Control device, control method, and control program

Abstract

To provide a control apparatus capable of appropriately controlling a switch of a relay from a disconnection state to a connection state.SOLUTION: A control apparatus that controls a battery, comprises: an acquisition part that acquires a physical amount of the battery; a detection part that detects a predetermined signal; and a control part that controls a relay provided between the battery and a predetermined device to which power is supplied from the battery on the basis of the physical amount of the battery. In the case where a state that the physical amount of the battery satisfies a predetermined condition is continued for a first time, the control part connects the relay when the relay is disconnected, and makes the first time be different depending on whether or not the predetermined signal has been detected by the detection part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a control device that controls a battery mounted in a vehicle. [Background technology]

[0002] In vehicles that use a lithium-ion battery (LiB) as an auxiliary battery, a method is used in which a relay is used to electrically disconnect the auxiliary battery from the vehicle system in order to ensure the safety of the vehicle system and protect the battery when certain conditions occur.

[0003] When the auxiliary battery is disconnected from the vehicle system, it is necessary to electrically connect the auxiliary battery again in order to start the vehicle. Patent Document 1 discloses a control device that detects the connection of an external power source and switches a relay that disconnects the auxiliary battery from the vehicle system from a disconnected state to a connected state. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-114079 A Summary of the Invention [Problem to be solved by the invention]

[0005] When the output of a power source such as an external charger connected to the vehicle is small, the power required to start the vehicle system may be insufficient, and the system may not be able to start. For this reason, it is necessary to appropriately determine the timing for switching the relay from a disconnected state to a connected state based on the state of the vehicle and the state of the power source such as the external charger, and to control the switching of the relay.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a control device and the like that can appropriately control the switching of a relay from a disconnected state to a connected state. [Means for solving the problem]

[0007] In order to solve the above problems, one aspect of the disclosed technology is a control device that controls a battery, comprising an acquisition unit that acquires physical quantities of the battery, a detection unit that detects a predetermined signal, and a control unit that controls a relay provided between the battery and a predetermined device to which power is supplied from the battery based on the physical quantities of the battery, wherein when the relay is disconnected, if a state in which the physical quantities of the battery satisfy a predetermined condition continues for a first time, the control unit connects the relay and varies the first time depending on whether or not the predetermined signal is detected by the detection unit. Effect of the Invention

[0008] According to the control device of the present disclosure, the first time for determining whether the relay is connected is dynamically changed depending on whether a specified signal is detected or not, so that the switching of the relay from a disconnected state to a connected state can be appropriately controlled according to the vehicle situation. [Brief description of the drawings]

[0009] [Figure 1] A functional block diagram of a control device and its peripheral components according to the present embodiment. [Diagram 2] 1 is a flowchart showing a first example of relay control executed by a control device. [Figure 3A] 2 is a flowchart showing a second example of relay control executed by the control device. [Figure 3B] 2 is a flowchart showing a second example of relay control executed by the control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The control device of the present disclosure determines the vehicle status in which it is desirable to connect the relay or the vehicle status in which the connection of the relay should be prioritized based on information on the battery and the external charger, and switches the relay from a disconnected state to a connected state. This control makes it possible to switch the relay appropriately. Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the drawings.

[0011] <Embodiment> [composition] Fig. 1 is a functional block diagram of a control device 110 and its peripheral parts according to an embodiment of the present disclosure. The functional block illustrated in Fig. 1 includes a battery pack including a battery monitoring ECU 100, a relay 200, and a battery 300, a plurality of devices 410 and 420, and an external charger 500. As an example, this battery pack is used in vehicles such as automobiles that use an internal combustion engine as a power source and hybrid vehicles (HVs) that use an electric motor as a power source.

[0012] Battery 300 is a battery for supplying power to a plurality of devices 410 and 420 via relay 200. Battery 300 is configured by connecting in series a plurality of cells C of a secondary battery such as a lithium ion battery configured to be chargeable and dischargeable. Battery 300 can be used as a so-called auxiliary battery used to supply power to devices not involved in driving the vehicle.

[0013] The relay 200 is a switch provided between the battery 300 and the multiple devices 410 and 420 or the external charger 500. This relay 200 switches between a conductive state (ON) in which terminals are electrically connected, and a non-conductive state (OFF) in which terminals are electrically disconnected, based on the control (instruction) of the battery monitoring ECU 100. An example of the relay 200 is a normally-on single-pole single-throw switch.

