JP4016536B2 - Output diagnosis device for fuel cell vehicles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an output diagnostic device for a fuel cell vehicle, and more particularly to an output diagnostic device for a fuel cell vehicle that can continue the operation of the vehicle until a warning is issued even when the fuel cell has deteriorated for a long time.
[0002]
[Prior art]
Conventionally, as a fuel cell vehicle, a hybrid fuel cell vehicle that travels by supplying electric power output from the fuel cell and the secondary battery to a drive motor is known. Such a fuel cell vehicle is equipped with an output diagnostic device for diagnosing the output states of the fuel cell and the secondary battery.
[0003]
This output diagnostic device monitors the lower limit voltage of each cell of the fuel cell and the secondary battery and the upper limit voltage and lower limit voltage of the representative cell group during operation, and when they exceed a certain limit value, Charging / discharging is stopped to protect the fuel cell and the secondary battery.
[0004]
Such a technique is reported, for example, in Japanese Patent Laid-Open No. 6-223859 regarding a fuel cell, and reported in Japanese Patent Laid-Open No. 8-168183 regarding a secondary battery.
[0005]
[Problems to be solved by the invention]
However, when the cell voltage of the secondary battery decreases, it always indicates cell deterioration, whereas when the cell voltage of the fuel cell decreases, it does not necessarily indicate cell deterioration. It may be due to a shortage. In this case, if the flow rate of the fuel supplied to the fuel cell is increased, the cell voltage is also increased, so that the operation stop of the fuel cell can be avoided.
[0006]
Thus, in a fuel cell, even if the cell voltage decreases temporarily, it does not immediately indicate cell deterioration and may be recoverable. On the other hand, in the secondary battery, a decrease in the cell voltage means deterioration of the cell itself, and once the cell voltage decreases, the cell voltage does not recover unless it is charged. Therefore, when diagnosing the output state of the fuel cell and the secondary battery, the same method cannot be applied to both.
[0007]
However, in the conventional fuel cell vehicle, it has not been possible to reliably determine whether the cause of the drop in the output voltage of the fuel cell is due to long-term deterioration of the cell. For this reason, since the vehicle load is constantly changing in actual driving, the fuel cell operation is stopped when the cell voltage of the fuel cell fluctuates and deviates from the predetermined range.
[0008]
As a result, the conventional fuel cell vehicle has a problem that it is forced to stop the operation which is originally unnecessary depending on the cell voltage of the fuel cell.
[0009]
The present invention has been made in view of the above. The purpose of the present invention is to provide a fuel that can continue running without stopping the operation of the vehicle until a warning is received even if the fuel cell has deteriorated for a long time. An object of the present invention is to provide an output diagnosis device for a battery car.
[0010]
[Means for Solving the Problems]
In order to solve the above problems, the invention according to claim 1 diagnoses the output state of the fuel cell for a fuel cell vehicle that travels by supplying electric power output from the fuel cell and the secondary battery to the drive motor. In a fuel cell vehicle output diagnostic device, when a vehicle is stopped, a predetermined operating condition is set with the temperature and pressure inside the fuel cell within specified ranges, and a predetermined current is output from the fuel cell to the secondary battery for a predetermined time. Fuel cell control means for controlling the output, output voltage detection means for detecting the output voltage output from the fuel cell, and control for outputting a predetermined current from the fuel cell for a predetermined time when the vehicle is stopped by the fuel cell control means. Output voltage storage means for storing the output voltage of the fuel cell at the time, and the current value which is the latest value stored in the output voltage storage means with respect to the output voltage of the fuel cell A calculating means for calculating an output drop rate than the stored initial value, the gist that a correcting means for correcting in accordance with the output decrease rate the maximum power that can be output from the fuel cell.
[0011]
In order to solve the above-mentioned problem, the invention described in claim 2 is an output voltage judgment means for judging whether or not the output voltage of the fuel cell detected by the output voltage detection means is a predetermined value or less, and is outputted from the fuel cell. The gist of the present invention is to provide a notifying means for notifying a warning for prompting the inspection or replacement of the fuel cell when the output voltage becomes a predetermined value or less.
