment described above are denoted by the same reference numerals, and the description thereof is omitted.

Specifically, the processing of steps 340 to 344 is performed instead of the processing of steps 308 to 312 of the sixth embodiment.
In step 340, the control device 17 determines the consumption / loss current value If according to the average value of the fuel cell output current value Ia calculated in step 306 or the effective value of the power converter output current value Ic calculated in step 210. That is, upper and lower limit values (possible ranges) of the current value difference between the average value of the fuel cell output current value Ia and the effective value of the power converter output current value Ic are calculated from a map similar to the map shown in FIG. .

  The control device 17 calculates a current value difference between the calculated average value of the fuel cell output current value Ia and the calculated effective value of the power converter output current value Ic (step 342), and uses the calculation result. Thus, the process of step 344 is executed instead of step 312 described above. In step 344, the controller 17 determines whether or not the calculated current value difference is outside the predetermined range, that is, within the range from the upper limit value to the lower limit value of the consumption / loss current value If.

If the calculated current value difference is within the predetermined range, the control device 17 determines “YES” in step 344 and detects that the first current sensor 16j and the third current sensor 16l are normal ( Determined to be normal). When the calculated current value difference is outside the predetermined range, the control device 17 determines “NO” in step 344, and is in an abnormal state in which the first current sensor 16j and / or the third current sensor 16l is abnormal. It detects that there is (determines that it is in an abnormal state).
The processes from steps 340 to 344 and 314 and 316 described above are the third determination unit.
Thereby, it is possible to reliably and accurately determine whether or not the first current sensor 16j and the third current sensor 16l are normal.

  According to the third determination unit of the sixth embodiment and the seventh embodiment described above, the second average value of the fuel cell output current value Ia calculated by step 306 (second average value calculation unit), step 210 ( The effective value of the power conversion unit output current value Ic calculated by the effective value calculation unit) and the consumption / loss current value If acquired by step 304 (sixth acquisition unit) are selected, and these are selected. Whether the result of adding or subtracting two values is compared with the remaining one, and whether or not at least one of the first current sensor 16j and the third current sensor 16l is abnormal based on the comparison result Determine.

Furthermore, the identification that the first to third current sensors 16j to 16l are abnormal based on the determination results of the first to third determination units described above will be described with reference to FIGS.
In steps 402, 404, and 406, the control device 17 acquires the determination results of the first to third determination units described above. The control device 17 performs identification that the first to third current sensors 16j to 16l are abnormal based on the table shown in FIG. 13 and the determination results of the first to third determination units.

  As shown in FIG. 13, when the first to third current sensors 16j to 16l are all in the first pattern that is abnormal, the determination results of the first to third determination units are all abnormal. Even when the first and second current sensors 16j and 16k are abnormal and the third current sensor 161 is a normal second pattern, the determination results of the first to third determination units are all abnormal. Even when the first and third current sensors 16j and 16l are abnormal and the second current sensor 16k is the third pattern, the determination results of the first to third determination units are all abnormal. Even when the second and third current sensors 16k, 16l are abnormal and the first current sensor 16j is in the fifth pattern, the determination results of the first to third determination units are all abnormal.

  Further, when the second and third current sensors 16k and 16l are in the fourth pattern in which the first current sensor 16j is abnormal and the first current sensor 16j is abnormal, the determination results of the first and third determination units are abnormal and The determination result of the second determination unit is normal. When the first and third current sensors 16j and 16l are normal and the second current sensor 16k is the sixth pattern, the determination result of the first and second determination units is abnormal and the third The determination result of the determination unit is normal. When the first and second current sensors 16j and 16k are normal and the third current sensor 16l is in the seventh pattern, the determination result of the second and third determination units is abnormal and the first The determination result of the determination unit is normal. When the first to third current sensors 16j to 16l are in the eighth pattern that is all normal, the determination results of the first to third determination units are all normal.

  Therefore, in step 408, the control device 17 specifies that the first current sensor 16j is abnormal when the pattern is the fourth pattern. Note that the control device 17 also outputs the first determination result when the determination result of the second determination unit is normal and the determination result of the first determination unit is abnormal or the determination result of the third determination unit is abnormal. 1 Current sensor 16j is identified as abnormal.

