JP4404584B2 - Fuel cell system - Google Patents

Description

  The present invention relates to a fuel cell system that can cope with an operating life or gas leakage.

In a conventional solid polymer fuel cell, hydrogen (H ₂ ) supplied to the fuel electrode (anode electrode) is decomposed into hydrogen ions (H ⁺ ) and electrons (e ⁻ ), and the hydrogen ions are solid polymer. It passes through the membrane (electrolyte) and moves to the air electrode (cathode electrode). On the other hand, electrons are generated by flowing through an external circuit, and move to the air electrode. Solid polymer fuel cells are easy to handle because the polymer electrolyte membrane is not liquid like phosphoric acid fuel cells, and the reaction temperature is as low as 100 ° C. .

  However, on the other hand, as the solid polymer membrane that is an electrolyte, a film-like ion exchange membrane is generally used, but there is a problem in terms of strength and durability. In other words, solid polymer membranes are not as strong and durable as non-solid polymer fuel cells, and pinholes may open in the membrane or the membrane may break due to deterioration or lifetime due to the properties of the membrane. There are things to do. When a hole is formed in the solid polymer membrane, not only hydrogen ions but also hydrogen itself partially flows from the anode electrode (negative electrode) to the cathode electrode (positive electrode) (referred to as cross-leakage phenomenon), and the off-gas at the cathode electrode becomes hydrogen. It is known that there is a possibility of being released to the outside in a state of being mixed. However, it is not easy to accurately predict the cross leak, and when the cross leak occurs, there is a risk of ignition or the like due to the mixture of air (oxygen) and hydrogen.

  Accordingly, the present invention provides a fuel cell system that can be operated safely by predicting that the operating life has been reached in advance, or by predicting cross leak in advance or detecting cross leak. With the goal.

In order to achieve the above object, the fuel cell system 1 according to the first aspect of the invention generates power by an electrochemical reaction between the fuel gas h1 and the oxidant gas k1, as shown in FIGS. 1 and 2, for example. A fuel cell system 1 comprising: a fuel cell main body 2; an operation time measuring means 11 for measuring the cumulative operation time of the fuel cell main body 2, or an operation frequency measuring means 12 for measuring the cumulative operation frequency of the fuel cell main body 2. If the fuel cell system 1 includes the operation time measuring means 11, the fuel cell system 1 is controlled to stop when the measured operation time reaches a first predetermined value set in advance. When the fuel cell system 1 includes the operation number measuring means 12, the fuel cell system 1 is not activated next time when the measured operation number reaches a second predetermined value set in advance. Further comprising a control unit 7 for controlling so.

  If comprised in this way, since the fuel cell main body 2, the operation time measurement means 11 or the operation frequency measurement means 12, and the control means 7 are provided, the operation time measured by the operation time measurement means 11 is preset. The fuel cell system 1 is stopped when the predetermined value of 1 is reached, and the fuel cell system 1 is stopped when the number of operations measured by the operation number measuring means 12 reaches a second predetermined value set in advance. It can be controlled by the control means 7 so as not to be started next time, and it can be predicted that the fuel cell system 1 will reach the operating life, stop or avoid the next start, and the fuel cell system 1 can be operated safely. .

In order to achieve the above object, the fuel cell system 1 according to the second aspect of the invention generates power by an electrochemical reaction between the fuel gas h1 and the oxidant gas k1, as shown in FIGS. 1 and 2, for example. A fuel cell system comprising: a fuel cell main body 2; an operation time measuring means 11 for measuring the cumulative operation time of the fuel cell main body 2, and an operation frequency measuring means 12 for measuring the cumulative operation frequency of the fuel cell main body 2. The fuel cell system 1 is stopped when the total of the measured operation time and the value obtained by converting the measured number of operations into the operation time reaches a preset third predetermined value. Or the sum of the measured number of operations and the value obtained by converting the measured operation time into the number of operations reaches the fourth predetermined value set in advance. Next time Further comprising a control unit 7 for controlling No matter.

  If comprised in this way, since the fuel cell main body 2, the operation time measurement means 11, the operation frequency measurement means 12, and the control means 7 are provided, the operation time measured by the operation time measurement means 11 and the operation frequency measurement. The fuel cell system 1 is stopped when the sum of the operation count measured by the means 12 and the value converted into the operation time reaches a preset third predetermined value, or the measured operation count and the measurement The fuel cell system 1 can be controlled by the control means 7 so that the fuel cell system 1 is not started next time when the sum of the calculated number of operations and the value converted into the operation time reaches a preset fourth predetermined value. The fuel cell system 1 can be safely operated by predicting that the battery system 1 will reach the operating life more accurately and stopping or avoiding the next activation.

