Power control system

Abstract

A power supply control system controls a redundant power supply system, the redundant power supply system including a first power supply system and a second power supply system connected in parallel to a power supply unit. The first power supply system includes a first power supply and a first system. The second power supply system includes a second power supply and a second system. The power supply control system includes: a first switch, which is a MOSFET disposed between the power supply unit and the first power supply; a second switch, which is a MOSFET disposed between the power supply unit and the second power supply; a wiring configured to supply dark current from the first power supply to the second system; a normally open first relay disposed on the wiring; and a normally closed second relay disposed between the second power supply and the second switch.

Description

Technical Field

[0001] The invention relates to a power supply control system. Background Art

[0002] A redundant power supply system is known in which a first power supply system supplying power to a first motion system and a load and a second power supply system supplying power to a second motion system are connected to a power supply unit via first and second DC / DC converters (for example, see Patent Document 1).

[0003] Patent Document 1: JP-A-2020-24182

[0004] In the redundant power supply system described in Patent Document 1, since DC / DC converters are provided for a plurality of power supply systems, the size and weight of the entire system increase. Summary of the Invention

[0005] In view of the above circumstances, an object of the present invention is to provide a power supply control system capable of reducing the size and weight of a redundant power supply system and ensuring redundancy of a plurality of power supplies.

[0006] Aspects of non-limiting embodiments of the present disclosure relate to providing a power supply control system configured to control a redundant power supply system, the redundant power supply system including a first power supply system and a second power supply system connected in parallel to a power supply unit, the first power supply system including a first power supply and a first system powered by the first power supply, the second power supply system including a second power supply and a second system powered by the second power supply, the power supply control system including: a first switch, which is a MOSFET arranged between the power supply unit and the first power supply; a second switch, which is a MOSFET arranged between the power supply unit and the second power supply; a wiring configured to supply a dark current flowing from the first power supply to the second system; a first relay of a normally open type arranged on the wiring; and a second relay of a normally closed type arranged between the second power supply and the second switch.

[0007] According to the present invention, it is possible to reduce the size and weight of a redundant power supply system and ensure redundancy of a plurality of power supplies. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a diagram showing a vehicle-mounted redundant power supply system including a power supply control system according to an embodiment of the present invention.

[0009] Figure 2 It shows Figure 1 The timing diagram of the processing of the power supply control system is shown.

[0010] Figure 3 It shows Figure 1 A diagram showing the functionality of the power control system.

[0011] Figure 4 It shows Figure 1 A diagram showing the functionality of the power control system.

[0012] Figure 5 It shows Figure 1 A diagram showing the functionality of the power control system.

[0013] Figure 6 FIG. 1 is a diagram showing a vehicle-mounted redundant power supply system including a power supply control system according to another embodiment of the present invention.

[0014] Figure 7 FIG. 1 is a diagram showing a vehicle-mounted redundant power supply system including a power supply control system according to another embodiment of the present invention.

[0015] Figure 8 It shows Figure 7 The timing diagram of the processing of the power supply control system is shown.

[0016] Figure 9 It shows Figure 7 A diagram showing the functionality of the power control system.

[0017] Figure 10 It shows Figure 7 A diagram showing the functionality of the power control system.

[0018] Figure 11 It shows Figure 7 A diagram showing the functionality of the power control system. DETAILED DESCRIPTION

[0019] Hereinafter, the present invention will be described based on preferred embodiments. The present invention is not limited to the embodiments described below, and the embodiments described below can be appropriately modified without departing from the gist of the present invention. In addition, in the embodiments described below, although the illustration and description of some configurations are omitted, it goes without saying that known or well-known technologies are appropriately applied to the details of the omitted technologies within the scope of not contradicting the contents described below.

[0020] Figure 1 FIG. 1 is a diagram showing a vehicle-mounted redundant power supply system 1 including a power supply control system 10 according to an embodiment of the present invention. Figure 1 As shown, the redundant power supply system 1 includes a first power supply system 1A, a second power supply system 1B, a power supply unit 4 and a power supply control system 10 .

[0021] The first power supply system 1A includes a first battery 2, a first motion system 7 and a load L. The second power supply system 1B includes a second battery 3 and a second motion system 8. The first battery 2 is a lead-acid battery (lead storage battery) with a rated voltage of 12V. The second battery 3 is a lead-acid battery with a rated voltage of 12V or other secondary battery having charging and discharging characteristics similar to those of a lead-acid battery. Examples of other secondary batteries may include an assembled battery in which ten nickel metal hydride batteries are connected in series, an assembled battery in which four iron phosphate type lithium ion batteries are connected in series, and an assembled battery in which five lithium titanate batteries are connected in series. The negative terminals of the first battery 2 and the second battery 3 are connected to the vehicle body ground via a ground cable EC. When the second battery 3 is an assembled battery, it is preferable to appropriately perform variation correction for correcting variations in the state of charge between the battery cells.

[0022] The first motion system 7 includes onboard equipment related to vehicle behavior (driving, turning, braking, etc.). These onboard equipment include steering, brakes, and automated driving assistance devices. The load L includes onboard equipment unrelated to vehicle behavior, including headlights and windshield wipers. The first motion system 7 and the load L are connected to the positive terminal of the first battery 2 via a first connection H1 and a sixth connection H6.

[0023] The second motion system 8 redundantly includes onboard equipment related to vehicle behavior similar to the first motion system 7. The second motion system 8 is connected to the positive terminal of the second battery 3 through the second connection H2 and the seventh connection H7.

