In-vehicle control device

Abstract

An in-vehicle control device (30) is included in an in-vehicle system (1). The in-vehicle system (1) comprises: a power passage (12) through which power is supplied from a battery (10) to a load (11); and an interruption unit (16) that is switched to an interrupting state in which a current flowing through the power passage (12) is interrupted. The in-vehicle control device (30) comprises a control unit (40). The control unit (40) switches the interruption unit (16) to the interrupting state when the current flowing through the power passage (12) has surpassed a threshold current for a period of time longer than a determination time. The control unit (40) sets the determination time on the basis of the state of the vehicle.

Description

In-vehicle control device

[0001] The present disclosure relates to an in-vehicle control device.

[0002] Patent Document 1 discloses a vehicle power cutoff system. This vehicle power cutoff system includes a cutoff control unit and a pyrotechnic cutoff unit. For example, when the cutoff control unit detects that a current flowing through a conductor of the pyrotechnic cutoff unit exceeds an overcurrent threshold, the cutoff control unit causes the pyrotechnic cutoff unit to perform a cutoff operation.

[0003] Japanese Patent Application Laid-Open No. 2022-13791

[0004] In the above configuration, if the power supply is immediately cut off when the current exceeds the overcurrent threshold, there is a risk that the power supply will be erroneously cut off when noise occurs.

[0005] The present disclosure aims to provide a technique capable of suppressing false blocking caused by noise.

[0006] The vehicle control device disclosed herein is an vehicle control device included in an vehicle system having a power path that supplies power from a battery to a load and a cut-off unit that switches to a cut-off state to cut off the current flowing through the power path, and has a control unit that switches the cut-off unit to the cut-off state when the state in which the current flowing through the power path exceeds a threshold current exceeds a judgment time, and the control unit sets the judgment time based on the state of the vehicle.

[0007] The technology according to the present disclosure can suppress false interruptions caused by noise.

[0008] FIG. 1 is a configuration diagram of an in-vehicle system including an in-vehicle control device of a first embodiment. FIG. 2 is a configuration diagram showing a state when a first battery and a second battery are connected in series in the first embodiment. FIG. 3 is a configuration diagram showing a state when a first battery and a second battery are connected in parallel in the first embodiment. FIG. 4 is a configuration diagram of an in-vehicle system including an in-vehicle control device of a second embodiment. FIG. 5 is a configuration diagram of an in-vehicle system including an in-vehicle control device of a third embodiment. FIG. 6 is a configuration diagram of an in-vehicle system including an in-vehicle control device of a fourth embodiment. FIG. 7 is a configuration diagram of an in-vehicle system including an in-vehicle control device of a fifth embodiment.

[0009] [Description of Embodiments of the Present Disclosure] In the following, embodiments according to the present disclosure are listed and exemplified.

[0010] [1] An in-vehicle control device included in an in-vehicle system having a power path that supplies power from a battery to a load and a cut-off unit that switches to a cut-off state to cut off the current flowing through the power path, the in-vehicle control device having a control unit that switches the cut-off unit to the cut-off state when the state in which the current flowing through the power path exceeds a threshold current exceeds a judgment time, and the control unit sets the judgment time based on the state of the vehicle.

[0011] When the current flowing through the power line exceeds the threshold current, the control unit does not immediately switch the interrupter to the interrupt state, but waits until a determination time has elapsed before switching the interrupter to the interrupt state. This allows the on-board control device to suppress erroneous interruptions caused by noise. Furthermore, the on-board control device can set the determination time taking into account the state of the vehicle.

[0012] [2] The vehicle control device described in [1], wherein the battery includes a first battery and a second battery, the vehicle system is a system in which the first battery and the second battery are switched between a series connection and a parallel connection, and the control unit sets the determination time based on whether the battery is connected in series or in parallel.

[0013] In the case of a series connection, the internal resistance of the battery is high, so components are less likely to heat up even when the current flowing through the power path exceeds the threshold current. In contrast, in the case of a parallel connection, the internal resistance of the battery is low, so components are more likely to heat up when the current flowing through the power path exceeds the threshold current. The above-mentioned on-board control device can suppress false trips caused by noise while suppressing component heat generation by setting the judgment time based on the above-mentioned states in which the components are more likely to heat up.

