Fuel cell vehicles

Abstract

The present disclosure relates to a fuel cell vehicle. The FCV (1) includes a FC system (20) and a battery (40). The FC system (20) includes a FC stack (22) and a boost converter (24) for adjusting the output of the FC stack (22). The FDC-ECU (60) controls the boost converter (24) so ​​that when the SOC of the battery (40) is lower than a threshold value (S1) when the system of the FCV (1) is stopped (ready-off), when a prescribed operation for external charging by a power source outside the vehicle is not performed for a prescribed time after the system is stopped, FC charging is performed by the FC system (20).

Description

Technical Field

[0001] The present disclosure relates to a fuel cell vehicle. Background Art

[0002] International Publication No. 2011 / 004493 discloses a fuel cell vehicle equipped with a fuel cell (hereinafter, the fuel cell is referred to as "FC (Fuel Cell)" and the fuel cell vehicle is referred to as "FCV (Fuel Cell Vehicle)"). The FCV has an FC stack and a battery. The battery functions as a storage source for surplus power, a storage source for regenerative energy during regenerative braking, and an energy buffer for load fluctuations associated with acceleration or deceleration of the vehicle.

[0003] A so-called plug-in FCV is being studied that can charge a power storage device by a power supply outside the vehicle (hereinafter, the power supply outside the vehicle is also referred to as an "external power supply", and charging of the power storage device by the external power supply is also referred to as "external charging"). However, if external charging is not performed after the system of the FCV is stopped and the state of charge (SOC: State Of Charge) of the power storage device decreases when the system is started, the system output obtained by adding the output of the FC and the output of the power storage device is limited after the start of driving, and the driving performance may be reduced. Summary of the invention

[0004] The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to suppress a decrease in driving performance after a system startup of the FCV in an FCV including an FC and a power storage device.

[0005] The FCV disclosed in the present invention comprises: an FC system; a power storage device; a drive device that receives power from at least one of the FC system and the power storage device to generate driving power; a charging device that performs external charging; and a control device. The output upper limit of the power storage device is set so that when the SOC is lower than a threshold value, the output upper limit of the power storage device decreases as the SOC decreases. The control device controls the FC system so that when the SOC is lower than the threshold value when the system of the FCV is stopped, FC charging is performed to supply power from the FC system to the power storage device when external charging is not performed.

[0006] When the SOC decreases and falls below the threshold, the system output is limited due to the decrease in the output upper limit of the power storage device. The FCV is equipped with a charging device for external charging, and the SOC at the time of system startup can be increased in advance by performing external charging during system stop. However, if there is no charging equipment in the parking lot or the user forgets external charging, external charging may not be performed during system stop.

[0007] In this FCV, when the SOC is lower than the threshold value when the system is stopped, FC charging is performed when external charging is not performed. Therefore, even when external charging is not performed when the system is stopped, the SOC can be increased in advance at the next system start, and the system output can be avoided from being limited at the start of driving after the system is started. Therefore, according to this FCV, it is possible to suppress the reduction of driving performance after the system is started.

[0008] The control device may control the FC system so that, when the SOC is lower than a threshold value when the system is stopped, FC charging is performed when a predetermined operation for external charging has not been performed for a predetermined time after the system is stopped.

[0009] In this FCV, when the operation for external charging is not performed for a predetermined time after the system is stopped, it is determined that external charging is not performed, and if the SOC is lower than a threshold value when the system is stopped, FC charging is performed. Therefore, according to this FCV, even if external charging is not performed when the system is stopped, the SOC can be increased in advance at the next system start, and the system output can be avoided from being limited at the system start.

[0010] When the above-described operation is performed during execution of FC charging, the control device may stop FC charging and execute external charging.

[0011] According to this FCV, when external charging is requested even during FC charging, FC charging is stopped and external charging is performed, so that a decrease in the remaining fuel amount at the time of system startup can be suppressed.

[0012] The control device may control the FC system so that when the above-mentioned operation is performed, if the electricity charge due to external charging is higher than a predetermined amount, external charging is not performed but FC charging is performed.

[0013] According to this FCV, when the electricity rate for external charging is high, FC charging is performed even when external charging is requested, so that the energy cost for suppressing the reduction in the running performance after the system startup can be controlled.

[0014] The control device may control the FC system so that FC charging is performed when the SOC is lower than a threshold value at system startup of the FCV.

[0015] In this FCV, when the SOC is lower than the threshold value at system startup, FC charging is performed, so that the system output can be prevented from being limited due to a decrease in SOC. Therefore, according to this FCV, it is possible to suppress a decrease in driving performance after system startup.

[0016] In addition, the FCV of the present disclosure includes: an FC system; a power storage device; a drive device that receives power from at least one of the FC system and the power storage device to generate driving power; a charging device that performs external charging; a display device that can be operated by a user of the FCV; and a control device. The output upper limit of the power storage device is set so that when the SOC is lower than a threshold value, the output upper limit of the power storage device decreases as the SOC decreases. When the SOC is lower than the threshold value when the system of the FCV is stopped, the control device displays an operation unit for the user to instruct the execution of FC charging on the display device.

