Vehicle power-supply control device and method for controlling vehicle power-supply control device

Abstract

This vehicle power-supply control device comprises: a plurality of loads (20) that operate with power supplied from a power supply; a plurality of semiconductor switching elements that are disposed in a power supply line (70) that electrically connects the power supply (60) and the loads (20) to electrically connect or disconnect between the power supply (60) and the loads (20); and a controller that controls on / off of the semiconductor switching elements. The plurality of semiconductor switching elements and the plurality of loads (20) are in a one-to-one correspondence. The controller controls on / off for each of the plurality of semiconductor switching elements on a basis of at least one piece of information among operation information of an on-vehicle device operated by a user, battery information of a battery, and operation information of the loads (20).

Description

Vehicle power supply control device and control method for vehicle power supply control device

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

[0002] A vehicle power supply control device has been known in the past that supplies power to electrical loads that operate when the ignition is on, even when the ignition is not on (see, for example, Patent Document 1). In the vehicle power supply control device described in Patent Document 1, the on-board electrical loads that operate when the ignition is on are divided into an IG group that receives power only when the ignition is on and a PAIG group that receives power even when the ignition is not on. A power supply relay PAIG, which is different from the power supply relay IG that is provided between the on-board electrical loads of the IG group and the on-board power supply, is provided between the on-board electrical loads of the PAIG group and the on-board power supply. When the ignition is not on, the power supply relay PAIG is closed to allow power to be supplied to the on-board electrical load, and ignition information is transmitted to the on-board electrical load via a communication line.

[0003] Japanese Patent Application Laid-Open No. 2007-191015

[0004] In the vehicle power supply control device described in Patent Document 1, since a large number of vehicle electrical loads are connected downstream of the power supply relay PAIG, when the power supply relay PAIG is turned on to supply power to the loads connected directly below the PAIG, power is also supplied to the large number of loads connected downstream of the power supply relay PAIG, resulting in a problem of large power consumption.

[0005] An object of the present invention is to provide a vehicle power supply control device and a control method for a vehicle power supply control device that can reduce power consumption.

[0006] The present invention solves the above problem by connecting multiple IPDs and multiple loads to a power supply line in a one-to-one correspondence, and controlling the on / off of each of the multiple IPDs based on at least one of the following information: operation information of an in-vehicle device operated by a user, battery information, and operation information of the load.

[0007] According to the present invention, power consumption can be reduced.

[0008] Fig. 1 is a block diagram of a vehicle power supply system according to this embodiment, and Fig. 2 is a flowchart showing an example of the procedure of a software update method according to this embodiment.

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a vehicle power supply control device and a control method for a vehicle power supply control device according to the present invention will be described with reference to the accompanying drawings.

[0010] 1 is a block diagram of a vehicle power supply system 100 according to this embodiment. The vehicle power supply system 100 is mounted on a vehicle and switches between electrical conduction and interruption between a power source and multiple loads. The vehicle power supply system 100 includes multiple intelligent power devices (IPDs) 10, loads 20, a master control unit (MCU) 30, an in-vehicle infotainment (IVI) system 40, a battery control unit (BCU) 50, a power source 60, and a power supply line 70.

[0011] The multiple IPDs 10 are provided on a power supply line 70 that electrically connects a power source 60 and multiple loads 20, and are semiconductor switching elements that connect or disconnect the power source 60 and the loads 20. The IPDs 10 include transistors such as MOSFETs and protection circuits. The IPDs 10 switch between connection and disconnection in response to on / off commands sent from the MCU 30. The protection circuit detects current flowing through the circuits within the IPDs, and if the current is higher than an upper limit, it disconnects the current regardless of the command value from the MCU 30.

