Power control device, control method and storage medium

Abstract

This disclosure relates to a power control device, control method, and storage medium. A power control device for a vehicle is provided. The power control device is an apparatus for controlling the supply of power from a second power supply source, which is provided as a backup for a first power supply source, to multiple loads. The power control device includes: a switching unit that switches between the first mode and the second mode, in which power from the second power supply source is supplied to a first load but not to a second load, and in the second mode, the power from the second power supply source is supplied to the second load but not to the first load; and a control unit that controls the mode switching of the switching unit based on the state of the vehicle.

Description

Technical Field

[0001] This disclosure relates to vehicle power control devices, etc., that control the power supply from a power source to multiple loads. Background Technology

[0002] Japanese Unexamined Patent Application Publication No. 2018-182935 (JP 2018-182935 A) discloses a power supply system that uses an energy storage element made of a capacitor as a backup to the main power supply source, so as to perform a backup power supply from the energy storage element to the load in the event of a power failure such as a voltage drop in the main power supply source. Summary of the Invention

[0003] When multiple loads require backup power simultaneously, the inrush currents consumed by the actuators (ACTs) designed for these loads may overlap. If this overlap results in a large current flowing through the power supply line, a momentary voltage drop can occur due to the parasitic resistance of capacitors and wiring resistance, potentially hindering the operation of the backup power supply.

[0004] This disclosure is made in view of the above-mentioned problems, and the purpose of this disclosure is to provide a power control device, etc., which can suppress the overlap of inrush current consumed by the load in the backup power supply.

[0005] To address the aforementioned problems, one solution of this disclosure is a power control device for a vehicle. The power control device controls the supply of power from a second power source, which is provided as a backup for a first power source, to multiple loads. The power control device includes: a switching unit that switches between a first mode and a second mode, in which power from the second power source is supplied to a first load but not to a second load, and in the second mode, power from the second power source is supplied to the second load but not to the first load; and a control unit that controls the mode switching of the switching unit based on the state of the vehicle.

[0006] According to the power control device disclosed herein, since the power supply to the first load and the power supply to the second load do not occur simultaneously, the overlap of inrush currents consumed by multiple loads can be suppressed in the standby power supply using the power from the second power supply source. Attached Figure Description

[0007] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and wherein:

[0008] Figure 1This is a functional block diagram of a power control device and its peripheral components according to embodiments of the present disclosure;

[0009] Figure 2 It is a flowchart of the power supply control process executed by the power control device; and

[0010] Figure 3 It is a flowchart of the power supply control process executed by the power control device. Detailed Implementation

[0011] In the vehicle power control device according to this disclosure, when the main power supply fails and it is necessary to use a redundant power supply to provide backup power for the door unlocking system and the braking system, the inrush current generated by the operation of the door unlocking actuator and the inrush current generated by the operation of the braking actuator will not overlap. This prevents a momentary drop in the output voltage due to the discharge of a large current from the redundant power supply.

[0012] In the following, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

[0013] Example

[0014] Configuration

[0015] Figure 1 This is a functional block diagram of a power control device 100 and its peripheral components according to an embodiment of the present disclosure. Figure 1 The functional block shown includes a power control unit 100, multiple systems including an SBW system 210, a door unlocking system 220, and a braking system 230, and a first power supply source 300. The power control unit 100, SBW system 210, door unlocking system 220, braking system 230, and first power supply source 300 are mounted on the vehicle.

[0016] The first power supply source 300 is the main power source (+B power source) that supplies power to the SBW system 210, the door unlocking system 220, and the braking system 230. Examples of predetermined power supply configurations for the first power supply source 300 include an AC generator that generates electricity and a DC-DC converter that converts the generated electricity into a predetermined voltage, or a rechargeable secondary battery (auxiliary battery) such as a lead-acid battery.

[0017] Systems such as the SBW system 210, door unlocking system 220, and braking system 230 are on-board devices (on-board loads) for implementing predetermined functions related to the vehicle, and in particular require redundant power supply configurations. These systems are all connected and configured to receive a primary power supply (not shown) from a first power supply source 300 in the absence of a power control device 100, and to receive a backup power supply from the power control device 100 based on the first power supply source 300. Systems installed on the vehicle are not limited to… Figure 1 The system shown.