[0017] In this FCV, when the SOC is lower than a threshold value during system stop, an operation unit for the user to instruct execution of FC charging is displayed on the display device. Thus, even when external charging is not performed during system stop, by executing FC charging during system stop in accordance with the user's instruction, the SOC can be improved in advance at the next system start. Therefore, according to this FCV, it is possible to avoid the system output being limited during system start, and as a result, it is possible to suppress the reduction in driving performance after the system start.

[0018] The foregoing and other objects, features, aspects and advantages of the present disclosure will become apparent from the following detailed description when read in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 : is a figure which shows the whole structure of the FCV according to the embodiment of this disclosure.

[0020] Figure 2 This is a diagram showing the travel modes provided in the FCV.

[0021] Figure 3 : is a diagram showing the relationship between the remaining energy of the FC system and the battery and the upper limit of the system output.

[0022] Figure 4 This is a flowchart showing an example of a process procedure executed by the FDC-ECU at the time of Ready-off.

[0023] Figure 5 This is a flowchart showing an example of a procedure of a process executed by the FDC-ECU at the time of Ready-off in Modification 1.

[0024] Figure 6 This is a flowchart showing an example of a procedure of a process executed by the FDC-ECU at the time of Ready-off in Modification 2.

[0025] Figure 7 This is a flowchart showing an example of a procedure of a process executed by the FDC-ECU at the time of Ready-off in the second embodiment.

[0026] Figure 8 Yes means Figure 7 FIG. 5 is a diagram showing an example of a display state of the HMI device in step S330 .

[0027] Fig. 9 This is a flowchart showing an example of a procedure of a process executed by the FDC-ECU at the time of Ready-on in the third embodiment. DETAILED DESCRIPTION

[0028] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. It should be noted that the same reference numerals are given to the same or corresponding parts in the drawings, and their description will not be repeated.

[0029] [Implementation Method 1]

[0030] Figure 1 1 is a diagram showing the overall structure of an FCV 1 according to an embodiment of the present disclosure. Figure 1 The FCV 1 includes a motor generator (hereinafter referred to as “MG (Motor Generator)”) 10 , an inverter 12 , an FC system 20 , a hydrogen tank 28 , a supply valve 30 , an air filter 32 , and a compressor 34 .

[0031] MG10 is an AC rotating electric machine, for example, a three-phase AC synchronous motor with a permanent magnet embedded in the rotor. MG10 is driven by the inverter 12 to generate a rotational driving force. The driving force generated by MG10 is transmitted to a driving wheel not shown. When the FCV1 is braked, MG10 operates as a generator to generate electricity. The electric power generated by MG10 is rectified by the inverter 12 and stored in the battery 40.

[0032] Inverter 12 is provided between power line 70 and MG 10, and drives MG 10 based on a drive signal from MG-ECU 66 (described later). Inverter 12 is formed of, for example, a bridge circuit including three-phase switching elements.

[0033] The FC system 20 includes an FC stack 22, a boost converter 24, and a relay 26. The FC stack 22 is, for example, a structure in which a plurality (e.g., tens to hundreds) of solid polymer-type single cells are stacked in series. Each single cell is, for example, formed by bonding catalyst electrodes to both sides of an electrolyte membrane and sandwiching the electrolyte membrane between conductive separators, and hydrogen supplied to the anode and oxygen (air) supplied to the cathode undergo an electrochemical reaction to generate electricity.

[0034] The boost converter 24 boosts the power generated by the FC stack 22 (for example, several hundred volts) based on a control signal from the FDC-ECU 60 (described later) and outputs it to the power line 70. The relay 26 is provided in the circuit between the FC stack 22 and the boost converter 24, and is disconnected when the vehicle system is stopped and the FC system 20 is not in use.

[0035] The hydrogen tank 28 stores fuel hydrogen supplied to the FC stack 22. The hydrogen tank 28 is a lightweight, high-strength high-pressure tank including a carbon fiber reinforced plastic layer, for example, and can store hydrogen at, for example, several tens of MPa. Hydrogen is supplied from the hydrogen tank 28 to the FC stack 22 via a supply valve 30.

[0036] The compressor 34 is a device for supplying oxygen to the FC stack 22. The compressor 34 sucks oxygen (air) through the air filter 32, compresses the air, and supplies the air to the FC stack 22.

[0037] The FCV 1 further includes a battery 40 , a DC (Direct Current) inlet 44 , an AC (Alternate Current) inlet 48 , a charger 50 , and relays 42 , 46 , and 52 .