[0014] The multiple devices 410 and 420 are predetermined devices connected to the battery 300, and are devices that operate with power supplied from the battery 300 via the relay 200. The number of the multiple devices 410 and 420 is not limited to that shown in Fig. 1. When the battery 300 is used as an auxiliary battery for a vehicle, examples of the multiple devices 410 and 420 can include auxiliary devices such as actuators such as a motor and a solenoid, lights such as headlamps and interior lights, air conditioners such as a heater and a cooler, steering, brakes, and ECUs (Electronic Control Units) for automatic driving and advanced driving assistance.

[0015] The external charger 500 is a predetermined device connected to the battery 300, and is a charger intended to charge the battery 300. The external charger 500 is configured to be attachable and detachable by a vehicle user or the like. The external charger 500 includes not only a charger used in an emergency such as a dead battery, but also a charger used in normal times for the purpose of using the multiple devices 410 and 420. The external charger 500 can be connected to a power supply line connecting the relay 200 and the multiple devices 410 and 420, and can pass a charging current to the battery 300 via the relay 200. A part of the charging current is supplied to the battery monitoring ECU 100 as a power supply, and is also provided for consumption by the multiple devices 410 and 420.

[0016] The battery monitoring ECU 100 monitors and controls the state of the battery 300, and also controls the connection state of the relay 200. The battery monitoring ECU 100 includes a control device 110 including an acquisition unit 111, a detection unit 112, a control unit 113, and a determination unit 114, a voltage measurement unit 120, and a current measurement unit 130.

[0017] The acquisition unit 111 acquires a physical quantity of the battery 300 from the voltage measurement unit 120 and the current measurement unit 130, or from a configuration not shown. Examples of the physical quantity of the battery 300 include the voltage, the current, and the temperature.

[0018] The detection unit 112 detects a predetermined signal. This predetermined signal refers to a signal that can recognize the establishment of communication between the vehicle and the battery pack, and is typically a signal indicating that communication (CAN, LIN, etc.) has been established between the battery monitoring ECU 100 and a predetermined system related to the operation of the vehicle. An example of the predetermined system related to the operation of the vehicle is the HV-ECU that controls hybrid driving of the vehicle. When the battery monitoring ECU 100 can communicate with the HV-ECU and the state of the HV-ECU has transitioned, it can be determined that the occupant has the intention to start the vehicle, or that the provisional abnormal state of the battery 300 described later is due to a failure of the sensor and not the main body, so this signal is detected.

[0019] The determination unit 114 performs a battery diagnosis to determine the state of the battery 300. More specifically, the determination unit 114 performs a battery diagnosis to determine whether or not a predetermined abnormality occurs in the battery 300 based on the physical quantities of the battery 300 acquired by the acquisition unit 111. The predetermined abnormality determined by this battery diagnosis includes not only an abnormality in the battery 300 itself, but also an abnormality (such as a malfunction) in various sensors used to acquire the physical quantities of the battery 300 and an abnormality (such as a disconnection) in the connection wiring. The determination unit 114 determines whether or not an abnormality occurs in the battery 300 by determining whether or not the current, voltage, and temperature of the battery 300 are equal to or greater than a predetermined threshold value and for a predetermined time set for each of them.

[0020] The control unit 113 judges whether the external charger 500 is connected to the vehicle. More specifically, the control unit 113 judges whether the external charger 500 is connected to the power supply line between the relay 200 and the devices 410 and 420. Whether the external charger 500 is connected to this power supply line can be judged by the control device 110 detecting a voltage change on the power supply line. The control unit 113 also judges whether the external charger 500 connected to the vehicle can output a value required for a predetermined control related to starting the vehicle. The control unit 113 also switches the connection state of the relay 200 to a conductive state (ON) or a non-conductive state (OFF). The switching of the state of the relay 200 is dynamically controlled based on the physical quantity of the battery 300, the detection result of a predetermined signal by the detection unit 112, the voltage difference before and after the relay 200, the result of the battery diagnosis by the determination unit 114, and the like. This relay control will be described later.

[0021] The voltage measurement unit 120 measures the voltage of the battery 300. A voltage sensor (not shown) or the like is used to measure the voltage. The current measured by the voltage measurement unit 120 is output to the control device 110.

[0022] The current measurement unit 130 measures the current (discharging current and charging current) flowing through the battery 300. To measure the current, a current sensor (not shown) capable of detecting the current flowing through a load R inserted in series with the battery 300 is used. The current measured by the current measurement unit 130 is output to the control device 110.

[0023] The above-mentioned control device 110 can typically be configured as an ECU including a processor, a memory, an input / output interface, etc. The control device 110 of the present embodiment realizes all or part of the functions of the above-mentioned acquisition unit 111, detection unit 112, control unit 113, and determination unit 114 by the processor reading and executing a program stored in the memory.

