Power supply control device and control method
The power control device extends backup load operation time by managing power distribution between multiple power systems, using a second power source with higher charge state to supply power to backup loads during system abnormalities.
Patent Information
- Application Number
- JP2021207806
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-12-22
- Publication Date
- 2026-05-18
- Estimated Expiration
- 2041-12-22
AI Technical Summary
When an abnormality occurs in one of multiple power systems, the power supply to backup loads from other systems is insufficient, leading to a shortened operation time.
A power control device with a first and second power system, load switches, and a control unit that manages power distribution to extend backup load operation time by utilizing a second power source with higher charge state to supply power to backup loads.
The solution extends the operating time of backup loads by intelligently switching power distribution based on the charge state of the second power source, ensuring continued operation during system abnormalities.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to a technique for supplying power from a plurality of power systems.
Background Art
[0002] Conventionally, when an abnormality occurs in some of a plurality of power systems, a power supply system that supplies power to a backup load from other power systems is known (see, for example, Patent Document 1).
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] However, when the storage capacity of the power supply that supplies power by other power systems is low, the power that can be supplied to the backup load by other power systems is insufficient, and the operation time of the backup load by other power systems may be shortened.
[0005] The present invention has been made in view of the above, and an object thereof is to provide a power control device and a control method for lengthening the operation time of a backup load.
Means for Solving the Problems
[0006] A power control device according to one embodiment comprises a first system, a second system, a plurality of load switches, and a control unit. The first system is capable of supplying power from a first power source to a first load group. The second system is capable of supplying power from a second power source to a second load group. The plurality of load switches can switch the power supply to each load in the first load group and the second load group, respectively. In a predetermined backup state, the control unit controls the plurality of load switches so that power is supplied from the second power source to backup loads included in at least one of the first load group and the second load group. The control unit detects the charge state of the second power source. In a predetermined backup state, the control unit increases the number of connected load switches as the charge state increases. [Effects of the Invention]
[0007] According to one embodiment, the operating time of the backup load can be extended. [Brief explanation of the drawing]
[0008] [Figure 1] Figure 1 is an explanatory diagram showing an example of the configuration of a power supply control device according to an embodiment. [Figure 2] Figure 2 shows the power supply from the first power source. [Figure 3] Figure 3 shows the power supply when a ground fault occurs in the first power system and the second power source is in the first charging state. [Figure 4] Figure 4 shows the power supply when a ground fault occurs in the first power system and the second power source is in the second charging state. [Figure 5] Figure 5 shows the relationship between the charging status of the second power supply, the feasibility of automatic operation control, and fail-safe control. [Figure 6] Figure 6 shows the power supply when the start switch is OFF and the second power supply is in the fourth charging state. [Figure 7] Figure 7 shows the power supply when the start switch is OFF and the second power supply is in the fifth charging state. [Figure 8] Figure 8 shows the state of each switch when the start switch is OFF and the charging state of the second power supply is the sixth charging state. [Figure 9] Figure 9 shows the relationship between the charge state of the second power source and the power supply when the start switch is OFF. [Figure 10] Figure 10 is a flowchart illustrating the fail-safe procedure in the event of a ground fault in the first system. [Figure 11] Figure 11 is a flowchart illustrating the standby process when the start switch is OFF. [Modes for carrying out the invention]
[0009] Embodiments of the power control device and control method will be described in detail below with reference to the attached drawings. However, the present invention is not limited to the embodiments described below. In the following description, a power control device that supplies power to a load and is mounted on a vehicle equipped with an autonomous driving function will be used as an example; however, the power control device according to the embodiment may be mounted on a vehicle that does not have an autonomous driving function. Furthermore, the power control device according to the embodiment may be mounted on a vehicle or other object.
[0010] Furthermore, the following description will focus on the case where the vehicle equipped with the power control device is an electric vehicle or a hybrid vehicle, but the vehicle equipped with the power control device may also be an engine-powered vehicle that runs on an internal combustion engine.
[0011] Figure 1 is an explanatory diagram showing an example of the configuration of a power control device 1 according to an embodiment. The power control device 1 according to this embodiment is connected to a first power supply 10, a first load group 100, a second load group 110, an automatic operation control device 120, and a start switch 130.
[0012] The first power supply 10 includes a DC / DC converter 11 (hereinafter referred to as "DC / DC 11") and a lead battery 12 (hereinafter referred to as "PbB 12"). Note that the battery of the first power supply 10 may be any secondary battery other than PbB 12. The first power supply 10 is a main power supply that mainly supplies power to the first load group 100, the second load group 110, and the like.
[0013] DC / DC 11 is connected to a generator that converts the regenerative energy of the vehicle into electric power for power generation, and transforms and outputs the input voltage input from the generator. The generator may be an alternator that converts the rotational force of the engine into electric power for power generation when the vehicle includes an engine. DC / DC 11 performs charging of PbB 12, power supply to the first load group 100, power supply to the second load group 110, and charging of the second power supply 20 described later.
[0014] The first load group 100 includes a first load 101, a second load 102, and a third load 103. The first load 101 includes devices used when autonomous driving is executed. The first load 101 includes a steering motor, an electric brake device, an in-vehicle camera, a radar, etc. that operate during autonomous driving.
[0015] The second load 102 includes devices that are not related to the execution of autonomous driving. The second load 102 includes devices that operate even when the vehicle is parked and the start switch 130 of the vehicle's power supply system is turned off. The second load 102 includes a door lock control ECU that controls the locking of the vehicle's doors. When the in-vehicle camera is a camera that captures the surroundings of the vehicle with the start switch 130 off, the second load 102 includes the in-vehicle camera.
[0016] The third load 103 includes devices that are not related to the execution of autonomous driving. The third load 103 includes in-vehicle power outlets, external power outlets, etc.
[0017] The second load 102 and the third load 103 are standby loads that can operate when the start switch 130 is OFF. The second load 102 and the third load 103 are also backup loads. Priorities are assigned to the second load 102 and the third load 103. The priority of the second load 102 is higher than the priority of the third load 103. The respective priorities of the second load 102 and the third load 103 are stored in the storage area of the power control device 1.
[0018] The second load group 110 includes the fourth load 111 and the fifth load 112. Similar to the first load 101, the fourth load 111 is a load used when automatic driving is executed. The fourth load 111 is a drive system load such as a steering motor and an electric brake device. The fourth load 111 is a backup load that executes fail-safe control of automatic driving control when a ground fault occurs in the first system 200 described later.
[0019] The fifth load 112 is a load used when automatic driving is executed. The fifth load 112 is a recognition system load such as an in-vehicle camera and a radar. The fifth load 112 is a backup load that executes fail-safe control of automatic driving control when a ground fault occurs in the first system 200 described later.
[0020] The fourth load 111 and the fifth load 112 are backup loads that can be operated by power supplied from the second power supply 20 when a ground fault occurs in the first system 200 described later. Priorities are assigned to the fourth load 111 and the fifth load 112. The priority of the fourth load 111 is higher than the priority of the fifth load 112. The respective priorities of the fourth load 111 and the fifth load 112 are stored in the storage area of the power control device 1.