[0038] The battery 40 is a storage device configured to be chargeable and dischargeable. The battery 40 includes a battery pack composed of a plurality of battery cells (e.g., several hundred cells). Each battery cell is, for example, a secondary battery such as a lithium-ion battery or a nickel-metal hydride battery. It should be noted that a lithium-ion secondary battery is a secondary battery that uses lithium as a charge carrier, and in addition to a general lithium-ion secondary battery in which the electrolyte is a liquid, it can also include a so-called all-solid-state battery that uses a solid electrolyte. Instead of the battery 40, a storage element such as a double-layer capacitor can also be used.

[0039] The battery 40 is connected to the power line 72 via the relay 42, and the power line 72 is connected to the power line 70. The battery 40 stores power for driving the MG 10, and supplies power to the inverter 12 through the power lines 72 and 70. In addition, the battery 40 is charged by receiving power generated by the MG 10 when the FCV 1 is braked, etc. The battery 40 can function as an energy buffer that absorbs load fluctuations associated with the acceleration and deceleration of the FCV 1, or stores power generated by the MG 10 when the FCV 1 is braked, etc.

[0040] In addition, in the present embodiment, the battery 40 can be charged (external charging) by receiving power supplied from a power source (not shown) outside the vehicle through the DC inlet 44 or the AC inlet 48. Furthermore, the battery 40 can also be charged by receiving power output from the FC system 20 (hereinafter, charging of the battery 40 by the FC system 20 is also referred to as "FC charging").

[0041] DC inlet 44 is connected to power line 74 via relay 46, and power line 74 is connected to power line 72. DC inlet 44 is configured as a connector capable of fitting a DC charging cable extending from a charging station or the like outside the vehicle (not shown), receives high-voltage DC power supplied from the charging station or the like, and outputs it to power line 74.

[0042] AC inlet 48 is connected to charger 50 via relay 52. ​​AC inlet 48 is configured to be able to be fitted with a connector of an AC charging cable extending from a charging station or the like outside the vehicle, receives AC power (e.g., system power) supplied from the charging station or the like, and outputs it to charger 50. Charger 50 is connected to power line 74, converts the AC power input from AC inlet 48 into a voltage level of battery 40, and outputs it to power line 74.

[0043] Relay 42 is provided between battery 40 and power line 72, and is closed during system startup of FCV 1 or execution of external charging. Relay 46 is provided between DC inlet 44 and power line 74, and is closed during execution of external charging (DC charging) using DC inlet 44. Relay 52 is provided between AC inlet 48 and charger 50, and is closed during execution of external charging (AC charging) using AC inlet 48 and charger 50.

[0044] As described above, the FCV 1 is a plug-in FCV in which the battery 40 can be charged by a power source external to the vehicle connected to the DC inlet 44 or the AC inlet 48 , and can travel using the electric power stored in the battery 40 by external charging.

[0045] FCV1 also includes FDC-ECU (Electronic Control Unit) 60, mode switch (MD-SW) 62, battery ECU 64, MG-ECU 66, HMI (Human Machine Interface) device 68. FDC-ECU 60, battery ECU 64 and MG-ECU 66 are respectively configured to include CPU (Central Processing Unit), memory (ROM (Read Only Memory) and RAM (Random Access Memory)) and input / output buffer (none of which are shown in the figure). CPU expands and executes the program stored in ROM in RAM, etc. The program stored in ROM describes the processing to be executed by the corresponding ECU.

[0046] The FDC-ECU 60 calculates the output requested from the FC system 20 (the output power of the FC system 20) based on the running power requested from the FCV 1 and the charge / discharge request from the battery 40, and controls the boost converter 24 so that the FC system 20 outputs the calculated power. It should be noted that the running power requested from the FCV 1 is calculated based on the operation amount of the accelerator pedal and the vehicle speed, etc. In the present embodiment, the running power is calculated by the FDC-ECU 60, but it may also be calculated by other ECUs (for example, a vehicle ECU (not shown) that controls the entire vehicle as a whole).

[0047] The FDC-ECU 60 controls the output of the FC system 20 so that the output of the FC system 20 does not exceed the output upper limit Wfc and the output of the battery 40 does not exceed the output upper limit Wout. It should be noted that in the present embodiment, the output upper limit Wfc of the FC system 20 is set by the FDC-ECU 60, and the output upper limit Wout of the battery 40 is set by the battery ECU 64 based on the SOC and temperature of the battery 40. The output upper limit Wfc of the FC system 20 and the output upper limit Wout of the battery 40 will be described in detail later.

[0048] In addition, the FDC-ECU 60 switches the driving mode according to the setting made by the mode switch 62. The FCV 1 is equipped with the FC system 20 and the battery 40 as power sources, and electric power can be stored in the battery 40. In addition, the FCV 1 has four driving modes corresponding to the use methods of the FC system 20 and the battery 40, and the user can select the driving mode by operating the mode switch 62. The driving mode will be described in detail later.

[0049] The mode switch 62 is a switch for the user to set the driving mode. The mode switch 62 may be a dedicated switch or may be formed in the touch panel display of the HMI device 68.