[0024] [control] The control performed by the control device 110 according to this embodiment will be described with further reference to Fig. 2, Fig. 3A, and Fig. 3B. Fig. 2 is a flowchart showing a process procedure of a first example of relay control executed by each component of the control device 110. Fig. 3A and Fig. 3B are flowcharts showing a process procedure of a second example of relay control executed by each component of the control device 110. The process of Fig. 3A and the process of Fig. 3B are connected by connectors X, Y, and Z, respectively.

[0025] [Example 1] 2 is started when relay 200 is electrically cut off and goes into a non-conductive state (OFF). In this first example, examples of situations in which relay 200 goes into a non-conductive state (OFF) include when the amount of charge stored in battery 300 exceeds a predetermined upper limit (overcharged state), when the amount of charge stored in battery 300 exceeds a predetermined lower limit (overdischarged state), when the temperature of battery 300 exceeds a predetermined upper limit (overheated state), when the vehicle has been parked for a long period of time (left unattended for a long period of time), and the like.

[0026] (Step S201) The control unit 113 determines whether or not the external charger 500 is connected to the vehicle. More specifically, the control unit 113 determines whether or not the external charger 500 is connected to the power supply line between the relay 200 and the devices 410 and 420, as a specific operation required to connect the disconnected relay 200. When the control unit 113 determines that the external charger 500 is connected to the vehicle (Yes in step S201), the process proceeds to step S202.

[0027] (Step S202) The control unit 113 determines whether the external charger 500 connected to the vehicle is outputting a first threshold value. This first threshold value is a predetermined power value required for a predetermined control related to starting the vehicle (e.g., READY-ON). Note that a voltage value or a current value may be used as the first threshold value instead of a power value. If the control unit 113 determines that the external charger 500 is outputting the first threshold value (step S202, YES), the process proceeds to step S203, and if the control unit 113 determines that the external charger 500 is not outputting the first threshold value (step S202, NO), the process proceeds to step S201.

[0028] (Step S203) The detection unit 112 determines whether or not a predetermined signal has been detected. Specifically, it determines whether or not communication has been established between the HV-ECU included in the plurality of devices 410 and 420 and the battery monitoring ECU 100. If the detection unit 112 determines that a predetermined signal has been detected (step S203, Yes), the process proceeds to step S204, and if the detection unit 112 determines that a predetermined signal has not been detected (step S203, No), the process proceeds to step S205.

[0029] (Step S204) Control unit 113 changes the first time determined in the next step S205. Typically, control unit 113 makes a change to shorten the first time (for example, from 4 seconds to 1 second). As one example, this change is made for the purpose of increasing the chances of starting the vehicle by prioritizing the connection of relay 200 over waiting for the output of external charger 500 to stabilize. After control unit 113 changes the first time, the process proceeds to step S205.

[0030] The change in the first time period in step S204 may take into account the results of machine learning. As an example, the number of READY-ON operations by a user or the like is counted, and if the count value is greater than a predetermined value, the first time period is shortened. Alternatively, the capacity (SOC) of the battery 300 at the time the vehicle is started by a user or the like is detected, and if the capacity of the battery 300 is low, the first time period is shortened.

[0031] (Step S205) The control unit 113 judges whether or not a state in which the voltage difference across the relay 200 is less than the second threshold continues for a first time or more. The voltage difference across the relay 200 is a voltage difference (Va-Vb) between a voltage value Va on the terminal side of the relay 200 to which the external charger 500 is connected and a voltage value Vb (physical quantity of the battery 300) on the terminal side of the relay 200 to which the battery 300 is connected. The voltage values ​​Va and Vb are acquired by the acquisition unit 111. The second threshold is a predetermined value that is set to prevent a current that may affect the vehicle from instantly flowing from the external charger 500 to the battery 300 when the relay 200 is connected. The first time is a waiting time for judging whether or not a state in which the voltage difference across the relay 200 is less than the second threshold continues stably. If the control unit 113 determines that the state in which the voltage difference before and after relay 200 is less than the second threshold has continued for more than the first hour (step S205, Yes), the process proceeds to step S206, and if the control unit 113 determines that the state in which the voltage difference before and after relay 200 is less than the second threshold has not continued for more than the first hour (step S205, No), the process proceeds to step S202.

[0032] (Step S206) The control unit 113 switches the relay 200 to an electrically connected conductive state (ON). When the control unit 113 switches the relay 200 to a conductive state, this relay control ends. After that, the vehicle transitions to a startable state such as a READY-ON state.

