JP2009043545A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system capable of restraining generation of damages, accompanying regeneration treatment, concerning the system equipped with an energy-regenerating mechanism. <P>SOLUTION: The fuel cell system is provided with a fuel cell 10, an oxidizing gas piping 18 for supplying oxidizing gas to a cathode, a compressor 20 arranged at the oxidizing gas piping 18, a compressor motor 34 coupled with a driving shaft of the compressor 20 and functioning as a motor, as well as, a power generator, a regenerating means for regenerating electric energy by driving the compressor motor 34, by rotating force of the compressor 20, when the supply volume of the oxidizing gas is reduced, an allowable power setting means setting allowable power of auxiliary units of the fuel cell 10; and a control means controlling regeneration power by the regenerating means so that the power input into the auxiliary units is to become the allowable power. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fuel cell system, and more particularly to a fuel cell system provided with an energy regeneration mechanism.

  The fuel cell is used as a fuel cell stack (hereinafter referred to as “FC stack”) in which a plurality of fuel cell cells (hereinafter referred to as “unit cells”) are stacked. The unit cell itself is a laminate of planar members, and has a membrane electrode assembly (MEA) formed by sandwiching an electrolyte membrane between electrodes from both sides, and the MEA is separated from both sides by a separator. It is comprised by pinching. Then, an anode gas containing hydrogen is supplied to the anode, and a cathode gas containing oxygen such as air is supplied to the cathode, so that an electrochemical reaction occurs in both electrodes and a voltage is generated between both electrodes. ing.

  In a system including such a fuel cell, various energy regeneration methods have been proposed as methods for improving the energy efficiency of the entire system. For example, Japanese Patent Application Laid-Open No. 2006-333543 discloses a fuel cell system that performs regenerative processing when the rotational speed of a pump is reduced. More specifically, according to this system, the hydrogen circulation flow path is provided with the hydrogen circulation pump, and the regeneration process is performed when the pump rotation speed is reduced. Thereby, the energy efficiency of the system can be improved.

JP 2006-333543 A JP 2005-83318 A JP 2004-185820 A

  However, in the conventional system described above, when controlling the electric power regenerated by the regenerative processing, the allowable power of various auxiliary devices constituting the fuel cell system is not taken into consideration. For this reason, depending on the magnitude of the regenerated electric power, it is assumed that the allowable electric power of the auxiliary devices will be exceeded. In such a case, there is a possibility that the components of the system may be damaged.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a fuel cell system that can suppress the occurrence of damage to the fuel cell system that accompanies regenerative processing.

In order to achieve the above object, a first invention is a fuel cell system,
A fuel cell that receives a supply of fuel gas containing hydrogen at the anode and a power supply that receives supply of an oxidizing gas containing oxygen at the cathode; and
A reaction gas flow path for supplying a reaction gas to the fuel cell;
A compressor disposed in the reaction gas flow path;
A rotating electrical machine that is connected to the drive shaft of the compressor and functions as a prime mover and a generator;
Regenerative means for regenerating electrical energy by driving the rotating electrical machine by the rotational force of the compressor when reducing the supply amount of the reactive gas;
An allowable power setting means for setting an allowable power of the fuel cell auxiliary devices;
Control means for controlling the regenerative power by the regenerative means so that the power input to the auxiliary devices is less than or equal to the allowable power;
It is characterized by providing.

The second invention is the first invention, wherein
The auxiliary devices include a converter interposed between the fuel cell and a power storage device for storing electric power,
The control means controls the regenerative power by the regenerative means so that the difference between the total power generated and regenerated in the fuel cell system and the power consumed in the fuel cell system is equal to or less than the allowable power. It is characterized by that.

The third invention is the first or second invention, wherein
The auxiliary devices include a power storage device for storing electric power,
The battery further comprises power storage availability determination means for determining whether power can be stored in the power storage device,
The allowable power setting means sets the allowable power of the power storage device to zero when it is determined that the power storage device cannot store power.

In addition, a fourth invention is any one of the first to third inventions,
It further comprises an abnormality detection means for detecting an abnormality of the auxiliary devices,
The allowable power setting means sets the allowable power of the auxiliary device in which an abnormality has been detected by the abnormality detection means to be lower than that in a normal state.

Further, a fifth aspect of the present invention is any one of the first to third aspects of the invention,
It further comprises an abnormality detection means for detecting an abnormality of the auxiliary devices,
The control means prohibits the regenerative operation by the regenerative means when the abnormality is detected.

