JP2023120665A - On-vehicle power supply control device - Google Patents

Abstract

To provide an on-vehicle system including a power conversion unit that may convert power from a high-voltage battery, power being supplied to a low-voltage load using the high-voltage battery even if power supply from the power conversion unit is at a stop.SOLUTION: An on-vehicle system 2 includes: a power conversion unit 4 that converts power supplied from a high-voltage battery 90 to output power to a conducting path 82; and a deriving unit 60 that derives the power based on the high-voltage battery 90 via a path different from the power conversion unit 4. A power supply control device 10 is used for the on-vehicle system 2. The power supply control device 10 has an adjustment unit 20 that receives the power output to the conducting path 82 from the power conversion unit 4, power from a low-voltage battery 98, and the power from the deriving unit 60. The adjustment unit 20 supplies the power based on the deriving unit 60 to a low-voltage load 88 during a stop in which power supply from the power conversion unit 4 to the conducting path 82 is at a stop.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an in-vehicle power supply control device.

Patent Literature 1 discloses a vehicle power supply circuit that aims to achieve backup power supply to auxiliary equipment without adding a dedicated power supply for backup of the auxiliary equipment. In the power supply circuit for a vehicle disclosed in Patent Document 1, the one of the first secondary battery and the second secondary battery whose output voltage is closer to the output voltage of the low-voltage battery is supplemented without going through the first DCDC converter and the second DCDC converter. connected to the machine.

Japanese Patent Application Laid-Open No. 2020-124060

In the vehicle power supply circuit of Patent Document 1, a part of the high-voltage battery is directly connected to the auxiliary equipment, and the part that distributes and adjusts the power from the DCDC converter, the low-voltage battery, and the high-voltage battery is auxiliary. Not provided outside the machine.

The present disclosure supplies power to a low-voltage load using a high-voltage battery in an in-vehicle system including a power conversion unit capable of converting power from a high-voltage battery, even when the power supply from the power conversion unit is stopped. provide the technology to obtain

An in-vehicle power supply control device, which is one of the present disclosure,
An in-vehicle power supply control device used in an in-vehicle system having a high-voltage battery and a low-voltage battery that is a supply source for supplying power to a low-voltage load and has an output voltage lower than that of the high-voltage battery,
The in-vehicle system includes a power conversion unit that converts power supplied from the high-voltage battery and outputs the power to a conductive path, and a derivation unit that derives the power based on the high-voltage battery through a path different from the power conversion unit. and a system comprising
an adjustment unit to which power output from the power conversion unit to the conductive path, power from the low-voltage battery, and power from the derivation unit are input;
The adjustment unit supplies power based on the lead-out unit to the low-voltage load during a stop in which power supply from the power conversion unit to the conducting path is stopped.

The technology according to the present disclosure is an in-vehicle system that includes a power converter that can convert power from a high-voltage battery. can supply

FIG. 1 is a block diagram schematically illustrating an in-vehicle system including an in-vehicle power supply control device according to the first embodiment. FIG. 2 is a block diagram specifically exemplifying the adjustment unit and the like in the power supply control device disclosed in FIG. FIG. 3 is a block diagram specifically exemplifying the selector and the like in the power supply control device disclosed in FIG. FIG. 4 is a flowchart illustrating the flow of control performed by the in-vehicle system of FIG. 1;

Embodiments of the present disclosure are listed and illustrated below. It should be noted that the features exemplified below may be combined in any way without contradiction.

[1] An in-vehicle power supply control device used in an in-vehicle system having a high-voltage battery and a low-voltage battery that is a supply source for supplying power to a low-voltage load and has an output voltage lower than that of the high-voltage battery. hand,
The in-vehicle system includes a power conversion unit that converts power supplied from the high-voltage battery and outputs the power to a conductive path, and a derivation unit that derives the power based on the high-voltage battery through a path different from the power conversion unit. and a system comprising
an adjustment unit to which power output from the power conversion unit to the conductive path, power from the low-voltage battery, and power from the derivation unit are input;
An in-vehicle power supply control device, wherein the adjustment unit supplies power based on the derivation unit to the low-voltage load while power supply from the power conversion unit to the conduction path is stopped.

The power supply control device of [1] above can supply power to the low-voltage battery using the power of the high-voltage battery even when the power supply from the power conversion unit is stopped. In addition, the adjustment unit can input and adjust the power output from the power conversion unit to the conducting path, the power from the low-voltage battery, and the power from the derivation unit.

[2] The adjustment unit has a voltage conversion circuit that steps up or steps down an input voltage based on the power from the derivation unit to generate an output voltage directed to the low-voltage load. and the voltage conversion circuit, which supplies power to the low-voltage load to the power supply control device for vehicle according to [1].

The power supply control device of [2] above reduces or boosts the input voltage based on the derivation unit when using the power of the high-voltage battery through a path other than the power conversion unit while the power conversion unit is stopped. can be used.

[3] The in-vehicle power supply control device according to [2], wherein the adjustment unit supplies both the power from the low-voltage battery and the power from the voltage conversion circuit to the low-voltage load during the stop.

