Power supply control device and power supply control program

Abstract

To provide a power supply control device capable of reducing the number of sensors required for identifying a location where a power supply failure occurs, and a power supply control program.SOLUTION: A power supply control device comprises: a common power feed line connecting a first power feed line connected to a first power source, a second power feed line connected to a second power source and a load power feed line connected to a load; a switch connecting the first power feed line with the common power feed line, a switch connecting the second power feed line with the common power feed line, a switch connecting the load power feed line with the common power feed line; a sensor provided in the common power feed line and detecting a power feed state; and a controller by which, when a power supply failure is detected based on output of the sensor, the switches are turned off in accordance with priorities which are set to the first power feed line, the second power feed line and the load power feed line, and a location where the power supply failure occurs is identified based on the output of the sensor.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The disclosed embodiments relate to a power supply control device and a power supply control program. [Background technology]

[0002] A redundant power supply device is known in which each load is connected in parallel to a power supply line via a load switch, a first power supply is connected to the power supply line via a first power supply switch, and a second power supply is connected to the power supply line via a second power supply switch (see, for example, Patent Document 1).

[0003] The device described in Patent Document 1 locates the location of a power supply failure, such as a ground fault, based on the outputs of a sensor provided between each load and each load switch, a sensor provided between the power supply line and the first power supply, and a sensor provided between the power supply line and the second power supply.

[0004] The device described in Patent Document 1 then turns off the switch corresponding to the identified location where the power failure has occurred, thereby isolating the location where the power failure has occurred from the power supply circuit. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2023-42332 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the device described in Patent Document 1 requires many sensors to identify the location where the power failure has occurred.

[0007] One aspect of the embodiment has been made in consideration of the above, and aims to provide a power supply control device and a power supply control program that can reduce the number of sensors required to identify the location of a power failure. [Means for solving the problem]

[0008] A power supply control device according to an embodiment includes a common power supply line. The common power supply line connects a first power supply line connected to a first power source, a second power supply line connected to a second power source, and a load power supply line connected to a load. The power supply control device includes a switch that connects the first power supply line and the common power supply line. The power supply control device includes a switch that connects the second power supply line and the common power supply line. The power supply control device includes a switch that connects the load power supply line and the common power supply line. The power supply control device includes a sensor. The sensor is provided on the common power supply line and detects a power supply state. The power supply control device includes a controller. The controller detects a power supply failure based on an output of the sensor. When the controller detects a power supply failure, the controller turns off the switch according to a priority order set for the first power supply line, the second power supply line, and the load power supply line, and identifies the location of the power supply failure based on the output of the sensor. Effect of the Invention

[0009] A power supply control device and a power supply control program according to one aspect of an embodiment can identify the location of a power failure using a sensor installed on a common power supply line, thereby achieving the effect of reducing the number of sensors required to identify the location of a power failure. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is an explanatory diagram illustrating an example of the configuration of a power supply control device according to the first embodiment. [Figure 2A] FIG. 2A is a flowchart showing an example of processing executed by the controller according to the first embodiment. [Figure 2B] FIG. 2B is a flowchart showing an example of processing executed by the controller according to the first embodiment. [Figure 3A]FIG. 3A is a flowchart showing an example of processing executed by the controller according to the first embodiment. [Figure 3B] FIG. 3B is a flowchart showing an example of processing executed by the controller according to the first embodiment. [Figure 4] FIG. 4 is a flowchart showing an example of processing executed by the controller according to the first embodiment. [Diagram 5] FIG. 5 is an explanatory diagram illustrating an example of the configuration of a power supply control device according to the second embodiment. [Figure 6A] FIG. 6A is a flowchart showing an example of processing executed by a controller according to the second embodiment. [Figure 6B] FIG. 6B is a flowchart showing an example of processing executed by the controller according to the second embodiment. [Figure 6C] FIG. 6C is a flowchart showing an example of processing executed by the controller according to the second embodiment. [Figure 7] FIG. 7 is a flowchart illustrating an example of processing executed by a controller according to the second embodiment. [Figure 8] FIG. 8 is a flowchart showing an example of processing executed by the controller according to the second embodiment. [Figure 9] FIG. 9 is a flowchart showing an example of processing executed by a controller according to the third embodiment. [Figure 10] FIG. 10 is a flowchart showing an example of processing executed by a controller according to the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of a power supply control device and a power supply control program will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiment described below. The power supply control device according to the embodiment is a device that controls the supply of power to an electronic device (hereinafter referred to as a "load") mounted on a vehicle.

[0012] [1. First embodiment] [1-1. Configuration example of power supply control device according to the first embodiment] Fig. 1 is an explanatory diagram showing an example of the configuration of a power supply control device 1 according to a first embodiment. As shown in Fig. 1, the power supply control device 1 is connected to a first power supply 10, a second power supply 20, a first load 41, a second load 42, a third load 43, and a fourth load 44. Here, a case where four loads are connected to the power supply control device 1 will be described, but the number of loads connected to the power supply control device 1 is not limited to four as long as it is two or more.

[0013] The first power source 10 is, for example, a lead battery mounted on a vehicle. The first power source 10 may be a secondary battery other than a lead battery. The second power source 20 is a backup power source that supplies power in place of the first power source 10 when the first power source 10 is no longer able to supply power. The second power source 20 is, for example, a lithium ion battery. The second power source 20 may be a secondary battery other than a lithium ion battery. In this embodiment, the output voltage of the second power source 20 is described as being lower than the output voltage of the first power source 10.

[0014] The first to fourth loads 41 to 44 include various electronic devices mounted on a vehicle, such as an engine control device, a steering control device, a brake control device, an audio device, a video display device, and various sensors.

[0015] The first power source 10 is electrically connected to the power supply control device 1 via a first power supply line L1. The second power source 20 is electrically connected to the power supply control device 1 via a second power supply line L2. The first to fourth loads 41 to 44 are electrically connected to the power supply control device 1 via a load power supply line L3.

[0016] The power supply control device 1 is a device that outputs and supplies power input from the first power supply 10 or the second power supply 20 to the first to fourth loads 41 to 44. The power supply control device 1 includes a common power supply line L4, first to sixth switches 11 to 16, a sensor 5, and a controller 3. The common power supply line L4 is a power supply line that electrically connects the first power supply line L1, the second power supply line L2, and the load power supply line L3.

[0017] The first switch 11 is a switch that connects the first power feed line L1 and the common power feed line L4. When the first switch 11 is turned on, the first power feed line L1 and the common power feed line L4 are electrically connected. When the first switch 11 is turned off, the first switch 11 cuts off the electrical connection between the first power feed line L1 and the common power feed line L4.

[0018] The second switch 12 is a switch that connects the second power feed line L2 and the common power feed line L4. When the second switch 12 is turned on, the second power feed line L2 and the common power feed line L4 are electrically connected. When the second switch 12 is turned off, the second switch 12 cuts off the electrical connection between the second power feed line L2 and the common power feed line L4.

[0019] The third to sixth switches 13 to 16 are switches that connect the load power supply line L3 and the common power supply line L4. Specifically, the third switch 13, when turned on, electrically connects the common power supply line L4 and the first load 41. Moreover, the third switch 13, when turned off, cuts off the electrical connection between the common power supply line L4 and the first load 41.

[0020] The fourth switch 14, when turned on, electrically connects the common power supply line L4 and the second load 42. In addition, the fourth switch 14, when turned off, electrically disconnects the common power supply line L4 and the second load 42.

