Power supply device and power supply control method

Abstract

To provide a power supply device and a power supply control method that suppress the occurrence of a time when power is not supplied to a load.SOLUTION: A power supply device according to an embodiment includes a first system, a second system, a connection line, a cutoff mechanism, a connection mechanism, a storage unit, and a supply unit. The connection line connects the first system that supplies power from a first battery to a first load and the second system that supplies power from a second battery to a second load. The cutoff mechanism is provided on the connection line and cuts off the first system and the second system when a failure occurs in the first system. The connection mechanism is provided in the second system, and connects the second battery and the second load so that power is supplied from the second battery to the second load in the event of a failure in the first system. The storage unit stores energy by the current flowing from the first battery. The supply unit is provided so that the electric power based on the energy stored in the storage unit is supplied to the second load when the first system and the second system are cut off.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a power supply device and a power supply control method. [Background technology]

[0002] Conventionally, a power supply device capable of supplying power from a main battery and a secondary battery to a backup load has been disclosed (see, for example, Patent Document 1). In the conventional power supply device, when a failure occurs in the power supply system on the main battery side, the first relay is turned OFF to separate the power supply system on the main battery side, and the second relay is turned ON to supply power from the secondary battery to the backup load via the power supply system on the secondary battery side. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-61240 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in a conventional power supply device, if a failure occurs in the power supply system on the main battery side while the second relay is in the OFF state, power is not supplied to the backup load until the second relay is turned ON. In other words, in a conventional power supply device, there is a risk of a period of time during which power supply to the backup load is cut off.

[0005] The present invention has been made in view of the above, and has an object to provide a power supply device and a power supply control method that prevent the power supply to a load from being cut off. [Means for solving the problem]

[0006] In order to solve the above-mentioned problems and achieve the object, a power supply device according to the present invention includes a first system, a second system, a connection line, a cutoff mechanism, a connection mechanism, a storage unit, and a supply unit. The first system supplies power from a first battery to a first load. The second system supplies power from a second battery to a second load. The connection line connects the first system and the second system. The cutoff mechanism is provided in the connection line and cuts off the first system and the second system when a failure occurs in the first system. The connection mechanism is provided in the second system and connects the second battery and the second load so that power is supplied from the second battery to the second load when a failure occurs in the first system. The storage unit is provided on a path opposite to the first system with respect to the cutoff mechanism and stores energy by a current flowing from the first battery. The supply unit is provided so that when the first system and the second system are cut off, power based on the energy stored in the storage unit is supplied to the second load. Effect of the Invention

[0007] According to the present invention, it is possible to prevent the power supply to the load from being cut off. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a power supply device according to an embodiment. [Diagram 2] FIG. 2 is a block diagram of the control device according to the embodiment. [Diagram 3] FIG. 3 is a diagram showing power supply in a normal state. [Figure 4A] FIG. 4A is a diagram (part 1) showing power supply when a power failure occurs in the first system. [Figure 4B] FIG. 4B is a diagram (part 2) showing power supply when a power failure occurs in the first system. [Diagram 5] FIG. 5 is a flowchart illustrating a control process when a power failure occurs in the first system or the second system according to the embodiment. [Figure 6] FIG. 6 is a diagram showing an example of the configuration of a power supply device according to a modified example. [Figure 7] FIG. 7 is a diagram showing an example of the configuration of a power supply device according to a modified example. [Figure 8] FIG. 8 is a diagram showing an example of the configuration of a power supply device according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of a power supply control device and a power supply control method disclosed in the present application will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments described below.

[0010] First, a configuration example of a power supply device 1 according to an embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing a configuration example of a power supply device according to an embodiment. The power supply device 1 according to the embodiment is a device mounted in a vehicle, and executes a power supply control method according to an embodiment. The vehicle is a vehicle equipped with a system that requires a backup power supply. Below, a vehicle equipped with an autonomous driving system, which is one example of such a system, will be described.