[0012] The multiple IPDs 10 are each connected to a branched power supply line 70 so as to pass current from the power supply 60 to the multiple loads 20. Note that IPD 10 is a collective term for IPDs 11 to 17. IPD 11 is connected to correspond to Meter 21, IPD 12 is connected to correspond to interior illumination 22, IPD 13 is connected to correspond to ADAS 23, IPD 14 is connected to correspond to HUD 24, IPD 15 is connected to correspond to Radar 25, IPD 16 is connected to correspond to VDC 26, and IPD 17 is connected to correspond to display 27. In other words, each of the multiple IPDs 10 is connected to one load 20 downstream, and switches between conduction and cut-off of the current flowing from the power supply 60 to one load 20.

[0013] The multiple loads 20 are in-vehicle devices that operate using power supplied from a power source. Examples of the multiple loads 20 include a meter 21, an interior illumination 22, an ADAS 23, a HUD 24, a radar, a VDC 26, and a display 27, which are connected downstream of the IPDs 11 to 17. The meter 21 is a speedometer and is provided on an instrument panel located in front of the driver. The interior illumination (short for illumination) 22 is an interior component within the vehicle. The ADAS (Advanced Driver Assistance System) 23 is an advanced driving assistance system. The HUD (Head Up Display) 24 is a display device that is displayed on the windshield. The radar 25 is a distance measuring device that measures the distance to an obstacle in front of or around the vehicle. The VDC (Vehicle Dynamic Control) 26 is a system that monitors the driver's vehicle operation and / or vehicle movement, and controls brake pressure, engine or motor output, etc. according to the driving conditions. The display 27 is a touch-panel display device installed on the instrument panel that displays map information, etc. The multiple loads 20 are not limited to the above-mentioned Meter 21, etc., but also include other in-vehicle devices such as lighting devices such as headlights and room lamps. The multiple IPDs 10 and the multiple loads 20 are in one-to-one correspondence. Each of the multiple loads 20 has a control unit (electronic control unit (ECU)) that stores software for controlling the device.

[0014] The MCU 30 is a control unit configured by a computer equipped with hardware and software, and includes a memory storing programs and a CPU that executes the programs stored in the memory. The MCU 30 is connected to the ECUs, IVI 40, BCU 50, and other ECUs included in the multiple loads 20 via an in-vehicle communication network. The MCU 30 has functions such as controlling the on / off of the IPD 20, updating software included in the ECUs, and controlling the loads 20. The MCU 30 has an IPD control unit 31 and a software update unit 32 as functional blocks. The MCU 30 is not limited to the functions of the IPD control unit 31 and the software update unit 32, and may also have a communication function, for example, for communicating with a server outside the vehicle. The MCU 30 is not necessarily limited to a single control unit, but may be configured with multiple control units.

[0015] The IVI 40 is a system that integrates a navigation system that provides map information and route guidance, an entertainment system that provides entertainment elements such as music and video, etc. The IVI 40 controls in-vehicle devices such as the display 27 and speakers to provide information to the user.

[0016] The BCU 50 is a control unit that manages the state of the battery and controls the charging and discharging of the battery. The BCU 50 transmits battery information such as the state of charge (SOC) of the battery to the MCU 30.

[0017] The power supply 60 is a secondary battery (battery) such as a lithium-ion battery or a lead battery. The power supply 60 may also be a generator connected to a power-generating engine, a drive motor that generates power during regeneration, a DC-DC converter for stepping down the voltage from the driving battery, etc. The power supply line 70 is a branched harness that passes current from the power supply 60 to multiple loads 20.

[0018] Next, we will explain the control function of the MCU 30. The IPD control unit 31 controls the on / off of each of the multiple IPDs based on at least one of operation information of an in-vehicle device operated by a user, battery information of the battery, and operation information of the load 20.

[0019] The operation information indicates that an in-vehicle device has been operated by a user, the status of the operated in-vehicle device, etc. The operation information is, for example, door opening / closing information, operation information of the display 27, etc. For example, assume that the display 27 has the following specifications: If a user gets out of the vehicle while the display 27 is displaying an image, the display 27 turns off after a predetermined time (e.g., 30 seconds or 1 minute) has elapsed since the user got out of the vehicle. In this specification, the IVI 40 first transmits video information to the display 27, and the display 27 displays the image. When the user opens or closes a door, the MCU 30 acquires door opening / closing information from a sensor included in the load 20 that detects door opening / closing. The MCU 30 transmits a command to switch the IPD 17 off after a predetermined time has elapsed since the MCU 30 acquired the door opening / closing information. Furthermore, if the user operates the display 27 before the predetermined time has elapsed, the display 27 transmits operation information to the MCU 30. The MCU 30 extends the predetermined time from the time the user's operation information is received from the display 27 until the IPD 17 is turned off. As a result, the MCU 30 controls the on / off of the IPD 17 based on the operation information of the in-vehicle device.