[0021] The fifth switch 15, when turned on, electrically connects the common power supply line L4 and the third load 43. In addition, the fifth switch 15, when turned off, electrically disconnects the common power supply line L4 and the third load 43.

[0022] The sixth switch 16, when turned on, electrically connects the common power supply line L4 and the fourth load 44. In addition, the sixth switch 16, when turned off, electrically disconnects the common power supply line L4 and the fourth load 44.

[0023] The sensor 5 is provided on the common power supply line L4 and detects the power supply state. Here, the sensor 5 is a voltage sensor that detects the voltage of the common power supply line L4. The sensor 5 outputs the voltage detection result to the controller 3. The sensor 5 may be a current detection sensor that detects the current of the common power supply line L4. In this case, the sensor 5 outputs the current detection result to the controller 3.

[0024] The controller 3 includes a microcomputer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), etc., and various circuits. The controller 3 performs on / off control of the first to sixth switches 13-16 by the CPU executing a power control program stored in the ROM using the RAM as a working area.

[0025] The power supply control program may be stored in a storage device via an external communication line, etc. Also, the controller 3 may be partially or entirely configured with hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

[0026] [1-2. Operation of the power supply control device according to the first embodiment] Next, a description will be given of the operation of the power supply control device 1. In the following description, an area including the first power supply 10 and the first power supply line L1 is referred to as a first area A1, an area including the second power supply 20 and the second power supply line L2 is referred to as a second area A2, and an area including the first to fourth loads 41 to 44 and the load power supply line L3 is referred to as a third area A3.

[0027] In normal operation when no power failure occurs in the first to third areas A1, A2, A3, the power supply control device 1 supplies power input from the first power supply 10 to the first to fourth loads 41 to 44. Specifically, the controller 3 turns on the first to sixth switches 11 to 16 in normal operation.

[0028] At this time, since the output voltage of the first power source 10 is higher than the output voltage of the second power source, power is supplied from the first power source 10 to the first to fourth loads 41 to 44, but power is not supplied from the second power source 20 to the first to fourth loads 41 to 44.

[0029] Specifically, the power output from the first power supply 10 is supplied to the first to fourth loads 41 to 44 via the first switch 11, the common power supply line L4, the third to sixth switches 13 to 16, and the load power supply line L3.

[0030] Furthermore, when a power supply failure such as a ground fault occurs in the first area A1, the power supply control device 1 supplies power to the first to fourth loads 41 to 44 from the second power supply 20 since the first power supply 10 is no longer able to supply power.

[0031] In this case, the controller 3 turns off the first switch 11 from a state in which the first to sixth switches 11 to 16 are on. As a result, the power output from the second power supply 20 is supplied to the first to fourth loads 41 to 44 via the second switch 12, the common power supply line L4, the third to sixth switches 13 to 16, and the load power supply line L3.

[0032] Furthermore, when a power failure such as a ground fault occurs in the second area A2, the power supply control device 1 continues power supply from the first power supply 10 to the first to fourth loads 41 to 44 while suppressing discharge from the first power supply 10 to the second power supply 20.

[0033] In this case, the controller 3 turns off the second switch 12 from a state in which the first to sixth switches 11 to 16 are turned on. As a result, the power output from the first power supply 10 is not discharged to the second power supply 20, but is continuously supplied to the first to fourth loads 41 to 44 via the first switch 11, the common power supply line L4, the third to sixth switches 13 to 16, and the load power supply line L3.

[0034] In addition, if a power failure such as a ground fault occurs in the third area A3, the power supply control device 1 disconnects the part of the load power supply line L3 where the power failure occurred from the common power supply line L4, and continues power supply through the load power supply line L3 where no power failure has occurred.

[0035] For example, when a ground fault occurs in the load power supply line L3 connecting the first load 41 and the common power supply line L4, the controller 3 turns off the third switch 13 from a state in which the first to sixth switches 11 to 16 are turned on. This enables the controller 3 to disconnect the portion where the ground fault occurs from the common power supply line L4.

[0036] As a result, the power output from the first power supply 10 is continuously supplied to the second to fourth loads 42 to 44 via the first switch 11, the common power supply line L4, the fourth to sixth switches 14 to 16, and the load power supply line L3.

[0037] Here, in order to perform appropriate power supply control when a power failure occurs, the controller 3 needs to accurately identify where in the first to third areas A1, A2, A3 the power failure has occurred.

[0038] At this time, if sensors 5 are provided, for example, between the first power source 10 and the first switch 11, between the second power source 20 and the second switch 12, and between the third to sixth switches 13 to 16 and the first to fourth loads 41 to 44, the controller 3 can easily identify the location where the power failure has occurred.

[0039] Specifically, if a sensor provided between the first power source 10 and the first switch 11 quickly detects a voltage equal to or lower than the ground fault threshold, the controller 3 can identify the location of the power failure as the first area A1. Also, if a sensor provided between the second power source 20 and the second switch 12 quickly detects a voltage equal to or lower than the ground fault threshold, the controller 3 can identify the location of the power failure as the second area A2.

[0040] Furthermore, if any of the sensors 5 provided between the third to sixth switches 13-16 and the first to fourth loads 41-44 detects a voltage equal to or lower than the ground fault threshold value early, the controller 3 can identify the power supply line on which the sensor is provided as the location of the power supply failure. However, in such a configuration, many sensors are required to identify the location of the power supply failure.

[0041] Therefore, the power supply control device 1 according to the embodiment includes one sensor 5 provided on the common power supply line L4. The controller 3 controls the first to sixth switches 11 to 16 based on the power supply state of the common power supply line L4 detected by the one sensor 5, thereby identifying the exact location where the power failure has occurred.

[0042] First, the controller 3 detects the occurrence of a power supply failure based on the output of the sensor 5. Specifically, if the voltage of the common power supply line L4 detected by the sensor 5 is equal to or lower than a ground fault threshold, the controller 3 determines that a ground fault has occurred somewhere.

[0043] Thereafter, the controller 3 turns off the switches according to the priorities set for the first power feed line L1, the second power feed line L2, and the load power feed line L3. In other words, the controller 3 turns off the switches belonging to the areas according to the priorities set for the first area A1 to which the first power feed line L1 belongs, the second area A2 to which the second power feed line L2 belongs, and the third area A3 to which the load power feed line L3 belongs. For example, when the priority of the first power feed line L1 (or the first area A1) is the first, the priority of the load power feed line L3 (or the third area A3) is the second, and the priority of the second power feed line L2 (or the second area A2) is the third, the controller 3 turns off the first switch 11 of the first power feed line L1 first from the state in which the first to sixth switches 11 to 16 are on.

[0044] As a result, if the voltage detected by the sensor 5 returns to a level exceeding the ground fault threshold, the controller 3 can identify the location of the ground fault as the first area A1. If the voltage detected by the sensor 5 does not return to a level exceeding the ground fault threshold, the controller 3 can determine that the location of the ground fault is not the first area A1, that is, that the location of the ground fault is the second area A2 or the third area A3.

[0045] In this case, the controller 3 turns off the first switch 11, keeps the second switch 12 on, and turns off all of the third to sixth switches 13-16 connected to the load power supply line L3, which has the second priority.

