JP2003109627A - Control device for fuel cell vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent rise of hydrogen gas pressure in a fuel cell stack even when the load is suddenly reduced. SOLUTION: A purge valve 19 is controlled and kept open by outputting a control signal from a controller 4 to an actuator 20 in accordance with the drop in demand power which is the power generation demand to a fuel cell stack 11, whereby a fuel gas for fuel gas pressure raised in a hydrogen pole 11a is released from the purge valve 19. That is, the increase of the pressure difference between the hydrogen gas pressure of the hydrogen pole 11a and the air pressure of an oxygen pole 11b can be prevented by releasing the hydrogen gas for reduction of the hydrogen gas consumption in the hydrogen pole 11a caused by the drop of the drive power of the load, from the hydrogen pole 11a by the purge valve 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a fuel cell vehicle which controls a fuel gas pressure in a fuel cell stack for generating electric power supplied to a motor which is a drive source of the vehicle.

[0002]

2. Description of the Related Art Conventionally, a fuel cell system supplies air as an oxidant gas and hydrogen as a fuel gas to generate electric power in a fuel cell stack, for example, to drive a motor serving as a drive source of a vehicle. Known as one. The hydrogen passage of this fuel cell system is usually provided with one or more valves for controlling hydrogen pressure and circulating hydrogen, and is a closed system (Japanese Patent Laid-Open No. 8- 195210).

Accordingly, in the fuel cell system, the hydrogen pressure in the hydrogen electrode of the fuel cell stack is controlled to control the operation of the fuel cell stack, and the hydrogen discharged from the fuel cell stack is supplied to the fuel cell stack. It circulates to the side to effectively use hydrogen.

In such a fuel cell system, when the load of the motor, which is the drive source of the vehicle, decreases stepwise, the electric power that needs to be generated by the fuel cell decreases stepwise, and the fuel cell stack Hydrogen consumption decreases sharply. Therefore, the pressure of the hydrogen electrode of the fuel cell stack increases. If the state where the pressure of the hydrogen electrode is increased is left as it is, there is a possibility that the function of the fuel cell stack may be deteriorated due to the high pressure.

In order to deal with such a sudden load change of the motor, the fuel cell system disclosed in Japanese Patent Laid-Open No. 2-309562 uses the hydrogen gas supply passage in the normal operation of the fuel cell stack. In addition to the flow rate control valve, a high-speed on-off valve with high responsiveness of operation is provided. Then, in this fuel cell system, when the load on the motor decreases, the high-speed on-off valve is instantaneously closed so as to prevent hydrogen gas from being supplied to the hydrogen electrode of the fuel cell stack more than necessary.

[0006]

By the way, in the fuel cell system, the hydrogen flow path is a closed system. Therefore, in order to maintain the hydrogen gas pressure at the hydrogen electrode at a constant value, the hydrogen gas at the hydrogen electrode must be kept constant. The amount of hydrogen gas supplied to the hydrogen electrode via the pressure control valve for controlling the gas pressure and the amount of hydrogen gas consumed in the fuel cell stack must be the same.

In the conventional fuel cell system, the high-speed on-off valve is opened and closed instantaneously in response to a sudden change in load, but it is impossible to actually open and close it instantaneously. Therefore, even after the motor load drops sharply and the hydrogen gas consumption decreases, the hydrogen gas continues to be supplied to the hydrogen electrode during the period from the open state to the closed state of the high-speed on-off valve. , The hydrogen gas pressure at the hydrogen electrode rises.

Even after the high-speed on-off valve is closed, the hydrogen gas pressure does not increase, but the increased hydrogen gas pressure is retained before the high-speed on-off valve is closed. In such a state, the pressure difference between the hydrogen electrode and the oxygen electrode of the fuel cell stack becomes excessively large, which may deteriorate the function of the polymer membrane inside the fuel cell stack.

Therefore, the present invention has been proposed in view of the above-mentioned circumstances, and it is possible to prevent the hydrogen gas pressure from increasing in the fuel cell stack even when the load sharply decreases. An object of the present invention is to provide a control device for a fuel cell vehicle that can be used.