[0024] The power supply unit 4 includes a power output unit 5 and a DC / DC converter 6. The power output unit 5 includes a high-voltage (HV) power supply such as 48V and a generator, and outputs high-voltage power to the DC / DC converter 6. The DC / DC converter 6 steps down the high-voltage power output from the power output unit 5 and outputs the stepped-down high-voltage power to the power supply control system 10.

[0025] The power supply control system 10 includes a first switch 11, a second switch 12, a third switch 13, a first relay 14, a second relay 15, a protector 16, and a control device 20. The first switch 11 is connected to the starting end of the first wiring H1. The second switch 12 is connected to the starting end of the second wiring H2.

[0026] The first switch 11 and the second switch 12 are N-channel metal oxide semiconductor field effect transistors (MOSFETs). The starting end of the first wiring H1 is connected to the drain D of the first switch 11, and the starting end of the second wiring H2 is connected to the drain D of the second switch 12. The source S of the first switch 11 and the source S of the second switch 12 are connected to each other via a third wiring H3.

[0027] The third switch 13 is an N-channel MOSFET. The source S of the third switch 13 is connected to the connection point P1 of the third connection H3 via the fourth connection H4. In other words, the source S of the third switch 13 is connected to the source S of the first switch 11 and the second switch 12.

[0028] The drain D of the third switch 13 is connected to the output terminal of the DC / DC converter 6 via the fifth connection H5. That is, the first battery 2, the first motion system 7, and the load L are connected to the output terminal of the DC / DC converter 6 via the first switch 11 and the third switch 13. In addition, the second battery 3 and the second motion system 8 are connected to the output terminal of the DC / DC converter 6 via the second switch 12 and the third switch 13.

[0029] The positive terminal of the first battery 2 is connected to the connection point P2 of the first connection H1 via the sixth connection H6. Furthermore, the positive terminal of the second battery 3 is connected to the connection point P3 of the second connection H2 via the seventh connection H7. A second relay 15 is provided in the seventh connection H7. The second relay 15 is a normally closed relay that is closed when the vehicle ignition is off and closed when the vehicle ignition is on.

[0030] Examples of the first relay 14 and the second relay 15 may include a mechanical relay and a semiconductor relay such as the MOSFET shown. When the second relay 15 is a semiconductor relay, the second relay 15 may be provided in the ground cable EC connecting the negative terminal of the second battery 3 and the vehicle body ground.

[0031] The first wiring H1 and the second wiring H2 are connected via an eighth wiring H8. A connection point P4 between the first wiring H1 and the eighth wiring H8 is provided between a connection point P5 of the first motion system 7 in the first wiring H1 and a connection point P2 of the first battery 2. Furthermore, a connection point P6 between the second wiring H2 and the eighth wiring H8 is provided between a connection point P7 of the second motion system 8 in the second wiring H2 and a connection point P3 of the second battery 3.

[0032] The first relay 14 and the protector 16 are provided in the eighth connection H8. The first relay 14 is a normally open relay that turns on when the vehicle ignition is off and turns off when the vehicle ignition is on. The eighth connection H8 is provided to supply dark current flowing from the first battery 2 to the second motion system 8 when the vehicle ignition is off. Furthermore, the protector 16 is provided between the first relay 14 and the connection point P4 to protect the first relay 14 and cut off dark current exceeding a normal value. The protector 16 can be provided between the first relay 14 and the connection point P6.

[0033] When the ignition of the vehicle is turned on, the first to third switches 11 to 13 are turned on, the first relay 14 is turned off, and the second relay 15 is turned on, thereby supplying power from the power supply unit 4 or the first battery 2 to the first motion system 7 and the load L, and supplying power from the power supply unit 4 or the second battery 3 to the second motion system 8. On the other hand, when the ignition of the vehicle is turned off, the first to third switches 11 to 13 are turned off, the first relay 14 is turned on, and the second relay 15 is turned off, thereby supplying power from the first battery 2 to the first motion system 7, the load L, and the second motion system 8.

[0034] The first switch 11, the second switch 12, and the third switch 13, each of which is an N-channel MOSFET, cut off the current flowing from the drain D to the source S when in the off state. The first switch 11 in the off state cuts off the current flowing from the first battery 2. The second switch 12 in the off state cuts off the current flowing from the second battery 3. The third switch 13 in the off state cuts off the current flowing from the power supply unit 4.

[0035] Here, when a gate voltage is applied from a driver (not shown), the first switch 11, the second switch 12, and the third switch 13 are in the on state, and current flows from the drain D to the source s. In addition, even in a state where no gate voltage is applied from the driver, the first switch 11, the second switch 12, and the third switch 13 are in the on state, where when the voltage on the source S side is higher than the voltage on the drain D side, current flows from the source S to the drain D. On the other hand, when the gate voltage is not applied from the driver and the voltage on the drain D side is higher than the voltage on the source S side, the first switch 11, the second switch 12, and the third switch 13 are in the off state, where the current from the source S to the drain D is cut off. In the following description, the state where the first switch 11, the second switch 12, and the third switch 13 are turned on by applying a gate voltage from the driver is referred to as a forced on state. On the other hand, the state where the first switch 11, the second switch 12, and the third switch 13 are turned on when no gate voltage is applied from the driver is referred to as an on state. In addition, when no gate voltage is applied from the driver, a state in which the first switch 11 , the second switch 12 , and the third switch 13 are turned off is referred to as an off state.

[0036] When the voltage on the source S side of the first switch 11 is higher than the voltage on the drain D side of the first switch 11, the first switch 11 is in the on state, and current flows from the power supply unit 4 side to the first power supply system 1A side. On the other hand, when the voltage on the drain D side of the first switch 11 is higher than the voltage on the source S side of the first switch 11, the first switch 11 is in the off state to cut off the current flowing from the power supply unit 4 side.