The fuel cell system 1 according to the third aspect of the invention is similar to the fuel cell system 2 of the first or second aspect , as shown in FIGS. 1 and 2, for example, with the fuel cell body 2 on the cathode side. A detector 10 for detecting the concentration of hydrogen gas contained in the cathode offgas k2 is provided in the vicinity of the exhaust port 24 for exhausting the cathode offgas k2, and the detector 10 has a concentration equal to or higher than a fifth predetermined value. When it is detected, the control means 7 controls the fuel cell system 1 to stop.

  If comprised in this way, since the detection means 10 is provided, when the detection means 10 detects that the density | concentration of the hydrogen gas contained in the cathode offgas k2 is more than a 5th predetermined value, the control means 7 will be fuel. It is possible to control the battery system 1 to stop, cope with the occurrence of gas leakage of hydrogen gas to the cathode offgas k2, and operate the fuel cell system 1 safely.

The fuel cell system 1 according to the fourth aspect of the invention is the fuel cell system according to any one of the first to third aspects . For example, as shown in FIG. 1 and FIG. When the control is performed so that the fuel cell system 1 is stopped and the fuel cell system 1 is stopped, or when the control means 7 performs the control so that the fuel cell system 1 is not started next time, an instruction signal i18 for instructing maintenance , I20, i16 are provided with instruction signal output means 7.

According to this structure, since provision of an indicator signal output means 7, the first time reaches a predetermined value or operation time measurement means 11, for example has been operation time measured by the operation time measuring means 11 has been set in advance When the sum of the measured operation time and the value obtained by converting the operation frequency measured by the operation frequency measurement means 12 into the operation time reaches a preset third predetermined value or when the detection means 10 is the cathode When it is detected that the concentration of hydrogen gas contained in the off-gas k2 is equal to or higher than a fifth predetermined value, the control means 7 controls the fuel cell system 1 to stop or is measured by, for example, the operation number measuring means 12 when been operating frequency reaches a second predetermined value set in advance, or the operating frequency measured by the operating frequency measuring means 12, operation time measurement When it reaches the fourth predetermined value sum of the value obtained by converting the number operated by the operation time measured by the stage 11 is set in advance, the control unit 7, the fuel cell system 1 so as not to start the next time the When the control is performed, the instruction signal output means 7 can output the instruction signals i18, i20, i16 instructing the maintenance, and the maintenance of the fuel cell system 1 can be performed.

The fuel cell system 1 according to the fifth aspect is the fuel cell system according to any one of the first to fourth aspects . In the fuel cell system 1 according to the fifth aspect , for example, as shown in FIGS. When the control is performed to stop the fuel cell system 1 and the fuel cell system 1 is stopped, or when the control means 7 performs the control not to start the fuel cell system 1 next time, a display for instructing maintenance is performed. Instruction display means 13, 33, 34 are provided.

If comprised in this way, since the instruction | indication display means 13,33,34 is provided, when the driving | running time measured by the driving | running time measurement means 11 , for example reaches the preset 1st predetermined value, or driving | running time measurement When the sum of the operation time measured by the means 11 and the value obtained by converting the operation frequency measured by the operation frequency measurement means 12 into the operation time has reached a preset third predetermined value, or detection means When the controller 10 detects that the concentration of hydrogen gas contained in the cathode offgas k2 is equal to or higher than a fifth predetermined value, the control means 7 controls the fuel cell system 1 to stop, or, for example, the operation frequency measuring means when the operating frequency measured by the 12 reaches the second predetermined value set in advance, and operating frequency measured by the operating frequency measuring means 12, operation time meter When it reaches the fourth predetermined value sum is preset to a value obtained by converting the number operated by the operation time measured by the unit 11, the control so that the control unit 7 does not activate the fuel cell system 1 next And a display for instructing maintenance is performed by the instruction display means 13, 33, 34, and the maintenance of the fuel cell system 1 can be performed.