[0021] The automatic driving control device 120 is a control device that operates the first load 101 of the first load group 100 and the second load group 110 (fourth load 111 and fifth load 112) to control the vehicle automatically. The automatic driving control device 120 can also perform fail-safe control of the automatic driving control by operating either the first load 101 or the second load group 110. If a ground fault occurs in the first system 200 or the second system 210, which will be described later, the automatic driving control device 120 will perform fail-safe control of the automatic driving control using the system that does not have a ground fault. Fail-safe control of the automatic driving control is a control that moves the vehicle to a safe location by automatic driving.
[0022] The start switch 130 is a switch that turns the power system ON or OFF. The start switch 130 may also be an ignition switch or an ACC (accessory) switch.
[0023] The power control device 1 is supplied with power from an externally located first power supply 10. The power control device 1 can supply the power supplied from the externally located first power supply 10 to the first load group 100, the second load group 110, and the second power supply 20, which will be described later.
[0024] The power control device 1 comprises a first system 200 and a second system 210. The first system 200 is a system capable of supplying power from the first power source 10 to the first load group 100. The second system 210 is a system capable of supplying power from the second power source 20 (described later) to the second load group 110 (described later).
[0025] The first system 200 includes a first line 201 that connects the first power supply 10 and the first load group 100. The first line 201 is connected to each of the loads 101 to 103 of the first load group 100, respectively.
[0026] The second system 210 includes a second line 211 that connects the second power supply 20 and the second load group 110. The second line 211 is connected to each load 111 and 112 of the second load group 110, respectively. The first line 201 and the second line 211 are connected by a connecting line 220.
[0027] The power control device 1 comprises a second power supply 20, a DC / DC converter 30, a plurality of switches 40 to 48, a first voltage sensor 50, a second voltage sensor 51, and a control unit 60.
[0028] The second power supply 20 includes, for example, a lithium-ion battery 21 (hereinafter referred to as "LiB21"). The second power supply 20 is selected to have a higher voltage than the first power supply 10 so that the minimum necessary voltage can be supplied even at low temperatures. The second power supply 20 is a backup power supply in case the power supply from the first power supply 10 becomes unavailable. Note that the battery of the second power supply 20 may be any secondary battery other than LiB21.
[0029] The DC / DC converter 30 (hereinafter referred to as "DC / DC30") is controlled by the control unit 60 and, when charging the LiB21, transforms the input voltage received from the first power supply 10 and outputs it. When the LiB21 is not being charged, the DC / DC30 is in a non-operating state.
[0030] The multiple switches 40-48 include a first battery switch 40, a second battery switch 41, a backup switch 42, an inter-system switch 43, and first load switches 44-5th load switches 48. The first battery switch 40 is provided on a first line 201 that can connect the first power supply 10 and the first load group 100.
[0031] The first battery switch 40 is a switch that connects or disconnects the first power supply 10 to the first system 200, and is a switch that switches whether or not power is supplied from the first power supply 10. When the first battery switch 40 is turned ON, both ends of the first battery switch 40 are electrically connected. When the first battery switch 40 is turned OFF, the electrical connection between both ends of the first battery switch 40 is disconnected, or interrupted. The same applies to the second battery switches 41 to the fifth load switches 48.
[0032] The second battery switch 41 is located on the second line 211, which is connected to the second power supply 20 and the second load group 110. The second battery switch 41 is a switch that connects or disconnects the second power supply 20 to the second system 210, and is a switch that switches whether or not power is supplied to the second power supply 20, or whether or not power is supplied from the second power supply 20.
[0033] The backup switch 42 is provided on the second line 211. The backup switch 42 is provided in parallel with the DC / DC 30. When the backup switch 42 is ON, current does not flow to the DC / DC 30 but flows to the backup switch 42. When the backup switch 42 is OFF, current flows to the DC / DC 30. In other words, the backup switch 42 is a switch that switches whether or not current flows through the DC / DC 30.
[0034] The inter-system switch 43 is provided on the connecting line 220 that connects the first line 201 and the second line 211. The inter-system switch 43 is a switch that can connect and disconnect the first line 201 and the second line 211. In other words, the inter-system switch 43 is a switch that connects or disconnects the first system 200 and the second system 210.
[0035] The first load switch 44 is located on the first line 201. The first load switch 44 is a switch that switches whether or not to supply power to the first load 101.
[0036] The second load switch 45 is located on the first line 201. The second load switch 45 is a switch that switches whether or not to supply power to the second load 102.
[0037] The third load switch 46 is located on the first line 201. The third load switch 46 is a switch that switches whether or not to supply power to the third load 103.
[0038] The fourth load switch 47 is located on the second line 211. The fourth load switch 47 is a switch that switches whether or not to supply power to the fourth load 111.
[0039] The fifth load switch 48 is located on the second line 211. The fifth load switch 48 is a switch that switches whether or not to supply power to the fifth load 112.
[0040] The first load switch 44 to the fifth load switch 48 are load switches that can switch whether or not to supply power to each of the loads 101, 102, 103, 111, and 112 of the first load group 100 and the second load group 110, respectively.
[0041] The first voltage sensor 50 is provided on the connection line 220. Specifically, the first voltage sensor 50 is provided on the connection line 220 between the inter-system switch 43 and the first line 201. The first voltage sensor 50 detects the voltage of the first system 200. The second voltage sensor 51 is provided on the connection line 220. Specifically, the second voltage sensor 51 is provided on the connection line 220 between the inter-system switch 43 and the second line 211. The second voltage sensor 51 detects the voltage of the second system 210.
[0042] The control unit 60 includes a microcomputer with a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and various circuits. The control unit 60 may also be composed of hardware such as an ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array).
[0043] The control unit 60 includes a detection unit 61 that functions by the CPU executing a program stored in ROM using RAM as a working area, and a switch setting unit 62, and controls the operation of the power control device 1. The control unit 60 operates by receiving power from the first power supply 10 and the second power supply 20. In other words, the control unit 60 can operate by receiving power from either the first power supply 10 or the second power supply 20. The functions of the detection unit 61 and the switch setting unit 62 may be divided into multiple units.
[0044] The control unit 60 controls multiple load switches so that, in a predetermined backup state, power is supplied from the second power supply 20 to backup loads included in at least one of the first load group 100 and the second load group 110. Specifically, in a predetermined backup state, the control unit 60 increases the number of connected load switches as the charge level of the second power supply 20 increases.
[0045] The detection unit 61 detects that a predetermined backup state is in place. The predetermined backup state includes a state in which a power failure has occurred in the first system 200. The predetermined backup state also includes a state in which the start switch 130 is OFF.
[0046] A power failure is, for example, a ground fault. That is, the detection unit 61 detects that a ground fault has occurred in the first system 200. The detection unit 61 determines whether the voltage detected by the first voltage sensor 50 is within the normal range when the first battery switch 40 and the inter-system switch 43 are ON and the backup switch 42 is OFF. The normal range is the range indicated by the voltage detected by the first voltage sensor 50 when no power failure has occurred in the first system 200. For example, the normal range is the range in which the voltage detected by the first voltage sensor 50 is equal to or greater than a predetermined voltage set in advance.
