POWER SUPPLY CONTROL DEVICE AND STORAGE MEDIUM

Abstract

A power supply control device comprises: a first switch coupled between a main power supply and a load; a second switch coupled between an auxiliary power supply and the load; and a control unit configured to perform on / off control of the first and second switches. The control unit is configured to: turn off the first switch and turn on the second switch when an ignition switch is turned off; and turn off the second switch and then turn on the first switch when the ignition switch is turned on.

Description

TECHNICAL FIELD

[0001] The embodiments disclosed herein relate to a power supply control device and a storage medium storing a power supply control program. STATE OF THE ART

[0002] There exists a system including a load driven by supplying electric power during a period in which an ignition switch (hereinafter referred to as "IG") of a vehicle is turned off and a load driven by supplying electric power during a period in which the IG is turned on (for example, see Japanese Patent Application Laid-Open No. 2009-83527 (hereinafter referred to as Patent Literature 1)).

[0003] In such a system, if electric power is supplied from the main power supply to the load while the IG is off, the electric power from the main power supply may be insufficient when the IG is turned on and the electric power supply to each load starts.

[0004] Therefore, it is desirable to provide a sub-power supply for supplying electric power during the period when the IG is off and to supply electric power from the sub-power supply to the load during the period when the IG is off.

[0005] However, if the IU is turned on while the load is energized during the period in which the IU is off, a power surge may occur when the switches of the respective units are switched between on and off, resulting in switch failure.

[0006] An aspect of the embodiments has been made in view of the above, and an object thereof is to provide a power supply control device and a power supply control program capable of preventing a breaker from failing even if a surge power occurs when an IG is turned on and electric power supply from a main power supply to a load is started. SUMMARY

[0007] One aspect of this disclosure relates to a power supply control device comprising: a first switch coupled between a main power supply and a load; a second switch coupled between a sub-power supply and the load; and a controller configured to perform on / off control of the first switch and the second switch. The controller is configured to: turn off the first switch and turn on the second switch when an ignition switch is turned off; and turn off the second switch and then turn on the first switch when the ignition switch is turned on.

[0008] The power supply control device and the power supply control program according to one aspect of the embodiments have an effect of being able to prevent a switch from failing even if a surge power occurs when an IG is turned on and the electric power supply from a main power supply to a load is started. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Exemplary embodiments of this disclosure will be described in detail based on the following figures, wherein: Fig. 1 is a diagram illustrating a configuration example of a power supply control apparatus according to a first embodiment; Fig. 2 is a diagram illustrating an operation example of the power supply control device according to the first embodiment; Fig. 3 is a diagram illustrating an operation example of the power supply control device according to the first embodiment; Fig. 4 is a diagram illustrating an operation example of the power supply control device according to the first embodiment; Fig. 5 is a flowchart illustrating an example of a process executed by a controller of the power supply control apparatus according to the first embodiment; Fig. 6 is a flowchart illustrating an example of a process executed by the controller of the power supply control apparatus according to the first embodiment; Fig. 7 is a flowchart illustrating an example of processing executed by the controller of the power supply control apparatus according to the first embodiment; Fig. 8 is a flowchart illustrating an example of a process executed by the controller of the power supply control apparatus according to the first embodiment; Fig. 9 is a diagram illustrating a configuration example of a power supply control apparatus according to a second embodiment; Fig. 10 is a diagram illustrating an operation example of the power supply control device according to the second embodiment; Fig. 11 is a diagram illustrating an operation example of the power supply control device according to the second embodiment; Fig. 12 is a diagram illustrating an operation example of the power supply control device according to the second embodiment; Fig. 13 is a diagram illustrating an operation example of the power supply control device according to the second embodiment; and Fig. 14 is a flowchart illustrating an example of a process executed by a controller of the power supply control apparatus according to the second embodiment. DESCRIPTION OF THE EMBODIMENTS

[0010] Embodiments of a power supply control device and a power supply control method will be described in detail below with reference to the accompanying drawings. This disclosure is not limited to the following embodiments. The power supply control device according to the embodiments is a device that controls the supply of electric power to an electronic device (hereinafter referred to as a "load") mounted in a vehicle. [1. First Embodiment][1-1. Configuration Example of the Power Supply Control Device According to the First Embodiment]

[0011] Fig. 1 is a diagram illustrating a configuration example of a power supply control device 1 according to a first embodiment. As shown in Fig. 1, the power supply control device 1 is connected to a main power supply 10, a first load 101, a second load 102, an ignition switch (hereinafter referred to as “IG 103”) of a vehicle, and a notification device 104.

[0012] The main power supply 10 is, for example, a lead-acid battery mounted in the vehicle. The main power supply 10 may be a secondary battery other than the lead-acid battery. The first load 101 is a device that operates while the IG 103 is turned on, and may be any of various electronic devices related to vehicle driving or the like. The first load 101 includes, for example, an engine control device, a steering control device, a brake control device, an audio device, and a video display device.

[0013] The second load 102 is an electronic device capable of operating at all times (even when an accessory switch is turned on), that is, during the time when the IG 103 is turned off and during the time when the IG 103 is turned on. The second load 102 includes, for example, a tachograph, a security device, and an in-vehicle power outlet for supplying electrical power to an external device. The notification device 104 includes a display device that displays various notifications to the user, a sound playback device that plays notifications, and the like.

