JP6856502B2 - Power supply system and control method of power supply system - Google Patents

Description

The present invention relates to a power supply system including a discharge resistor and a control method thereof.

Patent Document 1 provides a fuel cell system capable of eliminating an offset that may occur when the start time of the fuel cell is long by performing origin learning of the current sensor of the converter and adjusting the zero point. It is intended to be provided ([0006], summary). In order to achieve this object, the fuel cell system of Patent Document 1 (summary) includes a cell stack 3, a converter 150 that boosts the output voltage of the cell stack 3, a switching element SW1 provided in the converter 150, and a cell stack. It is provided with a current sensor CS that measures the current sent from 3 to the converter 150. A learning processing means for performing origin learning of the current sensor CS (FIG. 2) is provided when the switching element SW1 is stopped and the output voltage V _H of the converter 150 _{is larger than the input voltage V L to the converter 150.} ..

Japanese Unexamined Patent Publication No. 2012-248421

As described above, Patent Document 1 discloses origin learning of one current sensor CS (FIG. 2). However, Patent Document 1 does not study a configuration using a plurality of current sensors (current value acquisition means) and a control for that purpose.

The present invention has been made in consideration of such a problem, and an object of the present invention is to provide a power supply system capable of preferably using a plurality of current value acquisition means and a control method thereof.

The power supply system according to the present invention
Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first current acquisition means for acquiring a first current in the negative electrode line on the power supply side of the discharge resistor, and
It is provided with a second current acquisition means for acquiring a second current in the negative electrode line on the load side of the discharge resistor.
The power supply system further comprises a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first current and the second current are different, the switch is turned on to start the discharge by the discharge resistor, and the first before the start of the discharge and after the start of the discharge. It is characterized by estimating the faulty part based on the change in current.

According to the present invention, when it is determined that the first current in the negative electrode line on the power supply side of the discharge resistor and the second current in the negative electrode line on the load side of the discharge resistor are different, the discharge by the discharge resistor is performed. To start. Then, the failure portion is estimated based on the change in the first current before and after the start of discharge. Therefore, it is possible to estimate the faulty part by a simple method.

When the first current changes before and after the start of discharge, the diagnostic unit may presume that at least one of the first current acquisition means and the second current acquisition means has failed. This makes it possible to detect a failure of the first current acquisition means or the second current acquisition means by a simple method. Further, if the first current acquisition means or the second current acquisition means fails, control using the first current and the second current (for example, zero point learning, output correction, etc.) cannot be properly performed. According to the present invention, since it is possible to detect a failure of the first current acquisition means or the second current acquisition means, it is possible to easily detect a situation in which control using the first current and the second current is not properly performed. It will be possible.

When the first current before the start of discharge and after the start of discharge have the same value, the diagnostic unit may presume that the switch is closed and fixed. This makes it possible to detect the closing and sticking of the switch by a simple method. Further, when the switch arranged in series with the discharge resistor is closed and fixed, the first current acquisition means and the second current acquisition means detect the first current and the second current as erroneous values that should not be originally present. It will be. In that case, control using the first current and the second current (for example, zero point learning, output correction, etc.) is not properly performed. According to the present invention, since it is possible to detect the closing and sticking of the switch, it is possible to easily detect a situation in which control using the first current and the second current is not properly performed. Furthermore, when identifying the cause location according to whether the first current before and after the start of discharge, which is performed when it is determined that the first current and the second current are different, has changed or is the same, fail-safe measures are provided. It will be possible to take it properly.

The power source can be, for example, a fuel cell. The power supply system may include zero point learning means for executing zero point learning control for learning the zero point of the first current acquisition means or the second current acquisition means. The zero point learning means sets as the execution conditions of the zero point learning control that an open command is given to the switch and that the output voltage of the fuel cell is equal to or less than the first voltage threshold value or does not fluctuate. You may. As a result, the zero point learning of the first current acquisition means or the second current acquisition means can be performed when the conditions suitable for the zero point learning are satisfied.

The power supply system may include acquisition value correction means for executing acquisition value correction control for correcting the acquisition value of the other based on the acquisition value of one of the first current acquisition means and the second current acquisition means. The acquired value correction means may set that the output voltage of the fuel cell is equal to or higher than the second voltage threshold value as an execution condition of the acquired value correction control. As a result, it is possible to correct the acquired value of the first current acquisition means or the second current acquisition means when the conditions suitable for the correction of the acquired value are satisfied.

The control method of the power supply system according to the present invention is
Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first current acquisition means for acquiring a first current in the negative electrode line on the power supply side of the discharge resistor, and
A second current acquisition means for acquiring a second current in the negative electrode line on the load side of the discharge resistor, and
It is a control method of a power supply system including a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first current and the second current are different, the switch is turned on to start the discharge by the discharge resistor, and the first before the start of the discharge and after the start of the discharge. It is characterized by estimating the faulty part based on the change in current.

The power supply system according to the present invention
Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first energized state amount acquisition means for acquiring a first energized state amount on the power supply side of the discharge resistor, and
It is provided with a second energized state amount acquisition means for acquiring the second energized state amount on the load side of the discharge resistor.
The power supply system further comprises a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first energized state amount and the second energized state amount are different, the switch is turned on to start the discharge by the discharge resistor, and before the start of the discharge and after the start of the discharge. The faulty part is estimated based on the change of the first energized state amount or the second energized state amount of the above.

According to the present invention, when it is determined that the first energized state amount on the power supply side of the discharge resistor and the second energized state amount on the load side of the discharge resistor are different, the discharge by the discharge resistor is started. Let me. Then, the failure portion is estimated based on the change in the first energized state amount or the second energized state amount before and after the start of discharge. Therefore, it is possible to estimate the faulty part by a simple method.

The first energized state amount or the second energized state amount for determining whether or not they are different, and the first energized state amount or the second energized state amount for observing the change before and after the start of discharge are the same. It may be of any type (current, voltage, power, etc.) or a different type.

According to the present invention, it is possible to preferably use a plurality of current value acquisition means.

FIG. 5 is a schematic overall configuration diagram of a fuel cell vehicle (hereinafter referred to as “FC vehicle” or “vehicle”) equipped with a power supply system (hereinafter referred to as “system”) according to an embodiment of the present invention. It is a schematic overall block diagram of the FC unit of the said embodiment. It is a flowchart of failure diagnosis control in the said embodiment. 6 is a time chart showing various signals and values when the failure diagnosis control in the embodiment is being executed. It is a flowchart of zero point learning control in the said embodiment. It is a flowchart of the output map correction control in the said embodiment. It is a figure which shows the current-voltage characteristic of the FC stack in the said embodiment.