[0010]

In order to solve the above-mentioned problems, in the invention according to claim 1, an electrolyte membrane is sandwiched between an oxidant electrode and a fuel electrode, and the oxidant is provided on the oxidant electrode side. Gas is supplied to the fuel electrode side, and the fuel gas is supplied to the fuel electrode side to generate electric power, and the generated electric power is supplied to a motor serving as a drive source of a vehicle, and an oxidant gas is supplied to the fuel cell. The oxidant gas supply means, the fuel gas supply means for supplying the fuel gas to the fuel cell, and the insertion tube on the fuel gas discharge side of the fuel cell are provided to discharge the fuel gas discharged from the fuel cell to the outside. In a control device for a fuel cell vehicle including a release valve for controlling the fuel cell vehicle, the release valve is opened in response to a decrease in required generated power, which is the generated power required for the fuel cell. Take control and up Elevated fuel gas pressure fraction of the fuel gas in the fuel in-electrode, characterized in that it comprises control means for releasing from the release valve.

According to a second aspect of the present invention, in the invention according to the first aspect, the fuel cell vehicle has a traction control system for performing a driving force reducing operation for reducing the driving force of the driving wheels of the vehicle according to the vehicle state. However, the control device determines that the required generated power has decreased in accordance with the driving force reduction operation by the traction control system, and controls the release valve to be in an open state.

According to a third aspect of the present invention, in the second aspect of the present invention, the control device opens the release valve in response to cancellation of the driving force lowering operation by the traction control system. It is characterized in that it is controlled to be closed from.

The invention according to claim 4 is the invention according to claim 2 or claim 3, wherein the control device includes the state of the fuel cell before the driving force reducing operation by the traction control system and the traction control. The operation amount of the release valve when the release valve is opened is determined based on the amount of decrease in the drive force of the motor due to the drive force reduction operation of the system.

[0014]

According to the first aspect of the present invention, the release valve is controlled to open in response to a decrease in the required generated electric power, which is the generated electric power required for the fuel cell, so that the inside of the fuel electrode is controlled. Since the fuel gas corresponding to the increased fuel gas pressure is released from the release valve, it is possible to prevent the fuel gas pressure from increasing in the fuel electrode even when the driving force of the motor sharply decreases. .

According to the second aspect of the present invention, it is determined that the required generated electric power has decreased in accordance with the driving force lowering operation by the traction control system, and the discharge valve is opened. Therefore, the traction control causes the motor driving force to be reduced. Even if the value of the fuel cell drops sharply, the fuel gas pressure in the fuel electrode is prevented from rising, and the pressure difference between the fuel electrode and the oxidizer electrode becomes excessive. It is possible to avoid degrading the function of the membrane.

By the way, since the operation of the release valve releases the fuel gas without using it for power generation, if it is operated more than necessary, fuel consumption is deteriorated. For example, even if the required power generation amount decreases, if the decrease speed is very small, the fuel gas pressure will not increase in the fuel electrode without opening the release valve, Even in such a case, opening the release valve may lead to deterioration of fuel efficiency.

Therefore, it is conceivable to calculate the rate of decrease in the required power generation amount and control the release valve in accordance with this, but when the required power generation amount drops suddenly such that the release valve must be opened, The release valve should be opened as soon as possible, and the response will be delayed after the rate of decrease in the required power generation amount is calculated.

In the present invention, the required power generation amount suddenly drops in many cases when the traction control system is in operation. Therefore, the release valve is controlled by using this operation signal to calculate the reduction rate of the required power generation amount. It is possible to open the release valve only when it should be truly opened, so that deterioration of fuel efficiency can be suppressed.

According to the invention of claim 3, the release valve is changed from the open state to the closed state in response to the cancellation of the driving force lowering operation by the traction control system. In addition, the fuel gas pressure at the fuel electrode of the fuel cell can be quickly returned to the fuel gas pressure before the operation of the traction control system.

According to the fourth aspect of the invention, the release valve is based on the state of the fuel cell before the driving force lowering operation by the traction control system and the amount of reduction of the motor driving force by the driving force lowering operation of the traction control system. Since the operation amount of the release valve when the valve is opened is determined, the fuel gas pressure of the fuel electrode can be controlled more accurately. Therefore, according to the invention of claim 4, even when the driving force of the motor is drastically changed and the fuel gas consumption is drastically changed, the fuel gas pressure and the air pressure in the fuel cell are The pressure difference can be further reduced.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

The present invention is applied to a fuel cell vehicle constructed as shown in FIG. 1, for example.

