Power supply control device, power supply control method, and non-transitory computer-readable recording medium having a power supply control program recorded thereon

Abstract

The present disclosure relates to a power supply control device, a power supply control method, and a non-transitory computer-readable recording medium recording a power supply control program. The power supply control device includes: a cut-off relay that turns on or cuts off between a first terminal of a load and a first pole of a direct current power supply; a dark current generation circuit that generates a dark current by dropping a voltage of the direct current power supply in a state where the first terminal is connected to the first pole of the direct current power supply and a second terminal is connected to the first terminal of the load in a manner that the cut-off relay is in parallel; and a bypass circuit that, in a case where the direct current power supply is charged by an external charger, turns on a second pole of the direct current power supply and the first terminal of the load to consume a part of power supplied from the external charger.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a power supply control device, a power supply control method, and a non-transitory computer-readable recording medium having a power supply control program recorded thereon. BACKGROUND

[0002] Sometimes, in order to perform protection of a circuit including a vehicle-mounted power supply such as a secondary battery, a cut-off relay is provided between the power supply and a load, and the cut-off relay diagnoses an operating condition at the time of engine start of a vehicle or the like.

[0003] In International Publication No. 16 / 103721, an invention of a power supply protection device, a power supply device, and a switching failure diagnosis method that diagnoses opening and closing of a cut-off relay based on a voltage change of a circuit is disclosed. SUMMARY

[0004] PROBLEMS TO BE SOLVED BY THE INVENTION

[0005] However, in International Publication No. 16 / 103721, when an external charger is connected to the power supply, the voltage of the circuit does not decrease, and thus it becomes difficult to determine whether the opening and closing of the cut-off relay is properly performed.

[0006] An object of the present disclosure is to obtain a power supply control device, a power supply control method, and a non-transitory computer-readable recording medium having a power supply control program recorded thereon, which can perform operating diagnosis of a cut-off relay even in a state where an external charger is connected.

[0007] METHOD FOR SOLVING THE PROBLEMS

[0008] The first aspect is a power supply control device including: a cut-off relay that turns on or off between a first terminal of a load and a first pole of a direct current power supply; a dark current generation circuit that generates a dark current by decreasing a voltage of the direct current power supply in a state where the first terminal is connected to the first pole of the direct current power supply and a second terminal is connected to the first terminal of the load in a manner that the cut-off relay is in parallel; and a bypass circuit that, in a case where the direct current power supply is charged by an external charger, turns on a second pole of the direct current power supply and the first terminal of the load to consume a part of power supplied from the external charger.

[0009] According to the power supply control device of the first aspect, by consuming a part of power supplied from the external charger by the bypass circuit, operating diagnosis of the first switcher, which is the cut-off relay, can be performed even in a state where the external charger is connected.

[0010] The power supply control device of the second aspect is the power supply control device of the first aspect, further comprising: a memory; and a processor connected to the memory, the processor configured to detect a potential difference between the second terminal and the first terminal of the dark current generation circuit, detect a current between the second terminal of the load and the second pole of the DC power supply, control conduction or interruption of the cut-off relay, and determine a state of the cut-off relay based on the detected potential difference and the detected current.

[0011] The power supply control device of the second aspect is the power supply control device of the first aspect, further comprising: a memory; and a processor connected to the memory, the processor configured to detect a potential difference between the second terminal and the first terminal of the dark current generation circuit, detect a current between the second terminal of the load and the second pole of the DC power supply, control conduction or interruption of the cut-off relay, and determine a state of the cut-off relay based on the detected potential difference and the detected current.

[0012] The power supply control device of the third aspect is the power supply control device of the second aspect, wherein the processor is configured to determine that the cut-off relay is in an open state when the detected potential difference is equal to or greater than a predetermined threshold voltage.

[0013] The power supply control device of the fourth aspect is the power supply control device of the second aspect, wherein the processor is configured to determine that the cut-off relay is stuck in a closed state when the detected potential difference is less than a predetermined threshold voltage and the detected current is equal to or greater than a predetermined threshold current.