A. One Embodiment <A-1. Configuration>
[A-1-1. overall structure]
FIG. 1 shows a schematic overall configuration of a fuel cell vehicle 10 (hereinafter referred to as “FC vehicle 10” or “vehicle 10”) equipped with a power supply system 12 (hereinafter referred to as “system 12”) according to an embodiment of the present invention. It is a figure. The FC vehicle 10 has a traveling motor 14 (hereinafter referred to as “motor 14”) and an inverter 16 in addition to the power supply system 12.

The power supply system 12 includes a fuel cell unit 20 (hereinafter referred to as “FC unit 20”), a battery unit 22, and an integrated electronic control device 24 (hereinafter referred to as “integrated ECU 24”).

[A-1-2. Drive system]
The motor 14 of this embodiment is a three-phase AC brushless type. The motor 14 generates a driving force based on the electric power supplied from the FC unit 20 and the battery unit 22, and the driving force causes the wheels 32 to rotate through the transmission 30. Further, the motor 14 outputs the electric power (regenerative electric power Preg) [W] generated by the regeneration to the battery unit 22 or the like.

The inverter 16 has a three-phase full bridge type configuration and performs DC-AC conversion. More specifically, the inverter 16 converts the direct current into a three-phase alternating current and supplies it to the motor 14, while the direct current after the alternating current-DC conversion accompanying the regenerative operation is supplied to the battery 300 and the like through the battery converter 302 of the battery unit 22. Supply to. The motor 14 and the inverter 16 are collectively referred to as a load 40.

[A-1--3. FC unit 20]
(A-1-3-1. Outline of FC unit 20)
FIG. 2 is a schematic overall configuration diagram of the FC unit 20 of the present embodiment. As shown in FIGS. 1 and 2, the FC unit 20 includes a fuel cell stack 50 (hereinafter referred to as “FC stack 50”, “fuel cell 50” or “FC 50”), an FC monitoring unit 52, and an FC converter 54. And peripheral parts (not shown) of the FC stack 50.

(A-1--3-2. FC stack 50)
The FC stack 50 has, for example, a structure in which fuel cell cells formed by sandwiching a solid polymer electrolyte membrane between an anode electrode and a cathode electrode from both sides are laminated. The peripheral components include an anode system (not shown) that supplies and discharges hydrogen (fuel gas) to the anode of the FC stack 50, and air (oxidizing agent gas) containing oxygen to the cathode of the FC stack 50. A cathode system (not shown) for supplying and discharging is included.

(A-1--3-3. FC monitoring unit 52)
(A-1--3-3-1. Outline of FC monitoring unit 52)
The FC monitoring unit 52 (hereinafter, also referred to as “monitoring unit 52”) monitors the output of the FC stack 50. As shown in FIG. 2, the monitoring unit 52 includes an FC voltage sensor 70, a first FC current sensor 72, a second FC current sensor 74, a discharger 76, and an FC monitoring electronic control device 78 (hereinafter, “FC monitoring ECU 78””. Alternatively, it also has a "monitoring ECU 78"). Although not shown in FIG. 2, contactors may be provided on the positive electrode line 90 and the negative electrode line 92.

The FC voltage sensor 70 detects the output voltage from the FC stack 50 (hereinafter, referred to as “FC voltage Vfc”). The FC voltage sensor 70 is connected to the positive electrode line 90 and the negative electrode line 92 on the FC50 side of the discharger 76 (or the intersection 106 described later).

The first FC current sensor 72 detects the output current Ifc1 from the FC stack 50 (hereinafter, referred to as “first FC current Ifc1”). The first FC current sensor 72 is provided on the FC50 side of the positive electrode line 90 with respect to the discharger 76 (or the intersection 106 described later). The second FC current sensor 74 detects the input current Ifc2 (hereinafter, referred to as “second FC current Ifc2”) to the FC stack 50. The second FC current sensor 74 is provided on the FC50 side of the negative electrode line 92 with respect to the discharger 76 (or the intersection 108 described later).

The first FC current sensor 72 and the second FC current sensor 74 have a Hall element (not shown) as a detection element. For example, the first FC current sensor 72 detects the magnetic field of the current (first FC current Ifc1) flowing through the positive electrode line 90 and converts it into a voltage. Similarly, the second FC current sensor 74 detects the magnetic field of the current (second FC current Ifc2) flowing through the negative electrode line 92 and converts it into a voltage. Then, the currents corresponding to the detected voltages are output as the first FC current Ifc1 and the second FC current Ifc2. The second FC current sensor 74 of the present embodiment has higher detection accuracy than the second VCU current sensor 166, which will be described later.

The first FC current Ifc1 and the second FC current Ifc2 are used to manage the output of the FC stack 50. For example, it is used to estimate the amount of water produced during power generation in the FC stack 50. The FC stack 50 secures output performance and durability by wetting the electrolyte membrane with water generated during power generation. In order to prevent the FC stack 50 from becoming over-dried or over-humidified, it is necessary to appropriately manage the amount of reaction gas supplied to the FC stack 50. Therefore, it is important to control the amount of generated water. Further, in the present embodiment, the second FC current Ifc2 is also used for the zero point correction and the output map correction of the second VCU current Ivcu2, which will be described later.

The discharger 76 consumes the electric power remaining in the FC 50 or the FC converter 54 when the FC 50 is stopped or the like. The discharger 76 has a discharge resistor 100 and a switching element 102. The discharge resistor 100 and the switching element 102 are provided on the bypass line 104 connecting the positive electrode line 90 and the negative electrode line 92. The switching element 102 is turned on and off by a command (drive signal) from the monitoring ECU 78. Hereinafter, the intersection of the positive electrode line 90 and the bypass line 104 is referred to as an intersection 106, and the intersection of the negative electrode line 92 and the bypass line 104 is referred to as an intersection 108.

(A-1--3-2. FC monitoring ECU 78)
The FC monitoring ECU 78 is a computer that monitors or controls the input / output of the FC50. As shown in FIG. 2, the monitoring ECU 78 has an input / output unit 120, a calculation unit 122, and a storage unit 124.