[Structure of Fuel Cell Vehicle] As shown in FIG. 1, this fuel cell vehicle is equipped with a fuel cell system 1, an inverter 2 and a drive motor 3, and the fuel cell system 1 and the inverter 2 are connected to a controller 4. The drive motor 3 is driven by controlling with.

In the fuel cell system 1, a solid polymer electrolyte membrane is sandwiched between an oxygen electrode 11b (oxidant electrode) and a hydrogen electrode 11a (fuel electrode), and a plurality of fuel cell structures are laminated with a separator interposed therebetween. A fuel cell stack 11 having a stack structure is formed. This fuel cell stack
Hydrogen is released from the electron at the hydrogen electrode to ionize and pass through the solid polymer electrolyte membrane, and at the air electrode, oxygen and ionized hydrogen are combined to generate water to generate power.

The fuel cell system 1 supplies the generated electric power to the inverter 2. This fuel cell system 1
The operation of is controlled by a control signal from the controller 4. The configuration of the fuel cell system 1 will be described later.

The inverter 2 converts the DC power from the fuel cell system 1 into AC power and outputs it to the drive motor 3. The inverter 2 receives a motor torque command designating a motor torque from the controller 4 and supplies an alternating current corresponding to the motor torque command to the drive motor 3 to generate a motor torque designated by the drive motor 3.

Further, this fuel cell vehicle has a drive motor 3
A pair of drive wheels 5 mechanically connected to each other and a pair of driven wheels 6 not connected to the drive motor 3 are provided, and a motor torque generated by the drive motor 3 is transmitted to the tire to generate a driving force.

Further, the fuel cell vehicle is equipped with a drive wheel side vehicle speed sensor 7 at a mechanical connection portion between the drive motor 3 and the drive wheels 5. The drive wheel side vehicle speed sensor 7 detects the rotational speed of the drive wheel 5 and outputs it as a sensor signal to the controller 4. Further, this fuel cell vehicle is provided with a driven wheel side vehicle speed sensor 8 which is a mechanical connection portion of the pair of driven wheels 6. The driven wheel side vehicle speed sensor 8 detects the rotation speed of the driven wheel 6 and outputs it to the controller 4 as a sensor signal.

The controller 4 is normally inputted with a sensor signal such as an accelerator operation amount or a brake operation amount, and calculates a motor torque amount required for the drive motor 3 based on the sensor signal. Then, the controller 4 controls the amount of generated electric power in the fuel cell system 1 and also controls the amount of AC electric power supplied from the inverter 2 to the drive motor 3 in order to realize the required motor torque amount. Drive.

Further, the controller 4 receives a sensor signal from the driving wheel side vehicle speed sensor 7 and the driven wheel side vehicle speed sensor 8 and changes a motor torque amount based on the sensor signal.
ol System: TCS).

Specifically, the controller 4 controls the rotational speed of the drive wheel 5 according to the sensor signal from the drive wheel side vehicle speed sensor 7 and the driven wheel 6 according to the sensor signal from the driven wheel side vehicle speed sensor 8. The speed difference from the rotation speed is calculated, and the torque reduction amount of the drive wheels 5 is determined according to the speed difference. The controller 4 calculates so that the torque reduction amount is increased as the rotation speed of the drive wheels 5 is higher than the rotation speed of the driven wheels 6.

Further, the controller 4 generates a torque down command indicating that the AC power amount supplied from the inverter 2 to the drive motor 3 is reduced according to the determined torque down amount, and outputs it to the inverter 2. The controller 4 also outputs a torque down command and an open command for opening the purge valve 19 of the fuel cell system 1.

Furthermore, the controller 4 operates the inverter 2 in response to the torque down command, so that the motor torque amount of the drive motor 3 decreases, and the traction control does not operate to return the motor torque amount to the original value. When it is set to (release), the inverter 2 outputs a command to supply AC power to the drive motor 3. At the same time, the controller 4 outputs a close command for closing the purge valve 19 of the fuel cell system 1 described later.

[Structure of Fuel Cell System 1] FIG. 2 shows the structure of the fuel cell system 1.

The fuel cell system 1 includes a hydrogen storage cylinder 12 that stores hydrogen serving as hydrogen gas (fuel gas).
And a hydrogen gas pressure adjusting valve 14 provided in the hydrogen gas supply passage 13. A first actuator 15 for adjusting the opening degree is connected to the hydrogen gas pressure adjusting valve 14. The first actuator 15 adjusts the opening degree of the hydrogen gas pressure adjusting valve 14 according to the control signal from the controller 4.