The power supply control device of [3] above can prevent the power from being used only by the low-voltage battery or only by the high-voltage battery while the power conversion unit is stopped.

[4] The adjustment unit includes a supply path through which power is supplied from the low-voltage battery and supplies power to the low-voltage load, and a control unit that controls the voltage conversion circuit. have
The voltage conversion circuit outputs a voltage to the supply path,
The control unit controls the voltage conversion circuit so that the voltage applied by the low-voltage battery to the supply path and the voltage applied by the voltage conversion circuit to the supply path are brought closer to each other during the suspension. in-vehicle power supply controller.

The power supply control device of [4] above can match the output of the voltage conversion circuit to the same level as that of the low-voltage battery while the power conversion unit is stopped, so that the power can be easily supplied from both in a well-balanced manner.

[5] The on-vehicle power supply according to [3], wherein the adjustment unit switches the power supplied to the low-voltage load during the stop between the power from the low-voltage battery and the power from the voltage conversion circuit. Control device.

The power supply control device of [5] above can suppress, with a simpler method, the power being used while the power conversion unit is stopped being biased toward only one of the low-voltage battery and the high-voltage battery.

[6] having a selection unit that selects a power supply source from among a plurality of candidate parts in the high-voltage battery;
The in-vehicle power supply control device according to any one of [1] to [5], wherein the derivation unit derives power from the power supply source selected by the selection unit.

The power supply control device of [6] above does not always use only a specific portion of the high-voltage battery, but can be used by selecting from among a plurality of candidate portions, thereby suppressing biased use portions. be able to.

[7] The selection unit selects a site with the highest SOH (State Of Health) as the candidate site from among sites having a SOC (State Of Charge) greater than or equal to a threshold value among the plurality of candidate sites. 6].

The power supply control device of [7] above suppresses the selection of a portion with a low SOC and preferentially uses a portion with a high SOH when using a high-voltage battery while the power conversion unit is stopped. can be done.

[8] The adjustment unit includes a first input path through which power is input from the power conversion unit, a second input path through which power is input from the low-voltage battery, and the first input path. an output path electrically connected to both the input path and the second input path;
The first input path is provided with a first fuse that can cut off the first input path,
The second input path is provided with a second fuse that can cut off the second input path,
Furthermore, it has an accommodating body which accommodates said 1st input path, said 2nd input path, said output path, said 1st fuse, and said 2nd fuse. Automotive power supply controller.

The power supply control device of [8] above utilizes a high-voltage battery in a unit containing a first input path, a second input path, an output path, a first fuse, and a second fuse in the housing body. The ability to supply power to low voltage loads can be added.

[9] The adjustment unit has a detection unit that detects a supply suppression state in which power is not normally supplied from either the power conversion unit or the low-voltage battery, and the supply suppression state is detected by the detection unit. The on-vehicle power supply control device according to any one of [1] to [8], wherein the power based on the lead-out portion is supplied to the low-voltage load when the power is supplied to the low-voltage load.

The power supply control device of [9] above can supply power to the low-voltage load even when sufficient power is not supplied from the power conversion unit and the low-voltage battery. The "supply suppression state in which power is not normally supplied" may be, for example, a state in which neither the power conversion unit nor the low-voltage battery supplies a DC voltage exceeding the threshold, and neither the power conversion unit nor the low-voltage battery A state in which DC power exceeding the threshold is not supplied, or a state in which the output of both the power conversion unit and the low-voltage battery is stopped may be used.

<First Embodiment>

1. Overview of In-Vehicle System 2 FIG. 1 shows an in-vehicle system 2 including an in-vehicle power supply control device 10 according to the first embodiment. In the following description, the in-vehicle power supply control device 10 is also referred to as the power supply control device 10 . The in-vehicle system 2 is a system mounted on a vehicle (not shown), and is a system capable of supplying power to various loads. The vehicle on which the in-vehicle system 2 is mounted is, for example, an electric vehicle, a plug-in hybrid vehicle, a hybrid vehicle, or other types of vehicle.

As shown in FIG. 1, the in-vehicle system 2 includes a high-voltage battery 90, a low-voltage battery 98, a high-voltage load 80, a low-voltage load 88, a power converter 4, a power supply control device 10, and the like.

The high voltage battery 90 is a battery capable of supplying high voltage to the high voltage load 80 . High-voltage battery 90 may be configured by a secondary battery such as a lithium ion battery, or may be configured by another type of storage battery. High-voltage battery 90 applies a predetermined high voltage (for example, approximately 400 V) between power paths 86A and 86B when fully charged. The output voltage applied across power paths 86A and 86B when high-voltage battery 90 is fully charged is higher than the output voltage when low-voltage battery 98 is fully charged (the voltage of conductive path 84 relative to the ground potential).

