In-vehicle backup control device

Abstract

The present invention makes it possible to use, during backup operation, both an operation that supplies power to a common load from a first power storage unit and an operation that supplies power to the common load from a second power storage unit.　In at least a prescribed state in which supply of power from a power supply unit (90) to loads (91–95) has been cut off or reduced, an onboard backup control device (1) performs a backup operation that supplies power to the loads (91–95) on the basis of power from a first power storage unit (71) and a second power storage unit (72). The backup control device (1) has: a supply circuit (30) that supplies power to a load (93) from the first power storage unit (71) and the second power storage unit (72); and a first control unit (41) and a second control unit (42) that control, at the supply circuit (30), an operation that supplies power to the load (93) from the first power storage unit (71) and an operation that supplies power to the load (93) from the second power storage unit (72).

Description

Technical Field

[0001] The present disclosure relates to an in-vehicle backup control device.

Background Art

[0002] Patent Document 1 discloses a power storage device that supplies power from a power storage unit to a load when the voltage of the main power supply drops. The control circuit of this power storage device controls a charging circuit to charge the power storage unit when the main power supply is normal. Then, when the voltage of the main power supply drops (for example, when starting the engine after the end of idling stop), this control circuit turns on a switch arranged between the power storage unit and the load to supply power to the load. Further, Patent Document 1 describes that this power storage device can also be applied to a power backup system during main power supply abnormality.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The power storage device of Patent Document 1 is configured to supply power to a load to be backed up from one power storage unit. However, with such a configuration, there is only one power source for the load during backup, and the power supply method is limited.

[0005] An object of the present disclosure is to be able to use in combination an operation of supplying power from a first power storage unit to a common load and an operation of supplying power from a second power storage unit during a backup operation.

Means for Solving the Problems

[0006] An in-vehicle backup control device which is one of the present disclosures is An in-vehicle backup control device used in an in-vehicle power supply system including a power supply unit and a power storage unit, which performs a backup operation of supplying power to a load based on the power from the power storage unit when the supply of power from the power supply unit to the load is interrupted or reduced, wherein the power storage unit includes a first power storage unit and a second power storage unit, the load includes a predetermined common load, a supply circuit for supplying power from the first power storage unit and the second power storage unit to the common load, and a control unit for controlling an operation of supplying power from the first power storage unit to the common load and an operation of supplying power from the second power storage unit to the common load in the supply circuit. It has.

Effect of the Invention

[0007] The technology according to the present disclosure can use, in combination, an operation of supplying power from the first power storage unit and an operation of supplying power from the second power storage unit to a common load during a backup operation.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present disclosure will be listed and exemplified. Note that the features [1] to [5] exemplified below may be combined in any manner without contradiction.

[0010] [1] An in-vehicle backup control device used in an in-vehicle power supply system including a power supply unit and a power storage unit, which performs a backup operation of supplying power to a load based on the power from the power storage unit when a predetermined state occurs in which the supply of power from the power supply unit to the load is interrupted or reduced, The power storage unit includes a first power storage unit and a second power storage unit, The load includes a predetermined common load, A supply circuit that supplies power from the first power storage unit and the second power storage unit to the common load, A control unit that controls an operation of supplying power from the first power storage unit to the common load and an operation of supplying power from the second power storage unit to the common load in the supply circuit, An in-vehicle backup control device having the above.

[0011] The above in-vehicle backup control device of [1] can perform a backup operation using the power storage unit in a predetermined state in which the supply of power from the power supply unit is interrupted or reduced. In this backup control device, power can be supplied from the first power storage unit and the second power storage unit to a predetermined common load. Therefore, during the backup operation, the backup control device can use both an operation of supplying power from the first power storage unit and an operation of supplying power from the second power storage unit for the common load.

[0012] [2] The in-vehicle backup control device according to [1], having the following features. The in-vehicle backup control device further includes the first power storage unit and the second power storage unit described above.

[0013] The above in-vehicle backup control device of [2] can complete the backup operation within the device by having the first power storage unit and the second power storage unit.

[0014] 〔3〕The in-vehicle backup control device according to 〔1〕 or 〔2〕 has the following features. The supply circuit includes a first supply circuit and a second supply circuit. The first supply circuit outputs the power based on the first power storage unit toward the second supply circuit. The second supply circuit switches between a state of supplying the power based on the input from the first supply circuit to the common load and a state of supplying the power based on the second power storage unit to the common load.