In this fuel cell system 1, the hydrogen electrode 11 is adjusted by adjusting the opening of the hydrogen gas pressure adjusting valve 14.
Control the hydrogen gas pressure in a.

On the gas discharge side of the hydrogen electrode 11a of the fuel cell stack 11, there is provided a hydrogen circulation return passage 16 for returning the exhaust gas from the hydrogen electrode 11a of the fuel cell stack 11 to the hydrogen gas supply passage 13 again. ing. In addition, in the fuel cell system 1, at the connecting portion between the hydrogen circulation / recirculation passage 16 and the hydrogen gas supply passage 13, the hydrogen gas from the hydrogen circulation / recirculation passage 16 is supplied to the hydrogen gas supply port of the fuel cell stack 11. A pump pump 17 is provided.

Further, the hydrogen electrode 11 of the fuel cell stack 11
On the gas discharge side of a, a purge valve 19 for discharging hydrogen gas and water vapor to the outside through the hydrogen gas discharge channel 18 is provided.
(Discharge valve) is provided. The purge valve 19 is an open / close valve whose open / close state is controlled by the controller 4. A second actuator 20 for opening / closing the purge valve 19 is connected to the purge valve 19. The second actuator 20 opens and closes the purge valve 19 according to a control signal from the controller 4.

In the fuel cell system 1 as described above, in order to stabilize the cell voltage of the fuel cell stack 11, the hydrogen gas has a stoichiometric ratio (supply hydrogen gas flow rate / consumed hydrogen gas flow rate) of 1 or more. Excess hydrogen gas that cannot be consumed at the electrode 11a is supplied again to the hydrogen electrode 11a of the fuel cell stack 11.

The purge valve 19 is not limited to an opening / closing valve, but may be an opening adjustment valve capable of adjusting the opening.

Further, in the fuel cell system 1, a hydrogen combustor 21 connected to a hydrogen gas discharge passage 18 via a purge valve 19 is provided on the gas discharge side of the hydrogen electrode 11a of the fuel cell stack 11.

Furthermore, the fuel cell system 1 is equipped with a compressor 22 which sucks in air (oxidant gas) from the outside and compresses it, and supplies the air to the oxygen electrode 11b of the fuel cell stack 11. The rotation speed of the compressor 22 is controlled by the controller 4 so that the compressor 22 has a predetermined flow rate according to the operating state of the fuel cell stack 11, for example. Further, the air taken in by the compressor 22 is supplied to the oxygen electrode 11b of the fuel cell stack 11 through the air supply flow path 23.

Furthermore, in the fuel cell system 1, an air pressure adjusting valve 25 is provided on the air discharge side of the fuel cell stack 11 via an air discharge passage 24. A third actuator 26 for adjusting the opening is connected to the air pressure adjusting valve 25. The third actuator 26 is
The opening of the air pressure adjusting valve 25 is adjusted according to the control signal from the controller 4.

In this fuel cell system 1, the air pressure in the oxygen electrode 11b is controlled by adjusting the opening of the air pressure adjusting valve 25.

Further, at the hydrogen gas supply port of the fuel cell stack 11, a hydrogen pressure sensor 2 for detecting hydrogen gas pressure is provided.
7 is provided, and an air pressure sensor 28 that detects the air pressure is provided at the air supply port of the fuel cell stack 11. Then, the hydrogen pressure sensor 27 and the air pressure sensor 28 output the detected hydrogen gas pressure and air pressure to the controller 4 as sensor signals.

In such a fuel cell system 1,
The controller 4 refers to the sensor signal from the air pressure sensor 28, controls the third actuator 26 so as to obtain the air pressure that generates the generated power according to the required motor torque amount, and controls the third air pressure control valve 25. Adjust the opening.

Further, in this fuel cell system 1,
The controller 4 refers to the sensor signal from the hydrogen pressure sensor 27, controls the first actuator 15 so that the hydrogen gas pressure that generates electric power according to the required motor torque amount, and controls the hydrogen gas pressure adjusting valve 14 Adjust the opening of.

[Processing of Controller 4] "First Processing Example"
FIG. 3 shows a flowchart of the processing procedure of the first processing example of the controller 4 described above.