[0047] The detection unit 61 detects that a ground fault has occurred in the first system 200 when, under normal conditions, the voltage detected by the first voltage sensor 50 is outside the normal range, for example, when the voltage is lower than a predetermined voltage.
[0048] The detection unit 61 detects that no ground fault has occurred in the first system 200 when the voltage detected by the first voltage sensor 50 is within the normal range under normal conditions.
[0049] Furthermore, the detection unit 61 can detect the occurrence of a power failure in the second system 210 based on the voltage detected by the second voltage sensor 51 when the system is functioning normally.
[0050] The detection unit 61 determines whether the start switch 130 is ON or OFF based on the signal obtained from the start switch 130.
[0051] The detection unit 61 acquires voltage information of the second power supply 20 measured by a measuring device provided on the second power supply 20 and detects the charge state of the second power supply 20. Specifically, the detection unit 61 detects the State of Charge (SOC) of the second power supply 20. In addition to voltage information, the detection unit 61 may also acquire current information and temperature information and use the current information, etc., to detect the charge state of the second power supply 20. The detection unit 61 periodically detects the charge state of the second power supply 20 when the vehicle is started and when the start switch 130 is turned ON, and during subsequent operation.
[0052] When the detection unit 61 detects the charging state of the second power supply 20, it determines whether the charging state of the second power supply 20 is the first charging state. The first charging state is a state in which the energy storage capacity of the LiB 21 is equal to or greater than a first predetermined capacity. The first predetermined capacity is a preset value. The first predetermined capacity is the capacity that allows the fourth load 111 and the fifth load 112 of the second load group 110 to perform fail-safe control of the automatic operation control in the event of a ground fault in the first system 200 during automatic operation. The first predetermined capacity is, for example, 50% of the fully charged energy storage capacity. When the detection unit 61 determines that the charging state of the second power supply 20 is the first charging state, it permits automatic operation.
[0053] When the detection unit 61 detects the charge state of the second power supply 20, it determines whether the charge state of the second power supply 20 is the second charge state. The second charge state is a state in which the storage capacity of the LiB 21 is less than the first predetermined capacity and greater than or equal to the second predetermined capacity. The second predetermined capacity is a preset value and is smaller than the first predetermined capacity. In other words, the charge state of the second charge state is lower than that of the first charge state. The second predetermined capacity is a capacity at which, if a ground fault occurs in the first system 200 during automatic operation, operating the fifth load 112 may not be possible until the fail-safe control of the automatic operation control by the fourth load 111 is terminated, that is, until the vehicle stops. The second predetermined capacity is, for example, 30% of the fully charged storage capacity. When the detection unit 61 determines that the charge state of the second power supply 20 is the second charge state, it permits automatic operation.
[0054] When the detection unit 61 detects the charging state of the second power supply 20, it determines whether the charging state of the second power supply 20 is the third charging state. The third charging state is a state in which the energy storage capacity of the LiB 21 is less than the second predetermined capacity. In the third charging state, even if only the fourth load 111 is being driven, the system cannot be operated until the fail-safe control of the automatic driving control is terminated, that is, until the vehicle stops, in the event of a ground fault in the first system 200 during automatic driving. Therefore, if the detection unit 61 determines that the charging state of the second power supply 20 is the third charging state, it prohibits automatic driving.
[0055] When the detection unit 61 detects the charging state of the second power supply 20 while the vehicle is in operation, it detects whether the charging state of the second power supply 20 is in the first, second, or third charging state, and determines whether automatic operation is permitted according to the result. Specifically, during manual operation after the start switch 130 is turned ON, if the detection unit 61 determines that the charging state of the second power supply 20 is in the first or second charging state, it permits automatic operation; if it is in the third charging state, it prohibits automatic operation. When automatic operation is started after the detection unit 61 has permitted automatic operation, the detection unit 61 continues to detect the charging state of the second power supply 20, and also continues to detect the charging state of the second power supply 20 even after a ground fault is detected during automatic operation. If a ground fault is detected in the first system 200 during automatic operation, the switches 40 to 48 described later are controlled according to the charging state of the second power supply 20 at that time.
[0056] The detection unit 61 determines whether the vehicle is in autonomous driving mode. The detection unit 61 determines whether autonomous driving is being performed by the autonomous driving control device 120.
[0057] Furthermore, when the start switch 130 is turned OFF, the detection unit 61 also detects the charging status of the second power supply 20 during that OFF period.
[0058] Specifically, when the start switch 130 is OFF, the detection unit 61 determines whether the charging state of the second power supply 20 is the fourth charging state. The fourth charging state is a state in which the storage capacity of the LiB 21 is equal to or greater than the third predetermined capacity. The third predetermined capacity is a preset value. For example, the third predetermined capacity is 50% of the storage capacity when fully charged.
[0059] When the start switch 130 is OFF, the detection unit 61 determines whether the charging state of the second power supply 20 is the fifth charging state. The fifth charging state is a state in which the storage capacity of the LiB 21 is less than the third predetermined capacity and greater than or equal to the fourth predetermined capacity. The fourth predetermined capacity is a preset value and is smaller than the third predetermined capacity. For example, the fourth predetermined capacity is 20% of the fully charged storage capacity.
[0060] When the start switch 130 is OFF, the detection unit 61 determines whether the charging state of the second power supply 20 is the sixth charging state. The sixth charging state is a state in which the energy storage capacity of the LiB 21 is less than the fourth predetermined capacity.
[0061] The switch setting unit 62 sets each of the switches 40 to 48 to ON or OFF and switches them accordingly. When the switch setting unit 62 is not in a predetermined backup state and is supplying power from the first power supply 10 to the first load group 100 and the second load group 110, it turns ON the first battery switch 40, the inter-system switch 43, and the first load switches 44 to the fifth load switches 48. In other words, when the vehicle is in a normal driving state, the switch setting unit 62 turns ON the first battery switch 40, the inter-system switch 43, and the first load switches 44 to the fifth load switches 48. As a result, as shown in Figure 2, power is supplied from the first power supply 10 to each load 101 to 103 of the first load group 100 via the first system 200. Figure 2 is a diagram showing the power supply by the first power supply 10. Power is also supplied from the first power supply 10 to each load 111 and 112 of the second load group 110 via the first system 200 and the second system 210. Specifically, power is supplied from the first power supply 10 to each load 111 and 112 of the second load group 110 via the first line 201, the connecting line 220, and the second line 211.
[0062] Furthermore, when the second power supply 20 is being charged, the switch setting unit 62 also turns on the second battery switch 41 and turns off the backup switch 42. The control unit 60 also drives the DC / DC 30. As a result, power is supplied from the first power supply 10 to the LiB 21 of the second power supply 20, and the LiB 21 is charged. When the LiB 21 is being charged, the backup switch 42 is turned off, and current flows through the DC / DC 30 to the LiB 21. When the LiB 21 of the second power supply 20 is not being charged, the switch setting unit 62 turns off the second battery switch 41.