[0015] In the in-vehicle backup control device of 〔3〕 above, it is possible to switch between a state of supplying power from the first power storage unit and a state of supplying power from the second power storage unit, and the power supply source can be selected from among the first power storage unit and the second power storage unit. Moreover, the second supply circuit has a function of supplying power to the common load from the second power storage unit and a function of switching between a state of supplying power from the first power storage unit and a state of supplying power from the second power storage unit. Therefore, compared with the case of providing a configuration having a function of separately switching between a state of supplying power from the first power storage unit and a state of supplying power from the second power storage unit, the configuration of the in-vehicle backup control device can be simplified.

[0016] 〔4〕The in-vehicle backup control device according to 〔3〕 has the following features. The supply circuit includes a first supply circuit and a second supply circuit. The second supply circuit outputs the power based on the second power storage unit toward the first supply circuit. The first supply circuit switches between a state of supplying the power based on the input from the second supply circuit to the common load and a state of supplying the power based on the first power storage unit to the common load.

[0017] In the in-vehicle backup control device of 〔4〕 above, the function of switching between a state of supplying power from the first power storage unit and a state of supplying power from the second power storage unit can also be provided in the first supply circuit.

[0018] In the in-vehicle backup control device according to [5], [1] or [2], it has the following characteristics. The supply circuit includes a first supply circuit, a second supply circuit, and a switching unit. The first supply circuit outputs electric power based on the first power storage unit. The second supply circuit outputs electric power based on the second power storage unit. The switching unit switches between a state in which electric power based on the output from the first supply circuit is supplied to the common load and a state in which electric power based on the output from the second supply circuit is supplied to the common load.

[0019] The in-vehicle backup control device of [5] above can switch between a state of supplying electric power from the first power storage unit and a state of supplying electric power from the second power storage unit, and can select the power supply source from among the first power storage unit and the second power storage unit. Moreover, by providing the switching unit separately from the first supply circuit and the second supply circuit, the configurations of the first supply circuit and the second supply circuit can be simplified.

[0020] <First Embodiment> [Configuration of In-Vehicle Power System] The in-vehicle power system 100 shown in FIG. 1 includes a power supply unit 90, loads 91, 92, 93, 94, 95, and an in-vehicle backup control device 1. The in-vehicle backup control device 1 is also referred to as the backup control device 1.

[0021] The power supply unit 90 functions as a main power supply that continuously supplies electric power when the vehicle on which the in-vehicle power system 100 is mounted starts. The power supply unit 90 is a DC power supply that generates a DC voltage. The power supply unit 90 is composed of a battery such as a lead battery, for example. The terminal on the high potential side of the power supply unit 90 is electrically connected to the power path 80, and the terminal on the low potential side of the power supply unit 90 is electrically connected to the ground. The power supply unit 90 applies a predetermined voltage to the power path 80. In this specification, the voltage is a voltage with respect to the ground unless otherwise specified.

[0022] The power supply unit 90 is electrically connected to loads 91, 92, 93, 94, 95 via the power path 80. Electric power from the power supply unit 90 is supplied to the loads 91, 92, 93, 94, 95 via the power path 80. In the example of FIG. 1, the power path 80 includes a power path 81A which is a conductive path directly connected to the power supply unit 90, a power path 81B connected to the load 91, a power path 81C which is a conductive path connected to the load 92, a power path 81D which is a conductive path connected to the load 93, a power path 81E which is a conductive path connected to the load 94, and a power path 81F which is a conductive path connected to the load 95. The power paths 81A, 81B, 81C, 81D, 81E, 81F are electrically connected to each other. In a state where electric power is supplied from the power supply unit 90 to the loads 91, 92, 93, 94, 95, the power paths 81A, 81B, 81C, 81D, 81E, 81F are at the same potential. Relays, fuses, etc. (not shown) are provided in the power path 80, and these elements have a function of cutting off the conduction of the power path 80.

[0023] The loads 91, 92, 93, 94, 95 are in-vehicle electrical devices. The loads 91, 92, 93, 94, 95 are loads for which power supply is desired in an abnormal state (failure state) where power supply from the power supply unit 90 has stopped. The loads 91, 92, 93, 94, 95 may be actuators such as motors, for example. Alternatively, they may be ECUs and actuators in an electric parking brake system, ECUs and actuators in a shift-by-wire control system, etc. Alternatively, they may be other in-vehicle electrical devices.