[0050] The HMI device 68 is a device that provides various information to the user of the FCV 1 or accepts operations by the user of the FCV 1. The HMI device 68 includes a display including a touch panel, a speaker, and the like.

[0051] The battery ECU 64 monitors the voltage, current, temperature, etc. of the battery 40. The voltage, current, temperature, etc. of the battery 40 are detected by various sensors not shown. In addition, the battery ECU 64 calculates the SOC of the battery 40 based on the detected values ​​of the voltage, current, temperature, etc. of the battery 40. The calculated SOC value is sent to the FDC-ECU 60. It should be noted that the calculation of the SOC can also be performed by the FDC-ECU 60 based on the detected values ​​of the voltage, current, temperature, etc. of the battery 40.

[0052] Furthermore, the battery ECU 64 sets an output upper limit Wout of the battery 40 . Specifically, the battery ECU 64 sets the output upper limit Wout so that when the SOC of the battery 40 is lower than a threshold value, the output upper limit Wout decreases as the SOC decreases. The battery ECU 64 then sends the set output upper limit Wout to the FDC-ECU 60 .

[0053] In the FCV 1, the battery 40 is connected to the power line 70 without a converter, and basically, the charge and discharge amount of the battery 40 depends on the difference between the running power requested by the inverter 12 and the MG 10 and the output of the FC system 20. Therefore, by controlling the output of the FC system 20 based on the running power by the FDC-ECU 60, the charge and discharge of the battery 40 and the SOC can be controlled.

[0054] In the FCV 1, a target SOC indicating a target SOC is set by the FDC-ECU 60 according to the running mode. The charge / discharge request amount of the battery 40 is calculated based on the deviation between the SOC and the target SOC so that the SOC of the battery 40 approaches the target SOC, and the output of the FC system 20 is controlled by the FDC-ECU 60 based on the calculated charge / discharge request amount and the running power.

[0055] The target SOC will be described in detail later. It should be noted that various known methods can be used to calculate the SOC, such as a method using an OCV-SOC curve (mapping diagram, etc.) that represents the relationship between OCV (Open Circuit Voltage) and SOC, a method using the cumulative value of the current input and output relative to the battery 40, etc.

[0056] The MG-ECU 66 receives the calculated value of the running power requested to the FCV 1 from the FDC-ECU 60 , generates a signal for driving the MG 10 via the inverter 12 based on the running power, and outputs the signal to the inverter 12 .

[0057] <Explanation of driving modes>

[0058] As described above, the FCV 1 includes the FC system 20 and the battery 40. In addition, in the present embodiment, four travel modes corresponding to the method of using the FC system 20 and the battery 40 are provided.

[0059] Figure 2 2 is a diagram showing the driving mode provided in the FCV 1. Figure 2 In the present embodiment, there are four driving modes, namely, “FC mode”, “FCEV mode”, “EV mode”, and “CHG mode”. The user of the FCV 1 can select a desired driving mode from among these driving modes using the mode switch 62 .

[0060] The FC mode is a running mode in which the vehicle is basically driven only by the output of the FC system 20 until the fuel (hydrogen) of the FC system 20 is exhausted. After the fuel is exhausted, the vehicle is driven only by the output of the battery 40.

[0061] In the FC mode, in order to travel using only the output of the FC system 20 , the FDC-ECU 60 controls the FC system 20 (boost converter 24 ) based on the traveling power so that the FC system 20 outputs power equivalent to the traveling power (request value) required by the inverter 12 .

[0062] It should be noted that even in the FC mode, when the accelerator pedal is greatly depressed to request a large running power, and the running power exceeds the output upper limit Wfc of the FC system 20, the shortfall in power is supplied from the battery 40. Furthermore, when the MG 10 performs regenerative power generation during braking of the FCV 1, the power generated by the MG 10 is supplied from the inverter 12 to the battery 40.

[0063] The FCEV mode is a hybrid mode that uses the output of the FC system 20 and the output of the battery 40 in a balanced manner. As an example, in the FCEV mode, the vehicle is driven in accordance with the requested driving power and the SOC is maintained at the target SOC, using both the output of the FC system 20 and the output of the battery 40. Specifically, the FDC-ECU 60 controls the FC system 20 (boost converter 24) based on the driving power and the SOC of the battery 40 so that the input and output of the battery 40 are adjusted so that the SOC is maintained at the target SOC and the power required by the inverter 12, that is, the driving power (request value) is supplied.

[0064] It should be noted that even in the FCEV mode, when the accelerator pedal is greatly depressed to request a large running power, and the running power exceeds the output upper limit of the FC system 20, power corresponding to the difference between the SOC and the target SOC is supplied from the battery 40. In addition, when the MG 10 performs regenerative power generation during braking of the FCV 1, the power generated by the MG 10 is supplied from the inverter 12 to the battery 40.