[0020] Next, the on / off control of the IPD 10 based on battery information will be described. Assume, for example, that the vehicle is stopped and a user is in the vehicle. The vehicle specifications are such that, when the battery's SOC is below a predetermined SOC threshold, the loads 20, such as the meter 21 and the interior illumination 22, that have a low impact on the user are turned off. In this configuration, for example, a user inside the vehicle operates the display 27 to watch a video, such as a movie. The MCU 30 acquires battery information from the BCU 50. When the battery's SOC falls below the predetermined SOC threshold, the MCU 30 notifies the user that the remaining battery capacity is low, that the vehicle will enter a power-saving mode, or that the meter 21 and the interior illumination 22 will automatically turn off when the power-saving mode is entered. The user is notified by displaying the information on the display 27. The notification to the user may be omitted. The MCU 30 then turns off the IPDs 11 and 12 connected to the meter 21 and the interior illumination 22. As a result, the MCU 30 controls the on / off of the IPDs 11 and 12 based on the battery information of the battery.

[0021] Next, the on / off control of the IPD 10 based on operation information (feedback information) of the load 20 will be described. As will be described later, when updating software of a control unit included in the load 20, the software update unit 32 transmits a command to update the software to the load 20. For example, when updating software of a control unit included in the ADAS 23, the IPD control unit 31 transmits a command to turn on the IPD 13. After the IPD 13 is turned on, the software update unit 32 transmits a command to start the software update (active command) to the ADAS 23. The ADAS 23 starts the software update based on a command from the MCU 30. When the software update is complete, the ADAS 23 transmits a completion command to the MCU 30 indicating that the software update has been completed. The software completion command corresponds to operation information of the load 20. When the IPD control unit 31 receives the completion command, it turns off the IPD 13. As a result, the MCU 30 controls the on / off of the IPD 13 based on the operation information of the ADAS 23.

[0022] The software update unit 32 updates the software of the control unit included in the load 20. The software includes a program for controlling the load 20. The software update unit 32 communicates with an external server (over-the-air communication), downloads data for the software to be updated, and stores it in memory. The data download may be performed while the vehicle is running or while the vehicle is stopped. The downloaded data may also be stored in memory built into the control units of the multiple loads 20. The software update unit 32 designates loads (hereinafter also referred to as update target loads) to be updated from among the multiple loads 20. If there are multiple update target loads, the software is updated in descending order of priority. The priority is determined based on factors such as the impact on driving and the impact on the user. Specifically, a load 20 whose function cannot be enabled or disabled by the user and is related to driving has the highest priority. For example, the VDC 26 has the highest priority. Next, a load 20 whose function can be enabled or disabled by the user and is related to driving has the second highest priority. For example, the ADAS 23 and the radar 25 are the loads with the second highest priority. Next, the load 20 that is not related to driving and has little impact on the user even if its function is disabled is the lowest priority. For example, the interior illumination 22 and the display 27 are the loads with the lowest priority. Note that the priority is not limited to three levels, and may be two levels or four or more levels.

[0023] The software update unit 32 then transmits an activation command to the control unit included in the load to be updated, in descending order of priority, to update the software. In response to the activation command, the control unit updates the software by switching to pre-downloaded software. After completing the software update, the control unit may delete unnecessary software from its internal memory.