[0014] [3] The in-vehicle control device according to [2], wherein the control unit determines whether the connection is in series or parallel based on the voltage of the battery.

[0015] According to this configuration, the vehicle control device can determine by itself whether the connection is series or parallel.

[0016] [4] The vehicle control device described in [2], wherein the control unit determines whether the connection is series or parallel based on the current in the conduction path that switches between a state in which current flows and a state in which current does not flow between the series connection and the parallel connection.

[0017] According to this configuration, the vehicle control device can determine by itself whether the connection is series or parallel.

[0018] [5] The in-vehicle control device described in any one of [2] to [4], wherein the in-vehicle system is configured to be able to charge the battery using an external charger, and the control unit sets the determination time based on whether the connection is in series or parallel, and whether the battery is being charged by the external charger or is being discharged.

[0019] The above-described on-board control device can set the determination time based on both whether the connection is series or parallel and whether the external charger is charging or discharging the battery.

[0020] [6] The in-vehicle control device according to [1], wherein the in-vehicle system is configured to be able to charge the battery using an external charger, and the control unit sets the determination time based on whether the battery is being charged by the external charger or is being discharged from the battery.

[0021] The on-board control device can set the determination time based on whether the battery is being charged by an external charger or is being discharged from the battery.

[0022] [7] The in-vehicle control device according to [6], wherein the control unit determines whether the battery is being charged by the external charger or is being discharged based on the direction of current flowing through the power path.

[0023] According to this configuration, the on-board control device can determine by itself whether it is in a charging state or a discharging state.

[0024] [Details of the embodiment of the present disclosure] 1. First embodiment 1-1. Configuration of in-vehicle system 1 The in-vehicle system 1 of the first embodiment shown in Fig. 1 is a system mounted on a vehicle. The in-vehicle system 1 includes a battery 10, a load 11, and a power path 12 that supplies power from the battery 10 to the load 11.

[0025] The battery 10 includes a first battery 10 A and a second battery 10 B. The fully charged voltage of the first battery 10 A and the second battery 10 B is 400 V in this embodiment.

[0026] The in-vehicle system 1 is a system in which a first battery 10A and a second battery 10B are switched between a series connection and a parallel connection. The in-vehicle system 1 includes a switching device 13. The switching device 13 switches between a series connection state in which the first battery 10A and the second battery 10B are connected in series and a parallel connection state in which they are connected in parallel. The switching device 13 includes a first switch unit 13A, a second switch unit 13B, and a third switch unit 13C.

[0027] The power path 12 has a positive power line 12A and a negative power line 12B. The positive terminal of the first battery 10A is electrically connected to the positive power line 12A. A first switch unit 13A is provided between the negative terminal of the first battery 10A and the positive terminal of the second battery 10B. The negative terminal of the second battery 10B is electrically connected to the negative power line 12B. One end of the second switch unit 13B is electrically connected to the positive terminal of the first battery 10A. The other end of the second switch unit 13B is electrically connected to the positive terminal of the second battery 10B and one end of the first switch unit 13A. One end of the third switch unit 13C is electrically connected to the negative terminal of the first battery 10A and the other end of the first switch unit 13A. The other end of the third switch unit 13C is electrically connected to the negative terminal of the second battery 10B.

[0028] As shown in Fig. 2, the switching device 13 is in a series connection state when the first switch unit 13A is in an ON state and the second switch unit 13B and the third switch unit 13C are in an OFF state. As shown in Fig. 3, the switching device 13 is in a parallel connection state when the first switch unit 13A is in an OFF state and the second switch unit 13B and the third switch unit 13C are in an ON state.

[0029] The in-vehicle system 1 includes main relays 14 and 15 provided on the power line 12. The main relay 14 is provided on the positive power line 12A. The main relay 15 is provided on the negative power line 12B.