[0065] The EV mode is a running mode in which the vehicle runs basically only using the output of the battery 40 without using the fuel (hydrogen) of the FC system 20 .

[0066] It should be noted that even in the EV mode, when the accelerator pedal is depressed greatly to request a large running power, and the running power exceeds the output upper limit Wout of the battery 40, the insufficient power can be output from the FC system 20. In addition, when the MG 10 performs regenerative power generation during braking of the FCV 1, the power generated by the MG 10 is supplied from the inverter 12 to the battery 40.

[0067] The CHG mode is a mode in which, when the SOC of the battery 40 is reduced, the battery 40 is actively charged using the output of the FC system 20 to increase the SOC to a predetermined level.

[0068] It should be noted that even in the CHG mode, if the accelerator pedal is stepped on and the running power is requested, the power is supplied from the FC system 20 to the inverter 12. Furthermore, when the accelerator pedal is stepped on heavily and a large running power is requested, the power is supplied from the battery 40 to the inverter 12. Furthermore, when the MG 10 performs regenerative power generation during braking of the FCV 1, the power generated by the MG 10 is supplied from the inverter 12 to the battery 40.

[0069] In the FCV 1, as described above, the battery 40 can be charged by a power source outside the vehicle (external charging). However, if external charging is not performed after the system of the FCV 1 is stopped (after Ready-off) and the SOC of the battery 40 is reduced when the system is started (at Ready-on), the system output obtained by adding the output of the FC system 20 and the output of the battery 40 is limited after the start of traveling, and the traveling performance may be reduced.

[0070] Figure 3 is a diagram showing the relationship between the remaining energy of the FC system 20 and the battery 40 and the upper limit of the system output. Figure 3 , the horizontal axis represents the energy remaining amount (%) of the FC system 20 and the battery 40, respectively, and the vertical axis represents the system output upper limit (W) obtained by adding the output upper limit of the FC system 20 to the output upper limit of the battery 40. It should be noted that the energy remaining amount on the horizontal axis represents the hydrogen remaining amount (100% is a fully filled state) for the FC system 20, and represents the SOC for the battery 40.

[0071] Reference Figure 3, the output upper limit Wfc of the FC system 20 is a constant value regardless of the remaining amount of hydrogen. That is, the FC system 20 can output power to the output upper limit Wfc regardless of the remaining amount of hydrogen until the fuel is exhausted. On the other hand, when the SOC is lower than the threshold value S1, the output upper limit Wout of the battery 40 decreases as the SOC decreases. Therefore, when the SOC in the battery 40 is lower than the threshold value S1, the system output upper limit obtained by adding the output upper limit Wfc of the FC system 20 to the output upper limit Wout of the battery 40 decreases as the SOC decreases. And, when the system output upper limit decreases, the driving power during acceleration is limited, thereby reducing the driving performance.

[0072] Therefore, in the FCV 1 according to the first embodiment, when the SOC is lower than the threshold value S1 at the time of Ready-off, if external charging by the external power source is not being performed, the CHG mode is automatically selected. More specifically, when the SOC is lower than the threshold value S1 at the time of Ready-off, if the connection between the charging cable and the DC inlet 44 or the AC inlet 48 is not performed for a predetermined time after Ready-off, it is determined that external charging is not being performed, and FC charging by the FC system 20 is performed.

[0073] Thus, even when external charging is not performed during system stop of FCV1, the SOC can be increased in advance at the next Ready-on, and the system output can be prevented from being limited at the start of travel after Ready-on. Therefore, the travel performance can be suppressed from being reduced after Ready-on.

[0074] Figure 4 This is a flowchart showing an example of the process procedure executed by FDC-ECU 60 at the time of Ready-off. It should be noted that part of the process may be shared by battery ECU 64 or MG-ECU 66, or may be performed by other ECUs (such as a vehicle ECU that controls the entire vehicle as a whole) not shown.

[0075] Reference Figure 4 When a start switch (not shown) is operated and Ready-off (FCV1 system stop) is requested (Yes in step S10), the FDC-ECU 60 obtains the SOC of the battery 40 from the battery ECU 64 and determines whether the SOC is lower than a threshold value S1 ( Figure 3 ) (Step S20 ). If the SOC is equal to or higher than the threshold value S1 (No in Step S20 ), the subsequent series of processes are not executed and the process is terminated.

[0076] When it is determined in step S20 that the SOC is lower than threshold value S1 (YES in step S20), FDC-ECU 60 determines whether a predetermined operation for external charging has been performed (step S30). The predetermined operation is, for example, an operation of connecting the connector of the charging cable to DC inlet 44 or AC inlet 48. When the connection between DC inlet 44 or AC inlet 48 and the connector of the charging cable is sensed, it is determined that the above operation has been performed.

[0077] When it is determined that the operation has not been performed (No in step S30), FDC-ECU 60 determines whether a predetermined time has passed (step S50), and if the predetermined time has not passed (No in step S50), the process returns to step S30. That is, in steps S30 and S50, it is determined whether the operation for external charging after Ready-off is performed within the predetermined time.