[0011] As shown in Fig. 1, a power supply device 1 according to an embodiment includes a power generation device 2, a main battery 3 (first battery), a backup battery 4 (second battery), a first load 5, a second load 6, a first system 7, a second system 8, a connection line 9, and a control device 10. In Fig. 1, lines through which power is supplied are indicated by solid lines, and lines through which control signals are transmitted are indicated by dashed lines. The first system 7, the second system 8, and the connection line 9 form a power supply circuit for supplying power to the first load 5 and the second load 6.

[0012] The power generation device 2 includes an alternator, a DC-DC converter, etc. The power generation device 2 may include a motor generator.

[0013] The main battery 3 is charged by being supplied with power from the power generation device 2. The main battery 3 is a battery that supplies power to the first load 5 and the second load 6 when there is no power supply failure in the first system 7. Note that here, the power supply failure indicates the occurrence of a ground fault in the system. The main battery 3 is, for example, a lead-acid battery. The main battery 3 is not limited to a lead-acid battery, and may be a lithium-ion battery or the like.

[0014] The backup battery 4 is a battery that supplies power to the second load 6 in the event of a power failure in the first system 7. The backup battery 4 is charged by receiving power from the main battery 3. The backup battery 4 is, for example, a lithium ion battery. Note that the backup battery 4 is not limited to a lithium ion battery, and may be a lead storage battery or the like.

[0015] The first load 5 and the second load 6 are loads for performing automatic driving. The first load 5 and the second load 6 include sensors and actuators for automatic driving. The first load 5 and the second load 6 include, for example, a millimeter wave radar for detecting obstacles, a LiDAR (Laser Imaging Detection and Ranging) for detecting obstacles, and a camera for detecting obstacles. In addition, the first load 5 and the second load 6 include, for example, a brake actuator for generating a braking force and a steering actuator (for example, EPS (Electric Power Steering)) for operating the steering.

[0016] In a normal state where no power failure occurs in the first system 7 and the second system 8, automatic operation is performed using the first load 5 and the second load 6.

[0017] Furthermore, in the event of a power failure in either the first system 7 or the second system 8, evacuation driving can be performed by the first load 5 or the second load 6. Evacuation driving includes driving in which part of the autonomous driving is performed. In other words, in the event of a power failure in either the first system 7 or the second system 8, the vehicle can run while restricting the autonomous driving function more than in normal times.

[0018] For example, the first load 5 includes a millimeter wave radar, a brake actuator, and a steering actuator, and the second load 6 includes a LiDAR, a camera, a brake actuator, and a steering actuator.

[0019] Even if a power failure occurs in either the first system 7 or the second system 8, the vehicle can perform evacuation driving using, for example, a millimeter wave radar, a brake actuator, or a steering actuator included in the first load 5, or a LiDAR, a camera, a brake actuator, or a steering actuator included in the second load 6.

[0020] The vehicle includes two brake actuators as a first load 5 and a second load 6. The vehicle generates a braking force by the two brake actuators in a normal state. When a power failure occurs in either the first system 7 or the second system 8, the vehicle generates a braking force by one brake actuator of the system in which the power failure does not occur. For example, the vehicle generates a braking force by one brake actuator similar to the braking force by the two brake actuators in a normal state. Note that the vehicle may, for example, limit the vehicle speed and generate a braking force by one brake actuator that is smaller than the braking force by the two brake actuators in a normal state.

[0021] The first system 7 is a first power supply line that connects the main battery 3 and the first load 5. The first system 7 supplies power from the main battery 3 to the first load 5. Note that a load other than the above-mentioned first load 5 and second load 6, for example, a load that is not used for evacuation driving, such as an audio device, is connected to the first system 7.

[0022] The second system 8 is a second power supply line that connects the backup battery 4 and the second load 6. The second system 8 supplies power from the backup battery 4 to the second load 6. The first system 7 and the second system 8 are electrically provided in parallel. Note that the second system 8 can also be a line that supplies power from the main battery 3 to the backup battery 4 and the second load 6 during normal operation.

[0023] Although detailed description will be omitted, a vehicle control device for controlling the entire vehicle including the first load 5 and the second load 6 is connected to the first system 7 and the second system 8. Therefore, even if a power failure occurs in either the first system 7 or the second system 8, power is supplied to the vehicle control device from either the main battery 3 or the backup battery 4. The vehicle control device may be provided integrally with the control device 10.