[0014] The power supply control device 1 includes a sub-power supply 20, a first system 110, a second system 120, switches 11 to 7 (numbered 11 to 17), and a controller 3. The sub-power supply 20 may be, for example, a lithium-ion battery, and the sub-power supply 20 may be a secondary battery other than the lithium-ion battery.

[0015] The auxiliary power supply 20 supplies electrical power to the second load 102 during the period in which the IG 103 is off. The auxiliary power supply 20 also acts as a backup power supply, supplying electrical power to the first load 101 and the second load 102 instead of the main power supply 10 when a power failure occurs in the main power supply 10.

[0016] The first system 110 is a power supply line through which the first load 101 and the second load 102 are supplied with electrical power from the main power supply 10. The second system 120 is a power supply line through which the first load 101 and the second load 102 are supplied with electrical power from the sub-power supply 20.

[0017] The first switch 11 is a switch that can connect and disconnect the main power supply 10 and the first system 110. The second switch 12 is a switch that can connect and disconnect the sub-power supply 20 and the second system 120.

[0018] The third switch 13 is a system-wide switch that can connect and disconnect the first system 110 and the second system 120. The third switch 13 can be a DC-DC converter (DC / DC) that compensates for a voltage difference between the first system 110 and the second system 120. If the third switch 13 is a DC / DC converter, the DC / DC connects the first system 110 and the second system 120 through one operation and disconnects the first system 110 and the second system 120 by stopping the operation.

[0019] The fourth switch 14 is a switch that can connect and disconnect the first system 110 and the first load 101. The fifth switch 15 is a switch that can connect and disconnect the second system 120 and the first load 101.

[0020] The sixth switch 16 is a switch that can connect and disconnect the first system 110 and the second load 102. The seventh switch 17 is a switch that can connect and disconnect the second system 120 and the second load 102.

[0021] Control unit 3 comprises a microcomputer with a central processing unit (CPU), a read-only memory (ROM), and a random access memory (RAM), as well as various circuits. Control unit 3 controls switches 1 through 7 (11 through 17) by executing a program stored in ROM and using RAM as a work area.

[0022] When a signal indicating that the IG 103 is turned on or a signal indicating that the IG 103 is turned off is received, the control unit 3 controls the switches one to seven 11 to 17 according to the received signal.

[0023] The control unit 3 monitors a failure of the first system 110 and the second system 120 based on the detection results of a voltage sensor (not illustrated) that detects a voltage of the first system 110 and a voltage sensor (not illustrated) that detects a voltage of the second system 120. When a failure occurs in one of the systems, the control unit 3 controls the first to seventh switches 11 to 17 to supply electric power to the first load 101 and the second load 102 via the other system.

[0024] A section or the entire control unit 3 can be implemented by hardware such as an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA). [1-2. Operation example of the power supply control device according to the first embodiment]

[0025] Next, an operation example of the power supply control device 1 according to the first embodiment will be described with reference to Fig. 2 to 4. Fig. 2 to 4 are diagrams illustrating an operation example of the power supply control device 1 according to the first embodiment.

[0026] When the vehicle is parked, ie when the IG 103 is switched off, as in Fig. 2, the power supply control device 1 turns off the first switch 11 and the third to sixth switches 13 to 16, turns on the second switch 12 and the seventh switch 17, and supplies the second load 102 with electric power from the auxiliary power supply 20. Accordingly, the power supply control device 1 can operate, for example, the safety device during parking.

[0027] Thereafter, when the IG 103 is turned on, the power supply control device 1 turns off the second switch 12, turns on the first switch 11 and the third to seventh switches 13 to 17, and supplies the first load 101 and the second load 102 with electric power from the main power supply 10.

[0028] However, if the power supply control device 1 turns on the first switch 11 in a state where the second switch 12 is turned on immediately after the IG 103 is turned on, and then turns off the second switch 12 in a state where a current flows therein, a surge current may occur and the second switch 12 may fail.

[0029] Therefore, when the turning on of the IG 103 is detected, the control unit 3 leaves the first switch 11 temporarily off and then turns the first switch 11 on to supply the first load 101 with electric power from the main power supply 10.

[0030] Here, the control unit 3, as for example in Fig. 3, turn off the seventh switch 17 in a state where the first switch 11 remains temporarily off, and then turn off the second switch 12 when it receives an IG-ON signal from the vehicle indicating that the IG 103 is on.

[0031] Accordingly, when the second switch 12 is turned off, no current flows through the second switch 12. Therefore, even when the second switch 12 is turned off, the control device 3 can prevent failure of the second switch 12 due to a current surge.

[0032] Then the control unit 3 switches, as in Fig. 4, the first switch 11 and the third to seventh switches 13 to 17 are turned on in a state where the second switch 12 is turned off, and supplies the first load 101 and the second load 102 with electric power from the main power supply 10. Accordingly, the power supply control device 1 can put the vehicle into a running state.

[0033] Here, the controller 3 turns off the seventh switch 17 before turning off the second switch 12, but this is only an example. When the power consumption of the second load 102 is less than the predetermined electric current, the probability of the second switch 12 failing due to a power surge is low, even if the power supply control device 1 turns off the second switch 12 while the seventh switch 17 remains on.

[0034] When the turn-on of the IG 103 is detected, the control unit 3 may prompt the user to stop the operation of the second load 102 if a second load 102 whose power consumption is equal to or greater than the predetermined electric current is present. For example, when the turn-on of the IG 103 is detected, the control unit 3 causes the notification device 104 to output a message such as "Please stop the external device" when the user plugs into the power outlet in the vehicle and uses the external device. Whether the power consumption of the external device is equal to or greater than the predetermined electric current can be detected by a current sensor or the like (not illustrated) that detects a current flowing through the output included in the second load 102.