[0014] The power supply control device of the fifth aspect is the power supply control device of the second aspect, wherein the bypass circuit includes a switch that controls conduction or interruption between the first terminal of the load and the second pole of the DC power supply, and a resistor that dissipates a portion of the conducted power, and the processor is configured to connect the second pole of the DC power supply to the first terminal of the load by controlling the switch to be on when the detected potential difference is less than a predetermined threshold voltage and the detected current is less than a predetermined threshold current.

[0015] The power supply control device of the sixth aspect is the power supply control device of the fifth aspect, wherein the processor is configured to determine that charging of the DC power supply by the external charger is in progress when the detected current is equal to or greater than a predetermined threshold current in a state in which the bypass circuit connects the second pole of the DC power supply to the first terminal of the load.

[0016] The seventh power control device is, in the fifth power control device, wherein the processor is configured to determine that the current-cutting relay is in an open circuit state when the current detected is less than a predetermined threshold current and the detected potential difference is greater than a predetermined threshold voltage when the bypass circuit conducts between the second pole of the DC power supply and the first terminal of the load.

[0017] The power control device of the eighth method is, in the power control device of the fifth method, the processor is configured to determine that the current-cutting relay is stuck in the closed state when the current detected is less than a predetermined threshold current and the potential difference detected is less than a predetermined threshold voltage when the bypass circuit conducts the second pole of the DC power supply and the first terminal of the load.

[0018] The ninth method is a power control method that uses a processor to perform the following processing: detecting the potential difference between the second and first terminals of a dark current generation circuit; wherein the dark current generation circuit is configured such that its first terminal is connected to the first terminal of the DC power supply and its second terminal is connected to the first terminal of the load, in a state where it is connected in parallel with a current-cutting relay that controls the conduction or cutoff between the first terminal of the load and the first terminal of the DC power supply; causing the voltage of the DC power supply to drop and generating a dark current; detecting the current between the second terminal of the load and the second terminal of the DC power supply; and determining the state of the current-cutting relay based on the potential difference and the current; and determining the state of the current-cutting relay when the potential difference is small. When a predetermined threshold voltage is reached and the current is less than a predetermined threshold current, the bypass circuit is turned on. In this state, the bypass circuit depletes a portion of the power supplied by the external charger while the second terminal of the DC power supply is connected to the first terminal of the load. The state of the current-cutting relay and the presence or absence of charging of the DC power supply by the external charger are determined based on the potential difference between the second and first terminals of the dark current generation circuit and the current between the second terminal of the load and the second terminal of the DC power supply, which are detected when the second terminal of the DC power supply and the first terminal of the load are connected through the bypass circuit.

[0019] According to the power control method of the ninth method, by utilizing a bypass circuit to deplete a portion of the power supplied from the external charger, it is possible to perform operational diagnostics as the first switching unit of the current-cutting relay even when the external charger is connected.

[0020] The tenth aspect is a non-transitory computer-readable recording medium storing a program for causing a computer to execute a process of determining a state of a cut-off relay based on a potential difference between a second terminal and a first terminal of a dark current generation circuit and a current between a second terminal of a load and a second pole of a direct current power supply, wherein the dark current generation circuit generates a dark current by dropping a voltage of the direct current power supply in a state in which the first terminal is connected to the first pole of the direct current power supply and the second terminal is connected to a first terminal of the load in a manner in which the cut-off relay that turns on or off between the first terminal of the load and the first pole of the direct current power supply is connected in parallel, and controlling a bypass circuit to an on state in a case where the potential difference is less than a predetermined threshold voltage and the current is less than a predetermined threshold current, wherein the bypass circuit consumes a part of power supplied from an external charger in a state in which the second pole of the direct current power supply and the first terminal of the load are turned on, and determines the state of the cut-off relay and whether or not charging of the direct current power supply by the external charger is performed based on the potential difference between the second terminal and the first terminal of the dark current generation circuit and the current between the second terminal of the load and the second pole of the direct current power supply that are detected in a case where the second pole of the direct current power supply and the first terminal of the load are in the on state by the bypass circuit.

