Vehicle control device, computer program, and recording medium

Abstract

To provide a control device for a vehicle capable of suppressing deterioration of a fuel battery (such as an electrolyte film) even during no power generation or during low output power generation, a computer program and a recording medium.SOLUTION: The present invention relates to a control device comprising one or more processors and one or more memories communicably connected to the one or more processors. In the control device, the processor detects a valve opening point at a time point when a fuel battery starts generating power and a cell voltage starts rising regarding at least one of a suction valve which supplies air to the fuel battery and an exhaust valve which exhausts air from the fuel battery and determines a manipulated variable of the valve at the time when the cell voltage starts rising as the valve opening point based on a correlation between an opening / closing signal of the valve and the rising start of the cell voltage.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a control device, a program, and a recording medium capable of executing valve control for supplying at least oxygen to a fuel cell mounted on a vehicle, for example. [Background technology]

[0002] In modern society, transportation is essential, and various vehicles, including automobiles, travel on the roads in our daily lives. In recent years, fuel cells, which have a relatively low environmental impact, have been attracting attention as a new power source for supplying driving force to vehicles.

[0003] In such fuel cells, fuel gas (hydrogen) is supplied to one electrode (fuel electrode) and oxidant gas (oxygen) is supplied to the other electrode (air electrode), and electrical energy is generated through a chemical reaction between these. Therefore, in order to obtain appropriate electrical energy (generated power) from a fuel cell, it is necessary to supply the fuel gas and oxidant gas to the fuel cell in the correct amounts.

[0004] For example, Patent Document 1 discloses that in order to control the pressure of the oxidant gas supplied to the oxidant electrode even when the surrounding atmospheric pressure or the temperature inside the fuel cell changes, the manipulated variable of the pressure control means is calculated using a relative value between the target pressure of the oxidant gas supplied to the oxidant electrode and the atmospheric pressure around the fuel cell system, and a physical quantity representing the amount of oxidant gas supplied to the oxidant electrode.

[0005] Furthermore, fuel cells generally have the property that the energy efficiency of the entire system decreases when the power generation is very small. For this reason, for example, Patent Document 2 discloses a degradation suppression technology in which a first target voltage is set as the target voltage when the fuel cell is in a first low-load state and oxygen is supplied to the fuel cell, and then a second target voltage lower than the first target voltage is set as the target voltage when the fuel cell enters a second low-load state. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-099988 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-096087 Summary of the Invention [Problem to be solved by the invention]

[0007] Not limited to the above-mentioned patent documents, current technologies still do not meet market needs, and the following problems remain. In other words, as shown in the above-mentioned patent documents, in order to efficiently generate electrical energy through optimal chemical reactions, it is important to appropriately control the supply amounts of oxygen and hydrogen while suppressing deterioration of the fuel cell.

[0008] In particular, the electrolyte membrane of a fuel cell can chemically deteriorate and develop pinholes or other damage when it is not generating electricity or when there is extremely low current and high voltage (hereinafter, this condition is also referred to as a "degraded environment" as an example). More specifically, fuel cell voltage control depends on the initial opening of the intake valve, which controls the amount of oxygen supplied to the fuel cell, and the exhaust valve, which controls the exhaust gas discharged from the fuel cell. Therefore, it is important to appropriately set the valve opening at the start of control; neglecting this can result in the fuel cell entering the degraded environment described above.

[0009] The present disclosure has been made in consideration of the above-mentioned problems as an example, and aims to provide a vehicle control device, computer program, and recording medium that can suppress deterioration of a fuel cell (electrolyte membrane, etc.). [Means for solving the problem]

[0010] In order to solve the above problems, according to one aspect of the present disclosure, there is provided a control device comprising one or more processors and one or more memories communicably connected to the one or more processors, wherein the processor detects a valve opening point for at least one of an intake valve that supplies air to a fuel cell and an exhaust valve that exhausts air from the fuel cell, at the time when the fuel cell starts to generate electricity and a cell voltage starts to rise, and determines, based on a correlation between an opening / closing signal of the valve and the start of the rise in the cell voltage, the operation amount of the valve at the time when the cell voltage starts to rise, as the valve opening point. After the intake valve and the exhaust valve are fully closed, a predetermined measurement current is applied to reduce the open circuit voltage to a minimum voltage, and then a signal is sent to gradually open the intake valve, and the valve operation amount when the cell voltage begins to rise from the minimum voltage is stored as the initial value of the intake valve. A control device is provided for: [Effects of the Invention]