The sixth invention is the fourth or fifth invention, wherein
The auxiliary devices include a power storage device for storing electric power,
The abnormality detection means detects an abnormality of the power storage device.

The seventh invention is the fourth or fifth invention, wherein
The auxiliary devices include a converter interposed between the fuel cell and a power storage device for storing electric power,
The abnormality detecting means detects an abnormality of the converter.

The eighth invention is the fourth or fifth invention, wherein
The auxiliary devices include an inverter interposed between the fuel cell and the rotating electrical machine,
The abnormality detecting means detects an abnormality of the inverter.

The ninth invention is the fourth or fifth invention, wherein
The abnormality detecting means detects a power supply cutoff abnormality of the fuel cell system.

  According to the first invention, the regenerative power is controlled so that the power input to the auxiliary devices of the fuel cell does not exceed the allowable power of the auxiliary devices. Damage to equipment and the like can be effectively suppressed.

  The power generated by the fuel cell and the power regenerated by the compressor are transformed through the converter and then stored in the power storage device. According to the second aspect of the invention, the difference between the sum of the power generated and regenerated in the fuel cell system and the power consumed in the fuel cell system is the tolerance of the converter interposed between the fuel cell and the power storage device. The regenerative power is controlled so as to be equal to or lower than the power. For this reason, according to this invention, the situation where a converter is damaged can be suppressed effectively.

  The power generated by the fuel cell and the power regenerated by the compressor are stored in the power storage device. According to the third invention, when it is determined that the power storage device is in a state where it cannot store power, a range in which the power storage device does not store power, that is, the allowable power of the power storage device is set to zero. For this reason, according to this invention, the situation where an electrical storage apparatus is damaged by overcharge can be suppressed effectively.

  According to the fourth invention, when an abnormality of the fuel cell system is detected, the allowable power of the auxiliary device in which the abnormality is detected is set lower than that in the normal time. For this reason, according to this invention, the situation where the damage of the auxiliary device in which abnormality has generate | occur | produced can be suppressed effectively.

  According to the fifth aspect of the present invention, the regeneration operation by the compressor is prohibited when an abnormality of the auxiliary devices is detected. For this reason, according to this invention, the situation where the abnormality of auxiliary devices expands can be suppressed effectively.

  According to the sixth invention, the abnormality of the converter can be detected as the abnormality detection means.

  According to the seventh invention, the abnormality of the power storage device can be detected as the abnormality detection means.

  According to the eighth aspect, the abnormality of the compressor inverter can be detected as the abnormality detection means.

  According to the ninth aspect of the present invention, an abnormality due to power-off of the fuel cell system can be detected as the abnormality detection means.

  Several embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the element which is common in each figure, and the overlapping description is abbreviate | omitted. The present invention is not limited to the following embodiments.

Embodiment 1 FIG.
[Configuration of Embodiment 1]
FIG. 1 is a diagram for explaining a system configuration according to the first embodiment of the present invention. As shown in FIG. 1, the system according to the present embodiment is a system applied to a fuel cell vehicle equipped with a fuel cell stack (FC stack) 10. The FC stack 10 is configured by stacking a plurality of fuel cells. Each fuel cell is configured such that a proton conductive electrolyte membrane (not shown) is sandwiched between an anode and a cathode, and both sides are sandwiched between conductive separators.

  A hydrogen gas pipe 12 for supplying hydrogen gas as a fuel gas to the anode is connected to the FC stack 10. The upstream end of the hydrogen gas pipe 12 is connected to a hydrogen gas supply source (high pressure hydrogen tank, reformer, etc.) 14, and a pressure regulating valve 16 is disposed downstream thereof. The hydrogen gas is depressurized by the pressure regulating valve 16, depressurized to a desired pressure, and then supplied to the FC stack 10. The hydrogen gas that has passed through the fuel cell stack 10 is exhausted to a hydrogen off-gas pipe (not shown). A diluter (not shown) is connected downstream of the hydrogen offgas pipe. The hydrogen gas remaining in the hydrogen off-gas is discharged to the outside after being diluted to a sufficiently low concentration in the diluter.

  The FC stack 10 is connected to an oxidizing gas pipe 18 for supplying air as an oxidizing gas to the cathode. The upstream end of the oxidizing gas pipe 18 is open to the atmosphere, and the compressor 20 is disposed downstream thereof. Air sucked by the operation of the compressor 20 passes through the oxidizing gas pipe 18 and is supplied to the FC stack 10. In the FC stack 10, a power generation reaction is performed by receiving the supply of these hydrogen gas and oxidizing gas.