[0021] According to the power supply control method of the tenth aspect, by consuming a part of power supplied from an external charger by a bypass circuit, it is possible to perform operation diagnosis of a first switching section that is a cut-off relay even in a state in which the external charger is connected.

[0022] Effects of Invention

[0023] According to the power supply control device, the power supply control method, and the non-transitory computer-readable recording medium storing a power supply control program of the present disclosure, it is possible to perform operation diagnosis of a cut-off relay even in a state in which an external charger is connected. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 A block diagram showing one example of a power supply control device according to the present embodiment.

[0025] Figure 2 A block diagram showing one example of a hardware structure of a controller according to the present embodiment.

[0026] Figure 3 A flowchart showing one example of a process of the controller of the power supply control device according to the present embodiment.

[0027] Figure 4A diagram for illustrating a case where the cut-off relay becomes an open state and voltage drop occurs through the dark current generation circuit.

[0028] Figure 5 A diagram for illustrating one example of current in a case where the bypass circuit is set to an on state.

[0029] Figure 6 A diagram for illustrating one example of current in a case where the voltage drops to a predetermined threshold voltage or more in a state where the bypass circuit is set to an on state.

[0030] Figure 7 A diagram for illustrating one example of current in a case where the voltage drops to less than a predetermined threshold voltage in a state where the bypass circuit is set to an on state.

[0031] Figure 8 A diagram for illustrating one example of a judgment condition of the cut-off relay in the power supply control device according to the present embodiment. DETAILED DESCRIPTION

[0032] Hereinafter, the power supply control device 100 according to the present embodiment will be described using Figure 1 Figure 1 The power supply control device 100 illustrated in FIG. 1 is mounted on a vehicle 200, and has a function of diagnosing an operating state of a cut-off relay 32 connected to a power supply 30 that is a direct current power supply capable of charging and discharging. The power of the power supply 30 is supplied as current 210 to a load 20 in the vehicle 200, but in a case where an abnormal current or the like occurs, the contact of the cut-off relay 32 becomes an open state in order to perform circuit protection, thereby cutting off the power supply from the power supply 30 to the load 20.

[0033] The power supply 30 is a secondary battery or the like capable of charging and discharging, and is a lead storage battery, a nickel-hydrogen battery, a nickel-cadmium battery, a lithium battery, or the like as one example.

[0034] As Figure 1 ​As shown, the cut-off relay 32 is provided with a coil 32CA and a coil 32CB. The coil 32CA is excited by making the switch 32SA ON, and the coil 32CB is excited by making the switch 32SB ON. For example, when the switch 32SA is ON and the switch 32SB is OFF, the cut-off relay 32 becomes an open state. Further, when the switch 32SA is OFF and the switch 32SB is ON, the cut-off relay 32 becomes a closed state. The current involved in the power supply 30 is detected by the current sensor 40. The current sensor 40 is constituted by a shunt resistor 40R and a current measuring circuit 40C, and the current measuring circuit 40C calculates the current value involved in the power supply 30 based on the potential difference across the shunt resistor 40R, and outputs the calculated current value 400 to the control section 14 described later.

[0035] The power supply control device 100 includes, in addition to the current sensor 40, a dark current generating circuit 34 which makes the current of the power supply 30 flow to the load 20 or the like when the cut-off relay 32 is in the open state, a monitoring circuit 36 which monitors the energization state of the dark current generating circuit 34, and a bypass circuit 38 which becomes ON when the external charger 22 is connected to the circuit of the vehicle 200 and the current 220 flows from the external charger 22 to the circuit of the vehicle 200, to cope with the influence of the current 220 at the time of diagnosis of the state of the cut-off relay 32.

[0036] The dark current generating circuit 34 and the cut-off relay 32 are provided in parallel. The dark current generating circuit 34 includes an IPD (Intelligent Power Device) 34I which is a semiconductor switch with a protection circuit built in, with a first terminal connected to the anode of the power supply 30 and the first terminal of the cut-off relay 32, and a second terminal connected to the drain of a switching element 34F such as a field effect transistor, and the switching element 34F with the drain connected to the second terminal of the IPD 34I and the source connected to the second terminal of the cut-off relay 32 and the first terminal of the load 20.