[0012]
In order to solve the above problems, the invention according to claim 3 is characterized in that the output voltage detecting means detects the output voltage from individual cells or a plurality of cells constituting the fuel cell.
[0015]
【The invention's effect】
According to the first aspect of the present invention, when the vehicle is stopped, control is performed so that a predetermined current is output from the fuel cell to the secondary battery for a predetermined time, and the output voltage output from the fuel cell is detected and stored. To do. Then, the current value related to the output voltage of the fuel cell is compared with the initial value stored in advance to calculate the output reduction rate, and the maximum power that can be output from the fuel cell is corrected according to the output reduction rate. Since the output rate of the fuel cell is accurately calculated when the vehicle is low and the maximum power is corrected, even if the fuel cell has deteriorated for a long time, it can continue running without stopping the vehicle operation. can do.
[0016]
According to the second aspect of the present invention, when the output voltage of the fuel cell becomes a predetermined value or less, a warning prompting the inspection or replacement of the fuel cell is notified, so that the fuel cell is deteriorated for a long time. Even if it occurs, the vehicle can be operated with peace of mind until a warning is received, and when the warning is received, the service center can be immediately requested to check or replace the fuel cell.
[0017]
According to the third aspect of the present invention, since the output voltage is detected from each cell or a plurality of cells constituting the fuel cell, the fuel cell is individually or a plurality of cells. A warning prompting the inspection or replacement of the product can be notified.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0021]
(First embodiment)
FIG. 1 is a diagram showing the configuration of a system to which the output diagnostic apparatus for a fuel cell vehicle according to the first embodiment of the present invention can be applied.
[0022]
In the fuel reformer 11, a reformed gas containing hydrogen gas is generated from hydrocarbon, alcohol, or the like. On the other hand, the compressor 13 compresses air and supplies it to the fuel cell stack 15 and the fuel reformer 11.
[0023]
The fuel cell stack 15 is composed of a solid polymer membrane fuel cell, and generates electricity using hydrogen contained in the reformed gas from the fuel reformer 11 and oxygen contained in the air from the compressor 13. The power distributor 17 distributes the power generated by the fuel cell stack 15 to the vehicle load 19 and the secondary battery 21.
[0024]
The vehicle load 19 is a load generated when a motor driving the vehicle and other auxiliary machines are driven. The secondary battery 21 is made of lithium ion or metal hydride, is connected in parallel with the vehicle load, charges the power recovered from the motor by regeneration during braking, and assists the power supplied to the motor during rapid acceleration.
[0025]
A pressure adjusting valve 23 is provided in the middle of the piping of the reformed gas flowing into the fuel cell stack 15 from the fuel reformer 11 in order to adjust the pressure of the reformed gas air flowing into the fuel cell stack 15. . Further, a pressure adjusting valve 25 is provided in the middle of the piping of the air flowing into the fuel cell stack 15 from the fuel reformer 11 in order to adjust the pressure of the air flowing into the fuel cell stack 15.
[0026]
A pressure adjusting valve 31 is provided in the middle of the exhaust air piping discharged from the fuel cell stack 15 to the fuel reformer 11 in order to adjust the pressure of the reformed gas flowing into the fuel cell stack 15. A pressure adjusting valve 33 that adjusts the pressure of the air flowing into the fuel cell stack 15 is provided in the middle of the piping of the exhaust reformed gas discharged from the fuel cell stack 15 to the fuel reformer 11.
[0027]
The stack voltage sensor 35 and the stack current sensor 37 detect the voltage and current generated by the fuel cell stack 15 and output them to the fuel cell control device 51.
[0028]
The fuel cell stack 15 has a stack structure composed of a plurality of cells, and the stack voltage sensor 35 is configured to detect an output voltage individually or in units of a plurality of cells. Input to the battery control device 51.