[0011] According to the present disclosure, it is possible to suppress deterioration of the electrolyte membrane and the like, even when the fuel cell is not generating electricity or is generating low-output electricity, for example. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a schematic diagram showing an example of the configuration of a vehicle equipped with a control device according to an embodiment of the present invention; [Figure 2] FIG. 2 is a schematic diagram showing the connection relationship between the control device and each valve according to the present embodiment. [Figure 3] FIG. 2 is a block diagram showing an example of the configuration around the control device according to the present embodiment. [Figure 4] 4 is a flowchart showing an example of a method for controlling the oxygen intake valve in the fuel cell according to the present embodiment. [Figure 5] 4 is a graph showing an example of the relationship between the valve opening and the operation amount. [Figure 6] 4 is a flowchart showing an example of a method for controlling an oxygen exhaust valve in a fuel cell according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] Next, preferred embodiments of the present disclosure will be described. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted. Furthermore, configurations other than those described in detail below may be supplemented appropriately with elemental technologies and configurations related to known fuel cell systems and fuel cell vehicles, including those described in the patent documents mentioned above.

[0014] <Vehicle 100> Fig. 1 is a schematic diagram showing an example of the configuration of a vehicle 100 as a fuel cell vehicle equipped with a fuel cell 1 and its control device 10 according to this embodiment. The vehicle 100 shown in Fig. 1 is configured as a four-wheel drive vehicle in which drive torque output from a drive power source 21 that generates drive torque for the vehicle is transmitted to a left front wheel 3LF, a right front wheel 3RF, a left rear wheel 3LR, and a right rear wheel 3RR (hereinafter collectively referred to as "wheels 3" unless a distinction is required). In this embodiment, the drive power source 21 can be, for example, a known electric motor arranged on the front wheel side.

[0015] The electric motors serving as driving force source 21 in this embodiment may be arranged one on each of the front and rear wheels, or one electric motor may be arranged for each wheel 3. In addition to the electric motor described above, driving force source 21 may also include an internal combustion engine such as a gasoline engine, a diesel engine, or a gas turbine engine.

[0016] A power supply system that supplies desired electric power to such driving force source 21 includes fuel cell 1, a hydrogen gas supply unit including a known hydrogen tank 23 and piping, an air supply unit including a known compressor 31 and piping, a known secondary battery 50 such as a lithium ion secondary battery or a lead storage battery, a converter 22, and a control device 10 that controls these. In this power supply system, each of fuel cell 1 and secondary battery 50 can supply electric power to a load including the electric motor described above.

[0017] The fuel cell 1 has a stack structure in which a plurality of well-known unit cells are stacked. As an example, the fuel cell 1 of this embodiment can be a polymer electrolyte fuel cell (PEFC). Each unit cell constituting the fuel cell 1 has an anode flow path through which hydrogen flows to the anode side via a well-known electrolyte membrane, and a cathode flow path through which oxygen flows to the cathode side. As shown in FIG. 1, the fuel cell 1 is connected to a load including a driving force source 21 (electric motor) via a converter 22 and wiring. The cell voltage of the fuel cell 1 is detected by a well-known voltage sensor 43 (see FIG. 2).

[0018] Converter 22 includes a known AC / DC converter that converts DC current to AC current, and a known DC / DC converter that adjusts the voltage of DC current to a desired voltage. As an example, converter 22 of this embodiment has a function of receiving a control signal from control device 10 to set the output voltage generated and output by fuel cell 1, and a function of boosting the power generated by fuel cell 1 to a desired voltage when supplying it to a load.

[0019] The vehicle 100 of this embodiment also includes the above-mentioned driving force source 21, electric steering device 8, and brake devices 4LF, 4RF, 4LR, and 4RR (hereinafter collectively referred to as "brake device 4" unless a distinction is required) as equipment used for driving control. The driving force source 21 outputs driving torque that is transmitted to the front drive shaft 2F and the rear drive shaft 2R via a transmission, a front wheel differential mechanism 5F, and a rear wheel differential mechanism 5R (not shown). The driving of the driving force source 21 and the transmission is controlled by a vehicle drive control device 20 that includes one or more electronic control units (ECUs: Electronic Control Units).