[0024] The second system 8 is provided with a charging mechanism 20 and a first switch 21. The charging mechanism 20 is provided between the connection line 9 and the backup battery 4. When charging the backup battery 4, the charging mechanism 20 adjusts the current and voltage to the backup battery 4. The charging mechanism 20 includes, for example, a DC-DC converter.

[0025] The first switch 21 is provided electrically in parallel with the charging mechanism 20. The first switch 21 is a connection mechanism that connects the second battery and the second load 6 so that power is supplied from the second battery to the second load 6 when a power failure occurs in the first system 7. When the backup battery 4 is being charged, the first switch 21 is in an open state, i.e., OFF. Therefore, charging of the backup battery 4 is performed via the charging mechanism 20. When power is supplied from the backup battery 4 to the second load 6, the first switch 21 is in a connected state, i.e., ON.

[0026] The connection line 9 connects the first system 7 and the second system 8. On the connection line 9, a second switch 30, a first detection unit 31, and a coil 32 are provided.

[0027] The second switch 30 is a cutoff mechanism that switches the electrical connection state between the first system 7 and the second system 8. The second switch 30 is in a connected state, i.e., ON, during normal operation when no power failure occurs in the first system 7 and the second system 8. The second switch 30 is in a cutoff state, i.e., OFF, when a power failure occurs in the first system 7 or the second system 8. When the second switch 30 is turned OFF, the first system 7 and the second system 8 are electrically cut off.

[0028] The first detection unit 31 is a sensor for detecting a power failure in the first system 7 or the second system 8. The first detection unit 31 is a current sensor for detecting a current flowing through the connection line 9. When a power failure occurs in the first system 7, no current flows through the connection line 9, and the current value I1 detected by the first detection unit 31 becomes equal to or less than a first predetermined value P1. The first predetermined value P1 is a preset value, and is approximately zero. In other words, the first predetermined value P1 is a value that can determine that a ground fault has occurred in the first system 7.

[0029] Furthermore, if a power failure occurs in the second system 8, the current flowing through the connection line 9 increases, and the current value I1 detected by the first detection unit 31 becomes equal to or greater than the second predetermined value P2. The second predetermined value P2 is a preset value and is greater than the first predetermined value P1. The second predetermined value P2 is a value greater than the value due to power consumption by the second load 6, and is a value at which it is possible to determine that a power failure has occurred in the second system 8. In other words, the second predetermined value P2 is a value at which it is possible to determine that an overcurrent has occurred in the second system 8 due to a ground fault.

[0030] In addition, FIG. 1 shows an example in which the first detection unit 31 is provided between the second switch 30 and the first system 7, but this is not limited to this, and the first detection unit 31 may be provided between the second switch 30 and the second system 8.

[0031] The coil 32 is provided on a path on the connection line 9 on the opposite side to the first system 7 with respect to the second switch 30. Specifically, the coil 32 is provided on the connection line 9 between the second switch 30 and the second system 8. The coil 32 is a storage unit that stores energy by the current flowing from the main battery 3. The coil 32 stores energy W (W=(1 / 2)LI 2 , L: inductance, I: current).

[0032] When the second switch 30 is turned OFF and the first system 7 and the second system 8 are disconnected, the coil 32 supplies power based on the stored energy W to the second load 6. The coil 32 is provided so as to be able to supply power to the second load 6 during the dead time from when the second switch 30 is turned OFF until when the first switch 21 is turned ON. The coil 32 is provided so as to be able to supply power to the second load 6 for several tens of μs.

[0033] The dead time is provided for the following reason. In the power supply device 1, if a power failure occurs in the first system 7 and the first switch 21 is turned ON before the first system 7 and the second system 8 are disconnected, a current flows from the backup battery 4 to the first system 7. In this case, the power that can be supplied from the backup battery 4 to the second load 6 in the power supply device 1 decreases. To prevent this, the power supply device 1 provides a dead time.

[0034] A loop line 12 is connected to the connection line 9. The loop line 12 is connected to the connection line 9 between the second switch 30 and the coil 32. The loop line 12 is provided with a diode 40 and a second detection unit 41.

