JP2022063249A - Power supply control unit and power supply control method - Google Patents

Abstract

To provide a power supply control unit and a power supply control method, capable of highly accurately detecting a system failure.SOLUTION: A power supply control unit according to an embodiment includes a first system, a second system, a system switch and a control part. The first system includes a first battery and supplies power from the first battery to a load. The second system includes a second battery and supplies power from the second battery to the load. The system switch switches the first system and the second system. The control part controls to shut off the system switch if an over current is detected in the first system or the second system. The control part corrects a threshold for detecting the over current depending on the condition of the first battery or the second battery.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power supply control device and a power supply control method.

Conventionally, for example, a technique of a redundant power supply having two power supply systems has been proposed in consideration of power failure during automatic operation (see, for example, Patent Document 1). In this type of technique, when the current value flowing through each system becomes equal to or higher than a predetermined threshold value, power is supplied from the other system by disconnecting one of the failed systems.

Japanese Unexamined Patent Publication No. 2017-61240

However, in the prior art, there is room for improvement in that the system failure is detected with high accuracy.

The present invention has been made in view of the above, and an object of the present invention is to provide a power supply control device and a power supply control method capable of detecting a system failure with high accuracy.

In order to solve the above-mentioned problems and achieve the object, the power supply control device according to the present invention includes a first system, a second system, a system switch, and a control unit. The first system includes a first battery and supplies power to the load from the first battery. The second system includes a second battery, and powers the load from the second battery. The system switch connects and disconnects the first system and the second system. The control unit controls to shut off the system switch when an overcurrent is detected in the first system or the second system. The control unit corrects the threshold value for detecting the overcurrent according to the state of the first battery or the second battery.

According to the present invention, system failure can be detected with high accuracy.

FIG. 1 is a diagram showing a configuration example of a power supply control device according to an embodiment. FIG. 2 is a diagram showing a configuration example of the power supply control device according to the embodiment. FIG. 3 is a diagram showing a configuration example of the power supply control device according to the embodiment. FIG. 4 is a diagram illustrating a method for correcting the current threshold value. FIG. 5 is a diagram illustrating a power supply control device 1 according to the first modification. FIG. 6 is a diagram illustrating a power supply control device 1 according to a second modification. FIG. 7 is a diagram illustrating a method of correcting the voltage threshold value. FIG. 8 is a diagram illustrating a power supply control device 1 according to a third modification.

Hereinafter, embodiments of the power supply control device and the power supply control method disclosed in the present application will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

First, a configuration example of the power supply control device according to the embodiment will be described with reference to FIGS. 1 to 3. 1 to 3 are diagrams showing a configuration example of the power supply control device according to the embodiment. The power supply control device 1 according to the embodiment is a device mounted on a vehicle, and executes the power supply control method according to the embodiment.

As shown in FIG. 1, the power supply control device 1 according to the embodiment is connected to the first load 100 and the second load 200, and supplies electric power to the first load 100 and the second load 200, respectively.

The first load 100 is, for example, a load related to the forward or backward movement of the vehicle and a load not related to the traveling (forward / backward movement, turning and stopping) of the vehicle. The load related to forward movement or reverse movement is, for example, an engine ECU (Electronic Control Unit), a transmission ECU, or the like. The load not related to traveling is, for example, an air conditioner, a wiper, a power window, or the like.

The second load 200 is a load related to bending, stopping, and automatic driving of the vehicle. The load related to the bending is, for example, EPS (Electric Power Steering). The load related to the stop is, for example, a brake ECU. The load related to automatic driving is, for example, a radar, a camera, or the like.

The second load 200 includes a load capable of performing FOP (Fail Operational) running such as evacuation running when the vehicle loses power.

The power supply control device 1 according to the embodiment includes a control unit 2, a high-voltage battery 3, a DCDC converter 4, PbB5, LiB6, diodes 7,8, a system switch SW1, and a battery switch SW2.

Here, the power supply control device 1 includes, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, an input / output port, and various circuits.

The CPU of the computer functions as the control unit 2 by reading and executing the program stored in the ROM, for example.

Further, at least one or all of the functions of the control unit 2 may be configured by hardware such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

Further, the power supply control device 1 has a storage unit (not shown), and the storage unit corresponds to a RAM or a flash memory. The RAM and the flash memory can store information of various programs and the like. The power supply control device 1 may acquire the above-mentioned program and various information via another computer or a portable recording medium connected by a wired or wireless network.