[0035] Accordingly, in the power supply control device 1, when the user stops the operation of the second load 102 in response to the stop request, if the second switch 12 is turned off while the IG 103 is turned on, no current flows through the second switch 12, and thus failure of the second switch 12 due to a current surge can be prevented.

[0036] When the power consumption of the second load 102 drops below the predetermined electric current after the termination of operation is requested, the controller 3 may turn off the second switch 12 and then turn on the first switch 11. Accordingly, in the power supply control device 1, since the current flowing through the second switch 12 decreases at a time when the second switch 12 is turned off, even if the second switch 12 is turned off, failure of the second switch 12 due to a power surge can be prevented.

[0037] When a predetermined period of time has elapsed after the request to stop the operation, the controller 3 may turn off the second switch 12 and then turn on the first switch 11. Accordingly, if the user stops the operation of the second load 102 in response to the stop request during the predetermined period of time when the second switch 12 is turned off, the power supply control device 1 can prevent the failure of the second switch 12 due to the power surge and avoid a delay in starting a post-start operation.

[0038] When the turning on of the IG 103 is detected and a second load 102 whose power consumption is equal to or greater than the predetermined electric current is present, the control device 3 notifies the user that the second load 102 should be stopped, stops the operation of the second load 102, turns off the second switch 12 and then turns on the first switch 11.

[0039] Since the second load 102 is not yet in operation at the time of turning off the second switch 12 and no current flows through the second switch 12, the power supply control device 1 can prevent the failure of the second switch 12 due to the surge current when the second switch 12 is turned off.

[0040] When the turning on of the IG 103 is detected, if there is a device in which a change is detected due to an immediate interruption of the power supply by the user, the control device 3 notifies the user that the change occurs and then turns off the second switch 12 and then turns on the first switch 11.

[0041] For example, when the power-on of the IG 103 is detected, the control unit 3 causes the notification device 104 to issue a notification such as “output is temporarily suspended” when the user uses the external device.

[0042] Accordingly, the user can recognize through the power supply control device 1 that a change in an operating state of the second load 102 due to the turning on of the IG 103 is not a failure. [1-3. Process executed by the control device according to the first embodiment]

[0043] Next, a process executed by the control unit 3 of the power supply control device 1 will be described with reference to Fig. 5 to 8 described. Fig. 5 to 8 are flowcharts illustrating examples of processes executed by the controller 3 of the power supply control apparatus 1 according to the first embodiment.

[0044] When the switching off of the IG 103 is detected, the control unit 3 carries out a Fig. 5. Specifically, the control unit 3 switches, as shown in Fig. 5, first the first switch 11 is turned off and the second switch 12 is turned on (step S101).

[0045] Here, the control unit 3 turns off the third to sixth switches 13 to 16, while the seventh switch 17 remains on (step S101). Accordingly, the control unit 3 can operate the second load 102 by supplying the second load 102 with electric power from the auxiliary power supply 20 while the IG 103 is turned off.

[0046] Next, the control unit 3 determines whether the power-on of the IG 103 is detected (step S102). If the power-on of the IG 103 is not detected (step S102, No), the control unit 3 repeats a determination process in step S102 until the power-on of the IG 103 is detected.

[0047] If the activation of the IG 103 is detected (step S102, Yes), the control unit 3 leaves the first switch 11 off (step S103) and then executes a startup process (step S104). An example of the startup process will be described later with reference to Fig. 6 to 8. Subsequently, the control unit 3 performs the post-start process (step S105).

[0048] In the post-start process, for example, if a power failure of the first system 110 in the Fig. 4, the control device 3 turns off the third switch 13, the fourth switch 14, and the sixth switch 16, and supplies the first load 101 and the second load 102 with electric power from the auxiliary power supply 20. Accordingly, the power supply control device 1 can continue the operation of the first load 101 and the second load 102 even when the power failure occurs in the first system 110.

[0049] For example, if a power failure of the second system 120 occurs in the Fig. 4 is detected, the control device 3 turns off the third switch 13, the fifth switch 15, and the seventh switch 17 and supplies the first load 101 and the second load 102 with electric power from the main power supply 10. Accordingly, the power supply control device 1 can continue the operation of the first load 101 and the second load 102 even if the power failure occurs in the second system 120.

[0050] Next, the control unit 3 determines whether the shutdown of the IG 103 is detected (step S106). In response to determining that the shutdown of the IG 103 is not detected (step S106, No), the control unit 3 proceeds to step S105. In response to determining that the shutdown of the IG 103 is detected (step S106, Yes), the control unit 3 terminates the process and restarts the process from step S101.

[0051] In step S104, the control unit 3 performs, for example, a first start-up process which Fig. 6. Specifically, the control unit 3, as shown in Fig. 6, when starting the first starting process, it first determines whether the second load 102 is present whose power consumption is equal to or greater than the predetermined electric current (step S201).

[0052] In response to determining that there is no second load 102 whose power consumption is equal to or greater than the predetermined electric current (step S201, No), the controller 3 proceeds to step S205. In response to determining that there is a second load 102 whose power consumption is equal to or greater than the predetermined electric current (step S201, Yes), the controller 3 prompts the user to stop the operation of the second load 102 (step S202).