  Moreover, the control apparatus 17 specifies that the 1st electric current sensor 16j is abnormal in step 408, when it is a 4th pattern. Further, the control device 17 specifies that the first current sensor 16j is abnormal even when the determination result of the second determination unit is normal and the determination result of the first determination unit is abnormal (first 1 specific part). Furthermore, the control device 17 specifies that the first current sensor 16j is abnormal even when the determination result of the second determination unit is normal and the determination result of the third determination unit is abnormal.

  Further, in step 410, the control device 17 specifies that the second current sensor 16k is abnormal when it is the sixth pattern. Further, the control device 17 specifies that the second current sensor 16k is abnormal even when the determination result of the third determination unit is normal and the determination result of the first determination unit is abnormal (first 2 specific part). Furthermore, the control device 17 specifies that the second current sensor 16k is abnormal even when the determination result of the third determination unit is normal and the determination result of the second determination unit is abnormal.

Furthermore, in step 412, the control device 17 specifies that the third current sensor 161 is abnormal when the pattern is the seventh pattern (third specifying unit). Further, the control device 17 specifies that the third current sensor 161 is abnormal even when the determination result of the first determination unit is normal and the determination result of the second determination unit is abnormal (first 3 specific part). Further, the control device 17 specifies that the third current sensor 161 is abnormal even when the determination result of the first determination unit is normal and the determination result of the third determination unit is abnormal (third). Specific part).
Further, in step 414, the control device 17 determines that all of the first to third current sensors 16j to 16l are normal when the pattern is the eighth pattern.

  According to the above-described embodiment, the first determination unit determines that at least one of the first current sensor 16j and the second current sensor 16k is in an abnormal state, and the second determination unit detects the second current sensor. When it determines with 16k and the 3rd current sensor 161 being normal, the 1st specific | specification part which specifies that the 1st current sensor 16k is abnormal is further provided. Thereby, it is possible to accurately and reliably determine whether or not the first current sensor 16j is normal.

  The first determination unit determines that at least one of the first current sensor 16j and the second current sensor 16k is abnormal, and the third determination unit determines that the first current sensor 16j and the third current sensor are abnormal. When it is determined that 16l is normal, a second specifying unit that specifies that the second current sensor 16k is abnormal is further provided. Thereby, it can be determined accurately and reliably whether or not the second current sensor 16k is normal.

  The fourth acquisition unit (step 204) acquires the power conversion unit output current value detected by the third current sensor 16l that detects the output current value from the power conversion unit. The fifth acquisition unit (step 206) acquires a current value corresponding to the conversion loss in the power conversion unit stored in advance in the storage unit 18 and within a predetermined range. The sixth acquisition unit (step 304) is a current value that is stored in advance in the storage unit 18 and that is obtained by adding the current value consumed by the auxiliary machine and the current value corresponding to the conversion loss in the power conversion unit. Get something that is in the range of. The first average value calculation unit (step 212) calculates a first average value from the power conversion unit input current value acquired by the second acquisition unit. The second average value calculation unit (step 306) calculates a second average value from the fuel cell output current value acquired by the first acquisition unit (step 102). The effective value calculation unit (step 210) calculates an effective value from the power conversion unit output current value acquired by the fourth acquisition unit. The second determination unit includes a first average value of the power conversion unit input current value calculated by the first average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and a fifth Select any two of the loss current values acquired by the acquisition unit, compare the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the second current sensor 16k and It is determined whether or not at least one of the third current sensors 161 is in an abnormal state. The third determination unit includes a second average value of the fuel cell output current value calculated by the second average value calculation unit, an effective value of the power conversion unit output current value calculated by the effective value calculation unit, and a first 6 Select any two of the current values acquired by the acquisition unit, compare the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the first current sensor 16j and It is determined whether or not at least one of the third current sensors 161 is in an abnormal state. Accordingly, at least one of the first current sensor 16j to the third current sensor 16l is provided without detecting another current sensor for detecting an abnormality of the current sensor, that is, without increasing the cost and increasing the size of the system. It can be determined whether or not the abnormal state is abnormal.

  The first determination unit determines that the first current sensor 16j and the second current sensor 16k are normal, and the second determination unit determines that at least one of the second current sensor 16k and the third current sensor 16l is abnormal. When it is determined that there is an abnormal state, and / or when the third determination unit determines that at least one of the first current sensor 16j and the third current sensor 161 is abnormal, the third current sensor A third specifying unit that specifies that 16l is abnormal is further provided. Thereby, it can be determined accurately and reliably whether the third current sensor 16l is normal.