When the fuel cell system 1 is operating, the controller 4 starts the processing of step S1 and thereafter by performing the processing shown in FIG. 3, for example, every predetermined time.

In step S1, a sensor signal from a cell voltage sensor (not shown) for detecting the cell voltage of the fuel cell stack 11 is input, and the controller 4 determines whether or not water is clogged in the fuel cell stack 11. To do. For example, if it is determined that the water is clogged due to the decrease in the cell voltage, the process proceeds to step S2, and if it is determined that the water is not clogged, the process proceeds to step S3.

In step S2, the fuel cell stack 11
Controller 4 to eliminate water clogging
Thus, the second actuator 20 is controlled so that the purge valve 19 is opened for a predetermined time, and the process is ended.

In step S3, the controller 4 determines whether to activate the traction control based on the sensor signals from the driving wheel side vehicle speed sensor 7 and the driven wheel side vehicle speed sensor 8.

When it is determined in step S3 that the traction control is to be activated, the process proceeds to step S4, and the controller 4 controls the second actuator 20 to open the purge valve 19. At the same time, the controller 4 outputs a torque down command to the inverter 2.

When it is determined in step S3 that the traction control is not activated, the process proceeds to step S5, the purge valve 19 is kept closed, and the process ends.

In the fuel cell vehicle equipped with the controller 4 for performing such processing, as shown in FIG. 4, when the traction control is activated by the determination in step S3 at time t1, a torque down command is output to the inverter 2. As a result, the motor torque of the drive motor 3 sharply decreases (FIG. 4A).

At time t1, the torque down command is output from the controller 4 to the inverter 2, so that the AC current supplied from the inverter 2 to the drive motor 3 is rapidly reduced, and the load current of the drive motor 3 is rapidly reduced. (Fig. 4 (b)). That is, the fuel cell stack 11
Since the amount of direct-current power output from the inverter 2 to the inverter 2 sharply decreases, the amount of hydrogen gas consumed at the hydrogen electrode 11a sharply decreases.

On the other hand, as described above, when the torque down command is output to the inverter 2, at the same time as the purge valve 1 is output.
By opening 9 (FIG. 4 (d)), excess hydrogen gas that has not been consumed by the hydrogen electrode 11a is released as the motor torque decreases sharply.

When the operation of the traction control is released at time t2 (FIG. 4 (a)), the inverter 2
By outputting the motor torque command to the hydrogen electrode 11a
The hydrogen gas consumption of the above increases (FIG. 4B), and at the same time, the purge valve 19 is changed from the open state to the closed state (FIG. 4D).

As a result, as shown in FIG. 4 (c), even if the motor torque amount sharply decreases, it is possible to prevent the hydrogen gas pressure from increasing in the hydrogen electrode 11a. Therefore, according to this fuel cell system 1, by operating the traction control system, the pressure difference between the hydrogen electrode 11a and the oxygen electrode 11b of the fuel cell stack 11 becomes excessively large, and the inside of the fuel cell stack 11 becomes high. It is possible to avoid degrading the function of the molecular film.

Further, when the traction control is released, the purge valve 19 is simultaneously changed from the open state to the closed state. Therefore, the hydrogen gas pressure of the hydrogen electrode 11a of the fuel cell stack 11 is promptly changed before the traction control system is activated. It can be returned to hydrogen gas pressure.

On the other hand, FIG. 5 shows changes with time in the motor torque, hydrogen gas consumption amount, and hydrogen gas pressure when the purge valve 19 is not opened when the traction control is operated. Similar to the case shown in FIG. 4, time t11
When the motor torque is drastically reduced by operating the traction control at (5 (a)), the hydrogen gas consumption amount at the hydrogen electrode is drastically reduced ((5)).

At this time, in the case where the pressure of the hydrogen gas in the hydrogen electrode is adjusted by the pressure adjusting valve provided on the hydrogen gas supply side of the fuel cell stack, as shown by the characteristic A in FIG. Despite the decrease in gas consumption, the hydrogen gas pressure is increased by supplying hydrogen gas to the hydrogen electrode during the period until the pressure control valve is closed. This causes a pressure difference between the air gas pressure and the hydrogen gas pressure. Then, at time t12, when the traction control is deactivated and the hydrogen gas consumption increases (FIGS. 5A and 5B), the consumption of hydrogen gas is restarted at the hydrogen electrode and the hydrogen gas pressure gradually decreases. Yes (Fig. 5
(C)).