[0053] Accordingly, in the power supply control device 1, when the user stops the operation of the second load 102 in response to the stop request, if the second switch 12 is turned off while the IG 103 is turned on, no current flows through the second switch 12, and thus failure of the second switch 12 due to a current surge can be prevented.

[0054] Subsequently, the control unit 3 determines whether the power consumption of the second load 102 drops below the predetermined electric current (step S203). In response to determining that the power consumption of the second load 102 drops below the predetermined electric current (step S203, Yes), the control unit 3 switches the second switch 12 from the Fig. 4 illustrated state (step S205) and then turns on the first switch 11 (step S206).

[0055] Accordingly, in the power supply control device 1, since the current flowing through the second switch 12 decreases at the time the second switch 12 is turned off, even if the second switch 12 is turned off, failure of the second switch 12 due to a surge current can be prevented.

[0056] After step S206, the control unit 3 switches on the switches three to six 13 to 16 (step S207) and sets the Fig. 4. The control unit 3 forwards the process to step S105, which is shown in Fig. 5 is illustrated.

[0057] In response to determining that the power consumption of the second load 102 does not decrease below the predetermined electric current (step S203, No), the controller 3 determines whether a predetermined period of time has elapsed since the request to stop the operation of the second load 102 (step S204). In response to determining that the predetermined period of time has not yet elapsed (step S204, No), the controller 3 proceeds to step S203.

[0058] In response to determining that the predetermined time period has elapsed (step S204, Yes), the controller 3 proceeds to step S205. Accordingly, if the user stops the operation of the second load 102 in response to the stop request during the predetermined time period when the second switch 12 is turned off, the power supply control device 1 can prevent the failure of the second switch 12 due to the power surge and avoid a delay in starting a post-start operation.

[0059] In step S104, the control unit 3 can, for example, carry out a second start process which Fig. 7. Specifically, the control unit 3, as shown in Fig. 7, when starting the second startup process, the control unit 3 first determines whether the second load 102 whose power consumption is equal to or greater than the predetermined electric current is present (step S301). In response to determining that no second load 102 whose power consumption is equal to or greater than the predetermined electric current is present (step S301, No), the control unit 3 proceeds the process to step S304.

[0060] In response to determining that the second load 102 is present whose power consumption is equal to or greater than the predetermined electric current (step S301, Yes), the controller 3 notifies the user that the second load 102 should be stopped (step S302) and subsequently stops the second load 102 (step S303). After that, the controller 3 turns off the second switch 12 (step S304), then turns on the first switch 11 (step S305), and turns on the third to sixth switches 13 to 16 (step S306). The controller 3 proceeds the process to step S105, which is shown in Fig. 5 is illustrated.

[0061] Since the second load 102 is not yet in operation at the time of turning off the second switch 12 and no current flows through the second switch 12, the power supply control device 1 can prevent the failure of the second switch 12 due to the surge current when the second switch 12 is turned off.

[0062] In step S104, the control unit 3 can, for example, carry out a third start process which Fig. 8. Specifically, the control unit 3, as shown in Fig. 8, when starting the third startup process, it first determines whether there is a device in which a change is detected due to an immediate interruption of the electrical power supply by the user (step S401).

[0063] The device in which the user detects a change due to an immediate interruption is, for example, a tachograph with a built-in display, an electronic device powered by an electrical power supply from the socket in the vehicle, or an electrical appliance.

[0064] In response to determining that no device is present in which a change is detected due to an immediate interruption by the user (step S401, No), the control unit 3 advances the process to step S403. In response to determining that a device is present in which a change is detected due to an immediate interruption by the user (step S401, Yes), the control unit 3 notifies the user that a change in an operating state of the device in use occurs (step S402). The control unit 3 turns off the second switch 12 (step S403), then turns on the first switch 11 (step S404), turns on the third to sixth switches 13 to 16 (step S405), and advances the process to step S105, which is shown in Fig. 5 is illustrated.

[0065] Here, the supply of electric power to the second load 102 is immediately interrupted by turning off the second switch 12, and the operating state of the second load 102 may change due to a decrease in the electric power supply. When the first switch 11 is turned on and the operation of the first load 101 is started, the voltage of the main power supply 10 temporarily drops, and the operating state of the second load 102 may change due to a decrease in the supplied electric power.

[0066] Therefore, as described above, the power supply control device 1 notifies the user in advance when a change in the operating state of the device in use occurs. Accordingly, the user can recognize through the power supply control device 1 that the change in the operating state of the device due to the powering on of the IG 103 is not caused by the device failure. [2. Second Embodiment][2-1. Structure of the Power Supply Control Device According to the Second Embodiment]

[0067] Next, a configuration of a power supply control apparatus 1A according to a second embodiment will be described with reference to Fig. 9 described. Fig. Fig. 9 is a diagram showing a configuration example of the power supply control device 1A according to the second embodiment. The power supply control device 1A is mounted in an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle that runs on electric power supplied from a Fig. 9 illustrated main power supply 10A.

[0068] As in Fig. As illustrated in Figure 9, the power supply control device 1A is connected to a main power supply 10A via a DC / DC converter (hereinafter referred to as "DC / DC 10B"). The power supply control device 1A is connected to a sub-power supply 20A. The power supply control device 1A is connected to a (1-1)th load 201, a (1-2)th load 202, a (2-1)th load 203, and a (2-2)th load 204.