In the above-described embodiment, the DC / DC converter 16a is provided on the third power supply line L3. However, the DC / DC converter 16a is provided on the first power supply line L1 and the third power supply line L3. A DC / DC converter 16a may be provided between the junction and the fuel cell 11d. In this case, the power conversion unit is configured only by the DC / AC inverter 16b.
In the above-described embodiment, the fuel cell is a solid oxide fuel cell. However, the present invention may be applied to a fuel cell system of a polymer electrolyte fuel cell.

  DESCRIPTION OF SYMBOLS 11 ... Fuel cell module, 11a ... Casing, 11b ... Evaporating part, 11c ... Reforming part, 11d ... Fuel cell, 12 ... System power supply, 13 ... Power supply line, 14 ... Electric power load, 15 ... Auxiliary machine, 16 ... Inverter device 16a ... DC / DC converter, 16b ... DC / AC inverter, 16c ... AC / DC converter, 16d ... DC / DC converter for control, 16e ... DC / DC converter for auxiliary machinery, 16h ... first switch, 16j ... first 1 current sensor, 16k ... 2nd current sensor, 16l ... 3rd current sensor, 17 ... control device (1st-6th acquisition part, 1st-3rd determination part, 1st and 2nd average value calculation part, effective Value calculation unit, first to third identification unit).

Claims (9)

