JP2021051960A - Fuel cell vehicle - Google Patents

Abstract

To provide a fuel cell vehicle that suppresses the waste of energy while suppressing the deterioration of the power generation performance of a fuel cell.SOLUTION: A fuel cell vehicle includes a fuel cell, a supply device that supplies reaction gas to the fuel cell, a switch that can be operated manually, an acquisition device that acquires stop position information, and a control device that controls the power generation state of the fuel cell and the supply device, and in a case in which there is a request to stop the power generation of the fuel cell, the control device stops the power generation of the fuel cell, and stops the supply device when the switch is off, continues or stops the power generation of the fuel cell to continue driving the supply device when the switch is on and the position is other than a predetermined position, and steps the power generation of the fuel cell, and turns off the switch to stop the supply device when the switch is on and the stop position is the predetermined position.SELECTED DRAWING: Figure 2

Description

The present invention relates to a fuel cell vehicle.

Patent Document 1 discloses a technique capable of switching between a stop mode in which the fuel cell power generation is stopped and then promptly purged, and a standby mode in which the fuel cell is not purged until a predetermined time has elapsed (see Patent Document 1).

Japanese Unexamined Patent Publication No. 2006-12385

For example, when a vehicle equipped with a fuel cell is a delivery truck, it may be frequently repeated to stop for a short time for loading and unloading luggage and start running again. In this case, as the fuel cell generates, stops, and restarts, the supply of the reaction gas is repeatedly stopped and restarted in a short period of time, increasing the chance that the potential of the fuel cell fluctuates greatly, and the power generation performance of the fuel cell improves. May decrease. Therefore, in such a case, it is conceivable to execute control for suppressing the fluctuation of the potential of the fuel cell. However, if the above control is executed even when the vehicle is stopped for a long time, energy is wasted accordingly.

An object of the present invention is to provide a fuel cell vehicle that suppresses waste of energy while suppressing deterioration of power generation performance of the fuel cell.

The above objectives are a fuel cell, a supply device for supplying reaction gas to the fuel cell, a switch that can be manually operated, an acquisition device for acquiring information on a stop position, a power generation state of the fuel cell, and the supply device. In a fuel cell vehicle provided with a control device for controlling the fuel cell, the control device stops the power generation of the fuel cell when the switch is off when there is a request to stop the power generation of the fuel cell. When the supply device is stopped and the switch is on and the stop position is other than the predetermined position, the power generation of the fuel cell is continued or stopped to continue driving the supply device, and the switch is on. This can be achieved by a fuel cell vehicle in which when the stop position is a predetermined position, the power generation of the fuel cell is stopped, the switch is turned off, and the supply device is stopped.

According to the present invention, it is possible to provide a fuel cell vehicle that suppresses waste of energy while suppressing deterioration of power generation performance of the fuel cell.

FIG. 1 is a schematic configuration diagram of a fuel cell vehicle. FIG. 2 is a flowchart showing an example of control executed by the ECU.

[Fuel cell vehicle configuration]
FIG. 1 is a schematic configuration diagram of a fuel cell vehicle 1 (hereinafter referred to as a vehicle 1). The vehicle 1 includes an ECU (Electronic Control Unit) 3, a fuel cell (hereinafter referred to as FC) 4, a secondary battery (hereinafter referred to as BAT) 8, a cathode gas supply system 10, an anode gas supply system 20, and electric power control. Includes system 30. The vehicle 1 includes a cooling system (not shown) that circulates cooling water in the FC4 to cool the vehicle. Further, the vehicle 1 is provided with a traveling motor 50, an ignition switch 2, wheels 5, an accelerator opening sensor 6, a stop / standby switch 7 described later, and a navigation device 9. The FC4 is a fuel cell that generates electricity by receiving the supply of a cathode gas and an anode gas, and is configured by stacking a plurality of solid polymer electrolyte type single cells.

The cathode gas supply system 10 supplies air containing oxygen as a cathode gas to the FC4, and supplies the supply pipe 11, the discharge pipe 12, the bypass pipe 13, the air compressor 14, the three-way valve 15, the intercooler 16, the back pressure valve 17, and the humidification. Includes vessel 18. The supply pipe 11 is connected to the cathode inlet manifold of FC4. The discharge pipe 12 is connected to the cathode outlet manifold of FC4. The bypass pipe 13 communicates the supply pipe 11 and the discharge pipe 12. The three-way valve 15 is provided at a connecting portion between the supply pipe 11 and the bypass pipe 13. The three-way valve 15 switches the communication state between the supply pipe 11 and the bypass pipe 13. The air compressor 14, the three-way valve 15, and the intercooler 16 are arranged on the supply pipe 11 in order from the upstream side. The back pressure valve 17 is located on the discharge pipe 12 and is arranged on the upstream side of the connection portion between the discharge pipe 12 and the bypass pipe 13. The humidifier 18 is provided over the supply pipe 11 and the discharge pipe 12. Specifically, the humidifier 18 is provided on the supply pipe 11 on the downstream side of the intercooler 16 and discharges on the upstream side of the back pressure valve 17. It is provided on the pipe 12.