[0024] The load 93 corresponds to an example of the "predetermined common load" of the present disclosure. The load 93 can be supplied with power from the first power storage unit 71 via the first supply circuit 31 described later, and can be supplied with power from the second power storage unit 72 via the second supply circuit 32 described later.

[0025] The backup control device 1 includes a power supply circuit 30, a first control unit 41, a second control unit 42, a first detection unit 51, a second detection unit 52, a first power storage unit 71, and a second power storage unit 72. The power supply circuit 30 includes a first power supply circuit 31 and a second power supply circuit 32. The first control unit 41 and the second control unit 42 correspond to an example of the "control unit" of the present disclosure. The first power storage unit 71 and the second power storage unit 72 correspond to an example of the "power storage unit" of the present disclosure. The backup control device 1 is a device capable of performing a backup operation of supplying power to loads 91, 92, 93, 94, 95 based on the power of the first power storage unit 71 and the second power storage unit 72 when the power supply from the power supply unit 90 to the loads 91, 92, 93, 94, 95 is interrupted or reduced in a predetermined state (abnormal state).

[0026] The backup control device 1 has a first power storage unit 101 and a second power storage unit 102. The first power storage unit 101 includes the first power storage unit 71, the first control unit 41 (described later), the first power supply circuit 31, and the first detection unit 51. The second power storage unit 102 includes the second power storage unit 72, the second control unit 42 (described later), the second power supply circuit 32, and the second detection unit 52.

[0027] The first power storage unit 71 and the second power storage unit 72 function as auxiliary power supplies. The first power storage unit 71 and the second power storage unit 72 are DC power supplies that output a DC voltage, for example, electric double layer capacitors. The first power storage unit 71 is electrically connected to the first power supply circuit 31 (described later) via a conductive path 15, and charging and discharging are performed via the first power supply circuit 31. The charging voltage (output voltage) of the first power storage unit 71 is the voltage applied to the conductive path 15. The high-potential side terminal of the first power storage unit 71 is electrically connected to the conductive path 15 and has the same potential as the conductive path 15. The low-potential side terminal of the first power storage unit 71 is electrically connected to the ground and has the same potential as the ground.

[0028] The second power storage unit 72 is electrically connected to a second supply circuit 32, which will be described later, via a conductive path 25, and is charged and discharged via the second supply circuit 32. The charging voltage (output voltage) of the second power storage unit 72 is the voltage applied to the conductive path 25. The terminal on the high potential side of the second power storage unit 72 is electrically connected to the conductive path 25 and has the same potential as the conductive path 25. The terminal on the low potential side of the second power storage unit 72 is electrically connected to the ground and has the same potential as the ground.

[0029] In the backup control device 1, in a stopped state where the start switch of the vehicle on which the in-vehicle power supply system 100 is mounted is in the off state, the charging voltages (output voltages) of the first power storage unit 71 and the second power storage unit 72 are held below the standby voltage. Then, when the start switch of the vehicle is switched to the on state, the backup control device 1 charges the first power storage unit 71 and the second power storage unit 72 so that the charging voltages thereof are equal to or higher than a target voltage greater than the standby voltage. When the start switch of the vehicle is in the on state and no fault state has occurred, the charging voltages of the first power storage unit 71 and the second power storage unit 72 are maintained at the target voltage. When the start switch of the vehicle is switched from the on state to the off state, the backup control device 1 discharges the first power storage unit 71 and the second power storage unit 72 until the charging voltages thereof become equal to or lower than the standby voltage.

[0030] The first supply circuit 31 functions to supply power from the first power storage unit 71 to the loads 91, 92, and the second supply circuit 32. The second supply circuit 32 functions to supply power to the loads 94, 95.

[0031] The first power supply circuit 31 outputs the power based on the first power storage unit 71 toward the second power supply circuit 32. The first power supply circuit 31 operates based on the control of the first control unit 41 described later. The first power supply circuit 31 is disposed between the conductive path 14 and the conductive paths 11, 12, and 13. The first power supply circuit 31 has a voltage conversion circuit such as a DC-DC converter, for example. The voltage conversion circuit performs a charging operation and a discharging operation on the first power storage unit 71. As the charging operation, the voltage conversion circuit performs a voltage conversion operation of boosting or bucking the voltage applied to the conductive path 14 and applying it to the conductive path 15. As the discharging operation, the voltage conversion circuit performs a voltage conversion operation of boosting or bucking the voltage applied to the conductive path 15 and applying it to the conductive paths 11 or the like.