  The output terminal of the FC stack 10 is connected to the power storage device 24 via the DC-DC converter 22. The DC-DC converter 22 is a device for converting the electric power generated in the FC stack 10 into a voltage suitable for the power storage device 24. The power storage device 24 is a power storage device that plays a role of complementing the FC stack 10 as a power source of the fuel cell vehicle. In addition, a voltmeter 52 is disposed in the power storage device 24.

  The fuel cell vehicle shown in FIG. 1 includes a traction motor 26. The traction motor 26 is a motor generator having both a function of driving the fuel cell vehicle as a prime mover and a function of generating electric power as a generator. The rotation shaft of the traction motor 26 is connected to a drive shaft 28 of the vehicle. The drive shaft 28 is connected to wheels 30 via a differential gear (not shown). According to such a configuration, the power output from the traction motor 26 is transmitted to the road surface via the drive shaft 28 and the wheels 30.

  The input / output terminal of the traction motor 26 is connected to the traction motor inverter 32. Further, the traction motor inverter 32 is connected to the FC stack 10 and the power storage device 24 in parallel. The traction motor inverter 32 controls the electric power supplied to the traction motor 26. Specifically, when power is generated in the traction motor 26, the power supplied from the FC stack 10 or the power storage device 24 is converted into AC power suitable for driving the traction motor 26 and supplied to the traction motor 26. Further, at the time of power generation in the traction motor 26, the generated power is supplied and the power is converted into direct current power to be stored in the power storage device 24.

  The drive shaft of the compressor 20 described above is connected to the rotation shaft of the compressor motor 34. The compressor motor 34 is a motor generator having both a function of driving the compressor 20 as a prime mover and a function of generating electric power as a generator using the inertial force of the compressor 20. The input / output terminal of the compressor motor 34 is connected to the compressor inverter 36. Furthermore, the compressor inverter 36 is connected to the FC stack 10 and the power storage device 24 in parallel. The compressor inverter 36 controls electric power supplied to the compressor motor 34. Specifically, when power is generated in the compressor motor 34, the power supplied from the FC stack 10 or the power storage device 24 is converted into AC power suitable for driving the compressor motor 34 and supplied to the compressor motor 34. In addition, when the compressor motor 34 generates power, the generated power is supplied, and the power is converted into DC power to be stored in the power storage device 24.

  The system according to the present embodiment includes an ECU (Electronic Control Unit) 50. Overall control of the fuel cell vehicle is performed by the ECU 50. In addition to the traction motor inverter 32 and the compressor inverter 34 described above, various devices (not shown) are connected to the output unit of the ECU 50. Various sensors such as a voltmeter 52, a vehicle speed sensor 54, and an accelerator opening sensor 56 are connected to the input unit of the ECU 50. The remaining battery level SOC (%) and the vehicle speed SPD (m / s) input from these sensors 52, 54, and 56 are both used as information related to control of the fuel cell vehicle. The ECU 50 drives each device in accordance with a predetermined program based on various types of input information.

[Operation in Embodiment 1]
Next, the operation of the first embodiment will be described. The vehicle according to the present embodiment is a vehicle on which the fuel cell stack 10 is mounted. The FC stack 10 generates electric power according to a required load by reacting hydrogen gas supplied as a fuel gas with air supplied as an oxidizing gas. The generated electric power is supplied to the traction motor 26 via the traction motor inverter 32. The rotational force generated by the traction motor 26 is transmitted to the wheels 30 via the drive shaft 28 and the like, thereby obtaining a propulsive force of the vehicle.

  In addition, the vehicle according to the present embodiment includes a regenerative braking system. Specifically, when a deceleration request for the vehicle is issued, such as when the vehicle is depressed, a part of the kinetic energy of the vehicle is converted into electric energy by the traction motor 26. Thereby, electric energy can be regenerated while functioning as a brake for reducing the speed of the vehicle.

(Regenerative operation by compressor)
The vehicle according to the present embodiment includes a regeneration system that uses the inertial force of the compressor 20. Specifically, a part of the kinetic energy of the compressor 20 is converted into electric energy by the compressor motor 34 when a request for reducing the amount of oxidizing gas is made, such as when a low power generation request is made to the FC stack 10.

