Abnormality determination device

Abstract

An abnormality determination device (1) is for a vehicle (100) comprising: a battery (10) that supplies power to a load (11); a relay (12) provided between the battery (10) and the load (11); a battery case (13) that accommodates the battery (10) and the relay (12); and a power supply unit (14) provided outside the battery case (13). The abnormality determination device (1) is provided with control units (a first control unit (2) and a second control unit (3)) that control the relay (12) to the ON state in a start state and in a parking state of the vehicle (100). In a state in which power is supplied from the power supply unit (14) to the load (11), the control units perform control for switching the relay (12) to the OFF state, and determines whether or not the relay (12) is switched to the OFF state.

Description

Abnormality determination device

[0001] The present disclosure relates to an abnormality determination device.

[0002] In recent years, due to environmental considerations, lithium-ion batteries and the like have been used as an alternative to lead-acid batteries. Lithium-ion batteries differ from lead-acid batteries in that they have a built-in protective relay to prevent smoke and fire. For example, Patent Document 1 discloses a battery pack to be mounted on an automobile. This battery pack includes a battery module and a switch that switches on and off the power supply from the battery module to the outside.

[0003] International Publication No. 2017 / 191679

[0004] To ensure that the battery module always supplies power to the load, regardless of whether the vehicle is started or parked, the switch must be kept on. If the switch is always on, there is a problem that a fault in the switch not turning off cannot be detected. Furthermore, there is a problem that turning the switch off to check whether the switch has turned off interrupts the power supply to the load.

[0005] The present disclosure aims to provide a technique that can check whether a relay is switched to the off state while preventing interruption of power supply to a load.

[0006] The abnormality determination device of the present disclosure is an abnormality determination device included in a vehicle that has a battery that supplies power to a load, a relay provided between the battery and the load, a battery case that houses the battery and the relay, and a power supply unit that is provided outside the battery case, and includes a control unit that controls the relay to be in an on state when the vehicle is in a starting state and a parking state, and the control unit controls the relay to be in an off state when power is being supplied to the load from the power supply unit, and determines whether the relay has been switched to the off state.

[0007] According to the technology of the present disclosure, it is possible to check whether the relay is switched to the off state while preventing interruption of the power supply to the load.

[0008] FIG. 1 is a schematic diagram illustrating a vehicle including an abnormality determination device according to a first embodiment. FIG. 2 is a flowchart illustrating a process flow performed by a second control unit according to the first embodiment. FIG. 3 is a flowchart illustrating a process flow performed by a first control unit according to the first embodiment. FIG. 4 is a flowchart illustrating a first process flow performed by a second control unit according to a second embodiment. FIG. 5 is a flowchart illustrating a second process flow performed by a second control unit according to the second embodiment. FIG. 6 is a flowchart illustrating a process flow performed by a second control unit according to a third embodiment. FIG. 7 is a schematic diagram illustrating a vehicle including an abnormality determination device according to a fourth embodiment. FIG. 8 is a flowchart illustrating a process flow performed by a second control unit according to the fourth embodiment.

[0009] [Description of Embodiments of the Present Disclosure] First, embodiments of the present disclosure will be listed and described.

[0010] [1] An abnormality determination device included in a vehicle that includes: a battery that supplies power to a load; a relay provided between the battery and the load; a battery case that houses the battery and the relay; and a power supply unit that is provided outside the battery case, the abnormality determination device further including a control unit that controls the relay to be in an on state when the vehicle is in a starting state and a parking state, and the control unit controls the relay to be in an off state when power is being supplied from the power supply unit to the load, and determines whether the relay has been switched to the off state.

[0011] The abnormality determination device controls the relay to be in the ON state in the starting state and the parking state, thereby supplying power from the battery to the load in the starting state and the parking state. Furthermore, the abnormality determination device controls the relay to be in the OFF state when power is being supplied to the load from the power supply unit, and determines whether the relay has been switched to the OFF state. In other words, the abnormality determination device can check whether the relay has been switched to the OFF state while preventing the power supply to the load from being interrupted.

[0012] [2] The abnormality determination device described in [1], wherein the control unit controls the relay to be switched to the off state when the vehicle switches to the starting state and power supply from the power supply unit begins, and determines whether the relay has switched to the off state.