The high-voltage battery 3 is a secondary battery that supplies electric power to the first load 100 and the second load 200. The high-voltage battery 3 is a battery having a higher voltage value than PbB5 and LiB6 described later. The high-voltage battery 3 is an example of the first battery together with PbB5 described later.

The DCDC converter 4 steps down the voltage of the high-voltage battery 3 according to the required voltage of the first load 100 or the second load 200.

PbB5 is a lead storage battery and supplies electric power to the first load 100 and the second load 200. As described above, PbB5 is an example of the first battery. The LiB6 is a lithium-ion battery, and supplies electric power to the second load 200 when the power supply of the first system, which will be described later, fails. LiB6 is an example of a second battery.

Diodes 7 and 8 are diodes for preventing backflow. Specifically, in the diode 7, the cathode is connected to the second load 200, and the anode is connected to the DCDC converter 4 and the PbB5. In the diode 8, the cathode is connected to the second load 200, and the anode is connected to the system switch SW1 and the battery switch SW2.

Further, in the following, the system for supplying power from the high-voltage battery 3 and PbB5 to the first load 100 and the second load 200 will be referred to as a first system, and the path for supplying power from LiB6 to the second load 200 will be referred to as a second system. Refer to.

Further, as shown in FIG. 1, a current sensor S1 is provided in the first system, and a current sensor S2 is provided in the second system. The control unit 2, which will be described later, determines whether or not a power failure has occurred in each of the first system and the second system based on the current values detected by the current sensors S1 and S2.

The system switch SW1 is a switch that disconnects the first system and the second system. The system switch SW1 disconnects the first system and the second system by shutting off when a power failure occurs in the first system or the second system.

The battery switch SW2 is a switch that cuts off and connects LiB6 and the second system. The battery switch SW2 is connected when the power supply of the first system fails so that power is supplied from the LiB 6 to the second load 200.

Here, an operation example of the power supply control device 1 will be described with reference to FIGS. 1 to 3. FIG. 1 shows a normal state, that is, a case where a power failure has not occurred in the first system and the second system, FIG. 2 shows a case where a power failure has occurred in the first system, and FIG. 3 shows a case where a power failure has occurred in the first system. , The case where the power supply failure occurs in the second system is shown. The power failure here refers to a power failure due to the occurrence of a ground fault in the system.

First, an operation example of the power supply control device 1 in a normal state will be described with reference to FIG. As shown in FIG. 1, the control unit 2 of the power supply control device 1 connects the system switch SW1 and shuts off the battery switch SW2 when it is normal. The normal state means that the current values of the current sensor S1 and the current sensor S2 are less than a predetermined current threshold value.

As a result, in the normal state, electric power is supplied from the high-voltage battery 3 and PbB5 to the first load 100 and the second load 200, respectively, via the first system. Further, electric power is supplied from the high-voltage battery 3 and PbB5 to the second load 200 via the second system.

Next, an operation example of the power supply control device 1 when the power supply of the first system fails will be described with reference to FIG. When the control unit 2 of the power supply control device 1 detects an overcurrent in the first system, the control unit 2 shuts off the system switch SW1 and connects the battery switch SW2. The case where the overcurrent is detected in the first system is the case where the current value of the current sensor S1 is equal to or more than the predetermined current threshold value and the current value of the current sensor S2 is less than the predetermined current threshold value.

As a result, when the power supply of the first system fails, the first system can be disconnected from the second load 200 and the LiB6 can be connected to the second load 200 to supply power from the LiB6 to the second load 200. 2 FOP running such as evacuation running with a load of 200 can be performed.

Next, an operation example of the power supply control device 1 when the power supply of the second system fails will be described with reference to FIG. When the control unit 2 of the power supply control device 1 detects an overcurrent in the second system, both the system switch SW1 and the battery switch SW2 are shut off. The case where the overcurrent is detected in the second system is the case where the current value of the current sensor S1 is equal to or higher than the predetermined current threshold value and the current value of the current sensor S2 is equal to or higher than the predetermined current threshold value.

As a result, when the power supply of the second system fails, the second load 200 can be disconnected from the LiB6, and by shutting off the system switch SW1, the backflow from the LiB6 to the first system side can be avoided with high accuracy. can do. Further, by shutting off the system switch SW1, electric power is supplied from the high-voltage battery 3 and PbB5 to the first load 100 and the second load 200 via the first system.