  FIG. 2 is a diagram illustrating a change in the rotation speed when the deceleration process of the compressor 20 is executed. As shown by the dotted line in this figure, when the rotational speed is reduced without performing any regeneration processing, the rotational speed is not easily lowered by the action of the inertial force of the compressor 20, but is reduced to the desired rotational speed. It will take a long time. For this reason, even if the power generation amount of the FC stack 10 is reduced, excessive air is supplied into the FC stack 10, and the inside of the FC stack may be dried to reduce the power generation efficiency. In particular, when the compressor 20 is a turbo compressor, unlike a positive displacement compressor such as a Roots compressor, there is no internal compression, so it is more difficult to quickly reduce the rotational speed.

  Therefore, in the present embodiment, regeneration processing by the compressor 20 is executed. As shown by the solid line in FIG. 2, when the regeneration process is executed, the period until the rotation speed is reduced to a desired rotational speed can be effectively shortened as compared with the case where the regeneration process is not executed. Thereby, the deceleration response of the compressor 20 can be improved, and the electrical energy can be regenerated effectively. Hereinafter, the regeneration process by the compressor 20 is referred to as “compressor regeneration”.

(Characteristic operation of the first embodiment)
Examples of the electric power generated by the system in the fuel cell vehicle according to the present embodiment include the electric power generated by the FC stack 10 and the electric power generated by the traction motor 26, as well as the electric power generated by the compressor. Hereinafter, the power configured as the sum of these is referred to as “total generated power”. The total generated power is consumed by driving the traction motor 26 and the compressor motor 34. Hereinafter, the power obtained by subtracting the power consumption of these auxiliary devices from the total generated power is referred to as “total power”. The total power is stored in the power storage device 24 after being converted into a predetermined voltage value in the DC-DC converter 22. The ECU 50 collectively controls these electric powers in order to drive the fuel cell vehicle smoothly.

  Specifically, when the compressor regeneration is executed, the total electric power is increased correspondingly as compared with the case where the compressor regeneration is not executed. For this reason, when the compressor regenerative power is large, power exceeding the input rated value of the converter is input to the DC-DC converter 22, which may cause a failure or the like in the DC-DC converter 22. Further, when the regenerative compressor is performed when the power storage device 24 is fully charged and the total generated power becomes larger than the power consumption, the power storage operation to the power storage device 24 is performed, and the power storage device 24 caused by overcharging Failure may occur.

  Therefore, in the present embodiment, the allowable regeneration power due to compressor regeneration is set in relation to the allowable power of the system auxiliary equipment. Specifically, the allowable power for compressor regeneration is determined so that the total power does not exceed the allowable power of the DC-DC converter 22. Thereby, the situation where the DC-DC converter 22 fails can be suppressed effectively.

  Further, when the power storage device 24 is fully charged, the allowable power for compressor regeneration is determined so that the power storage operation to the power storage device 24 is not executed. Specifically, when the remaining battery SOC of the power storage device 24 is equal to or greater than a predetermined value, the allowable power for compressor regeneration is determined so that the total power becomes zero or less. Thereby, the situation where the power storage device 24 breaks down due to overcharging or the like can be effectively suppressed.

[Specific Processing in Embodiment 1]
Next, with reference to FIG. 3, the specific content of the process performed in this Embodiment is demonstrated. FIG. 3 is a flowchart of a routine in which the ECU 50 executes the compressor regeneration process.

  In the routine shown in FIG. 3, first, the required power generation amount of the FC stack is calculated (step 100). Specifically, the amount of power generated by the FC stack 10 is calculated based on the detection signal from the vehicle speed sensor 54, the detection signal from the accelerator opening sensor 56, and the like. Next, the target rotational speed of the compressor 20 is calculated (step 102). Specifically, the required air amount for realizing the power generation amount of the FC stack 10 calculated in step 100 is calculated, and the target rotational speed of the compressor 20 for realizing the air amount is calculated. Is done.

  Next, it is determined whether or not the rotational speed of the compressor 20 is decelerated (step 104). Specifically, it is determined whether or not the target rotational speed of the compressor 20 specified in step 102 is reduced as compared with the current rotational speed. As a result, when it is determined that the target rotation speed does not become a deceleration, it is determined that the regenerative processing by the compressor cannot be executed, the process proceeds to the next step, and the target rotation calculated by calculating the rotation speed of the compressor 20 Processing to increase the speed is executed, and this routine is terminated (step 106).

