JP2002352839A - Protective stop controlling device for fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a protective stop controlling device which suppresses falling of the function of a fuel cell to minimum at protective stopping of a fuel cell system, with no extra new component. SOLUTION: An abnormal detecting part 2 of a protective stop controlling device 1 detects abnormal condition of a fuel cell main body and an auxiliary unit. A stop mode selecting part 3 selects any one stop mode from among a system total stop mode, a gas control stop mode, a power generation emergency stop mode, and a power generation normal stop mode, according to the information detected with the abnormal detecting part 2. A stop controlling part 4 stops the fuel cell system according to a selected stop mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell system, and more particularly to, when an abnormality of a fuel cell system is detected, stopping a fuel cell system by selecting a stop mode corresponding to abnormality detection information from a plurality of preset stop modes. The present invention relates to a protection stop control device for a fuel cell system that can be used.

[0002]

2. Description of the Related Art In a fuel cell, a fuel gas such as a hydrogen gas and an oxidizing gas containing oxygen are electrochemically reacted via an electrolyte to directly extract electric energy from between electrodes. FIG. 6 is a configuration diagram of a typical fuel cell electric vehicle using a fuel cell system as a main energy source.

In FIG. 6, a fuel cell 101 supplies generated DC power to an inverter 103,
Numeral 03 converts DC power into AC power to drive the vehicle driving AC motor 104, and the driving force generated by the AC motor 104 is transmitted to the driving wheels 106 via the differential device 105.

The hydrogen electrode of the fuel cell 101 is supplied with hydrogen from a high-pressure hydrogen cylinder 112 via a pressure regulating valve 134, and the air electrode is supplied with air from a compressor 114. The hydrogen and air are humidified by a humidifier 111. Is done. Humidifier 11
1 is supplied with pure water for humidification by a pure water supply pump 113. From the air electrode of the fuel cell 101, the air pressure regulating valve 1
Air is discharged through 33 to maintain the air pressure at the air electrode in an appropriate range.

[0005] The fuel cell 101 is cooled by cooling water supplied by a cooling water supply pump 115 driven by the fuel cell vehicle control device 121. The cooling water is
Cooled by radiator 116. The fuel cell vehicle control device 121 includes an accelerator sensor 122, a vehicle speed sensor 12
3. Brake sensor 124 and shift switch 125
To control the entire vehicle.

An air mass flow sensor 131 is provided at the inlet of the compressor 114, an air pressure sensor 132 is provided at the air electrode inlet of the fuel cell 101, a hydrogen pressure sensor 135 is provided at the hydrogen electrode inlet, and a cooling water temperature sensor is provided at the cooling water outlet. 136 are installed, and the fuel cell vehicle control device 121 reads the values, respectively.

The fuel cell vehicle control device 121 controls the inverter 103 according to the driver's request,
In order to generate electric power required for the inverter by the fuel cell 101, the flow rate and pressure of air and hydrogen supplied to the fuel cell 101 are controlled by the compressor 114 and the air regulating valve 13.
3. Control using the pressure adjusting valve 134. Further, the pure water supply pump 113 is controlled in order to control the humidification amount of air and hydrogen supplied to the fuel cell 101. In addition, the cooling water supply pump 1
15 is controlled. Such a fuel cell system is realized by performing various controls as described above in the fuel cell vehicle control device 121. However, if there is an abnormality in this control system, further abnormality, particularly, the fuel cell 101 It is necessary to stop the system so that the function of the system does not deteriorate.

Therefore, for example, in the technique described in Japanese Patent Application Laid-Open No. 7-78624, a differential pressure detector and a differential pressure control valve are newly provided in order to control the differential pressure between the hydrogen electrode and the air electrode of the fuel cell. It has been proposed to prevent the function of the fuel cell from deteriorating by controlling the pressure difference between the two electrodes within an allowable value when the protection is stopped.