The power supplied from the high-voltage battery to the power paths 86A, 86B can be supplied to a drive motor (not shown) via an inverter (not shown). Note that FIG. 1 omits a configuration for supplying power from power paths 86A and 86B to the inverter. A high voltage battery 90 is a source of power for a drive motor (not shown), and specifically, the inverter may operate to produce three-phase AC power for driving the drive motor. The drive motor is a device that generates drive force for rotating the wheels of the vehicle (vehicle on which the in-vehicle system 2 is mounted) based on the power supplied from the high-voltage battery 90 .

The low-voltage battery 98 may be composed of a secondary battery such as a lead-acid battery, or may be composed of another type of storage battery. The low-voltage battery 98 applies a predetermined low voltage (for example, 12V) to the conducting path 84 when fully charged. The output voltage applied to the conductive path 84 by the low voltage battery 98 is the potential difference between the conductive path 84 and ground (not shown in FIG. 1). Low voltage battery 98 is a source that can power low voltage load 88 . The output voltage when the low-voltage battery 98 is fully charged is lower than the output voltage when the high-voltage battery 90 is fully charged. While the vehicle is running, the output voltage of the high voltage battery 90 is maintained higher than the output voltage of the low voltage battery 98 .

A low voltage load 88 is a load to which a low voltage is applied. The low-voltage load 88 may be, for example, a starter motor, an alternator, a radiator cooling fan, etc., an electric power steering system, an electric parking brake, lighting, a wiper drive unit, a navigation device, etc., or other devices. may

A high voltage load 80 is a load to which a high voltage is applied. The high-voltage load 80 may be, for example, an air conditioner, a heater, or other load.

Power paths 86A and 86B are paths for transmitting power between high voltage battery 90 and power converter 4 . One power path 86A of power paths 86A and 86B functions as a high-potential power path and forms a conductive path between the high-potential electrode of high-voltage battery 90 and one end of power converter 4. FIG. The other power path 86B of the power paths 86A and 86B forms a conductive path between the low-potential side electrode of the high-voltage battery 90 and the other end of the power converter 4 . In the example of FIG. 1, when both the relays 85A and 85B are in the ON state, a DC voltage is applied between the power paths 86A and 86B, and power can be transmitted through the power paths 86A and 86B. Become.

The relays 85A and 85B are relays that switch between a cutoff state that cuts off conduction in the power paths 86A and 86B and a canceled state that cancels the cutoff state. When the relays 85A and 85B are both off, energization through the relays 85A and 85B is interrupted in both directions, and when both the relays 85A and 85B are on, energization through the relays 85A and 85B is interrupted. Allowed in both directions.

The power conversion unit 4 is configured by, for example, a DCDC converter such as an insulated DCDC converter. The power conversion unit 4 has a function of converting power supplied from the high-voltage battery 90 through the power paths 86A and 86B and outputting the power to the conduction path 82 . Specifically, the power conversion unit 4 uses the DC voltage applied between the power paths 86A and 86B as an input voltage, steps down the input voltage, and applies an output voltage to the conduction path 82. can do When the power converter 4 performs the step-down operation, the step-down operation is performed to output a DC voltage so as to adjust the voltage between the conducting path 82 and the ground (not shown in FIG. 1) to the target voltage. The power converter 4 uses the voltage applied to the conductive path 82 (the voltage between the conductive path 82 and the ground) as an input voltage, boosts this input voltage, and generates a DC voltage between the power paths 86A and 86B. It may have a function of performing a boosting operation so as to apply voltage.

2. Basic Configuration of Power Supply Control Device 10 The power supply control device 10 is used in the in-vehicle system 2, and constitutes a part of the in-vehicle system 2 in the example of FIG. The power supply control device 10 includes an adjustment section 20, a derivation section 60, a monitoring section 68, and the like.

The derivation unit 60 is a part that derives the power based on the high-voltage battery 90 through a path different from that of the power conversion unit 4 . The derivation unit 60 mainly includes a selection unit 61 and a conductive path 62 and functions to derive power from the power supply source selected by the selection unit 61 . Conductive path 62 is a conductive path electrically connected to voltage conversion circuit 22 . Conductive path 63 is a conductive path electrically connected to ground. In the example of FIG. 2 , the voltage applied across conductive paths 62 and 63 is the input voltage to voltage conversion circuit 22 .

Selection unit 61 has a function of selecting a power supply source from among a plurality of candidate parts in high-voltage battery 90 . In the example of FIG. 1, candidate parts 92A, 92B, 92C, and 92D are illustrated as a plurality of candidate parts. It may operate to draw power from and not draw power from other candidate sites. All of the candidate parts 92A, 92B, 92C, and 92D are parts that function as batteries.