[0024] The MCU 30 may control the load 20 based on at least one of operation information of an in-vehicle device operated by a user, battery information of the battery, operation information of the load 20, and operation information of the IPD control unit 31. For example, when the IPD control unit 31 sends an off command to the IPD 10, the MCU 30 sends the off command to a control unit included in the load 20 to be turned off. For example, to turn off the IPD 13 connected to the ADAS 23, the MCU 30 outputs an off command to the control unit included in the ADAS 23. Upon receiving the off command to turn off the IPD 13, the control unit included in the ADAS 23 stores control status information indicating the current control status of the ADAS 23 in an internal memory before turning off the IPD 13. The control status information may be, for example, a user-set following distance when following a leading vehicle in autonomous driving. The ADAS 23 performs autonomous driving during its next operation, maintaining the previously set inter-vehicle distance and following the preceding vehicle. That is, before the IPD 13 is turned off, the ADAS stores information necessary for the next startup. As a specific example, if the trigger for turning off the ADAS 23 is the display 27, the display 27 transmits an operation signal to the MCU 30 indicating that an operation to turn off the display function has been performed. Based on the operation signal from the display 27, the IPD control unit 31 transmits an IPD 13 off command to the control unit included in the ADAS 23. This notifies the ADAS 23 in advance that the IPD 13 will be turned off. While the specific example describes an example in which the ADAS 23, which is another load, is turned off when a user operates the display 27, other loads may be used instead of the display 27, such as a push switch or HFM operated by the user. Other loads may also be used, not limited to the ADAS 23.

[0025] Next, a software update method executed by the MCU 30 will be described with reference to Fig. 2. Fig. 2 is a flowchart of the software update method according to this embodiment. Note that the control flow shown in Fig. 2 is executed when the vehicle is stopped and the main switch of the vehicle is switched from on to off as a trigger.

[0026] In step S1, the MCU 30 displays a screen on the display 27 to confirm the user's intention as to whether or not to update the software. The MCU 30 confirms the user's intention through a touch operation on the display 27. In step S2, the MCU 30 acquires battery information from the BCU 50 and checks whether the SOC of the battery is equal to or exceeds the SOC threshold (SOC ｔｈ１ ) or more. ｔｈ１ ) is a threshold for determining whether or not to update the software, and is set to, for example, 20%. ｔｈ１ ) is set according to the remaining capacity required to start the engine, for example. ｔｈ１ ), the MCU 30 ends the control flow without performing the software update.

[0027] The battery SOC is the SOC threshold (SOC ｔｈ１ ), the SOC of the battery is equal to or greater than the SOC threshold (SOC ｔｈ２ ) is determined. ｔｈ２ ) is a threshold value for determining whether to select the normal mode or the power saving mode. ｔｈ２ ) is set to an SOC higher than the lower limit of SOC (for example, 60%) to prevent deterioration of the battery, for example, 65%. The power saving mode is a mode that reduces power consumption more than the normal mode, and reduces the operating load more than the normal mode. For example, in the power saving mode, the meter 21 and the interior illumination 22 are turned off. When the SOC is lower than the SOC threshold (SOC ｔｈ２ If the SOC is less than the SOC threshold (SOC), the MCU 30 selects the power saving mode and then executes the control flow of step S4. ｔｈ２ ) or more, the MCU 30 selects the normal mode and then executes the control flow of step S5.

[0028] In step S4, the MCU 30 turns off the IPDs 11 and 12 connected to the meter 21 and the interior illumination 22. In step S5, the MCU 30 turns off the IPDs 13 to 17. In step S6, the MCU 30 specifies the loads to be updated. In this control flow, the loads to be updated are, for example, the HUD 24, the radar 25, and the VDC 26. If there are multiple loads to be updated, the MCU 30 executes the control flow from step S7 to step S9 below in order of the loads with the highest priority for software update.

[0029] In step S7, the MCU 30 turns on the IPD 10 connected to the load to be updated. Since the VDC 26 has the highest priority among the multiple loads to be updated (the HUD 24, the radar 25, and the VDC 26), the MCU 30 first outputs an ON command to the IPD 16.