  On the other hand, if it is determined in step 104 that the target rotational speed of the compressor 20 is to be decelerated, it is determined that the regenerative processing of the compressor can be executed, the process proceeds to the next step, and the consumption of the traction motor 26 is first performed. Electric power or regenerative electric power is calculated (step 108). Next, the remaining battery SOC of the power storage device 24 is detected based on the detection signal of the voltmeter 52 (step 110).

  Next, the allowable amount of regenerative power by the compressor 20 is calculated (step 112). Specifically, based on the generated power of the FC stack 10 calculated in step 100 and the power consumption or regenerative power of the traction motor 26 calculated in step 108, the total power of the system is DC−. The allowable amount of regenerative power by the compressor is calculated so as not to exceed the input allowable power value of the DC converter 22.

  In step 112, when the battery SOC detected in step 110 is larger than a predetermined threshold for determining full charge, it is determined that the power storage operation to the power storage device 24 cannot be performed. Then, the allowable amount of regenerative power by the compressor is calculated so that the total power of the system becomes zero or less.

  Next, the regeneration process of the compressor 20 is executed (step 114). Here, specifically, when the rotational speed of the compressor 20 is reduced to the target rotational speed calculated in step 102, the compressor motor 34 is within a range not exceeding the allowable amount of regenerative power calculated in step 112. Is regenerated and power is regenerated.

  As described above, according to the system of the present embodiment, when the rotational speed of the compressor 20 is decelerated to the target rotational speed based on the request for reducing the amount of oxidizing gas supplied to the FC stack 10, the DC-DC converter The allowable power for regenerating the compressor is set within a range in which 22 and the power storage device 24 do not fail. Thereby, the situation where the auxiliary equipment of a system fails can be suppressed effectively.

  Further, according to the system of the present embodiment, the rotation speed of the compressor 20 can be reduced by the regeneration process, so that it can be quickly reduced to a desired rotation speed.

  By the way, in the first embodiment described above, the allowable power for compressor regeneration is set so that the input power to the DC-DC converter 22 and the power storage device 24 does not exceed a predetermined amount. The device is not limited to this. That is, the allowable power for compressor regeneration may be set so that the input power does not exceed the allowable value for the inverter and other auxiliary devices.

  In Embodiment 1 described above, when the detected battery SOC is larger than a predetermined threshold for determining full charge, it is determined that the power storage operation to power storage device 24 cannot be performed. However, the method for determining whether or not the power storage device 24 can be charged is not limited to this. That is, the temperature of the power storage device 24 may be detected, and power storage in the power storage device 24 may be limited when the temperature is higher than a predetermined threshold.

  In the first embodiment described above, the oxidizing gas supply compressor 20 disposed in the oxidizing gas pipe 18 is used to regenerate power when a reduction in the amount of oxidizing gas is requested, but this is used for power regeneration. The compressor to be used is not limited to this. That is, in a system including a hydrogen circulation pipe for circulating hydrogen off-gas in the FC stack 10 again and a hydrogen circulation compressor arranged in the hydrogen circulation pipe, the hydrogen circulation compressor is used to generate hydrogen. It is good also as regenerating electric power at the time of the reduction request | requirement of the circulation amount.

  In the first embodiment described above, the FC stack 10 is the “fuel cell” in the first invention, the oxidant gas pipe 18 is the “reactive gas flow path” in the first invention, and the compressor motor 34 is This corresponds to the “rotary electric machine” in the first invention. Further, when the ECU 50 executes the process of step 112, the “allowable power setting means” in the first invention executes the process of step 114, so that the “regeneration means in the first invention”. "And" control means "are realized, respectively.

  In the first embodiment described above, the DC-DC converter 22 corresponds to the “converter” in the second aspect of the invention, and the ECU 50 executes the process of step 112, whereby the second step. The “allowable power setting means” in the present invention is realized.

  In the first embodiment described above, power storage device 24 corresponds to the “power storage device” in the third aspect of the invention, and ECU 50 causes battery SOC of power storage device 24 to be fully charged in step 112. By determining whether or not it is larger than a predetermined threshold value for determining charging, the “accumulation possibility determination unit” in the third aspect of the invention allows the allowable amount of regenerative power by the compressor 22 in the processing of step 112. The “allowable power setting means” in the third aspect of the present invention is realized by calculating

Embodiment 2. FIG.
[Features of Embodiment 2]
Next, a second embodiment of the present invention will be described with reference to FIG. The system of the present embodiment can be realized by causing the ECU 50 to execute a routine shown in FIG. 4 to be described later using the hardware configuration shown in FIG.