[0037] When the voltage on the source S side of the second switch 12 is higher than the voltage on the drain D side of the second switch 12, the second switch 12 is in the on state, and current flows from the power supply unit 4 side to the second power supply system 1B side. On the other hand, when the voltage on the drain D side of the second switch 12 is higher than the voltage on the source S side of the second switch 12, the second switch 12 is in the off state to cut off the current flowing from the power supply unit 4 side.

[0038] When the voltage on the source S side of the third switch 13 is higher than the voltage on the drain D side of the third switch 13, the third switch 13 is in the on state, and current flows from the first power supply system 1A side and the second power supply system 1B side to the power supply unit 4 side. On the other hand, when the voltage on the drain D side of the third switch 13 is higher than the voltage on the source S side of the third switch 13, the third switch 13 is in the off state, thereby shutting off the current flowing from the first power supply system 1A side and the second power supply system 1B side.

[0039] The control device 20 includes a driver (not shown) and a microprocessing unit (MPU). The driver is a gate drive circuit including a resistor, a capacitor, etc., and switches the gate drive voltage applied to the first switch 11, the second switch 12, and the third switch 13 to a voltage that can be set to a forced on state or a voltage that can be set to an on state and an off state in response to a control signal output from the MPU.

[0040] The MPU outputs a control signal to the driver for switching the forced on state / on or off state of the first switch 11, the second switch 12, and the third switch 13 in accordance with an on / off instruction from an onboard electronic control unit (ECU, not shown). In addition, the MPU performs control for switching the first relay 14, the second relay 15, and the DC / DC converter 6 on / off.

[0041] Figure 2 It shows Figure 1 The timing diagram of the processing of the power supply control system 10 is shown. Figures 3 to 5 It shows Figure 1 FIG. 1 is a diagram showing the functions of the power supply control system 10. Figure 2As shown in the timing diagram, when the ignition (IG) is off, the output of the DC / DC converter 6 is turned off, the first to third switches 11 to 13 are in the off state, the first relay 14 is in the on state, and the second relay 15 is in the off state. When the ignition is off, the first switch 11, in the off state, blocks the current flowing from the first battery 2, the second switch 12, in the off state, blocks the current flowing from the second battery 3, and the second relay 15 blocks the current flowing from the second battery 3. Therefore, when the ignition is off, dark current is supplied from the first battery 2 to the first motion system 7, load L, and second motion system 8, but dark current is not supplied from the second battery 3 to the first motion system 7, load L, and second motion system 8.

[0042] When the ignition is turned on, the output of the DC / DC converter 6 increases to a predetermined value (e.g., a nominal voltage of 12V), the first to third switches 11 to 13 are forced on, the first relay 14 is off, and the second relay 15 is on. When the ignition is turned on, the first to third switches 11 to 13, in their forced on state, allow current to flow in both directions as long as there is no voltage drop due to a ground fault, etc. Therefore, when the ignition is turned on, the first and second batteries 2 and 3 are charged by the power supplied from the DC / DC converter 6, power is supplied from the DC / DC converter 6 or the first battery 2 to the first motion system 7 and the load L, and power is supplied from the DC / DC converter 6 or the second battery 3 to the second motion system 8. Generally, the state after the ignition is turned on remains unchanged.

[0043] Here, since the charging characteristics of the first battery 2 and the second battery 3 are similar to each other, the first battery 2 and the second battery 3 are in a similar state of charge by supplying power of the same voltage from the common DC / DC converter 6. When the variation in the state of charge between the first battery 2 and the second battery 3 is large, current flows from one battery to the other, which complicates charging control.

[0044] The control device 20 detects the voltage between the DC / DC converter 6 and the third switch 13. When the voltage becomes an abnormally high voltage exceeding the allowable value, the control device 20 sets the third switch 13 to the off state. Therefore, the third switch 13 in the off state cuts off the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 side. Figure 3 As shown, nominal 12V power is supplied from the first battery 2 to the first motion system 7 and the load L, and nominal 12V power is supplied from the second battery 3 to the second motion system 8 .

[0045] like Figure 2As shown in the timing diagram, when a ground fault occurs between the DC / DC converter 6 and the third switch 13, the voltage between the DC / DC converter 6 and the third switch 13 drops to or below a predetermined value (e.g., 6V) below the nominal 12V. When the voltage between the DC / DC converter 6 and the third switch 13 drops to or below the predetermined value below the nominal 12V, the control device 20 shuts off the output of the DC / DC converter 6 and sets the first switch 11 and the second switch 12 to the off state. Consequently, the supply voltage from the first battery 2 to the first motion system 7 and the load L momentarily drops, then returns to the nominal 12V, maintaining normal operation of the first motion system 7 and the load L. Furthermore, the supply voltage from the second battery 3 to the second motion system 8 momentarily drops, then returns to the nominal 12V, maintaining normal operation of the second motion system 8.

[0046] Instead of detecting a ground fault between DC / DC converter 6 and third switch 13 based on the voltage between the two switches, a ground fault between DC / DC converter 6 and third switch 13 can be detected based on the current value of the current flowing from first battery 2 and second battery 3 to first to third switches 11 to 13. When a ground fault occurs between DC / DC converter 6 and third switch 13, excessive current flows from first battery 2 and second battery 3 to first to third switches 11 to 13. Therefore, when an excessive current value exceeding a permissible value is detected, first switch 11 and second switch 12 can be turned off.