[0035] The diode 40 is provided so that when the second switch 30 is turned OFF, that is, when the first system 7 and the second system 8 are disconnected, power based on the energy W stored in the coil 32 is supplied to the second load 6. The cathode of the diode 40 is connected to the connection line 9. The anode of the diode 40 is connected to GND.

[0036] The diode 40 is a supply unit that supplies power based on the energy W stored in the coil 32 to the second load 6 when the first system 7 and the second system 8 are disconnected. The diode 40 prevents current from flowing through the loop line 12 when the second switch 30 is ON or when the first switch 21 is ON.

[0037] The second detection unit 41 is a current sensor that detects a current flowing through the loop line 12. Specifically, the second detection unit 41 is a sensor that detects that a current has flowed through the diode 40. The second detection unit 41 is connected to the cathode side of the diode 40. That is, the second detection unit 41 is provided between the diode 40 and the connection line 9. The second detection unit 41 may be connected to the anode side of the diode 40.

[0038] The control device 10 controls the first switch 21 and the second switch 30 based on the current values ​​I1, I2 detected by the first detection unit 31 and the second detection unit 41.

[0039] Next, the control device 10 will be described with reference to Fig. 2. Fig. 2 is a block diagram of the control device 10 according to the embodiment. The control device 10 includes a control unit 50 and a storage unit 51. The storage unit 51 corresponds to, for example, a RAM or a data flash.

[0040] The control unit 50 includes, for example, a computer having a central processing unit (CPU), read only memory (ROM), random access memory (RAM), data flash, input / output ports, and various other circuits.

[0041] The CPU of the computer functions as an acquisition unit 52, a determination unit 53, and an instruction unit 54 of the control unit 50, for example, by reading and executing a program stored in the ROM.

[0042] At least one or all of the acquisition unit 52, determination unit 53, and instruction unit 54 of the control unit 50 can be configured with hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The acquisition unit 52, determination unit 53, and instruction unit 54 may be integrated or separated into multiple units.

[0043] The acquiring unit 52 acquires a signal related to the current value I1 detected by the first detecting unit 31. The acquiring unit 52 acquires a signal related to the current value I2 detected by the second detecting unit 41.

[0044] The determination unit 53 determines whether the current value I1 detected by the first detection unit 31 is equal to or less than a first predetermined value P1. When the current value I1 detected by the first detection unit 31 is equal to or less than the first predetermined value P1, the determination unit 53 determines that a power failure has occurred in the first system 7.

[0045] The determination unit 53 determines that a power failure has occurred in the second system 8 when the current value I1 detected by the first detection unit 31 is equal to or greater than the second predetermined value P2.

[0046] The determination unit 53 determines whether the current value I2 detected by the second detection unit 41 is equal to or greater than a third predetermined value P3. The third predetermined value P3 is a preset value, and is a value that can determine whether a current has flowed through the diode 40, i.e., the loop line 12. The third predetermined value P3 is a value that can determine whether or not power based on the energy W stored in the coil 32 has started to be supplied to the second load 6. When the current value I2 detected by the second detection unit 41 is equal to or greater than the third predetermined value P3, the determination unit 53 determines that power supply from the coil 32 to the second load 6 has started.

[0047] The instruction unit 54 generates an instruction signal for controlling the first switch 21 or the second switch 30 according to the result of the determination by the determination unit 53, and outputs the instruction signal to the first switch 21 or the second switch 30. As a result, the first switch 21 or the second switch 30 is operated and switched ON or OFF.

[0048] In addition, during normal operation when no power failure occurs in the first system 7 and the second system 8, the first switch 21 is OFF and the second switch 30 is ON.

[0049] When the current value I1 detected by the first detection unit 31 is equal to or less than the first predetermined value P1 or equal to or more than the second predetermined value P2, the instruction unit 54 generates an instruction signal for switching the second switch 30 from ON to OFF and outputs the signal to the second switch 30. This switches the second switch 30 from ON to OFF. That is, the first system 7 and the second system 8 are disconnected.