[0078] When it is determined in step S30 that an operation for external charging has been performed (within a predetermined time after Ready-off) (YES in step S30), external charging of battery 40 by an external power source connected to DC inlet 44 or AC inlet 48 is performed (step S40). Specifically, when the connector of the DC charging cable is connected to DC inlet 44, relays 42 and 46 are closed, and battery 40 is charged by the DC charging device connected to DC inlet 44. On the other hand, when the connector of the AC charging cable is connected to AC inlet 48, relays 42 and 52 are closed and charger 50 is driven, and battery 40 is charged by the AC charging device connected to AC inlet 48.

[0079] When it is determined in step S50 that the predetermined time has passed (YES in step S50), FDC-ECU 60 determines that external charging is not being performed, and selects the CHG mode to perform FC charging of the battery 40 by the FC system 20 (step S60). Specifically, FDC-ECU 60 sets the target SOC of the battery 40 to S2 which is higher than the threshold value S1, and drives the boost converter 24 of the FC system 20 so that power is supplied from the FC system 20 to the battery 40.

[0080] During FC charging, FDC-ECU 60 determines whether SOC of battery 40 exceeds S2 (S2>threshold S1) (step S70). If SOC increases due to FC charging and it is determined that SOC exceeds S2 (YES in step S70), FDC-ECU 60 terminates FC charging and moves the process to end.

[0081] As described above, in the first embodiment, when the SOC is lower than the threshold value S1 at the time of Ready-off, if the operation for external charging is not performed for a predetermined time after Ready-off, the FC system 20 is driven to perform FC charging. Thus, even if external charging is not performed during system stop, the SOC can be increased in advance at the next Ready-on, and the system output can be prevented from being limited at the start of travel after Ready-on. Therefore, according to the first embodiment, it is possible to suppress the reduction of travel performance after Ready-on.

[0082] [Modification 1]

[0083] Alternatively, when FC charging is started without external charging even though the SOC is lower than the threshold value S1 at the time of Ready-off, if an operation for external charging is performed during FC charging, FC charging is stopped and external charging is performed. In this way, when external charging is requested during FC charging, a decrease in the remaining fuel amount can be suppressed by switching from FC charging to external charging.

[0084] Figure 5 1 is a flowchart showing an example of a process procedure executed by the FDC-ECU 60 at the time of Ready-off in the first modification. This flowchart is similar to the flowchart described in the first embodiment. Figure 4 The corresponding flow chart.

[0085] Reference Figure 5 The processing of steps S110 to S170 is respectively Figure 4 The processes of steps S10 to S70 are the same, and thus will not be described repeatedly. In the first modification, when FC charging is performed in step S160, the FDC-ECU 60 determines whether a predetermined operation for external charging is performed during the execution of FC charging (step S162).

[0086] When it is determined that the operation is not being performed (NO in step S162 ), FDC-ECU 60 shifts the process to step S170 to determine whether the SOC of battery 40 is higher than S2 ( S2 > threshold value S1 ).

[0087] On the other hand, when it is determined in step S162 that an operation for external charging is performed during FC charging (YES in step S162 ), FDC-ECU 60 stops FC charging (step S164 ). Specifically, FDC-ECU 60 stops driving boost converter 24 of FC system 20 .

[0088] Then, when FC charging is stopped, FDC-ECU 60 shifts the process to step S140 , and executes external charging by the external power supply connected to DC inlet 44 or AC inlet 48 .

[0089] As described above, according to the first modification, when external charging is requested even during FC charging, FC charging is stopped and external charging is performed, so that a decrease in the remaining fuel amount at the time of Ready-on can be suppressed.

[0090] [Modification 2]

[0091] Even when the SOC is lower than the threshold value S1 at the time of Ready-off and an operation for external charging is performed, if it is determined that the electricity cost of external charging is relatively expensive and the electricity cost of external charging is higher than the cost of fuel, FC charging is performed instead of external charging. In this way, the energy cost (charging cost) for suppressing the reduction in driving performance after Ready-on can be controlled.

[0092] Figure 6 1 is a flowchart showing an example of a process procedure executed by the FDC-ECU 60 at the time of Ready-off in the second modification. This flowchart is also similar to that described in the first embodiment. Figure 4 The corresponding flow chart.

[0093] Reference Figure 6 The processing of steps S210 to S270 is respectively Figure 4 The processing of steps S10 to S70 is the same, so the description is not repeated. In addition, in this modification 2, when it is determined in step S230 that the operation for external charging is performed (yes in step S230), the FDC-ECU 60 obtains the unit price of the electricity fee when performing external charging from the server of the power company, etc., and determines whether the electricity fee generated by the external charging is higher than the specified amount (step S232).