The input / output unit 120 performs input / output with devices other than the monitoring ECU 78 (sensors 70, 72, 74, FC converter electronic control device 168, etc., which will be described later) (note that signal lines are omitted in FIG. 2). I want to be.). The input / output unit 120 includes an A / D conversion circuit (not shown) that converts the input analog signal into a digital signal.

The arithmetic unit 122 includes, for example, a central processing unit (CPU). The calculation unit 122 performs calculation based on signals from the sensors 70, 72, 74, the FC converter electronic control device 168, and the like. Then, the calculation unit 122 generates a signal for the discharger 76 and the like based on the calculation result.

As shown in FIG. 2, the calculation unit 122 includes a discharge control unit 130 and a failure diagnosis unit 132. The discharge control unit 130 and the failure diagnosis unit 132 are realized by executing the program stored in the storage unit 124. The program may be supplied from an external device via a communication device (not shown). A part of the program may be composed of hardware (circuit parts). As will be described later, the failure diagnosis unit 132 may be provided in the FC converter electronic control device 168 of the FC converter 54.

The discharge control unit 130 executes discharge control for discharging by using the discharger 76 when the FC50 is stopped or the like. The failure diagnosis unit 132 executes failure diagnosis control for diagnosing a failure in the FC unit 20. Details of the failure diagnosis control will be described later with reference to FIGS. 3 and 4.

The storage unit 124 stores programs and data used by the calculation unit 122. The storage unit 124 includes, for example, a random access memory (hereinafter referred to as “RAM”). As the RAM, a volatile memory such as a register and a non-volatile memory such as a flash memory can be used. Further, the storage unit 124 may have a read-only memory (hereinafter referred to as “ROM”) and / or a solid state drive (hereinafter referred to as “SSD”) in addition to the RAM.

(A-1--3-4. FC converter 54)
(A-1--4-1-1. Outline of FC converter 54)
The FC converter 54 is a boost chopper type voltage converter (DC / DC converter) that boosts the output voltage (FC voltage Vfc) of the FC 50 or supplies it to the inverter 16 or the battery unit 22 in a directly connected state. The FC converter 54 is arranged between the FC 50 and the inverter 16. In other words, one of the FC converters 54 is connected to the primary side 1Sf (FIG. 1) where the FC50 is located, and the other is connected to the secondary side 2S which is the connection point between the battery unit 22 and the load 40. Hereinafter, the FC converter 54 is also referred to as a converter 54, a boost converter 54 or an FC-VCU 54. FC-VCU54 means a voltage control unit for FC50.

As shown in FIG. 2, the FC-VCU 54 includes an inductor 150, a switching element 152, a diode 154, a smoothing capacitor 156, 158, a first VCU voltage sensor 160, a second VCU voltage sensor 162, and a first VCU current sensor. 164, a second VCU current sensor 166, and an FC converter electronic control device 168 (hereinafter referred to as "FC converter ECU 168" or "converter ECU 168") are provided. The FC-VCU 54 boosts the FC voltage Vfc by switching (duty control) the switching element 152 based on a command from the integrated ECU 24.

The inductor 150 and the diode 154 are provided on the positive electrode line 170. The switching element 152 is provided on the bypass line 174 connecting the positive electrode line 170 and the negative electrode line 172. In the following, the intersection of the positive electrode line 170 and the bypass line 174 is referred to as an intersection 176, and the intersection of the negative electrode line 172 and the bypass line 174 is referred to as an intersection 178. The inductor 150 is arranged closer to the FC50 than the intersection 176, and the diode 154 is arranged closer to the motor 14 than the intersection 176.

The first VCU voltage sensor 160 detects an input voltage from the FC stack 50 to the FC converter 54 (hereinafter, referred to as “first VCU voltage Vvcu1” or “VCU input voltage Vvcu1”). The first VCU voltage sensor 160 is connected to the positive electrode line 170 and the negative electrode line 172 on the FC50 side of the inductor 150 and the switching element 152. The second VCU voltage sensor 162 detects the output voltage of the FC converter 54 (hereinafter, referred to as “second VCU voltage Vvcu2” or “converter output voltage Vvcu2”). The second VCU voltage sensor 162 is connected to the positive electrode line 170 and the negative electrode line 172 on the load 40 side of the inductor 150 and the switching element 152.

The first VCU current sensor 164 is arranged on the positive electrode line 170 (particularly between the inductor 150 and the intersection 176) and detects the current Ivcu1 of the positive electrode line 170 (hereinafter, referred to as “first VCU current Ivcu1”). The second VCU current sensor 166 is arranged on the negative electrode line 172 (particularly between the smoothing capacitor 156 and the intersection 178) and detects the current Ivcu2 (hereinafter, referred to as “second VCU current Ivcu2”) of the negative electrode line 172.

The first VCU current sensor 164 and the second VCU current sensor 166 have a Hall element (not shown) as a detection element. For example, the first VCU current sensor 164 detects the magnetic field of the current (first VCU current Ivcu1) flowing through the positive electrode line 170 and converts it into a voltage. Similarly, the second VCU current sensor 166 detects the magnetic field of the current (second VCU current Ivcu2) flowing through the negative electrode line 172 and converts it into a voltage. Then, the currents corresponding to the detected voltages are output as the first VCU current Ivcu1 and the second VCU current Ivcu2. The second VCU current sensor 166 of the present embodiment has lower detection accuracy than the second FC current sensor 74.

(A-1--3-4-2. FC converter ECU 168)
The FC converter ECU 168 is a computer that controls conversion (here, boosting) of the output voltage Vfc of the FC50. As shown in FIG. 2, the converter ECU 168 has an input / output unit 180, a calculation unit 182, and a storage unit 184.

It should be noted that the input / output unit 180 performs input / output with devices other than the converter ECU 168 (sensors 160, 162, 164, 166, FC monitoring ECU 78, etc.) (Signal lines are omitted in FIG. 2). ). The input / output unit 180 includes an A / D conversion circuit (not shown) that converts the input analog signal into a digital signal.

The calculation unit 182 includes, for example, a CPU. The calculation unit 182 performs calculation based on signals from the sensors 160, 162, 164, 166, the FC monitoring ECU 78, and the like. Then, the calculation unit 182 generates a signal for the switching element 152 or the like based on the calculation result.

As shown in FIG. 2, the calculation unit 182 includes a zero point correction unit 190 and an output map correction unit 192. Both the correction units 190 and 192 are realized by executing the program stored in the storage unit 184. The program may be supplied from an external device via a communication device (not shown). A part of the program may be composed of hardware (circuit parts). As will be described later, the zero point correction unit 190 and the output map correction unit 192 may be provided in the FC monitoring ECU 78 of the FC monitoring unit 52.