[0020] The front wheel drive shaft 2F is provided with an electric steering device 8. The electric steering device 8 includes an electric motor and a gear mechanism (not shown), and is controlled by a vehicle drive control device 20 to adjust the steering angles of the left front wheel 3LF and the right front wheel 3RF.

[0021] The vehicle drive control device 20 includes one or more known electronic control units (ECUs) that control the drive of a drive force source 21 that outputs drive torque for the vehicle 100, an electric steering device 8 that controls the steering wheel 9 or the steering angle of the steered wheels, and a brake device 4 that controls the braking force of the vehicle 100. The vehicle drive control device 20 may also have a function of controlling the drive of a transmission that changes the speed of the output from the drive force source 21 and transmits it to the wheels 3.

[0022] [Intake and exhaust valve configuration] Next, the configuration of each valve in the vehicle 100 of this embodiment will be described with reference to FIG. First, the above-mentioned hydrogen gas supply unit may include a pipe (hydrogen supply flow path FC1) connecting the hydrogen tank 23 to the fuel cell 1, a pipe (circulation flow path FC2) for circulating the anode off-gas discharged from the fuel cell 1 to the above-mentioned hydrogen supply flow path, and a pipe (hydrogen release flow path FC3) for releasing the anode off-gas into the atmosphere.

[0023] In this hydrogen gas supply section, hydrogen gas stored in hydrogen tank 23 is supplied to the anode-side flow path of fuel cell 1 via a hydrogen intake valve 32a, a pressure reducing valve, an injector (none of which are shown), and other components having known structures that are installed in hydrogen supply flow path FC1. The flow rate of hydrogen circulating through circulation flow path FC2 is adjusted by a known circulation pump 45. The amount of hydrogen supplied to fuel cell 1 by the injector and the drive rate of circulation pump 45 are adjusted by control device 10 in accordance with the load requirements within vehicle 100.

[0024] A portion of the hydrogen gas flowing through the circulation flow path FC2 is released (exhausted) to the atmosphere at a predetermined timing through the opening and closing operation of a hydrogen exhaust valve 32b installed in a hydrogen release flow path FC3 branching off from the circulation flow path FC2 under the control of the control device 10. This makes it possible to discharge impurities (such as water vapor and nitrogen) in the hydrogen gas circulating within the circulation flow path FC2 to the outside of the system.

[0025] On the other hand, in addition to the above-mentioned compressor 31, the air supply unit may also include an air supply flow path FC4 in which this compressor 31 is installed and which is connected to the fuel cell 1, an oxygen intake valve 32c which is installed in this air supply flow path FC4 and which adjusts the amount of oxygen (air) supplied to the fuel cell 1, a flow dividing valve 44, an air release flow path FC5, an air branch flow path FC6, an air exhaust valve (back pressure valve) 32d, and a known flow sensor (not shown). The air supply flow path FC4 is composed of known piping that supplies the air taken in by the above-mentioned compressor 31 to the fuel cell 1.

[0026] The flow dividing valve 44 is a known valve mechanism installed in this air supply flow path FC4, and has the function of adjusting the amount of air that is not supplied to the fuel cell 1 but is supplied directly to the diluter 41 via the air branch flow path FC6. There are no particular restrictions on the structure of the diluter 41, and various known diluters that can be mounted on a vehicle may be used.

[0027] The air taken in by the compressor 31 is supplied to the cathode-side flow path in the fuel cell 1 via the oxygen intake valve 32c and a known humidifier 42. The air supplied to the fuel cell 1 is also supplied as cathode off-gas to a known diluter 41 via an air discharge flow path FC5 under the control of the oxygen discharge valve (back pressure valve) 32d by the control device 10.

[0028] The control device 10 can adjust the concentration of hydrogen gas supplied to the diluter 41 to a predetermined concentration or less (for example, 4% or less) by controlling the flow dividing valve 44. The humidifier 42 of this embodiment may be omitted as appropriate.