[0030] In step S8, the MCU 30 sends an active command to the control unit of the VDC 26 to update the software. In step S9, the MCU 30 turns off the IPD 16 upon receiving a software completion command from the VDC 26. In step S10, the MCU 30 determines whether the software update has been completed for all loads to be updated. In this example, because the software for the HUD 24 and the radar 25 has not been updated, the MCU 30 determines that the software update for all loads to be updated has not been completed, and executes the control flow of step S11.

[0031] In step S11, the MCU 30 determines whether the SOC of the battery is equal to the SOC threshold (SOC ｔｈ３ ) or more. ｔｈ３ ) is a threshold value for determining whether to continue the software update. ｔｈ３ ) is set to, for example, 60%. ｔｈ３), the MCU 30 executes the control flow of step S6. In step S6, the MCU 30 designates the load to be updated with the next highest priority. The priority of the radar 25 is higher than the priority of the HUD 24. The MCU 30 starts updating the software of the radar 25.

[0032] The MCU 30 executes the control flow from step S7 to step S10 for the radar 25 and the IPD 15 that have been updated as the loads to be updated, thereby changing the software of the radar 25. After updating the software of the radar 25, if the SOC of the battery is lower than the SOC threshold (SOC ｔｈ３ ), the MCU 30 executes the control flow of step S6. In step S6, the MCU 30 designates the load to be updated with the next highest priority. The MCU 30 starts updating the software of the HUD 24. The MCU 30 executes the control flow of steps S7 to S10 for the HUD 24 and the IPD 14, thereby updating the software of the HUD 24.

[0033] In the control flow of step S10, if it is determined that the software update has been completed for all loads to be updated, or in the control flow of step S11, if the SOC of the battery has reached the SOC threshold (SOC ｔｈ３ ), the MCU 30 notifies the completion of the software update in step S12, and ends the control flow.

[0034] As described above, in the vehicle power supply control device and vehicle power supply control method according to this embodiment, the multiple IPDs 10 and the multiple loads 20 are connected to the power supply line 70 in a one-to-one correspondence, and the MCU 30 controls the on / off of each of the multiple IPDs 10 based on at least one of operation information of an in-vehicle device operated by a user, battery information of the battery, and operation information of the load 20. This makes it possible to reduce power consumption.

[0035] In this embodiment, the MCU 30 controls the load 20 based on at least one of operation information of an in-vehicle device operated by a user, battery information of the battery, and operation information of the load 20. This makes it possible to reduce power consumption.

[0036] In this embodiment, the MCU 30 determines whether the SOC of the battery is equal to the SOC threshold (SOC ｔｈ１ ) or more, the software for controlling the load 20 is updated. This makes it possible to reduce the remaining capacity of the battery.

[0037] In this embodiment, the MCU 30 turns on the IPDs 10 connected to loads 20 that are subject to software updates, among the plurality of loads 20, and turns off the IPDs 10 connected to loads 20 that are not subject to software updates (non-target loads) among the plurality of loads 20. This makes it possible to reduce power consumption.

[0038] In this embodiment, when updating the software, the MCU 30 determines whether the SOC of the battery is equal to or exceeds the SOC threshold (SOC ｔｈ１ ) and is equal to or greater than the SOC threshold (SOC ｔｈ２ ), the IPD 10 connected to the load 20 that has little impact on the user inside the vehicle is turned off. This makes it possible to reduce power consumption.

[0039] As a first modification of this embodiment, when updating software, the MCU 30 may turn off the IPD 10 connected to loads 20 other than the temperature control devices among the multiple loads 20 when the temperature difference between the comfortable interior temperature and the current temperature inside the vehicle is equal to or greater than a predetermined temperature difference threshold. When the temperature difference between the comfortable interior temperature and the current temperature inside the vehicle is large, priority is given to supplying power to temperature control devices such as an air conditioner to increase comfort inside the vehicle. Therefore, the MCU 30 turns off the IPD 10 connected to loads 20 other than the temperature control devices that have a low impact on the user inside the vehicle. This makes it possible to reduce power consumption while maintaining a comfortable interior.