[0009]

However, in the above-mentioned prior art, when the fuel cell system is stopped for protection, a new voltage difference is prevented in order to prevent the functional deterioration due to the differential pressure between the hydrogen electrode and the air electrode exceeding an allowable value. Since the pressure control means is provided, there is a problem that the configuration of the system becomes large and the cost is increased.

The present invention has been made in view of the above circumstances, and provides a control device for minimizing deterioration of the function of a fuel cell without adding new parts when the protection of the fuel cell system is stopped. It is intended to do so.

[0011]

In order to achieve the above object, the invention according to claim 1 detects an abnormality in a fuel cell main body and an auxiliary machine that generate power by an electrochemical reaction of a fuel gas and an oxidizing gas and stops protection. A protection stop control device for a fuel cell system to be controlled, comprising: abnormality detection means for detecting an abnormal state of the fuel cell main body and the auxiliary equipment; and a system full stop mode according to information detected by the abnormality detection means. A gas control stop mode, a power generation emergency stop mode, and a stop mode selection unit that selects any one of the stop modes from the power generation normal stop mode, and a stop control unit that stops the fuel cell system according to the selected stop mode. The gist is that it is provided.

According to a second aspect of the present invention, in order to achieve the above object, in the protection stop control device for a fuel cell system according to the first aspect, the abnormality detecting means includes an abnormality in a power supply system of the control device or an abnormality in the control device itself. When an error is detected,
The gist of the invention is that the stop mode selection means selects a system full stop mode for stopping all controls of the fuel cell system.

According to a third aspect of the present invention, in the protection stop control device for a fuel cell system according to the first aspect, the abnormality detecting means includes an abnormality or a gas flow rate relating to gas pressure control of the fuel cell system. When detecting an abnormality related to control, the stop mode selecting means selects a gas control stop mode in which only the power generation control of the fuel cell system and the gas pressure / flow rate control are stopped.

According to a fourth aspect of the present invention, in the protection stop control device for a fuel cell system according to the first aspect, the abnormality detecting means detects an abnormality related to power generation power control of the fuel cell system. The gist of the invention is that the stop mode selecting means selects a power generation emergency stop mode of the fuel cell system for stopping only the power generation control of the fuel cell system.

According to a fifth aspect of the present invention, in the protection stop control device for a fuel cell system according to the first aspect, the abnormality detecting means relates to an abnormality related to cooling control of the fuel cell system or humidification control. When an abnormality is detected, the stop mode selecting means stops only the cooling control or the humidification control of the fuel cell, and selects a power generation normal stop mode in which the power generation control is gently stopped.

According to a sixth aspect of the present invention, there is provided a protection stop control device for a fuel cell system according to the first aspect, wherein the stop control means includes the gas control stop mode, the power generation emergency stop mode, And when the fuel cell is being stopped in any one of the power generation normal stop modes, and when the abnormality detection unit detects an abnormality with a higher degree of urgency than the stop mode, the stop mode selection unit performs the detection. The stop mode is changed to a stop mode corresponding to the abnormality with a high degree of urgency, and the stop control means performs stop control according to the changed stop mode.

[0017]

According to the first aspect of the present invention, the protection stop of the fuel cell system for controlling the protection stop by detecting an abnormality of the fuel cell main body and the auxiliary machine that generates power by the electrochemical reaction of the fuel gas and the oxidizing gas. A control device, an abnormality detecting means for detecting an abnormal state of the fuel cell main body and the auxiliary machine,
Stop mode selecting means for selecting one of the stop modes from the system total stop mode, the gas control stop mode, the power generation emergency stop mode, and the power generation normal stop mode, according to the information detected by the abnormality detection means, A stop control unit for stopping the fuel cell system according to the selected stop mode, which is required for normal control by selecting a stop mode in consideration of a failure mode of the system and performing stop control. It is possible to minimize the deterioration of the function of the fuel cell with only the simple components.