[0032] The second power supply circuit 32 switches between a state of supplying the power based on the input from the first power supply circuit 31 to the load 93 and a state of supplying the power based on the second power storage unit 72 to the load 93. The second power supply circuit 32 operates based on the control of the second control unit 42 described later. The second power supply circuit 32 is disposed between the conductive path 24 and the conductive paths 21, 22, and 23. The second power supply circuit 32 has a voltage conversion circuit such as a DC-DC converter, for example. The voltage conversion circuit performs a charging operation and a discharging operation on the second power storage unit 72. As the charging operation, the voltage conversion circuit performs a voltage conversion operation of boosting or bucking the voltage applied to the conductive path 24 and applying it to the conductive path 25. When supplying the power based on the second power storage unit 72 to the load 93, as the discharging operation, the voltage conversion circuit performs a voltage conversion operation of boosting or bucking the voltage applied to the conductive path 25 and applying it to the conductive paths 21 or the like.

[0033] The first control unit 41 controls the operation of supplying power from the first power storage unit 71 to the loads 91, 92, and the second supply circuit 32. The first control unit 41 is an information processing device having an information processing function, an arithmetic function, a control function, and the like. The first control unit 41 is mainly configured by, for example, a microcomputer, and has an arithmetic device such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), an A / D converter, and the like. The first control unit 41 has a function of controlling the first supply circuit 31.

[0034] The second control unit 42 controls the operation of supplying power from the second power storage unit 72 to the loads 93, 94, 95. The second control unit 42 is an information processing device having an information processing function, an arithmetic function, a control function, and the like. The second control unit 42 is mainly configured by, for example, a microcomputer, and has an arithmetic device such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), an A / D converter, and the like. The second control unit 42 has a function of controlling the second supply circuit 32.

[0035] The first detection unit 51 is configured as, for example, a voltage detection circuit. The first detection unit 51 detects the voltage of the conductive path 14. The conductive path 14 is electrically connected to the power path 80 and has the same potential as the power path 80. Therefore, the first detection unit 51 can detect the voltage of the power path 80.

[0036] The conductive path 11 is the conductive path between the first supply circuit 31 and the load 91. The conductive path 12 is the conductive path between the first supply circuit 31 and the load 92. The conductive path 13 is the conductive path between the first supply circuit 31 and the second supply circuit 32.

[0037] The second detection unit 52 is configured as, for example, a voltage detection circuit. The second detection unit 52 detects the voltage of the conductive path 24. The conductive path 24 is electrically connected to the power path 80 and has the same potential as the power path 80. Therefore, the second detection unit 52 can detect the voltage of the power path 80.

[0038] The conductive path 21 is a conductive path between the second supply circuit 32 and the load 93. The conductive path 22 is a conductive path between the second supply circuit 32 and the load 94. The conductive path 23 is a conductive path between the second supply circuit 32 and the load 95.

[0039] 〔Operation of Backup Control Device〕 FIG. 2 shows an example of backup control performed by the backup control device 1 (specifically, the first control unit 41 and the second control unit 42). The first control unit 41 and the second control unit 42 start the backup control shown in FIG. 2 when a predetermined start condition is satisfied. The condition for starting the backup control shown in FIG. 2 may be, for example, that the start switch of the vehicle equipped with the in-vehicle power supply system 100 is switched from the off state to the on state, or may be other conditions. In the representative example described below, when the start switch of the vehicle is switched from the off state to the on state, a start signal indicating that the start switch has been switched to the on state is given from an external device (for example, an external ECU (Electronic Control Unit)) to the first control unit 41 and the second control unit 42. The first control unit 41 and the second control unit 42 start the backup control shown in FIG. 2 when receiving such a start signal.

[0040] When the first control unit 41 and the second control unit 42 start the backup control shown in FIG. 2, in step S11, they perform charging so that the charging voltages of the first power storage unit 71 and the second power storage unit 72 are equal to or higher than a target voltage that is higher than the standby voltage. The first control unit 41 and the second control unit 42 maintain the charging voltages of the first power storage unit 71 and the second power storage unit 72 at the above target voltage.