[0063] If a ground fault occurs in the first system 200 during automatic operation and the second power supply 20 is in the first charging state, the switch setting unit 62 controls switches 40 to 48 so that power is supplied to all loads for automatic operation from the second power supply 20 via the second system 210. The switch setting unit 62 controls switches 40 to 48 so that power is supplied to the fourth load 111 and the fifth load 112 from the second power supply 20 via the second system 210. Specifically, the switch setting unit 62 turns OFF the first battery switch 40 and the inter-system switch 43. Furthermore, the switch setting unit 62 turns ON the second battery switch 41, the backup switch 42, the fourth load switch 47, and the fifth load switch 48. As a result, as shown in Figure 3, power is not supplied from the first power supply 10 to the first load group 100 and the second load group 110. Furthermore, power is supplied to the fourth load 111 and the fifth load 112 from the second power supply 20 via the second system 210. Figure 3 shows the power supply when a ground fault occurs in the first system 200 and the second power supply 20 is in the first charging state.
[0064] The switch setting unit 62 controls and turns on the load switches, namely the fourth load switch 47 and the fifth load switch 48, when a ground fault occurs in the first system 200 and the second power supply 20 is in the first charging state. As a result, power is supplied from the second power supply 20 to all backup loads included in the second load group 110, namely the fourth load 111 and the fifth load 112.
[0065] When the backup switch 42 is turned ON, current does not flow to the DC / DC 30, but flows to the backup switch 42, and then to the fourth load 111 and the fifth load 112.
[0066] If a ground fault occurs in the first system 200 during automatic operation and the second power supply 20 is in the second charging state, the switch setting unit 62 controls switches 40 to 48 so that power is supplied to the fourth load 111 from the second power supply 20 via the second system 210. In other words, the switch setting unit 62 controls switches 40 to 48 so that power is supplied to the fourth load 111, which has the highest priority among the loads for automatic operation. Specifically, the switch setting unit 62 turns OFF the first battery switch 40, the inter-system switch 43, and the fifth load switch 48. Furthermore, the switch setting unit 62 turns ON the second battery switch 41, the backup switch 42, and the fourth load switch 47. As a result, as shown in Figure 4, power is not supplied from the first power supply 10 to the first load group 100 and the second load group 110. Power is also supplied to the fourth load 111 from the second power supply 20 via the second system 210. Figure 4 shows the power supply when a ground fault occurs in the first system 200 and the second power supply 20 is in the second charging state.
[0067] If a ground fault occurs in the first system 200 and the second power supply 20 is in the second charging state, the switch setting unit 62 controls the fourth load switch 47, which is a load switch, and turns it ON. The switch setting unit 62 also controls the fifth load switch 48, which is a load switch, and turns it OFF. As a result, power is supplied from the second power supply 20 to the fourth load 111, which has the highest priority among the backup loads included in the second load group 110.
[0068] During manual operation, if the charging state of the second power supply 20 is the third charging state, the detection unit 61 prohibits automatic operation, and the switch setting unit 62 performs the same switch control as in the normal driving state shown in Figure 2.
[0069] As shown in Figure 5, the power control device 1 determines whether or not to enable automatic operation during manual operation according to the charge status of the second power supply 20, and switches to the execution of fail-safe control of automatic operation control using the second load group 110 if a ground fault occurs in the first system 200 during automatic operation. Figure 5 is a diagram showing the relationship between the charge status of the second power supply 20, whether or not to enable automatic operation control, and fail-safe control.
[0070] If automatic operation is permitted and a ground fault occurs in the first system 200 during automatic operation, and the charge state of the second power supply 20 is the same as the first charge state, the fail-safe control of the automatic operation control is executed. In this case, the fourth load switch 47 and the fifth load switch 48 are ON, and power is supplied from the second power supply 20 to all loads for automatic operation, namely the fourth load 111 and the fifth load 112.
[0071] If automatic operation is permitted and a ground fault occurs in the first system 200 during automatic operation, and the charge state of the second power supply 20 is the second charge state, the fail-safe control of the automatic operation control is executed. In this case, the fourth load switch 47 is ON and the fifth load switch 48 is OFF, and power is supplied from the second power supply 20 to the fourth load 111, which has a higher priority among the loads for automatic operation, while power is not supplied to the fifth load 112, which has a lower priority.
[0072] Automatic operation is not permitted if the charging state of the second power supply 20 is the third charging state.
[0073] Furthermore, when a ground fault occurs in the first system 200, there are two possible methods for controlling switches 40 to 48:
[0074] In the first control method, the switch setting unit 62 determines which load switches to turn ON according to the charge state of the second power supply 20 at the time a ground fault occurs in the first system 200, and maintains the ON / OFF state of each switch 40 to 48 until the fail-safe control is completed. As a result, the automatic operation control device 120 can perform appropriate fail-safe control according to the charge state of the second power supply 20 at the time of the ground fault until the fail-safe control is completed.
[0075] In the second control method, the switch setting unit 62 determines which load switches to turn ON according to the charge state of the second power supply 20 at the time a ground fault occurs in the first system 200, and continues to determine which load switches to turn ON according to the charge state of the second power supply 20 while fail-safe control is being performed. Specifically, when the charge state of the second power supply 20 is the first charge state at the time a ground fault occurs in the first system 200, the fourth load switch 47 and the fifth load switch 48 are turned ON to perform fail-safe control. If the charge state of the second power supply 20 drops to the second charge state during fail-safe control, the switch setting unit 62 turns OFF the fifth load switch 48 and performs fail-safe control only with the higher priority fourth load 111. Thereafter, even if the charge state of the second power supply 20 drops to the third charge state, fail-safe control continues only with the fourth load 111. Furthermore, if the second power supply 20 is in the second charging state at the time a ground fault occurs in the first system 200, the switch setting unit 62 turns on the fourth load switch 47 to perform fail-safe control only on the higher-priority fourth load 111. This allows fail-safe control to be performed for a longer period of time on the higher-priority load.
[0076] The above describes the control of the switch setting unit 62 while the vehicle is in motion with the start switch 130 in the ON position. However, the following control is performed when the vehicle is parked with the start switch 130 in the OFF position.
[0077] When the start switch 130 is turned OFF and the second power supply 20 is in the fourth charging state, the switch setting unit 62 controls switches 40 to 48 so that power is supplied from the second power supply 20 to all loads that operate while the start switch 130 is OFF. Specifically, the switch setting unit 62 controls switches 40 to 48 so that power is supplied from the second power supply 20 to the second load 102 and the third load 103. Specifically, the switch setting unit 62 turns OFF the first battery switch 40, the first load switch 44, the fourth load switch 47, and the fifth load switch 48. Furthermore, the switch setting unit 62 turns ON the second battery switch 41, the backup switch 42, the inter-system switch 43, the second load switch 45, and the third load switch 46. As a result, as shown in Figure 6, no power is supplied from the first power supply 10 to the first load group 100 and the second load group 110. Furthermore, power is supplied from the second power supply 20 to the second load 102 and the third load 103 of the first load group 100. Figure 6 shows the power supply when the start switch 130 is OFF and the charge state of the second power supply 20 is the fourth charge state.
[0078] The switch setting unit 62 controls the load switches, the second load switch 45 and the third load switch 46, to turn them ON when the start switch 130 is OFF and the second power supply 20 is in the fourth charging state. As a result, power is supplied from the second power supply 20 to both the standby loads, the second load 102 and the third load 103.