When the power supply of the second system fails, normal running is possible by supplying power to each of the first load 100 and the second load 200, but since the power supply redundancy is lost, the evacuation running is possible. It is preferable to shift to FOP running such as.

Here, in the power supply control method according to the embodiment, the current threshold value at the time of detecting the overcurrent from the current values of the current sensors S1 and S2 is corrected according to the state of the first battery or the second battery.

That is, in the power supply control method according to the embodiment, the current threshold value is corrected according to the state of at least one of the high-voltage batteries 3, PbB5, and LiB6. This point will be described with reference to FIG.

FIG. 4 is a diagram illustrating a method for correcting the current threshold value. As shown in FIG. 4, a reference threshold value is preset for the current threshold value. The control unit 2 corrects by increasing / decreasing the reference threshold value according to the state of the first battery or the second battery.

In the example shown in FIG. 4, as the state of the battery, the temperature of the battery, the remaining charge, the aged deterioration of the battery, and the presence or absence of abnormality of the DCDC converter 4 are shown.

As shown in FIG. 4, the control unit 2 corrects the reference threshold value to be higher when the battery temperature is higher than the reference value, and corrects the reference threshold value to be lower when the battery temperature is lower than the reference value. do. This is because the lower the temperature of the battery, the smaller the current that can be output from the battery.

Further, as shown in FIG. 4, the control unit 2 corrects the reference threshold value to be higher when the remaining charge amount is larger than the reference value, and when the remaining charge amount is less than the reference value, the reference threshold value is set. Is corrected to be low. This is because the smaller the remaining charge, the smaller the current that can be output by the battery.

Further, as shown in FIG. 4, the control unit 2 corrects the reference threshold value to be higher when the aging deterioration of the battery is less than the standard, and when the aging deterioration of the battery is more than the standard, the control unit 2 corrects it. Correct the reference threshold so that it is low. This is because the more the deterioration over time (the more), the smaller the current that can be output by the battery.

Further, as shown in FIG. 4, the control unit 2 corrects the reference threshold value to be high when there is no abnormality in the DCDC converter 4, and lowers the reference threshold value when the DCDC converter 4 has an abnormality. Correct to be. This is because when the DCDC converter 4 is stopped due to an abnormality, the power supply from the high-voltage battery 3 is cut off.

As described above, in the power supply control method according to the embodiment, the overcurrent due to the ground fault of the first system and the second system is corrected by correcting the current threshold value (reference threshold value) according to the state of the first battery or the second battery. Can be detected with high accuracy. That is, according to the power supply control method according to the embodiment, the system failure can be detected with high accuracy.

Further, the control unit 2 corrects the current threshold value according to the battery temperature, the remaining charge, the aged deterioration of the battery, and the presence or absence of an abnormality in the DCDC converter 4, so that the system fails with higher accuracy. Can be detected.

In the example shown in FIG. 4, the case where the reference threshold value is increased or decreased according to the state of the battery is shown, but for example, the current threshold value may be corrected by using a model learned by machine learning. Specifically, the correction value is determined by inputting the battery state into the model obtained by executing machine learning with the battery state as the explanatory variable and the correction value from the reference threshold as the objective variable. May be.

Further, the control unit 2 may apply the corrected current threshold value to each of the two current sensors S1 and S2 as it is, or may make the corrected current threshold values different for each of the two current sensors S1 and S2 based on the corrected current threshold value.

Specifically, the control unit 2 makes the current threshold value of the current sensor S2 arranged on the far side smaller than the current threshold value of the current sensor S1 arranged on the side closer to the first battery (high pressure battery 3 and PbB5). You may.

This is because when a current flows from the first battery (high pressure battery 3 and PbB5) to the second load 200, the current is diverted to the first load 100 and the like, so that the current value of the current sensor S2 is the current of the current sensor S1. This is because it is smaller than the value.

How much the current threshold of the current sensor S2 is made smaller than the current threshold of the current sensor S1 exists, for example, between the path length between the current sensor S1 and the current sensor S2 and between the current sensor S1 and the current sensor S2. It is preferable to determine the resistance according to the type, number, and resistance value of the resistance.