According to the second aspect of the present invention, in addition to the effect of the first aspect, when the abnormality detecting means detects an abnormality in the power supply system of the control device or an abnormality in the control device itself, The stop mode selection means selects the system entire stop mode for stopping all control of the fuel cell system. Therefore, when the loss of the control function of the fuel cell system is detected, the entire system is immediately stopped. Therefore, it is possible to minimize the deterioration of the function of the fuel cell.

According to the third aspect of the present invention, in addition to the effect of the first aspect, when the abnormality detecting means detects an abnormality related to gas pressure control or an abnormality related to gas flow rate control of the fuel cell system. The stop mode selecting means selects the gas control stop mode in which only the power generation control of the fuel cell system and the pressure / flow rate control of the gas are stopped, so that the loss of the gas control function of the fuel cell system is detected. As a result, the functions other than the cooling control function are quickly stopped, so that the function deterioration of the fuel cell can be minimized, including the function deterioration caused by the temperature rise of the fuel cell after the power generation is stopped.

According to the fourth aspect of the present invention, in addition to the effect of the first aspect, when the abnormality detecting means detects an abnormality related to the power generation control of the fuel cell system, the stop mode selecting means. Is configured to select the power generation emergency stop mode of the fuel cell system in which only the power generation control of the fuel cell system is stopped. Therefore, the loss of the power generation control function of the fuel cell system is detected, and at least the gas control function and the cooling control are detected. In order to quickly stop the power generation control function without stopping the function, the fuel function is reduced, including the function deterioration due to the increase in the differential pressure between the two poles of the fuel cell when the fuel cell is stopped and the function deterioration due to the temperature rise of the fuel cell after the power generation is stopped. It becomes possible to minimize the deterioration of the battery function.

According to the fifth aspect of the invention, in addition to the effect of the first aspect, when the abnormality detecting means detects an abnormality related to cooling control or humidification control of the fuel cell system, The stop mode selection means stops only the cooling control or the humidification control of the fuel cell and selects the power generation normal stop mode in which the power generation control is gently stopped. Therefore, the cooling control function or the humidification control function of the fuel cell system is performed. The power generation control function is gently stopped without detecting the loss of the gas control function without stopping the gas control function. It becomes possible.

According to the invention described in claim 6, in addition to the effect of the invention described in claim 1, the stop control means may control the gas control stop mode, the power generation emergency stop mode, and the power generation normal stop mode. While the fuel cell is being stopped in any one of the stop modes, when the abnormality detection unit detects an abnormality with a higher degree of urgency than the stop mode, the stop mode selection unit sets the detected abnormality with a higher degree of urgency. To the stop mode corresponding to, the stop control means, so as to stop control according to the changed stop mode,
If a more urgent abnormality is detected during the stop control by selecting the stop mode according to the abnormality detected first, the stop mode is changed according to the more urgent abnormality and the operation is stopped immediately. There is an effect that can be.

In particular, in a fuel cell system, a certain failure is often detected as a plurality of abnormalities with a time difference, and among the plurality of abnormalities, when the most urgent abnormality is detected first. Not necessarily. It is also conceivable that the first abnormal situation will cause a second abnormal situation. For this reason, unless a fixed stop mode is selected based on the information on the abnormality detected first and it is not possible to adapt to the abnormality detected thereafter, it is difficult to minimize the functional deterioration. However, according to the invention as set forth in claim 6, even if an abnormality with a high degree of urgency is not detected first, the fuel cell system is stopped in accordance with the abnormal state with the highest degree of urgency, so that functional deterioration is effectively avoided. can do.

[0024]

Next, an embodiment of the present invention will be described in detail with reference to the drawings. The fuel cell system to which the protection stop control device according to the present invention is applied is not particularly limited as long as the fuel cell system includes a fuel cell main body that generates power by an electrochemical reaction of a fuel gas and an oxidizing gas, and an auxiliary machine. The description will be made with reference to the conventional example of FIG.

[First Embodiment] FIG. 1 is a block diagram showing the main configuration of a first embodiment of a protection stop control device for a fuel cell system according to the present invention.
21.