[0041] The first control unit 41 and the second control unit 42 determine whether the output voltage of the power supply unit 90 (main power supply) has decreased (is in a predetermined decreased state) in step S12. For example, the first control unit 41 determines whether the voltage of the conductive path 14 is less than the threshold value (is in a predetermined decreased state) based on the voltage detected by the first detection unit 51. This threshold value is a value significantly smaller than the output voltage applied to the power path 80 when the power supply unit 90 is normal, and is a value greater than 0. Note that the second control unit 42 may determine whether the voltage of the conductive path 24 is less than the threshold value (is in a predetermined decreased state) based on the voltage detected by the second detection unit 52. When the first control unit 41 determines in step S12 that the voltage of the conductive path 14 is less than the threshold value (Yes in step S12), the process proceeds to step S13. In this representative example, the case where the voltage of the conductive path 14 is less than the threshold value, that is, the case where the voltage of the power path 80 is less than the threshold value corresponds to an example of the "predetermined state" of the present disclosure. When the first control unit 41 determines in step S12 that the voltage of the conductive path 14 is greater than or equal to the threshold value (No in step S12), the process of step S11 is performed again.

[0042] For example, in an abnormal state where a ground fault or disconnection occurs in the power path 80 and the power supply from the power supply unit 90 to the conductive paths 14 and 24 and the power supply to the power paths 81B, 81C, 81D, 81E, and 81F are interrupted, the voltages of the conductive paths 14 and 24 become about 0V. In such a case, in the backup control device 1, the first control unit 41 and the second control unit 42 perform a backup operation of supplying power to the plurality of loads 91, 92, 93, 94, and 95 based on the power from the first power storage unit 71 and the second power storage unit 72. The second control unit 42 performs the processes after step S13 for the loads 93, 94, and 95. Note that hereinafter, the description of the backup operation for the loads 91 and 92 by the first control unit 41 is omitted, and an example in which the second control unit 42 supplies power to the loads 93, 94, and 95 will be described.

[0043] If the second control unit 42 determines in step S12 that the voltage of the conductive path 14 is less than the threshold value (Yes in step S12), in step S13, it starts supplying power to the loads 93, 94, and 95. The second control unit 42 causes the second supply circuit 32 to supply power to the conductive paths 21, 22, and 23.

[0044] In the next step S14, the second control unit 42 controls the power supply to the load 93. The second control unit 42 switches the second supply circuit 32 between a state in which the power based on the input from the first supply circuit 31 is supplied to the load 93 and a state in which the power based on the second power storage unit 72 is supplied to the load 93. When the second control unit 42 supplies the power based on the input from the first supply circuit 31 to the load 93, the second control unit 42 operates the second supply circuit 32 so that the voltage applied to the conductive path 13 (voltage of magnitude V1) is applied to the conductive path 21. The voltage V1 is a voltage obtained by stepping up or stepping down the output voltage from the first power storage unit 71 by the voltage conversion circuit of the first supply circuit 31. When the second control unit 42 supplies the power based on the second power storage unit 72 to the load 93, the second control unit 42 operates so that the voltage based on the output voltage of the second power storage unit 72 (voltage of magnitude V2) is applied to the conductive path 21. Voltage V2 is a voltage obtained by stepping up or stepping down the output voltage from second power storage unit 72 using a voltage conversion circuit in second supply circuit 32. Voltages V1 and V2 may be the same magnitude (slightly different values).

[0045] In the subsequent step S15, the first control unit 41 and the second control unit 42 determine whether the vehicle equipped with the in-vehicle power supply system 100 is in a stopped state. The first control unit 41 and the second control unit 42 determine whether the start switch of the vehicle equipped with the in-vehicle power supply system 100 has been switched from the on state to the off state. For example, when the start switch of the vehicle changes from the on state to the off state, a start signal indicating that the start switch has been switched to the off state is given from an external device (for example, an external ECU (Electronic Control Unit)) to the first control unit 41 and the second control unit 42. When the first control unit 41 and the second control unit 42 receive such a start signal, they determine that the vehicle is in a stopped state. If the first control unit 41 and the second control unit 42 determine in step S15 that the vehicle is not in a stopped state (is in a starting state) (No in step S15), they perform the process of step S14 again. If the first control unit 41 and the second control unit 42 determine in step S15 that the vehicle is in a stopped state (Yes in step S15), they end the backup control shown in FIG. 2.

[0046] The following description relates to an example of the effects of this configuration. The backup control device 1 can perform a backup operation using the first power storage unit 71 and the second power storage unit 72 in a predetermined state where the power supply from the power supply unit 90 is interrupted or reduced. In this backup control device 1, power can be supplied to the load 93 from the first power storage unit 71 and the second power storage unit 72. Therefore, during the backup operation, the backup control device 1 can use a combination of an operation of supplying power from the first power storage unit 71 and an operation of supplying power from the second power storage unit 72 to the load 93.