Further, the control unit 2 may measure the inrush current generated at the start of the vehicle as the state of the battery and correct the current threshold value according to the inrush current. Specifically, the control unit 2 measures the inrush current when the accessory power supply or the ignition key is turned on by the current sensors S1 and S2, and corrects the inrush current to a value higher than the measured inrush current. As a result, it is possible to avoid erroneous detection that a system failure has occurred due to the inrush current with high accuracy.

The control unit 2 may correct the current threshold value according to the measurement result of one inrush current, but may correct the current threshold value according to the measurement result of a plurality of inrush currents in the past, for example. .. In such a case, the current threshold value is corrected to a value higher than the average value of the inrush current or the maximum value of the inrush current a plurality of times in the past.

Further, the control unit 2 gives a simulated high load control instruction to the load (first load 100 and second load 200) while parking, and sets the current value flowing during the high load control to the current sensors S1 and S2. Measure with, and correct the current threshold according to the measured current value. The high load control refers to the control in which the power consumption in the load is equal to or higher than a predetermined value.

The control unit 2 corrects the current threshold value to a value higher than the current value detected by the current sensors S1 and S2 during the high load control. As a result, it is possible to avoid erroneous detection that a system failure has occurred when high load control is performed in an actual driving scene with high accuracy.

The control unit 2 may correct the current threshold value according to the measurement result during one high load control. For example, the control unit 2 corrects the current threshold value according to the measurement result during the past multiple high load control. You may. In such a case, the current threshold value is corrected to a value higher than the average value during high load control or the maximum value during high load control a plurality of times in the past.

Further, in the above, the control unit 2 shows the case where the inrush current is measured at the time of starting the vehicle, but the pseudo inrush current can be measured even after the vehicle is started. This point will be described with reference to FIG.

(First modification)
FIG. 5 is a diagram illustrating a power supply control device 1 according to the first modification. As shown in FIG. 5, in the power supply control device 1 according to the modified example, the first load switch SW3 that connects and disconnects the first load 100 from the first system and the second load switch 200 that connects and disconnects the second load 200 from the first system. It is further equipped with a load switch SW4.

The control unit 2 measures the current value flowing at the time of connection by the current sensor S1 by connecting after shutting off the first load switch SW3 and the second load switch SW4 while parking, and the current threshold value according to the measured current value. To correct.

That is, the control unit 2 pseudo-creates the state at the time of starting the vehicle and generates an inrush current by connecting after shutting off the first load switch SW3 and the second load switch SW4. As a result, the frequency and frequency of measurement of the inrush current can be increased, so that the correction accuracy of the current threshold value can be improved.

As described above, the power supply control device 1 according to the embodiment includes a first system, a second system, a system switch SW1, and a control unit 2. The first system includes a first battery (high voltage battery 3 and PbB5), and powers the load (first load 100 and second load 200) from the first battery. The second system includes a second battery (LiB6), and powers the load (second load 200) from the second battery. The system switch SW1 connects and disconnects the first system and the second system. The control unit 2 controls to shut off the system switch SW1 when an overcurrent is detected in the first system or the second system. The control unit 2 corrects the threshold value for detecting the overcurrent according to the state of the first battery or the second battery. As a result, the system failure can be detected with high accuracy.

In the above, the control unit 2 has shown the case where the overcurrent is detected as a power failure, but the voltage drop may be detected as a power failure. That is, when a ground fault occurs as a power failure, an overcurrent is generated toward the ground fault point, but at the same time, a sudden voltage drop occurs. Therefore, the ground fault can be detected not by the overcurrent but by the voltage drop. This point will be described with reference to FIG.

(Second modification)
FIG. 6 is a diagram illustrating a power supply control device 1 according to a second modification. As shown in FIG. 6, the power supply control device 1 according to the second modification has voltage sensors V1 and V2 in place of the current sensors S1 and S2 in FIG. The voltage sensor V1 is provided in the first system and detects the voltage of the first system. The voltage sensor V2 is provided in the second system and detects the voltage of the second system.

When a ground fault occurs in the first system or the second system, the voltage detected by the voltage sensor V1 or the voltage sensor V2 decreases. The control unit 2 compares the voltage value detected by the voltage sensor V2 with the voltage threshold value, and if the voltage value becomes equal to or less than the voltage threshold value, provisionally determines that a ground fault has occurred in the first system or the second system, and determines that a ground fault has occurred, and the system switch. Shut off SW1 and connect the battery switch SW2.