As shown in FIG. 3 , the selection unit 61 has a switching unit 100 and a control device 65 . The switching unit 100 switches between an energized state in which the conductive paths 62 and 63 and a portion of the high voltage battery 90 are short-circuited and a cutoff state in which the conductive paths 62 and 63 and the high voltage battery 90 are disconnected. In the example of FIG. 3, the switching section 100 has switches 101A, 101B, 102A, 102B, 103A, 103B, 104A and 104B. One end of the switch 101A and the high potential side electrode of the candidate portion 92A are short-circuited by a conductive path 71A. A position P1 is a position where the conductive path 71A is connected. One end of the switch 101B and the low-potential-side electrode of the candidate portion 92A are short-circuited by a conductive path 71B. A position P2 is a position where the conductive path 71B is connected. One end of the switch 102A and the high potential side electrode of the candidate portion 92B are short-circuited by the conductive path 72A. A position P3 is a position where the conductive path 72A is connected. One end of the switch 102B and the electrode on the low potential side of the candidate portion 92B are short-circuited by the conductive path 72B. A position P4 is a position where the conductive path 72B is connected. One end of the switch 103A and the high potential side electrode of the candidate portion 92C are short-circuited by a conductive path 73A. A position P5 is a position where the conductive path 73A is connected. One end of the switch 103B and the low-potential-side electrode of the candidate portion 92C are short-circuited by a conductive path 73B. A position P6 is a position where the conductive path 73B is connected. One end of the switch 104A and the high potential side electrode of the candidate portion 92D are short-circuited by the conductive path 74A. A position P7 is a position where the conductive path 74A is connected. One end of the switch 104B and the electrode on the low potential side of the candidate site 92D are short-circuited by the conductive path 74B. A position P8 is a position where the conductive path 74B is connected.

For example, in the switching unit 100, the switches 101A and 101B are turned on, and the switches 102A, 102B, 103A, 103B, 104A, and 104B are turned off. The conductive path 62 is short-circuited, and the electrode with the lowest potential among the candidate parts 92A and the conductive path 63 are short-circuited. By selecting the candidate site 92A in this manner, a voltage corresponding to the potential difference between both ends of the candidate site 92A is applied to the conductive path 62 . Similarly, in the switching unit 100, the switches 102A and 102B are turned on, and the switches 101A, 101B, 103A, 103B, 104A, and 104B are turned off. and the conductive path 62 are short-circuited, and the electrode with the lowest potential among the candidate parts 92B and the conductive path 63 are short-circuited. By selecting the candidate site 92B in this manner, a voltage corresponding to the potential difference between both ends of the candidate site 92B is applied to the conductive path 62 . A control device 65 performs control to turn on/off each of the switches 101A, 101B, 102A, 102B, 103A, 103B, 104A, and 104B. The control device 65 is an information processing device having an information processing function and an arithmetic function, and has, for example, a storage section and a CPU. The control device 65 may be configured as a device different from the control section 28 and may be implemented by the control section 28 .

The adjustment unit 20 outputs power from the power conversion unit 4 to the conductive path 82, power output from the low-voltage battery 98 to the conductive path 84, power supplied from the lead-out unit 60 via the conductive path 62, is input. As shown in FIG. 2, the adjustment unit 20 includes a first input path 31, a second input path 32, a supply path 33, a first fuse 41, a second fuse 42, a first switch 51, a second switch 52, and a voltage conversion circuit. 22, a control unit 28, and the like. The first switch 51 is also referred to as switch 51 . The second switch 52 is also referred to as switch 52 .

The first input path 31 is a conductive path whose one end is electrically connected to the conductive path 82 and is a path to which power from the power converter 4 is input. The first input path 31 short-circuits the supply path 33 and the conductive path 82 when the switch 51 is on.

The second input path 32 is a conductive path whose one end is electrically connected to the conductive path 84 and is a path to which power from the low-voltage battery 98 is input. The second input path 32 short-circuits the supply path 33 and the conductive path 84 when the switch 52 is on.

The first fuse 41 is interposed in the middle of the first input path 31 and has a function of shutting off the energization of the first input path 31 in both directions when an overcurrent occurs in the first input path 31 . The second fuse 42 is interposed in the middle of the second input path 32 and has a function of shutting off the energization of the second input path 32 in both directions when an overcurrent occurs in the second input path 32 . For example, when the first fuse 41 is cut off due to a ground fault occurring in the conductive path 82 , the supply path 33 and the second input path 32 are electrically separated from the conductive path 82 . Further, when the second fuse 42 is cut off due to a ground fault occurring in the conductive path 84 , the supply path 33 and the first input path 31 are electrically separated from the conductive path 84 .

The first switch 51 is interposed in the middle of the first input path 31, permits energization of the first input path 31 when it is turned on, and turns off when it is turned off. The energization of the 1 input path 31 is interrupted in both directions. The second switch 52 is interposed in the middle of the second input path 32, permits energization of the second input path 32 when it is turned on, and turns off when it is turned off. The energization of the two-input path 32 is interrupted in both directions.

The supply path 33 corresponds to an example of an output path. The supply path 33 is electrically connected to the other end of the first input path 31 and the other end of the second input path 32 . The supply path 33 is a path to which power is supplied from the low-voltage battery 98 and is also a path to which power is supplied from the power converter 4 . The supply path 33 is a path that is electrically connected to the low voltage load 88 and supplies power to the low voltage load 88 .