[0029] <Control device 10> Next, with reference to FIG. 3, the functions of the control device 10 according to this embodiment and the connection relationships between the various elements in the vehicle 100 will be specifically described. As shown in the figure, the control device 10 of this embodiment is configured to include one or more processors (CPUs (Central Processing Units)) and one or more memories MR communicatively connected to the one or more processors. The control device 10 may be configured to be connectable to a known external network NET such as the Internet via various known communication devices 36, such as a smartphone. Note that in FIG. 3, the memory MR is depicted as one of the storage devices 40 separate from the control device 10, but the storage device 40 may also be built into the control device 10.

[0030] Furthermore, the control device 10 of the present embodiment described above has a function of detecting the valve opening point at which the cell voltage begins to rise after the fuel cell 1 starts power generation, for at least one of the oxygen intake valve 32c that supplies air to the fuel cell 1 and the oxygen exhaust valve 32d that exhausts air from the fuel cell 1. More specifically, as will be described in detail later, the control device 10 performs control to determine the valve opening degree at which the cell voltage begins to rise as the valve opening point (initial value) based on the correlation between the valve opening / closing signal and the start of the cell voltage rise.

[0031] Such a control device 10 is electrically connected, either directly or via communication means such as CAN (Controller Area Network) or LIN (Local Internet), to a compressor 31, a valve group 32 (hydrogen intake valve 32a, hydrogen exhaust valve 32b, oxygen intake valve 32c, and oxygen exhaust valve 32d), sensors 33, a publicly known navigation device 34 and notification device 35 (speaker SP and display DP), a communication device 36, a memory device 40, and the like.

[0032] Of these, the storage device 40 may be composed of a known memory MR such as RAM (Random Access Memory) or ROM (Read Only Memory), and a known hard disk HDD such as a hard disk. However, the configuration of the storage device 40 is not limited to the above configuration, and the hard disk HDD may be omitted. The storage device 40 may store information such as computer programs executed by the control device 10, various parameters used in arithmetic processing, detection data, and arithmetic results.

[0033] Furthermore, the sensors 33 may be configured to include one or more sensors that detect, for example, the operating state and behavior of the vehicle 100 (hereinafter collectively referred to as the "vehicle running state") and the environment around the vehicle 100. As an example, the sensors 33 of this embodiment may include a known humidity sensor 33a that detects the humidity around the vehicle 100, and a known outside air temperature sensor 33b that detects the outside air temperature around the vehicle 100. Furthermore, the sensors 33 may include various known sensors that are mounted on a vehicle, such as a vehicle speed sensor and an acceleration sensor.

[0034] The control device 10 of this embodiment is electrically connected to the above-mentioned vehicle drive control device 20 directly or via communication means such as a CAN (Controller Area Network) or a LIN (Local Internet). The control device 10 may also be connected to a known HMI and a head-up display (not shown).

[0035] 3, the control device 10 is configured to include a compressor drive unit 11 that controls the drive of the compressor 31, a valve control unit 12 that controls each of the valve groups 32, a cell voltage acquisition unit 13 that acquires the cell voltage of the fuel cell 1 via a voltage sensor 43, a valve opening point determination unit 14 that determines the valve opening point of at least one of the valve groups 32, an initial opening degree setting unit 15 that sets an initial opening degree of the valve based on the valve opening point, and a notification control unit 16. Note that part or all of this control device 10 may be configured with updatable firmware or the like, or may be a program module or the like that is executed by commands from a CPU or the like.

[0036] <Method for determining the valve opening point and setting the initial opening of the oxygen intake valve> Next, with reference to FIGS. 4 and 5, a method for determining the valve opening point and setting the initial opening degree of the oxygen intake valve 32c that can be performed by the control device 10 of this embodiment will be described. As pointed out in the above-mentioned Patent Document 2, the electrolyte membrane constituting the fuel cell 1 may chemically deteriorate and develop pinholes in degrading environments, such as when not generating electricity (i.e., when the fuel cell 1 is not generating electricity) and at high voltage, or when generating low-output electricity and at high voltage.