[0037] The IPD 34I becomes ON by being applied with a control signal 340A, and in the event of an abnormal current or the like due to a short circuit or the like of the circuit, the IPD 34I absorbs the load caused by the abnormal current or the like by the protection circuit built in, and outputs a signal 340B indicating that an abnormality has occurred to the control section 14.

[0038] The switching element 34F is turned on by the control signal 340C applied to the gate. The switching element 34F is used as a variable resistor by a linear region in which the conductivity varies according to the voltage value of the control signal 340C applied to the gate, thereby functioning as a variable resistor.

[0039] The IPD 34I is a switch that is turned on to supply a dark current to the circuit of the vehicle 200 in a state where the ignition switch or the power switch of the vehicle 200 or the like is turned off, and the switching element 34F functions as a resistor to lower the voltage of the power supply 30 to become the dark current.

[0040] The monitoring circuit 36 includes a resistor 36R having a first end connected to the second end of the IPD 34I, a switch 36S having a first end connected to a second end of the resistor 36R and a second end connected to the source of the switching element 34F, the second end of the cut-off relay 32, and a first end of the load 20, and an amplifier 36A that amplifies the potential difference between both ends of the resistor 36R.

[0041] The monitoring circuit 36 generates a potential difference between both ends of the resistor 36R by turning on the switch 36S. The generated potential difference is amplified by the amplifier 36A and output as a voltage value 360 to the control section 14.

[0042] The bypass circuit 38 is provided in parallel with the power supply 30 and the cut-off relay 32. Further, the bypass circuit 38 has the switch 38SA, the resistor 38RA, the resistor 38RB, and the switch 38SB connected in series, and a first end of the switch 38SB is connected to the negative electrode of the power supply 30 and first ends of the switches 38SA are connected to the second end of the switch 36S, the source of the switching element 34F, and the second end of the cut-off relay 32, respectively. The control section 14 turns on the switches 38SA and 38SB of the bypass circuit 38 to dissipate the remaining power using the resistors 38RA and 38RB to suppress the influence of the current 220 in a case where it is determined that the external charger 22 has been connected to the circuit of the vehicle 200.

[0043] The current measurement circuit 40C, the dark current generation circuit 34, the monitoring circuit 36, and the bypass circuit 38 described above constitute the power supply monitoring unit 12. Further, the power supply unit 10 is constituted by the power supply 30 and the power supply monitoring unit 12.

[0044] Figure 2A block diagram showing one example of the hardware structure of the control section 14 according to the present embodiment. The control section 14 is a computer that includes a CPU (Central Processing Unit) 42 as one example of a hardware processor, a ROM (Read Only Memory) 44, a RAM (Random Access Memory) 46, and an input / output port 48.

[0045] In the control section 14, the CPU 42, the ROM 44, the RAM 46, and the input / output port 48 are connected to each other via various buses such as an address bus, a data bus, and a control bus. To the input / output port 48, the power supply monitoring unit 12 and a vehicle ECU (Electronic Control Unit) 50 that controls the load 20 of the vehicle 200 and the like are connected, respectively.

[0046] Further, the CPU 42 of the control section 14 has a judging function and a switch control function by a program of power supply control, the judging function being a function of judging the state of the cut-off relay 32 and the presence or absence of charging of the power supply 30 by the external charger based on the potential difference detected by the monitoring circuit 36 and the current detected by the current sensor 40, and the switch control function being a function of controlling various switches including the cut-off relay 32. By causing the CPU 42 to load the program having the respective functions and execute, the CPU 42 functions as a judging section and a switch control section.

[0047] The program can be stored in the ROM 44, the RAM 46, or the like, or can be stored in a non-transitory recording medium such as an HDD or an SSD and loaded into the CPU 42 via the RAM 46. Further, the program can be stored in an external server and loaded into the CPU 42 via a network and the RAM 46.