[0013] The abnormality determination device can check whether the relay is switched to the OFF state at an early stage after the vehicle is switched to the starting state.

[0014] [3] The abnormality determination device described in [2], wherein the control unit performs control to switch the relay to the off state when the vehicle switches to the starting state, power supply from the power supply unit begins, and the control unit determines that the shift range of the vehicle is the parking range, and determines whether the relay has switched to the off state.

[0015] The abnormality determination device can check whether the relay is switched to the OFF state before the vehicle starts to move.

[0016] [4] The load includes a driving load that is stopped in the parking state, and when the vehicle switches to the parking state, the control unit controls the relay to switch to the off state while maintaining the power supply from the power supply unit, determines whether the relay has switched to the off state, and after making the determination, switches the relay to the on state and then stops the power supply from the power supply unit. An abnormality determination device described in any one of [1] to [3].

[0017] When the vehicle switches to a parked state, the abnormality determination device checks whether the relay switches to the off state before stopping the power supply from the power supply unit. Since the load for driving is stopped in the parked state, the load current is small, and even if the relay is switched to the off state for battery diagnosis, the power supply unit can maintain the power supply to other loads. Therefore, the abnormality determination device can check whether the relay switches to the off state while minimizing an increase in processing while the vehicle is running.

[0018] [5] An abnormality determination device described in any one of [1] to [4], wherein the control unit, when determining that the power supply unit has a predetermined power margin or more, controls the relay to switch to an off state and determines whether the relay has switched to an off state.

[0019] The abnormality determination device checks whether the relay should be switched off when it determines that the power supply unit has a capacity that is equal to or greater than a predetermined capacity, and therefore the abnormality determination device can easily prevent a shortage of power supply to the load due to the relay being switched off.

[0020] [6] When the control unit determines that the power supply unit's remaining capacity is less than a predetermined remaining capacity, the control unit suppresses the power supply from the power supply unit to the load, then controls the relay to switch to an off state, and determines whether the relay has switched to an off state. An abnormality determination device described in any one of [1] to [5].

[0021] When the abnormality determination device determines that the power margin of the power supply unit is less than a predetermined power margin, it suppresses the power supply from the power supply unit to the load and then checks whether the relay is switched off. Therefore, the abnormality determination device can easily prevent a shortage of power supply to the load due to the relay being switched off.

[0022] [7] The control unit starts the supply of power from the power supply unit in the parking state and controls the relay to be switched to the off state, and determines whether the relay has been switched to the off state. An abnormality determination device described in any one of [1] to [6].

[0023] The abnormality determination device can check whether the relay switches to the OFF state while preventing the power supply to the load from being interrupted in the parked state.

[0024] [Details of the embodiments of the present disclosure] <First embodiment> Fig. 1 discloses an abnormality determination device 1 included in a vehicle 100. In this embodiment, the vehicle 100 is an engine-equipped vehicle. The vehicle 100 switches between a start state and a parked state. The start state is when a start switch of the vehicle 100 is in an on state. The parked state is when a start switch of the vehicle 100 is in an off state. In this embodiment, the start switch is an ignition switch.

[0025] The vehicle 100 includes a battery 10 , a load 11 , a relay 12 , a battery case 13 , a power supply unit 14 , current detection units 15 and 16 , a first power path 21 , a second power path 22 , and a branch path 23 .

[0026] The battery 10 is a power supply source that supplies power to the load 11. The battery 10 is, for example, a lithium-ion battery. The battery 10 is, for example, a low-voltage battery. The positive terminal of the battery 10 is electrically connected to a first power path 21. The output voltage of the battery 10 is applied to the first power path 21. The negative terminal of the battery 10 is electrically connected to ground.

[0027] The load 11 includes a driving load that stops when the vehicle 100 is parked, and a specific load that operates by receiving a supply of dark current when the vehicle 100 is parked. The specific load is, for example, a car navigation system, an audio system, a drive recorder, etc.