[0050] When the current value I2 detected by the second detection unit 41 becomes equal to or greater than the third predetermined value P3, the instruction unit 54 generates an instruction signal for switching the first switch 21 from OFF to ON, and outputs the instruction signal to the first switch 21. As a result, the first switch 21 switches from OFF to ON.

[0051] Next, power supply in the power supply device 1 according to the embodiment will be described.

[0052] First, power supply in a normal state where no power failure occurs in the first system 7 and the second system 8 will be described with reference to Fig. 3. Fig. 3 is a diagram showing power supply in a normal state.

[0053] In a normal state, the second switch 30 is ON and the first switch 21 is OFF. Therefore, power is supplied from the main battery 3 to the first load 5 via the first system 7. Also, power is supplied from the main battery 3 to the second load 6 via the first system 7, the connection line 9, and the second system 8. Furthermore, power is supplied from the main battery 3 to the backup battery 4 via the first system 7, the connection line 9, the second system 8, and the charging mechanism 20. Energy W is stored in the coil 32 provided in the connection line 9 by the current flowing through the connection line 9.

[0054] Since the loop line 12 is provided with a diode 40, no current flows through the loop line 12.

[0055] When a power failure occurs in the first system 7, the second switch 30 is switched from ON to OFF, as shown in FIG. 4A. FIG. 4A is a diagram (part 1) showing power supply when a power failure occurs in the first system 7. As a result, the first system 7 and the second system 8 are cut off. Energy W is stored in the coil 32, and when the second switch 30 is turned OFF, a power supply path is formed by the loop line 12. Therefore, power is supplied from the coil 32 to the second load 6 via the second system 8.

[0056] When power supply from the coil 32 to the second load 6 via the second system 8 starts, the current value I2 detected by the second detection unit 41 becomes equal to or greater than the third predetermined value P3. As a result, the first switch 21 is switched from OFF to ON, as shown in FIG. 4B. FIG. 4B is a diagram (part 2) showing power supply when a power failure occurs in the first system 7. When the first switch 21 is switched ON, power is supplied from the backup battery 4 to the second load 6 via the first switch 21 and the second system 8.

[0057] In this way, the power supply device 1 supplies power from the coil 32 to the second load 6 during the dead time from when the second switch 30 is turned OFF until when the first switch 21 is turned ON.

[0058] When a power failure occurs in the second system 8, the second switch 30 is switched from ON to OFF. This disconnects the first system 7 and the second system 8, and power is supplied from the main battery 3 to the first load 5 via the first system 7.

[0059] Next, a control process when a power failure occurs in the first system 7 or the second system 8 according to the embodiment will be described with reference to Fig. 5. Fig. 5 is a flowchart illustrating a control process when a power failure occurs in the first system 7 or the second system 8 according to the embodiment.

[0060] The control device 10 determines whether the current value I1 detected by the first detection unit 31 is equal to or less than a first predetermined value P1 (S100). If the current value I1 is greater than the first predetermined value P1 (S100: No), the control device 10 determines whether the current value I1 is equal to or greater than a second predetermined value P2 (S104).

[0061] When the current value I1 is smaller than the second predetermined value P2 (S104: No), the control device 10 determines that the second system 8 is normal, and ends the current process.

[0062] If the current value I1 is equal to or greater than the second predetermined value P2 (S104: Yes), the control device 10 determines that a power failure has occurred in the second system 8, and switches the second switch 30 from ON to OFF (S105).

[0063] If the current value I1 is equal to or less than the first predetermined value P1 (S100: Yes), the control device 10 determines that a power failure has occurred in the first system 7, and switches the second switch 30 from ON to OFF (S101).

[0064] The control device 10 determines whether the current value I2 detected by the second detection unit 41 is equal to or greater than the third predetermined value P3 (S102). If the current value I2 is not equal to or greater than the third predetermined value P3 (S102: No), the control device 10 repeats the process of step S102 until the current value I2 is equal to or greater than the third predetermined value P3.

[0065] When the current value I2 becomes equal to or greater than the third predetermined value P3 (S102: Yes), the control device 10 determines that power is being supplied to the second load 6, and switches the first switch 21 from OFF to ON (S103).