[0047] When a ground fault occurs in the first power supply system 1A, the voltage of the first power supply system 1A drops to or below a predetermined value (for example, 6V) lower than the nominal 12V. When the voltage of the first power supply system 1A drops to or below a predetermined value lower than the nominal voltage 12V, the control device 20 sets the second switch 12 and the third switch 13 to the off state. The second switch 12 in the off state cuts off the current flowing from the drain D to the source S, that is, the current flowing from the second battery 3 side. Here, since the first relay 14 is in the off state, the second power supply system 1B is disconnected from the first power supply system 1A where the ground fault occurs. Therefore, as Figure 4 As shown, the power supply from the DC / DC converter 6 or the first battery 2 to the first motion system 7 is stopped, and the power supply from the second battery 3 to the second motion system 8 is started, so that the second motion system 8 operates normally.

[0048] When a ground fault occurs in the first power supply system 1A, the third switch 13, in the off state, blocks the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 to the ground fault point in the first power supply system 1A. Thus, the DC / DC converter 6 is protected. Instead of detecting a ground fault in the first power supply system 1A based on the voltage of the first power supply system 1A, a ground fault in the first power supply system 1A can be detected based on the current value flowing from the second battery 3 to the second switch 12. When a ground fault occurs in the first power supply system 1A, excessive current flows from the second battery 3 to the second switch 12. Therefore, when an excessive current value exceeding the allowable value is detected, the second switch 12 can be turned off.

[0049] like Figure 2 As shown in the timing diagram of , when a ground fault occurs in the second power supply system 1B, the voltage of the second power supply system 1B drops to or below a predetermined value (for example, 6V) lower than the nominal 12V. When the voltage of the second power supply system 1B drops to or below a predetermined value lower than the nominal voltage 12V, the control device 20 sets the first switch 11 and the third switch 13 to the off state. The first switch 11 in the off state cuts off the current flowing from the drain D to the source S, that is, the current flowing from the first battery 2 side. Here, since the first relay 14 is turned off, the first power supply system 1A is disconnected from the second power supply system 1B where the ground fault occurs. Therefore, as Figure 5 As shown, the power supply from the DC / DC converter 6 or the second battery 3 to the second motion system 8 is stopped, and the power supply from the first battery 2 to the first motion system 7 and the load L is started, so that the first motion system 7 and the load L operate normally.

[0050] When a ground fault occurs in the second power system 1B, the third switch 13, in its off state, blocks the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 to the ground fault point in the second power system 1B. This protects the DC / DC converter 6. Instead of detecting a ground fault in the second power system 1B based on the voltage of the second power system 1B, a ground fault in the second power system 1B can be detected based on the current value flowing from the first battery 2 to the first switch 11. When a ground fault occurs in the second power system 1B, excessive current flows from the first battery 2 to the first switch 11. Therefore, when an excessive current value exceeding the permissible value is detected, the first switch 11 can be turned off.

[0051] like Figure 2As shown in the timing diagram, when a ground fault occurs between the first switch 11 and the second and third switches 12 and 13, the voltage between the first and second switches 11 and 12 and 13 drops to or below a predetermined value (e.g., 6V) below the nominal 12V. When the voltage between the first and second switches 11 and 12 and third switches 13 drops to or below the predetermined value below the nominal 12V, the control device 20 sets the first to third switches 11 to 13 to the off state and shuts off the output from the DC / DC converter 6. Consequently, the supply voltage from the first battery 2 to the first motion system 7 and load L momentarily drops, then returns to the nominal 12V, maintaining normal operation of the first motion system 7 and load L. Furthermore, the supply voltage from the second battery 3 to the second motion system 8 momentarily drops, then returns to the nominal 12V, maintaining normal operation of the second motion system 8.

[0052] Instead of detecting a ground fault occurring between the first switch 11 and the second and third switches 12, 13 based on the voltages therebetween, a ground fault occurring between the first switch 11 and the second and third switches 12, 13 can be detected based on the current value of the current flowing between the first and second switches 11, 13. When a ground fault occurs between the first switch 11 and the second and third switches 12, 13, an excessive current flows between the first and second switches 11, 13. Therefore, when an excessive current value exceeding a permissible value is detected, the first and third switches 11, 13 can be turned off.

[0053] The control device 20 switches the second relay 15 on and off depending on the charge and discharge status of the second battery 3. For example, when the second battery 3 transitions to an overcharged state, when the second battery 3 is discharging at a high current exceeding the allowable value, when the second battery 3 transitions to an overdischarged state where the charge capacity of the second battery 3 falls below the lower limit, or when the temperature of the second battery 3 is high and exceeds the allowable value, the control device 20 sets the second relay 15 to the off state. In this case, power redundancy is lost. Therefore, when the second relay 15 is set to the off state, the control device 20 notifies the control device powered by the second battery 3 and performs redundant operation to address any abnormalities in the second battery 3.

[0054] In this embodiment, since the first battery 2 is a lead-acid battery, no relay is provided for protecting, for example, overcharge of the first battery 2. However, when the first battery 2 is a secondary battery other than a lead-acid battery similarly to the second battery 3, a relay for protecting the first battery 2 is preferably provided in the sixth wiring H6.