[0047] Furthermore, the backup control device 1 includes the first power storage unit 71 and the second power storage unit 72. Therefore, by having the first power storage unit 71 and the second power storage unit 72, the backup control device 1 can complete the backup operation within the device.

[0048] Furthermore, the backup control device 1 can switch between a state of supplying power from the first power storage unit 71 and a state of supplying power from the second power storage unit 72, and can select the power supply source from among the first power storage unit 71 and the second power storage unit 72. Moreover, the second supply circuit 32 has a function of supplying power to the load 93 from the second power storage unit 72 and a function of switching between a state of supplying power from the first power storage unit 71 and a state of supplying power from the second power storage unit 72. Therefore, compared with the case of providing a configuration having a function of separately switching between a state of supplying power from the first power storage unit 71 and a state of supplying power from the second power storage unit 72, the configuration of the backup control device 1 can be simplified.

[0049] <Second Embodiment> The in-vehicle power supply system 200 of the second embodiment has a switching unit 33 and is different from the first embodiment in that the switching unit 33 switches the power supplied to the load 93, and is common in other respects. Note that the same reference numerals are given to the same configurations as those in the first embodiment, and detailed descriptions thereof are omitted.

[0050] As shown in FIG. 3, the in-vehicle power supply system 200 includes an in-vehicle backup control device 1 (also referred to as the backup control device 1). The supply circuit 230 of the backup control device 1 includes a first supply circuit 31, a second supply circuit 32, and a switching unit 233. The first supply circuit 31 functions to supply power to the switching unit 233. The first supply circuit 31 outputs the power based on the first power storage unit 71 toward the switching unit 233 via the conductive path 213. The conductive path 213 is a conductive path between the first supply circuit 31 and the switching unit 233.

[0051] The second supply circuit 32 functions to supply power to the switching unit 233. The second supply circuit 32 outputs the power based on the second power storage unit 72 toward the switching unit 233 via the conductive path 221. The conductive path 221 is a conductive path between the second supply circuit 32 and the switching unit 233. The conductive path 234 is a conductive path between the switching unit 233 and the load 93.

[0052] The switching unit 233 switches between a state of supplying power based on the output from the first power supply circuit 31 to the load 93 and a state of supplying power based on the output from the second power supply circuit 32 to the load 93. The switching unit 233 has, for example, a switch or the like. The switching unit 233 operates under the control of, for example, the first control unit 41 and the second control unit 42.

[0053] 〔Operation of Backup Control Device〕 The backup control performed by the backup control device 1 (specifically, the first control unit 41 and the second control unit 42) of the second embodiment differs from that of the first embodiment only in step S14.

[0054] In step S14, the first control unit 41 and the second control unit 42 perform power supply control for the load 93. The first control unit 41 and the second control unit 42 cause the switching unit 233 to switch between a state of supplying power based on the input from the first power supply circuit 31 to the load 93 and a state of supplying power based on the second power storage unit 72 to the load 93. When the switching unit 233 supplies power based on the input from the first power supply circuit 31 to the load 93, it operates so that the voltage applied to the conductive path 213 (voltage of magnitude V21) is applied to the conductive path 234. The voltage V21 is a voltage obtained by boosting or bucking the output voltage from the first power storage unit 71 by the voltage conversion circuit of the first power supply circuit 31. When the first control unit 41 and the second control unit 42 supply power based on the second power storage unit 72 to the load 93, they operate so that the voltage based on the output voltage of the second power storage unit 72 (voltage of magnitude V22) is applied to the conductive path 234. The voltage V22 is a voltage obtained by boosting or bucking the output voltage from the second power storage unit 72 by the voltage conversion circuit of the second power supply circuit 32. The voltage V21 and the voltage V22 may have the same magnitude (slightly different values).

[0055] The following description relates to an example of the effect of this configuration. In the backup control device 1, the supply circuit 230 includes a first supply circuit 31, a second supply circuit 32, and a switching unit 233. The switching unit 233 switches between a state of supplying power based on the output from the first supply circuit 31 to the load 93 and a state of supplying power based on the output from the second supply circuit 32 to the load 93. Therefore, the backup control device 1 can switch between a state of supplying power from the first power storage unit 71 and a state of supplying power from the second power storage unit 72, and can select the power supply source from among the first power storage unit 71 and the second power storage unit 72. Moreover, since the switching unit 233 is provided separately from the first supply circuit 31 and the second supply circuit 32, the configurations of the first supply circuit 31 and the second supply circuit 32 can be simplified.