[0046] As a result, if the voltage detected by the sensor 5 does not return to normal until it exceeds the ground fault threshold, in other words, if the power failure is continuously detected, the controller 3 can identify the location where the ground fault has occurred as the second area A2.

[0047] If all of the third to sixth switches 13 to 16 are turned off, the power supply to the first to fourth loads 41 to 44 will be cut off, causing problems with running. However, since each load has a capacitance component such as a capacitor for smoothing the power supply, even if all of the third to sixth switches 13 to 16 are turned off, the load can still operate until the voltage stored in the capacitance component drops to a voltage at which the load stops operating. Therefore, it is desirable to set the period during which all of the third to sixth switches 13 to 16 are turned off within the time it takes for the voltage stored in the capacitance component to reach a voltage at which the load stops operating.

[0048] Furthermore, if the voltage detected by the sensor 5 returns to exceed the ground fault threshold when all of the third to sixth switches 13-16 are turned off, that is, if a power failure is no longer detected, the controller 3 can identify the location where the ground fault has occurred as the third area A3. In this case, the controller 3 turns on the third to sixth switches 13-16 one by one in sequence, and turns off the remaining switches among the third to sixth switches 13-16.

[0049] In this case, when one of the third to sixth switches 13-16 is turned on and the remaining switches are turned off, if the voltage detected by the sensor 5 becomes equal to or lower than the ground fault threshold value, the load power supply line L3 connected to that switch can be identified as the location where the ground fault has occurred.

[0050] For example, the controller 3 turns on the third switch 13 among the third to sixth switches 13 to 16, turns off the fourth to sixth switches 14 to 16, and if the voltage detected by the sensor 5 becomes equal to or lower than the ground fault threshold, the load power supply line L3 connecting the third switch 13 and the first load 41 can be identified as the ground fault location. Note that, here too, it is desirable that the period during which one switch is turned on and the remaining switches are turned off is within the time it takes for the voltage stored in the capacitive component of the load connected to the line where the switch is turned off to reach the voltage at which the load stops operating.

[0051] The priorities set for the first power supply line L1 (or the first area A1), the second power supply line L2 (or the second area A2), and the load power supply line L3 (or the third area A3) are set in advance as a table in the controller 3. The controller 3 reads the priority of each power supply line (or area) from the table and turns off the switch according to the priority. This priority is set, for example, in descending order of the power supply line that has statistically experienced the greatest number of power failures in the power supply control device 1 in the past. This enables the controller 3 to identify the location of the power supply failure at an early stage.

[0052] [1-3. Processing Executed by the Controller According to the First Embodiment] Next, a description will be given of the processing executed by the controller 3 according to the first embodiment. Figures 2A to 4 are flowcharts showing an example of the processing executed by the controller 3 according to the first embodiment.

[0053] When the vehicle is started, the controller 3 executes the process shown in Fig. 2A and Fig. 2B. Specifically, as shown in Fig. 2A, when the vehicle is started, the controller 3 reads out from a table stored in the memory the priority order of the power supply lines that identifies the location of a power failure when a power failure occurs (step S100). Next, the controller 3 first turns on the first to sixth switches 11 to 16 (step S101). As a result, power is supplied from the first power source 10 and the second power source 20 to the first to fourth loads 41 to 44. In reality, since the voltage of the first power source 10 is higher than the voltage of the second power source 20, power is supplied from the first power source 10 to the first to fourth loads 41 to 44.

[0054] Next, the controller 3 determines whether or not the voltage of the common power supply line L4 detected by the sensor 5 has dropped to a ground fault threshold value or lower (hereinafter, referred to as "voltage drop") (step S102). When the controller 3 determines that the voltage of the common power supply line L4 has not dropped (step S102, No), the controller 3 shifts the process to step S101.

[0055] Furthermore, when the controller 3 determines that the voltage of the common power supply line L4 has dropped (step S102, Yes), it turns off the switch connected to the power supply line with the first priority (hereinafter, sometimes referred to as the first priority), that is, the switch belonging to the first priority area (step S103). This separates the first priority area from the power supply circuit.

[0056] For example, if the first power supply line L1 (first area A1) has the highest priority, the first switch 11 is turned off. This causes the first area A1 to be disconnected from the power supply circuit. If the second power supply line L2 (second area A2) has the highest priority, the second switch 12 is turned off. This causes the second area A2 to be disconnected from the power supply circuit. If the load power supply line L3 (third area A3) has the highest priority, the third to sixth switches 13 to 16 are turned off. This causes the third area A3 to be disconnected from the power supply circuit.

[0057] At this time, if a ground fault occurs in the first priority area, the controller 3 will no longer detect a power failure because the voltage of the common power supply line L4 will return to normal until it exceeds the ground fault threshold (hereinafter, this will be referred to as "voltage recovery").

[0058] Specifically, when the first priority area is the first area A1 and a ground fault occurs in the first area A1, the first switch 11 in the first area A1 is turned off, and the ground fault location is separated from the common power feed line L4. On the other hand, since the second power source 20 is connected to the common power feed line L4, the voltage of the common power feed line L4 is restored until it exceeds the ground fault threshold. The same applies when the first priority area is the second area A2 or the third area A3. That is, if a ground fault occurs in the first priority area, the controller 3 separates the first priority area from the common power feed line L4, and since at least one of the first power source 10 or the second power source 20 is connected to the common power feed line L4, the voltage of the common power feed line L4 is restored, and the controller 3 no longer detects the power supply failure. Also, if a ground fault does not occur in the first priority area, the controller 3 continues to detect the power supply failure because the voltage is not restored. In this case, the ground fault area is the second priority area or the third priority area.

[0059] Therefore, after turning off the switch of the first priority area in step S103, the controller 3 determines whether the voltage has been restored (step S104). If the controller 3 determines that the voltage has been restored (step S104, Yes), the controller 3 determines that a ground fault has occurred in the first priority area (step S105).

[0060] Furthermore, if the controller 3 determines that the voltage does not recover after turning off the switch in the first priority area in step S103 (step S104, No), it turns off the switch connected to the power supply line with the second highest priority (hereinafter, sometimes referred to as the second priority), that is, the switch belonging to the second priority area (step S106). This separates the second priority area from the power supply circuit.

[0061] Next, the controller 3 turns on the switch of the first priority area (step S107). If the first priority area is the first area A1 (or the second area A2) and the second priority area is the second area A2 (or the first area A1), the switches of the first area A1 and the second area A2 are turned off in steps S103 and S106, and the power supply to the common power feed line L4 is cut off. To prevent this, the controller 3 turns on the switch of the first priority area in step S107. This allows power to be supplied to the common power feed line L4 from at least one of the first power source 10 and the second power source 20.

[0062] At this time, if a ground fault occurs in the second priority area, the controller 3 no longer detects a power failure because the voltage of the common power supply line L4 is restored until it exceeds the ground fault threshold value. On the other hand, if a ground fault does not occur in the second priority area, the controller 3 continues to detect a power failure because the voltage is not restored.

[0063] Therefore, the controller 3 turns off the switch of the second priority area in step S106, and after turning on the switch of the first priority area in step S107, determines whether the voltage has been restored (step S108). If the controller 3 determines that the voltage has been restored (step S108, Yes), it determines that a ground fault has occurred in the second priority area (step S109).