[0030] The in-vehicle system 1 includes a circuit breaker 16. The circuit breaker 16 is provided in the power path 12. The circuit breaker 16 is provided closer to the battery 10 than the main relay 15. The circuit breaker 16 switches from a permissive state to a cut-off state. The permissive state is a state in which current is allowed to flow through the power path 12. The cut-off state is a state in which current flowing through the power path 12 is cut off. The circuit breaker 16 may be configured by a mechanical switch, a semiconductor switching element, or a pyrotechnic circuit breaker such as a pyro-fuse.

[0031] The in-vehicle system 1 includes a branch path 20, a charging inlet 21, and main relays 22 and 23.

[0032] The branch path 20 branches off from the power path 12 on the side opposite the battery 10 side with respect to the circuit breaker 16. The branch path 20 branches off from the power path 12 on the side opposite the load 11 side with respect to the main relays 14, 15. The branch path 20 has a positive branch line 20A branching off from the positive power line 12A and a negative branch line 20B branching off from the negative power line 12B. The branch path 20 is connected to a charging inlet 21.

[0033] An external charger 90 is connected to charging inlet 21. When external charger 90 connected to charging inlet 21 is a charger capable of charging at 400 V, switching device 13 switches to a parallel connection state based on a signal output from charging inlet 21. When external charger 90 connected to charging inlet 21 is a charger capable of charging at 800 V, switching device 13 switches to a series connection state based on a signal output from charging inlet 21.

[0034] The main relays 22 and 23 are provided in the branch line 20. The main relay 22 is provided in the positive branch line 20A. The main relay 23 is provided in the negative branch line 20B.

[0035] When the main relays 14 and 15 are in the ON state and the main relays 22 and 23 are in the OFF state, the in-vehicle system 1 is in a discharging state in which the battery 10 is discharged to the load 11. When the main relays 14 and 15 are in the OFF state and the main relays 22 and 23 are in the ON state, the in-vehicle system 1 is in a charging state in which power is supplied from the external charger 90 to the battery 10.

[0036] 1-2. Configuration of the Vehicle Control Device 30 The vehicle system 1 includes the vehicle control device 30. The vehicle control device 30 includes the above-described circuit breaker 16, a current detector 31, a voltage detector 32, and a controller 40.

[0037] The current detection unit 31 detects the current flowing through the power path 12. The current detection unit 31 also detects the current flowing from the charging inlet 21 to the battery 10 via the branch path 20 and the power path 12. The current detection unit 31 is configured by, for example, a known current sensor.

[0038] The voltage detection unit 32 detects the voltage of the battery 10. The voltage detection unit 32 is configured by, for example, a known voltage detection circuit.

[0039] The control unit 40 switches the cutoff unit 16 to the cutoff state when the state in which the current flowing through the power path 12 exceeds the threshold current exceeds the determination time. The control unit 40 sets the determination time based on the state of the vehicle. Specifically, the control unit 40 sets the determination time based on whether the connection is series or parallel.

[0040] The control unit 40 may be configured by a microcomputer, a hardware circuit, or a combination of these. The control unit 40 has a state determination unit 41, a determination time setting unit 42, and a cutoff control unit 43.

[0041] A signal indicating the value detected by the voltage detection unit 32 is input to the state determination unit 41. The state determination unit 41 determines whether the battery 10 is connected in series or in parallel based on the voltage of the battery 10. For example, the state determination unit 41 determines that the battery 10 is connected in series when the voltage of the battery 10 is equal to or higher than a determination value (e.g., 600 V), and determines that the battery 10 is connected in parallel when the voltage of the battery 10 is less than the determination value.

[0042] The judgment time setting unit 42 sets the judgment time based on the result of the judgment by the state judgment unit 41. The judgment time setting unit 42 sets a first judgment time when it is judged that the connection is parallel, and sets a second judgment time that is longer than the first judgment time when it is judged that the connection is series.