[0056] <Third Embodiment> The in-vehicle power supply system 300 of the third embodiment is different from the first embodiment in that the first power storage unit 101 has a function of switching the power source for the load 93, and is the same in other respects. Note that the same reference numerals are assigned to the same configurations as those in the first embodiment, and detailed descriptions thereof are omitted.

[0057] As shown in FIG. 4, the in-vehicle power supply system 300 has a conductive path 16. The conductive path 16 is a conductive path between the first supply circuit 31 and the load 93. The first supply circuit 31 switches between a state of supplying power based on the input from the second supply circuit 32 to the load 93 and a state of supplying power based on the first power storage unit 71 to the load 93.

[0058] The backup control by the backup control device 1 of the third embodiment is mainly the same as that of the first embodiment (see FIG. 2), and the control described below is different. The backup control device 1 of the third embodiment has a function of switching the power source (the first power storage unit 71 and the second power storage unit 72) by the first supply circuit 31.

[0059] In step S14 of the backup control (see FIG. 2), the first supply circuit 31 performs switching control of the power source. The 1 Control unit 4 1 is the 1 Supply circuit 3 1The first control unit 41 switches between a state in which power based on an input from the second supply circuit 32 is supplied to the load 93 and a state in which power based on the first power storage unit 71 is supplied to the load 93. When power based on an input from the second supply circuit 32 is supplied to the load 93, the first control unit 41 operates the first supply circuit 31 so that the voltage applied to the conductive path 13 (a voltage having a magnitude V2) is applied to the conductive path 16. The voltage V2 is a voltage obtained by stepping up or stepping down the output voltage from the second power storage unit 72 using the voltage conversion circuit of the second supply circuit 32. When power based on the first power storage unit 71 is supplied to the load 93, the first control unit 41 operates so that a voltage based on the output voltage of the first power storage unit 71 (a voltage having a magnitude V1) is applied to the conductive path 16. The voltage V1 is a voltage obtained by stepping up or stepping down the output voltage from the first power storage unit 71 using the voltage conversion circuit of the first supply circuit 31. Voltage V1 and voltage V2 may be the same magnitude (slightly different values).

[0060] In the backup control device 1 of the third embodiment, the first supply circuit 31 can be provided with a function of switching between a state in which power is supplied from the first power storage unit 71 and a state in which power is supplied from the second power storage unit 72.

[0061] <Other embodiments> The present disclosure is not limited to the embodiments described above and in the drawings. For example, the features of the above or later described embodiments can be combined in any combination within a range that does not contradict. In addition, any feature of the above or later described embodiments can be omitted unless it is clearly stated as essential. Furthermore, the above-mentioned embodiment may be modified as follows.

[0062] In the above embodiment, in the backup control of the backup control device 1, in step S12, as a predetermined state, a state where the voltage of the conductive path 14 is less than the threshold value was exemplified, but other states may also be used. For example, the predetermined state may be a state in which a request for a backup operation is made from the load (specifically, a state in which at least one of the first control unit 41 and the second control unit 42 receives a signal requesting a backup operation from the load).

[0063] In the above first to third embodiments, the loads 91, 92, 93, 94, 95 were configured to be able to be supplied with power from the power supply unit 90 via the power paths 81B, 81C, 81D, 81E, 81F, respectively, but a configuration without the power paths 81B, 81C, 81D, 81E, 81F may also be used. In this case, power during normal times (when the power supply unit 90 is normal) is supplied to the loads 91, 92, 93, 94, 95 directly by the backup power supplies (the first power storage unit 71 and the second power storage unit 72).

[0064] In the above second embodiment, the first power storage unit 101 and the second power storage unit can supply power to the common load (load 93) by a backup operation regardless of the presence or absence of a power supply path to the common load (load 93). Similarly, in the above third embodiment, the first power storage unit 101 and the second power storage unit can supply power to the common load (load 93) by a backup operation independently even without an input from the other unit.

[0065] In the above third embodiment, a conductive path connecting the second supply circuit 32 and the load 93 may be provided, and in addition to the first supply circuit 31, the second supply circuit 32 may also have a function of switching the power sources (the first power storage unit 71 and the second power storage unit 72).

[0066] In the above first embodiment, the start switch of the vehicle is described, but the start switch may be an ignition switch. Alternatively, in an electric vehicle or the like, it may be a power switch for guiding the EV system.