[0079] When the start switch 130 is OFF and the second power supply 20 is in the fifth charging state, the switch setting unit 62 controls switches 40 to 48 so that power is supplied to the second load 102 from the second power supply 20. In other words, the switch setting unit 62 controls switches 40 to 48 so that power is supplied to the second load 102, which has the highest priority among the loads that operate while the start switch 130 is OFF, from the second power supply 20. Specifically, the switch setting unit 62 turns OFF the first battery switch 40, the first load switch 44, the third load switch 46, the fourth load switch 47, and the fifth load switch 48. Furthermore, the switch setting unit 62 turns ON the second battery switch 41, the backup switch 42, the inter-system switch 43, and the second load switch 45. As a result, as shown in Figure 7, no power is supplied from the first power supply 10 to the first load group 100 and the second load group 110. Furthermore, power is supplied from the second power supply 20 to the second load 102 of the first load group 100. However, no power is supplied to the third load 103. Figure 7 shows the power supply when the start switch 130 is OFF and the charge state of the second power supply 20 is the fifth charge state.
[0080] The switch setting unit 62 controls the load switch, the second load switch 45, to turn it ON when the start switch 130 is OFF and the second power supply 20 is in the fifth charging state. The switch setting unit 62 also controls the third load switch 46 to turn it OFF. As a result, power is supplied from the second power supply 20 to the second load 102, which has a higher priority among the standby loads.
[0081] When the start switch 130 is OFF and the charging state of the second power supply 20 is the sixth charging state, the switch setting unit 62 turns all switches 40 to 48 OFF, as shown in Figure 8. Figure 8 shows the state of each switch 40 to 48 when the start switch 130 is OFF and the charging state of the second power supply 20 is the sixth charging state.
[0082] When the start switch 130 is OFF, the power control device 1 switches the power supply to the second load 102 and the third load 103 of the first load group 100 according to the charge state of the second power supply 20, as shown in Figure 9. Figure 9 is a diagram showing the relationship between the charge state of the second power supply 20 and the power supply when the start switch 130 is OFF.
[0083] When the start switch 130 is OFF and the charging state of the second power supply 20 is the fourth charging state, power is supplied from the second power supply 20 to all standby loads, namely the second load 102 and the third load 103.
[0084] If the start switch 130 is OFF and the charging state of the second power supply 20 is the fifth charging state, power is supplied from the second power supply 20 to the second load 102, which has the highest priority among the standby loads. Power is not supplied from the second power supply 20 to the third load 103, which has the lowest priority.
[0085] If the start switch 130 is OFF and the charging state of the second power supply 20 is the sixth charging state, power supply to all loads 101-103, 111, and 112 is stopped.
[0086] Furthermore, if the start switch 130 is OFF and the charge state of the second power supply 20 is the sixth charge state, power may be supplied from the first power supply 10 to the second load 102 and the third load 103. In this case, the second load switch 45 and the third load switch 46 may be turned ON or OFF depending on the storage capacity of the PbB 12 of the first power supply 10.
[0087] When the start switch 130 is OFF, there are two possible control methods for switches 40 to 48, similar to the control methods for switches 40 to 48 when a ground fault occurs in the first system 200.
[0088] In the first control method, the switch setting unit 62 determines which load switches to turn ON according to the charge state of the second power supply 20 at the time the start switch 130 is turned OFF, and then maintains the ON and OFF states of each switch 40 to 48.
[0089] In the second control method, the switch setting unit 62 determines which load switches to turn ON based on the charge state of the second power supply 20 at the time the start switch 130 is turned OFF. Specifically, if the charge state of the second power supply 20 at the time the start switch 130 is turned OFF is the fourth charge state, the switch setting unit 62 turns ON the second load switch 45 and the third load switch 46. Subsequently, when the charge state of the second power supply 20 drops to the fifth charge state, the switch setting unit 62 turns ON the second load switch 45 and OFF the third load switch 46 to supply power only to the second load 102, which has a higher priority. Furthermore, when the charge state of the second power supply 20 drops to the sixth charge state, the switch setting unit 62 turns OFF all switches 40 to 48.
[0090] Next, the fail-safe process according to the embodiment will be explained with reference to Figure 10. Figure 10 is a flowchart illustrating the fail-safe process when a ground fault occurs in the first system 200.
[0091] The power control device 1 detects the charge state of the second power supply 20 (S100). The power control device 1 determines whether the charge state of the second power supply 20 is the first charge state or the second charge state (S101).
[0092] Specifically, the power control device 1 determines whether the storage capacity of LiB21 is equal to or greater than a first predetermined capacity. If the storage capacity of LiB21 is equal to or greater than the first predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the first charge state. If the storage capacity of LiB21 is less than the first predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is not the first charge state.
[0093] Furthermore, the power control device 1 determines whether the storage capacity of LiB21 is less than a first predetermined capacity and greater than or equal to a second predetermined capacity. If the storage capacity of LiB21 is less than a first predetermined capacity and greater than or equal to a second predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the second charge state. If the storage capacity of LiB21 is less than a second predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is not the second charge state. In other words, if the storage capacity of LiB21 is less than a second predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the third charge state.
[0094] The power control device 1 permits automatic operation (S102) if the charge state of the second power supply 20 is the first charge state or the second charge state (S101: Yes). The power control device 1 prohibits automatic operation (S103) if the charge state of the second power supply 20 is neither the first charge state nor the second charge state (S101: No), i.e., if the second power supply 20 is in the third charge state.
[0095] The power control device 1 determines whether the vehicle is in automatic driving mode (S104). If the power control device 1 determines that the vehicle is not in automatic driving mode (S104: No), it terminates the current process. If the charging state of the second power supply 20 is the third charging state, automatic driving is prohibited and therefore not started. In this case, the process terminates without proceeding to step S105.
[0096] If the power control device 1 is in automatic operation mode (S104: Yes), it determines whether or not a ground fault has occurred in the first system 200 (S105). Specifically, the power control device 1 determines whether or not the voltage detected by the first voltage sensor 50 is within the normal range. If the voltage detected by the first voltage sensor 50 is within the normal range, the power control device 1 determines that no ground fault has occurred in the first system 200. If the voltage detected by the first voltage sensor 50 is not within the normal range, the power control device 1 determines that a ground fault has occurred in the first system 200.
[0097] The power control device 1 terminates the current process if no ground fault has occurred in the first system 200 (S105: No).
[0098] If a ground fault occurs in the first system 200 (S105: Yes), the power control device 1 determines whether the charge state of the second power supply 20 is the first charge state (S106).
[0099] If the second power supply 20 is in the first charging state (S106: Yes), the power control device 1 supplies power from the second power supply 20 to the fourth load 111 and the fifth load 112 (S107). In other words, the power control device 1 causes the fourth load 111 and the fifth load 112 to perform fail-safe control of the automatic operation control. Specifically, the power control device 1 turns ON the second battery switch 41, the backup switch 42, the fourth load switch 47, and the fifth load switch 48, and turns OFF the first battery switch 40 and the inter-system switch 43.