In FIG. 1, a protection stop control device 1 includes an abnormality detecting section 2 for detecting an abnormal state of a fuel cell main body and an auxiliary machine.
And a stop mode selecting unit that selects one of a system stop mode, a gas control stop mode, a power generation emergency stop mode, and a power generation normal stop mode according to information detected by the abnormality detection unit 2. 3 and a stop control unit 4 for stopping the fuel cell system according to the selected stop mode.

The abnormality detecting section 2 detects an abnormality of the fuel cell main body and the auxiliary equipment, and detects a power supply system signal of the control device and an abnormality of the control device itself in order to detect an abnormality of the power supply system of the control device. Signal of the control device itself to detect, gas pressure control system signal to detect abnormality related to gas pressure control, gas flow control system signal to detect abnormality related to gas flow control, power generation control of fuel cell system Power generation control system signal and load control system signal to detect abnormality, cooling control system signal to detect abnormality related to cooling control of fuel cell system, and humidification control to detect abnormality related to humidification control of fuel cell system System signals are input.

As the power supply system signal of the control device, for example, there is a power supply determination signal (generally abbreviated as a power accuracy signal) indicating that the power supply voltage supplied to the control device is in a stable state.
The signals of the control device itself include a parity error signal, a stack overflow signal, a program abnormality detection signal indicating that a contradiction in program control has been detected, and the like.

The abnormalities detected from the gas pressure control system signal include abnormalities of the hydrogen pressure sensor 135, abnormalities of the air pressure sensor 132, abnormalities of the compressor 114, abnormalities of the pressure regulating valve 134, abnormalities of the air pressure regulating valve 133, hydrogen Abnormal pressure rise of the pressure sensor 135 or the air pressure sensor 132;
The abnormal pressure drop, the differential pressure abnormality between the hydrogen pressure sensor 135 and the air pressure sensor 132, and the like.

The abnormality detected from the gas flow control system signal is an abnormality of the air mass flow sensor 131.

The abnormalities detected from the power generation control system signal include the abnormal voltage drop of the fuel cell 101 and the inverter 103
Is abnormal.

The abnormality detected from the load control system signal is, for example, an abnormality of the AC motor 104 for driving the vehicle.

The abnormalities detected from the cooling control system signal include abnormalities of the cooling water supply pump 115, abnormalities of the cooling water temperature sensor 136, abnormalities of the radiator 116, and the like.

An abnormality detected from the humidification control system signal includes an abnormality of the pure water supply pump 113 and the like.

The stop mode selection unit 3 selects one of the stop modes of the system total stop mode, the gas control stop mode, the power generation emergency stop mode, and the power generation normal stop mode according to the abnormal state detected by the abnormality detection unit 2. Then, the stop mode is notified to the stop control unit 4.

The correspondence between the abnormal state detected by the abnormality detecting section 2 and the stop mode selected by the stop mode selecting section 3 is as follows.

When an abnormality of the power supply system of the control device is detected from the power supply system signal of the control device, and when an abnormality of the control device itself is detected from the abnormality detection signal of the control device itself, all control of the fuel cell system is performed. Select the system all stop mode to stop.

When an abnormality relating to gas pressure control is detected from the gas pressure control system signal, and when an abnormality relating to gas flow control is detected from the gas flow control system signal, the power generation control of the fuel cell system and the gas pressure / flow rate are performed. A gas control stop mode in which only control is stopped is selected.

When an abnormality relating to the power generation control of the fuel cell system is detected from the power generation control system signal, and when a load abnormality is detected from the load control system signal, only the power generation control of the fuel cell system is stopped. Select the stop mode.

When an abnormality relating to the cooling control of the fuel cell system is detected from the cooling control system signal, and when an abnormality relating to the humidification control of the fuel cell system is detected from the humidification control system signal, the cooling control or the humidification of the fuel cell system is performed. A power generation normal stop mode in which only control is stopped and power generation control is gently stopped is selected.