  In the above-described first embodiment, when compressor regeneration is performed, an allowable amount of regenerative power is set so that auxiliary devices such as the DC-DC converter 22 and the power storage device 24 are not damaged, and regenerative processing is performed within this range. Is going to do. Here, even within the allowable range, the regenerative process may not be executed depending on the state of the system. For example, when an abnormality such as damage occurs in the auxiliary devices such as the DC-DC converter 22 and the power storage device 24, even if the total power is within the allowable range, the damage is expanded by the compressor regeneration. There is a risk that. In addition, when the system power supply is cut off due to a vehicle collision or the like, there is a possibility that the compressor regeneration should be stopped to protect the system or the passenger.

  Therefore, in the second embodiment, when an abnormality occurs in the system auxiliary equipment, the compressor regeneration is prohibited. Thereby, the damage expansion of a system or auxiliary equipment can be suppressed.

[Specific Processing in Second Embodiment]
Next, with reference to FIG. 4, the specific content of the process performed in this Embodiment is demonstrated. FIG. 4 is a flowchart of a routine in which the ECU 50 executes the compressor regeneration process.

  In the routine shown in FIG. 4, first, the required power generation amount of the FC stack is calculated (step 200). Next, the target rotational speed of the compressor 20 is calculated (step 202). Next, it is determined whether or not the rotational speed of the compressor 20 is decelerated (step 204). Here, specifically, the same processing as steps 100 to 104 shown in FIG. 3 is executed.

  If it is determined in step 204 that the target rotational speed is not decelerated, it is determined that the compressor regeneration cannot be performed, and the process proceeds to the next step to calculate the target rotational speed of the compressor 22. Processing to increase the speed is executed, and this routine is terminated (step 206).

  On the other hand, if it is determined in step 204 that the target rotational speed of the compressor 20 is to be decelerated, it is determined that the compressor regeneration can be executed, and the process proceeds to the next step, in which the regeneration process by the compressor 20 is permitted. Various pieces of information for determining whether or not are detected (step 208). Here, specifically, various diagnostic signals for determining a system abnormality are detected.

  Next, it is determined whether or not compressor regeneration is permitted (step 210). Here, specifically, based on the diagnosis signal detected in the above step 208, an abnormality of the DC-DC converter 22, an abnormality of the power storage device 24, an abnormality of the compressor inverter 36, an abnormality such as a system power shutdown, etc. The presence or absence of is determined. As a result, when it is determined that some abnormality has occurred in the system, it is determined that the compressor regeneration should not be executed, and this routine is terminated without executing the regeneration process.

  On the other hand, if it is determined in step 210 that no abnormality has occurred in the system, it is determined that the compressor regeneration can be performed, and the process proceeds to the next step to perform the regeneration process (step 212). ). Specifically, when the rotational speed of the compressor 20 is reduced to the target rotational speed calculated in step 202, the compressor motor 34 is regeneratively driven to regenerate electric power.

  As described above, according to the system of the present embodiment, when the rotational speed of the compressor 20 is decelerated to the target rotational speed on the basis of a request for reducing the amount of oxidizing gas supplied to the FC stack 10, the system and its compensation are provided. If it is determined that an abnormality has occurred in the equipment, compressor regeneration is prohibited. Thereby, the situation where the damage etc. which have generate | occur | produced in the system and its auxiliary devices expand can be suppressed effectively.

  By the way, in Embodiment 2 described above, when it is determined that an abnormality has occurred in the system or its auxiliary devices, the compressor regeneration is prohibited. However, the operation at the time of abnormality is limited to the prohibition. I can't. In other words, the allowable input power of devices with abnormalities should be set lower than normal, and compressor regeneration should be performed within a range that does not exceed this, thereby reducing the burden on these abnormal devices. It is good.

  In the second embodiment described above, the oxidant gas supply compressor 20 disposed in the oxidant gas pipe 18 is used to regenerate power when the amount of oxidant gas reduction is requested, but it is used for power regeneration. The compressor to be used is not limited to this. That is, in a system including a hydrogen circulation pipe for circulating hydrogen off-gas in the FC stack 10 again and a hydrogen circulation compressor arranged in the hydrogen circulation pipe, the hydrogen circulation compressor is used to generate hydrogen. It is good also as regenerating electric power at the time of the reduction request | requirement of the circulation amount.