The air compressor 14 supplies air containing oxygen as a cathode gas to the FC 4 via the supply pipe 11. The cathode gas supplied to FC4 is discharged through the discharge pipe 12. The intercooler 16 cools the cathode gas supplied to the FC4. The back pressure valve 17 adjusts the back pressure on the cathode side of FC4. The drive of the air compressor 14, the three-way valve 15, and the back pressure valve 17 is controlled by the ECU 3. The ECU 3 can adjust the flow rate of the cathode gas supplied to the FC 4 by controlling the rotation speed of the air compressor 14. Further, the ECU 3 can adjust the flow rate of the cathode gas supplied to the FC4 and the flow rate of the cathode gas to be bypassed by controlling the opening degree of the three-way valve 15 and the back pressure valve 17. The humidifier 18 uses the water in the cathode off gas discharged from the FC4 flowing through the discharge pipe 12 to humidify the cathode gas before being supplied to the FC4 flowing through the supply pipe 11. A moisture permeable film is provided in the humidifier 18 so as to partition the flow path through which the cathode gas flows and the flow path through which the cathode off gas flows, and the moisture in the cathode off gas passes through the moisture permeable film on the cathode gas side. The cathode gas is humidified by permeating through. Instead of the three-way valve 15, a sealing valve may be provided on the supply pipe 11 and a flow dividing valve may be provided on the bypass pipe 13.

The anode gas supply system 20 supplies hydrogen gas to FC4 as an anode gas, and tank 20T, supply pipe 21, discharge pipe 22, circulation pipe 23, tank valve 24, pressure regulating valve 25, injector (hereinafter referred to as INJ) 26. , A gas-liquid separator 27, a drain valve 28, and a hydrogen circulation pump (hereinafter referred to as HP) 29. The anode inlet manifold of the tank 20T and FC4 is connected by a supply pipe 21. Hydrogen gas, which is an anode gas, is stored in the tank 20T. One end of the discharge pipe 22 is connected to the anode outlet manifold of FC4, and the other end of the discharge pipe 22 is connected to the discharge pipe 12 of the oxidant gas supply system 10. The circulation pipe 23 communicates the gas-liquid separator 27 with the supply pipe 21. The tank valve 24, the pressure regulating valve 25, and the INJ26 are arranged in order from the upstream side of the supply pipe 21.

With the tank valve 24 open, the opening degree of the pressure regulating valve 25 is adjusted, and the INJ 26 injects the anode gas. As a result, the anode gas is supplied to FC4. A gas-liquid separator 27 and a drain valve 28 are arranged in the discharge pipe 22 in order from the upstream side. The gas-liquid separator 27 separates and stores water from the anode gas discharged from FC4. The water stored in the gas-liquid separator 27 is discharged to the outside of the vehicle 1 through the discharge pipe 22 by opening the drain valve 28. The circulation pipe 23 is a pipe for returning the anode gas to FC4, and the upstream end is connected to the gas-liquid separator 27, and the HP 29 is arranged. The anode gas discharged from FC4 is appropriately pressurized by HP29 and guided to the supply pipe 21. The drive of the tank valve 24, the pressure regulating valve 25, the INJ26, the drain valve 28, and the HP29 is controlled by the ECU 3. An ejector may be provided instead of the HP29, and the anode gas discharged from the FC4 may be resupplied to the supply pipe 21 by the ejector.

The power control system 30 controls the discharge of FC4 and the charge / discharge of BAT8. The power control system 30 includes a fuel cell DC / DC converter (hereinafter referred to as FDC) 32, a battery DC / DC converter (hereinafter referred to as BDC) 34, a motor inverter (hereinafter referred to as MINV) 38, and an auxiliary inverter (hereinafter referred to as MINV). Hereinafter referred to as AINV) 39 is included. The FDC 32 controls the output current by the FC4 based on the required current value transmitted from the ECU 3, adjusts the DC power from the FC4, and outputs the DC power to the MINV 38 or AINV 39. The BDC 34 adjusts the DC power from the BAT 8 and outputs it to the MINV 38 or AINV 39. The generated power of FC4 can be charged to BAT8. The MINV 38 converts the input DC power into three-phase AC power and supplies it to the motor 50. The motor 50 drives the wheels 5 to drive the vehicle. The electric power of FC4 and BAT8 can be supplied to a load device other than the motor 50 via AINV39. Here, the load device includes an auxiliary machine for FC4 and an auxiliary machine for a vehicle. The auxiliary equipment for FC4 includes the above-mentioned air compressor 14, three-way valve 15, back pressure valve 17, tank valve 24, pressure regulating valve 25, INJ26, drain valve 28, and HP29. Auxiliary equipment for vehicles includes, for example, air conditioning equipment, lighting equipment, hazard lamps, and the like. In addition, FC4 or BAT8 may be directly connected to MINV38 without providing BDC34 or FDC32.