The zero point correction unit 190 executes zero point learning control for performing zero point learning of the second VCU current sensor 166. Details of the zero point learning control will be described later with reference to FIG. The output map correction unit 192 defines a map 200 (hereinafter referred to as “output map 200” or “output map 200”) that defines the relationship between the voltage Vi2 output by the Hall element of the second VCU current sensor 166 and the current corresponding to this voltage (second VCU current Ivcu2). The output map correction control for correcting (also referred to as “Vi2-Ifc2 map 200”) is executed. Details of the output map correction control will be described later with reference to FIG.

The storage unit 184 stores programs and data used by the calculation unit 182. The storage unit 184 has, for example, a RAM, a ROM and / or an SSD.

[A-1-4. Battery unit 22]
As shown in FIG. 1, the battery unit 22 includes a high-voltage battery 300 (hereinafter, also referred to as “battery 300”) and a battery converter 302. The battery 300 is a power storage device (energy storage) including a plurality of battery cells, and for example, a lithium ion secondary battery, a nickel hydrogen secondary battery, or the like can be used. A power storage device such as a capacitor may be used instead of the battery 300.

The battery converter 302 is a step-up chopper type voltage converter (DC / DC converter). That is, the battery converter 302 boosts the output voltage (battery voltage Vbat) of the battery 300 or supplies it to the inverter 16 in a directly connected state. Further, the battery converter 302 can supply the regenerative voltage of the motor 14 (hereinafter referred to as "regenerative voltage Vreg") or the FC voltage Vfc to the battery 300 in a directly connected state.

[A-1-5. Integrated ECU 24]
The integrated ECU 24 controls the motor 14, the inverter 16, the FC50, the FC monitoring unit 52, the FC converter 54, the battery 300, and the battery converter 302 via the communication line 310 (FIG. 1). At the time of the control, the integrated ECU 24 executes a program stored in a storage unit (not shown). Further, the integrated ECU 24 uses the detection values of various sensors such as voltage sensors 70, 160, 162, current sensors 72, 74, 164, and 166.

In addition to the above sensors, the various sensors here include an opening degree sensor 110 and a motor rotation speed sensor 112 (FIG. 1). The opening degree sensor 110 detects the opening degree θp of the accelerator pedal 114 (hereinafter, also referred to as “accelerator pedal opening degree θp”) [degree]. The motor rotation speed sensor 112 detects the rotation speed of the motor 14 (hereinafter referred to as "motor rotation speed Nmot" or "rotation speed Nmot") [rpm]. The integrated ECU 24 detects the vehicle speed V [km / h] of the FC vehicle 10 by using the rotation speed Nmot. Further, a main switch 116 (hereinafter referred to as "main SW116") is connected to the integrated ECU 24. The main SW116 switches whether or not power can be supplied from the FC50 and the battery 300 to the motor 14, and can be operated by the user.

The integrated ECU 24 is required of the power supply system 12 as a whole of the FC vehicle 10 based on the state of the FC stack 50, the state of the battery 300, the state of the motor 14, and the inputs (load requests) from various switches and various sensors. The load Psys (hereinafter referred to as "system load Psys") is determined. Then, the integrated ECU 24 determines the load to be borne by the FC stack 50, the load to be borne by the battery 300, and the load distribution (sharing) to be borne by the regenerative power source (motor 14) while arbitrating. Further, the integrated ECU 24 sends a command to the motor 14, the inverter 16, the FC50, the FC monitoring unit 52, the FC converter 54, the battery 300, and the battery converter 302.

<A-2. Control of this embodiment>
Next, the control of this embodiment will be described. As described above, in the present embodiment, discharge control, failure diagnosis control, zero point learning control, and output map correction control are executed as controls related to the power supply system 12. The discharge control is executed by the discharge control unit 130 of the FC monitoring ECU 78, and the failure diagnosis control is executed by the failure diagnosis unit 132 (diagnosis unit) of the FC monitoring ECU 78. The zero point learning control is executed by the zero point correction unit 190 of the FC converter ECU 168, and the output map correction control is executed by the output map correction unit 192.

[A-2-1. Discharge control]
When the integrated ECU 24 requests to stop the FC50, the discharge control unit 130 turns on the discharger 76 and consumes the power generated by the residual gas in the FC50. This makes it possible to suppress the deterioration of the FC50. Further, in the present embodiment, the discharger 76 is arranged between the FC50 and the FC converter 54. Therefore, it is possible to relax the performance requirements of the FC converter 54.

[A-2-2. Failure diagnosis control]
FIG. 3 is a flowchart of failure diagnosis control in this embodiment. FIG. 4 is a time chart showing various signals and values when the failure diagnosis control in the present embodiment is executed. Specifically, FIG. 4 shows a discharge command Cd for the discharger 76, a second FC current Ifc2 (first current) detected by the second FC current sensor 74 (first current sensor), and a second VCU current sensor 166 (third). 2 The second VCU current Ivcu2 (second current) detected by the current sensor) is shown. In the present embodiment, the FC monitoring ECU 78 executes the failure diagnosis control, but as will be described later, the FC converter ECU 168 may execute the failure diagnosis control.

Further, it should be noted that FIG. 4 shows a state in which an abnormality has occurred in the FC unit 20 as a whole. Further, in FIG. 4, the second FC current Ifc2 shown by the solid line after the time point t12 is a waveform when the discharger 76 is on-failed (the switching element 102 is closed and fixed). Furthermore, the second FC current Ifc2 shown by the broken line after the time point t12 is a waveform when the second FC current sensor 74 or the second VCU current sensor 166 is out of order.

The second FC current Ifc2 and the second VCU current Ivcu2 after the time point t11 are waveforms when the discharger 76 is on-failed or the second FC current sensor 74 or the second VCU current sensor 166 is failed. In FIG. 4, the second FC current Ifc2 and the second VCU current Ivcu2 are constant even after the time point t11, but when the second FC current sensor 74 or the second VCU current sensor 166 is out of order, the second FC current Ifc2 or the second VCU It is also conceivable that the current Ivcu2 decreases.