[0069] The power supply control device 1A is connected to an IG 10C. After power-on, the IG 10C outputs a power-on signal to the power supply control device 1A. In the power-off state, the IG 10C outputs an end signal to the power supply control device 1A.

[0070] The main power supply 10A includes a high-voltage battery capable of outputting a higher voltage than the auxiliary power supply. The high-voltage battery is, for example, a lithium-ion battery. The DC-DC converter 10B regulates the voltage of the main power supply 10A and outputs the voltage to the power supply control device 1A.

[0071] The main power supply 10A supplies electric power to the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 in addition to a motor that drives the vehicle via the DC / DC 10B and the power supply control device 1A.

[0072] The auxiliary power supply 20A includes a low-voltage battery capable of outputting a lower voltage than the high-voltage battery. The low-voltage battery is, for example, a lead-acid battery. The low-voltage battery may be a lithium-ion battery. The auxiliary power supply 20A supplies electric power to the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 through the power supply control device 1A.

[0073] The (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 are electrical loads mounted on the vehicle. The (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 include, for example, an engine control device, a steering control device, a brake control device, an audio device, and a video display device.

[0074] The (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 include, for example, a tachograph, a safety device, and an in-vehicle power outlet for supplying power to an external device. In the following description, the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 are collectively referred to simply as loads.

[0075] In this embodiment, it is assumed that the (1-1)th load 201 and the (1-2)th load 202 are loads with the same function. In this embodiment, it is assumed that the (2-1)th load 203 and the (2-2)th load 204 are loads with the same function. However, the (2-1)th load 203 and the (2-2)th load 204 have different functions than the (1-1)th load 201 and the (1-2)th load 202.

[0076] The (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 each include a capacitor 5. The capacitor 5 smoothes and stabilizes the electric current supplied from the power supply control device 1A and stores it.

[0077] Accordingly, the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 can maintain operation even if the electric power supply is immediately cut off by the power supply control device 1A, while maintaining the electric power stored in the capacitor 5.

[0078] The power supply control device 1A includes a first switch 21, a second switch 22, a third switch 23, a fourth switch 24, a fifth switch 25, a sixth switch 26 and a controller 3A.

[0079] The power supply control device 1A further includes a first voltage sensor 41, a second voltage sensor 42, a third voltage sensor 43, a fourth voltage sensor 44, a fifth voltage sensor 45, a sixth voltage sensor 46, and a seventh voltage sensor 47.

[0080] The first switch 21 is a switch that connects the main power supply 10A to a load. The second switch 22 is a switch that connects the sub power supply 20A to a load. Specifically, the first switch 21 is connected at one end to the main power supply 10A via the DC / DC converter 10B and at the other end to a common wiring 100 shared by the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204. The second switch 22 is connected at one end to the sub power supply 20A and at the other end to the common wiring 100.

[0081] The third switch 23 is a switch that connects the common wiring 100 and the (1-1)th load 201. The fourth switch 24 is a switch that connects the common wiring 100 and the (1-2)th load 202. The fifth switch 25 is a switch that connects the common wiring 100 and the (2-1)th load 203. The sixth switch 26 is a switch that connects the common wiring 100 and the (2-2)th load 204.

[0082] The first voltage sensor 41 detects a voltage of a connecting line connecting the first switch 21 and the DC / DC converter 10B and outputs a detection result to the control unit 3A. The second voltage sensor 42 detects the voltage of a connecting line between the second switch 22 and the auxiliary power supply 20A and outputs a detection result to the control unit 3A.

[0083] The third voltage sensor 43 detects a voltage of a connecting line connecting the third switch 23 and the (1-1)th load 201 and outputs a detection result to the control unit 3A. The fourth voltage sensor 44 detects the voltage of a connecting line connecting the fourth switch 24 and the (1-2)th load 202 and outputs a detection result to the control unit 3A.

[0084] The fifth voltage sensor 45 detects a voltage of a connecting line connecting the fifth switch 25 and the (2-1)th load 203 and outputs a detection result to the control unit 3A. The sixth voltage sensor 46 detects a voltage of a connecting line connecting the sixth switch 26 and the (2-2)th load 204 and outputs a detection result to the control unit 3A. The seventh voltage sensor 47 detects a voltage of the common wiring 100 and outputs a detection result to the control unit 3A.

[0085] The control unit 3A includes a microcomputer with a CPU, a ROM, and a RAM, as well as various circuits. The control unit 3A controls the first to sixth switches 21 to 26 by executing a power supply control program stored in the ROM and using the RAM as a work area.

[0086] A portion or the entire control unit 3A may be implemented by hardware such as an application-specific integrated circuit (ASIC) or a field-programmable gate array (FPGA).

[0087] The control unit 3A electrically connects (conducts) the two terminals of the first to sixth switches 21 to 26 by turning on the first to sixth switches 21 to 26, respectively. The control unit 3A electrically disconnects the two terminals of the first to sixth switches 21 to 26 by turning off the first to sixth switches 21 to 26, respectively. [2-2. Operation example of a power supply control device according to the second embodiment]

[0088] Next, an operation example of the power supply control device 1A according to the second embodiment will be described with reference to Fig. 10 to 13 described. Fig. 10 to 13 are diagrams illustrating the operation example of the power supply control apparatus 1A according to the second embodiment.

[0089] When the vehicle is in parking mode, ie when the IG is switched off, as in Fig. As illustrated in Figure 10, the control unit 3A turns off the first switch 21 and turns on the second switch 22. Furthermore, the control unit 3A turns on the third to sixth switches 23 to 26.