[0043] A signal indicating the detection value by the current detection unit 31 is input to the cutoff control unit 43. The cutoff control unit 43 repeatedly determines whether the current flowing through the power path 12 has exceeded the threshold current. When the cutoff control unit 43 determines that the current flowing through the power path 12 has exceeded the threshold current, it measures the elapsed time since the current flowing through the power path 12 exceeded the threshold current. When the cutoff control unit 43 determines that the state in which the current flowing through the power path 12 has exceeded the threshold current has exceeded the determination time set by the determination time setting unit 42, the cutoff control unit 43 switches the cutoff unit 16 from the allowable state to the cutoff state.

[0044] 1-3. Effects As described above, the control unit 40 switches the cutoff unit 16 to the cutoff state when the state in which the current flowing through the power path 12 exceeds the threshold current exceeds the determination time. When the current flowing through the power path 12 exceeds the threshold current, the likelihood of components generating heat differs depending on whether the battery 10 is connected in series or in parallel. Specifically, when the battery 10 is connected in series, the internal resistance of the battery 10 is high, making it difficult for components to generate heat even when the current flowing through the power path 12 exceeds the threshold current. In contrast, when the battery 10 is connected in parallel, the internal resistance of the battery 10 is low, making it easy for components to generate heat when the current flowing through the power path 12 exceeds the threshold current. By setting the determination time based on the above-described states in which the likelihood of components generating heat differs, the onboard control device 30 can suppress noise-induced erroneous cutoff while suppressing component heat generation.

[0045] Furthermore, the vehicle control device 30 can determine by itself whether the connection is series or parallel.

[0046] 2. Second Embodiment In the second embodiment, a configuration will be described in which a different method is used to determine whether the connection is series or parallel. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0047] 4 includes an in-vehicle control device 230 instead of the in-vehicle control device 30 described in the first embodiment. The in-vehicle system 201 is common to the in-vehicle system 1 of the first embodiment in other respects.

[0048] The vehicle control device 230 includes a breaker 16 , a current detector 31 , a second current detector 232 , and a controller 240 .

[0049] The second current detection unit 232 detects the current in the conductive path 233, which switches between a state in which a current flows and a state in which a current does not flow depending on whether the conductive path 233 is connected in series or in parallel. The second current detection unit 232 is configured by, for example, a known current sensor.

[0050] The control unit 240 has a state determination unit 241, a determination time setting unit 42, and a cutoff control unit 43. A signal indicating a detection value by the second current detection unit 232 is input to the state determination unit 241. The state determination unit 241 determines whether the connection is series or parallel based on the current in the conductive path 233, which switches between a state in which a current flows and a state in which no current flows depending on whether the connection is series or parallel. In the case of a series connection, no current flows in the conductive path 233, and in the case of a parallel connection, current flows in the conductive path 233. Therefore, the state determination unit 241 determines that the connection is parallel when a current flows in the conductive path 233, and determines that the connection is series when no current flows in the conductive path 233.

[0051] As described above, the on-board control device 230 can determine by itself whether the connection is series or parallel using a method different from that in the first embodiment.

[0052] In the third embodiment, a configuration is described in which it is determined whether the connection is series or parallel based on a signal input from an external ECU. In the third embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

[0053] 5, an in-vehicle system 301 of the third embodiment further includes an external ECU 80 in addition to the components of the in-vehicle system 1 described in the first embodiment. The in-vehicle system 301 also includes an in-vehicle control device 330 instead of the in-vehicle control device 30 described in the first embodiment. The in-vehicle system 301 is otherwise common to the in-vehicle system 1 of the first embodiment.

[0054] The in-vehicle control device 330 includes the cutoff unit 16, a current detection unit 31, and a control unit 340. The control unit 340 includes a state determination unit 341, a determination time setting unit 42, and a cutoff control unit 43.

[0055] A signal indicating whether the connection is in series or parallel is input to the state determination unit 341 from the external ECU 80. The external ECU 80 is a device that switches the switching device 13 between the parallel connection state and the series connection state in response to a signal output from, for example, the external charger 90. The state determination unit 341 determines whether the connection is in series or parallel based on the signal input from the external ECU 80.