[0029]
The pressure sensor 41 is provided in the middle of the piping of the reformed gas flowing into the fuel cell stack 15 from the fuel reformer 11, detects the pressure of the reformed gas, and outputs it to the fuel cell control device 51. The pressure sensor 43 is provided in the middle of the piping for the air flowing into the fuel cell stack 15 from the compressor 13, detects the pressure of the air, and outputs it to the fuel cell control device 51.
[0030]
The temperature sensors 45 and 47 are provided in the middle of the piping of exhaust reformed gas and exhaust air discharged from the fuel cell stack 15 to the fuel reformer 11, respectively, and detect the temperature of the exhaust reformed gas and exhaust air to detect the fuel cell. Output to the control device 51.
[0031]
The fuel cell control device 51 includes an internal RAM that stores control data, an internal ROM that stores a control program, and a CPU that controls the fuel cell system according to the control program.
[0032]
The drive control device 53 calculates the vehicle load power by summing the power required by each auxiliary machine constituting the vehicle load 19, and based on the power capacity remaining in the secondary battery 21 and the vehicle load power, the fuel cell stack 15 is calculated and transmitted to the fuel cell control device 51, and a distribution ratio for distributing the power generated by the fuel cell stack 15 to the vehicle load 19 and the secondary battery 21 is calculated to distribute power. Call the device 17.
[0033]
The discharge fixed resistor 55 is connected between output terminals provided in the fuel cell stack 15, and becomes a load of the fuel cell stack 15 by turning on the switch 57.
[0034]
Next, the output correction control process according to the power generation state of the stack by the fuel cell control device 51 will be described according to the flowchart shown in FIG.
[0035]
Here, the drive control device 53 outputs a stop command signal to the fuel cell control device 51 in accordance with an operation from the driver. The fuel cell control device 51 enters the stop sequence of the fuel cell stack 15 after receiving the stop command signal from the drive control device 53. In addition, since it takes about 1 to 2 minutes for the fuel reformer 11 to stop generating the reformed gas, the following stop process is performed using the reformed gas flowing into the fuel cell stack 15 during this time. To do.
[0036]
In this case, when the operation of the fuel cell stack 15 is stopped, power generation is performed in order to consume the hydrogen gas remaining in the stack, and from the power distributor 17 to the secondary battery 21 for a specified time with a specified current every time the stop is performed. To make a steady output.
[0037]
First, in step S10, in order to reduce the amount of reformed gas flowing into the fuel cell stack 15 from the fuel reformer 11, the opening of the pressure regulating valve 23 is adjusted according to a predetermined initial opening. To do.
[0038]
In step S20, in order to increase the inflow amount of exhaust reformed gas flowing from the fuel cell stack 15 into the fuel reformer 11, the opening degree of the pressure regulating valve 33 is set in accordance with a predetermined initial opening degree. adjust.
[0039]
In step S30, the temperature of the exhaust reformed gas is read from the temperature sensor 45 provided near the outlet of the fuel cell stack 15, and the pressure of the reformed gas is read from the pressure sensor 41 provided near the inlet of the fuel cell stack 15. To determine whether the temperature and pressure in the fuel cell stack 15 are within the specified ranges.
[0040]
Here, when the temperature and pressure in the fuel cell stack 15 are within the specified ranges, the process proceeds to step S50. On the other hand, when the temperature and pressure in the fuel cell stack 15 are not within the specified ranges, the process proceeds to step S40.
[0041]
If the temperature and pressure in the fuel cell stack 15 are not within the specified range, the difference between the actual temperature and pressure read from the temperature sensor 45 and the pressure sensor 41 with respect to the specified range is calculated in step S40. Find the sign. Then, this sign is inverted, and a new opening is obtained by increasing / decreasing the opening set in steps S10 and S20 by a predetermined minute opening according to the inversion sign, and the process returns to step S10. repeat.
[0042]
As a result, in the determination process in step S30, the difference amount in which the actual temperature and pressure are generated with respect to the specified range gradually approaches zero.