As described above, according to the present invention, the fuel cell main body, the operation time measurement means or the operation frequency measurement means, and the control means are provided. Therefore, when the fuel cell system includes the operation time measurement means, the operation time measurement means If the fuel cell system is stopped when the measured operation time reaches a first predetermined value set in advance, and the fuel cell system includes an operation time measurement means, the number of operations measured by the operation number measurement means Can be controlled by the control means 7 so that the fuel cell system is not started next time when the value reaches a preset second predetermined value, and it is predicted that the fuel cell system has reached the operating life. The system can be operated safely.
As described above, according to the present invention, since the fuel cell main body, the operation time measuring means, the operation number measuring means, and the control means are provided, the operation time measured by the operation time measuring means and the operation number measuring means are provided. The fuel cell system is stopped when the sum of the operation number measured by the value converted into the operation time reaches a third predetermined value set in advance, or the measured operation number and the measured operation The fuel cell system can be controlled by the control means so that the fuel cell system is not started next time when the sum of the number of times converted into the operation time reaches a preset fourth predetermined value, and the fuel cell system is more accurate. The fuel cell system can be safely operated by predicting that the operating life is often reached and stopping or avoiding the next start-up.

Embodiments of the present invention will be described below with reference to the drawings.
1 and 2 are block diagrams showing a configuration of a fuel cell system 1 according to an embodiment of the present invention.
A fuel cell system 1 (hereinafter referred to as system 1) includes a polymer electrolyte fuel cell main body 2 (hereinafter referred to as fuel cell main body 2), a hydrogen cylinder 3 serving as a hydrogen gas supply device, an open / close solenoid valve 4 for fuel gas, An air blower device 5 that is an air supply device, a humidifying device 6, a control device 7, a DC power relay 8, an off-gas open / close electromagnetic valve 9, a gas detector 10 as a detecting means, and an operating time measuring means. An integrating hour meter 11, an operation counter 12 as an operation count measurement means, a stop display section 13 as an instruction display means, a stop display section 33 as an instruction display means, and a non-activation display section 34 as an instruction display means A pressure gauge 14, a flow meter 15, an output circuit 16, and a voltmeter 17.

  The fuel cell main body 2 includes an anode introduction port 21 for introducing hydrogen gas h1 as a fuel gas into the anode electrode, and a cathode introduction port 22 for introducing air k1 as an oxidant gas into the cathode electrode. AC power is generated by an electrochemical reaction between h1 and oxygen in the introduced air k1. The fuel cell body 2 further includes an anode exhaust port 23 for exhausting the anode off gas h2 from the anode electrode, and a cathode exhaust port 24 as an exhaust port for exhausting the cathode off gas k2 from the cathode electrode.

  The fuel cell main body 2 is further connected to a fuel supply line 25 that connects the hydrogen cylinder 3 and the anode inlet 21, an oxidant gas supply line 26 that connects the air blower device 5 and the cathode inlet 22, and an anode exhaust port 23. An anode offgas line 27 and a cathode offgas line 28 connected to the cathode exhaust port 24.

  The hydrogen cylinder 3 is filled with hydrogen gas h 1 and supplies the hydrogen gas h 1 to the anode inlet 21. The fuel supply line 25 is opened to supply the pressure gauge 14 for measuring the supply pressure of the hydrogen gas h1 and the hydrogen gas h1 to the fuel cell main body 2, and does not supply the hydrogen gas h1 to the fuel cell main body 2. Therefore, the fuel gas on-off solenoid valve 4 to be closed is installed in this order with respect to the flow of the hydrogen gas h1. The pressure gauge 14 sends a pressure signal i1 (B in FIG. 1) representing the measured supply pressure of the hydrogen gas h1 to the control device 7. The fuel gas open / close solenoid valve 4 is opened / closed by an open signal i2 (D in FIG. 1) sent from the control device 7.

  The air blower device 5 includes an air blower 5A and a motor (not shown) that drives the air blower 5A, and supplies air k1 in the atmosphere to the cathode inlet port 22. In the oxidant gas supply line 26, a flow meter 15 for measuring the supply amount of the air k1 and a humidifier 6 for humidifying the air k1 are installed in this order with respect to the flow of the air k1. A motor (not shown) of the air blower device 5 is driven by a drive signal i3 (A in FIG. 1) sent from the control device 7. The humidifier 6 is driven by a drive signal i13 (E in FIG. 1) sent from the controller 7. The flow meter 15 sends a flow rate signal i4 (C in FIG. 1) representing the measured flow rate of the air k1 to the control device 7. The humidifying device 6 includes a method of humidifying by heating pure water (electrically humidifying), a method of exchanging membranes using wet cathode offgas and drain water condensed there (mechanical membrane humidification), and the like. Yes, the humidity of the air k1 supplied to the fuel cell main body 2 is humidified so as to be almost 100%.