As a result, if a ground fault occurs in the first system, the detected voltage of the voltage sensor V1 continues to be in a state of being equal to or lower than the voltage threshold value, and the detected voltage of the voltage sensor V2 is recovered to be equal to or higher than the voltage threshold value. After shutting off the system switch SW1, the control unit 2 keeps the state where the detection voltage of the voltage sensor V1 is equal to or less than the voltage threshold for a predetermined time or more, and if the detection voltage of the voltage sensor V2 is recovered to the voltage threshold or more. It is determined that a ground fault has occurred in the first system, and the system switch SW1 is shut off and the battery switch SW2 is connected.

As a result, when the power supply of the first system fails (at the time of a ground fault), the first system is disconnected from the second load 200 and the LiB6 is connected to the second load 200 to change the LiB6 to the second load 200. Since electric power can be supplied, FOP running such as evacuation running by the second load 200 can be performed.

If a ground fault has occurred in the second system, the control unit 2 shuts off the system switch SW1 and connects the battery switch SW2, the detected voltage of the voltage sensor V2 continues to be below the voltage threshold, and the voltage sensor. The detected voltage of V1 recovers to the voltage threshold value or higher. After shutting off the system switch SW1, the control unit 2 keeps the state where the detection voltage of the voltage sensor V2 is equal to or less than the voltage threshold for a predetermined time or more, and if the detection voltage of the voltage sensor V1 is recovered to the voltage threshold or more. It is determined that a ground fault has occurred in the second system, and the system switch SW1 is shut off and the battery switch SW2 is shut off.

As a result, when the power supply of the second system fails (at the time of a ground fault), the second load 200 can be disconnected from the LiB6, and by shutting off the system switch SW1, the LiB6 flows back to the first system side. This can be avoided with high accuracy. Further, by shutting off the system switch SW1, electric power is supplied from the high-voltage battery 3 and PbB5 to the first load 100 and the second load 200 via the first system.

Here, in the power supply control method according to the second modification, the voltage threshold value when detecting a low voltage from the voltage values of the voltage sensors V1 and V2 is corrected according to the state of the first battery or the second battery.

That is, in the power supply control method according to the second modification, the voltage threshold value is corrected according to the state of at least one of the high-voltage batteries 3, PbB5, and LiB6. This point will be described with reference to FIG. 7.

FIG. 7 is a diagram illustrating a method of correcting the voltage threshold value. As shown in FIG. 7, the reference threshold value is preset as the voltage threshold value. The control unit 2 corrects by increasing / decreasing the reference threshold value according to the state of the first battery or the second battery. Similar to the current threshold correction method shown in FIG. 4, the correction method employs the battery temperature, the remaining charge, the aged deterioration of the battery, and the presence or absence of an abnormality in the DCDC converter 4 as the state of the battery, and determines the current threshold. Correct in the same way as the correction method.

As described above, in the power supply control method according to the second modification, the voltage threshold value (reference threshold value) is corrected according to the state of the first battery or the second battery, so that the ground fault of the first system and the second system It is possible to detect the low voltage due to high accuracy. That is, according to the power supply control method according to the embodiment, the system failure can be detected with high accuracy.

Further, the control unit 2 corrects the voltage threshold according to the battery temperature, the remaining charge, the aged deterioration of the battery, and the presence or absence of an abnormality in the DCDC converter 4, so that the system fails with higher accuracy. Can be detected.

The control unit 2 may apply the corrected voltage threshold value to each of the two voltage sensors V1 and V2 as it is, or may make the two voltage sensors V1 and V2 different based on the corrected voltage threshold value.

Specifically, the control unit 2 makes the voltage threshold of the voltage sensor V2 arranged on the far side smaller than the voltage threshold of the voltage sensor V1 arranged on the side closer to the first battery (high voltage battery 3 and PbB5). You may.

This is because when a current flows from the first battery (high voltage battery 3 and PbB5) to the second load 200, the voltage value of the voltage sensor V2 becomes smaller due to the loss due to the resistance than the voltage value of the voltage sensor V1. be.

How much the voltage threshold of the voltage sensor V2 is made smaller than the voltage threshold of the voltage sensor V1 exists, for example, between the path length between the voltage sensor V1 and the voltage sensor V2 and between the voltage sensor V1 and the voltage sensor V2. It is preferable to determine according to the type, number, and resistance value of the resistance to be applied.