The failure diagnosis control is executed at predetermined intervals during the power generation of the FC50. Alternatively, failure diagnosis control may be performed at other timings. In step S11 of FIG. 3, the monitoring ECU 78 acquires the second FC current Ifc2 detected by the second FC current sensor 74 and the second VCU current Ivcu2 detected by the second VCU current sensor 166. In step S12, the monitoring ECU 78 determines whether or not the absolute value | ΔI | of the difference ΔI (hereinafter, also referred to as “current difference ΔI”) between the second FC current Ifc2 and the second VCU current Ivcu2 is equal to or greater than the first current difference threshold THΔI. To judge. The first current difference threshold value THΔI (hereinafter, also referred to as “threshold value THΔI”) is a threshold value for determining whether or not the current difference ΔI is an abnormal value.

When the absolute value of the current difference ΔI is equal to or greater than the threshold value THΔI (S12: TRUE), the current difference ΔI indicates an abnormal value. In that case, the process proceeds to step S13. When the absolute value of the current difference ΔI is not equal to or greater than the threshold value THΔI (S12: FALSE), the current difference ΔI indicates a normal value. In that case, the failure diagnosis control this time is ended, and the process returns to step S11 after a predetermined time has elapsed.

In step S13, the monitoring ECU 78 sets the second FC current Ifc2 acquired in step S11 as the reference current Iref. The reference current Iref is used in step S16 described later.

In step S14, the monitoring ECU 78 transmits an on command (discharge command Cd) to the discharger 76 (time point t12 in FIG. 4). Specifically, the monitoring ECU 78 transmits the drive signal S to the switching element 102 of the discharger 76. As a result, the switching element 102 is turned on.

Therefore, a part of the current from the FC 50 reaches the second FC current sensor 74 via the discharger 76. When the discharger 76 is not turned on, the FC current Ifc is increased by turning on the discharger 76. Therefore, when the discharger 76 is not on-failed , the second FC current Ifc2 detected by the second FC current sensor 74 increases as shown at the time point t12 in FIG.

In step S15 of FIG. 3, the monitoring ECU 78 acquires a new second FC current Ifc2 from the second FC current sensor 74.

In step S16, the monitoring ECU 78 determines whether or not the difference ΔIfc2 between the second FC current Ifc2 and the reference current Iref (hereinafter, also referred to as “second current difference ΔIfc2”) is equal to or less than the second current difference threshold THΔi2. The second current difference threshold value THΔi2 (hereinafter, also referred to as “threshold value THΔi2”) is a threshold value for determining the cause of the second current difference ΔIfc2 showing an abnormal value.

That is, when the second current difference ΔIfc2 is equal to or less than the threshold value THΔi2 (S16: TRUE), the monitoring ECU 78 determines that the discharger 76 is on-failed (or the switching element 102 is closed and fixed) in step S17. judge. This is because it can be estimated that the switching element 102 is not operating normally when the current change due to the diversion cannot be captured even if the command for turning on the switching element 102 is issued.

When the second current difference ΔIfc2 is not equal to or less than the threshold value THΔi2 (S16: FALSE), in step S18, the monitoring ECU 78 determines that the second FC current sensor 74 or the second VCU current sensor 166 is abnormal. When it is possible to capture the current change due to the diversion by issuing the command for turning on the switching element 102, it can be determined that the switching element 102 is operating normally. Therefore, the current difference ΔI (difference) between the second FC current Ifc2 and the second VCU current Ivcu2 can be estimated to be due to the second FC current sensor 74 or the second VCU current sensor 166.

After step S17 or S18, in step S19, the monitoring ECU 78 performs error processing. For example, the monitoring ECU 78 causes a display unit (not shown) to display a warning message indicating the content of the abnormality. Further, the monitoring ECU 78 may store a failure code indicating the content of the abnormality in the storage unit 124.

[A-2-3. Zero point learning control]
FIG. 5 is a flowchart of zero point learning control in this embodiment. As described above, the zero point learning control is a process of learning the zero point of the second VCU current sensor 166, which has a relatively low detection accuracy, using the zero point of the second FC current sensor 74, which has a relatively high detection accuracy. is there. The zero point learning control is executed, for example, immediately after the FC50 starts to start. The zero point learning process may be performed at other timings. In the present embodiment, the FC converter ECU 168 executes the zero point learning control, but as will be described later, the FC monitoring ECU 78 may execute the zero point learning control.

In step S31 of FIG. 5, the converter ECU 168 determines whether or not the discharger 76 is off. For example, the zero point correction unit 190 of the converter ECU 168 determines whether or not the discharger 76 is off depending on whether or not the FC monitoring ECU 78 outputs an on signal (drive signal S) to the discharger 76. To judge. If the discharger 76 is off (S31: TRUE), the process proceeds to step S32. When the discharger 76 is not turned off (S31: FALSE), the zero point correction of the second VCU current sensor 166 is not performed. Therefore, the zero point learning control this time is ended, and the process returns to step S31 after the elapse of a predetermined time.

In step S32, the converter ECU 168 acquires the VCU input voltage Vvcu1 from the monitoring ECU 78 from the first VCU voltage sensor 160. In step S33, the converter ECU 168 determines whether or not the VCU input voltage Vvcu1 is equal to or less than the first voltage threshold value THv1. The first voltage threshold value THv1 is a threshold value for confirming that the VCU input voltage Vvcu1 is in a relatively low state. When the VCU input voltage Vvcu1 is equal to or less than the first voltage threshold value THv1 (S33: TRUE), the process proceeds to step S34. When the VCU input voltage Vvcu1 is not equal to or less than the first voltage threshold value THv1 (S33: FALSE), the current zero point learning control is terminated. Then, when the condition for executing the new zero point learning control is satisfied, the process returns to step S31.

In addition to or instead of determining whether the VCU input voltage Vvcu1 is equal to or less than the first voltage threshold value THv1, whether or not the amount of change in the VCU input voltage Vvcu1 per unit time is equal to or less than the change amount threshold value. May be determined. This makes it possible to perform zero point correction in a state where the VCU input voltage Vvcu1 is stable.

In step S34, the converter ECU 168 acquires the second FC current Ifc2 detected by the second FC current sensor 74. In step S35, the converter ECU 168 determines whether or not the second FC current Ifc2 is zero (or the origin). When the second FC current Ifc2 is zero (S35: TRUE), the process proceeds to step S36. When the second FC current Ifc2 is not zero (S36: FALSE), the current zero point learning control is terminated. Then, when the condition for executing the new zero point learning control is satisfied, the process returns to step S31.