When a high-speed on-off valve is provided on the hydrogen gas supply side of the fuel cell stack in addition to the pressure control valve, the high-speed on-off valve is closed after the traction control starts operating at time t11. As shown by the characteristic B in FIG. 5C, time t13 delayed from time t11.
The high-speed on-off valve closes. Even when the high-speed on-off valve is used in this way, hydrogen gas is not supplied to the hydrogen electrode until the high-speed on-off valve closes, and the pressure difference between the air gas pressure and the hydrogen gas pressure is Occurs at time t1
After 3, the hydrogen gas pressure is held with a pressure difference.

On the other hand, as described above, when the hydrogen gas consumption amount is drastically reduced, the purge valve 19 provided on the hydrogen gas discharge side of the fuel cell stack 11 is opened so that the hydrogen gas pressure You can avoid rising.

Even if the purge valve 19 cannot be opened and closed instantaneously and the hydrogen gas pressure rises, the purge valve 1
When 9 starts to open, the action of returning the hydrogen gas pressure to the original pressure value can be realized, and the amount of hydrogen gas discharged from the purge valve 19 can be increased by the amount of increase in the hydrogen gas pressure at the hydrogen electrode. it can.

[Second Processing Example] FIG. 6 shows a flowchart of the processing procedure of the second processing example of the controller 4 described above.
The same steps as those in the above-described first processing example will be denoted by the same step numbers, and detailed description thereof will be omitted.

In the second processing example, if it is determined in step S3 that the traction control is activated, step S1
The process proceeds to 1 and the controller 4 calculates the reduction amount of the hydrogen gas consumption amount due to the activation of the traction control. At this time, the controller 4 calculates the reduction amount of the hydrogen gas consumption amount by converting the torque reduction amount by the traction control. here,
When the fuel cell stack 11 is operating at the hydrogen gas consumption amount shown by ◯ in FIG. 7A, the reduction amount of the hydrogen gas consumption amount varies depending on the torque reduction amount.

In the next step S12, in order to maintain the hydrogen gas pressure at the hydrogen electrode 11a at the pressure value before the torque down command is output, the controller 4 calculates the hydrogen gas consumption amount which is reduced by the torque down amount. In order to discharge from the purge valve 19, the operation amount when the purge valve 19 is opened is calculated.

Assuming that the hydrogen gas pressure before the torque down command is output is 0.3 MPa, the hydrogen gas pressure at the hydrogen gas supply port of the fuel cell stack 11 as shown in FIG. From the relationship with the passing hydrogen gas flow rate,
The purge valve operation amount for discharging the hydrogen gas consumption amount that decreases with the torque reduction amount at the hydrogen gas pressure at the hydrogen gas supply port is calculated.

When the hydrogen gas pressure before the torque down command is output is 0.3 MPa and the reduction amount of the hydrogen gas consumption amount corresponding to the first torque down amount becomes as shown in FIG. 7 (a). As shown in FIG. 7B, the opening degree of the purge valve 19 for releasing the hydrogen gas consumption decrease amount from the purge valve 19 becomes the first purge valve operation amount of FIG. 7B. Further, regarding the second torque reduction amount and the third torque reduction amount, the second torque reduction amount shown in FIGS. 7A and 7B is also used.
It is the purge valve operating amount and the third purge valve operating amount.

In the next step S13, the control signal is output from the controller 4 to the third actuator 26, and the purge valve 19 is operated by the operation amount calculated in step S12.
Control to open.

According to the fuel cell vehicle equipped with the controller 4 for performing such processing, based on the hydrogen gas pressure at the hydrogen electrode 11a before the torque down command is output and the torque down amount according to the torque down command. , Purge valve 19
Therefore, the hydrogen gas pressure of the hydrogen electrode 11a can be controlled more accurately. Therefore, in this fuel cell vehicle, even if the motor torque drastically changes and the hydrogen gas consumption drastically changes, the pressure difference between the hydrogen gas pressure and the air pressure in the fuel cell stack 11 is further increased. Can be made smaller.

The above-described embodiment is an example of the present invention. For this reason, the present invention is not limited to the above-described embodiment, and other than this embodiment, as long as it does not deviate from the technical idea of the present invention, various types according to the design etc. Of course, it is possible to change.