[0056] As described above, the in-vehicle control device 330 can determine whether the connection is series or parallel based on the signal input from the external ECU 80 .

[0057] 4. Fourth Embodiment In the fourth embodiment, a configuration will be described in which the determination time is set based on whether the connection is series or parallel, and whether the battery is being charged by an external charger or is being discharged from the battery. In the fourth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0058] 6 includes an in-vehicle control device 430 instead of the in-vehicle control device 30 described in the first embodiment. The in-vehicle system 401 is common to the in-vehicle system 1 of the first embodiment in other respects.

[0059] The in-vehicle control device 430 includes the cutoff unit 16, a current detection unit 31, a voltage detection unit 32, and a control unit 440. The control unit 440 includes a state determination unit 441, a determination time setting unit 442, and a cutoff control unit 43.

[0060] A signal indicating the value detected by the voltage detection unit 32 is input to the state determination unit 441. The state determination unit 441 determines whether the battery 10 is connected in series or in parallel based on the voltage of the battery 10. For example, the state determination unit 441 determines that the battery 10 is connected in series when the voltage of the battery 10 is equal to or higher than a determination value (e.g., 600 V), and determines that the battery 10 is connected in parallel when the voltage of the battery 10 is less than the determination value.

[0061] A signal indicating the value detected by the current detection unit 31 is input to the state determination unit 441. The state determination unit 441 determines whether the battery is being charged by the external charger 90 or is being discharged from the battery 10 based on the direction of the current flowing through the power path 12. Specifically, because the current detection unit 31 detects the current flowing through the negative power line 12B, the state determination unit 441 determines that the battery is being discharged when the current flows toward the battery 10, and determines that the battery is being charged when the current flows from the battery 10.

[0062] The in-vehicle system 401 switches between a first state in which the battery 10 is in a charging state and is connected in parallel, a second state in which the battery 10 is in a charging state and is connected in series, and a third state in which the battery 10 is in a discharging state and is connected in series. The in-vehicle system 401 is in the first state when charging is performed by the external charger 90 at 400 V. The in-vehicle system 401 is in the second state when charging is performed by the external charger 90 at 800 V. The in-vehicle system 401 is in the third state when discharging is performed from the battery 10 to the load 11.

[0063] The state determination unit 441 determines whether the current state is the first state, the second state, or the third state.

[0064] The judgment time setting unit 442 sets the judgment time based on the result of the judgment by the state judgment unit 441. In the first state, the internal resistance of the battery 10 is low, so it is preferable that the judgment time be short. In the second and third states, the internal resistance of the battery 10 is high, so it is preferable that the judgment time be long. In particular, the third state includes the vehicle's running state, so it is more important not to erroneously shut off the cutoff unit 16. For this reason, the judgment time setting unit 442 sets a first judgment time when it is determined that the state is the first state, sets a second judgment time longer than the first judgment time when it is determined that the state is the second state, and sets a third judgment time longer than the second judgment time when it is determined that the state is the third state.

[0065] As described above, the in-vehicle control device 430 can set the judgment time based on both whether the connection is series or parallel, and whether the external charger 90 is charging or the battery 10 is discharging.

[0066] 5. Fifth Embodiment In the fifth embodiment, a configuration will be described in which a determination time is set based on whether the battery is in a charging state or a discharging state. In the fifth embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0067] 7 includes an in-vehicle control device 530 instead of the in-vehicle control device 30 described in the first embodiment. The in-vehicle system 501 is common to the in-vehicle system 1 of the first embodiment in other respects.

[0068] The vehicle control device 530 includes the cutoff unit 16, a current detection unit 31, and a control unit 540. The control unit 540 includes a state determination unit 541, a determination time setting unit 542, and a cutoff control unit 43.

[0069] A signal indicating the value detected by the current detection unit 31 is input to the state determination unit 541. The state determination unit 541 determines whether the battery 10 is being charged by the external charger 90 or is being discharged based on the direction of the current flowing through the power path 12.