[0094] For example, the FDC-ECU 60 calculates the amount of electricity charged until the SOC reaches S2, and when the electricity cost when the amount of electricity is replenished by external charging is higher than the fuel cost when the amount of electricity is replenished by FC charging, it is determined that the electricity cost generated by external charging is higher than the prescribed amount. It should be noted that the electricity cost generated by external charging can be calculated by multiplying the unit price of the acquired electricity cost by the amount of electricity charged. In addition, the fuel cost when replenished by FC charging can be calculated by pre-acquiring the relationship between the power generated by the FC system 20 and the fuel consumption and the unit price of fuel. Alternatively, it may be that when the unit price of the electricity cost when performing external charging is higher than the amount level that can distinguish the more expensive unit price of the daytime from the cheaper unit price of the late night, it is determined that the electricity cost generated by external charging is higher than the prescribed amount.

[0095] Then, when it is determined in step S232 that the electricity rate is higher than the predetermined amount (YES in step S232 ), FDC-ECU 60 shifts the process to step S260 to execute FC charging.

[0096] On the other hand, when it is determined in step S232 that the electricity fee is equal to or less than the predetermined amount (NO in step S232 ), FDC-ECU 60 shifts the process to step S240 to execute external charging.

[0097] As described above, according to the second modification, when the electricity rate for external charging is high, FC charging is performed even if external charging is requested, so that the energy cost for suppressing the reduction in the running performance after Ready-on can be controlled.

[0098] [Implementation Method 2]

[0099] In the first embodiment described above, FC charging is performed when external charging is not performed even though the SOC is lower than the threshold value S1 at the time of Ready-off, but in the second embodiment, when the SOC is lower than the threshold value S1 at the time of Ready-off, an operation button for the user to instruct the execution of FC charging is displayed on the HMI device 68. Thus, the user can directly permit FC charging, or, if the user simply forgets the operation for performing external charging, can perform external charging by performing the operation and not permitting FC charging.

[0100] The overall structure of the FCV according to the second embodiment and Figure 1 The FCV1 of the embodiment 1 shown is the same.

[0101] Figure 7 1 is a flowchart showing an example of a process procedure executed by the FDC-ECU 60 at the time of Ready-off in the second embodiment. This flowchart is similar to the flowchart described in the first embodiment. Figure 4 The corresponding flow chart.

[0102] Reference Figure 7 The processing of steps S310 and S320 is respectively the same as Figure 4 The processing of steps S10 and S20 is the same, so the description is not repeated. In the second embodiment, when it is determined in step S320 that the SOC is lower than the threshold value S1 ( Figure 3 ) (YES in step S320 ), FDC-ECU 60 displays a switch (operation button) for the user to select whether to permit execution of FC charging on HMI device 68 (step S330 ).

[0103] Figure 8 Yes means Figure 7 FIG. 6 is a diagram showing an example of the display state of the HMI device 68 in step S330. Figure 8 , a pop-up screen 80 is displayed on the touch panel display of the HMI device 68. The pop-up screen 80 displays, for example, a character string such as "The battery remaining amount is low. Is battery charging (FC charging) by hydrogen permitted?", and also displays an input unit 82 for indicating that FC charging is permitted and an input unit 84 for indicating that FC charging is not permitted. When the user touches the input unit 82, FC charging is permitted, and when the user touches the input unit 84, FC charging is not permitted.

[0104] Refer again Figure 7 , the FDC-ECU 60 determines whether FC charging is permitted by the user in the HMI device 68 (step S340). Then, if FC charging is permitted (yes in step S340), the FDC-ECU 60 moves the process to step S350 to execute FC charging. The processes of steps S350 and S360 are respectively similar to those of step S360. Figure 4 The processing of steps S60 and S70 is the same, so the description will not be repeated.

[0105] On the other hand, when FC charging is not permitted (NO in step S340), FDC-ECU 60 does not execute steps S350 and S360 but ends the process. Although not particularly shown, external charging is executed if an operation for external charging is subsequently performed.

[0106] As described above, in the second embodiment, when the SOC is lower than the threshold value S1 at the time of Ready-off, the operation button (input unit 82, 84) for the user to instruct the execution of FC charging is displayed on the HMI device 68. Thus, even when external charging is not performed during system stop, by executing FC charging during system stop in accordance with the user's instruction, the SOC can be improved in advance at the next Ready-on. Therefore, according to the second embodiment, it is possible to avoid the system output being limited at the time of Ready-on, and as a result, it is possible to suppress the deterioration of the driving performance after Ready-on.

[0107] [Implementation method 3]

[0108] In the first embodiment described above, when the SOC of the battery 40 is lower than the threshold value S1 in Ready-off, FC charging is performed when external charging is not performed. However, in the third embodiment, FC charging is performed when the SOC is lower than the threshold value S1 in Ready-on.

[0109] The overall configuration of the FCV according to the third embodiment is also similar to that according to the Figure 1 The FCV1 of the embodiment 1 shown is the same.