[0064] Furthermore, if the controller 3 determines that the voltage does not recover after turning off the switch of the second priority area in step S106 and turning on the switch of the first priority area in step S107 (step S108, No), it determines that a ground fault has occurred in the third priority area (step S110). As described above, when the controller 3 detects a voltage drop in step S102, it performs the processes of steps S103 to S110 and determines the area in which a ground fault has occurred.

[0065] 2B, the controller 3 determines whether the area where the ground fault has occurred is the third area A3 (step S111). If the controller 3 determines that the area where the ground fault has occurred is the third area A3 (step S111, Yes), the controller 3 sequentially turns on the third to sixth switches 13 to 16 and turns off the remaining switches among the third to sixth switches 13 to 16 to identify the location of the ground fault in the third area A3 (step S112).

[0066] Thereafter, the controller 3 turns off the switch connected to the ground-fault load that is the load of the ground-fault location among the third to sixth switches 13-16, turns on the remaining switches, turns on the first switch 11 and the second switch 12 (step S113), and ends the process. As a result, power is supplied from the first power source 10 and the second power source 20 to the loads that are not connected to the ground-fault location among the first to fourth loads 41-44.

[0067] On the other hand, when the controller 3 determines that the area where the ground fault occurred is not the third area A3 (step S111, No), it turns off the switch of the confirmed ground fault area, turns on all other switches (step S114), and ends the process. For example, when the confirmed ground fault area is the first area A1, the controller 3 turns off the first switch 11, and turns on the second switch 12 and the third to sixth switches 13 to 16. This allows power to be supplied from the second power source 20 to the first to fourth loads 41 to 44. On the other hand, when the confirmed ground fault area is the second area A2, the controller 3 turns off the second switch 12, and turns on the first switch 11 and the third to sixth switches 13 to 16. This allows power to be supplied from the first power source 10 to the first to fourth loads 41 to 44.

[0068] So far, we have described the case where the controller 3 detects the occurrence of a ground fault when the voltage of the common power supply line L4 drops. However, the controller 3 may also be configured to determine whether a drop in the voltage of the common power supply line L4 is a temporary voltage drop or a ground fault.

[0069] Next, a process executed by the controller 3 configured to determine whether a transient voltage drop or a ground fault has occurred will be described. When the vehicle is started, the controller 3 configured to determine whether a transient voltage drop or a ground fault has occurred executes the process shown in Figs. 3A, 3B, and 4.

[0070] Specifically, as shown in Fig. 3A, the controller 3 reads out from a table stored in the memory the priority order of the power supply lines that identifies the location of the failure when a power supply failure occurs (step S300). Next, when the vehicle is started, the controller 3 first turns on the first to sixth switches 11 to 16 (step S301). As a result, power is supplied from the first power source 10 and the second power source 20 to the first to fourth loads 41 to 44.

[0071] Next, the controller 3 determines whether the voltage of the common power supply line L4 has dropped to a ground fault threshold or lower (step S302). When the controller 3 determines that the voltage of the common power supply line L4 has not dropped (step S302, No), the controller 3 shifts the process to step S301.

[0072] Furthermore, when the controller 3 determines that the voltage of the common power supply line L4 has dropped (step S302, Yes), it turns off the switch connected to the power supply line with the first priority, that is, turns off the switch belonging to the first priority area (step S303). This separates the first priority area from the power supply circuit.

[0073] At this time, if a ground fault or a transient voltage drop occurs in the first priority area, the voltage of the common power supply line L4 is restored and the controller 3 no longer detects the power supply failure. On the other hand, if a ground fault does not occur in the first priority area, the voltage is not restored and the controller 3 continues to detect the power supply failure.

[0074] Therefore, after turning off the switch of the first priority area in step S303, the controller 3 judges whether the voltage has been restored (step S304). If the controller 3 judges that the voltage has been restored (step S304, Yes), it judges that the first priority area has a ground fault or a temporary voltage drop (step S305) and turns on the switch of the first priority area again after a certain time has elapsed (step S306). As a result, the first priority area is again connected to the power supply circuit. At this time, if the first priority area has a ground fault, the voltage of the common power supply line L4 remains low, but if the voltage drop is a temporary voltage drop, the voltage of the common power supply line L4 has been restored.

[0075] 3B, the controller 3 determines whether the voltage of the common power supply line L4 has dropped (step S307). If the controller 3 determines that the voltage of the common power supply line L4 has dropped (step S307, Yes), the controller 3 determines that a ground fault has occurred in the first priority area (step S308) and proceeds to step S323.

[0076] In addition, if the controller 3 determines that the voltage of the common power supply line L4 does not drop after turning on the switch of the first priority area again in step S306 (step S307, No), it determines that the first priority area is normal (transient voltage drop) (step S309).

[0077] Moreover, when the controller 3 determines that the voltage of the common power supply line L4 does not recover after turning off the switch of the first priority area in step S303 (step S304, No), the controller 3 moves the process to step S310 shown in FIG.

[0078] In step S310, the controller 3 turns off the switch connected to the power supply line with the second highest priority, i.e., the switch belonging to the second priority area. This separates the second priority area from the power supply circuit. Next, the controller 3 turns on the switch of the first priority area (step S311). This connects at least one of the first power source 10 and the second power source 20 to the common power supply line L4.

[0079] After that, the controller 3 determines whether the voltage of the common power supply line L4 has been restored (step S312). If the controller 3 determines that the voltage has been restored (step S312, Yes), the controller 3 determines that the second priority area has a ground fault or a temporary voltage drop (step S313).

[0080] After a certain time has elapsed, the controller 3 turns on the switch for the second priority area again (step S314) and determines whether the voltage of the common power feed line L4 has dropped (step S315). If the controller 3 determines that the voltage of the common power feed line L4 has dropped (step S315, Yes), it determines that a ground fault has occurred in the second priority area (step S316) and proceeds to step S323.

[0081] Furthermore, if the controller 3 determines that the voltage of the common power supply line L4 does not drop after turning on the switch of the second priority area again in step S314 (step S315, No), it determines that the second priority area is normal (transient voltage drop) (step S317) and proceeds to step S323.

[0082] In addition, if the controller 3 determines that the voltage of the common power supply line L4 does not recover after turning off the switch of the second priority area in step S310 (step S312, No), it determines that the third priority area has a ground fault or a transient voltage drop (step S318).

[0083] Thereafter, the controller 3 waits for a certain period of time (step S319) and determines whether or not the voltage of the common power feed line L4 has dropped (step S320). If the controller 3 determines that the voltage of the common power feed line L4 has dropped (step S320, Yes), it determines that a ground fault has occurred in the third priority area (step S321) and proceeds to step S323. If the controller 3 determines that the voltage of the common power feed line L4 has not dropped (step S320, No), it determines that the third priority area is normal (transient voltage drop) (step S322) and proceeds to step S323.

[0084] After that, in step S323, the controller 3 judges whether or not the third area A3 is confirmed to have a ground fault. When the controller 3 judges that the third area A3 is confirmed to have a ground fault (step S323, Yes), the controller 3 sequentially turns on the third to sixth switches 13 to 16, turns off the remaining switches among the third to sixth switches 13 to 16, and identifies the ground fault location in the third area A3 (step S324). After that, the controller 3 turns off the switches among the third to sixth switches 13 to 16 that are connected to the ground fault load that is the load of the ground fault location, turns on the remaining switches, turns on the first switch 11 and the second switch 12 (step S325), and ends the process. As a result, power is supplied from the first power source 10 and the second power source 20 to the loads among the first to fourth loads 41 to 44 that are not connected to the ground fault location.