[0037] Therefore, in order to suppress such deterioration, it is important to control the cell voltage by lowering the oxygen partial pressure in the fuel cell 1. However, in actual control, the time until the cell voltage is controlled varies greatly depending on the opening degree (initial opening degree) of the oxygen intake valve and oxygen exhaust valve at the start of control. Based on this knowledge, in this embodiment, by setting the opening (initial opening) at the start of control of at least one of the oxygen intake valve 32c and the oxygen exhaust valve 32d, a quick transition from the voltage control start decision to the voltage suppression state during non-power generation and low-output power generation as described above is achieved.

[0038] The determination of the valve opening point and the setting of the initial opening degree by the control device 10, which will be described below, are performed at a predetermined timing in the vehicle 100. Such a predetermined timing is before the fuel cell 1 is driven and enters the above-mentioned deteriorating environment, and examples of such timing include when the vehicle 100 is started, when the fuel cell 1 is activated, when idling for a predetermined period of time (e.g., 60 seconds) or longer is detected, or when the fuel cell 1 executes non-power generation control for the first time after the vehicle 100 has been started.

[0039] 4, in step S11, the control device 10 determines whether a predetermined timing has arrived for determining the valve opening point and setting the initial opening degree. As a specific example, in step S11, the control device 10 determines whether the non-power generation control described above will be started for the first time in the fuel cell 1 after the start of the vehicle 100. If the non-power generation control has not yet been started in the fuel cell 1 (No in step S11), the process of step S11 is repeated, whereas if it is determined that the non-power generation control will be started (Yes in step S11), the process proceeds to step S12, where the process of determining the valve opening point and the process of setting the initial opening degree are executed.

[0040] In this embodiment, the valve opening point determination process and the initial opening setting process are executed based on whether or not non-power generation control is started for the first time after the vehicle 100 is started (a predetermined timing). However, the trigger does not necessarily have to be the start of non-power generation control, and other triggers may be used, such as the start of the vehicle 100 as described above.

[0041] Next, in step S12, the valve control unit 12 of the control device 10 controls the oxygen intake valve 32c and the oxygen exhaust valve 32d to fully close each valve. As a result, the oxygen intake valve 32c is fully closed, which prevents oxygen (air) from being supplied to the fuel cell 1 via the compressor 31, and also prevents cathode off-gas from being discharged from the fuel cell 1 via the oxygen exhaust valve 32d. At this time, the compressor drive unit 11 of the control device 10 may perform control to suppress the output of the compressor 31.

[0042] Then, after the oxygen intake valve 32c and the oxygen exhaust valve 32d are fully closed in step S12, the control device 10 applies a predetermined measurement current to the fuel cell 1 in the following step S13 to control the open circuit voltage (OCV) of the fuel cell 1 to drop to a predetermined minimum value Vs. That is, as shown in Figure 5(a), the control device 10 applies a measurement current to the fuel cell 1, causing the cell voltage of the fuel cell 1 to drop towards time t0.

[0043] The predetermined measurement current may be any value that allows the open circuit voltage to be measured, and may be, for example, 0.01 A to 1 A. In this case, the minimum value Vs of the open circuit voltage is preferably, for example, within the range of 0.2 V to 0.5 V.

[0044] Then, in step S14, the control device 10 determines whether the cell voltage of the fuel cell 1 (the above-mentioned OCV) has reached a predetermined value. After determining that the cell voltage of the fuel cell 1 has dropped to the predetermined value (i.e., the state at time t0 in FIG. 5(a)), the control device 10 stops applying the measurement current to the fuel cell 1 and executes control to gradually open the oxygen intake valve 32c in the following step S15. More specifically, in step S15, the control device 10 executes control to send a signal to the oxygen intake valve 32c to gradually open the valve (i.e., a signal to gradually increase the amount of valve operation).

[0045] 5(b), each valve constituting the valve group 32 has a buffer region BA as valve play, similar to the play of a steering wheel. Therefore, for example, when the control device 10 executes control to open the oxygen intake valve 32c, oxygen is not immediately supplied to the fuel cell 1. In other words, the oxygen intake valve 32c of this embodiment is in the buffer region BA immediately after the control device 10 starts control to open the oxygen intake valve 32c, and even if the valve is opened, the valve operation amount and the opening degree are not proportional, and the valve opening degree remains fully closed.