The stop control unit 4 stops the fuel cell system according to the stop mode selected by the stop mode selection unit 3. In the system all stop mode, all controls of the fuel cell system are stopped. In the gas control stop mode, only the power generation control of the fuel cell system and the gas pressure / flow rate control are stopped. In the case of the power generation emergency stop mode, only the power generation control of the fuel cell system is stopped. In the case of the power generation normal stop mode, only the cooling control or the humidification control of the fuel cell system is stopped, and the power generation control is gently stopped.

Next, the processing operation of the first embodiment will be described with reference to the schematic flowchart of FIG.

In step S201, various diagnoses are made for the fuel cell body and the auxiliary equipment, and an abnormal signal is detected. In step S202, a stop mode is selected and branched based on the failure information detected in step S201. For example, when the abnormality of the fuel cell vehicle control device 121 itself or the abnormality of the power supply system of the fuel cell system is detected in step S201, the system entire stop mode is selected, and the process branches to step S203. Is detected, a gas control stop mode is selected and the process branches to step S204. If a power generation control abnormality is detected in step S201, a power generation emergency stop mode is selected and the process branches to step S206, and cooling is performed in step S201. If a control abnormality is detected, the normal power generation stop mode is selected and the process branches to step S208. If a humidification control abnormality is detected in step S201, the normal power generation stop mode is selected and the process branches to step S210.

In step S203, all of gas control, power generation control, cooling control, and humidification control are stopped. This is to prevent a new system from degrading due to the loss of function of the entire control system (such as a degrading of the entire system that is more serious than the degradation of the fuel cell membrane).

In step S204, the gas control is stopped. This is to prevent a new system from deteriorating due to the loss of the gas control function. Further, since the gas control is stopped, normal power generation from the fuel cell 101 cannot be performed, and the power generation function is also stopped. Further, since the power generation control is stopped, the humidification control is not required, so the humidification control is also stopped. During that time, the cooling control does not stop. This is to prevent the temperature of the fuel cell 101 from rising after the power generation is stopped, thereby preventing the fuel cell 101 from being damaged.

Here, the gas control is stopped, for example, by stopping the compressor 114, fully opening the air pressure regulating valve 133, fully closing the pressure regulating valve 134, and controlling the flow rates of air and hydrogen supplied to the fuel cell 101. Zero and
These pressures are set to approximately atmospheric pressure. As a result, when the gas control function is lost, the pressure difference between the hydrogen electrode and the air electrode may not be controlled within a predetermined value. This can minimize the deterioration of the function of the fuel cell (protect the membrane). Stopping the power generation control means, for example, stopping the operation of the inverter 103 and setting the power generation amount of the fuel cell 101 to zero.

Stopping the cooling control means, for example, stopping the operation of the cooling water supply pump 115 to reduce the amount of cooling water supplied to the fuel cell 101 to zero. Stopping the humidification control means, for example, stopping the driving of the pure water supply pump 113 to reduce the amount of pure water supplied to the humidifier 111 to zero.

In step S205, the cooling control is stopped after a lapse of a predetermined time, that is, after there is no longer a possibility that the temperature of the fuel cell 101 will rise. In step S206, the power generation control is stopped. This is to prevent functional deterioration of the new system due to the loss of the power generation control function. In addition, since the power generation control is stopped, the humidification control is not required, so the humidification control is also stopped. Meanwhile, the gas control and the cooling control are not stopped. This is to prevent the function of the fuel cell 101 from deteriorating by controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 within a predetermined value by performing gas control after stopping power generation. , Fuel cell 1
This is to prevent the function of the fuel cell 101 from deteriorating due to a rise in the temperature of the fuel cell 101.

In step S207, the gas control is stopped while controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 within a predetermined value. After a predetermined time has elapsed, that is, there is a possibility that the temperature of the fuel cell 101 may rise. After that, the cooling control is stopped.