[0048] Figure 3 A flowchart showing one example of the processing of the control section 14 of the power supply control device 100 according to the present embodiment. Figure 3 The processing shown is started to be performed when the ignition switch or the power supply switch of the vehicle 200 becomes on.

[0049] In step 300, the current-cutting relay 32 is set to the open-circuit state. By setting the current-cutting relay 32 to the open-circuit state, IPD 34I and switching element 34F are turned on, thereby energizing the dark current generation circuit 34. If dark current is supplied to the vehicle 200 while the ignition switch or power switch is off, IPD 34I and switching element 34F will be pre-turned on.

[0050] When the current-cutting relay 32 is in the open circuit state, the dark current generation circuit 34 will behave like... Figure 4 As shown, this results in a voltage drop V. f This is because the current from power supply 30 does not flow to the circuit on the load 20 side via the open-circuit relay 32, but is instead supplied with dark current to the circuit on the load 20 side via the switching element 34F that lowers the voltage of power supply 30. Furthermore, regardless of whether the current-cutting relay 32 is in an open-circuit or closed-circuit state, the current sensor 40 detects the current I. a The test is performed. When the current-cutting relay 32 is in the closed state, the current I... a The current I will increase when the current-cutting relay 32 is in the open circuit state and when the current flows through the dark current generating circuit 34, which has a larger resistance value compared to the current-cutting relay 32. a It will decrease.

[0051] In step 302, the voltage drop V detected by the monitoring circuit 36, which is turned on by switch 36S, is... f The system determines whether the voltage exceeds a predetermined threshold voltage. The predetermined threshold voltage is calculated based on the circuit structure and further determined through experiments conducted on a real machine.

[0052] In step 302, the voltage drop V detected by the monitoring circuit 36 ​​is... f If the voltage is above the predetermined threshold voltage, in step 304, it is determined that the current-cutting relay 32 is in normal operation in the open circuit state and the process ends.

[0053] In step 302, the voltage drop V detected by the monitoring circuit 36 ​​is... f If the voltage is less than a predetermined threshold voltage, in step 306, the current I measured by the current sensor 40 is... a The determination is made based on whether the current exceeds a predetermined threshold. The predetermined threshold current is calculated based on the circuit structure and further determined through experiments conducted on a real machine.

[0054] The current I measured by the current sensor 40 in step 306 aFor the case where the current I measured by the current sensor 40 is equal to or greater than the predetermined threshold current, in step 308, it is determined that the cut-off relay 32 is in an abnormal state in which it is stuck in the closed state, and the process is ended.

[0055] In step 306, the current I measured by the current sensor 40 is compared with the predetermined threshold current. a For the case where the current I measured by the current sensor 40 is less than the predetermined threshold current, since there is a possibility that the power supply 30 is being charged by the external charger 22, in step 310, the switches 38SA, 38SB are each set to ON, so that the bypass circuit 38 is brought to the conductive state. When the bypass circuit 38 is brought to the conductive state in a state in which the external charger 22 that supplies electric power is connected to the circuit of the vehicle 200, a current 250 as shown in FIG. 8 flows in the circuit of the vehicle 200. Figure 5

[0056] In step 312, the current I measured by the current sensor 40 is compared with the predetermined threshold current. a For the case where the current I measured by the current sensor 40 is equal to or greater than the predetermined threshold current, in step 314, it is determined that the external charger 22 is being connected. Then, in step 316, the state determination of the cut-off relay 32 is suspended, and the process is ended.

[0057] In step 312, the current I measured by the current sensor 40 is compared with the predetermined threshold current. a For the case where the current I measured by the current sensor 40 is equal to or greater than the predetermined threshold current, in step 314, it is determined that the external charger 22 is being connected. Then, in step 316, the state determination of the cut-off relay 32 is suspended, and the process is ended.