[0018] SBW system 210 is a shift-by-wire (SBW) control device that allows the gear stages in a transmission (not shown) to be changed via electrical signals. SBW system 210 includes SBW_ECU 212, which is an electronic control unit that converts the driver's shifting operation into an electrical signal, and SBW_ACT 211, which is an actuator that changes the gear stages based on the electrical signals indicated by SBW_ECU 212. In SBW_ACT 211, for example, when a door is opened, a load current is generated at the moment when control is executed to place the shift position in the parking position.

[0019] The door unlocking system 220 is a locking / unlocking control device that can lock / unlock vehicle doors using electrical signals. The door unlocking system 220 includes a door unlocking ECU 222 and a door unlocking ACT 221. The door unlocking ECU 222 is an electronic control unit that converts the driver's locking / unlocking operation into an electrical signal. The door unlocking ACT 221 is an actuator that changes the locked and unlocked states of the vehicle doors based on the electrical signals indicated by the door unlocking ECU 222. In the door unlocking ACT 221, for example, a load current is generated after a predetermined time (e.g., 10 seconds) has elapsed since the vehicle collision.

[0020] Braking system 230 is a braking control device capable of generating braking force on a vehicle. Braking system 230 includes a braking ECU 232 and a braking ACT 231. The braking ECU 232 is an electronic control unit that converts the driver's braking operation into an electrical signal, and the braking ACT 231 is an actuator that generates braking force based on the electrical signal indicated by the braking ECU 232. In braking ACT 231, for example, after a mains power failure, a load current is generated when the driver inputs a braking operation.

[0021] The power control device 100 is a sub-power source (redundant power source). When the power supply from the first power supply source 300 to the SBW system 210, the door unlocking system 220 and the braking system 230 is abnormal due to a power failure of the first power supply source 300, it is used to perform backup power supply to the SBW system 210, the door unlocking system 220 and the braking system 230.

[0022] Figure 1 The power control device 100 shown includes a second power supply 110, a charging / discharging circuit 120, a detection unit 130, a switching unit 140, a control unit 150, and multiple relays 161 to 165.

[0023] The second power supply source 110 is, for example, a rechargeable secondary battery, such as a lithium-ion battery, or an energy storage element such as a capacitor. The second power supply source 110 is configured as a backup for the first power supply source 300. The second power supply source 110 is connected to the charging / discharging circuit 120 so as to charge the power of the first power supply source 300 and discharge the power stored therein to the SBW system 210, the door unlocking system 220, and the braking system 230.

[0024] The charging / discharging circuit 120 is used to input power from the first power supply source 300 via relay 161 and output power to the second power supply source 110. Furthermore, the charging / discharging circuit 120 is also used to input power from the second power supply source 110 and output power to the SBW system 210, the door unlocking system 220, and the braking system 230 via relays 162 to 165 and the switching unit 140. For example, a DC / DC converter can be used in the charging / discharging circuit 120. The charging / discharging circuit 120 can charge / discharge the second power supply source 110 based on instructions from the control unit 150, etc.

[0025] The detection unit 130 is configured to detect predetermined states of the vehicle. The detection unit 130 detects an abnormality (e.g., a power failure) in the first power supply source 300 as a predetermined state of the vehicle (first detection unit). Furthermore, the detection unit 130 detects a state where the vehicle has been involved in a collision or where the vehicle's speed has decreased as a predetermined state of the vehicle (second detection unit). When the detection unit 130 detects a predetermined state of the vehicle, it notifies the control unit 150.

[0026] The switching unit 140 is configured to switch the power supply state from a first power supply source 300 or a second power supply source 110 to door unlocking ACT 221 and braking ACT 231. The switching unit 140 has a "first mode" and a "second mode," where the "first mode" is a state in which power from the second power supply source 110 is supplied to braking ACT 231 (first load) but not to door unlocking ACT 221 (second load), and the "second mode" is a state in which power from the second power supply source 110 is supplied to door unlocking ACT 221 (second load) but not to braking ACT 231 (first load). The switching unit 140 can selectively switch between the first mode and the second mode based on instructions from the control unit 150. The switching unit 140 can be configured by inserting a relay capable of switching between electrical on / off states between charging / discharging circuit 120 and braking ACT 231 (first relay) and between charging / discharging circuit 120 and door unlocking ACT 221 (second relay).