[0085] On the other hand, when the controller 3 determines that the third area A3 is not a confirmed ground fault (step S323, No), if there is an area where a ground fault has been confirmed (i.e., the first area A1 or the second area A2 is a confirmed ground fault), it turns off the switch of the area where the ground fault has been confirmed and turns on all other switches (step S326). Also, if there is no area where a ground fault has been confirmed and all areas are normal (transient voltage drop), the controller 3 turns on the switches of all areas A1 to A3 (step S326). After that, the controller ends the process.

[0086] The controller 3 configured to determine whether a voltage drop is a transient voltage drop or a ground fault can perform appropriate power supply control depending on whether the voltage drop on the common power supply line L4 is due to a ground fault or is a transient voltage drop.

[0087] [2. Second embodiment] [2-1. Configuration example of power supply control device according to the second embodiment] Fig. 5 is an explanatory diagram showing a configuration example of a power supply control device 1A according to the second embodiment. As shown in Fig. 5, the power supply control device 1A differs from the power supply control device 1 according to the first embodiment in that it is provided with a bypass circuit 6, but the other configurations are the same as those of the power supply control device 1 according to the first embodiment.

[0088] The bypass circuit 6 is connected in parallel with the second switch 12. The bypass circuit 6 includes a circuit in which a bypass switch 61 and a resistor 62 are connected in series. When turning on the first switch 11 again in order to determine whether the power failure in the first area A1 is a transient power failure or not, the controller 3A according to the second embodiment turns off the second switch 12 and turns on the bypass switch 61.

[0089] At this time, if a ground fault occurs in the first area A1, a current flows from the second power source 20 to the ground fault point via the bypass circuit 6, but the current value is limited by the resistor 62. Therefore, even if a ground fault occurs in the first area A1, the power taken from the second power source 20 can be reduced, and the power of the second power source 20 can be secured.

[0090] Furthermore, when determining whether or not the power failure in the second area A2 is a transient power failure, the controller 3A according to the second embodiment turns off the second switch 12 and turns on the bypass switch 61 while keeping the first switch 11 on. At this time, if a ground fault occurs in the second area A2, a current flows from the first power source 10 to the ground fault point via the bypass circuit 6, but the current value is limited by the resistor 62. Therefore, even if a ground fault occurs in the second area A2, the power taken from the first power source 10 can be reduced, and the power of the first power source 10 can be secured.

[0091] Furthermore, when determining whether or not the power failure in the third area A3 is a transient power failure, the controller 3A according to the second embodiment turns off the second switch 12 and turns on the bypass switch 61. At this time, if a ground fault occurs in the third area A3, a current flows from the second power source 20 to the ground fault point via the bypass circuit 6, but the current value is limited by the resistor 62. Therefore, even if a ground fault occurs in the third area A3, the power taken from the second power source 20 can be reduced, and the power of the second power source 20 can be secured.

[0092] In this way, when determining whether a power failure in a certain area is a transient power failure or not, by turning off the second switch 12 and turning on the bypass switch 61, the power taken from the first power source 10 or the second power source 20 can be reduced and the power of the first power source 10 or the second power source 20 can be secured.

[0093] [2-2. Processing Executed by the Controller According to the Second Embodiment] Next, a process executed by the controller 3A according to the second embodiment will be described below. Figures 6A to 8 are flowcharts showing an example of the process executed by the controller 3A according to the second embodiment.

[0094] 6A, when the vehicle is started, the controller 3A first reads out from a table stored in the memory the priority order of the power supply lines that identify the location of the failure when a power supply failure occurs (step S500). Next, the controller 3 turns on the first to sixth switches 11 to 16 and turns off the bypass switch 61 (step S501). As a result, power is supplied from the first power source 10 and the second power source 20 to the first to fourth loads 41 to 44.

[0095] Next, the controller 3A determines whether or not the voltage of the common power supply line L4 has dropped to a ground fault threshold value or less (step S502). When the controller 3A determines that the voltage of the common power supply line L4 has not dropped (step S502, No), the controller 3A shifts the process to step S501.

[0096] Furthermore, when the controller 3A determines that the voltage of the common power supply line L4 has dropped (step S502, Yes), it turns off the switch connected to the power supply line with the highest priority, that is, the switch belonging to the first priority area (step S503). This separates the first priority area from the power supply circuit.

[0097] At this time, if a ground fault or a transient voltage drop occurs in the first priority area, the controller 3A will no longer detect a power failure because the voltage of the common power supply line L4 will be restored. Also, if a ground fault does not occur in the first area A1, the controller 3A will continue to detect a power failure because the voltage will not be restored.

[0098] Therefore, after turning off the switch of the first priority area in step S503, the controller 3A judges whether the voltage has been restored (step S504). If the controller 3A judges that the voltage has been restored (step S504, Yes), the controller 3A judges that the first priority area has a ground fault or a temporary voltage drop (step S505).

[0099] 6B, the controller 3A judges whether the first priority area is the first area A1 (step S506). If the first priority area is the first area A1 (step S506, Yes), the controller 3A turns off the second switch 12 and turns on the bypass switch 61 (step S507), and turns on the switch of the first priority area, i.e., the first switch 11, again after a certain time (step S508). This causes the first area A1 to be connected to the power supply circuit again. At this time, if the first priority area (i.e., the first area A1) has a ground fault, the voltage of the common power supply line L4 remains low, but if the voltage drop is temporary, the voltage of the common power supply line L4 has returned to normal.

[0100] Therefore, the controller 3A judges whether or not the voltage of the common power feed line L4 has dropped (step S513). When the controller 3A judges that the voltage of the common power feed line L4 has dropped (step S513, Yes), it judges that a ground fault has occurred in the first priority area (step S514) and moves the process to step S541 shown in Fig. 6C. At this time, by turning on the first switch 11 again in step S508, a current flows from the second power source 20 toward the ground fault point in the first priority area, i.e., the first area A1, but the current value is limited by the resistor 62 of the bypass circuit 6. As a result, the power taken out from the second power source 20 is reduced.

[0101] Furthermore, if the controller 3A determines in step S513 that the voltage of the common power supply line L4 does not drop (step S513, No), the controller 3A determines that the first priority area is normal (transient voltage drop) (step S515) and transfers the process to step S541 shown in FIG. 6C.

[0102] Furthermore, when the controller 3A determines in step S506 that the first priority area is not the first area A1 (step S506, No), it determines whether the first priority area is the second area A2 (step S509). If the first priority area is the second area A2 (step S509, Yes), the controller 3A turns on the bypass switch 61 after a certain time (step S510) and performs the ground fault or normality determination in steps S513 to S515. At this time, the first power source 10 is connected to the power supply circuit. Therefore, if a ground fault occurs in the second area A2, a current flows from the first power source 10 to the ground fault point via the bypass circuit 6, but the current value is limited by the resistor 62. This reduces the power taken out from the first power source 10.

[0103] Furthermore, when the controller 3A determines in step 509 that the first priority area is not the second area A2 (step S509, No), that is, when the first priority area is the third area A3, it turns off the second switch 12 and turns on the bypass switch 61 (step S511), and after a certain time, turns on the switches of the first priority area, that is, the third to sixth switches 13 to 16, again (step S512), and performs the ground fault or normality determination in steps S513 to S515. At this time, the first power source 10 is connected to the common power supply line L4, and the second power source 20 is connected via the bypass circuit 6. Therefore, if a ground fault occurs in the third area A3, a current flows from the first power source 10 and the second power source to the ground fault point in the third area A3, but the current value from the second power source is limited by the resistor 62. This reduces the power taken out from the second power source 20.