[0028] The relay 12 is provided between the battery 10 and the load 11. The relay 12 may be a mechanical relay having contacts or a relay configured with a semiconductor switching element. The relay 12 is, for example, a normally-on type. A first power path 21 is provided between the relay 12 and the battery 10. A second power path 22 is provided between the relay 12 and the load 11. When the relay 12 is in an on state, the relay 12 allows a current to flow from the first power path 21 to the second power path 22 and allows a current to flow from the second power path 22 to the first power path 21. When the relay 12 is in an off state, the relay 12 blocks a current from flowing from the first power path 21 to the second power path 22 and blocks a current from flowing from the second power path 22 to the first power path 21.

[0029] The battery case 13 accommodates the battery 10 and the relay 12 .

[0030] The power supply unit 14 is provided outside the battery case 13. The power supply unit 14 is electrically connected to a branch path 23 branching from the second power path 22. The output voltage of the power supply unit 14 is applied to the branch path 23. The power supply unit 14 supplies power to the load 11 via the branch path 23 and the second power path 22. The power supply unit 14 has an engine 31 and an alternator 32. The alternator 32 is driven by the engine 31. The alternator 32 supplies generated power to the branch path 23. The alternator 32 includes a regulator and outputs regulated voltage. The power supply unit 14 starts supplying power when the engine 31 starts.

[0031] The current detection unit 15 detects the current flowing through the relay 12. The current detection unit 15 is, for example, a known current sensor. The current detection unit 15 outputs a signal indicating the detected value.

[0032] The current detection unit 16 detects the output current of the power supply unit 14. The current detection unit 16 is, for example, a known current sensor. The current detection unit 16 outputs a signal indicating the detected value.

[0033] The abnormality determination device 1 is included in the vehicle 100. The abnormality determination device 1 includes a first control unit 2 and a second control unit 3. The first control unit 2 and the second control unit 3 correspond to examples of a control unit. The first control unit 2 and the second control unit 3 are each configured to include a microcomputer. The first control unit 2 is housed in a battery case 13. The second control unit 3 is provided outside the battery case 13. The first control unit 2 and the second control unit 3 are capable of communicating with each other.

[0034] The first control unit 2 controls the relay 12. The first control unit 2 detects the current flowing through the relay 12 based on the signal output from the current detection unit 15. When the first control unit 2 determines that a protection condition is met, it switches the relay 12 to the off state. Examples of the protection condition include the current flowing through the relay 12 exceeding an overcurrent threshold, or the output voltage of the battery 10 falling below a low voltage threshold.

[0035] An on / off signal indicating the on / off state of the start switch is input to the second control unit 3. The second control unit 3 detects the on / off state of the start switch based on the on / off signal.

[0036] The second control unit 3 controls the power supply unit 14 via a power supply control unit 4 provided in the vehicle 100. The second control unit 3 starts the engine 31 when a start condition is met, and stops the engine 31 when a stop condition is met. In other words, the second control unit 3 starts the power supply unit 14 when a start condition is met, and stops the power supply from the power supply unit 14 when a stop condition is met. The start condition may be, for example, that the start switch is switched to the ON state, that the brake pedal is depressed less from the idle stop state, or some other condition. The stop condition may be that the start switch is switched to the OFF state, that the brake pedal is depressed to a certain amount or more and the engine is switched to the idle stop state, or some other condition.

[0037] The second control unit 3 controls the output voltage of the power supply unit 14 (specifically, the alternator 32). The second control unit 3 receives a signal output from the current detection unit 16 via the power supply control unit 4. The second control unit 3 detects the output current of the power supply unit 14 based on the signal output from the current detection unit 16.

[0038] The first control unit 2 controls the relay 12 to be in the ON state when the vehicle 100 is in the starting state or the parking state.

[0039] The second control unit 3 outputs a diagnostic command to the first control unit 2 when power is being supplied from the power supply unit 14 to the load 11. The second control unit 3 determines whether power is being supplied from the power supply unit 14 to the load 11 based on the output current of the power supply unit 14. Specifically, the second control unit 3 determines that power is being supplied from the power supply unit 14 to the load 11 when the output current of the power supply unit 14 is greater than a supply determination value (e.g., 0 A). The second control unit 3 determines that power is not being supplied from the power supply unit 14 to the load 11 when the output current of the power supply unit 14 is equal to or less than the supply determination value (e.g., 0 A). The second control unit 3 outputs a diagnostic command to the first control unit 2 when it determines that power is being supplied from the power supply unit 14 to the load 11.