[0070] The judgment time setting unit 542 sets the judgment time based on the result of the judgment by the state judgment unit 541. The judgment time setting unit 542 sets a first judgment time when it is judged that the battery is in the charging state, and sets a second judgment time that is longer than the first judgment time when it is judged that the battery is in the discharging state.

[0071] As described above, the on-board control device 530 can set the determination time based on whether the battery is being charged by the external charger 90 or is being discharged from the battery 10. The on-board control device 530 can also determine by itself whether the battery is being charged or discharged.

[0072] <Other Embodiments> The present disclosure is not limited to the embodiments described above and in the drawings. For example, any combination of features of the above-described or below-described embodiments is possible within a range that does not contradict. Furthermore, any feature of the above-described or below-described embodiments may be omitted unless explicitly stated as essential. Furthermore, the above-described embodiments may be modified as follows.

[0073] In the second embodiment, the conductive path that switches between a state in which a current flows and a state in which a current does not flow depending on whether the connection is in series or parallel is the conductive path through which a current flows in the parallel connection. However, the conductive path that switches between a state in which a current flows and a state in which a current does not flow depending on whether the connection is in series or parallel may be the conductive path through which a current flows in the series connection.

[0074] It should be noted that the embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments disclosed herein, and is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims.

[0075] REFERENCE SIGNS LIST 1...In-vehicle system 10...Battery 10A...First battery 10B...Second battery 11...Load 12...Power path 12A...Positive side power line 12B...Negative side power line 13...Switching device 13A...First switch unit 13B...Second switch unit 13C...Third switch unit 14...Main relay 15...Main relay 16...Breakdown unit 20...Branch path 20A...Positive side branch line 20B...Negative side branch line 21...Charging inlet 22...Main relay 23...Main relay 30...In-vehicle control device 31...Current detection unit 32...Voltage detection unit 40...Control unit 41...State determination unit 42...Determination time setting unit 43...Breakdown control unit 80...External ECU 90...External charger 201...In-vehicle system 230...In-vehicle control device 232...Second current detection unit 233... Conduction path 240... Control unit 241... State determination unit 301... In-vehicle system 330... In-vehicle control device 340... Control unit 341... State determination unit 401... In-vehicle system 430... In-vehicle control device 440... Control unit 441... State determination unit 442... Determination time setting unit 501... In-vehicle system 530... In-vehicle control device 540... Control unit 541... State determination unit 542... Determination time setting unit

Claims

1. An in-vehicle control device included in an in-vehicle system having a power path that supplies power from a battery to a load and a cutoff unit that switches to a cutoff state to cut off the current flowing through the power path, the in-vehicle control device having a control unit that switches the cutoff unit to the cutoff state when the state in which the current flowing through the power path exceeds a threshold current exceeds a judgment time, and the control unit sets the judgment time based on the state of the vehicle.

2. The vehicle control device according to claim 1, wherein the battery includes a first battery and a second battery, the vehicle system is a system in which the first battery and the second battery are switched between a series connection and a parallel connection, and the control unit sets the determination time based on whether the battery is connected in series or in parallel.

3. The vehicle control device according to claim 2, wherein the control unit determines whether the connection is in series or parallel based on the voltage of the battery.

4. The vehicle control device according to claim 2, wherein the control unit determines whether the connection is in series or parallel based on the current in the conduction path that switches between a state in which current flows and a state in which current does not flow between the series connection and the parallel connection.

5. The in-vehicle control device according to any one of claims 2 to 4, wherein the in-vehicle system is configured to be able to charge the battery using an external charger, and the control unit sets the determination time based on whether the connection is in series or parallel, and whether the battery is being charged by the external charger or is being discharged.

6. The in-vehicle control device according to claim 1, wherein the in-vehicle system is configured to be able to charge the battery using an external charger, and the control unit sets the determination time based on whether the battery is being charged by the external charger or is being discharged from the battery.

7. The in-vehicle control device according to claim 6, wherein the control unit determines whether the external charger is charging the battery or the battery is discharging the battery, based on the direction of the current flowing through the power path.

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