[0110] Fig. 9 This is a flowchart showing an example of a process procedure executed by FDC-ECU 60 at the time of Ready-on in Embodiment 3. A series of processes shown in this flowchart starts at the time of Ready-on.

[0111] Reference Fig. 9 , the FDC-ECU 60 obtains the SOC of the battery 40 from the battery ECU 64, and determines whether the SOC is lower than the threshold value S1 ( Figure 3 ) (Step S410 ). If the SOC is equal to or higher than the threshold value S1 (No in Step S410 ), the subsequent series of processes are not executed and the process is terminated.

[0112] When it is determined in step S410 that the SOC is lower than the threshold value S1 (YES in step S410), the FDC-ECU 60 and the mode switch 62 ( Figure 1 ) state to perform FC charging (step S420). Specifically, FDC-ECU 60 sets the target SOC of battery 40 to S2 which is higher than threshold value S1, and drives boost converter 24 of FC system 20 to supply power from FC system 20 to battery 40.

[0113] During FC charging, FDC-ECU 60 determines whether SOC of battery 40 exceeds S2 (S2>threshold S1) (step S430). If SOC increases due to FC charging and it is determined that SOC exceeds S2 (YES in step S430), FDC-ECU 60 terminates FC charging and moves the process to end.

[0114] It should be noted that, although not particularly shown, the FDC-ECU 60 then follows the mode switch 62 ( Figure 1 ) to switch the driving mode.

[0115] As described above, in the third embodiment, FC charging is performed when the SOC is lower than the threshold value S1 at the time of Ready-on, so that the system output can be prevented from being limited due to a decrease in the SOC. Therefore, according to the third embodiment, a decrease in the running performance after Ready-on can be suppressed.

[0116] It should be noted that the third embodiment may be combined with the first embodiment and its variants and the second embodiment. That is, it may be configured that: when the SOC is lower than the threshold value S1 at the time of Ready-off, the processing shown in the first embodiment and its variants and the second embodiment is executed, and the processing shown in the next Ready-on is further executed. Fig. 9 Processing shown.

[0117] The embodiments of the present disclosure have been described above, but the embodiments disclosed herein are illustrative in all aspects and are not restrictive. The scope of the present invention is indicated by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

Claims

1. A fuel cell vehicle comprising: Fuel cell systems; Electricity storage device; a driving device that receives electric power from at least one of the fuel cell system and the power storage device to generate running power; and a charging device for performing external charging, wherein the external charging charges the power storage device through a power source external to the fuel cell vehicle, The output upper limit of the power storage device is set such that, when the state of charge of the power storage device is lower than a first threshold value which is smaller than 100%, the output upper limit of the power storage device decreases as the state of charge decreases. Furthermore, the fuel cell vehicle is provided with a control device, which controls the fuel cell system so that when the state of charge is lower than the first threshold value when the system of the fuel cell vehicle is stopped and the external charging is not performed, fuel cell charging that supplies power from the fuel cell system to the power storage device is started, and the power storage device is charged by the fuel cell charging until the state of charge exceeds a second threshold value that is higher than the first threshold value.

2. The fuel cell vehicle according to claim 1, wherein: The control device controls the fuel cell system so that, when the state of charge is lower than the first threshold value when the system is stopped, the fuel cell is charged when a prescribed operation for performing the external charging is not performed for a prescribed time after the system is stopped.

3. The fuel cell vehicle according to claim 2, wherein: When the operation is performed during execution of the fuel cell charging, the control device stops the fuel cell charging and executes the external charging.

4. The fuel cell vehicle according to claim 2 or 3, wherein: The control device controls the fuel cell system so that, when the operation is performed, if the electricity charge generated by the external charging is higher than a prescribed amount, the external charging is not performed but the fuel cell charging is performed.

5. The fuel cell vehicle according to any one of claims 1 to 3, wherein: The control device controls the fuel cell system so that the fuel cell is charged when the state of charge is lower than the first threshold value when the system of the fuel cell vehicle is started.

6. A fuel cell vehicle comprising: Fuel cell systems; Electricity storage device; a driving device that receives electric power from at least one of the fuel cell system and the power storage device to generate running power; a charging device for performing external charging, wherein the external charging charges the power storage device through a power source external to the fuel cell vehicle; as well as A display device capable of being operated by a user of the fuel cell vehicle, The output upper limit of the power storage device is set such that, when the state of charge of the power storage device is lower than a first threshold value which is smaller than 100%, the output upper limit of the power storage device decreases as the state of charge decreases. Furthermore, the fuel cell vehicle includes a control device that controls the fuel cell system so that when the state of charge is lower than the first threshold value when the system of the fuel cell vehicle is stopped, the control device displays on the display device an operation unit for instructing a user to perform fuel cell charging for supplying power from the fuel cell system to the power storage device, and charges the power storage device through the fuel cell charging until the state of charge exceeds a second threshold value that is higher than the first threshold value.

Images