[0046] Then, in step S15, the application of the measurement current to the fuel cell 1 is stopped and control to gradually open the oxygen intake valve 32c continues. As the amount of valve operation increases, the valve opening increases, passing through the buffer region BA described above and transitioning from the fully closed state to the open state, as shown in Figure 5(b). At this time, when the valve opening transitions from the fully closed state to the open state via the buffer region BA, oxygen (air) is supplied to the fuel cell 1 via the oxygen intake valve 32c, and the cell voltage of the fuel cell 1 begins to rise from the minimum value Vs.

[0047] At this time, in step S16, the cell voltage acquisition unit 13 of the control device 10 acquires the cell voltage of the fuel cell 1 via the voltage sensor 43, and executes control to determine whether or not the cell voltage has risen from the minimum value Vs.

[0048] If an increase in the cell voltage of the fuel cell 1 is detected in step S16, then in step S17, the valve opening point determination unit 14 of the control device 10 determines that the point at which the valve opening transitions from the fully closed state to the open state is the valve opening point VOP. Furthermore, the initial opening setting unit 15 of the control device 10 executes control to store the valve operation amount corresponding to the valve opening point VOP determined by the valve opening point determination unit 14 as the initial value of the oxygen intake valve 32c (the start point at which the valve opens and oxygen starts to be supplied to the fuel cell 1), as shown in Fig. 5(b).

[0049] Then, in the next step S18, the control device 10 determines whether the system of the vehicle 100 has been turned off due to arrival at the destination, etc. If the answer is Yes in step S18, the process is completed, whereas if the answer is No in step S18, the process returns to step S11 and continues as described above.

[0050] According to the method for determining the valve opening point and setting the initial opening degree of the oxygen intake valve in this embodiment described above, it is possible to set the initial value by accurately detecting the valve operation amount at which oxygen supply to the fuel cell 1 actually starts, taking into account individual variations in each valve. This makes it possible to shorten the time from the start of non-power generation control in the fuel cell 1 to voltage suppression, thereby suppressing deterioration of the electrolyte membrane.

[0051] The above-described embodiment is a preferred example of the present disclosure, and new structures and controls may be realized by appropriately combining the elements of the embodiment without departing from the spirit of the present disclosure. Modifications that can be applied to the present embodiment will be described below.

[0052] [Variations] <Method for determining the valve opening point and setting the initial opening for an oxygen exhaust valve> Next, with reference to FIG. 6 as well, a method for determining the valve opening point and setting the initial opening degree of the oxygen exhaust valve 32d, which can be performed by the control device 10 of this embodiment, will be described.

[0053] As shown in FIG. 6, in step S21, the control device 10 determines whether or not a predetermined timing has arrived for determining the valve opening point and setting the initial opening degree, in the same manner as in step S11 described above.

[0054] If the predetermined timing has not yet arrived in the fuel cell 1 (No in step S21), the process of step S21 is repeated, whereas if it is determined that the predetermined timing has arrived (Yes in step S21), the process proceeds to step S22, where the valve opening point determination process and the initial opening degree setting process are executed.

[0055] Next, in step S22, the valve control unit 12 of the control device 10 controls the oxygen intake valve 32c and the oxygen exhaust valve 32d to fully close each valve. As a result, the oxygen intake valve 32c is fully closed, which stops oxygen (air) from being supplied to the fuel cell 1 via the compressor 31, and also stops cathode off-gas from being discharged from the fuel cell 1 via the oxygen exhaust valve 32d.

[0056] Then, after the oxygen intake valve 32c and the oxygen exhaust valve 32d are fully closed in step S22, the control device 10 applies the above-mentioned predetermined measurement current to the fuel cell 1 in the following step S23 to control the cell voltage (i.e., OCV) of the fuel cell 1 to drop to the above-mentioned predetermined minimum value Vs.

[0057] Then, in step S24, the control device 10 determines whether the cell voltage of the fuel cell 1 (the above-mentioned OCV) has reached a predetermined value, in the same manner as in step S14 above. After it is determined that the cell voltage of the fuel cell 1 has dropped to the above-mentioned predetermined value, the control device 10 stops applying the above-mentioned measurement current to the fuel cell 1 and executes control to gradually open the oxygen exhaust valve 32d in the following step S25. More specifically, in step S25, the control device 10 executes control to send to the oxygen exhaust valve 32d a signal to gradually open the valve (i.e., a signal to gradually increase the amount of operation of the valve).