[0058] In step 318, the voltage drop V detected by the monitoring circuit 36 is compared with the predetermined threshold voltage. f When electric power is supplied from the external charger 22 to the circuit including the power supply 30, the voltage of the terminal on the load 20 side of the switching element 34F that constitutes the dark current generation circuit 34 rises, so that the potential difference across the switching element 34F decreases, so that the voltage drop V is suppressed. However, by causing the electric power supplied from the external charger 22 to flow in the bypass circuit 38, it is possible to dissipate a portion of the electric power using the resistors 38RA, 38RB that constitute the bypass circuit 38. As a result, it is possible to suppress the rise in the voltage of the terminal on the load 20 side of the switching element 34F that constitutes the dark current generation circuit 34. f

[0059] In step 318, the voltage drop V detected by the monitoring circuit 36 is compared with the predetermined threshold voltage. f For the case where the voltage drop V detected by the monitoring circuit 36 is equal to or greater than the predetermined threshold voltage, in step 320, it is determined that the cut-off relay 32 is in the normal open state, and the process is ended. For the case where the voltage drop V detected by the monitoring circuit 36 is less than the predetermined threshold voltage, in step 322, it is determined that the cut-off relay 32 is in the abnormal state in which it is stuck in the closed state, and the process is ended. f For the case where the voltage drop V detected by the monitoring circuit 36 is equal to or greater than the predetermined threshold voltage, a current 250 as shown in FIG. 8 flows in the circuit of the power supply control device 100. Figure 6 ​​The current 260 shown.

[0060] In a case where the voltage drop V f detected by the monitoring circuit 36 is less than a predetermined threshold voltage, it is determined in step 322 that the cut-off relay 32 is in an abnormal state in which it is stuck in the closed state, and the process ends. In a case where the voltage drop V f detected by the monitoring circuit 36 is less than a predetermined threshold voltage, the current I Figure 7 flowing in the circuit of the power supply control device 100 is shown as 270, so that the voltage of the terminal on the load 20 side of the switching element 34F constituting the dark current generation circuit 34 is easily raised.

[0061] Figure 8 This is a diagram for illustrating one example of a determination condition of the cut-off relay 32 in the power supply control device 100 according to the present embodiment. The determination condition is the magnitude of the voltage drop V f , the magnitude of the current I a , the on / off of the bypass circuit 38, and the presence / absence of the external charger 22.

[0062] In a case where the voltage drop V f is equal to or greater than a predetermined threshold voltage, and the bypass circuit 38 is off, it is determined that the cut-off relay 32 is normal in the open state regardless of the presence / absence of the external charger 22.

[0063] In a case where the voltage drop V f is less than a predetermined threshold voltage, the magnitude of the current I a is equal to or greater than a predetermined threshold current, and the bypass circuit 38 is off, it is determined that the cut-off relay 32 is stuck in the closed state and is abnormal.

[0064] Regardless of the value of the voltage drop V f , in a case where the magnitude of the current I a is equal to or greater than a predetermined threshold current, the bypass circuit 38 is on, and the external charger 22 is present, it is determined that the external charger 22 is connected, but since it is difficult to accurately determine the state of the cut-off relay 32 in this case, the determination of the state of the cut-off relay 32 is suspended.

[0065] In a case where the voltage drop V f is equal to or greater than a predetermined threshold voltage, the magnitude of the current I a is less than a predetermined threshold current, and the bypass circuit 38 is on, it is determined that the cut-off relay 32 is normal in the open state.

[0066] In a case where the voltage drop V f is less than a predetermined threshold voltage, the magnitude of the current Ia If the size of the voltage drop V

[0067] As explained above, in the present embodiment, in a case where the voltage drop V f generated by the dark current generation circuit 34 can be suppressed using the power supplied from the external charger 22 to charge the power supply 30, a part of the power supplied from the external charger 22 is consumed by the bypass circuit 38 provided with the resistors 38RA, 38RB. Due to the consumption of the power, the voltage drop V f generated by the dark current generation circuit 34 is surfaceized, so that it is possible to determine a case where the cut-off relay 32 is in the open circuit state.