[0090] Accordingly, the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 can continue to be driven by electric power supplied from the sub-power supply 20A by the power supply control device 1A during a period in which the IG is turned off.

[0091] Thereafter, the control device 3A supplies electric power from the main power supply 10A to the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203 and the (2-2)th load 204 when the IG 10C is turned on and a start signal is input from the IG 10C.

[0092] Here, in a state that is Fig. 10, that is, when the IG 10C is turned on during the electric power supply from the sub-power supply 20A to a load and the first switch 21 is turned on to start the electric power supply from the main power supply 10A to the load, a surge current may occur, causing a failure of the second switch 22.

[0093] So if the IG 10C is switched on while the Fig. 10 illustrated IG 10C is switched off, the control unit 3 switches off the second switch 22, as in Fig. 11, and then switches on the first switch 21 as shown in Fig. 12 is illustrated.

[0094] Since the second switch 22 is already turned off and no current flows through the common wiring 100 when the first switch 21 is turned on, the power supply control device 1A can prevent failure of the second switch 22 even if a surge current occurs by turning on the first switch 21.

[0095] Then the control unit 3A switches, as in Fig. 13, the second switch 22 is turned on. That is, when the IG 10C is turned on, the control unit 3A turns on the first switch 21 after turning off the second switch 22, and then turns on the second switch.

[0096] Accordingly, the power supply control device 1A can charge the sub-power supply 20A and at the same time prevent a failure of the second switch 22 by turning the second switch 22 back on after the electric power supply from the main power supply 10A to a load is stabilized.

[0097] When the IG is switched from off to on, the controller 3 turns off the second switch 22 and then turns on the first switch 21 at a timing at which the operation of each load is not stopped even if the electric power supply of each load is cut off immediately.

[0098] Specifically, when the IG 10C is turned on, the control device 3A turns on the first switch 21 for a period of time ranging from the turning off of the second switch 22 until the elapse of a period of time during which each load can maintain operation by electric current of the capacitor 5 included in the load.

[0099] Accordingly, after turning off the second switch 22 in a state where the first switch 21 is turned off, the power supply control device 1A can maintain the operation of each load by turning on the first switch 21 while maintaining the operation of each load by the electric current of the capacitor 5 even if the electric power supply of each load is immediately cut off. [2-3. Process executed by the control unit according to the second embodiment]

[0100] Next, a process executed by the control unit 3A of the power supply control device 1A will be described with reference to Fig. 14 described. Fig. 14 is a flowchart illustrating an example of the process executed by the controller 3A of the power supply control apparatus 1A according to the second embodiment.

[0101] When the IG 10C is switched from off to on, the control unit 3A starts a Fig. 14. Therefore, the control unit 3A starts the Fig. 14 illustrated process from a state in which the power supply control device 1A is in the Fig. 10, ie, in a state in which the first switch 21 is turned off and the second to sixth switches 22 to 26 are turned on.

[0102] Specifically, the control unit 3A, as shown in Fig. 14, when the IG 10C is turned on, it first determines whether the load is operating (step S501). In response to determining that the load is operating (step S501, Yes), the control unit 3A leaves the first switch 21 off and turns off the second switch 22 (step S502). Accordingly, the power supply control device 1A is in a Fig. 11 illustrated state.

[0103] That is, when at least one of the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 is operating, the control device 3A keeps the first switch 21 off and turns off the second switch 22. Accordingly, the control device 3A may be in a state where no current temporarily flows through the common wiring 100.

[0104] Thereafter, the controller 3A proceeds the process to step S503. In response to determining that the load is not operating (step S501, No), the controller 3A proceeds the process to step S503. That is, if the (1-1)th load 201, the (1-2)th load 202, the (2-1)th load 203, and the (2-2)th load 204 are not operating, the controller 3A proceeds the process to step S503.

[0105] In step S503, the control unit 3A turns on the first switch 21 and leaves the second switch 22 off. In response to No in step S501, the control unit 3A turns the second switch 22 from on to off. Accordingly, the power supply control device 1A is in a Fig. 12 illustrated condition.

[0106] Thereafter, the control unit 3A leaves the first switch 21 on, turns on the second switch 22 (step S504), and ends the process. Accordingly, the power supply control device 1A is in a Fig. 13 illustrated state.

[0107] The control unit 3A may also turn off the second switch 22 when the charging of the auxiliary power supply 20A is completed. In this case, the control unit 3 determines whether the charging of the auxiliary power supply 20A is completed based on the detection result of the second voltage sensor 42.

[0108] After the charging of the auxiliary power supply 20A is completed and the second switch 22 is turned off, the control unit 3A can turn the second switch 22 back on if a storage capacity of the auxiliary power supply 20A is equal to or less than a predetermined storage capacity. In this case, the control unit 3A determines whether the storage capacity of the auxiliary power supply 20A is equal to or less than the predetermined storage capacity based on the detection result of the second voltage sensor 42. [2-4. Operation of the power supply control device according to the second embodiment at the time of detection of a ground fault]

[0109] In the power supply control device 1A, in the Fig.13, that is, in a state where the IG is turned on and the first to sixth switches 21 to 26 are finally turned on, a ground fault may occur between the power supply control device 1A and the DC / DC 10B, the sub-power supply 20A, or a load.