[0027] The control unit 150 is configured, for example, to control mode switching for switching the power supply state (first mode or second mode) in the switching unit 140 based on the vehicle state detected by the detection unit 130. The control unit 150 can also control the state of the charging / discharging circuit 120. Furthermore, the control unit 150 can control the on / off states of a plurality of relays 161 to 165. Details of the control performed by the control unit 150 will be described later.

[0028] Multiple relays 161 to 165 are switching elements that can be switched between an on / off electrical state based on instructions from the control unit 150, etc. One terminal of relay 161 is connected to the first power supply 300, and the other terminal is connected to the charging / discharging circuit 120. One terminal of relay 162 is connected to the charging / discharging circuit 120, and the other terminal is connected to SBW_ACT 211. One terminal of relay 163 is connected to the charging / discharging circuit 120, and the other terminal is connected to SBW_ECU 212. One terminal of relay 164 is connected to the charging / discharging circuit 120, and the other terminal is connected to the door unlocking ECU 222. One terminal of relay 165 is connected to the charging / discharging circuit 120, and the other terminal is connected to the braking ECU 232. The number of relays 161 to 165 is not limited. Figure 1 The quantity shown is increased or decreased depending on the number of systems connected to the power control device 100.

[0029] The power control device 100 described above can typically be configured as an electronic control unit (ECU) including a processor, memory, input / output interfaces, etc. When the processor reads and executes the program stored in the memory, the ECU performs some or all of the functions of the charging / discharging circuit 120, detection unit 130, switching unit 140, and control unit 150 described above.

[0030] control

[0031] Next, further reference Figure 2 The control performed by the power control device 100 will be described. Figure 2 This is a flowchart illustrating the power supply control process performed by the various components of the power control device 100. For example, when the vehicle's ignition is turned on (IG-ON), the process begins... Figure 2 The power supply control shown.

[0032] Step S201

[0033] The power control device 100 completes the necessary charging of the second power supply source 110. With this charging complete, in the event of an anomaly in the first power supply source 300, the second power supply source 110 can be used to provide backup power to the SBW system 210, the door unlocking system 220, and the braking system 230. When the charging of the second power supply source 110 is complete, the process proceeds to step S202.

[0034] Step S202

[0035] The power control device 100 determines whether the detection unit 130 has detected an abnormality in the first power supply source 300. An abnormality in the first power supply source 300 is a state where power cannot be supplied from the first power supply source 300 to the SBW system 210, the door unlocking system 220, and the braking system 230, such as a power failure or a grounding failure. When an abnormality is detected in the first power supply source 300 (step S202: Yes), the process proceeds to step S203, and when no abnormality is detected in the first power supply source 300 (step S202: No), the power supply control ends.

[0036] Step S203

[0037] The power control unit 100 controls the backup power supply status to the SBW system 210, door unlocking system 220, and braking system 230 via the switching unit 140 and the control unit 150. Specifically, the power control unit 100 controls each of SBW_ACT 211, SBW_ECU 212, door unlocking ECU 222, braking ACT 231, and braking ECU 232 to enable power supply (on state), and controls only door unlocking ACT 221 to be in a state where power cannot be supplied (off state). That is, the switching unit 140 switches to the first mode.

[0038] The reason for selecting the first mode when an anomaly occurs in the first power supply source 300 is that the vehicle may be in motion when the anomaly occurs, and in this case, a rapid response to the driver's braking operation should be prioritized over the door unlocking operation. This is achieved by setting a state that allows power to be supplied to the first mode; for example, even if both braking and door unlocking operations are input simultaneously, only the braking operation is accepted, and the inrush currents of the two operations do not overlap. When the system's backup power supply state is controlled to the first mode, the process proceeds to step S204.