[0068] Further, in a state where a part of the power supplied from the external charger 22 is consumed by the bypass circuit 38, not only the state of the cut-off relay 32 is determined based on the detected voltage drop V f and the current I a , but also it is possible to determine whether the charging of the power supply 30 by the external charger 22 is being performed.

[0069] Although in the present embodiment the cut-off relay 32 and the dark current generation circuit 34 and the like are connected to the positive electrode of the power supply 30, it is not limited thereto. It is also possible to reverse the state described in JP 2007- 271 1 1 A and the like, so that the cut-off relay 32 and the dark current generation circuit 34 and the like are connected to the negative electrode of the power supply 30. In a case where the polarity of the power supply 30 is reversed, the polarity of the external charger 22, the load 20, the switching element 34F and the like is also reversed as needed from the state shown in JP 2007- 271 1 1 A and the like. Figure 1 Figure 1

[0070] respectively, the "direct current power supply" corresponds to the "power supply 30", the "first switching section" corresponds to the "cut-off relay 32", the "voltage detection section" corresponds to the "monitoring circuit 36", the "current detection section" corresponds to the "current sensor 40", the "second switching section" corresponds to the "switches 38SA, 38SB", and the "resistor section" corresponds to the "resistors 38RA, 38RB".

[0071] ​​In addition, the processing performed by the CPU 42 in the software (program) in each of the above-described embodiments can also be performed by various processors other than the CPU. As the processor in this case, a PLD (Programmable Logic Device) such as an FPGA (Field-Programmable Gate Array) in which the circuit structure can be changed after manufacture, an ASIC (Application Specific Integrated Circuit) in which a circuit structure designed specifically for performing a certain processing is provided, and the like can be exemplified. Furthermore, the processing can be performed by one of these various processors, or by a combination of two or more processors of the same kind or different kinds (for example, a plurality of FPGAs, a combination of a CPU and an FPGA, and the like). Furthermore, more specifically, the hardware structure of these various processors is a circuit in which circuit elements such as semiconductor elements are combined.

Claims

1. A power control device, comprising: A current-cutting relay connects or disconnects the first terminal of the load from the first terminal of the DC power supply. A dark current generating circuit generates dark current by causing the voltage of the DC power supply to drop when the first terminal is connected to the first pole of the DC power supply and the second terminal is connected to the first terminal of the load in a manner that is in parallel with the current-cutting relay. A bypass circuit that, when the DC power supply is being charged by an external charger, depletes a portion of the power supplied from the external charger by connecting the second terminal of the DC power supply to the first terminal of the load.

2. The power control device as described in claim 1, in, include: Memory; The processor, which is connected to the memory, The processor is configured such that, The potential difference between the second terminal and the first terminal of the dark current generation circuit is detected. The current between the second terminal of the load and the second terminal of the DC power supply is detected. The current-cutting relay is controlled to turn on or off, and its state is determined based on the detected potential difference and current.

3. The power control device as described in claim 2, wherein, The processor is configured such that, If the detected potential difference is above a predetermined threshold voltage, the current-cutting relay is determined to be in an open-circuit state.

4. The power control device as described in claim 2, wherein, The processor is configured such that, If the detected potential difference is less than a predetermined threshold voltage and the detected current is above a predetermined threshold current, it is determined that the current-cutting relay is stuck in the closed-circuit state.

5. The power control device as described in claim 2, wherein, The bypass circuit includes a switch and a resistor. The switch connects or disconnects the first terminal of the load from the second terminal of the DC power supply, and the resistor depletes a portion of the power supplied. The processor is configured such that, If the detected potential difference is less than a predetermined threshold voltage and the detected current is less than a predetermined threshold current, the second terminal of the DC power supply is connected to the first terminal of the load by setting the switch to on.

6. The power control device as described in claim 5, wherein, The processor is configured such that, If the current detected when the bypass circuit conducts between the second terminal of the DC power supply and the first terminal of the load is above a predetermined threshold current, it is determined that the charging of the DC power supply by the external charger is in progress.