[0104] When the second switch 12 is turned off and the bypass switch 61 is turned on in step S511, the first switch 11 may be turned off. This makes it possible to eliminate power taken from the first power source 10 when a ground fault occurs in the third area A3.

[0105] Furthermore, when the controller 3A determines that the voltage of the common power supply line L4 does not recover after turning off the switch of the first priority area in step S503 shown in FIG. 6A (step S504, No), the controller 3A moves the process to step S516 shown in FIG. 7. In step S516, the controller 3A turns off the switch connected to the power supply line with the second highest priority, that is, the switch belonging to the second priority area (step S516), and turns on the switch of the first priority area (step S517). This separates the second priority area from the power supply circuit. At this time, at least one of the first power source 10 and the second power source 20 is connected to the common power supply line L4.

[0106] After that, the controller 3A determines whether the voltage of the common power supply line L4 has been restored (step S518). If the controller 3A determines that the voltage has been restored (step S518, Yes), the controller 3A determines that the second priority area has a ground fault or a temporary voltage drop (step S519).

[0107] Next, the controller 3A judges whether the second priority area is the first area A1 (step S520). If the second priority area is the first area A1 (step S520, Yes), the controller 3A turns off the second switch 12 and turns on the bypass switch 61 (step S521), and turns on the switch of the second priority area, i.e., the first switch 11, again after a certain time (step S522). This causes the first area A1 to be connected to the power supply circuit again. At this time, if the second priority area (i.e., the first area A1) has a ground fault, the voltage of the common power supply line L4 remains low, but if the voltage drop is temporary, the voltage of the common power supply line L4 has returned to normal.

[0108] Therefore, the controller 3A judges whether or not the voltage of the common power feed line L4 has dropped (step S527). If the controller 3A judges that the voltage of the common power feed line L4 has dropped (step S527, Yes), it judges that a ground fault has occurred in the second priority area (step S528) and moves the process to step S541 in Fig. 6C. If the controller 3A judges that the voltage of the common power feed line L4 has not dropped (step S527, No), it judges that the second priority area is normal (transient voltage drop) (step S529) and moves the process to step S541 in Fig. 6C.

[0109] Furthermore, if the controller 3A determines in step S520 that the second priority area is not the first area A1 (step S520, No), it determines whether the second priority area is the second area A2 (step S523). If the second priority area is the second area A2 (step S523, Yes), the controller 3A turns on the bypass switch 61 after a certain time (step S524), performs a ground fault or normality determination in steps S527 to S529, and proceeds to step S541 in FIG. 6C.

[0110] Furthermore, if the controller 3A determines in step 523 that the second priority area is not the second area A2 (step S523, No), that is, if the second priority area is the third area A3, it turns off the second switch 12 and turns on the bypass switch 61 (step S525), and after a certain period of time, turns on the switches in the second priority area, that is, the third to sixth switches 13 to 16 again (step S526), ​​and performs a ground fault or normality determination in steps S527 to S529, and then moves the process to step S541 in FIG. 6C.

[0111] Moreover, when the controller 3A determines in step S518 of Fig. 7 that the voltage of the common power supply line L4 has not recovered (step S518, No), the controller 3A shifts the process to step S530 shown in Fig. 8. In this case, it determines that the third priority area has a ground fault or a temporary voltage drop (step S530).

[0112] Next, the controller 3A judges whether the third priority area is the first area A1 (step S531). If the third priority area is the first area A1 (step S531, Yes), the controller 3A turns off the second switch 12 and turns on the bypass switch 61 (step S532), and turns on the switch of the third priority area, i.e., the first switch 11, again after a certain time (step S533). This causes the first area A1 to be connected to the power supply circuit again. At this time, if the third priority area (i.e., the first area A1) has a ground fault, the voltage of the common power supply line L4 remains low, but if the voltage drop is temporary, the voltage of the common power supply line L4 has returned to normal.

[0113] Therefore, the controller 3A judges whether or not the voltage of the common power feed line L4 has dropped (step S538). When the controller 3A judges that the voltage of the common power feed line L4 has dropped (step S538, Yes), the controller 3A judges that a ground fault has occurred in the third priority area (step S539) and moves the process to step S541 in Fig. 6C. When the controller 3A judges that the voltage of the common power feed line L4 has not dropped (step S538, No), the controller 3A judges that the third priority area is normal (transient voltage drop) and moves the process to step S541 in Fig. 6C.

[0114] Furthermore, if the controller 3A determines in step S531 that the third priority area is not the first area A1 (step S531, No), it determines whether the third priority area is the second area A2 (step S534). If the third priority area is the second area A2 (step S534, Yes), the controller 3A turns on the bypass switch 61 after a certain time (step S535), performs a ground fault or normality determination in steps S538 to S540, and proceeds to step S541 in FIG. 6C.

[0115] Furthermore, if the controller 3A determines in step 534 that the third priority area is not the second area A2 (step S534, No), that is, if the third priority area is the third area A3, it turns off the second switch 12 and turns on the bypass switch 61 (step S536), and after a certain period of time, turns on the switches in the third priority area, that is, the third to sixth switches 13 to 16 again (step S537), and performs a ground fault or normality determination in steps S538 to S540, and then proceeds to step S541 in FIG. 6C.

[0116] As described above, when the controller 3A detects a voltage drop in step S502, by the processes of steps S503 to S540, if the voltage drop is a transient voltage drop, it determines that it is normal, and if it is a ground fault, it identifies the ground fault area.

[0117] After that, in step S541 of FIG. 6C, the controller 3A judges whether or not the third area A3 is confirmed to have a ground fault. When the controller 3A judges that the third area A3 is confirmed to have a ground fault (step S541, Yes), the controller 3A sequentially turns on the third to sixth switches 13 to 16, turns off the remaining switches among the third to sixth switches 13 to 16, and identifies the ground fault location in the third area A3 (step S542). After that, the controller 3A turns off the switches among the third to sixth switches 13 to 16 that are connected to the ground fault load that is the load of the ground fault location, turns on the remaining switches, turns on the first switch 11 and the second switch 12, and turns off the bypass switch 61 (step S543), and ends the process. As a result, power is supplied from the first power source 10 and the second power source 20 to the loads not connected to the ground fault location among the first to fourth loads 41 to 44.

[0118] On the other hand, when the controller 3A determines in step S541 that the third area A3 is not confirmed to have a ground fault (step S541, No), it determines whether or not the first area A1 is confirmed to have a ground fault (step S544). When the controller 3A determines that the first area A1 is confirmed to have a ground fault (step S544, Yes), the controller 3A turns off the first switch 11, turns on the second switch 12, turns off the bypass switch 61, and turns on the third to sixth switches 13 to 16 (step S545), and ends the process. As a result, power is supplied from the second power source 20 to the first to fourth loads 41 to 44.