In step S208, the cooling control is stopped. This is to prevent a new decrease in system function due to the loss of the cooling control function. During this time, the gas control and the power generation control are not stopped. This is to prevent the function of the fuel cell 101 from deteriorating by performing gas control and stopping while controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 within a predetermined value. This is to suppress the phenomenon that the gas pressure suddenly increases when the gas consumed in the power generation is suddenly stopped when the gas is stopped. Naturally, the time required for the gentle stop is a time in consideration of the fact that the function of the fuel cell 101 does not immediately deteriorate even if the cooling control is stopped.

In step S209, the gas control is stopped while controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 within a predetermined value. Stop in no time.

In step S210, the humidification control is stopped. This is to prevent a new decrease in system function due to the loss of the humidification control function. During this time, the gas control and the power generation control are not stopped. This is to prevent the function of the fuel cell 101 from deteriorating by controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 to be within a predetermined value by performing gas control. This is to suppress the phenomenon that the gas pressure suddenly increases when the gas consumed in the power generation is suddenly stopped when the gas is stopped. Naturally, the time required for the gentle stop is a time considering that the function of the fuel cell 101 does not immediately deteriorate even if the humidification control is stopped.

In step S 211, the gas control is stopped while controlling the pressure difference between the hydrogen electrode and the air electrode of the fuel cell 101 within a predetermined value, and the power generation also stops when the gas pressure at both electrodes of the fuel cell 101 sharply increases. Stop in no time.

According to the above control, depending on the abnormal state of the fuel cell system, priority can be given to the protection of the membrane of the fuel cell, and the abnormal stop processing can be performed with the deterioration of the membrane function being minimized.

[Second Embodiment] Next, a second embodiment of the protection stop control apparatus for a fuel cell system according to the present invention will be described with reference to the flowcharts of FIGS. The configuration of the protection stop control device of the second embodiment is the same as that of the first embodiment shown in FIG. 1, and the fuel cell system to which this embodiment is applied is the same as that of the first embodiment.
The details of each stop in the system total stop mode, the gas control stop mode, and the power generation emergency stop mode are the same as those in the first embodiment. However, the power generation normal stop mode is divided into a cooling stop mode and a humidification stop mode. is there.

The second embodiment is different from the first embodiment in that the stop control unit 4 controls the fuel cell in any one of the gas control stop mode, the power generation emergency stop mode, the cooling stop mode, and the humidification stop mode. When the abnormality detection unit 2 detects an abnormality with a higher degree of urgency than the stop mode, the stop mode selection unit 3 changes to a stop mode corresponding to the detected abnormality with a higher degree of urgency. The stop control unit 4 performs stop control according to the changed stop mode.

In other words, the stop mode selector 3 selects the first stop mode based on the information on the abnormal state detected first by the abnormality detector 2, and the stop controller 4 stops according to the first stop mode. If the abnormality detection unit 2 detects a second abnormal state having a higher degree of urgency during control, the stop mode selection unit 3 changes the stop mode selection based on the second abnormal state. Means performing stop control in accordance with the changed stop mode. For this reason, the flowcharts of FIGS. 3 to 5 are configured as subroutines that are called and executed at regular intervals.

In the following description, the degree of urgency is determined in the order of system total stop mode> gas control stop mode> power generation emergency stop mode> cooling stop mode and humidification stop mode.
When a plurality of stop modes are set, stop processing is performed according to the stop mode with the highest urgency.

In FIG. 3, first, in step S301, various diagnoses are made on the fuel cell main body and the auxiliary equipment, and an abnormal signal is detected. In step S302, it is determined whether there is an abnormality. If there is no abnormality, return without doing anything. If an abnormality is detected, it is determined in step S303 whether or not the power supply system of the control device is abnormal. If the power supply system is abnormal, the process proceeds to step S305. If the power system is not abnormal, it is determined in step S304 whether or not the control device itself is abnormal. If the control device itself is abnormal, step S30
Move to 5.

At step S305, the system sets the most urgent system all stop mode flag irrespective of the presence or absence of the selected stop mode, and then at step S306, stops gas control, power generation control, and cooling control. Then, the humidification control is stopped, and the process returns.