  The anode off gas line 27 is provided with an off gas on-off solenoid valve 9 that opens when the anode off gas h2 is discharged and closes when the anode off gas h2 is not discharged. The off-gas open / close solenoid valve 9 is opened by an open signal i5 (F in FIG. 1) sent from the control device 7.

The cathode offgas line 28 measures the concentration of hydrogen gas in the cathode offgas k2, and the measured concentration of hydrogen gas is a set concentration (fifth predetermined value) (for example, 1%, ignition of hydrogen in air). Since the lower limit (LEL) is 4%, the gas detector 10 that sends the gas detection signal i6 (G in FIG. 1) to the control device 7 when this 1% exceeds the 25% LEL level. is set up. The gas detector 10 is disposed in the vicinity of the cathode exhaust port 24.
The gas detector 10 measures the concentration of hydrogen gas in the cathode offgas k2, sends a signal (not shown) indicating the measured concentration of hydrogen gas to the control device 7, and the control device 7 sets the concentration of hydrogen gas to the set concentration. You may make it judge whether it is above. In this case, the gas detector 10 and the control device 7 are detection means of the present invention.

  The fuel cell main body 2 includes an anode output end 29 and a cathode output end 30. The output circuit 16 includes an anode external output terminal 31 and a cathode external output terminal 32, the negative side is connected to the anode output terminal 29, and the positive side is connected to the cathode output terminal 30. On the plus side of the output circuit 16, there is a voltmeter 17 that measures the output voltage of the fuel cell body 2, and a DC that closes the output circuit 16 so that the power generated by the fuel cell body is output to a load (not shown). A power relay 8 is connected. The voltmeter 17 sends a voltage signal i7 (H in FIG. 1) representing the measured output voltage of the fuel cell main body 2 to the control device 7. The DC power relay 8 closes the output circuit 16 so that the generated power is output to the load (not shown) by the power generation output signal i8 (I in FIG. 1) from the control device 7, and the load and fuel The battery body 2 is electrically connected.

  The operation counter 12 receives an operation start signal i9 indicating that the operation of the fuel cell main body 2 has started from the control device 7, and accumulates and accumulates the operation counts (sets the operation count to 1). The operation counter 12 sends an operation frequency signal i10 indicating the integrated operation frequency to the control device 7, and the control device 7 stores this value. Prior to the start of operation of the fuel cell main body 2, the control device 7 stores the number of operations until the previous time, and an operation start signal i9 indicating that the operation counter 12 has started operation of the fuel cell main body 2 from the control device 7. When the operation number is accumulated and accumulated, that is, when the operation number is incremented by 1, the operation number signal i10 is received, and the stored operation number and the new operation number are exchanged and stored.

  The integrating hour meter 11 receives an operation start signal i9 indicating that the operation of the fuel cell main body 2 has started from the control device 7, starts accumulating the operation time, and starts the operation of the system 1 from the control device 7. The operation stop signal i11 indicating that the operation of the fuel cell main body 2 is ended is received, and the integration of the operation time is ended. The accumulated hour meter 11 sends an accumulated time signal i12 representing the accumulated operation time to the control device 7 during the accumulation of the operation time.

  After the fuel cell main body 2 is started, the control unit 7 controls the system 1 to stop when the integrated operation time indicated by the integration time signal i12 sent by the integration time meter 11 exceeds a preset set time. When the system 1 is stopped, the stop display unit 13 receives the display signal i19 issued from the control device 7, displays that the system 1 has been forcibly stopped because the operating life has passed, and also provides maintenance instructions. Is displayed.

  After the fuel cell main body 2 is activated, the stop display unit 33 receives a gas detection signal i6 from the gas detector 10, and the concentration of hydrogen gas in the cathode offgas k2 exceeds a preset concentration, and the control device 7 Controls the system 1 to stop, and when the system 1 stops, the display signal i21 issued from the control device 7 is received, and the system 1 is forced because the hydrogen gas in the cathode offgas k2 exceeds the set concentration. And a maintenance instruction is displayed.