Voltage conversion circuit 22 may operate to step-down or step-up an input voltage based on power from derivation 60 to produce an output voltage for low voltage load 88 . The voltage conversion circuit 22 is configured as a DCDC converter, for example, and can perform a voltage conversion operation to output a DC voltage to the supply path 33 . The voltage conversion circuit 22 steps down the DC voltage applied to the conductive path 62 and applies the DC voltage to the supply path 33 , or steps up the DC voltage applied to the conductive path 62 to supply the DC voltage to the supply path 33 . A voltage boosting operation can be performed.

The control unit 28 is an information processing device having arithmetic functions and information processing functions, and has, for example, a CPU and a storage unit. The control unit 28 has a function of controlling the step-down operation and step-up operation of the voltage conversion circuit 22 . Specifically, the control unit 28 has a function of controlling the step-down operation or step-up operation of the voltage conversion circuit 22 so that the voltage conversion circuit 22 outputs a target voltage to the supply path 33 . The control unit 28 has a function of controlling on/off of the first switch 51 and on/off of the second switch 52 .

As shown in FIG. 2, the adjustment unit 20 includes a first input path 31, a second input path 32, a supply path 33, a first fuse 41, a second fuse 42, a first switch 51, a second switch 52, and a voltage conversion circuit. 22, a housing body 20A housing a control unit 28 and the like. 20 A of containers are comprised by resin or metal cases, for example. In FIG. 2, the container 20A is conceptually indicated by a chain double-dashed line.

Monitoring unit 68 has a function of monitoring a plurality of candidate parts in high-voltage battery 90 . Specifically, the monitoring unit 68 has a function of detecting the SOH (State Of Health) and SOC (State Of Charge) of each of the candidate sites 92A, 92B, 92C, and 92D using a known method. The monitoring unit 68 has a function of communicating with the selecting unit 61, and detects and transmits the SOH and SOC information of each of the candidate parts 92A, 92B, 92C, and 92D periodically or when a predetermined condition is satisfied.

3. Operation of Power Supply Control Device 10 The adjustment unit 20 has a function of supplying power based on the lead-out unit 60 to the low-voltage load 88 while the power supply from the power conversion unit 4 to the conducting path 82 is stopped. Specifically, the adjustment unit 20 supplies power based on at least one of the low-voltage battery 98 and the voltage conversion circuit 22 to the low-voltage load 88 while the power supply from the power conversion unit 4 to the conducting path 82 is stopped. can operate to This operation is performed, for example, according to the flow shown in FIG.

The control of FIG. 4 is performed by the control unit 28 or by the control unit 28 and the control device 65. FIG. Note that the control unit 28 and the control device 65 may be configured by the same device, and in this case, this device may perform the control of FIG.

The control in FIG. 4 is started when a predetermined start condition is satisfied in the device (for example, the control unit 28 and the control device 65) that executes the control in FIG. 4, and is repeatedly executed at short time intervals. The start condition may be the start of power supply to the device that executes the control in FIG. 4, or other conditions.

After starting the control of FIG. 4, the control unit 28 executes the determination of step S1 to determine whether or not the power supply from the low-voltage battery 98 is abnormal. For example, when the voltage applied to the conducting path 84 is less than the threshold, the control unit 28 determines that the power supply from the low-voltage battery 98 is abnormal (Yes in step S1), and advances the process to step S8. The control unit 28 determines that the power supply from the low-voltage battery 98 is not abnormal when the voltage applied to the conducting path 84 is equal to or higher than the threshold (No in step S1), and advances the process to step S2. In step S1, it may be determined that the power supply from the low-voltage battery 98 is abnormal when the voltage applied to the conductive path 84 is less than the threshold when the switch 52 is in the off state. Alternatively, it may be determined that the power supply from the low-voltage battery 98 is abnormal when the voltage of the conductive path 84 while the power conversion unit 4 and the voltage conversion circuit 22 are stopped is less than a threshold. Alternatively, it may be determined that the power supply from the low-voltage battery 98 is abnormal when the low-voltage battery 98 is determined to be malfunctioning by another failure determination method. In a representative example, for example, the control unit 28 has a function of detecting voltage applied to the conductive path 84 and a function of detecting voltage applied to the conductive path 82 .

In step S2, the control unit 28 determines whether or not the power supply from the power conversion unit 4 is abnormal. In step S2, the power supply from the power conversion unit 4 is abnormal when the voltage applied to the conductive path 82 is less than the threshold when the operating condition of the power conversion unit 4 is satisfied and the switch 51 is in the off state. If not, it may be determined that the power supply from the power conversion unit 4 is not abnormal. Alternatively, it may be determined that the power supply from the power conversion unit 4 is abnormal when the output current deviates from the appropriate range during operation of the power conversion unit 4. When it is determined that there is a failure, it may be determined that the power supply from the power conversion unit 4 is abnormal. In any case, if the control unit 28 determines in step S2 that the power supply from the power conversion unit 4 is not abnormal, the process proceeds to step S3, and if it is determined that the power supply is abnormal, the process proceeds to step S4. .