The ECU 3 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The ECU 3 includes an ignition switch 2, an accelerator opening sensor 6, a stop standby switch 7, a navigation device 9, an air compressor 14, a three-way valve 15, a back pressure valve 17, a tank valve 24, a pressure regulating valve 25, INJ26, a drain valve 28, and HP29. The FDC 32 and the BDC 34 are electrically connected.

The ECU 3 starts and stops the vehicle 1 according to the on / off state of the ignition switch 2. The ECU 3 calculates the required output to the FC4 based on the detection value of the accelerator opening sensor 6, the driving state of the auxiliary equipment for the vehicle and the auxiliary equipment for the FC4 described above, the stored power of the BAT8, and the like, and this required output. The required current value for FC4 is calculated based on. Further, the ECU 3 controls the air compressor 14, INJ26, and HP29 according to the required output to the FC4 to control the flow rates of the cathode gas and the anode gas supplied to the FC4, and based on the required current value of the FC4. The output current of FC4 is controlled by controlling FDC32. The ECU 3 is an example of a control device that controls the FC4, the air compressor 14, the INJ26, and the HP29. Further, it is an example of a supply device for supplying the reaction gas to FC4 by supplying the air compressor 14, INJ26, and HP29 to FC4.

The stop standby switch 7 is a switch that can be manually operated, and by turning it on when it is not desired to completely stop the supply of the reaction gas to the FC4 when the power generation of the FC4 is stopped, the reaction gas to the FC4 can be turned on. The supply can be continued. For example, when the vehicle 1 is a delivery truck, it is often the case that the vehicle 1 is temporarily stopped at each store or each house when the cargo is loaded and unloaded, and then the vehicle 1 is restarted. In such a case, the power generation of the FC4 and the stop and restart of the supply of the reaction gas are repeated in a short period of time, the chance of the potential of the FC4 fluctuating greatly increases, and the power generation performance of the FC4 may deteriorate.

In such a case, if the stop standby switch 7 is in the ON state, the supply of the reaction gas to the FC4 is continued even if the power generation of the FC4 is stopped. As a result, the potential of FC4 is maintained high even when the power generation of FC4 is stopped, and the fluctuation of the potential is suppressed. As a result, deterioration of the power generation performance of FC4 can be suppressed. Further, by restarting the power generation while the potential of the FC4 is high, it is possible to output a high power immediately after the start of the power generation, and the responsiveness to the required output of the FC4 is improved.

Further, since the vehicle 1 is often stopped for a long time after the delivery is completed, the driver turns off the stop standby switch 7 to stop the power generation of the FC4 and the supply of the reaction gas. As a result, fuel consumption and power consumption due to the continuous supply of the reaction gas for a long time can be suppressed. Therefore, it is desirable that the driver turns on the stop standby switch 7 when starting delivery from the distribution base, and turns on the stop standby switch 7 when returning to the distribution base after the delivery is completed.

Here, it is conceivable that the driver forgets to switch the stop standby switch 7 from on to off after the delivery is completed. As a result, the supply of the reaction gas to FC4 is continued, and fuel and electric power are wasted accordingly. For example, in an engine vehicle, when the engine is stopped, the vibration and noise of the engine up to that point are also stopped, so that the driver can easily grasp the stop of the engine and rarely forget the above operation. However, in the case of the fuel cell vehicle 1, there is a concern that the above operation may be forgotten because the change in vibration and noise is small even if the power generation of the FC4 is stopped. Therefore, even if the stop / standby switch 7 is on, the ECU 3 switches the stop / standby switch 7 to off and stops the supply of the reaction gas when a predetermined condition is satisfied. The control executed by the ECU 3 will be described below.

FIG. 2 is a flowchart showing an example of the control executed by the ECU 3. This control is repeatedly executed. The ECU 3 determines whether or not there is a request to stop the power generation of the FC 4 (step S1). For example, when the ignition switch 2 is switched from on to off, the FC4 is requested to stop power generation. If No in step S1, this control ends. If Yes in step S1, the ECU 3 stops the power generation of FC4 (step S2). Specifically, the ECU 3 controls the FDC 32 to reduce the sweep current to the FC 4 to zero, thereby stopping the power generation of the FC 4. If the FDC 32 is provided with a switch that can switch between electrical connection and disconnection with the FC 4, the ECU 3 controls this switch to disconnect the FC 4 and the FDC 32 to generate electricity from the FC 4. You may stop.