[0067] In the above-described first embodiment, the power supply unit is a lead battery, but it is not limited to a lead battery. The power supply unit may be, for example, another type of battery such as a lithium-ion battery, or a power supply such as an alternator or a converter.

[0068] In the above-described first embodiment, the power storage unit is an electric double layer capacitor, but the power storage unit is not limited to an electric double layer capacitor. The power storage unit may be another type of power storage unit such as a lithium-ion capacitor or a lithium-ion battery.

[0069] In the above-described first embodiment, when the power supply from the power supply unit is interrupted, the backup control device performs a backup operation. However, the backup control device may perform a backup operation so as to supply power from the power storage unit in a predetermined state where the power supply is not completely interrupted.

[0070] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments disclosed this time, and is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims.

Explanation of Reference Numerals

[0071] 1: Backup control device 11, 12, 13, 14, 15: Conductive path 21, 22, 23, 24, 25: Conductive path 30: Supply circuit 31: First supply circuit 32: Second supply circuit 33: Switching unit 41: First control unit (control unit) 42: Second control unit (control unit) 51: First detection unit 52: Second detection unit 71: First power storage unit (power storage unit) 72: Second power storage unit (power storage unit) 80: Power path 81A, 81B, 81C, 81D, 81E, 81F: Power circuit 90: Power supply unit 91, 92, 94, 95: Load 93: Load (common load) 100, 200, 300: In-vehicle power supply system 101: First power storage unit 102: Second power storage unit 213, 221, 234: Conductive path 230: Supply circuit 233: Switching unit

Claims

1. An in-vehicle backup control device used in an in-vehicle power supply system including a power supply unit and a power storage unit, and performing a backup operation of supplying power to a load based on the power from the power storage unit when the power supply from the power supply unit to the load is interrupted or reduced in a predetermined state, wherein the power storage unit includes a first power storage unit and a second power storage unit, the load includes a predetermined common load, a supply circuit for supplying power from the first power storage unit and the second power storage unit to the common load, and a control unit for controlling an operation of supplying power from the first power storage unit to the common load and an operation of supplying power from the second power storage unit to the common load in the supply circuit, characterized by having, the supply circuit having a first supply circuit and a second supply circuit, the first supply circuit outputting power based on the first power storage unit toward the second supply circuit, the second supply circuit switching between a state of supplying power based on the input from the first supply circuit to the common load and a state of supplying power based on the second power storage unit to the common load, a first power storage unit and a second power storage unit, the first power storage unit including the first supply circuit and a first control unit for controlling the operation of the first supply circuit, the second power storage unit including the second supply circuit and a second control unit for controlling the operation of the second supply circuit, wherein the first supply circuit and the second supply circuit are in-vehicle backup control devices including a DC-DC converter.

2. The in-vehicle backup control device according to claim 1, further having the first power storage unit and the second power storage unit.

3. (Deleted)

4. The second supply circuit outputs power based on the second power storage unit toward the first supply circuit, and the first supply circuit switches between a state of supplying power based on the input from the second supply circuit to the common load and a state of supplying power based on the first power storage unit to the common load. The in-vehicle backup control device according to claim 1 or claim 2.

5. An in-vehicle backup control device used in an in-vehicle power supply system including a power supply unit and a power storage unit, and performing a backup operation of supplying power to a load based on the power from the power storage unit when the power supply from the power supply unit to the load is interrupted or reduced in a predetermined state, wherein the power storage unit includes a first power storage unit and a second power storage unit, the load includes a predetermined common load, A supply circuit that supplies power from the first power storage unit and the second power storage unit to the common load; A control unit that controls an operation of supplying power from the first power storage unit to the common load and an operation of supplying power from the second power storage unit to the common load in the supply circuit; It has, The supply circuit includes a first supply circuit, a second supply circuit, and a switching unit, The first supply circuit outputs power based on the first power storage unit, The second supply circuit outputs power based on the second power storage unit, The switching unit switches between a state of supplying power based on the output from the first supply circuit to the common load and a state of supplying power based on the output from the second supply circuit to the common load, It has a first power storage unit and a second power storage unit, The first power storage unit includes the first supply circuit and a first control unit that controls the operation of the first supply circuit, The second power storage unit includes the second supply circuit and a second control unit that controls the operation of the second supply circuit, The first supply circuit and the second supply circuit are in-vehicle backup control devices including a DC-DC converter.

6. The in-vehicle backup control device according to claim 5, further comprising the first power storage unit and the second power storage unit.

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