  The non-activation display unit 34 displays a display issued from the control device 7 when the fuel cell main body 2 is not activated because the accumulated number of operations has reached a preset number of times after the activation command is issued. In response to the signal i17, the system 1 indicates that the fuel cell main body 2 is not started because the operating life has passed, and also displays a maintenance instruction.

  The control device 7 receives an activation command signal i14 for instructing activation of the system 1 from the outside. The control device 7 that has received the start command signal i14 compares the number of operations stored in the control device (the number of operations during the previous operation) with a preset number of times, and the number of operations reaches the set number of times. In such a case, control is performed so that the fuel cell main body 2 is not activated. In this case, next, the control device 7 outputs a system non-start signal i16 as an instruction signal indicating that the system 1 does not start because the operating life has passed, and outputs the display signal i17 to the non-start display unit 34. The system 1 indicates that the system 1 has not been activated because the operating life has passed, and displays the non-activation display unit 34 indicating a maintenance instruction.

  The control device 7 that has received the activation command signal i14 activates the fuel cell main body 2 as follows when the number of operations has not reached the set number. The control device 7 sends an open signal i2 for opening the fuel gas on-off solenoid valve 4 to the fuel gas on-off solenoid valve 4, opens the fuel gas on-off solenoid valve 4, supplies hydrogen gas h1, and drives the drive signal. i3 is sent to the air blower device 5 to drive the air blower 5A to supply air k1, and the drive signal i13 is sent to the humidifier 6 to drive the humidifier 6 to humidify the air k1. When the hydrogen gas h1 is introduced, the off-gas opening / closing solenoid valve 9 is opened, and after a predetermined time (for example, 5 seconds), the off-gas opening / closing solenoid valve 9 is closed, the power generation of the fuel cell body 2 is started, and the fuel cell body 2 When the voltage of power to be generated decreases (for example, 70% or less of the rated voltage), the off-gas open / close solenoid valve 9 is opened, the anode off-gas h2 is exhausted from the anode electrode, and the hydrogen gas h1 is supplied to the anode electrode. . Then, after a certain time (for example, after 1 second), the off-gas opening / closing solenoid valve 9 is closed, and then the opening / closing of the off-gas opening / closing solenoid valve 9 is repeated.

  Further, when the control device 7 receives a stop command signal i15 for instructing the stop of the system 1 after the system 1 is started up, the control device 7 stops the system 1 as follows. The control device 7 stops sending an open signal i2 for opening the fuel gas open / close solenoid valve 4 to the fuel gas open / close solenoid valve 4, closes the fuel gas open / close solenoid valve 4, and supplies hydrogen gas h1. , Stop sending the drive signal i3 to the air blower device 5, stop driving the air blower 5A, stop supplying the air k1, stop sending the drive signal i13 to the humidifier 6, and the humidifier 6 is stopped, and humidification of the air k1 is stopped.

  The control device 7 receives a pressure signal i 1 from the pressure gauge 14, a flow signal i 4 from the flow meter 15, a gas detection signal i 6 from the gas detector 10, and a voltage signal i 7 from the voltmeter 17. When the voltage value of the electric power generated by the fuel cell body 2 indicated by the voltage signal i7 becomes lower than a predetermined value (for example, 70% of the rated voltage value) during the power generation of the fuel cell body 2, the control device 7 Then, the open signal i5 is sent to the off-gas open / close solenoid valve 9, and the off-gas open / close solenoid valve 9 is opened. When the off-gas opening / closing solenoid valve 9 is opened, the hydrogen gas h1 is introduced into the anode inlet 21 and the voltage value of the electric power generated by the fuel cell main body 2 increases. Then, after a certain time (for example, after 1 second), the sending of the open signal i5 to the off-gas open / close solenoid valve 9 is stopped, and the off-gas open / close solenoid valve 9 is closed. When the off-gas opening / closing solenoid valve 9 is closed, the introduction of the hydrogen gas h1 into the anode introduction port 21 is stopped, and the voltage value of the electric power generated by the fuel cell main body 2 is lowered. Thereafter, the above control is repeated.