That is, in the fuel cell vehicle to which the present invention is applied, the purge valve is opened when the torque down command is generated by the traction control system, but the invention is not limited to this. For example, the accelerator opening sharply decreases. Even in this case, the purge valve can be opened to prevent the hydrogen electrode pressure from rising.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a fuel cell vehicle to which the present invention is applied.

FIG. 2 is a diagram showing a configuration of a fuel cell system in a fuel cell vehicle to which the present invention is applied.

FIG. 3 is a flowchart showing a processing procedure in a first processing example of a controller that controls a fuel cell vehicle to which the present invention is applied.

FIG. 4 is a time chart showing the operation of the fuel cell vehicle to which the present invention is applied when the traction control system operates, where (a) is the motor torque, and (b) is the current supplied to the drive motor (hydrogen gas consumption). (Amount), (c) shows the hydrogen gas pressure and air pressure at the hydrogen electrode, and (d) shows the operating state of the purge valve.

5A and 5B are time charts showing an operation as a comparative example when the traction control system operates, where FIG. 5A is a motor torque, FIG. 5B is a current supplied to a drive motor (hydrogen gas consumption amount), and FIG. ) Indicates hydrogen gas pressure and air pressure at the hydrogen electrode.

FIG. 6 is a flowchart showing a processing procedure in a second processing example of a controller for controlling a fuel cell vehicle to which the present invention is applied.

FIG. 7 is a diagram for explaining that the purge valve operation amount is determined according to the torque reduction amount in the fuel cell vehicle to which the present invention is applied, and (a) is a current value and hydrogen gas in the fuel cell stack. FIG. 6B is a diagram showing a relationship between the amount of hydrogen gas at the hydrogen gas supply port of the fuel cell stack and a purge valve passage flow rate.

[Explanation of symbols]

1 Fuel cell system 2 inverter 3 drive motor 4 controller 5 drive wheels 6 driven wheel 7 Drive wheel side vehicle speed sensor 8 Driven wheel side vehicle speed sensor 11 Fuel cell stack 11a Hydrogen electrode 11b oxygen pole 12 Hydrogen storage cylinder 13 Hydrogen gas supply channel 14 Hydrogen gas pressure control valve 15 First actuator 16 Hydrogen circulation / reflux path 17 executor pump 18 Hydrogen gas discharge channel 19 Purge valve 20 Second actuator 21 Hydrogen combustor 22 Compressor 23 Air supply flow path 24 Air discharge channel 25 Air pressure control valve 26 Third Actuator 27 Hydrogen pressure sensor 28 Air pressure sensor

Claims (4)

[Claims] 1. An electrolyte membrane is sandwiched between an oxidant electrode and a fuel electrode. The oxidant gas is supplied to the oxidant electrode side and the fuel gas is supplied to the fuel electrode side to generate electricity. A fuel cell that supplies the generated electric power to a motor that serves as a drive source for the vehicle; an oxidant gas supply unit that supplies an oxidant gas to the fuel cell; and a fuel gas supply unit that supplies a fuel gas to the fuel cell. A fuel cell vehicle control device for controlling a fuel cell vehicle, comprising: a release valve that is provided in a fuel gas discharge side insertion tube of the fuel cell and that discharges the fuel gas discharged from the fuel cell to the outside, The release valve is controlled to open in response to a decrease in the required generated power, which is the generated power required for the fuel cell, and the amount of fuel gas corresponding to the increased fuel gas pressure in the fuel electrode is set to the above value. Released from the release valve Control apparatus for a fuel cell vehicle, characterized in that it comprises control means that. 2. The fuel cell vehicle has a traction control system that performs a driving force reduction operation for reducing driving force of driving wheels of the vehicle according to a vehicle state, and the control device is driven by the traction control system. The control device for a fuel cell vehicle according to claim 1, wherein it is determined that the required generated power has decreased in accordance with a force reduction operation, and control is performed to open the release valve. 3. The control device controls the release valve from an open state to a closed state in response to the driving force lowering operation by the traction control system being canceled. A control device for a fuel cell vehicle according to item 1. 4. The control device is based on the state of the fuel cell before the driving force reducing operation by the traction control system and the amount of reduction of the driving force of the motor by the driving force reducing operation of the traction control system. The control device for a fuel cell vehicle according to claim 2 or 3, wherein an operation amount of the release valve when the release valve is opened is determined.