[0119] Furthermore, when the controller 3A determines in step S544 that the first area A1 is not confirmed to have a ground fault (step S544, No), it determines whether or not the second area A2 is confirmed to have a ground fault (step S546). When the controller 3A determines that the second area A2 is confirmed to have a ground fault (step S546, Yes), the controller 3A turns on the first switch 11, turns off the second switch 12, turns off the bypass switch 61, and turns on the third to sixth switches 13 to 16 (step S547), and ends the process. As a result, power is supplied from the first power source 10 to the first to fourth loads 41 to 44.

[0120] Furthermore, when it is determined in step S546 that the second area A2 is not definitely a ground fault (step S546, No), that is, when there is no ground fault and the area is normal, the controller 3A turns on the first switch 11, turns on the second switch 12, turns off the bypass switch 61, and turns on the third to sixth switches 13 to 16 (step S548), and ends the process. As a result, power is supplied from the first power source 10 and the second power source 20 to the first to fourth loads 41 to 44.

[0121] [3. Third embodiment] In the first and second embodiments, a fixed priority order is set in advance for each power supply line, but the priority order according to the embodiments may be modified as appropriate. That is, the controller 3, 3A according to the third embodiment may be configured to modify the priority order set for the first power supply line L1, the second power supply line L2, and the load power supply line L3. Hereinafter, the controller 3, 3A that modifies the priority order will be described with reference to Figs. 9 and 10. Figs. 9 and 10 are flowcharts showing an example of a process executed by the controller 3, 3A according to the third embodiment.

[0122] [3-1. Setting priorities based on the number of times ground faults occur] For example, the controller 3, 3A counts the number of occurrences of power failures for each location where the power failures occur, and sets the priority of the power supply line that has the most frequent occurrences of power failures among the first power supply line L1, the second power supply line L2, and the load power supply line L3 to be higher than the priority of the other power supply lines.

[0123] In this case, in parallel with the process of identifying the ground fault location, the controller 3, 3A executes the process shown in Fig. 9. Specifically, as shown in Fig. 9, the controller 3, 3A first determines whether the location of the ground fault has been determined (step S601).

[0124] The controller 3, 3A includes an area counter for the ground fault area, and when it is determined that the location of the ground fault has been determined (Yes in step S601), the area counter for the ground fault area is incremented by 1 (step S602).

[0125] Specifically, the area counter of the area (the first area A1, the second area A2, or the third area A3) connected to the power supply line in which the occurrence of a ground fault has been confirmed among the first power supply line L1, the second power supply line L2, and the load power supply line L3 is incremented by 1. After that, the controller 3, 3A shifts the process to step S603.

[0126] If the controller 3, 3A determines that the location of the ground fault has not been determined (step S601, No), the controller 3, 3A moves the process to step S603. In step S603, the controller 3, 3A modifies the priority order, that is, the table that stores the priority order, according to the value of the area counter.

[0127] That is, the controller 3, 3A modifies the priority order in the table so that the power supply line included in the area with the larger area counter value among the first area A1, the second area A2, and the third area A3 has a higher priority. After that, the controller 3, 3A starts the process again from step S601.

[0128] In this way, the controllers 3, 3A can start the process of identifying the location of the ground fault from the power supply line that is most likely to have a ground fault by following the priority order updated each time the location of the ground fault is determined. As a result, the controllers 3, 3A can identify the location of the ground fault earlier than when the priority order is not updated.

[0129] [3-2. Correcting priorities based on information from other vehicles] For example, the controller 3, 3A receives information on the location of the power supply failure from another vehicle. Then, the controller 3, 3A sets the priority of the power supply line that is the same as the power supply line that has had a large number of occurrences in the other vehicle among the first power supply line L1, the second power supply line L2, and the load power supply line L3 of the own vehicle to be higher than the priority of the other power supply lines.

[0130] In this case, the controller 3, 3A executes the process shown in Fig. 10 in parallel with the process of identifying the ground fault location. The controller 3, 3A includes a communication interface capable of communicating information with other vehicles, and an area counter for the ground fault area.

[0131] 10, the controller 3, 3A first receives information on the ground fault area from another vehicle (step S701). That is, the controller 3, 3A receives information on the location where the power supply failure has occurred from the other vehicle.

[0132] Next, the controller 3, 3A increments the area counter of the ground fault area of ​​the host vehicle by 1 based on the ground fault area information received from the other vehicle (step S702). That is, the controller 3, 3A increments the area counter of the area of ​​the host vehicle (first area A1, second area A2, and third area A3) that includes the same power supply line as the power supply line in which the occurrence of a ground fault has been confirmed in the other vehicle by 1.

[0133] Thereafter, the controller 3, 3A modifies the priority order, i.e., the table storing the priority order, according to the value of the area counter (step S703). That is, the controller 3, 3A modifies the priority order in the table so that the power supply line included in the area with the larger value of the area counter among the first area A1, the second area A2, and the third area A3 has a higher priority order.

[0134] Specifically, the controller 3, 3A sets the priority of the power feed line that is the same as the power feed line that has a high occurrence count in the other vehicle among the first power feed line L1, the second power feed line L2, and the load power feed line L3 of the host vehicle to be higher than the priority of the other power feed lines. After that, the controller 3, 3A starts the process again from step S701.

[0135] Thus, the controller 3, 3A can start the process of identifying the location of the ground fault from the power supply line that is more likely to have a ground fault by following the priority order that is updated every time information on the ground fault area is received from another vehicle. As a result, the controller 3, 3A can identify the location of the ground fault earlier than when the priority order is not updated. The controller 3, 3A may be configured to execute the process shown in FIG. 9 and the process shown in FIG. 10 in parallel.

[0136] The controllers 3, 3A may receive information on the location of the power failure from a server, rather than directly from the other vehicles. In this case, the server may aggregate the information from the other vehicles and modify the priority table by performing the process shown in FIG. 10. The server transmits the modified table to the controllers 3, 3A. The controllers 3, 3A replace the currently stored table indicating the priority with the table received from the server. As a result, the controllers 3, 3A receive the modified table from the server, and therefore communication charges can be reduced compared to receiving the information from the other vehicles individually.

[0137] [4. Modifications] In the above embodiment, the area including the first to fourth loads 41 to 44 and the load power supply line L3 is defined as the third area A3, but the third area A3 according to the embodiment may be divided into multiple areas. For example, the area including the first to second loads 41 to 42 and the power supply line connected to the first to second loads 41 to 42 may be defined as the 3-1 area, and the area including the third to fourth loads 43 to 44 and the power supply line connected to the third to fourth loads 43 to 44 may be defined as the 3-2 area. In this case, it is preferable to divide the area into important loads necessary for autonomous driving and loads that are not directly involved in autonomous driving.

[0138] In this case, the priority order is set for the 3-1 area and the 3-2 area separately. The number of divided areas into which the 3rd area A3 is divided is arbitrary. This allows the controllers 3, 3A to set an appropriate priority order for each divided area, thereby enabling the location of the ground fault in the 3rd area A3 to be identified more quickly.