In step S3, the control unit 28 determines whether the power conversion unit 4 is operating normally. Specifically, when the power conversion unit 4 is operating in a state other than the abnormality (abnormality in step S2), the control unit 28 determines Yes in step S3, and advances the process to step S7. When the power conversion unit 4 is not operating, the control unit 28 determines No in step S3, and advances the process to step S4.

If the control unit 28 determines that the power supply from the power conversion unit 4 is abnormal in step S2, or determines that the power conversion unit 4 is not operating in step S3, the low-voltage battery 98 and It operates so as to use two systems of the derivation unit 60 . Specifically, in step S<b>4 , the control unit 28 turns off the switch 51 and turns on the switch 52 to start the operation of the voltage conversion circuit 22 . If the two systems of the low-voltage battery 98 and lead-out unit 60 are already being used at the start of step S4, the control unit 28 maintains that state.

After step S4, the control device 65 performs an operation of selecting a power supply source (step S5). In a representative example, the operation of step S5 is performed after step S4, but the operation of step S5 may be performed before step S4 or may be performed in parallel with step S4.

Every time the control device 65 acquires information on the SOH and SOC of the candidate parts 92A, 92B, 92C, and 92D from the monitoring unit 68, the controller 65 updates the latest SOH and SOC of the candidate parts 92A, 92B, 92C, and 92D to the adjustment unit 20. stored in a storage unit (not shown) provided in the . When the control device 65 selects the power supply source in step S5, the site with the highest latest SOH is selected from among the multiple candidate sites 92A, 92B, 92C, and 92D with the latest SOC equal to or greater than the threshold. The switching unit 100 is switched so as to select it as a candidate part. For example, among the latest SOH of each of the plurality of candidate sites 92A, 92B, 92C, and 92D, when the SOH of the candidate site 92A is the highest and the SOC of the candidate site 92A is equal to or greater than the threshold, the control device 65 selects the candidate site 92A as the power supply source. In this case, the control device 65 turns on the switches 101A and 101B and turns off the switches 102A, 102B, 103A, 103B, 104A and 104B, so that the high potential side electrode and the conductive path of the candidate portion 92A are switched. 62 are short-circuited, and the low-potential-side electrode of the candidate portion 92A and the conductive path 63 are short-circuited. By selecting the candidate site 92A in this way, a voltage corresponding to the potential difference between both ends of the candidate site 92A is applied between the conductive paths 62 and 63. FIG.

After step S5, the control unit 28 performs the process of step S6. In a representative example, the process of step S6 is performed after step S5, but the process of step S6 may be started before step S5 or may be started at the same time as step S5. In step S6, the control unit 28 increases or decreases the DC voltage applied to the conductive path 62 while maintaining the state executed in step S4 (the state in which the switch 51 is turned off and the switch 52 is turned on). Then, the voltage conversion circuit 22 is caused to perform a voltage conversion operation so as to apply a DC voltage to the supply path 33 . For example, the control unit 28 detects the output voltage of the low-voltage battery 98 (for example, the voltage applied to the conductive path 84) before or during the execution of the process of step S6, and sets this output voltage as the target voltage Vt, The voltage conversion circuit 22 is controlled so that the DC voltage applied to the supply path 33 by the voltage conversion circuit 22 becomes the target voltage Vt. The output voltage of the low-voltage battery 98 may be the voltage applied to the conductive path 84 when the switch 52 is in the OFF state, or may be the voltage applied to the conductive path 84 when the power converter 4 and the voltage conversion circuit 22 are not operating. It may be the applied voltage. The detection of the output voltage of the low-voltage battery 98 may be performed periodically, or may be performed each time a predetermined condition is satisfied.

In this way, in step S6 performed while the power conversion unit 4 is stopped, the control unit 28 controls the voltage applied by the low-voltage battery 98 to the supply path 33 (the output voltage of the low-voltage battery 98) while turning off the switch 52. and the voltage applied to the supply path 33 by the voltage conversion circuit 22 are controlled to approach (specifically, to match). By performing such operations, the adjustment unit 20 supplies both the power from the low-voltage battery 98 and the power from the voltage conversion circuit 22 to the low-voltage load 88 while the power conversion unit 4 is stopped. If the voltage conversion circuit 22 has already performed the voltage conversion operation at the start of step S6, the control unit 28 continues the state in which the voltage conversion circuit 22 has performed the voltage conversion operation.

After step S6, the control unit 28 ends the control in FIG. After the control in FIG. 4 ends, the control unit 28 repeats the control in FIG. 4 again.

If the control unit 28 determines in step S3 that the power conversion unit 4 is in operation, it operates to use the two systems of the low-voltage battery 98 and the power conversion unit 4 in step S7. Specifically, both the switches 51 and 52 are turned on, and the operation of the voltage conversion circuit 22 is stopped. In a situation where it is determined as Yes in step S3, the power converter 4 applies a voltage (eg, 14.5V voltage) slightly higher than the output voltage (eg, 12V charge voltage) of the low-voltage battery 98 to the conductive path. 82.