[0058] Then, in step S25, when the application of the measurement current to the fuel cell 1 is stopped and control is executed to gradually open the oxygen exhaust valve 32d, the valve opening changes from the fully closed state to the open state and increases via the buffer region BA. At this time, when the valve opening changes from the fully closed state to the open state via the buffer region BA, cathode off-gas is exhausted from the fuel cell 1 via the oxygen exhaust valve 32d, and the cell voltage of the fuel cell 1 starts to increase from the minimum value Vs.

[0059] At this time, in step S26, the cell voltage acquisition unit 13 of the control device 10 acquires the cell voltage of the fuel cell 1 via the voltage sensor 43, and executes control to determine whether or not the cell voltage has risen from the minimum value Vs.

[0060] If an increase in the cell voltage of the fuel cell 1 is detected in step S26, then in step S27, the valve opening point determination unit 14 of the control device 10 determines the point at which the valve opening degree transitions from a fully closed state to an open state as the valve opening point VOP.

[0061] In addition, the initial opening setting unit 15 of the control device 10 performs control to store the valve operation amount corresponding to the valve opening point VOP determined by the valve opening point determination unit 14 as the initial value of the oxygen exhaust valve 32d (i.e., the starting point at which the valve opening opens and cathode off-gas is discharged from the fuel cell 1).

[0062] Then, in the next step S28, the control device 10 determines whether the system of the vehicle 100 has been turned off in the same manner as in step S18. If the result in step S18 is Yes, the control device 10 ends this process, whereas if the result in step S18 is No, the control device 10 returns to step S11 and continues the above process.

[0063] The above-described first modification also takes into account the individual variations of the individual valves and accurately detects and sets the operation amount of the valve at which the cathode off-gas is actually discharged from the fuel cell 1. This makes it possible to suppress deterioration of the electrolyte membrane, as in the above-described embodiment.

[0064] In the above-described embodiment and modified examples, the oxygen intake valve and oxygen exhaust valve that control the supply and discharge of oxygen to and from the fuel cell 1 have been described, but the present disclosure is not limited to this aspect. In other words, the above-described method for determining the valve opening point and method for setting the initial opening degree may also be applied to at least one of the hydrogen intake valve and hydrogen exhaust valve that control the supply and discharge of hydrogen to and from the fuel cell 1. [Explanation of symbols]

[0065] 10 Control device 31 Compressor 32 Valve group 33 Sensors 100 vehicles

Claims

1. one or more processors; one or more memories communicatively coupled to the one or more processors; A control device comprising: The processor: detecting a valve opening point of at least one of an intake valve for supplying air to the fuel cell and an exhaust valve for exhausting air from the fuel cell at a point when the fuel cell starts generating electricity and a cell voltage starts to increase; determining, as the valve opening point, the operation amount of the valve when the cell voltage starts to increase, based on a correlation between the valve opening / closing signal and the start of the increase in the cell voltage; After the intake valve and the exhaust valve are fully closed, a predetermined measurement current is applied to reduce the open circuit voltage to a minimum voltage, and then a signal is sent to gradually open the intake valve, thereby storing the valve operation amount when the cell voltage begins to rise from the minimum voltage as the initial value of the intake valve. Control device.

2. The processor: After the intake valve and the exhaust valve are fully closed, a predetermined measurement current is applied to reduce the open circuit voltage to the minimum voltage; Then, by sending a signal to gradually open the exhaust valve, the operation amount of the valve when the cell voltage starts to rise from the minimum voltage is stored as an initial value of the exhaust valve. The control device according to claim 1 .

3. the valve opening point is determined before non-power generation control is executed for the first time after the fuel cell is started up; The control device according to claim 1 or 2.

4. an intake valve for controlling the amount of air supplied to the fuel cell; an exhaust valve for controlling the amount of air exhausted from the fuel cell; The control device according to any one of claims 1 to 3; A fuel cell vehicle with

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