[0100] If the charge state of the second power supply 20 is not the first charge state (S106: No), the power supply control device 1 determines whether the charge state of the second power supply 20 is the second charge state (S108).
[0101] If the second power supply 20 is in the second charging state (S108: Yes), the power control device 1 supplies power from the second power supply 20 to the fourth load 111 (S109). In other words, the power control device 1 causes the fourth load 111 to perform fail-safe control. Specifically, the power control device 1 turns on the second battery switch 41, the backup switch 42, and the fourth load switch 47, and turns off the first battery switch 40, the inter-system switch 43, and the fifth load switch 48.
[0102] The power control device 1 terminates the current process if the charge state of the second power supply 20 is not the second charge state (S108: No), that is, if the charge state of the second power supply 20 is the third charge state.
[0103] Furthermore, if a ground fault occurs during automatic operation and the charge state of the second power supply 20 is the first charge state or the second charge state, and subsequently the charge state of the second power supply 20 becomes the third charge state, automatic operation is prohibited (S103). However, since automatic operation is already being performed, it is determined in step S104 that automatic operation is in progress (104: Yes). Then, the fail-safe control by the fourth load 111, which was set in step S109 in the previous process, is continued.
[0104] Furthermore, the power control device 1 switches the fifth load switch 48 from ON to OFF when a ground fault occurs in the first system 200 and the charge state of the second power supply 20 changes from the first charge state to the second charge state. In other words, when a ground fault occurs in the first system 200 and power is supplied from the second power supply 20 to the fourth load 111 and the fifth load 112, the charge state of the second power supply 20 decreases and changes from the first charge state to the second charge state, the fifth load switch 48 turns OFF.
[0105] Next, the standby process according to the embodiment will be explained with reference to Figure 11. Figure 11 is a flowchart illustrating the standby process when the start switch 130 is OFF.
[0106] The power control device 1 determines whether the start switch 130 is OFF or not (S200). If the start switch 130 is not OFF (S200: No), the power control device 1 terminates the current process.
[0107] If the start switch 130 is OFF (S200: Yes), the power control device 1 detects the charging status of the second power supply 20 (S201).
[0108] The power control device 1 determines whether the charge state of the second power supply 20 is the fourth charge state (S202). Specifically, the power control device 1 determines whether the storage capacity of the LiB 21 is equal to or greater than the third predetermined capacity. If the storage capacity of the LiB 21 is equal to or greater than the third predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the fourth charge state. If the storage capacity of the LiB 21 is less than the third predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is not the fourth charge state.
[0109] If the second power supply 20 is in the fourth charging state (S202: Yes), the power control device 1 supplies power from the second power supply 20 to all standby loads, namely the second load 102 and the third load 103 (S203). Specifically, the power control device 1 turns on the second battery switch 41, the backup switch 42, the inter-system switch 43, the second load switch 45, and the third load switch 46. The power control device 1 also turns off the first battery switch 40, the first load switch 44, the fourth load switch 47, and the fifth load switch 48.
[0110] If the charge state of the second power supply 20 is not the fourth charge state (S202: No), the power control device 1 determines whether the charge state of the second power supply 20 is the fifth charge state (S204). Specifically, the power control device 1 determines whether the storage capacity of the LiB 21 is less than the third predetermined capacity and greater than or equal to the fourth predetermined capacity. If the storage capacity of the LiB 21 is less than the third predetermined capacity and greater than or equal to the fourth predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the fifth charge state. If the storage capacity of the LiB 21 is less than the fourth predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is not the fifth charge state. In other words, if the storage capacity of the LiB 21 is less than the fourth predetermined capacity, the power control device 1 determines that the charge state of the second power supply 20 is the sixth charge state.
[0111] If the second power supply 20 is in the fifth charging state (S204: Yes), the power control device 1 supplies power from the second power supply 20 to the second load 102, which has the highest priority among the standby loads (S205). Specifically, the power control device 1 turns on the second battery switch 41, the backup switch 42, the inter-system switch 43, and the second load switch 45. The power control device 1 also turns off the first battery switch 40, the first load switch 44, the third load switch 46, the fourth load switch 47, and the fifth load switch 48.
[0112] If the second power supply 20 is not in the fifth charging state (S204: No), that is, if the second power supply 20 is in the sixth charging state, the power control device 1 stops supplying power from the second power supply 20 to all loads 101-103, 111, and 112 (S206). Specifically, the power control device 1 turns off each of the switches 40-48. The power control device 1 may also turn off the first battery switch 40 and the second battery switch 41, and turn on at least one of the other switches 42-48.
[0113] Furthermore, the power control device 1 switches the third load switch 46 from ON to OFF when the start switch 130 is OFF and the charge state of the second power supply 20 changes from the fourth charge state to the fifth charge state. When the start switch 130 is OFF and power is supplied from the second power supply 20 to the second load 102 and the third load 103, the charge state of the second power supply 20 decreases and changes from the fourth charge state to the fifth charge state, the third load switch 46 is turned OFF.
[0114] Furthermore, if the start switch 130 is OFF and the charging state of the second power supply 20 changes from the fifth charging state to the sixth charging state, the power control device 1 may supply power to the second load 102 from the first power supply 10 instead of the second power supply 20. In this case, the switch for the first battery 40 is turned ON, and the switch for the second battery 41 and the inter-system switch 43 are turned OFF.
[0115] The power control device 1 comprises a first system 200, a second system 210, a plurality of switches (load switches) 44 to 48, and a control unit 60. The first system 200 can supply power from the first power supply 10 to the first load group 100. The second system 210 can supply power from the second power supply 20 to the second load group 110. The plurality of switches 44 to 48 can switch the power supply to each load 101 to 103, 111, and 112 of the first load group 100 and the second load group 110, respectively. The control unit 60 controls the plurality of switches 44 to 48 so that power is supplied from the second power supply 20 to the loads (backup loads) 101 to 103, 111, and 112 included in at least one of the first load group 100 and the second load group 110 in a predetermined backup state. The control unit 60 detects the charge state of the second power supply 20, and in a predetermined backup state, increases the number of switches 44-48 connected as the charge state increases.
[0116] As a result, the power control device 1 can supply power from the second power supply 20 to loads 101-103, 111, and 112 according to the charge state of the second power supply 20. Therefore, the power control device 1 can extend the operating time of loads 101-103, 111, and 112. For example, when the charge state of the second power supply 20 is low, the power control device 1 reduces the number of loads 101-103, 111, and 112 supplied from the second power supply 20 in a predetermined backup state. Therefore, the power control device 1 can extend the operating time of loads 101-103, 111, and 112 with the power supplied from the second power supply 20.
[0117] The specified backup state includes a state in which a ground fault occurs in the first system 200.
[0118] As a result, when a ground fault occurs in the first system 200, the power control device 1 can change the number of loads 111 and 112 that are powered and operated by the second power supply 20, depending on the charge state of the second power supply 20. Therefore, when a ground fault occurs in the first system 200 and the charge state of the second power supply 20 is high, the power control device 1 can operate many loads 111 and 112 to perform fail-safe control of automatic operation control. Also, when a ground fault occurs in the first system 200 and the charge state of the second power supply 20 is low, the power control device 1 can reduce the number of loads to be operated and increase the operating time of the loads 112.