[0043]
In this way, the same operating condition can be set for each stop. Regarding the operating temperature and pressure, the voltage change width is grasped using a fuel cell stack that is mounted in advance, and the stop operation is performed at the operating temperature and pressure that do not deviate from the conditions within a certain voltage width.
[0044]
Since it is an operation that also serves as residual hydrogen treatment when the fuel cell stack is stopped, it is not preferable to supply an excess fuel flow rate and air flow rate. Therefore, use a low flow rate or use residual hydrogen and residual air in the stack. Do.
[0045]
On the other hand, when the temperature and pressure in the fuel cell stack 15 are within the specified ranges, in step S50, the switch 57 of the discharge fixed resistor 55 connected between the output terminals provided in the fuel cell stack 15 is turned on. Turn on control.
[0046]
In step S60, the electric power generated by the fuel cell stack 15 is output to the secondary battery 21 through the power distributor 17 in a steady manner. At the same time, a timer provided in the fuel cell control device 51 is started to measure time. In addition, when the cell voltage behavior of the fuel cell stack 15 at this time is measured, it is confirmed that all the cells exhibit substantially the same cell voltage in the initial stage where no deterioration has occurred.
[0047]
In general, for a fuel cell of the tens of kW class of a vehicle fuel cell, the discharge amount of several A is so small as to be negligible, so that the dependency on the hydrogen gas utilization rate during general operation need not be considered. . However, it is also possible to control the operation of the accessories so that the above-described temperature, pressure, and flow rate are within the specified range.
[0048]
Specifically, for example, for a few dozen seconds after stopping, a discharge with a current of about several A is performed at a temperature of about 85 ° C. under both atmospheric pressure and air pressure, and each cell voltage or group at that time is discharged. The cell voltage behavior is stored and compared with past records.
[0049]
In step S70, voltage data is read from the stack voltage sensor 35 provided in the fuel cell stack 15, and measurement time data and measurement date data are added to the voltage data and stored in the internal RAM of the fuel cell control device 51. Keep it. The stack voltage sensor 35 detects an output voltage from individual cells or a plurality of cells constituting the fuel cell stack 15.
[0050]
In step S80, time measurement data is read from a timer provided in the fuel cell control device 51 to determine whether the specified time has elapsed. The process returns to step S70 until the specified time has elapsed, and the process is repeated.
[0051]
As a result, the internal RAM of the fuel cell control device 51 stores output voltage data from the initial value to the current value for the fuel cell stack 15 for the same specified current.
[0052]
If the specified time has elapsed, in step S90, the initial value and the current value are read from the output voltage data of the fuel cell stack 15 stored in the internal RAM of the fuel cell control device 51, and the output reduction rate% is calculated. To do.
[0053]
[Expression 1]
Output reduction rate = {(initial value−current value) / initial value} × 100
In step S100, the maximum power that can be output from the fuel cell stack 15 is corrected according to the output reduction rate.
[0054]
That is, referring to FIG. 3, the current hydrogen utilization rate is calculated from the hydrogen utilization rate table corresponding to the output decrease rate stored in advance in the internal ROM of the fuel cell control device 51 and stored in the internal RAM. . As a result, the maximum power that can be output from the fuel cell stack 15 can be corrected by using this hydrogen utilization rate when the vehicle is started next time.
[0055]
At the start of the next vehicle operation, the hydrogen utilization rate stored in the internal RAM is read, and a hydrogen increase request is output to the fuel reformer 11 so as to achieve this hydrogen utilization rate. The fuel reformer 11 that has received the hydrogen increase request from the fuel cell control device 51 increases the amount of reformed gas produced in response to the hydrogen increase request.
[0056]
As a result, as an effect related to the first embodiment of the present invention, even when aging deterioration occurs in the output voltage of the fuel cell stack, the hydrogen utilization rate is corrected according to the output decrease rate. The maximum power that can be output from the fuel cell stack 15 can be taken out. In addition, since the output reduction rate of the fuel cell stack is accurately obtained and the maximum power is corrected when the vehicle stops with little load fluctuation, the vehicle operation is stopped even if long-term deterioration occurs in the fuel cell stack. Traveling can be continued without any problems.