[0110] Therefore, the control device 3A detects the occurrence of a ground fault based on the detection results of the voltage sensors one to seven 41 to 47, specifies an occurrence point of the ground fault, and performs fail-safe control of breaking the connection between the ground fault point and the power supply control device 1A.

[0111] If the voltage detected by any of voltage sensors one through seven (41 through 47) is equal to or less than a ground fault threshold, control unit 3A determines that a ground fault has occurred. In response to detecting that a ground fault has occurred, control unit 3A turns off all switches three through six (23 through 26), which are the load switches in a state where the first switch 21 and the second switch 22 are turned on.

[0112] When a ground fault occurs between the power supply control device 1A and a load, the voltages detected by the first voltage sensor 41 and the second voltage sensor 42 return to their original state by turning off all switches 3 through 6 (23 through 26). When the voltage detected by the first voltage sensor 41 or the second voltage sensor 42 returns to a threshold voltage or higher, the control device 3A determines that a ground fault has occurred between the power supply control device 1A and a load.

[0113] In this case, control unit 3A sequentially turns on switches 23 through 26, three through six, to specify the load where the ground fault occurs. Specifically, control unit 3A first turns on switch 23 (and turns off switches 24 through 26).

[0114] Here, when the voltage detected by the third voltage sensor 43 (or that detected by the first voltage sensor 41 or the second voltage sensor 42) is equal to or less than a threshold value, the control device 3A determines that a ground fault occurs between the (1-1)th load 201 and the power supply control device 1A, that is, that a ground fault occurs in the (1-1)th load 201.

[0115] In this case, the control device 3A turns off only the third switch 23, which is closest to the (1-1)th load 201 as the ground fault point and can disconnect the load, and turns on the other switches. Accordingly, the control device 3A can perform the fail-safe control of disconnecting the ground fault point from the power supply control device 1A.

[0116] On the other hand, when the third switch 23 is turned on (switch four 24 to switch six 26 are turned off), if the voltage detected by the third voltage sensor 43 returns to the threshold value or more, the control device 3A determines that no ground fault occurs between the (1-1)th load 201 and the power supply control device 1A, that is, the (1-1)th load 201 is normal.

[0117] In this case, the control device 3A turns on the fourth switch 24 (the third switch 23 and the fifth switches 25 to 26 are turned off) and similarly specifies whether a ground fault occurs between the (1-2)th load 202 and the power supply control device 1A, that is, whether a ground fault occurs in the (1-2)th load 202. After that, the control device 3A similarly sequentially turns on the fifth switch 25 and the sixth switch 26 until a load at which a ground fault occurs can be specified, and then specifies the load at which the ground fault occurs.

[0118] When the specification of the load where the ground fault occurs is completed, the control device 3A turns off a load breaker closest to the ground fault point that turns off the specified load and turns on other load breakers to execute the fail-safe control.

[0119] For example, if the control device 3A indicates that the ground fault point is the (2-1)th load 203 and the power supply control device 1A, the control device 3A turns off the fifth switch 25, which is a load switch closest to the ground fault point and capable of disconnecting the specified load, and turns on other load switches (the third switch 23, the fourth switch 24, and the sixth switch 26). Accordingly, the control device 3A turns off the (2-1)th load 203, which is the ground fault point, and executes fail-safe control with a load other than the (2-1)th load 203.

[0120] When the control device 3A detects the occurrence of the ground fault and turns off all the third to sixth switches 23 to 26, which are the load switches in a state where the first switch 21 and the second switch 22 are turned on, if the voltage detected by the first voltage sensor 41 or the second voltage sensor 42 does not return to the threshold value or more, the control device 3A determines that a ground fault occurs between the power supply control device A1 and the DC / DC 10B or between the power supply control device A1 and the sub-power supply 20A.

[0121] In this case, the control unit 3A turns off the first switch 21, turns on the second switch 22, and turns on the third to sixth switches 23 to 26. Here, when a ground fault occurs between the power supply control device A1 and the DC / DC converter 10B, the voltage detected by the first voltage sensor 41 remains at or below the threshold value even if the first switch 21 is turned off. On the other hand, if no ground fault occurs between the power supply control device A1 and the DC / DC converter 10B, turning off the first switch 21 causes the voltage detected by the first voltage sensor 41 to return to or above the threshold value.

[0122] Therefore, when the first switch 21 is turned off, the second switch 22 is turned on, and the third to sixth switches 23 to 26 are turned on, when the voltage detected by the first voltage sensor 41 is equal to or less than the threshold value, the control device 3A determines that a ground fault occurs between the power supply control device A1 and the DC / DC 10B, that is, a ground fault occurs on the main power supply 10A side.

[0123] In this case, the control device 3A turns off the first switch 21 which is closest to the ground fault point and is capable of interrupting the ground fault point, turns on the second switch 22, and turns on the third to sixth switches 23 to 26, thereby interrupting the main power supply 10A which is the ground fault point, and executing the fail-safe control using the sub-power supply 20A.

[0124] On the other hand, when the first switch 21 is turned off, the second switch 22 is turned on, and the third to sixth switches 23 to 26 are turned on, when the voltage detected by the first voltage sensor 41 returns to the threshold value or more, the control device 3A determines that no ground fault occurs between the power supply control device A1 and the DC / DC 10B, that is, the main power supply side is normal.

[0125] In this case, the control device 3A then turns off the second switch 22, turns on the first switch 21, turns on the third to sixth switches 23 to 26, and similarly determines whether a ground fault occurs between the power supply control device A1 and the sub-power supply 20A based on the voltage detected by the second voltage sensor 42.