[0055] As described above, according to the power supply control system 10 of this embodiment, in a redundant power supply system 1 that supplies power from a single DC / DC converter 6 to both the first power supply system 1A and the second power supply system 1B, even if a fault, such as a ground fault, occurs in either of the first power supply system 1A and the second power supply system 1B, the other power supply system can operate normally. Furthermore, even if the output voltage of the DC / DC converter 6 abnormally increases, or if a fault, such as a ground fault, occurs between the DC / DC converter 6 and the first and second switches 11 and 12, the first and second power supply systems 1A and 1B can operate normally by supplying power from the first battery 2 to the first motion system 7 and the load L, and from the second battery 3 to the second motion system 8. Therefore, by providing only one DC / DC converter 6, the size and weight of the redundant power supply system 1 can be reduced, while ensuring redundancy in multiple power supplies.

[0056] When the ignition is off, discharge from the second battery 3 is stopped by the normally closed second relay 15, and dark current can then be supplied from the first battery 2 to the second motion system 8 via the normally open first relay 14. Furthermore, when the ignition is on, since the first relay 14 is off and the second relay 15 is on, the first power supply system 1A and the second power supply system 1B can be disconnected from each other by switching the first switch 11 and the second switch 12 on and off. Therefore, when a fault, such as a ground fault, occurs in either the first power supply system 1A or the second power supply system 1B, one power supply system can be disconnected from the other power supply system where the fault occurred and can operate normally.

[0057] Figure 6 1 is a diagram showing an in-vehicle redundant power supply system 101 including a power supply control system 110 according to another embodiment of the present invention. The same reference numerals are given to configurations similar to those of the above-described embodiment, and the description of the above-described embodiment is incorporated.

[0058] like Figure 6 As shown, in addition to the load L1 provided in the first power supply system 1A, the redundant power supply system 101 further includes a load L2 connected to the output terminal of the DC / DC converter 6 via a ninth connection H9. The load L2 is a load directly powered by the DC / DC converter 6 and is not provided in the redundant configuration.

[0059] The power supply control system 110 includes a first relay 114 having two poles, rather than the first relay 14 having one pole. The first relay 114 is provided across the eighth connection H8 connecting the first connection H1 and the second connection H2, and the tenth connection H10 connecting the eighth connection H8 and the ninth connection H9. When the ignition is turned off, power is supplied from the first battery 2 to the second motion system 8 and the load L2 via the first relay 114.

[0060] Here, by making the load L2 a system separate from the second power supply system 1B, the value of the current flowing through the second switch 12 can be reduced, and the size of the second switch 12 can be reduced.

[0061] Figure 7 2 is a diagram showing a vehicle-mounted redundant power supply system 201 including a power supply control system 210 according to another embodiment of the present invention. The same reference numerals are given to configurations similar to those of the above-described embodiment, and the description of the above-described embodiment is incorporated.

[0062] like Figure 7 As shown, redundant power supply system 201 includes a first power supply system 201A, a second power supply system 201B, a power supply unit 4, and a power supply control system 210. First power supply system 201A includes a first battery 2, a first motion system 7, and a load 1. Second power supply system 201B includes a second battery 3 and a second motion system 8.

[0063] The power supply control system 210 includes a first switch 211, a second switch 212, a first relay 14, a second relay 15, a protector 16, a housing 217, and a control device 220. The first switch 211 is connected to the starting end of the first wiring H1. The second switch 212 is connected to the starting end of the second wiring H2.

[0064] The first switch 211 and the second switch 212 are N-channel MOSFETs. The starting end of the first wiring H1 is connected to the source S of the first switch 211, and the starting end of the second wiring H2 is connected to the source S of the second switch 212. The drain D of the first switch 211 and the drain D of the second switch 212 are connected to each other via a third wiring H3.

[0065] The connection point P1 of the third connection H3 and the output terminal of the DC / DC converter 6 are connected via the fifth connection H5. That is, the first battery 2, the first motion system 7, and the load L are connected to the output terminal of the DC / DC converter 6 via the first switch 211. In addition, the second battery 3 and the second motion system 8 are connected to the output terminal of the DC / DC converter 6 via the second switch 212.

[0066] The first switch 211 and the second switch 212 , which are N-channel MOSFETs, cut off the current flowing from the drain D to the source S in the off state. The first switch 211 and the second switch 212 in the off state cut off the current flowing from the DC / DC converter 6 side.

[0067] Here, when a gate voltage is applied from a driver (not shown), the first switch 211 and the second switch 212 are in the on state, and current flows from the drain D to the source S. Furthermore, even when no gate voltage is applied from the driver, when the voltage on the source S side is higher than the voltage on the drain D side, the first switch 211 and the second switch 212 are in the on state, where current flows from the source S to the drain D. On the other hand, when no gate voltage is applied from the driver and the voltage on the drain D side is higher than the voltage on the source S side, the first switch 211 and the second switch 212 are in the off state, where current flowing from the source S to the drain D is cut off. In the following description, the state in which the first switch 211 and the second switch 212 are turned on by applying a gate voltage from the driver is referred to as a forced on state. On the other hand, the state in which the first switch 211 and the second switch 212 are turned on when no gate voltage is applied from the driver is referred to as an on state. Furthermore, the state in which the first switch 211 and the second switch 212 are turned off when no gate voltage is applied from the driver is referred to as an off state.

[0068] When the voltage on the source S side of the first switch 211 is higher than the voltage on the drain D side of the first switch 211, the first switch 211 is in the on state, and current flows from the first battery 2 side to the DC / DC converter 6 side. On the other hand, when the voltage on the drain D side of the first switch 211 is higher than the voltage on the source S side of the first switch 211, the first switch 211 is in the off state to cut off the current flowing from the first battery 2 side.