[0040] As a second modification of this embodiment, the MCU 30 may select which elements to turn on and which elements to turn off among the multiple IPDs 10 connected to loads that are not subject to software updates, depending on whether or not a user is present in the vehicle. For example, when the vehicle is stopped and no user is in the vehicle, the MCU 30 turns off the meter 21 and the interior illumination 22. This reduces power consumption.

[0041] In a third modification of this embodiment, when updating software, the MCU 30 selects which elements to turn on and which elements to turn off from among the multiple IPDs 10 connected to loads not subject to the software update, depending on the user's riding position. For example, when the vehicle is stopped and no user is riding in the rear seat, the MCU 30 turns off the IPDs 10 connected to the displays for passengers in the rear seat. This reduces power consumption.

[0042] The IPDs 11 to 17 correspond to the "semiconductor switching elements" of the present invention, the MCU 30 corresponds to the "controller" of the present invention, and the SOC threshold (SOC ｔｈ１ ) corresponds to the first SOC threshold, and the SOC threshold (SOC ｔｈ２ ) corresponds to the second SOC threshold.

[0043] REFERENCE SIGNS LIST 10 IPD 20 Load 30 MCU 31 IPD control unit 32 Software update unit 60 Power supply 70 Power supply line 100 Vehicle power supply system

Claims

1. A vehicle power supply control device comprising: a plurality of loads that operate using power supplied from a power source; a plurality of semiconductor switching elements that are provided on a power supply line that electrically connects the power source and the loads and that connect or disconnect the power source and the loads; and a controller that controls the on / off of the semiconductor switching elements, wherein the plurality of semiconductor switching elements and the plurality of loads correspond one-to-one, and the controller controls the on / off of each of the plurality of semiconductor switching elements based on at least one of information selected from the group consisting of operation information of an in-vehicle device operated by a user, battery information of a battery, and operation information of the loads.

2. A vehicle power supply control device according to claim 1, wherein the controller controls the load connected to the semiconductor switching element based on at least one of the operation information, the battery information, and the operation information.

3. A vehicle power supply control device according to claim 1 or 2, wherein the controller updates software for controlling the load when the SOC of the battery is equal to or higher than a predetermined first SOC threshold.

4. A vehicle power supply control device according to claim 3, wherein the controller turns on the semiconductor switching elements connected to loads among the plurality of loads that are subject to the software update, and turns off the semiconductor switching elements connected to loads among the plurality of loads that are not subject to the software update.

5. A vehicle power supply control device as described in claim 4, wherein the controller, when updating the software, turns off the semiconductor switching element connected to the non-target load that has little impact on users inside the vehicle when the SOC of the battery is equal to or greater than the first SOC threshold and less than the second SOC threshold.

6. A vehicle power supply control device as described in claim 4, wherein the controller turns off the semiconductor switching elements connected to loads other than the temperature control equipment among the plurality of loads when the temperature difference between the comfortable temperature inside the vehicle cabin and the current temperature inside the vehicle cabin is equal to or greater than a predetermined temperature difference threshold when updating the software.

7. A vehicle power supply control device according to claim 4, wherein the controller, when updating the software, selects which of the plurality of semiconductor switching elements connected to the non-target load to turn on and which to turn off depending on whether or not a user is present in the vehicle.

8. A vehicle power supply control device as described in claim 7, wherein the controller, when updating the software, selects which of the multiple semiconductor switching elements connected to the non-target load to turn on and which to turn off depending on the user's riding position.

9. A control method for a vehicle power supply control device mounted on a vehicle, the vehicle power supply control device comprising: a plurality of loads that operate using power supplied from a power source; a plurality of semiconductor switching elements that are provided on power supply lines that electrically connect the power source and the loads and that connect or disconnect the power source and the loads; and a controller that controls the on / off of the semiconductor switching elements, wherein the plurality of semiconductor switching elements and the plurality of loads correspond one-to-one, and the controller controls the on / off of each of the plurality of semiconductor switching elements based on at least one of information selected from operation information of an in-vehicle device operated by a user, battery information of a battery, and operation information of the loads.

Images