In step S36, the converter ECU 168 corrects (or resets) the zero point of the second VCU current sensor 166 in accordance with the zero point of the second FC current sensor 74.

[A-2-4. Output map correction control]
FIG. 6 is a flowchart of the output map correction control in the present embodiment. FIG. 7 is a diagram showing the current-voltage characteristics of the FC stack 50 in this embodiment. As described above, the output map correction control (hereinafter, also referred to as “map correction control”) corrects the output map 200 stored in the storage unit 184 of the converter ECU 168. The map correction control is executed at predetermined intervals, for example, during the power generation of the FC50. Alternatively, the map correction control may be executed at other timings. In the present embodiment, the FC converter ECU 168 executes the output map correction control, but as will be described later, the FC monitoring ECU 78 may execute the output map correction control.

In step S51, the converter ECU 168 acquires the VCU input voltage Vvcu1 from the first VCU voltage sensor 160. In step S52, the converter ECU 168 determines whether or not the VCU input voltage Vvcu1 is equal to or higher than the second voltage threshold value THv2. The second voltage threshold value THv2 is a threshold value for confirming that the discharger 76 is not stuck on.

That is, as shown in FIG. 7, the FC stack 50 of the present embodiment has a characteristic that the FC voltage Vfc decreases as the FC current Ifc increases. When the discharger 76 is fixed on, the FC current Ifc increases significantly and the FC voltage Vfc decreases. Therefore, by confirming that the VCU input voltage Vvcu1 corresponding to the FC voltage Vfc is high, it is possible to confirm that the discharger 76 is not fixed on. Instead of the VCU input voltage Vvcu1, the FC voltage Vfc detected by the FC voltage sensor 70 may be used.

When the VCU input voltage Vvcu1 is equal to or higher than the second voltage threshold value THv2 (S52: TRUE), the discharger 76 is not stuck on. In that case, the process proceeds to step S53. When the VCU input voltage Vvcu1 is not equal to or higher than the second voltage threshold value THv2 (S52: FALSE), it is difficult to determine whether or not the discharger 76 is stuck on. In that case, the map correction control this time is ended, and the process returns to step S51 after a predetermined time has elapsed.

In step S53, the converter ECU 168 acquires the second FC current Ifc2 detected by the second FC current sensor 74 from the monitoring ECU 78. In step S54, the converter ECU 168 acquires the voltage Vi2 detected by the Hall element of the second VCU current sensor 166. As described above, the second VCU current sensor 166 includes a Hall element, and the output map 200 defines the relationship between the voltage value (that is, the voltage Vi2) of the Hall element and the second VCU current Ivcu2.

In step S55, the converter ECU 168 updates the Vi2-Ivcu2 map for the second VCU current sensor 166. That is, the value of the second FC current Ifc2 is rewritten as the second VCU current Ivcu2 corresponding to the voltage Vi2 in the map 200.

As described above, the second FC current sensor 74 has higher accuracy than the second VCU current sensor 166. Therefore, by rewriting the map 200 as described above, the second VCU current Ivcu2 used by the converter ECU 168 becomes highly accurate.

<A-3. Effect of this embodiment>
As described above, according to the present embodiment, the second FC current Ifc2 (first current) in the negative electrode line 92 on the FC stack 50 (power supply) side of the discharge resistor 100 and the load 40 of the discharge resistor 100 When it is determined that the second VCU current Ivcu2 (second current) in the negative electrode line 172 on the side is different (S12: TRUE in FIG. 3), the switching element 102 is turned on in order to start the discharge by the discharge resistor 100. Is issued (S14 in FIG. 3, t12 in FIG. 4). Then, the failure portion is estimated based on the change in the second FC current Ifc2 before and after the command for turning on the switching element 102 is issued (S16 to S18 in FIG. 3). Therefore, it is possible to estimate the faulty part by a simple method.

In the present embodiment, when the second FC current Ifc2 (first current) changes before and after the command for turning on the switching element 102 is issued (S16: FALSE in FIG. 3), the failure diagnosis unit 132 , It is estimated that at least one of the second FC current sensor 74 (first current acquisition means) and the second VCU current sensor 166 (second current acquisition means) has failed (S18).

This makes it possible to detect a failure of the second FC current sensor 74 or the second VCU current sensor 166 by a simple method. Further, if the second FC current sensor 74 or the second VCU current sensor 166 fails, the control using the second FC current Ifc2 and the second VCU current Ivcu2 (for example, zero point learning control, output map correction control, etc.) cannot be properly performed. According to the present embodiment, since the failure of the second FC current sensor 74 or the second VCU current sensor 166 can be detected, it is possible to easily detect a situation in which control using the second FC current Ifc2 and the second VCU current Ivcu2 is not properly performed. It becomes possible to do.

In the present embodiment, when the second FC current Ifc2 (first current) has the same value before and after the command for turning on the switching element 102 is issued (S16: TRUE in FIG. 3), the failure diagnosis unit 132. Estimates that the discharger 76 is on-failed (the switching element 102 (switch) is closed and fixed) (S17).

This makes it possible to detect the closing and sticking of the switching element 102 by a simple method. Further, when the switching element 102 arranged in series with the discharge resistor 100 is closed and fixed, the second FC current sensor 74 and the second VCU current sensor 166 have the second FC current Ifc2 and the second VCU as erroneous values that should not be originally present. The current Ivcu2 will be detected. In that case, the control using the second FC current Ifc2 and the second VCU current Ivcu2 (for example, zero point learning control, output map correction control, etc.) is not properly performed. According to the present embodiment, since the closing and sticking of the switching element 102 can be detected, it is possible to easily detect a situation in which control using the second FC current Ifc2 and the second VCU current Ivcu2 is not properly performed. Further, when it is determined that the second FC current Ifc2 and the second VCU current Ivcu2 are different, a command for turning on the switching element 102 is issued, and the second FC current Ifc2 changes before and after the command is issued. When identifying the cause location according to the same or the same, it is possible to take appropriate fail-safe measures.

In the present embodiment, the power supply system 12 includes a zero point correction unit 190 (zero point learning means) that executes zero point learning control for learning the zero point of the second VCU current sensor 166 (second current acquisition means) (FIG. 2). In the zero point correction unit 190, the switching element 102 (switch) is instructed to open (S31: TRUE in FIG. 5), and the VCU input voltage Vvcu1 corresponding to the output voltage Vfc of the FC50 is the first voltage threshold THv1. The following (S33: TRUE) is set as an execution condition of the zero point learning control. As a result, the zero point learning of the second VCU current sensor 166 can be performed when the conditions suitable for the zero point learning are satisfied.