[0069] When the voltage on the source S side of the second switch 212 is higher than the voltage on the drain D side of the second switch 212, the second switch 212 is in the on state, and current flows from the second battery 3 side to the DC / DC converter 6 side. On the other hand, when the voltage on the drain D side of the second switch 212 is higher than the voltage on the source S side of the second switch 212, the second switch 212 is in the off state to cut off the current flowing from the second battery 3 side.

[0070] Here, power supply control system 210 includes a housing 217 that houses first switch 211, second switch 212, DC / DC converter 6, third connection H3, and fifth connection H5. Housing 217 is insulated from the vehicle body ground. This improves the insulation between first switch 211, second switch 212, DC / DC converter 6, third connection H3, and fifth connection H5 and the vehicle body ground, and prevents ground faults from occurring between first switch 211, second switch 212, and DC / DC converter 6.

[0071] The DC / DC converter 6 includes a switch (not shown) therein. When the control device 220 sets the switch of the DC / DC converter 6 to the off state, the output of the DC / DC converter 6 is turned off, and the current flowing from the first switch 211 side and the second switch 212 side to the DC / DC converter 6 side is cut off. Preferably, the DC / DC converter 6 has a function of protecting the DC / DC converter 6 from a short-circuit fault that occurs therein.

[0072] The control device 220 includes a driver (not shown) and an MPU (not shown). The driver is a gate drive circuit including a resistor, a capacitor, etc., and switches the gate drive voltage applied to the first switch 211 and the second switch 212 to a voltage that can be set to a forced on state or a voltage that can be set to an on state and an off state in response to a control signal output from the MPU.

[0073] The MPU outputs a control signal to the driver for switching the forced on state / on or off state of the first switch 211 and the second switch 212 according to an on / off instruction from the vehicle ECU (not shown). In addition, the MPU performs control for switching the switches of the first relay 14, the second relay 15, and the DC / DC converter 6 on / off.

[0074] Figure 8 It shows Figure 7 The timing diagram of the processing of the power supply control system 210 is shown. Figures 9 to 11 It shows Figure 7 FIG. 2 is a diagram showing the functionality of the power control system 210. Figure 8 As shown in the timing diagram, when the ignition (IG) is off, the output of the DC / DC converter 6 is turned off, the first switch 211 and the second switch 212 are in the off state, the first relay 14 is in the on state, and the second relay 15 is in the off state. When the ignition is off, the off-state first switch 211 and the second switch 212 cut off the current flowing from the DC / DC converter 6, and the second relay 15 cuts off the current flowing from the second battery 3. Therefore, when the ignition is off, dark current is supplied from the first battery 2 to the first motion system 7, the load L, and the second motion system 8, but dark current is not supplied from the second battery 3 to the first motion system 7, the load L, and the second motion system 8.

[0075] When the ignition is turned on, the output of the DC / DC converter 6 increases to a predetermined value (e.g., a nominal voltage of 12V), the first switch 211 and the second switch 212 are forced on, the first relay 14 is off, and the second relay 15 is on. When the ignition is turned on, the first switch 211 and the second switch 212, in the forced on state, allow current to flow in both directions as long as there is no voltage drop due to a ground fault, etc. Therefore, when the ignition is turned on, the first battery 2 and the second battery 3 are charged by the power supply from the DC / DC converter 6, power is supplied from the DC / DC converter 6 or the first battery 2 to the first motion system 7 and the load L, and power is supplied from the DC / DC converter 6 or the second battery 3 to the second motion system 8. Generally, the state after the ignition is turned on remains unchanged.

[0076] The control device 220 detects the voltage between the first switch 211 and the second switch 212 and the DC / DC converter 6. When the voltage becomes an abnormally high voltage exceeding the allowable value, the control device 220 sets the first switch 211 and the second switch 212 to the off state. Therefore, the first switch 211 and the second switch 212 in the off state cut off the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 side. Therefore, as Figure 9 As shown, nominal 12V power is supplied from the first battery 2 to the first motion system 7 and the load L, and nominal 12V power is supplied from the second battery 3 to the second motion system 8 .

[0077] like Figure 8 As shown in the timing diagram of , when a ground fault occurs in the first power supply system 201A, the voltage of the first power supply system 201A drops to or below a predetermined value (for example, 6V) lower than the nominal 12V. When the voltage of the first power supply system 201A drops to or below a predetermined value lower than the nominal voltage 12V, the control device 220 sets the first switch 211 to the off state. The first switch 211 in the off state cuts off the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 side. Here, since the first relay 14 is in the off state, the second power supply system 201B is disconnected from the first power supply system 201A where the ground fault occurs. Therefore, as Figure 10 As shown, the power supply from the DC / DC converter 6 or the first battery 2 to the first motion system 7 is stopped, and the power supply from the DC / DC converter 6 or the second battery 3 to the second motion system 8 is started, so that the second motion system 8 operates normally.

[0078] Instead of detecting a ground fault occurring in first power system 201A based on the voltage of first power system 201A, a ground fault occurring in first power system 201A can be detected based on the current value of the current flowing from second battery 3 to first switch 211 and second switch 212. When a ground fault occurs in first power system 201A, excessive current flows from second battery 3 to first switch 211 and second switch 212. Therefore, when an excessive current value exceeding the allowable value is detected, first switch 211 can be turned off.