[0066] Next, the effects of the power supply device 1 according to the embodiment will be described.

[0067] The power supply device 1 includes a first system 7, a second system 8, a connection line 9, a second switch 30, a first switch 21, a coil 32, and a diode 40. The first system 7 supplies power from the main battery 3 to the first load 5. The second system 8 supplies power from the backup battery 4 to the second load 6. The connection line 9 connects the first system 7 and the second system 8. The second switch 30 is provided on the connection line 9, and disconnects the first system 7 and the second system 8 when a failure occurs in the first system 7. The first switch 21 connects the backup battery 4 and the second load 6 so that power is supplied from the backup battery 4 to the second load 6 when a failure occurs in the first system 7. The coil 32 is provided on a path opposite to the first system 7 with respect to the second switch 30, and stores energy W by a current flowing from the main battery 3. The diode 40 is provided so that power based on the energy W stored in the coil 32 is supplied to the second load 6 when the first system 7 and the second system 8 are disconnected.

[0068] As a result, when the second switch 30 is turned OFF and the first system 7 and the second system 8 are disconnected, the power supply device 1 can supply power to the second load 6 by the energy W stored in the coil 32. Therefore, the power supply device 1 can prevent the power supply to the second load 6 from being cut off during the period from when the second switch 30 is turned OFF to when the first switch 21 is turned ON.

[0069] The coil 32 is provided between the second switch 30 and the second system 8. The diode 40 is connected to the connection line 9 between the second switch 30 and the coil 32.

[0070] As a result, when the power supply device 1 cuts off the first system 7 and the second system 8 and turns on the first switch 21 to supply power from the backup battery 4 to the second load 6, the power supply device 1 can quickly supply power to the second load 6 with a simple configuration. Therefore, the power supply device 1 can prevent the power supply to the second load 6 from being cut off.

[0071] The power supply device 1 includes a second detection unit 41 and a control device 10. The second detection unit 41 detects that a current has flowed through the diode 40. When the second detection unit 41 detects that a current has flowed through the diode 40, the control device 10 operates the first switch 21 to supply power from the backup battery 4 to the second load 6 via the second system 8.

[0072] As a result, the power supply device 1 can turn on the first switch 21 after disconnecting the first system 7 and the second system 8 and reliably supplying power from the coil 32 to the second load 6. Therefore, the power supply device 1 can prevent power from being cut off to the second load 6 while providing a dead time.

[0073] In the power supply device 1 according to the modified example, the coil 32 may be provided in the second system 8 as shown in Fig. 6. Fig. 6 is a diagram showing a configuration example of the power supply device 1 according to the modified example. For example, the coil 32 is provided between the second load 6 and a connection point between the connection line 9 and the second system 8. In the power supply device 1 according to the modified example, the coil 32 may be provided in the second system 8 and the loop line 12 may be connected to the second system 8 as shown in Fig. 7. Fig. 7 is a diagram showing a configuration example of the power supply device 1 according to the modified example.

[0074] Note that the above-mentioned arrangement positions of the coil 32 and the loop line 12 are merely examples, and it is sufficient if, when the first system 7 and the second system 8 are cut off, power based on the energy W stored in the coil 32 can be supplied to the second load 6.

[0075] The power supply device 1 according to the modified example may not include the second detection unit 41, and may switch the first switch 21 from OFF to ON when a power failure occurs in the first system 7. Specifically, the power supply device 1 according to the modified example may switch the first switch 21 from OFF to ON a predetermined time after the second switch 30 is switched from ON to OFF. In other words, the power supply device 1 according to the modified example may operate the first switch 21 to supply power from the backup battery 4 to the second load 6 a predetermined time after the first system 7 and the second system 8 are disconnected.

[0076] The predetermined time is a time that is set in advance, and is a time during which the operation of the second load 6 can be continued by the energy W stored in the coil 32. In addition, the predetermined time is a time during which the power supply to the second load 6 is not cut off.

[0077] As a result, the power supply device 1 according to the modified example does not include a second detection unit 41, thereby reducing the number of components, and can prevent the power supply to the second load 6 from being cut off, similar to the above embodiment.