  After the fuel cell main body 2 is started, that is, an open signal i2 for opening the fuel gas open / close solenoid valve 4 is sent to the fuel gas open / close solenoid valve 4, and a drive signal i3 for driving the air blower 5A is sent to the air blower device 5, After the driving signal i13 for driving the humidifying device 6 is sent to the humidifying device 6, the control device 7 sends the operation start signal i9 to the integrating hour meter 11 and the operation counter 12, and after the system 1 stops, the operation stop signal i11. Is sent to the total time meter 11. When the accumulated time signal i12 is sent from the accumulated time meter 11, the control device 7 compares the accumulated operation time indicated by the accumulated time signal i12 with a preset set time, and the operation time becomes equal to or greater than the set time. If this happens, the system 1 is forcibly stopped. In this case, next, the control device 7 outputs a system stop signal i18 as an instruction signal indicating that the system 1 has been forcibly stopped because the operating life has elapsed, and outputs a display signal i19 to the stop display unit 13. In addition to indicating that the system 1 has been forcibly stopped because the operating life has passed, a display of the stop display unit 13 indicating a maintenance instruction is performed. The display signal i19 is output from, for example, a no-voltage or positive-voltage contact output (not shown), an open collector output (not shown) of a transistor, or a communication output (not shown) such as RS, which is provided in the control device 7. It is good also as a thing. Further, the stop display unit 13 may display a display unit on which a maintenance character is written by turning on / off a light.

  The control device 7 determines whether or not the gas detection signal i6 is sent from the gas detector 10, and when the gas detection signal i6 is sent, the system 1 is forcibly stopped. In this case, next, the control device 7 outputs a system stop signal i20 as an instruction signal indicating that the system 1 has been forcibly stopped because the operating life has passed, and displays the display signal i21 as a stop display unit 33. In addition to indicating that the system 1 has been forcibly stopped because the operating life has passed, a display of the stop display unit 33 indicating a maintenance instruction is displayed.

Next, the control method of the fuel cell system 1 by the control device 7 of the present embodiment will be described with reference to FIG. 3 and with reference to FIGS. 1 and 2 as appropriate.
It is determined whether or not there is a start command by sending the start command signal i14 to the control device 7 (step S1). When there is no start command (when step S1 is NO (hereinafter, N)), the fuel cell body 2 is not started (step S2). If there is a start command (when step S1 is YES (hereinafter, Y)), has the number of operations accumulated by the operation counter 12 reached a set number (second predetermined value) (for example, 1000)? It is determined whether or not (step S3). When the number of operations reaches the set number (when step S3 is Y), the fuel cell main body 2 is not activated (step S4), and the control device 7 outputs a non-activation signal i16 as a non-activation output to the outside. (Step S5) Further, the non-activation display unit 34 is turned on and non-activation display is performed (Step S6).

  Next, when the number of operations has not reached the set number (when step S3 is N), the fuel cell main body 2 is activated (step S7). That is, the open signal i2 is sent to the fuel gas open / close solenoid valve 4, the fuel gas open / close solenoid valve 4 is opened, the open signal i5 is sent to the offgas open / close solenoid valve 9, and the offgas open / close solenoid valve 9 is opened to generate hydrogen. The gas h1 is supplied, the drive signal i3 is sent to the air blower device 5, the air blower 5A is driven to supply the air k1, the drive signal i13 is sent to the humidifier 6, and the humidifier 6 is driven to humidify the air k1.

Next, it is determined whether power generation is possible (step S7A). Specifically, whether the supply pressure of the hydrogen gas h1 indicated by the pressure signal i1 from the pressure gauge 14 is within a predetermined pressure range (0.1 to 0.2 MPa) (condition 1), or the flow signal i4 from the flowmeter 15 It is determined whether the air supply amount indicated by is equal to or greater than a predetermined flow rate value (no load, for example, 0.5 Nm ³ / hr) (condition 2). When these two conditions are not satisfied (when step S7A is N), an alarm (step S8) is issued and the fuel cell main body 2 is stopped (step S9). That is, the sending of the open signal i2 to the fuel gas on-off solenoid valve 4 is stopped, the fuel gas on-off solenoid valve 4 is closed, the supply of the hydrogen gas h1 is stopped, and the drive signal i3 is sent to the air blower device 5. The air blower is stopped, the supply of air k1 is stopped, the drive signal i13 is stopped from being sent to the humidifier 6, the humidifier 6 is stopped, and the humidification of the air k1 is stopped.

  When the two conditions are satisfied (when step S7A is Y), the operation start signal i9 is sent to the integrating hour meter 11 and the operation counter 12, and the integration by the integrating hour meter 11 is started (step S10). A calculation for adding 1 to the number of operations is performed by the counter 12 (step S11).