A first acquisition unit that acquires the fuel cell output current value detected by a first current sensor that detects an output current value from the fuel cell;
Detected by a second current sensor that detects an input current value to a power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to an external load A second acquisition unit for acquiring the power conversion unit input current value;
A third acquisition unit that acquires a current value that is consumed in the auxiliary device and stored in advance in a storage unit and that is within a predetermined range;
One of the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the consumption current value acquired by the third acquisition unit Two are selected, the result of adding or subtracting the two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result A first determination unit for determining whether or not an abnormal state;
A fourth acquisition unit that acquires the power conversion unit output current value detected by a third current sensor that detects an output current value from the power conversion unit;
A fifth acquisition unit that acquires a current value corresponding to the conversion loss in the power conversion unit stored in advance in the storage unit and that is within a predetermined range;
A first average value calculation unit that calculates a first average value from the power conversion unit input current value acquired by the second acquisition unit;
An effective value calculation unit that calculates an effective value from the output current value of the power conversion unit acquired by the fourth acquisition unit;
The first average value of the power conversion unit input current value calculated by the first average value calculation unit, the effective value of the power conversion unit output current value calculated by the effective value calculation unit, and the fifth acquisition Selecting any two of the loss current values acquired by the unit, comparing the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the second current sensor and the A fuel cell system control device comprising: a second determination unit that determines whether or not at least one of the third current sensors is in an abnormal state. 2. The first determination unit according to claim 1 , wherein the first determination unit determines that at least one of the first current sensor and the second current sensor is in an abnormal state, and the second determination unit includes the second current sensor. And a control device for a fuel cell system, further comprising: a first specifying unit that specifies that the first current sensor is abnormal when it is determined that the third current sensor is normal. A first acquisition unit that acquires the fuel cell output current value detected by a first current sensor that detects an output current value from the fuel cell;
Detected by a second current sensor that detects an input current value to a power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to an external load A second acquisition unit for acquiring the power conversion unit input current value;
A third acquisition unit that acquires a current value that is consumed in the auxiliary device and stored in advance in a storage unit and that is within a predetermined range;
One of the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the consumption current value acquired by the third acquisition unit Two are selected, the result of adding or subtracting the two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result A first determination unit for determining whether or not an abnormal state;
A fourth acquisition unit that acquires the power conversion unit output current value detected by a third current sensor that detects an output current value from the power conversion unit;
A current value that is stored in advance in the storage unit and that is obtained by adding the current value consumed by the auxiliary device and the current value corresponding to the conversion loss in the power conversion unit, and that is within a predetermined range is acquired. A sixth acquisition unit;
A second average value calculation unit for calculating a second average value from the fuel cell output current value acquired by the first acquisition unit;
An effective value calculation unit that calculates an effective value from the output current value of the power conversion unit acquired by the fourth acquisition unit;
A second average value of the fuel cell output current value calculated by the second average value calculation unit; an effective value of the power conversion unit output current value calculated by the effective value calculation unit; and the sixth acquisition unit. And selecting one of the current values obtained by the above, comparing an addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the first current sensor and the third current value A fuel cell system control device comprising: a third determination unit that determines whether or not at least one of the current sensors is in an abnormal state. 4. The method according to claim 3 , wherein the first determination unit determines that an abnormal state in which at least one of the first current sensor and the second current sensor is abnormal and the third determination unit is the first current sensor. And a control device for a fuel cell system, further comprising: a second specifying unit that specifies that the second current sensor is abnormal when it is determined that the third current sensor is normal. A first acquisition unit that acquires the fuel cell output current value detected by a first current sensor that detects an output current value from the fuel cell;
Detected by a second current sensor that detects an input current value to a power conversion unit that inputs and converts at least the remaining power after being supplied to the auxiliary machine out of the output power of the fuel cell and outputs it to an external load A second acquisition unit for acquiring the power conversion unit input current value;
A third acquisition unit that acquires a current value that is consumed in the auxiliary device and stored in advance in a storage unit and that is within a predetermined range;
One of the fuel cell output current value acquired by the first acquisition unit, the power conversion unit input current value acquired by the second acquisition unit, and the consumption current value acquired by the third acquisition unit Two are selected, the result of adding or subtracting the two values is compared with the remaining one, and at least one of the first current sensor and the second current sensor is abnormal based on the comparison result A first determination unit for determining whether or not an abnormal state;
A fourth acquisition unit that acquires the power conversion unit output current value detected by a third current sensor that detects an output current value from the power conversion unit;
A fifth acquisition unit that acquires a current value corresponding to the conversion loss in the power conversion unit stored in advance in the storage unit and that is within a predetermined range;
A current value that is stored in advance in the storage unit and that is obtained by adding the current value consumed by the auxiliary device and the current value corresponding to the conversion loss in the power conversion unit, and that is within a predetermined range is acquired. A sixth acquisition unit;
A first average value calculation unit that calculates a first average value from the power conversion unit input current value acquired by the second acquisition unit;
A second average value calculation unit for calculating a second average value from the fuel cell output current value acquired by the first acquisition unit;
An effective value calculation unit that calculates an effective value from the output current value of the power conversion unit acquired by the fourth acquisition unit;
The first average value of the power conversion unit input current value calculated by the first average value calculation unit, the effective value of the power conversion unit output current value calculated by the effective value calculation unit, and the fifth acquisition Selecting any two of the loss current values acquired by the unit, comparing the addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the second current sensor and the A second determination unit that determines whether or not at least one of the third current sensors is in an abnormal state;
A second average value of the fuel cell output current value calculated by the second average value calculation unit; an effective value of the power conversion unit output current value calculated by the effective value calculation unit; and the sixth acquisition unit. And selecting one of the current values obtained by the above, comparing an addition result or subtraction result of the two values with the remaining one, and based on the comparison result, the first current sensor and the third current value A third determination unit that determines whether or not at least one of the current sensors is in an abnormal state;
A control device for a fuel cell system. 6. The method of claim 5 , wherein the first determination unit determines that the first current sensor and the second current sensor are normal, and the second determination unit includes at least one of the second current sensor and the third current sensor. It is determined that one of the abnormal states is abnormal, and / or the third determination unit determines that at least one of the first current sensor and the third current sensor is abnormal. And a control device for a fuel cell system, further comprising a third specifying unit that specifies that the third current sensor is abnormal. 7. The fuel cell output current value acquired by the first acquisition unit and the power conversion unit acquired by the second acquisition unit according to claim 1. When the other possible range is calculated from one of the input current values and the consumption current value acquired by the third acquisition unit, and the other of the acquired values is outside the calculated possible range, When it is determined that the first current sensor or / and the second current sensor is in an abnormal state, and the other of the acquired values is within the calculated possible range, A control apparatus for a fuel cell system, wherein one current sensor and the second current sensor are determined to be normal. 7. The power conversion unit according to claim 1 , wherein the first determination unit includes the fuel cell output current value acquired by the first acquisition unit and the power conversion unit acquired by the second acquisition unit. Abnormality in which the first current sensor and / or the second current sensor is abnormal when the current value difference from the input current value is outside the predetermined range of the consumption current value acquired by the third acquisition unit On the other hand, if the current value difference is within the predetermined range, the control device for the fuel cell system determines that the first current sensor and the second current sensor are normal . A fuel cell system comprising the control device for a fuel cell system according to any one of claims 1 to 8 .

Images