[0078] The power supply device 1 according to the modified example may not be provided with the charging mechanism 20, but may instead be provided with a first switch 21 in the second system 8, as shown in Fig. 8. Fig. 8 is a diagram showing an example of the configuration of the power supply device 1 according to the modified example.

[0079] The power supply device 1 according to the modified example turns the first switch 21 ON when charging the backup battery 4. Moreover, the power supply device 1 according to the modified example turns the first switch 21 OFF when charging of the backup battery 4 is completed. Then, when a power failure occurs in the first system 7 as described above and the first system 7 and the second system 8 are disconnected, the power supply device 1 according to the modified example switches the first switch 21 from OFF to ON after power is supplied from the coil 32 to the second load 6.

[0080] Thereby, the power supply device 1 according to the modified example can prevent the power supply to the second load 6 from being cut off, similar to the power supply device 1 according to the embodiment.

[0081] Note that the power supply device 1 according to the modified example may be provided with a diode instead of the charging mechanism 20. The diode allows current to flow from the main battery 3 to the backup battery 4 and prohibits current to flow from the backup battery 4 to the second load 6. The cathode of the diode is connected to the backup battery 4, and the anode of the diode is connected to the second system 8 on the second load 6 side.

[0082] Although the power supply device 1 according to the embodiment and the modified example has been described as a vehicle equipped with an automatic driving system as an example, the present invention is not limited to this. The power supply device 1 can be applied to a device capable of supplying power to a load from a backup battery in the event of a power failure.

[0083] 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]

[0084] 1 Power supply 2. Power generation equipment 3 Main battery (first battery) 4 Backup battery (second battery) 5 1st load 6 Second load 7 1st system 8 2nd system 9 Connection Lines 10 Control device 12 Loop Line 20 Charging mechanism 21 First switch (connection mechanism) 30 Second switch (shutoff mechanism) 31 First detection unit 32 Coil (storage section) 40 Diode (supply part) 41 Second detection unit (detection unit) 50 Control section 51 Storage section 52 Acquisition Department 53 Judgment section 54 Instruction section

Claims

1. a first system that supplies power from a first battery to a first load; a second system that supplies power from a second battery to a second load; a connection line connecting the first system and the second system; a cutoff mechanism that is provided in the connection line and connects the first system and the second system when no failure occurs in the first system, and cuts off the first system and the second system when a failure occurs in the first system; a connection mechanism provided in the second system and configured to connect the second battery and the second load such that, when a failure occurs in the first system, power is supplied from the second battery to the second load; a storage unit provided in the connection line between the interruption mechanism and the second system, the storage unit storing energy by a current flowing from the first battery; a supply unit that is provided so as to supply power based on the energy stored in the storage unit to the second load when the first system and the second system are interrupted; A power supply device comprising:

2. The supply unit is connected to the connection line between the storage unit and the cutoff mechanism.

2. The power supply device according to claim 1 .

3. A detection unit that detects that a current flows through the supply unit; a control device that operates the connection mechanism to supply power from the second battery to the second load via the second system when the detection unit detects that a current has flowed through the supply unit; 3. The power supply device according to claim 1, further comprising:

4. a control device that operates the connection mechanism to supply power from the second battery to the second load via the second system after a predetermined time has elapsed since the first system and the second system were disconnected by the disconnection mechanism; 3. The power supply device according to claim 1, further comprising:

5. The predetermined time is a time during which the operation of the second load can be continued by the energy stored in the storage unit.

5. The power supply device according to claim 4.

6. a step of connecting a first system, which supplies power from a first battery to a first load, and a second system, which supplies power from a second battery to a second load, to each other using a cutoff mechanism provided in a connection line connecting the first system and the second system when no failure occurs in the first system; a step of operating the power supply circuit when a failure occurs in the first system to cut off the first system and the second system; a step of supplying power to the second load from a storage unit that is provided in the connection line between the interruption mechanism and the second system and that stores energy using a current flowing from the first battery when a failure occurs in the first system; supplying power from the second battery to the second load after the power is supplied from the storage unit to the second load; A power supply control method comprising:

Images