[0057]
(Second Embodiment)
The configuration of the system to which the output diagnostic apparatus for a fuel cell vehicle according to the second embodiment of the present invention can be applied is the same as the basic configuration of the system corresponding to the first embodiment shown in FIG. The same components are denoted by the same reference numerals, and the description thereof is omitted.
[0058]
In general, when the operation time of the fuel cell stack becomes longer and the internal degradation of the fuel cell occurs, the cell voltage gradually decreases. For example, if the polymer membrane electrode catalyst composite is deteriorated, the gas flow path is clogged, or leaked, the cell voltage or the cell group voltage shows an abnormality. For this reason, it is necessary to determine the deterioration of individual cells or a plurality of cells.
[0059]
A feature of the second embodiment is that an output voltage from each cell or a plurality of cells constituting the fuel cell stack 15 is detected by the stack voltage sensor 35, and each cell voltage is detected by the fuel cell control device 51. Is to determine for all cells or groups whether or not is greater than a specified value.
[0060]
Next, the warning process at the time of deterioration of the stack cell by the fuel cell control device 51 will be described according to the flowchart shown in FIG. The control flowchart shown in FIG. 4 has the same basic procedure as the control flowchart shown in FIG. 2, and the same procedure is denoted by the same reference numeral. The control flowchart shown in FIG. 4 is also stored as a control program in the internal ROM of the fuel cell control device 51.
[0061]
In step S170, the voltage data of individual cells or a plurality of cells is read from the stack voltage sensor 35 provided in the fuel cell stack 15, and the cell number or group number is added to the voltage data to thereby control the fuel cell control device. This is stored in the internal RAM 51.
[0062]
In step S180, the voltage data stored in the internal RAM is sequentially read out in the order of cell number or group number, and it is determined for all cells whether each cell voltage is equal to or higher than a specified value. If all the cell voltages are equal to or higher than the specified value, the process is terminated.
[0063]
On the other hand, if the output voltage of one cell or cell group is less than the specified value, in step S190, the fuel cell or group has deteriorated, so the fuel cell or group is inspected or replaced. Is generated, converted into an audio signal by an audio generator (not shown), and output from the speaker.
[0064]
At this time, if the cell number or group number of the deteriorated fuel cell stack is notified, the work efficiency of inspection or replacement can be improved.
[0065]
In step S170, the voltage data of each cell or a plurality of cells is read from the stack voltage sensor 35, and the cell number or group number is added to the voltage data and stored in the internal RAM of the fuel cell control device 51. Then, after a predetermined unit time has elapsed, the same storage process is performed again, and further, in step S180, the cell voltage drop rate per unit time is obtained, and this cell voltage drop rate falls below the specified value. In such a case, a warning prompting the inspection or replacement of the fuel cell stack may be notified.
[0066]
As a result, as an effect related to the second embodiment of the present invention, when the output voltage of the fuel cell stack becomes a predetermined value or less, by notifying a warning prompting the inspection or replacement of the fuel cell stack, Even if the fuel cell stack has deteriorated for a long time, the vehicle can be operated with confidence until a warning is received, and when the warning is received, a service center can promptly check or replace the fuel cell stack. it can.
[0067]
In addition, since a warning that prompts inspection or replacement of the fuel cell stack is issued, the fuel cell stack can be protected from being damaged.
[0068]
Furthermore, since the output voltage is detected from individual cells or a plurality of cells constituting the fuel cell stack, a warning prompting the inspection or replacement of the fuel cell stack is notified for each or a plurality of cells. can do.
[0069]
(Third embodiment)
FIG. 5 is a diagram showing the configuration of a system to which the output diagnostic apparatus for a fuel cell vehicle according to the third embodiment of the present invention can be applied. The system configuration of this embodiment is obtained by adding new components to the basic configuration of the system corresponding to the first embodiment shown in FIG. 1, and the same components are denoted by the same reference numerals. The description thereof will be omitted.