[0039] Step S204

[0040] The power control device 100 determines whether the detection unit 130 has detected a vehicle collision. A vehicle collision may be a rear-end collision or contact with an object such as a vehicle in front, an oncoming vehicle, a traffic light, or a guardrail. When a vehicle collision is detected (step S204: Yes), the process proceeds to step S205; and when no vehicle collision is detected (step S204: No), the process proceeds to step S207.

[0041] Step S205

[0042] The power control unit 100 controls the backup power supply status to the SBW system 210, door unlocking system 220, and braking system 230 via the switching unit 140 and the control unit 150. Specifically, the power control unit 100 controls SBW_ACT 211, SBW_ECU 212, door unlocking ACT 221, door unlocking ECU 222, and braking ECU 232 to enable power supply (conducting state), and controls only the braking ACT 231 to be in a state where power cannot be supplied (disconnected state). That is, the switching unit 140 switches to the second mode.

[0043] The reason for setting the second mode in the event of a vehicle collision following an anomaly in the first power supply source 300 is that, due to the collision, the vehicle speed has become extremely low or the vehicle has likely come to a complete stop, and in this situation, the likelihood of the driver operating the brakes is low; unlocking the doors to escape should be the priority. This is achieved by setting a state where power can be supplied to the second mode; for example, even if both braking and door unlocking operations are input simultaneously, only the door unlocking operation is accepted, and the inrush currents of the two operations do not overlap. When the backup power supply state to the system is controlled to the second mode, the process proceeds to step S206.

[0044] Step S206

[0045] The power control unit 100 supplies backup power from the second power supply source 110 to the door unlocking system 220. At this time, backup power is also supplied from the second power supply source 110 to the SBW system 210 and the brake ECU 232. When the backup power supply to the door unlocking system 220 is executed, the power supply control ends.

[0046] Step S207

[0047] The power control unit 100 supplies backup power from the second power supply source 110 to the braking system 230. At this time, backup power is also supplied from the second power supply source 110 to the SBW system 210 and the door unlocking ECU 222. When the backup power supply to the braking system 230 is executed, the power supply control ends.

[0048] It should be noted that SBW_ACT 211 or other actuators can be used instead of door unlocking ACT 221 as actuators for controlling the backup power supply status. In this case, control can be achieved by switching the switching sequence between the first and second modes, which switch based on vehicle collision detection.

[0049] Modified Example

[0050] Figure 3 This is a flowchart illustrating the power supply control process according to a modified example executed by the various components of the power control device 100. Figure 3 The power supply control in the modified example shown is replaced by the processing in step S304. Figure 2 The processing of step S204. Other processing in the power supply control of this modified example is the same as... Figure 2 The processing is the same as that in power supply control, so some descriptions will be omitted.

[0051] When the backup power supply status of the SBW system 210, the door unlocking system 220 and the braking system 230 is controlled to the first mode in step S203, the process proceeds to step S304.

[0052] Step S304

[0053] The power control device 100 determines whether the detection unit 130 has detected that the vehicle speed has decreased to a value equal to or less than a predetermined value. This determination is synonymous with the determination of a vehicle collision, so the predetermined value can be set to the smallest possible value (e.g., less than 5 km / h) assuming that the vehicle speed will decrease due to a vehicle collision. When the vehicle speed is detected to have become equal to or less than the predetermined value (step S304: Yes), the process proceeds to step S205, and when the vehicle speed is not detected to have become equal to or less than the predetermined value (step S304: No), the process proceeds to step S207.

[0054] In step S205, the backup power supply status to the SBW system 210, door unlocking system 220, and braking system 230 is controlled to a second mode. The reason for setting the second mode when the vehicle speed decreases after an anomaly occurs in the first power supply source 300 is that, in the case of the aforementioned vehicle collision, when the vehicle speed has become extremely low or the vehicle has come to a stop, the driver is unlikely to operate the brakes, and unlocking the doors to escape should be the priority.

[0055] Operation and Effect

[0056] As described above, in the power control device 100 according to an embodiment of the present disclosure, when power is supplied to the SBW system 210, the door unlocking system 220 and the braking system 230 from the backup second power supply source 110 (redundant power source) which is the first power supply source 300 (main power source), based on the determination of a vehicle collision or the determination of a reduction in vehicle speed, only one of the door unlocking ACT 221 and the braking ACT 231 is controlled to a state in which the backup power is not supplied.