  Next, it is determined whether or not the operation time has reached a set time (first predetermined value) (eg, 3000 hours) (step S12). If the operation time has reached the set time (step S12 is Y In the case of (1), the system 1 is forcibly stopped due to the service life (step S13). The content of step S13 is the same as step S9 described above.

  When the system 1 is stopped, simultaneously with step S13, the system 1 is forcibly stopped due to its life and a system stop signal i18 indicating a maintenance instruction is output to the outside (step S14), and the system 1 is forcibly stopped due to its life. And a display signal i19 indicating a maintenance instruction is sent to the system stop display 13, the system stop display 13 is turned on (step S15), and the process proceeds to step S24 described later.

If the operating time has not reached the set time (when step S12 is N), then the gas concentration of the hydrogen gas in the cathode offgas k2 is equal to or higher than the set concentration ( fifth predetermined value) (for example, 1%). Whether or not the gas detection signal i6 from the gas detector 10 is output (step S16). If the gas concentration is equal to or higher than the set concentration (if step S16 is Y), the system 1 Is forcibly stopped due to gas leakage (step S17). The content of step S17 is the same as step S9 described above.

  When the system 1 is stopped, a system stop signal i20 indicating that the system 1 has been forcibly stopped due to gas leakage is output to the outside (step S18), indicating that the system 1 has been forcibly stopped due to its life and a maintenance instruction. The display signal i21 is sent to the stop display unit 33, the stop display unit 33 is turned on (step S19), and the process proceeds to step S24 described later.

  When the gas concentration in the cathode off gas k2 is less than the set concentration (when step S16 is N), it is determined whether or not power generation is in progress (step S20). When power generation is not in progress (step S20 is N), power generation is started (step S21), that is, a power generation output signal i8 is sent to the DC power relay 8, the output circuit 16 is closed, and power is loaded (not shown). Is returned to step S12, and the process proceeds to step S12.

  When power generation is in progress (step S20 is Y), it is determined whether or not there is a stop command by sending a stop command signal i15 to the control device 7 (step S22). When there is no stop command (when step S22 is N), the system 1 returns to step S12 without stopping, and proceeds to step S12. When there is a stop command (when step S22 is Y), the system 1 is stopped (step S23), an operation time stop signal i11 is sent to the integrated hour meter 11, and the integrated hour meter 11 ends the integration (step). S24). Note that the content of step S23 is the same as step S9 described above.

  In addition, when the system 1 is forcibly stopped due to the operation time reaching the set time, when the system 1 is started and stopped due to the operation frequency reaching the set number of times, and the gas concentration has reached the set concentration. Thus, when the system 1 is started and stopped and the necessary maintenance of the system 1 is performed, both the operation time and the number of operations are reset to 0 before the operation of the system 1.

In the polymer electrolyte fuel cell main body 2, hydrogen ions (H ⁺ ) of the hydrogen gas introduced from the anode introduction port 21 to the anode electrode (positive electrode) are in a solid state between the anode electrode and the cathode electrode (negative electrode). Electricity is generated by passing through the molecular film while electrons (e ⁻ ) flow between the electrodes. A solid polymer film may have pinholes in the film or may be broken due to deterioration or longevity of the film due to the characteristics of the film. When a hole is formed in the solid polymer membrane, not only hydrogen ions but also hydrogen (H ₂ ) itself partially flows from the anode electrode to the cathode electrode (cross leak), and the cathode off-gas discharged from the cathode exhaust port 24 There is a possibility that h2 flows through the cathode offgas line 28 in a state in which hydrogen gas exceeding the dangerous concentration is mixed.

  If the number of operations reaches the set number of times, the solid polymer membrane (not shown in Fig. 1) is considered to have deteriorated due to its life and there is a risk of cross-leakage. When the time has been reached, control is performed so that the operation of the system 1 is stopped in the same manner, and maintenance (for example, replacement of the fuel cell body, etc.) is performed both before the next start and after the current stop. In addition, if for some reason a cross leak occurs due to deterioration of the solid polymer film before the number of operations reaches the set number of times or before the operation time reaches the set time, the concentration of hydrogen gas in the cathode off gas h2 This cross leak is detected by measuring and control is performed to stop the operation of the system 1, and maintenance is performed after the stop. Therefore, it is possible to appropriately cope with the cross leak of the system 1 and to operate the system 1 safely.