Next, the ECU 3 determines whether or not the stop standby switch 7 is on (step S3). If No in step S3, the ECU 3 stops the air compressor 14, INJ26, and 29, and stops the supply of the reaction gas to FC4 (step S8).

If Yes in step S3, the ECU 3 determines whether or not there is a power generation restart request for FC4 (step S4). For example, when the ignition switch 2 is switched from off to on, the FC4 is requested to restart power generation. If Yes in step S4, the ECU 3 restarts the power generation of FC4 (step S5). Specifically, the ECU 3 controls the FDC 32 to make the sweep current to the FC 4 a value larger than zero, thereby restarting the power generation of the FC 4. If the FDC 32 is provided with a switch that can switch between electrical connection and disconnection with the FC 4, the ECU 3 needs to control this switch to connect the FC 4 and the FDC 32.

If No in step S4, the ECU 3 determines whether or not the vehicle 1 is stopped at a predetermined position (step S6). The predetermined position is a base position of the vehicle 1 registered in advance, and for example, when the vehicle 1 is a delivery truck, it is a distribution center. The navigation device 9 has a built-in GPS (Global Positioning System) receiver that acquires the position information of the vehicle 1, and the ECU 3 acquires the stop position of the vehicle from the navigation device 9. The navigation device is an example of an acquisition device. If No in step S6, the process of step S4 is executed again. In the case of Yes in step S6, the ECU 3 switches the stop standby switch 7 off (step S7) and stops the supply of the reaction gas to the FC4 (step S8).

That is, when the vehicle 1 is stopped at a position other than the predetermined position, it is unlikely that the vehicle will be stopped for a long time, and the supply of the reaction gas to the FC4 is continued and the vehicle 1 is stopped at the predetermined position. The stop standby switch 7 is switched off (step S7), and the supply of the reaction gas is stopped (step S8), assuming that the vehicle is likely to be stopped for a long time.

The control of supplying the reaction gas to the FC4 whose power generation has stopped is also referred to as intermittent operation. In the intermittent operation, for example, the drive of the air compressor 14, INJ26, and HP29 is controlled so that the open circuit voltage of FC4 is maintained within a predetermined target range. This "driving" includes not only continuously driving the air compressor 14 and the like without providing a pause period, but also intermittent drive that repeats temporary pause and drive. Therefore, for example, when the open circuit voltage falls below the lower limit of the target range, the air compressor 14 may be driven to supply the cathode gas to the FC4, and when the open circuit voltage exceeds the upper limit of the target range, the air compressor 14 may be stopped.

In the above embodiment, when the stop standby switch 7 is on and the stop position is other than the predetermined position when there is a power generation stop request, the power generation of the FC4 is stopped and the supply of the reaction gas is continued. The supply of the reaction gas may be continued while continuing the power generation of the FC4 without limitation. In this case, it is considered that the stop time is short, and there is no problem even if the power generation of FC4 is continued. In this case, it is desirable that the process of stopping the power generation in step S2 described above is executed together with step S8 or immediately before or after step S8, not between steps S1 and S3.

In the above embodiment, the ECU 3 acquires the stop position of the vehicle 1 from the navigation device 9, but the present invention is not limited to this, and may be acquired directly from, for example, a GPS logger mounted on the vehicle, or may be managed by a distribution center, for example. The server that recorded such location information may be obtained via a wireless communication line.

Although the examples of the present invention have been described in detail above, the present invention is not limited to such specific examples, and various modifications and modifications are made within the scope of the gist of the present invention described in the claims. It can be changed.

3 ECU (control device)
7 Stop standby switch (switch)
14 Air compressor (supply device)
26 Injector (supply device)
29 Hydrogen circulation pump (supply device)

Claims (1)

With a fuel cell
A supply device that supplies reaction gas to the fuel cell,
A switch that can be operated manually and
An acquisition device that acquires stop position information,
In a fuel cell vehicle provided with a power generation state of the fuel cell and a control device for controlling the supply device.
When there is a request to stop the power generation of the fuel cell, the control device stops the power generation of the fuel cell and stops the supply device when the switch is off, and the switch is on and the vehicle is stopped. When the position is other than the predetermined position, the power generation of the fuel cell is continued or stopped to continue driving the supply device, and when the switch is on and the stop position is the predetermined position, the fuel cell A fuel cell vehicle that stops power generation and switches off the switch to stop the supply device.

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