[0079] like Figure 8 As shown in the timing diagram of , when a ground fault occurs in the second power supply system 201B, the voltage of the second power supply system 201B drops to or below a predetermined value (for example, 6V) lower than the nominal 12V. When the voltage of the second power supply system 201B drops to or below a predetermined value lower than the nominal voltage 12V, the control device 220 sets the second switch 212 to the off state. The second switch 212 in the off state cuts off the current flowing from the drain D to the source S, that is, the current flowing from the DC / DC converter 6 side. Here, since the first relay 14 is in the off state, the first power supply system 201A is disconnected from the second power supply system 201B where the ground fault occurs. Therefore, as Figure 11 As shown, the power supply from the DC / DC converter 6 or the second battery 3 to the second motion system 8 is stopped, and the power supply from the DC / DC converter 6 or the first battery 2 to the first motion system 7 and the load L is started, so that the first motion system 7 and the load L operate normally.

[0080] Instead of detecting a ground fault occurring in second power supply system 1B based on the voltage of second power supply system 1B, a ground fault occurring in second power supply system 1B can be detected based on the current value of the current flowing from first battery 2 to first switch 211 and second switch 212. When a ground fault occurs in second power supply system 201B, excessive current flows from first battery 2 to first switch 211 and second switch 212. Therefore, when an excessive current value exceeding the allowable value is detected, second switch 212 can be turned off.

[0081] As described above, according to power supply control system 210 of this embodiment, in redundant power supply system 201, which supplies power from a single DC / DC converter 6 to both first power supply system 201A and second power supply system 201B, even if a fault, such as a ground fault, occurs in either first power supply system 1A or second power supply system 1B, the other power supply system can operate normally. Furthermore, when the output voltage of DC / DC converter 6 abnormally increases, power is supplied from first battery 2 to first motion system 7 and load L, and power is supplied from second battery 3 to second motion system 8, allowing first power supply system 1A and second power supply system 1B to operate normally. Therefore, by providing a single DC / DC converter 6 and omitting third switch 13 of the above-described embodiment, the size and weight of redundant power supply system 201 can be reduced, while ensuring redundancy of multiple power supplies.

[0082] Since the insulation between the first switch 211 and the second switch 212 and the DC / DC converter 6 to the vehicle body ground is strengthened, a fault such as a ground fault can be prevented from occurring between the first switch 211 and the second switch 212 and the DC / DC converter 6, the third switch 13 of the above embodiment can be omitted, and then redundancy of multiple power supplies can be ensured.

[0083] Although the present invention has been described above based on the embodiments, the present invention is not limited to the above embodiments, and the above embodiments may be modified or known or well-known technologies may be appropriately combined without departing from the gist of the present invention.

[0084] For example, in the above embodiment, the first to third switches 11, 12, 13, 211, and 212, which are MOSFETs, are N-channel MOSFETs, but the first to third switches 11, 12, 13, 211, and 212 may be P-channel MOSFETs. In this case, the positional relationship between the source S and the drain D may be reversed from that of the above embodiment.

[0085] In addition, in the above-mentioned embodiment, the high-voltage power output unit 5 and the DC / DC converter 6 are provided as the power supply unit 4, but for example, an AC generator may be provided as the power output unit 5, and a voltage conversion unit for reducing the high-voltage power, such as a DC / DC converter, may not be provided.

[0086] Here, the features of the embodiment of the power supply control system according to the present disclosure described above will be briefly summarized and listed in the following [1] to [7].

[0087] [1] A power supply control system configured to control a redundant power supply system, the redundant power supply system including a first power supply system (1A, 201A) and a second power supply system (1B, 201B) connected in parallel to a power supply unit (4), the first power supply system (1A, 201A) including a first power supply (2) and a first system (7) supplied with power from the first power supply (2), the second power supply system (1B, 201B) including a second power supply (3) and a second system (8) supplied with power from the second power supply (3), the power supply control system comprising:

[0088] a first switch (11, 211) which is a MOSFET provided between the power supply unit (4) and the first power source (2);

[0089] a second switch (12, 212) which is a MOSFET provided between the power supply unit (4) and the second power supply (3);

[0090] a wiring (H8) configured to supply a dark current flowing from the first power source (2) to the second system (8);

[0091] a first relay (14, 114) of a normally open type, provided on the connection (H8); and

[0092] A normally closed second relay (15) is provided between the second power source (3) and the second switch (12, 212).

[0093] [2] The power supply control system according to [1] further comprises:

[0094] a third switch (13, 213) as a MOSFET, the third switch (13, 213) being provided between the first switch (11, 211) and the power supply unit (4) and between the second switch (12, 212) and the power supply unit (4), the third switch (13, 213) being configured to cut off a current flowing from one side of the power supply unit (4) to one side of the first power supply system (1A, 201A) and one side of the second power supply system (1B, 201B) when the third switch (13, 213) is in an off state;

[0095] wherein in an off state of the first switch (11, 211), the first switch (11, 211) cuts off the current flowing from one side of the first power supply system (1A, 201A) to one side of the power supply unit (4); and

[0096] In the off state of the second switch (12, 212), the second switch (12, 212) cuts off the current flowing from one side of the second power supply system (1B, 201B) to one side of the power supply unit (4).

[0097] [3] According to the power supply control system of [2] above,

[0098] wherein the first switch (11, 211), the second switch (12, 212) and the third switch (13, 213) are N-channel MOSFETs; and

[0099] The source of the first switch (11, 211), the source of the second switch (12, 212), and the source of the third switch (13, 213) are connected to each other, the drain of the first switch (11, 211) is connected to the first power supply (2) and the first system (7), the drain of the second switch (12, 212) is connected to the second power supply (3) and the second system (8), and the drain of the third switch (13, 211) is connected to the power supply unit (4).