If it is determined in step S304 that the control device itself is not abnormal, it is determined in step S307 whether the gas control stop mode flag is set.

If the gas control stop mode flag is set in the determination in step S307, the stop processing in the gas control stop mode is in progress, and it is determined in step S314 whether a predetermined time has elapsed based on the presence or absence of the timer run-out. If nothing is running out, return without doing anything. If the timer has run out in step S314, the cooling control is stopped in step S315, and the process returns.

If it is determined in step S307 that the gas control stop mode flag is not set, it is determined in step S30 whether or not there is a new gas supply system abnormality.
In step S30, it is determined whether there is an abnormality in the gas pressure control.
At 9 it is determined whether there is an abnormality in the gas flow control.

If there is an abnormality in the gas pressure control in step S308 or if there is an abnormality in the gas flow rate control in step S309, the process proceeds to step S310, in which a gas control stop mode flag is set. The power generation control and the humidification control are stopped.
In step S312, a timer is started to measure the time until the cooling is stopped, and the process returns.

If there is no abnormality in the gas control system in both steps S308 and S309, it is determined in step S316 whether or not the power generation emergency stop mode flag is set.

If the power generation emergency stop mode flag is set in the determination at step S316, the stop processing in the power generation emergency stop mode is in progress, and the gas control is gently stopped at step S341.
In step S342, it is determined whether or not a predetermined time has elapsed based on the presence or absence of a timer run-out. If the timer has not run out, the process returns without doing anything. Step S3
If the timer is running out at 42, step S3
At 43, the cooling control is stopped, and the process returns.

If it is determined in step S316 that the emergency power generation stop mode flag has not been set, step S31 is executed.
It is determined in step 7 whether or not the power generation control is abnormal. If the power generation control is abnormal, the process proceeds to step S322. If the power generation control is not abnormal, it is determined in step S318 whether the load is abnormal.
If the load is abnormal, the process moves to step S322.

In step S322, the power generation emergency stop mode flag is set, and then in step S323, the power generation control and the humidification control are stopped. And step S32
In step S4, a timer is started to measure the time until the cooling is stopped, and in step S325, the gas control is gently stopped.

If there is no abnormality in the load in step S318, it is determined in step S319 whether the humidification control stop mode flag or the cooling control stop mode flag is set, and if set, the process proceeds to step S344.

If both the humidification control stop mode flag and the cooling control stop mode flag are not set in step S319, it is determined in step S326 whether or not the cooling control is abnormal.
At 327, it is determined whether or not the humidification control is abnormal. If the humidification control is abnormal, the process proceeds to step S328.

In step S328, the humidification control stop mode flag is set, and then in step S329, the humidification control is stopped. Then, in step S330, a timer is started to measure the time until the complete stop, and in step S331, the power generation control and the gas control are gently stopped. .

If it is determined in step S326 that the cooling control is abnormal, the cooling control stop mode flag is set in step S332, the cooling control is stopped in step S333, and the process proceeds to step S330.

In step S344, it is determined whether the cooling control stop mode flag has been set. If the cooling stop mode flag is set, the power generation control and gas control are gently stopped in step S345 because the cooling process is being stopped in the cooling control stop mode. It is determined whether or not a predetermined time has elapsed based on the presence or absence of a timer run-out. If the timer has not run out, the process returns without doing anything. If the timer has run out in step S346, the humidification control is stopped in step S347, and the routine returns.

If the cooling control stop mode flag is not set in step S344, step S34
At 8, it is determined whether or not the humidification control stop mode flag is set. If the humidification control stop mode flag is set in the determination in step S348, the stop processing in the humidification control stop mode is in progress, and the power generation control and gas control are gently stopped in step S349. After a slight decrease, it is determined in step S350 whether or not a predetermined time has elapsed based on whether or not the timer has run out. If the timer has not run out, the process returns without doing anything. If the timer has run out in step S350, the cooling control is stopped in step S351, and the process returns.