In the present embodiment, the power supply system 12 uses the second VCU current of the second VCU current sensor 166 (second current acquisition means) based on the second FC current Ifc2 (acquired value) of the second FC current sensor 74 (first current acquisition means). An output map correction unit 192 (acquisition value correction means) that executes an output map correction control (acquisition value correction control) for correcting Ivcu2 (acquisition value) is provided (FIG. 2). The output map correction unit 192 sets that the VCU input voltage Vvcu1 corresponding to the output voltage Vfc of the FC50 is equal to or higher than the second voltage threshold value THv2 (S52: TRUE in FIG. 6) as an execution condition of the output map correction control. This makes it possible to correct the acquired value of the second VCU current sensor 166 when conditions suitable for the correction of the output map 200 are satisfied.

B. Modifications It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various configurations can be adopted based on the contents described in the present specification. For example, the following configuration can be adopted.

<B-1. Installation target>
In the above embodiment, the power supply system 12 is mounted on the FC vehicle 10 (FIG. 1). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, the power supply system 12 can be used for moving objects such as ships and aircraft. Alternatively, the power supply system 12 may be applied to robots, manufacturing equipment, household electric power systems or home appliances.

<B-2. Configuration of power supply system 12>
In the above embodiment, the FC converter 54 is used as a boost converter (FIG. 2). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, the FC converter 54 can be a buck-boost converter capable of stepping up and down the FC voltage Vfc, or a step-down converter capable of stepping down the FC voltage Vfc.

The power supply system 12 of the above embodiment has both the FC unit 20 and the battery unit 22 (FIG. 1). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, the battery unit 22 can be omitted.

In the above embodiment, the motor 14 is an AC type (FIG. 1). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, the motor 14 can be of a direct current type. In this case, the inverter 16 can be omitted.

In the above embodiment, the motor 14 is used for traveling or driving the FC vehicle 10 (FIG. 1). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, the motor 14 may be used for in-vehicle equipment (for example, electric power steering, air compressor, air conditioner).

In the above embodiment, the second FC current Ifc2 and the second VCU current sensor 166 are set as the targets of the failure diagnosis (FIGS. 3 and 4). However, for example, when it is determined that the first current in the negative electrode line on the FC50 (power supply) side of the discharge resistor 100 and the second current in the negative electrode line on the load 40 side of the discharge resistor 100 are different, switching is performed. From the viewpoint of estimating the failure site based on the change in the first current before and after the command for turning on the element 102 is issued, the present invention is not limited to this. For example, in a configuration in which the battery unit 22 and the FC converter 54 are not provided, when a current sensor (inverter current sensor) is provided in the negative electrode line between the FC monitoring unit 52 and the inverter 16, the second FC current sensor 74 and the inverter current sensor are used. It can be the target of failure diagnosis.

In the above embodiment, the monitoring ECU 78 and the converter ECU 168 are provided as the control main body of the FC unit 20 (FIG. 2). However, for example, it is also possible to combine both to form one ECU. Alternatively, the functions of the monitoring ECU 78 and the converter ECU 168 can be incorporated into the integrated ECU 24.

Although the current sensors 72, 72, 164, and 166 of the above embodiment have Hall elements, other types of current sensors may be used.

<B-3. Control of power supply system 12>
[B-3-1. General]
In the above embodiment, failure diagnosis control (FIG. 3), zero point learning control (FIG. 5), and output map correction control (FIG. 6) are executed. However, for example, focusing on each control, the power supply system 12 can perform any one or two controls.

In the above embodiment, the FC unit 20 executes failure diagnosis control (FIG. 3), zero point learning control (FIG. 5), and output map correction control (FIG. 6). However, for example, when it is determined that the first current in the negative electrode line on the power supply side of the discharge resistor 100 and the second current in the negative electrode line on the load 40 side of the discharge resistor 100 are different, the switching element 102 is used. From the viewpoint of estimating the failure site based on the change in the first current before and after the command for turning on is issued, the present invention is not limited to this. For example, failure diagnosis control, zero point learning control, or output map correction control can be performed by the battery unit 22.

[B-3-2. Failure diagnosis control (Fig. 3)]
In the above embodiment, the failure diagnosis unit 132 is provided in the monitoring ECU 78. In other words, the monitoring ECU 78 executed the failure diagnosis control. However, for example, from the viewpoint of one ECU executing the failure diagnosis control, the zero point learning control, and the output map correction control, the converter ECU 168 may execute the failure diagnosis control. In that case, the detection value and the state of the control target (second FC current sensor 74, discharger 76, etc.) on the monitoring ECU 78 side are inquired from the converter ECU 168 to the monitoring ECU 78.

In the failure diagnosis control of the above embodiment, when the absolute value of the current difference ΔI between the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) becomes equal to or greater than the first current difference threshold THΔI, an abnormality occurs. It was determined that the current occurred (S12 in FIG. 3). However, for example, when it is determined that the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) are different, before and after the command for turning on the switching element 102 is issued. From the viewpoint of estimating the failure site based on the change in the second FC current Ifc2, the present invention is not limited to this. For example, when the change rate difference between the change amount of the second FC current Ifc2 per unit time and the change amount of the second VCU current Ivcu2 per unit time is equal to or more than the speed difference threshold value, it is determined that an abnormality has occurred. It is also possible to do.

In the failure diagnosis control of the above embodiment, the presence or absence of an abnormality is determined by comparing the second FC current Ifc2 (first current) and the second VCU current Ivcu2 (second current) (S12 in FIG. 3). However, for example, in comparison between the first energized state amount on the FC50 (power supply) side of the discharger 76 or the discharge resistor 100 and the second energized state amount on the load 40 side of the discharger 76 or the discharge resistor 100. Based on this, from the viewpoint of determining an abnormality in the FC unit 20 or the power supply system 12, the present invention is not limited to this.

For example, the abnormality of the FC unit 20 or the power supply system 12 is determined based on the comparison between the FC voltage Vfc detected by the FC voltage sensor 70 (FIG. 2) and the first VCU voltage Vvcu1 detected by the first VCU voltage sensor 160. Is also possible. Alternatively, the abnormality of the FC unit 20 or the power supply system 12 is determined based on the comparison between the product (electric power) of the second FC current Ifc2 and the FC voltage Vfc and the product (electric power) of the second VCU current Ivcu2 and the first VCU voltage Vvcu1. It is also possible.