[0119] The power control device 1 includes an inter-system switch 43. The inter-system switch 43 connects or disconnects the first system 200 and the second system 210. When a ground fault occurs in the first system 200, the control unit 60 disconnects the first system 200 and the second system 210 using the inter-system switch 43. When the charge state of the second power supply 20 is the first charge state, the control unit 60 controls the fourth load switch 47 and the fifth load switch 48 when a ground fault occurs in the first system 200. The control unit 60 controls the fourth load switch 47 and the fifth load switch 48 so that power is supplied to the fourth load 111 and the fifth load 112 from the second system 210. When the charge state of the second power supply 20 is the second charge state, which is lower than the first charge state, the control unit 60 controls the fourth load switch 47 and the fifth load switch 48 when a ground fault occurs in the first system 200. The control unit 60 controls the fourth load switch 47 and the fifth load switch 48 so that power is supplied from the second power supply 20 to the fourth load 111, which has a higher priority.
[0120] As a result, if the second power supply 20 is in the first charging state and a ground fault occurs in the first system 200, the power control device 1 can supply power from the second power supply 20 to the fourth load 111 and the fifth load 112. Therefore, the power control device 1 can operate the fourth load 111 and the fifth load 112 to execute the fail-safe control of the automatic operation control. Furthermore, if the second power supply 20 is in the second charging state and a ground fault occurs in the first system 200, the power control device 1 will supply power from the second power supply 20 only to the fourth load 111, which has a higher priority. As a result, if the second power supply 20 is in the second charging state and a ground fault occurs in the first system 200, the power control device 1 can extend the operating time of the fourth load 111. Therefore, the power control device 1 can reliably execute the fail-safe control of the automatic operation control. The power control device 1 can move the vehicle to a safe location by fail-safe control of the automatic driving control when a ground fault occurs in the first system 200.
[0121] When a ground fault occurs in the first system 200, and the charge state of the second power supply 20 changes from the first charge state to the second charge state, the control unit 60 shuts off the fifth load switch 48 that supplies power to the fifth load 112, which has a lower priority.
[0122] As a result, the power control device 1 can prevent the power supply time from the second power supply 20 to the fourth load 111 from becoming shorter when the charge state of the second power supply 20 becomes low. Therefore, the power control device 1 can extend the operating time of the fourth load 111.
[0123] The control unit 60 allows control by the fourth load 111, or by the fourth load 111 and the fifth load 112, if the charge state of the second power supply 20 is the first charge state or the second charge state. The control unit 60 prohibits control by the fourth load 111 and the fifth load 112 if the charge state of the second power supply 20 is the third charge state, which is lower than the second charge state.
[0124] As a result, the power control device 1 can prevent the fail-safe control of the automatic operation control from starting when the charging state of the second power supply 20 is in the third charging state.
[0125] The specified backup state includes the state in which the power system's start switch 130 is OFF.
[0126] As a result, when the start switch 130 is OFF, the power control device 1 can change the number of loads 102 and 103 that are powered and operated by the second power supply 20, depending on the charge state of the second power supply 20. Therefore, when the start switch 130 is OFF and the charge state of the second power supply 20 is high, the power control device 1 can suppress the decrease in the storage capacity of the first power supply 10 and operate the second load 102 and the third load 103 by power supply from the second power supply 20. Also, when the start switch 130 is OFF and the charge state of the second power supply 20 is low, the power control device 1 can suppress the decrease in the storage capacity of the second power supply 20 by operating only the second load 102. In other words, the power control device 1 can extend the operating time of the second load 102 powered by the power supply from the second power supply 20.
[0127] When the start switch 130 is OFF, the control unit 60 controls the second load switch 45 and the third load switch 46 if the charge state of the second power supply 20 is the fourth charge state. The control unit 60 controls the second load switch 45 and the third load switch 46 so that power is supplied from the second system 210 to the second load 102 and the third load 103 (all standby loads). When the start switch 130 is OFF, the control unit 60 controls the second load switch 45 and the third load switch 46 if the charge state of the second power supply 20 is the fifth charge state, which is lower than the fourth charge state. The control unit 60 controls the second load switch 45 and the third load switch 46 so that power is supplied from the second power supply 20 to the second load 102, which has a higher priority than the second load 103.
[0128] As a result, when the start switch 130 is OFF and the charge state of the second power supply 20 is low, the power control device 1 can operate the second load 102 and the third load 103 by power supply from the second power supply 20. Therefore, the power control device 1 can suppress the decrease in the storage capacity of the first power supply 10. In addition, when the start switch 130 is OFF and the charge state of the second power supply 20 is low, the power control device 1 can suppress the decrease in the storage capacity of the second power supply 20 by operating only the second load 102, which has a higher priority. In other words, the power control device 1 can extend the operating time of the second load 102 by power supply from the second power supply 20.
[0129] When the start switch 130 is OFF, the control unit 60 shuts off the third load switch 46 that supplies power to the third load 103 if the charge state of the second power supply 20 changes from the fourth charge state to the fifth charge state. The control unit 60 shuts off the third load switch 46 that supplies power to the third load 103, which has the lower priority among the second load 102 and the third load 103.
[0130] As a result, the power control device 1 can stop supplying power to the third load 103, which has a lower priority, when the start switch 130 is OFF and the charge state of the second power supply 20 becomes low. Therefore, the power control device 1 can extend the operating time of the second load 102 powered by the second power supply 20.
[0131] When the start switch 130 is OFF, the control unit 60 will not supply power to the second load 102 and the third load 103 if the charge state of the second power supply 20 is a sixth charge state, which is lower than the fifth charge state.
[0132] As a result, the power control device 1 can suppress voltage drops in the second power supply 20 and the first power supply 10. Therefore, the power control device 1 can shorten the time during which backup control cannot be performed after the start switch 130 is turned ON until the LiB 21 of the second power supply 20 is charged.
[0133] When the start switch 130 is OFF, the control unit 60 controls the second load switch 45 and the third load switch 46 if the charge state of the second power supply 20 is a sixth charge state, which is lower than the fifth charge state. The control unit 60 controls the second load switch 45 and the third load switch 46 so that power is supplied from the first power supply 10 to the second load 102, which has a higher priority than the second load 102 and the third load 103.
[0134] As a result, the power control device 1 can continue the operation of the second load 102 even when the start switch 130 is OFF and the charge state of the second power supply 20 has decreased.
[0135] The power control device 1 may be capable of performing either the fail-safe process described above or the standby process described above.
[0136] At least one of the first loads 101 to the fifth loads 112 may be further divided into multiple loads. In this case, a switch for switching the power supply to each load is provided according to each load. Each load is also assigned a priority, and in the fail-safe process or standby process described above, each switch is controlled based on the charge state of the second power supply 20 and its priority.
[0137] Furthermore, one of the recognition system loads, such as the in-vehicle camera and radar, may be designated as the fourth load 111, and the remaining loads as the fifth load 112. This allows fail-safe control to be performed using the recognition system loads included in the fourth load 111 when the charge state of the second power supply 20 is the second charge state. In other words, even when the charge state of the second power supply 20 is low, the vehicle can be reliably moved to a safe location by fail-safe control.