[0057] This control ensures that even if the driver simultaneously instructs on both braking and door unlocking, only the braking or door unlocking operation will be accepted. Therefore, the inrush current caused by braking and the inrush current caused by door unlocking do not overlap, preventing discharge from the second power supply source 110. Consequently, sudden and significant drops in the output voltage of the second power supply source 110 can be suppressed, and operations that interfere with the backup power supply from the second power supply source 110 (such as resetting the control microcomputer) are avoided.

[0058] Furthermore, since there is no need to increase the capacity of the capacitors, etc., used as the second power supply source 110, it is possible to prevent an increase in the cost, weight, and size of the power control device 100. In addition, there is no need to take measures such as pre-setting the output voltage of the second power supply source 110 to a high level to prepare for voltage drops, and the degradation of the lifespan of capacitors, etc., can be suppressed.

[0059] Although one embodiment of the technology disclosed herein has been described above, this disclosure can be interpreted, in addition to a power control device, as a method performed by a power control device, a program of the method, a computer-readable non-transitory storage medium storing the program, and a vehicle including a power control device.

[0060] The power control device disclosed herein can be used as a backup integrated power supply for a vehicle having an energy storage unit that supplies backup power to multiple systems (loads) such as SBW / door unlocking / braking.

Claims

1. A power control device for a vehicle, the power control device being a means of controlling the power supply from a second power supply source provided as a backup for a first power supply source to a plurality of loads, the power control device comprising: A switching unit that switches between a first mode and a second mode, wherein in the first mode, power from the second power supply source is supplied to the first load but not to the second load, and in the second mode, power from the second power supply source is supplied to the second load but not to the first load. A control unit that controls the mode switching of the switching unit based on the state of the vehicle; A first detection unit detects an anomaly in the first power supply source, wherein when the anomaly is detected in the first power supply source, the control unit switches the switching unit to the first mode; and The second detection unit detects the occurrence of a collision of the vehicle as the state of the vehicle, wherein when the abnormality of the first power supply source is detected and the collision of the vehicle is detected during the power supply in the first mode, the control unit switches the switching unit to the second mode.

2. The power control device according to claim 1 further includes a second detection unit, which detects the speed of the vehicle as the state of the vehicle, wherein, When the abnormality of the first power supply source is detected and the speed of the vehicle is detected to be equal to or less than a predetermined value during the power supply in the first mode, the control unit switches the switching unit to the second mode.

3. The power control device according to claim 1, wherein, The switching unit includes a first relay disposed between the second power supply source and the first load, and a second relay disposed between the second power supply source and the second load. The control unit controls the on and off states of the first and second relays.

4. The power control device according to any one of claims 1 to 3, wherein, The first load is a brake actuator, and the second load is a door unlocking actuator.

5. A control method executed by a power control device for a vehicle, the power control device being an apparatus for controlling the supply of power from a second power supply source provided as a backup for a first power supply source to a plurality of loads, the control method comprising: Steps for detecting anomalies in the first power supply source; The step of detecting the occurrence of a collision of the vehicle as the state of the vehicle; When an anomaly is detected in the first power supply source, the step of switching to the first mode is performed, in which power from the second power supply source is supplied to the first load but not to the second load. as well as When the anomaly of the first power supply source is detected and the collision of the vehicle is detected during power supply in the first mode, the step of switching from the first mode to the second mode is that, in the second mode, the power from the second power supply source is supplied to the second load instead of the first load.

6. A storage medium storing a control program that causes a computer of a power control device for a vehicle to perform the following steps, the power control device being a means of controlling the supply of power from a second power source provided as a backup for a first power supply source to a plurality of loads: Steps for detecting anomalies in the first power supply source; The step of detecting the occurrence of a collision of the vehicle as the state of the vehicle; When an anomaly is detected in the first power supply source, the step of switching to the first mode is performed, in which power from the second power supply source is supplied to the first load but not to the second load. as well as When the anomaly of the first power supply source is detected and the collision of the vehicle is detected during power supply in the first mode, the step of switching from the first mode to the second mode is that, in the second mode, the power from the second power supply source is supplied to the second load instead of the first load.

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