[0139] [5. Notes] As an appendix, the features of the present invention are as follows: (1) a common power supply line connecting a first power supply line connected to a first power supply, a second power supply line connected to a second power supply, and a load power supply line connected to a load; a switch that connects the first power supply line and the common power supply line; a switch that connects the second power supply line and the common power supply line; a switch connecting the load power supply line and the common power supply line; a sensor provided on the common power supply line for detecting a power supply state; a controller that, when detecting a power failure based on an output of the sensor, turns off the switch in accordance with a priority order set for the first power supply line, the second power supply line, and the load power supply line, and identifies a location where the power failure has occurred based on the output of the sensor; A power supply control device comprising: (2) The priority order is preset. The power supply control device according to (1) above. (3) The controller: Counting the number of occurrences of the power failure for each of the occurrence locations; The priority of the power supply line having a higher occurrence frequency among the first power supply line, the second power supply line, and the load power supply line is set to be higher than the priority of the other power supply lines. The power supply control device according to (1) or (2). (4) The controller: receiving information about a location of the power failure from another vehicle; Among the first power supply line, the second power supply line, and the load power supply line of the host vehicle, the priority of the power supply line that is the same as the power supply line in which the number of occurrences of the power supply failure in the other vehicle is set to be higher than the priority of the other power supply lines. The power supply control device according to any one of (1) to (3). (5) When an area including the first power source and the first power supply line is defined as a first area, an area including the second power source and the second power supply line is defined as a second area, and an area including the load and the load power supply line is defined as a third area, The controller: all of the switches are turned on during normal operation when the power failure is not detected; Among the first area, the second area, and the third area, an area connected to the switch that detects the power failure and is turned off so that the power failure is no longer detected is identified as a location where the power failure has occurred. The power supply control device according to any one of (1) to (4). (6) The controller: turning off the switch connected to the power supply line having the first priority among the first power supply line, the second power supply line, and the load power supply line; If the power failure is continuously detected, turning off the switch connected to the power supply line having the second priority; If the power failure is no longer detected, an area including the power supply line having the second priority among the power supply lines included in the first area, the second area, and the third area is identified as a location where the power failure has occurred; If the power failure continues to be detected, an area including the remaining power supply lines is identified as the location where the power failure occurred. The power supply control device according to (5) above. (7) The controller: When a power failure is detected, the switch that was turned off is turned on again to determine whether the power failure is a temporary power failure or not. The power supply control device according to any one of (1) to (6). (8) a bypass circuit connected in parallel with a switch that connects the second power supply line and the common power supply line, the bypass circuit including a bypass switch and a resistor connected in series; Further equipped with The controller: When the switch connecting the first power supply line and the common power supply line is turned on again in order to determine whether the power supply failure is a transient power supply failure, the switch connecting the second power supply line and the common power supply line is turned off and the bypass switch is turned on. The power supply control device according to (7) above. (9) The controller: When the switch connecting the second power supply line and the common power supply line is turned on again in order to determine whether the power supply failure is a transient power supply failure, the switch connecting the second power supply line and the common power supply line is turned off and the bypass switch is turned on. The power supply control device according to (8). (10) a common power supply line connecting a first power supply line connected to a first power supply, a second power supply line connected to a second power supply, and a load power supply line connected to a load; a switch that connects the first power supply line and the common power supply line; a switch that connects the second power supply line and the common power supply line; a switch connecting the load power supply line and the common power supply line; a sensor provided on the common power supply line for detecting a power supply state; A controller of a power supply control device comprising: When a power failure is detected based on the output of the sensor, the switch is turned off in accordance with a priority order set for the first power supply line, the second power supply line, and the load power supply line, and a procedure is executed to identify the location of the power failure based on the output of the sensor. Power control program.

[0140] Further advantages and modifications may readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and equivalents thereof. [Explanation of symbols]

[0141] 1,1A Power Control Device 3,3A Controller 5 Sensors 6 Bypass Circuit 61 Bypass Switch 62 Resistance 10 1st power supply 11 First Switch 12 Second Switch 13 Third Switch 14 4th Switch 15 5th Switch 16 6th Switch 20 2nd power supply 41 1st load 42 2nd load 43 Third load 44 4th load A1 1st Area A2 2nd Area A3 Third Area L1 First power supply line L2 Second power supply line L3 Load supply line L4 Common power supply line

Claims

1. a common power supply line connecting a first power supply line connected to a first power source, a second power supply line connected to a second power source, and a load power supply line connected to a load; a switch that connects the first power supply line and the common power supply line; a switch that connects the second power supply line and the common power supply line; a switch connecting the load power supply line and the common power supply line; a sensor provided on the common power supply line for detecting a power supply state; a controller that, when detecting a power supply failure based on an output of the sensor, turns off the switch in accordance with a priority order set for the first power supply line, the second power supply line, and the load power supply line, and identifies a location where the power supply failure has occurred based on the output of the sensor; A power supply control device comprising:

2. The priority order is preset. The power supply control device according to claim 1 .

3. The controller: Counting the number of occurrences of the power failure for each of the occurrence locations; The priority of the power supply line having a higher occurrence frequency among the first power supply line, the second power supply line, and the load power supply line is set to be higher than the priority of the other power supply lines. The power supply control device according to claim 1 .

4. The controller: receiving information about a location of the power failure from another vehicle; Among the first power supply line, the second power supply line, and the load power supply line of the host vehicle, the priority of the power supply line that is the same as the power supply line in which the number of occurrences of the power supply failure in the other vehicle is set to be higher than the priority of the other power supply lines. The power supply control device according to claim 1 .

5. When an area including the first power source and the first power supply line is defined as a first area, an area including the second power source and the second power supply line is defined as a second area, and an area including the load and the load power supply line is defined as a third area, The controller: all of the switches are turned on during normal operation when the power failure is not detected; Among the first area, the second area, and the third area, an area connected to the switch that detects the power failure and is turned off so that the power failure is no longer detected is identified as a location where the power failure has occurred. The power supply control device according to claim 1 .

6. The controller: turning off the switch connected to the power supply line having the first priority among the first power supply line, the second power supply line, and the load power supply line; If the power failure is continuously detected, turning off the switch connected to the power supply line having the second priority; If the power failure is no longer detected, an area including the power supply line having the second priority among the power supply lines included in the first area, the second area, and the third area is identified as a location where the power failure has occurred; If the power failure is continuously detected, an area including the remaining power supply lines is identified as the location where the power failure occurred. The power supply control device according to claim 5.

7. The controller: When a power failure is detected, the switch that was turned off is turned on again to determine whether the power failure is a temporary power failure or not. The power supply control device according to claim 1 .

8. a bypass circuit connected in parallel with a switch that connects the second power supply line and the common power supply line, the bypass circuit including a bypass switch and a resistor connected in series; Further equipped with The controller: When the switch connecting the first power supply line and the common power supply line is turned on again in order to determine whether the power supply failure is a temporary power supply failure, the switch connecting the second power supply line and the common power supply line is turned off and the bypass switch is turned on. The power supply control device according to claim 7.

9. The controller: When the switch connecting the second power supply line and the common power supply line is turned on again in order to determine whether the power supply failure is a temporary power supply failure, the switch connecting the second power supply line and the common power supply line is turned off and the bypass switch is turned on. The power supply control device according to claim 8.

10. a common power supply line connecting a first power supply line connected to a first power source, a second power supply line connected to a second power source, and a load power supply line connected to a load; a switch that connects the first power supply line and the common power supply line; a switch that connects the second power supply line and the common power supply line; a switch connecting the load power supply line and the common power supply line; a sensor provided on the common power supply line for detecting a power supply state; A controller of a power supply control device comprising: When a power failure is detected based on the output of the sensor, the switch is turned off in accordance with a priority order set for the first power supply line, the second power supply line, and the load power supply line, and a procedure is executed to identify the location of the power failure based on the output of the sensor. Power control program.

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