When the control unit 28 determines in step S1 that the power supply from the low-voltage battery 98 is abnormal, in step S8, it determines whether the power supply from the power conversion unit 4 is abnormal. The determination method in step S8 is the same as the determination method in step S2. If the control unit 28 determines in step S8 that the power supply from the power conversion unit 4 is normal, the process proceeds to step S9. In step S9, the control unit 28 operates to use the one system (power conversion unit 4) in which no abnormality has occurred. Specifically, the switch 52 is turned off, the switch 51 is turned on, and the operation of the voltage conversion circuit 22 is stopped.

When the control unit 28 determines in step S8 that the power supply from the power conversion unit 4 is abnormal, the process proceeds to step S10. In step S10, the control unit 28 operates so as to use the derivation unit 60. Specifically, the switches 51 and 52 are turned off, and the voltage conversion circuit 22 starts operating. If only the derivation unit 60 is being used at the start of step S10, the control unit 28 continues its usage state. After step S10, the control device 65 performs the process of step S11. The processing of step S11 is the same as the processing of step S5. In a representative example, the operation of step S11 is performed after step S10, but the operation of step S11 may be performed before step S10 or may be performed in parallel with step S10. After step S11, the control unit 28 performs the process of step S12. The processing of step S12 is similar to that of step S6. In a representative example, the process of step S12 is performed after step S11, but the process of step S12 may be started before step S11 or may be started at the same time as step S11.

4. Example of Effect The power supply control device 10 supplies power to the low-voltage battery 98 using the power of the high-voltage battery 90 even when the power supply from the power converter 4 to the conduction path 82 is stopped. can do. Moreover, the adjustment unit 20 can adjust the power output from the power conversion unit 4 to the conductive path 82, the power from the low-voltage battery 98, and the power from the lead-out unit 60 by inputting them to itself.

Since the power supply control device 10 has the voltage conversion circuit 22, when using the power of the high-voltage battery 90 through a path other than the power conversion unit 4 while the power conversion unit 4 is stopped, the derivation unit 60 can be used by stepping down or stepping up the input voltage based on

Since the power supply control device 10 can supply the power from both the low-voltage battery 98 and the voltage conversion circuit 22 to the low-voltage load 88 while the power converter 4 is stopped, only the low-voltage battery 98 is used during the stop. or only the high-voltage battery 90 can be suppressed.

The adjustment unit 20 may control the voltage conversion circuit 22 so that the voltage applied to the supply path 33 by the low-voltage battery 98 and the voltage applied to the supply path 33 by the voltage conversion circuit 22 are brought closer to each other during the suspension. If the adjustment unit 20 adopts this method, the output of the voltage conversion circuit 22 can be brought close to the output voltage of the low-voltage battery 98 while the power conversion unit 4 is stopped, and the voltage can be easily supplied from both in a well-balanced manner.

When using the power of the high-voltage battery 90 while the power supply from the power conversion unit 4 is stopped, the power supply control device 10 does not always use only a specific portion of the high-voltage battery 90, but uses a plurality of candidate portions. It can be used by selecting from among them. Therefore, the power supply control device 10 can suppress bias in the utilization portion of the high-voltage battery 90 during the suspension.

When using the high-voltage battery 90 while the power conversion unit 4 is stopped, the power supply control device 10 can preferentially use a portion with a high SOH while suppressing selection of a portion with a low SOC.

The power supply control device 10 constitutes a unit that accommodates a first input path 31, a second input path 32, a supply path 33 (output path), a first fuse 41, and a second fuse 42 inside the container 20A. be able to. This unit can then utilize the high voltage battery 90 to power the low voltage load 88 .

In the power supply control device 10, the control unit 28 functions as a detection unit and detects a "supply suppression state in which neither the power conversion unit 4 nor the low-voltage battery 98 supplies a DC voltage exceeding a threshold". Then, in the power supply control device 10 , power based on the lead-out section 60 is supplied to the low-voltage load 88 when the control section 28 (detection section) detects the supply suppression state. Since such operation is performed, power can be supplied to the low-voltage load 88 even when sufficient power is not supplied from the power converter 4 and the low-voltage battery 98 .

<Other embodiments>
The present disclosure is not limited to the embodiments illustrated by the above description and drawings. For example, the features of the embodiments described above or below can be combined in any consistent manner. Also, any feature of the embodiments described above or below may be omitted if not explicitly indicated as essential. Furthermore, the embodiments described above may be modified as follows.