[0033] In this way, in the first example of relay control, if it is possible to recognize that communication has been established between the vehicle and the battery pack, priority is given to connecting the relay 200 rather than determining that the voltage difference across the relay 200 is in a continuous stable state. This allows the vehicle to start even if an external charger 500 with a weak output is connected to the vehicle, thereby increasing the chances of starting the vehicle.

[0034] [Second Example] 3A and 3B is started when relay 200 is electrically cut off and goes into a non-conductive state (OFF). In this second example, relay 200 goes into a non-conductive (OFF) cut-off state when a predetermined abnormality (described later) occurs in battery 300.

[0035] (Step S301) The control unit 113 determines whether or not the external charger 500 is connected to the vehicle. This process is similar to step S201 in the above-described first example. If the control unit 113 determines that the external charger 500 is connected to the vehicle (step S301, Yes), the process proceeds to step S302.

[0036] (Step S302) The control unit 113 determines whether the external charger 500 connected to the vehicle is outputting the first threshold value. This process is similar to step S202 in the above first example. If the control unit 113 determines that the external charger 500 is outputting the first threshold value (step S302, Yes), the process proceeds to step S303, and if the control unit 113 determines that the external charger 500 is not outputting the first threshold value (step S302, No), the process proceeds to step S301.

[0037] (Step S303) The determination unit 114 performs a battery diagnosis to determine whether or not a predetermined abnormality exists in the battery 300, based on the physical quantity of the battery 300 acquired by the acquisition unit 111. After the determination unit 114 performs the battery diagnosis, the process proceeds to step S304.

[0038] (Step S304) Judgment unit 114 judges whether or not there is a predetermined abnormality in battery 300 as a result of the battery diagnosis. If there is an abnormality in battery 300 at this point, judgment unit 114 judges it as a temporary abnormality. If judgment unit 114 judges that there is a predetermined abnormality in battery 300 (step S304, Yes), the process proceeds to step S305, and if it judges that there is no predetermined abnormality in battery 300 (step S304, No), the process proceeds to step S309.

[0039] (Step S305) The detection unit 112 judges whether or not a predetermined signal has been detected. This process is the same as step S203 in the above-mentioned first example. If the detection unit 112 judges that a predetermined signal has been detected (step S305, Yes), the process proceeds to step S306, and if the detection unit 112 judges that a predetermined signal has not been detected (step S305, No), the process proceeds to step S307.

[0040] (Step S306) The control unit 113 changes the first time determined in a later step S309. Typically, the control unit 113 changes the first time to be longer (for example, from 4 seconds to 7 seconds). As an example, this change is made for the purpose of delaying the time to determine an abnormality related to the battery 300 in a later step S307, so as to reliably detect the abnormality at the stage of a provisional abnormality. In addition, the battery diagnosis is periodically performed even after the battery 300 is connected by this relay control. For this reason, it is effective to lengthen the first time in terms of suppressing a decrease in diagnostic accuracy due to disturbance noise being added to the battery diagnosis caused by hastily connecting the battery 300, or suppressing an increase in power consumption of the battery 300 more than necessary. When the control unit 113 changes the first time, the process proceeds to step S309.

[0041] The change in the first time in step S306 may take into account the results of machine learning. As an example, the charging tendency of the user or the like is recorded, and the first time is made longer if there are many jump starts using an external battery rather than the external charger 500. Also, the destination of the vehicle is recorded, and the first time is made longer if the destination is one where a charger with a high output is likely to be connected.

[0042] (Step S307) The determination unit 114 determines whether a second time has elapsed since the determination of a temporary abnormality of the battery 300. This second time is a predetermined waiting time for determining a temporary abnormality as a real abnormality, and is set arbitrarily according to the content of the battery diagnosis, etc. The second time may be the same as or different from the above-mentioned first time. Furthermore, the second time may be changed together with the first time in the above-mentioned step S306. If the determination unit 114 determines that the second time has elapsed (step S307, Yes), the process proceeds to step S308, and if the determination unit 114 determines that the second time has not elapsed (step S307, No), the process proceeds to step S303.

[0043] (Step S308) The determination unit 114 determines that a predetermined abnormality exists in the battery 300 (main abnormality). When the determination unit 114 determines that an abnormality exists in the battery, the main relay control ends without connecting the relay 200.