  Moreover, in Embodiment 2 mentioned above, it is good also as performing combining with the regeneration process in Embodiment 1. FIG.

  In the second embodiment described above, the FC stack 10 is in the “fuel cell” in the first invention, the oxidizing gas pipe 18 is in the “reaction gas flow path” in the first invention, and the compressor motor 34 is This corresponds to the “rotary electric machine” in the first invention. Further, the “regeneration means” and the “control means” in the first aspect of the present invention are realized by the ECU 50 executing the processing of step 212 described above.

  In the second embodiment described above, the “abnormality detection means” in the fourth or fifth aspect of the present invention is realized by the ECU 50 executing the processing of step 210 described above.

  In the second embodiment described above, the power storage device 24 is the “power storage device” in the sixth or seventh invention, the DC-DC converter 22 is the “converter” in the seventh invention, and the compressor inverter 36. Corresponds to the “inverter” in the eighth invention.

It is a figure for demonstrating the structure of the fuel cell system concerning Embodiment 1 of this invention. It is a figure which shows the change of the rotational speed when the deceleration process of the compressor 20 is performed. It is a flowchart of the routine performed in Embodiment 1 of the present invention. It is a flowchart of the routine performed in Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Fuel cell (FC) stack 12 Hydrogen gas piping 14 Hydrogen gas supply source 16 Pressure regulating valve 18 Oxidizing gas piping 20 Compressor 22 DC-DC converter 24 Power storage device 26 Traction motor 28 Drive shaft 30 Wheel 32 Traction motor inverter 34 Compressor motor 36 Compressor Inverter 50 ECU (Electronic Control Unit)
52 Voltmeter 54 Vehicle speed sensor 56 Accelerator opening sensor

Claims (9)

A fuel cell that receives a supply of fuel gas containing hydrogen at the anode and a power supply that receives supply of an oxidizing gas containing oxygen at the cathode; and
A reaction gas flow path for supplying a reaction gas to the fuel cell;
A compressor disposed in the reaction gas flow path;
A rotating electrical machine that is connected to the drive shaft of the compressor and functions as a prime mover and a generator;
Regenerative means for regenerating electrical energy by driving the rotating electrical machine by the rotational force of the compressor when reducing the supply amount of the reactive gas;
An allowable power setting means for setting an allowable power of the fuel cell auxiliary devices;
Control means for controlling the regenerative power by the regenerative means so that the power input to the auxiliary devices is less than or equal to the allowable power;
A fuel cell system comprising: The auxiliary devices include a converter interposed between the fuel cell and a power storage device for storing electric power,
The control means controls the regenerative power by the regenerative means so that the difference between the total power generated and regenerated in the fuel cell system and the power consumed in the fuel cell system is equal to or less than the allowable power. The fuel cell system according to claim 1. The auxiliary devices include a power storage device for storing electric power,
The battery further comprises power storage availability determination means for determining whether power can be stored in the power storage device,
3. The fuel cell system according to claim 1, wherein the allowable power setting unit sets the allowable power of the power storage device to zero when it is determined that the power storage device is in a state where it cannot store power. It further comprises an abnormality detection means for detecting an abnormality of the auxiliary devices,
4. The fuel according to claim 1, wherein the allowable power setting unit sets the allowable power of the auxiliary device in which an abnormality is detected by the abnormality detection unit to be lower than that in a normal state. 5. Battery system. It further comprises an abnormality detection means for detecting an abnormality of the auxiliary devices,
4. The fuel cell system according to claim 1, wherein when the abnormality is detected, the control unit prohibits a regenerative operation by the regenerative unit. 5. The auxiliary devices include a power storage device for storing electric power,
6. The fuel cell system according to claim 4, wherein the abnormality detection unit detects an abnormality of the power storage device. The auxiliary devices include a converter interposed between the fuel cell and a power storage device for storing electric power,
The fuel cell system according to claim 4 or 5, wherein the abnormality detection means detects an abnormality of the converter. The auxiliary devices include an inverter interposed between the fuel cell and the rotating electrical machine,
6. The fuel cell system according to claim 4, wherein the abnormality detection unit detects an abnormality of the inverter.   6. The fuel cell system according to claim 4 or 5, wherein the abnormality detection means detects a power shutoff abnormality of the fuel cell system.

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