[0138] Further effects and modifications can be readily derived by those skilled in the art. Therefore, broader aspects of the present invention are not limited to the specific details and representative embodiments expressed and described above. Accordingly, various modifications are possible without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents. [Explanation of symbols]
[0139] 1 Power supply control device 10 1st power supply 20 2nd power supply 43 Inter-system switches 44. First load switch 45. Second load switch 46. Third load switch 47. Fourth load switch 48. Fifth load switch 60 Control Unit 61 Detection unit 62 Switch setting section 100 1st load group 101 1st load 102 Second load (backup load, standby load) 103 Third load (backup load, standby load) 110 2nd load group 111 Fourth load (backup load) 112 Fifth load (backup load) 130 Start switch 200 1st system 210 2nd system 220 connection lines
Claims
1. A first system capable of supplying power from the first power source to the first load group, A second system capable of supplying power from the second power source to the second load group, Multiple load switches capable of switching the power supply to each load in the second load group, A system-to-system switch for connecting or disconnecting the first system and the second system, In a backup state where a ground fault occurs in the first system, a control unit shuts off the inter-system switch and controls the plurality of load switches so that power is supplied from the second power supply to the second load group. Equipped with, The control unit, The charging state of the second power supply is detected, In the backup state, if the charging state is the first charging state, when the ground fault occurs, the plurality of load switches are controlled so that power is supplied from the second power supply to all backup loads included in the second load group, thereby allowing control by the backup loads. If the charging state is a second charging state which is lower than the first charging state, then in the state in which the ground fault occurs, the multiple load switches are controlled so that power is supplied from the second power supply to the backup load with the higher priority among the backup loads included in the second load group, thereby allowing control by the backup load. A power control device that prohibits control by a backup load when the aforementioned charging state is a third charging state that is lower than the second charging state.
2. A first system capable of supplying power from the first power source to the first load group, A second power supply system capable of supplying power from the second power source to a second load group, including loads used during the vehicle's automated operation, Multiple load switches capable of switching the power supply to each load in the second load group, A system-to-system switch for connecting or disconnecting the first system and the second system, In a backup state where a ground fault occurs in the first system, a control unit shuts off the inter-system switch and controls the plurality of load switches so that power is supplied from the second power supply to the second load group. Equipped with, The control unit, The charging state of the second power supply is detected, In the backup state, if the charging state is the first charging state, when the ground fault occurs, the plurality of load switches are controlled so that power is supplied from the second power source to all backup loads included in the second load group, thereby permitting the automatic operation. If the charging state is a second charging state which is lower than the first charging state, the multiple load switches are controlled so that power is supplied from the second power supply to the backup load with the higher priority among the backup loads included in the second load group when the ground fault occurs, and the automatic operation is permitted. A power control device that prohibits automatic operation if the charging state is a third charging state that is lower than the second charging state.
3. A first system capable of supplying power from the first power source to the first load group, A second system capable of supplying power from the second power source to the second load group, Multiple load switches capable of switching the power supply to each load in the first load group and the second load group, respectively, A control unit controls the plurality of load switches so that power is supplied from the second power supply to backup loads included in at least one of the first load group and the second load group in a predetermined backup state, including a state in which the start switch of the power supply system is OFF. Equipped with, The control unit, The charging state of the second power supply is detected, A power control device that, in the predetermined backup state, increases the number of connected load switches as the charge level increases.
4. The control unit, When the start switch is OFF and the charging state is the fourth charging state, the plurality of load switches are controlled so that power is supplied from the second power supply to all of the standby loads among the backup loads. The power control device according to claim 3, wherein, when the start switch is OFF, the charging state is a fifth charging state which is lower than the fourth charging state, the plurality of load switches are controlled so that power is supplied from the second power supply to the standby load with the higher priority among the standby loads.
5. The control unit, The power control device according to claim 4, wherein, when the start switch is OFF, the charging state changes from the fourth charging state to the fifth charging state, the load switch that supplies power to the low-priority standby load is shut off.
6. The control unit, The power supply control device according to claim 4 or 5, wherein, when the start switch is OFF, the charging state is a sixth charging state lower than the fifth charging state, power is not supplied to the standby load.
7. The control unit, The power control device according to claim 4 or 5, wherein, when the start switch is OFF, the charging state is a sixth charging state which is lower than the fifth charging state, the plurality of load switches are controlled so that power is supplied from the first power supply to the standby load with the higher priority among the standby loads.
8. A control method in which a control unit controls a power control device having a first system capable of supplying power from a first power source to a first load group, a second system capable of supplying power from a second power source to a second load group, a plurality of load switches capable of switching the power supply to each load of the second load group, and an inter-system switch for connecting or disconnecting the first system and the second system, In the backup state where a ground fault occurs in the first system, the inter-system switch is shut off, and the plurality of load switches are controlled so that power is supplied from the second power source to the second load group. In the backup state, if the detected charge state of the second power supply is the first charge state, the plurality of load switches are controlled so that power is supplied from the second power supply to all backup loads included in the second load group in the state in which the ground fault occurs, thereby allowing control by the backup loads. If the charging state is a second charging state which is lower than the first charging state, then in the state in which the ground fault occurs, the multiple load switches are controlled so that power is supplied from the second power supply to the backup load with the higher priority among the backup loads included in the second load group, thereby allowing control by the backup load. A control method that prohibits control by a backup load when the aforementioned charge state is a third charge state that is lower than the second charge state.
9. A control method in which a control unit controls a power control device having a first system capable of supplying power from a first power source to a first load group, a second system capable of supplying power from a second power source to a second load group including loads used during automatic operation of a vehicle, a plurality of load switches capable of switching the power supply to each load in the second load group, and an inter-system switch for connecting or disconnecting the first system and the second system, In the backup state where a ground fault occurs in the first system, the inter-system switch is shut off, and the plurality of load switches are controlled so that power is supplied from the second power source to the second load group. In the backup state, if the detected charge state of the second power supply is the first charge state, the multiple load switches are controlled so that power is supplied from the second power supply to all backup loads included in the second load group when the ground fault occurs, thereby permitting the automatic operation. If the charging state is a second charging state which is lower than the first charging state, the multiple load switches are controlled so that power is supplied from the second power supply to the backup load with the higher priority among the backup loads included in the second load group when the ground fault occurs, and the automatic operation is permitted. A control method that prohibits automatic operation if the charging state is a third charging state that is lower than the second charging state.
10. A control method in which a control unit controls a power supply control device having a first system capable of supplying power from a first power source to a first load group, a second system capable of supplying power from a second power source to a second load group, and a plurality of load switches capable of switching the power supply to each load in the first load group and the second load group, respectively, In a predetermined backup state, including the state in which the start switch of the power supply system is OFF, the plurality of load switches are controlled so that power is supplied from the second power supply to the backup loads included in at least one of the first load group and the second load group. A control method in which, in the predetermined backup state, the number of connected load switches is increased as the detected charge state of the second power supply increases.