[0040] The second control unit 3 outputs a diagnostic command when the vehicle 100 switches to the start state and the supply of power from the power supply unit 14 starts. The second control unit 3 determines whether the vehicle 100 has switched to the start state based on the on / off signal. The second control unit 3 determines that the vehicle 100 has switched to the start state when the start switch switches from the off state to the on state. The second control unit 3 determines that the vehicle 100 has switched to the start state and that power is being supplied from the power supply unit 14 to the load 11 when it determines that the vehicle 100 has switched to the start state and that power supply from the power supply unit 14 has started. The second control unit 3 outputs a diagnostic command when it determines that the vehicle 100 has switched to the start state and that power supply from the power supply unit 14 has started.

[0041] When a diagnostic command is input, the first control unit 2 controls the relay 12 to switch to the off state and determines whether the relay 12 has switched to the off state. Specifically, the first control unit 2 outputs an off signal to the relay 12 and detects the current flowing through the relay 12. The first control unit 2 then determines whether the relay 12 has switched to the off state based on the current flowing through the relay 12. The first control unit 2 determines that the relay 12 has switched to the off state when the current flowing through the relay 12 is equal to or less than an off determination value (e.g., 0 A). The first control unit 2 determines that the relay 12 has not switched to the off state when the current flowing through the relay 12 is greater than the off determination value. After determining whether the relay 12 has switched to the off state, the first control unit 2 returns the relay 12 to the on state.

[0042] The following description relates to specific examples of the operations of the first control unit 2 and the second control unit 3. The first control unit 2 maintains the relay 12 in an on state regardless of whether the vehicle 100 is in a starting state or a parking state. The second control unit 3 starts the process shown in FIG. 2 when the vehicle 100 switches to a parking state. In step S11, the second control unit 3 determines whether the vehicle has switched to a starting state. The second control unit 3 repeats the process of step S11 until it determines that the vehicle has switched to a starting state. If the second control unit 3 determines that the vehicle has switched to a starting state, it determines in step S12 whether power supply from the power supply unit 14 has started. The second control unit 3 repeats the process of step S12 until it determines that power supply from the power supply unit 14 has started. If the second control unit 3 determines that power supply from the power supply unit 14 has started, it outputs a diagnostic command to the first control unit 2 in step S13.

[0043] After outputting the diagnostic command, the second control unit 3 determines in step S14 whether or not the diagnostic result has been received from the first control unit 2. The second control unit 3 repeats the process of step S14 until the diagnostic result has been received. If the second control unit 3 determines that the diagnostic result has been received, it determines in step S15 whether or not the relay 12 is normal based on the diagnostic result. If the second control unit 3 determines that the relay 12 is normal, it outputs information indicating that the diagnosis has been completed to an external device in step S16. If the second control unit 3 determines that the relay 12 is not normal, it performs an abnormality response process in step S17. The abnormality response process is, for example, a process of notifying an external device or a driver that an abnormality has occurred. After step S16 or step S17, the second control unit 3 ends the process shown in FIG. 2 .

[0044] The first control unit 2 always performs the process shown in FIG. 3 , for example. That is, the first control unit 2 resumes the process shown in FIG. 3 immediately after completing the process shown in FIG. 3 . The first control unit 2 determines whether a diagnostic command has been received in step S21. The first control unit 2 repeats the process of step S21 until the diagnostic command is received. If the first control unit 2 receives the diagnostic command, the first control unit 2 switches the relay 12 to the OFF state in step S22, and determines whether the relay 12 has been switched to the OFF state in step S23. If the first control unit 2 determines that the relay 12 has been switched to the OFF state, the first control unit 2 controls the relay 12 to be switched to the ON state in step S24, and notifies the second control unit 3 of a diagnostic result indicating a normal state in step S25. If the first control unit 2 determines that the relay 12 has not been switched to the OFF state, the first control unit 2 controls the relay 12 to be switched to the ON state in step S26, and notifies the second control unit 3 of a diagnostic result indicating an abnormality in step S27. After step S25 or step S27, the first control unit 2 ends the process shown in FIG.