7. The power control device as described in claim 5, wherein, The processor is configured such that, If the current detected when the bypass circuit conducts between the second terminal of the DC power supply and the first terminal of the load is less than a predetermined threshold current and the detected potential difference is greater than a predetermined threshold voltage, it is determined that the current-cutting relay is in an open circuit state.

8. The power control device as described in claim 5, wherein, The processor is configured such that, If the current detected is less than a predetermined threshold current and the potential difference detected is less than a predetermined threshold voltage when the bypass circuit conducts between the second terminal of the DC power supply and the first terminal of the load, it is determined that the current-cutting relay is stuck in the closed-circuit state.

9. The power control device according to any one of claims 1 to 8, wherein, The current-cutting relay is mounted on the vehicle.

10. A power supply control method, wherein, The processor performs the following processing: The potential difference between the second terminal and the first terminal of the dark current generation circuit is detected. The dark current generation circuit is configured such that its first terminal is connected to the first terminal of the DC power supply and its second terminal is connected to the first terminal of the load, in a state where the first terminal of the DC power supply is connected in parallel with a current-cutting relay that controls the conduction or cutoff between the first terminal of the load and the first terminal of the DC power supply. This causes a drop in the voltage of the DC power supply, thereby generating a dark current. The current between the second terminal of the load and the second terminal of the DC power supply is detected. The state of the current-cutting relay is determined based on the potential difference and the current. When the potential difference is less than a predetermined threshold voltage and the current is less than a predetermined threshold current, the bypass circuit is turned on. In this state, the bypass circuit depletes a portion of the power supplied from the external charger while the second terminal of the DC power supply is connected to the first terminal of the load. The state of the current-cutting relay and the presence or absence of charging of the DC power supply by the external charger are determined based on the potential difference between the second and first terminals of the dark current generation circuit and the current between the second terminal of the load and the second terminal of the DC power supply, which are detected when the second terminal of the DC power supply and the first terminal of the load are in a conducting state through the bypass circuit.

11. The power control method as described in claim 10, wherein, If the detected potential difference is above a predetermined threshold voltage, the current-cutting relay is determined to be in an open-circuit state.

12. The power control method as described in claim 10, wherein, If the detected potential difference is less than a predetermined threshold voltage and the detected current is above a predetermined threshold current, it is determined that the current-cutting relay is stuck in the closed-circuit state.

13. A non-transitory computer-readable recording medium containing a program, wherein, The program is used to cause the computer to perform the following processes: The state of the current-cutting relay is determined based on the potential difference between the second and first terminals of the dark current generation circuit and the current between the second terminal of the load and the second terminal of the DC power supply. Specifically, the dark current generation circuit is configured to operate in parallel with the current-cutting relay, which controls the connection or disconnection between the first terminal of the load and the first terminal of the DC power supply. In this configuration, the first terminal of the dark current generation circuit is connected to the first terminal of the DC power supply, and the second terminal is connected to the first terminal of the load. This causes a drop in the voltage of the DC power supply, thereby generating a dark current. When the potential difference is less than a predetermined threshold voltage and the current is less than a predetermined threshold current, the bypass circuit is controlled to be in a conducting state, wherein the bypass circuit depletes a portion of the power supplied from the external charger while the second terminal of the DC power supply is connected to the first terminal of the load. The state of the current-cutting relay and the presence or absence of charging of the DC power supply by the external charger are determined based on the potential difference between the second and first terminals of the dark current generation circuit and the current between the second terminal of the load and the second terminal of the DC power supply, which are detected when the second terminal of the DC power supply and the first terminal of the load are in a conducting state through the bypass circuit.

14. The non-transitory computer-readable recording medium of claim 13, wherein, The process includes: If the detected potential difference is above a predetermined threshold voltage, the current-cutting relay is determined to be in an open-circuit state.

15. The non-transitory computer-readable recording medium of claim 13, wherein, The process includes: If the detected potential difference is less than a predetermined threshold voltage and the detected current is above a predetermined threshold current, it is determined that the current-cutting relay is stuck in the closed-circuit state.

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