In FIG. 2, as another embodiment, the control device 7 may store the accumulated operation time indicated by the accumulated time signal i <b> 12 sent from the accumulated hour meter 11. In such a case, when the control device 7 stops the system 1, the control device 7 stores the operation time up to the previous time. The operation number N stored in the control device 7 (the number of operations until the previous time) (unit, time) and the operation time T ₁ stored in the control device 7 (the operation time up to the previous time) (unit, time) ) 'in terms of an operating frequency _{N 1} operating frequency _{N 1'} operating frequency _{N 1} of the group total _N 10 a _{(= N 1 + N 1 '} ) and may be for controlling the above. The conversion may be, for example, N ₁ ′ = 0.1 × T ₁ . In this case, for example, to perform one operation of 10 hours, the number of operations N ₁₀ total becomes twice, set number (predetermined value of the fourth), for example, or equal to 1000 times. ).

Alternatively, the control device 7, the operation time T ₂ of the accumulated time signal i12 is integrated indicating sent from the integration time meter 11, the operating frequency N ₂ the operating frequency signal i10 is integrated indicating sent from operating frequency meter 12 The above-described control may be performed based on the total T ₂₀ (= T ₂ + T ₂ ′) with the value converted into the operation time T ₂ ′. The conversion may be, for example, T ₂ ′ = 10 × N ₂ . In this case, for example, to perform one operation of 10 hours, since the operation time T ₂₀ of the total of 20 hours, the set time (third predetermined value), for example, or equal to 3000 hours.

  In the case of the other embodiment described above, in FIG. 3, in step S3 and step S11, the number of operations is integrated with the number of operations measured by the operation counter and stored by the control device 7 (FIG. 2). The total number of operations. In step S <b> 12, the operation time is the sum of the operation time accumulated by the accumulation hour meter 11 and the operation time converted from the operation number accumulated by the operation counter 12.

  In the other embodiments as described above, the lifetime can be predicted more accurately.

1 is a block diagram showing a configuration of a fuel cell system according to an embodiment of the present invention. FIG. 2 is a block diagram showing signal input / output of the control device of the fuel cell system of FIG. 1. It is a sequence diagram which shows the control method by the control apparatus of the fuel cell system of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fuel cell system 2 Fuel cell main body 7 Control apparatus (control means) (instruction signal output means)
10 Gas detector (detection means)
11 Accumulated hour meter (operating time measuring means)
12 Operation counter (operation frequency measurement means)
13 Stop display section (instruction display means)
24 Cathode exhaust port (exhaust port)
33 Stop display section (instruction display means)
34 Non-activation display section (instruction display means)
h1 Hydrogen gas (fuel gas)
h2 Anode off - gas i16 non-start signal (instruction signal)
i18 System stop signal (instruction signal)
i20 System stop signal (instruction signal)
k1 air (oxidant gas)
k2 Cathode off gas

Claims (4)

A fuel cell body that generates electricity by an electrochemical reaction between the fuel gas and the oxidant gas;
An operation time measuring means for measuring a cumulative operation time of the fuel cell main body;
A fuel cell system comprising an operation frequency measuring means for measuring the cumulative operation frequency of the fuel cell main body;
Control is performed so that the fuel cell system is stopped when the sum of the measured operation time and the value obtained by converting the measured number of operations into the operation time reaches a preset third predetermined value. And
Alternatively, the fuel cell system is not activated next time when the total of the measured number of operations and the value obtained by converting the measured operation time into the number of operations reaches a preset fourth predetermined value. Further comprising control means for controlling;
Fuel cell system. A detection means for detecting the concentration of hydrogen gas contained in the cathode offgas, in the vicinity of an exhaust port for exhausting the cathode offgas, which the fuel cell body has on the cathode electrode side;
When the detection means detects that the concentration is equal to or higher than a fifth predetermined value, the control means controls to stop the fuel cell system;
The fuel cell system according to claim 1 . When the control unit performs the control to stop the fuel cell system and the fuel cell system stops, or when the control unit performs the control to prevent the fuel cell system from starting next time, the maintenance unit is instructed. An instruction signal output means for outputting an instruction signal;
The fuel cell system according to claim 1 or 2 . When the control unit performs the control to stop the fuel cell system and the fuel cell system stops, or when the control unit performs the control to prevent the fuel cell system from starting next time, the maintenance is instructed. An instruction display means for performing display to be performed;
The fuel cell system according to any one of claims 1 to 3 .

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