[0126] When the control device 3A determines that a ground fault occurs between the power supply control device A1 and the sub-power supply 20A, that is, a ground fault occurs in one side of the sub-power supply 20A, the control device 3A turns off the second switch 22, which is a switch closest to the ground fault point and capable of interrupting the ground fault point, turns on the first switch 21, and turns on the third to sixth switches 23 to 26, thereby interrupting the side of the sub-power supply 20A, which is the ground fault point, and executes the fail-safe control using the main power supply 10A.

[0127] Thus, when a ground fault occurrence point is determined, the control device 3A turns off a switch closest to the ground fault occurrence point, namely the first switch 21, the second switch 22, and the load switches (switches 3 through 6, 23 through 26). In other words, the control device 3 turns off the switch that can shut off the ground fault occurrence point. Accordingly, the control device 3A can perform fail-safe control by isolating the ground fault occurrence point from the power supply control device 1A. [3. Appendix]

[0128] The elements of this disclosure are illustrated below as an appendix. (1) A power supply control device comprising: a first switch coupled between a main power supply and a load; a second switch coupled between a secondary power supply and the load; and a controller configured to perform the on / off control of the first switch and the second switch, wherein the control unit is set up so that it: in response to turning off an ignition switch, turns off the first switch and turns on the second switch; and in response to the ignition switch being turned on, turns off the second switch and then turns on the first switch. (2) The power supply control device according to (1), wherein the control unit is arranged to turn on the first switch after turning off the second switch and then to turn on the second switch in response to the ignition switch being turned on. (3) The power supply control device according to (1) or (2), wherein the control unit is arranged to switch the first switch on for a period of time in response to the ignition switch being switched on, the period of time ranging from the time at which the second switch is switched off to the time at which a period of time elapses during which the load can remain in operation by the electrical current of a capacitor of the load. (4) The power supply control device according to any one of (1) to (3), further comprising: a first system arranged to supply electrical power from the main power supply to the load via the first switch; a second system arranged to supply electrical power from the auxiliary power supply to the load via the second switch; and a switch coupled between the first system and the second system, wherein the control unit is set up so that it: in response to the ignition switch being turned off, turns off the system-wide switch; and in response to the ignition switch being turned on, turns on the system-wide switch when the first switch is turned on. (5) The power supply control device according to any one of (1) to (4), further comprising a load switch coupled between a connecting wiring and each of a plurality of loads, the connecting wiring connecting the first switch and the second switch, wherein the control device is configured so that, when an earth fault is detected, it specifies a point of occurrence of the earth fault and opens a switch from the first switch, the second switch, and the load switch that is closest to the point of occurrence of the earth fault. (6) A non-transitory computer-readable storage medium storing a power supply control program that causes a controller to execute a process comprising Carrying out the on / off control of a first switch arranged to connect a main power supply to a load and a second switch arranged to connect a sub-power supply to the load, the method further comprising: Turning off the first switch and turning on the second switch in response to turning off an ignition switch; and Turning off the second switch and then turning on the first switch in response to the ignition switch being turned on.

[0129] Further effects and modifications can be readily devised by those skilled in the art. Therefore, broader aspects of this invention are not limited to the specific details and representative embodiments illustrated and described above. Therefore, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2009-83527

[0002]

Claims

[1] A power supply control device comprising: a first switch coupled between a main power supply and a load; a second switch coupled between a secondary power supply and the load; and a controller configured to perform the on / off control of the first switch and the second switch, wherein the control unit is set up so that it: in response to turning off an ignition switch, turns off the first switch and turns on the second switch; and in response to the ignition switch being turned on, turns off the second switch and then turns on the first switch. [2] The power supply control device according to claim 1, wherein the controller is configured to turn on the first switch after turning off the second switch and then turn on the second switch in response to turning on the ignition switch. [3] A power supply control device according to claim 1 or 2, wherein the control device is arranged to turn on the first switch during a period of time in response to the turning on of the ignition switch, the period of time ranging from the time at which the second switch is turned off to the time at which a period of time elapses during which the load can remain in operation by the electric current of a capacitor of the load. [4] A power supply control device according to any one of claims 1 to 3, further comprising: a first system arranged to supply electrical power from the main power supply to the load via the first switch; a second system arranged to supply electrical power from the auxiliary power supply to the load via the second switch; and a cross-system switch coupled between the first system and the second system, wherein the control unit is set up so that it: in response to the ignition switch being turned off, turns off the system-wide switch; and in response to the ignition switch being turned on, turns on the system-wide switch when the first switch is turned on. [5] Power supply control device according to one of claims 1 to 4, further comprising a load switch coupled between a connecting wiring and each of a plurality of loads, the connecting wiring connecting the first switch and the second switch, wherein the control device is configured so that, when an earth fault is detected, it specifies a point of occurrence of the earth fault and opens a switch from the first switch, the second switch, and the load switch that is closest to the point of occurrence of the earth fault. [6] Non-transitory computer-readable storage medium storing a power supply control program that causes a controller to execute a process, the process comprising Carrying out the on / off control of a first switch coupled between a main power supply and a load and a second switch coupled between a sub-power supply and the load, the method further comprising: Turning off the first switch and turning on the second switch in response to turning off an ignition switch; and Turning off the second switch and then turning on the first switch in response to the ignition switch being turned on.

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