[0044] (Step S309) The control unit 113 determines whether the state in which the voltage difference across the relay 200 is less than the second threshold has continued for the first hour or more. This process is similar to step S205 in the first example. If the control unit 113 determines that the state in which the voltage difference across the relay 200 is less than the second threshold has continued for the first hour or more (step S309, Yes), the process proceeds to step S310, and if the control unit 113 determines that the state in which the voltage difference across the relay 200 is less than the second threshold has not continued for the first hour or more (step S309, No), the process proceeds to step S302.

[0045] (Step S310) The control unit 113 switches the relay 200 to an electrically connected conductive state (ON). When the control unit 113 switches the relay 200 to a conductive state, this relay control ends. After that, the vehicle transitions to a startable state such as a READY-ON state.

[0046] In this way, in the relay control of the second example, when the presence of an abnormality in the battery 300 is suspected, if the establishment of communication between the vehicle and the battery pack is confirmed, the determination of an abnormality in the battery 300 is prioritized over the connection of the relay 200. This is expected to improve the accuracy of diagnosis of the battery 300.

[0047] <Actions and Effects> As described above, the control device according to an embodiment of the present disclosure dynamically controls the timing of switching the relay provided between the battery and the multiple devices from a non-conductive state (OFF) to a conductive state (ON) based on the physical quantity of the battery and whether or not communication is established between the vehicle and the battery pack. Also, the control device according to an embodiment of the present disclosure dynamically controls the timing of switching the relay provided between the battery and the multiple devices from a non-conductive state (OFF) to a conductive state (ON) based on the presence or absence of an abnormality related to the battery.

[0048] By these controls, the switching of the relay from the disconnected state to the connected state can be appropriately controlled according to the situation of the vehicle.

[0049] The above describes one embodiment of the disclosed technology. However, the present disclosure can be understood not only as a control device, but also as a control method executed by a control device having a processor and a memory, a control program for the control method, a computer-readable non-transitory recording medium storing the control program, or a vehicle equipped with a control device. [Industrial Applicability]

[0050] The control device and the like of the present disclosure can be used to control a battery mounted on a vehicle. [Explanation of symbols]

[0051] 100 Battery monitoring ECU 110 Control device 111 Acquisition Department 112 Detection unit 113 Control Unit 114 Judgment section 120 Voltage measurement section 130 Current measurement section 200 Relay 300 Battery 410, 420 equipment 500 external charger

Claims

1. A control device for controlling a battery, An acquisition unit that acquires a physical quantity of the battery; A detection unit that detects a predetermined signal; a control unit that controls a relay provided between the battery and a predetermined device to which power is supplied from the battery based on the physical quantity of the battery, The control unit is When the relay is cut off, if a state in which a voltage difference across the relay is less than a predetermined voltage value continues for a first period of time, the relay is connected; The control device varies the first time period depending on whether or not the predetermined signal is detected by the detection unit.

2. A determination unit for determining a state of the battery is further provided, The control device according to claim 1 , wherein the control unit maintains the relay in an interrupted state if the determination unit determines that there is an abnormality in the battery while the relay is interrupted.

3. 3. The control device according to claim 2, wherein the determination unit determines that the battery is temporarily abnormal by detecting a predetermined state, and confirms the abnormality of the battery when the temporarily abnormal state continues for a second time period.

4. 4. The control device according to claim 3, wherein when the determination unit determines that the battery is provisionally abnormal and the detection unit detects the specified signal, the control unit changes the first time from when the specified signal is not detected.

5. The control device according to claim 1 , wherein the control unit is configured to shorten the first time period when the predetermined signal is detected by the detection unit, compared to when the predetermined signal is not detected.

6. 6. The control device according to claim 1, wherein the control unit maintains the relay in an OFF state if an output of an external charger connected to the battery via the relay is equal to or lower than a predetermined value while the relay is OFF.

7. The control device is mounted on a vehicle, The control device according to claim 1 , wherein the predetermined signal is a signal indicating that communication has been established between the control device and a system related to the operation of the vehicle.

8. A control method executed by a computer of a control device that controls a battery, comprising: acquiring a physical quantity of the battery; detecting a predetermined signal; a step of connecting a relay provided between the battery and a predetermined device to which power is supplied from the battery when a state in which a voltage difference across the relay is less than a predetermined voltage value continues for a first period of time while the relay is disconnected; and varying the first time period depending on whether or not the predetermined signal is detected.

9. A control program to be executed by a computer of a control device that controls a battery, acquiring a physical quantity of the battery; detecting a predetermined signal; a step of connecting a relay provided between the battery and a predetermined device to which power is supplied from the battery when a state in which a voltage difference across the relay is less than a predetermined voltage value continues for a first period of time while the relay is disconnected; and varying the first time period depending on whether or not the predetermined signal is detected.

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