In the failure diagnosis control of the above embodiment, when step S12 in FIG. 3 is “true” (TRUE), the discharger 76 is turned on and the failure site is narrowed down by the change in the second FC current Ifc2 (S16 to S16 in FIG. 3). S18). However, for example, a change in the first energized state amount (the energized state amount on the FC50 (power supply) side of the discharger 76 or the discharge resistor 100) or the second energized state amount (the energized state amount on the FC50 (power supply) side of the discharger 76 or the discharge resistor 100) due to turning on the discharger 76 From the viewpoint of narrowing down the failure site based on the change in the energization state amount on the load 40 side of the discharger 76 or the discharge resistor 100), the present invention is not limited to this.

For example, based on the change in the FC voltage Vfc (first energized state amount) detected by the FC voltage sensor 70 or the change in the first FC current Ifc1 (first energized state amount) detected by the first FC current sensor 72, the faulty part is determined. It is also possible to narrow down. In the FC50, the output current changes according to the output voltage, and the output voltage changes according to the output current (FIG. 7). Therefore, when the discharger 76 is turned on and the resistance of the entire FC unit 20 changes, the FC voltage Vfc or the first FC current Ifc1 changes. Therefore, by confirming the presence or absence of a change in the FC voltage Vfc or the first FC current Ifc1, it is possible to confirm the presence or absence of an ON failure (closed fixation) of the discharger 76.

Alternatively, it is also possible to narrow down the faulty part based on the change in the second VCU current Ivcu2 (second energized state amount) detected by the second VCU current sensor 166. Alternatively, it is also possible to narrow down the faulty part based on the change in the first VCU voltage Vvcu1 (second energized state amount) detected by the first VCU voltage sensor 160. Alternatively, it is also possible to narrow down the faulty part based on the change in the product (electric power) (second energized state amount) of the second FC current Ifc2 and the first VCU voltage Vvcu1.

[B-3-3. Zero point learning control (Fig. 5)]
In the zero point learning control of the above embodiment, the zero point of the second FC current Ifc2, which is the detection value of the second FC current sensor 74, is set as the zero point of the second VCU current sensor 166 (FIG. 5). However, for example, when the detection accuracy of the second VCU current sensor 166 is higher than that of the second FC current sensor 74, the zero point of the second VCU current sensor 166 can be used as the zero point of the second FC current sensor 74. ..

[B-3-4. Output map correction control (Fig. 6)]
In the output map correction control of the above embodiment, the second FC current Ifc2, which is a detected value of the second FC current sensor 74, is used to correct the output map 200 of the second VCU current sensor 166 (FIG. 6). However, for example, when the detection accuracy of the second VCU current sensor 166 is higher than that of the second FC current sensor 74, the second VCU current Ivcu2, which is the detection value of the second VCU current sensor 166, is used in the output map of the second FC current sensor 74. It can also be used for correction.

12 ... Power supply system 40 ... Load 50 ... FC stack (power supply)
74 ... Second FC current sensor (first current acquisition means)
92 ... Negative electrode line 100 on the power supply side of the discharge resistor ... Discharge resistor 102 ... Switching element (switch)
132 ... Failure diagnosis department (diagnosis department)
166 ... Second VCU current sensor (second current acquisition means)
172 ... Negative electrode line 190 on the load side of the discharge resistor ... Zero point correction unit (zero point learning means)
192 ... Output map correction unit (acquisition value correction means)
Ifc2 ... 2nd FC current (1st current)
Ivcu2 ... 2nd VCU current (2nd current)
THv1 ... 1st voltage threshold THv2 ... 2nd voltage threshold Vfc ... FC output voltage

Claims (5)

Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first current acquisition means for acquiring a first current in the negative electrode line on the power supply side of the discharge resistor, and
A power supply system including a second current acquisition means for acquiring a second current in the negative electrode line on the load side of the discharge resistor.
The power supply system further comprises a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first current and the second current are different, it issues a command to turn on the switch, and the first current is generated before and after the command is issued. If the values are the same, it is presumed that the switch is closed and fixed, and if the first current changes before and after the command is issued, the first current acquisition means and the second current acquisition means A power supply system characterized in that at least one is presumed to be out of order. In the power supply system according to claim 1,
The power source is a fuel cell
The power supply system includes zero point learning means for executing zero point learning control for learning the zero point of the first current acquisition means or the second current acquisition means.
The zero point learning means sets as the execution conditions of the zero point learning control that an open command is given to the switch and that the output voltage of the fuel cell is equal to or less than the first voltage threshold value or does not fluctuate. A power supply system characterized by In the power supply system according to claim 1,
The power source is a fuel cell
The power supply system includes acquisition value correction means for executing acquisition value correction control for correcting the acquisition value of the other based on the acquisition value of one of the first current acquisition means and the second current acquisition means.
The power supply system characterized in that the acquired value correction means sets that the output voltage of the fuel cell is equal to or higher than the second voltage threshold value as an execution condition of the acquired value correction control. Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first current acquisition means for acquiring a first current in the negative electrode line on the power supply side of the discharge resistor, and
A second current acquisition means for acquiring a second current in the negative electrode line on the load side of the discharge resistor, and
It is a control method of a power supply system equipped with a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first current and the second current are different, it issues a command to turn on the switch, and the first current is generated before and after the command is issued. If the values are the same, it is presumed that the switch is closed and fixed, and if the first current changes before and after the command is issued, the first current acquisition means and the second current acquisition means A method of controlling a power system, characterized in that at least one is presumed to be out of order. Power supply and
The load to which power is supplied from the power source and
A discharge resistor connected in parallel with the load to the power supply between the power supply and the load.
A switch connected in series with the discharge resistor,
A first energized state amount acquisition means for acquiring a first energized state amount on the power supply side of the discharge resistor, and
A power supply system including a second energized state amount acquisition means for acquiring a second energized state amount on the load side of the discharge resistor.
The power supply system further comprises a diagnostic unit for diagnosing a failure in the power supply system.
When the diagnostic unit determines that the first energized state amount and the second energized state amount are different, it issues a command for turning on the switch, and the command is issued before and after the command is issued. When the first energized state amount is the same value, it is estimated that the switch is closed and fixed, and when the first energized state amount changes before and after the command is issued, the first energized state amount A power supply system characterized in that at least one of the acquisition means and the second energization state quantity acquisition means is presumed to be out of order.

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