Further, the control unit 2 may measure the amount of voltage drop generated at the time of starting the vehicle as the state of the battery, and may correct the voltage threshold value according to the amount of voltage drop at the time of starting. Specifically, the control unit 2 measures the voltage drop amount when the accessory power supply or the ignition key is turned on by the voltage sensors V1 and V2, and corrects the voltage threshold value to a value lower than the measured voltage drop amount. .. As a result, it is possible to avoid erroneous detection that a system failure has occurred due to a voltage drop with high accuracy.

The control unit 2 may correct the voltage threshold value according to the measurement result of the voltage drop amount at the time of one start, but for example, according to the measurement result of the voltage drop amount at the time of a plurality of startups in the past. The voltage threshold may be corrected. In such a case, the voltage threshold value is corrected to a value lower than the average value of the amount of voltage drop or the maximum value of the amount of voltage drop a plurality of times in the past.

Further, the control unit 2 gives a simulated high load control instruction to the load (first load 100 and second load 200) during parking, and sets the voltage value that drops during the high load control to the voltage sensor V1. It is measured by V2, and the voltage threshold value is corrected according to the measured voltage value. The high load control refers to the control in which the power consumption in the load is equal to or higher than a predetermined value.

The control unit 2 corrects the voltage threshold value to a value lower than the voltage value detected by the voltage sensors V1 and V2 during the high load control. As a result, it is possible to avoid erroneous detection that a system failure has occurred when high load control is performed in an actual driving scene with high accuracy.

The control unit 2 may correct the voltage threshold value according to the measurement result during one high load control. For example, the control unit 2 corrects the voltage threshold value according to the measurement result during the past multiple high load control. You may. In such a case, the voltage threshold value is corrected to a value lower than the average value during high load control or the maximum value during high load control a plurality of times in the past.

Further, in the above, the control unit 2 shows the case where the voltage drop amount is measured at the time of starting the vehicle, but the pseudo voltage drop amount can be measured even after the vehicle is started. This point will be described with reference to FIG.

(Third modification example)
FIG. 8 is a diagram illustrating a power supply control device 1 according to a third modification. As shown in FIG. 8, the power supply control device 1 according to the third modification has the current sensors S1 and S2 replaced with the voltage sensors V1 and V2 in FIG. 5, and the other configurations are the same as those in FIG. be.

The control unit 2 measures the voltage value that drops at the time of connection by connecting after shutting off the first load switch SW3 and the second load switch SW4 while parking, and the voltage value according to the measured voltage value. Correct the threshold.

That is, by connecting the control unit 2 after shutting off the first load switch SW3 and the second load switch SW4, a state at the time of starting the vehicle is simulated and a voltage drop is generated. As a result, the frequency and frequency of measurement of the voltage drop amount can be increased, so that the correction accuracy of the voltage threshold value can be improved.

(Fourth modification)
In the above, the control unit 2 has shown the case where the overcurrent or the voltage drop is detected as the power failure, but the overvoltage may be detected as the power failure. The DCDC converter 4 steps down the voltage of the high-voltage battery 3, but when an abnormality occurs in the DCDC converter 4, the DCDC converter 4 cannot step down and outputs the voltage of the high-voltage battery 3 as it is, or outputs the voltage of the high-voltage battery 3 as it is. It may be over-boosted and output. That is, when the voltage of the first system or the second system becomes an overvoltage state equal to or higher than the overvoltage threshold value, it indicates that an abnormality has occurred in the DCDC converter 4. As described above, the fourth modification detects the power failure due to the abnormality of the DCDC converter 4 by detecting the overvoltage. Since the configuration diagram of this fourth modification is the same as that of FIG. 6 and the method of correcting the voltage threshold value is the same as that of FIG. 7, detailed description thereof will be omitted.

In the modified example 4, similarly to the second modified example described above, the voltage threshold is corrected by measuring the amount of voltage decrease generated when the vehicle is started, and the measured value of the voltage decreased by simulated high load control during parking is used. Corresponding voltage threshold correction is also applicable.

Further, in the modified example 4, the same voltage threshold correction as in the third modified example described above can be applied.