In the above-described embodiment, the supply path 33 and the low-voltage battery 98 are continuously short-circuited during the period in which step S6 is repeatedly executed (the period in which the voltage conversion circuit 22 operates while the operation of the power conversion unit 4 is stopped), Although the voltage conversion circuit 22 operates continuously, it is not limited to this example. For example, the control unit 28 may perform control to switch the power supplied to the low-voltage load 88 between the power from the low-voltage battery 98 and the power from the voltage conversion circuit 22 while the power conversion unit 4 is not operating. good. For example, while the operation of the power conversion unit 4 is stopped, the control unit 28 may control the voltage conversion circuit 22 to apply a voltage higher than the output voltage of the low-voltage battery 98 to the supply path 33 or turn off the switch 52. A first period which is a period during which the voltage conversion circuit 22 performs an operation of applying a voltage to the supply path 33 while keeping the switch 52 in an ON state and a voltage lower than the output voltage of the low-voltage battery 98 is applied to the supply path 33 . or a second period during which the operation of the voltage conversion circuit 22 is stopped while the switch 52 is turned on. In this way, the power supplied to the low voltage load 88 can be switched between the power from the low voltage battery 98 and the power from the voltage conversion circuit 22 . If the adjustment unit 20 adopts the above method, it is possible to suppress the bias of the power used to only one of the low-voltage battery 98 and the high-voltage battery 90 while the power conversion unit 4 is stopped by a simpler method.

Although the power supply control device 10 includes the derivation unit 60 in the above-described embodiment, the power supply control device 10 may not include the derivation unit 60 . That is, the power supply control device 10 may be configured by the adjustment unit 20 .

In the above-described embodiment, the derivation unit 60 is configured to select a portion to be used from a plurality of candidate portions of the high-voltage battery 90, but the derivation unit 60 is configured to use only a specific portion of the high-voltage battery 90. may In other words, only the power of a specific portion of high-voltage battery 90 (for example, candidate portion 92D) may be derived via derivation section 60 .

In the above-described embodiment, four candidate parts 92A, 92B, 92C, and 92D are exemplified as candidate parts that can be selected by the selector 61. However, in the high-voltage battery 90, candidate parts other than these can be further selected. Alternatively, the range of each candidate site may be different from the example in FIG.

Although the four candidate sites 92A, 92B, 92C, and 92D are all connected in series in the above-described embodiment, some may be connected in parallel.

Although the voltage conversion circuit 22 is configured by a DCDC converter in the above-described embodiment, it may be configured by a regulator such as an LDO (Low Drop Out regulator).

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

2: In-vehicle system 4: Power conversion unit 10: Power supply control device 20: Adjustment unit 20A: Housing 22: Voltage conversion circuit 28: Control unit 31: First input path 32: Second input path 33: Supply path 41: First fuse 42 : Second fuse 51 : First switch 52 : Second switch 60 : Derivation part 61 : Selection part 62 : Conductive path 63 : Conductive path 65 : Control device 68 : Monitoring part 71A : Conductive path 71B : Conductive path 72A: Conductive path 72B: Conductive path 73A: Conductive path 73B: Conductive path 74A: Conductive path 74B: Conductive path 80: High voltage load 82: Conductive path 84: Conductive path 85A: Relay 85B: Relay 86A: Power path 86B: Power path 88: Low voltage load 90: High voltage battery 92A: Candidate part 92B: Candidate part 92C: Candidate part 92D: Candidate part 98: Low voltage battery 100: Switching unit 101A: Switch 101B: Switch 102A: Switch 102B: Switch 103A: Switch 103B: Switch 104A: Switch 104B: Switch

Claims (5)

An in-vehicle power supply control device used in an in-vehicle system having a high-voltage battery and a low-voltage battery that is a supply source for supplying power to a low-voltage load and has an output voltage lower than that of the high-voltage battery,
The in-vehicle system includes a power conversion unit that converts power supplied from the high-voltage battery and outputs the power to a conductive path, and a derivation unit that derives the power based on the high-voltage battery through a path different from the power conversion unit. and a system comprising
an adjustment unit to which power output from the power conversion unit to the conductive path, power from the low-voltage battery, and power from the derivation unit are input;
An in-vehicle power supply control device, wherein the adjustment unit supplies power based on the derivation unit to the low-voltage load while power supply from the power conversion unit to the conduction path is stopped. The adjustment unit includes a voltage conversion circuit that steps up or steps down an input voltage based on the power from the derivation unit to generate an output voltage directed to the low-voltage load, and during the stop, the low-voltage battery and the voltage The vehicle-mounted power supply control device according to claim 1, wherein power based on at least one of the conversion circuits is supplied to the low-voltage load. 3. The vehicle-mounted power supply control device according to claim 2, wherein the adjustment unit supplies both the power from the low-voltage battery and the power from the voltage conversion circuit to the low-voltage load during the stop. The adjustment unit includes a supply path through which power is supplied from the low-voltage battery and a path through which power is supplied to the low-voltage load, and a control unit that controls the voltage conversion circuit,
The voltage conversion circuit outputs a voltage to the supply path,
4. The control unit according to claim 3, wherein during the stop, the control unit controls the voltage conversion circuit so that the voltage applied by the low-voltage battery to the supply path and the voltage applied by the voltage conversion circuit to the supply path are brought closer to each other. in-vehicle power supply controller. 4. The vehicle-mounted power supply control device according to claim 3, wherein the adjustment unit switches power supplied to the low-voltage load between power from the low-voltage battery and power from the voltage conversion circuit during the suspension.

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