As described above, according to the second embodiment of the present invention, during the stop processing in the first stop mode based on the information of the abnormal state detected first, a new abnormality having a higher urgency is performed. When a state is detected, the stop mode is selected and changed based on the information on the new abnormal state, and the stop control is performed according to the changed stop mode. Also shuts down the fuel cell system in response to the most urgent abnormal condition,
Functional degradation can be effectively avoided.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing a configuration of a protection stop control device for a fuel cell system according to the present invention.

FIG. 2 is a flowchart illustrating a control operation of the fuel cell system according to the first embodiment.

FIG. 3 is a flowchart illustrating a control operation of a fuel cell system according to a second embodiment.

FIG. 4 is a flowchart illustrating a control operation of the fuel cell system according to the second embodiment.

FIG. 5 is a flowchart illustrating a control operation of the fuel cell system according to the second embodiment.

FIG. 6 is a schematic configuration diagram showing a configuration of a conventional fuel cell system.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 protection stop control device 2 abnormality detection unit 3 stop mode selection unit 4 stop control unit 101 fuel cell main unit 103 inverter 104 vehicle driving AC motor 111 humidifier 112 high-pressure hydrogen cylinder 113 pure water supply pump 114 compressor 115 cooling water supply pump 121 Vehicle control device 131 Air mass flow sensor 132 Air pressure sensor 133 Air pressure regulating valve 134 Pressure regulating valve 135 Hydrogen pressure sensor 136 Cooling water temperature sensor

 ──────────────────────────────────────────────────続 き Continued on front page F term (reference) 3D035 AA00 AA03 AA04 5H027 AA02 DD00 KK01 KK21 KK28 KK52 5H115 PA00 PA08 PC06 PG04 PI18 PU08 PV09 QI00 QN10 SE06 TI10

Claims (6)

[Claims] 1. A protection stop control device for a fuel cell system, which detects an abnormality in a fuel cell main body that generates power by an electrochemical reaction between a fuel gas and an oxidizing gas and an auxiliary machine and controls a protection stop, wherein the fuel cell main body is provided. Abnormality detecting means for detecting an abnormal state of the auxiliary equipment, and, based on information detected by the abnormality detecting means, from among a system total stop mode, a gas control stop mode, a power generation emergency stop mode, and a power generation normal stop mode. A protection stop control device for a fuel cell system, comprising: stop mode selection means for selecting one of the stop modes; and stop control means for stopping the fuel cell system according to the selected stop mode. 2. The system according to claim 2, wherein when the abnormality detection unit detects an abnormality in the power supply system of the control unit or an abnormality in the control unit itself, the stop mode selection unit stops all control of the fuel cell system. 2. The protection stop control device for a fuel cell system according to claim 1, wherein a mode is selected. 3. The stop mode selecting means, when the abnormality detecting means detects an abnormality relating to gas pressure control or an abnormality relating to gas flow rate control of the fuel cell system, the stop mode selecting means comprises: 2. The protection stop control device for a fuel cell system according to claim 1, wherein a gas control stop mode for stopping only flow control is selected. 4. When the abnormality detecting means detects an abnormality related to the power generation control of the fuel cell system, the stop mode selection means stops the power generation control of the fuel cell system only. 2. The protection stop control device for a fuel cell system according to claim 1, wherein a mode is selected. 5. The stop mode selecting means stops only the cooling control or the humidification control of the fuel cell, when the abnormality detection means detects an abnormality related to the cooling control of the fuel cell system or an abnormality related to the humidification control, 2. The protection stop control device for a fuel cell system according to claim 1, wherein a power generation normal stop mode for gently stopping the power generation control is selected. 6. The abnormality detection means when the stop control means is stopping the fuel cell in one of the gas control stop mode, the power generation emergency stop mode, and the power generation normal stop mode. When detecting an abnormality with a higher urgency than the stop mode, the stop mode selecting means changes to a stop mode corresponding to the detected abnormality with a high urgency, and the stop control means changes the stop mode after the change. 3. The protection stop control device for a fuel cell system according to claim 1, wherein the stop control is performed according to the following.