[0045] The following description relates to the effects of the abnormality determination device 1 of the first embodiment. The abnormality determination device 1 controls the relay 12 to be in the ON state in the starting state and the parking state, thereby enabling power to be supplied from the battery 10 to the load 11 in the starting state and the parking state. Furthermore, the abnormality determination device 1 controls the relay 12 to be switched to the OFF state while power is being supplied from the power supply unit 14 to the load 11, and determines whether the relay 12 has been switched to the OFF state. In other words, the abnormality determination device 1 can check whether the relay 12 has been switched to the OFF state while preventing the power supply to the load 11 from being interrupted.

[0046] The abnormality determination device 1 can check whether the relay 12 is switched to the OFF state at an early stage after the vehicle 100 is switched to the starting state.

[0047] Second Embodiment In the second embodiment, an example will be described in which it is confirmed whether or not the relay 12 is switched to the OFF state, provided that the shift range is the parking range when the vehicle 100 is switched to the start state. The second embodiment also describes an example in which it is confirmed whether or not the relay 12 is switched to the OFF state when the vehicle 100 is switched to the parking state. Note that the configuration of the second embodiment is the same as the configuration shown in FIG. 1 described in the first embodiment, and therefore will be described with reference to FIG. 1.

[0048] In the second embodiment, the second control unit 3 outputs a diagnostic command when the vehicle 100 switches to a start state, power supply from the power supply unit 14 begins, and the second control unit 3 determines that the shift range of the vehicle 100 is the parking range. A shift signal indicating the selected shift range is input to the second control unit 3. The second control unit 3 determines whether the current shift range is the parking range based on the shift signal. The operation of the first control unit 2 is the same as in the first embodiment.

[0049] When the abnormality determination device 1 is unable to confirm whether or not the relay 12 is switched to the OFF state when the vehicle 100 is switched to the starting state, the abnormality determination device 1 confirms whether or not the relay 12 is switched to the OFF state when the vehicle 100 is switched to the parking state.

[0050] When the start switch is switched to the OFF state, the second control unit 3 stops the engine 31 and stops the power supply from the power supply unit 14. However, when the start switch is switched to the OFF state, the second control unit 3 outputs a diagnostic command and stops the engine 31 after receiving the diagnostic result. Specifically, when the vehicle 100 is switched to the parked state, the second control unit 3 controls the relay 12 to be switched to the OFF state while maintaining the power supply from the power supply unit 14, determines whether the relay 12 has been switched to the OFF state, and after making the determination, switches the relay 12 to the ON state and then stops the power supply from the power supply unit 14. In other words, when the vehicle 100 is switched to the parked state, the abnormality determination device 1 stops the power supply from the power supply unit 14 after confirming whether the relay 12 has been switched to the OFF state. In the parked state, the load for driving included in the load 11 is stopped, so the load current is small. Therefore, even if the relay 12 is switched to the OFF state for diagnosing the battery 10, the power supply unit 14 can maintain the power supply to the other loads 11. Therefore, the abnormality determination device 1 can check whether the relay 12 is switched to the OFF state while suppressing an increase in the amount of processing while the vehicle is running.

[0051] If the second control unit 3 does not output a diagnostic command when switching to the parking state, the second control unit 3 immediately stops the engine 31 after the start switch is switched to the off state.

[0052] The second control unit 3 starts the process shown in FIG. 4 when the vehicle 100 switches to the parking state. In step S31, the second control unit 3 determines whether the vehicle has switched to the starting state. The second control unit 3 repeats the process of step S31 until the vehicle 100 switches to the starting state. When the second control unit 3 determines that the vehicle has switched to the starting state, the second control unit 3 determines whether a diagnosis for the day has been performed in step S32. When the second control unit 3 determines that a diagnosis for the day has been performed, the second control unit 3 ends the process shown in FIG. 4. When the second control unit 3 determines that a diagnosis for the day has not been performed, the second control unit 3 determines whether power supply from the power supply unit 14 has started in step S33. The second control unit 3 repeats the process of step S33 until it determines that power supply from the power supply unit 14 has started. When the second control unit 3 determines that power supply from the power supply unit 14 has started, the second control unit 3 determines whether the current shift range is the parking range in step S34. If the second control unit 3 determines that the current shift range is not the parking range, it outputs information indicating that the diagnosis has not been performed to an external device in step S40. Thereafter, the second control unit 3 ends the process shown in FIG.