[0070]
The feature of the third embodiment is that, in addition to the pressure sensor 41 and the temperature sensor 45 described above, the fuel cell stack 15 is a sensor that detects the cause of the cause that affects the drop in the output voltage of the fuel cell stack 15. And a CO concentration sensor 63 for detecting the CO concentration discharged from the fuel cell stack 15 as new components.
[0071]
Further, the fuel cell control device 71 stores in advance an internal ROM as a numerical table or a map in advance as the amount of decrease in the output voltage corresponding to the amount of change of each of the above-described cause amounts, and is detected by each of the above-described sensors. Based on the amount of change in the cause amount, the reference voltage drop amount at the normal time is read from the internal ROM, and the result amount obtained by subtracting from the actual drop amount of the output voltage detected by the stack voltage sensor 35 is equal to or greater than the specified value. If this amount is greater than or equal to the specified value, the cause of the drop in the output voltage of the fuel cell stack 15 is notified.
[0072]
Next, the warning process at the time of deterioration of the stack cell by the fuel cell control device 71 will be described according to the flowchart shown in FIG. The control flowchart shown in FIG. 6 has the same basic procedure as the control flowchart shown in FIG. 2, and the same procedure is denoted by the same reference numeral. 6 is stored in the internal ROM of the fuel cell control device 71 as a control program.
[0073]
In step S65, the detection values detected by the pressure sensor 41, the temperature sensor 45, the flow rate sensor 61, and the CO concentration sensor 63 are stored in the internal RAM.
[0074]
Here, in steps S70 and S80, as described above, the voltage data read from the stack voltage sensor 35 is stored in the internal RAM for a specified time.
[0075]
In step S90, as described above, the initial value and the current value are read from the output voltage data of the fuel cell stack 15 stored in the internal RAM of the fuel cell control device 51, and the output reduction rate% is calculated.
[0076]
In step S210, it is determined whether the output reduction rate is equal to or less than a specified value. Here, when the output decrease rate is equal to or less than the specified value, the current value of the output voltage output from the fuel cell stack 15 is not deteriorated with respect to the initial value, and the process is terminated.
[0077]
On the other hand, if the output reduction rate does not become the specified value or less, the fuel cell stack 15 has deteriorated, so the process proceeds to step S220 to generate warning message data that prompts inspection or replacement of the fuel cell stack 15, For example, it is converted into an audio signal by an audio generation unit (not shown) and output from a speaker.
[0078]
In step S230, the detection values detected by the pressure sensor 41, the temperature sensor 45, the flow sensor 61, and the CO concentration sensor 63 are stored in the internal RAM.
[0079]
In step S240, detection values separated by a specified time by each sensor are read from the internal RAM, and a change amount that is a difference value between the two detection values is calculated. Then, based on the amount of change in the detected value of each sensor, the reference voltage drop amount at the normal time is read from the numerical table or map stored in the internal ROM.
[0080]
As a result, a voltage drop amount ΔVi serving as a normal reference with respect to each change amount of the hydrogen gas pressure, temperature, hydrogen gas flow rate, and CO concentration is obtained.
[0081]
Here, in step S250, the actual drop amount ΔVr of the output voltage detected by the stack voltage sensor 35, the detection values detected by the pressure sensor 41, the temperature sensor 45, the flow sensor 61, and the CO concentration sensor 63 are obtained. Based on each normal voltage drop ΔVi,
[Expression 2]
ΔVr−ΔVi ≧ specified value
Judge whether or not.
[0082]
Here, when the subtraction result amount due to any one of the pressure sensor 41, the temperature sensor 45, the flow rate sensor 61, and the CO concentration sensor 63 is equal to or greater than a specified value, the process proceeds to step S260. On the other hand, if the subtraction result amount is less than the specified value, the process is terminated.