[0100] [4] The power supply control system according to [2] or [3] above, further comprising:

[0101] A control unit (220) configured to control the first switch (211) and the second switch (212),

[0102] wherein when the voltage of the first power supply system (201A) is lower than a predetermined value or the current value of the current flowing from the second power supply (3) to the second switch (212) and the first switch (211) is greater than a predetermined value, the control unit (220) sets the second switch (212) to an off state; and

[0103] When the voltage of the second power supply system (201B) is lower than a predetermined value or the current value of the current flowing from the first power supply (2) to the first switch (211) and the second switch (212) is greater than a predetermined value, the control unit (220) sets the first switch (211) to an off state.

[0104] [5] According to the power supply control system described in [4] above,

[0105] When the output voltage of the power supply unit (4) is higher than a predetermined value, the control unit (220) sets the third switch (213) to an off state.

[0106] [6] According to the power supply control system described in [1] above,

[0107] The power supply unit (4) includes a power output unit (5) and a voltage conversion unit (6), and the voltage conversion unit (6) includes a unit for reducing the voltage of the power output from the power output unit (5) to output the reduced voltage power to the first switch (211) and the second switch (212) and cutting off the current flowing from one side of the first switch (211) and the other side of the second switch (212);

[0108] wherein, in the off state of the first switch (211), the first switch (211) cuts off the current flowing from one side of the power supply unit (4) to one side of the first power supply system (201A); and

[0109] In the off state of the second switch (212), the second switch (212) cuts off the current flowing from one side of the power supply unit (4) to one side of the second power supply system (201B),

[0110] The power control system also includes:

[0111] The housing is configured to accommodate a voltage conversion unit (6), a first switch (211), a second switch (212), and a wiring (H8) connecting the voltage conversion unit (6), the first switch (211), and the second switch (212).

[0112] [7] The power supply control system according to [6] further comprises:

[0113] A control unit (220) configured to control the first switch (211) and the second switch (212),

[0114] wherein when the voltage of the first power supply system (201A) is lower than a predetermined value or the current value of the current flowing from the second power supply (3) to the second switch (212) and the first switch (211) is greater than a predetermined value, the control unit (220) sets the first switch (211) to an off state; and

[0115] When the voltage of the second power supply system (201B) is lower than a predetermined value or the current value of the current flowing from the first power supply (2) to the first switch (211) and the second switch (212) is greater than a predetermined value, the control unit (220) sets the second switch (212) to an off state.

Claims

1. A power supply control system configured to control a redundant power supply system, the redundant power supply system comprising a first power supply system and a second power supply system connected in parallel to a power supply unit, the first power supply system comprising a first power supply and a first system supplied with power from the first power supply, the second power supply system comprising a second power supply and a second system supplied with power from the second power supply, the power supply control system comprising: a first switch, which is a MOSFET provided between the power supply unit and the first power supply; a second switch, which is a MOSFET provided between the power supply unit and the second power supply; a wiring configured to supply dark current flowing from the first power source to the second system; a normally open first relay, which is provided on the wiring; a normally closed second relay, disposed between the second power supply and the second switch; a third switch, which is a MOSFET, provided between the first switch and the power supply unit and between the second switch and the power supply unit, the third switch being configured to cut off a current flowing from one side of the power supply unit to one side of the first power supply system and one side of the second power supply system when the third switch is in an off state; wherein, in an off state of the first switch, the first switch cuts off current flowing from one side of the first power supply system to one side of the power supply unit; and In the off state of the second switch, the second switch cuts off the current flowing from one side of the second power supply system to one side of the power supply unit.

2. The power supply control system according to claim 1, in, The first switch, the second switch, and the third switch are N-channel MOSFETs; and The source of the first switch, the source of the second switch, and the source of the third switch are connected to each other, the drain of the first switch is connected to the first power supply and the first system, the drain of the second switch is connected to the second power supply and the second system, and the drain of the third switch is connected to the power supply unit.

3. The power control system according to claim 1 or 2, further comprising: a control unit configured to control the first switch and the second switch, wherein, when the voltage of the first power supply system is lower than a predetermined value or the current value of the current flowing from the second power supply to the second switch and the first switch is greater than a predetermined value, the control unit sets the second switch to an off state; and When the voltage of the second power supply system is lower than a predetermined value or the current value of the current flowing from the first power supply to the first switch and the second switch is greater than a predetermined value, the control unit sets the first switch to the off state.

4. The power supply control system according to claim 3, in, When the output voltage of the power supply unit is higher than a predetermined value, the control unit sets the third switch to an off state.

5. The power supply control system according to claim 1, in, The power supply unit includes a power output unit and a voltage conversion unit, the voltage conversion unit including a unit that reduces the voltage of the power output from the power output unit to output the reduced voltage power to the first switch and the second switch, and cuts off the current flowing from one side of the first switch and one side of the second switch; wherein, in an off state of the first switch, the first switch cuts off current flowing from one side of the power supply unit to one side of the first power supply system; and In the off state of the second switch, the second switch cuts off the current flowing from one side of the power supply unit to one side of the second power supply system. The power control system further includes: A housing is configured to accommodate the voltage conversion unit, the first switch, the second switch, and wiring connecting the voltage conversion unit, the first switch, and the second switch.

6. The power control system according to claim 5, further comprising: a control unit configured to control the first switch and the second switch, wherein, when the voltage of the first power supply system is lower than a predetermined value or the current value of the current flowing from the second power supply to the second switch and the first switch is greater than a predetermined value, the control unit sets the first switch to an off state; and When the voltage of the second power supply system is lower than a predetermined value or the current value of the current flowing from the first power supply to the first switch and the second switch is greater than a predetermined value, the control unit sets the second switch to the off state.

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