(Fifth variant)
In the above, the control unit 2 is designed to shut off the battery switch SW2 at the normal time, but as a fifth modification, the battery switch SW2 may be connected at the normal time. In this case, since power is normally supplied to the first load 100 and the second load 200 from both the first battery and the second battery, a temporary abnormality such as a momentary interruption occurs in either battery. However, it is possible to stably supply electric power to the first load 100 and the second load 200.

In the fifth modification, the current threshold value and the voltage threshold value are corrected according to the state of the battery having the higher voltage of the first battery and the second battery. This also makes it possible to detect the system failure with high accuracy.

In addition, the above-described embodiment and modification may be combined as appropriate. For example, the current sensor S1 and the voltage sensor V1 may be arranged in the first system, and the current sensor S2 and the voltage sensor V2 may be arranged in the second system.

In such a case, the control unit 2 corrects the threshold value (current threshold value or voltage threshold value) according to the current value of the current sensors S1 and S2 or the voltage value of the voltage sensors V1 and V2.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments described and described above. Thus, various modifications can be made without departing from the spirit or scope of the overall concept of the invention as defined by the appended claims and their equivalents.

1 Power supply control device 2 Control unit 3 High-voltage battery 4 DCDC converter 5 PbB
6 LiB
7, 8 Diode 100 1st load 200 2nd load S1, S2 Current sensor SW1 System switch SW2 Battery switch SW3 1st load switch SW4 2nd load switch V1, V2 Voltage sensor

Claims (11)

A first system that includes a first battery and supplies power to the load from the first battery,
A second system that includes a second battery and supplies power from the second battery to the load, and
A system switch that connects and disconnects the first system and the second system,
A control unit that controls to shut off the system switch when an overcurrent is detected in the first system or the second system.
Equipped with
The control unit
A power supply control device comprising correcting a threshold value for detecting an overcurrent according to the state of the first battery or the second battery. A first system that includes a first battery and supplies power to the load from the first battery,
A second system that includes a second battery and supplies power from the second battery to the load, and
A system switch that connects and disconnects the first system and the second system,
A control unit that controls to shut off the system switch when a power failure is detected in the first system or the second system.
Equipped with
The control unit
A power supply control device comprising correcting a threshold value for detecting a power failure according to the state of the first battery or the second battery. The power failure is an overcurrent and
The control unit
The power supply control device according to claim 2, wherein the threshold value for detecting the overcurrent is corrected according to the state of the first battery or the second battery. The power failure is a voltage drop,
The control unit
The power supply control device according to claim 2 or 3, wherein the threshold value for detecting the voltage drop is corrected according to the state of the first battery or the second battery. The power failure is an overvoltage and is
The control unit
The power supply control device according to any one of claims 2 to 4, wherein the threshold value for detecting the overvoltage is corrected according to the state of the first battery or the second battery. The state of the first battery or the second battery is
The power supply control device according to any one of claims 1 to 5, further comprising at least one of battery temperature, remaining charge, and aging. The first battery is
A high-voltage battery that supplies power to the load by stepping down by a DCDC converter is included.
The control unit
The power supply control device according to any one of claims 1 to 6, wherein the threshold value is corrected according to the presence or absence of an abnormality in the DCDC converter. The control unit
The claim is characterized in that, as the state of the first battery or the second battery, the inrush current or the amount of voltage decrease generated at the time of starting the vehicle is measured, and the threshold value is corrected according to the inrush current or the amount of voltage decrease. The power supply control device according to any one of 1 to 7. The control unit
While parking, a simulated high load control instruction is given to the load, the current value flowing during the high load control, or the voltage value of the first system or the second system is measured, and the current value or the current value or The power supply control device according to any one of claims 1 to 8, wherein the threshold value is corrected according to the voltage value. A load switch for connecting and disconnecting the load from the first system is further provided.
The control unit
By connecting after shutting off the load switch while parking, the current value flowing at the time of connection or the voltage value of the first system or the second system is measured, and the threshold value is measured according to the current value or the voltage value. The power supply control device according to any one of claims 1 to 9, wherein the power supply is corrected. A first system that includes a first battery and supplies power to the load from the first battery,
A second system that includes a second battery and supplies power from the second battery to the load, and
A system switch that connects and disconnects the first system and the second system,
A power control method performed by a power control unit equipped with
A control step of controlling to shut off the system switch when a power failure is detected in the first system or the second system is included.
The control step is
A power supply control method comprising correcting a threshold value for detecting a power failure according to the state of the first battery or the second battery.

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