[0083]
In step S260, warning message data representing a possible cause location is generated based on the sensor mounting position and the detection target that caused the output voltage of the fuel cell stack 15 to drop. It converts into an audio signal and outputs from a speaker.
[0084]
For example, when an abnormality has occurred in the CO concentration detected by the CO concentration sensor 63, notification is made that the fuel reformer 11 that is reforming methanol, which is the fuel, with water should be repaired. Can do. Further, for example, when an abnormality occurs in the pressure of the reformed gas detected by the pressure sensor 41, it can be notified that the piping and the fuel reformer 11 should be repaired.
[0085]
As a result, as an effect related to the third embodiment of the present invention, it is possible to confirm the cause of the decrease in the output voltage of the fuel cell stack by notifying the cause of the decrease in the output voltage of the fuel cell stack. .
[0086]
Further, at least one of a flow rate of hydrogen gas flowing into the fuel cell stack, a CO concentration discharged from the fuel cell stack, a pressure of hydrogen gas flowing into the fuel cell stack, and a temperature of the fuel cell stack is detected. Therefore, it is possible to identify the cause of the drop in the output voltage of the fuel cell stack.
[Brief description of the drawings]
FIG. 1 is a diagram showing the configuration of a system to which an output diagnosis device for a fuel cell vehicle according to a first embodiment of the present invention can be applied.
FIG. 2 is a flowchart for explaining output correction control processing by a fuel cell control device 51;
FIG. 3 is a graph showing a hydrogen utilization rate table corresponding to an output decrease rate.
FIG. 4 is a flowchart for explaining warning processing when a stack cell is deteriorated by the fuel cell control device 51;
FIG. 5 is a diagram showing the configuration of a system to which an output diagnostic apparatus for a fuel cell vehicle according to a third embodiment of the present invention can be applied.
FIG. 6 is a flowchart for explaining warning processing at the time of deterioration of a stack cell by the fuel cell control device 71;
[Explanation of symbols]
11 Fuel reformer
13 Compressor
15 Fuel cell stack
17 Power distributor
19 Vehicle load
21 Secondary battery
23, 25, 31, 33 Pressure regulating valve
35 Stack voltage sensor
37 Stack current sensor
41 Pressure sensor
43 Pressure sensor
45, 47 Temperature sensor
51, 71 Fuel cell control device
53 Drive control device
55 Fixed resistance for discharge
57 switch
61 Flow sensor
63 CO concentration sensor

Claims (3)

In a fuel cell vehicle output diagnostic device for diagnosing the output state of a fuel cell for a fuel cell vehicle traveling by supplying power output from a fuel cell and a secondary battery to a drive motor,
Fuel cell control means for controlling the fuel cell to output a predetermined current to the secondary battery for a predetermined time after setting a predetermined operating condition with the temperature and pressure inside the fuel cell within the specified range when the vehicle is stopped; ,
An output voltage detecting means for detecting an output voltage output from the fuel cell;
Output voltage storage means for storing the output voltage of the fuel cell when the fuel cell control means performs control to output a predetermined current from the fuel cell for a predetermined time when the vehicle is stopped;
With respect to the output voltage of the fuel cell, a calculation means for calculating an output decrease rate by comparing a current value that is the latest value stored in the output voltage storage means with an initial value stored in advance.
An output diagnostic apparatus for a fuel cell vehicle, comprising: correction means for correcting the maximum power that can be output from the fuel cell in accordance with an output reduction rate. Output voltage determination means for determining whether the output voltage of the fuel cell detected by the output voltage detection means is a predetermined value or less;
2. The fuel cell vehicle according to claim 1, further comprising a notifying means for notifying a warning prompting the inspection or replacement of the fuel cell when the output voltage output from the fuel cell becomes a predetermined value or less. Output diagnostic device. The output voltage detection means includes
3. The output diagnosis apparatus for a fuel cell vehicle according to claim 2, wherein the output voltage is detected from individual cells or a plurality of cells constituting the fuel cell.

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