[0053] If the second control unit 3 determines that the current shift range is the parking range, it outputs a diagnostic command to the first control unit 2 in step S35. After outputting the diagnostic command, the second control unit 3 determines whether or not it has received a diagnostic result from the first control unit 2 in step S36. The second control unit 3 repeats the process of step S36 until it receives the diagnostic result. If it determines that it has received the diagnostic result, it determines whether or not the relay 12 is normal based on the diagnostic result in step S37. If it determines that the relay 12 is normal, the second control unit 3 outputs information indicating that the diagnosis is complete to an external device in step S38. If it determines that the relay 12 is not normal, the second control unit 3 performs an abnormality response process in step S39. The abnormality response process is, for example, a process of notifying an external device that an abnormality has occurred. After step S38 or step S39, the second control unit 3 ends the process shown in FIG. 4.

[0054] The second control unit 3 performs the process shown in FIG. 5 when the vehicle 100 is in a start-up state. In step S41 of FIG. 5, the second control unit 3 determines whether the vehicle 100 has switched to a parked state. The second control unit 3 repeats the process of step S41 until it determines that the vehicle 100 has switched to a parked state. If the second control unit 3 determines that the vehicle 100 has switched to a parked state, it determines in step S42 whether a diagnosis for the day has been performed. If the second control unit 3 determines that a diagnosis for the day has been performed, it stops the power supply from the power supply unit 14 in step S43 without outputting a diagnosis command. If the second control unit 3 determines that a diagnosis for the day has not been performed, it maintains the power supply from the power supply unit 14 in step S44 and outputs a diagnosis command in step S45.

[0055] After outputting the diagnostic command, the second control unit 3 determines in step S46 whether or not the diagnostic result has been received from the first control unit 2. The second control unit 3 repeats the process of step S46 until the diagnostic result has been received. If the second control unit 3 determines that the diagnostic result has been received, the second control unit 3 stops the power supply from the power supply unit 14 in step S47, and determines whether or not the relay 12 is normal based on the diagnostic result in step S48. If the second control unit 3 determines that the relay 12 is normal, the second control unit 3 outputs information indicating that the diagnosis has been completed to an external device in step S49. If the second control unit 3 determines that the relay 12 is not normal, the second control unit 3 performs an abnormality response process in step S50. The abnormality response process is, for example, a process of notifying an external device that an abnormality has occurred. After step S49 or step S50, the second control unit 3 ends the process shown in FIG. 5.

[0056] As described above, when the vehicle 100 is switched to the start state, the power supply from the power supply unit 14 is started, and the abnormality determination device 1 of the second embodiment determines whether the relay 12 has been switched to the off state, and determines whether the relay 12 has been switched to the off state. With this configuration, the abnormality determination device 1 can check whether the relay 12 has been switched to the off state before the vehicle 100 starts traveling.

[0057] Furthermore, the abnormality determination device 1 checks whether the relay 12 is switched to the OFF state when the vehicle 100 switches to the parking state. Specifically, when the vehicle 100 switches to the parking state, the second control unit 3 controls the relay 12 to switch to the OFF state while maintaining the power supply from the power supply unit 14. The abnormality determination device 1 determines whether the relay 12 has switched to the OFF state, and after making the determination, switches the relay 12 to the ON state and then stops the power supply from the power supply unit 14. In other words, when the vehicle 100 switches to the parking state, the abnormality determination device 1 checks whether the relay 12 is switched to the OFF state and then stops the power supply from the power supply unit 14. In the parking state, the load for driving included in the load 11 is stopped, so the load current is small. Therefore, even if the relay 12 is switched to the OFF state to diagnose the battery 10, the power supply unit 14 can maintain the power supply to the other loads 11. Therefore, the abnormality determination device 1 can check whether the relay 12 is switched to the OFF state while suppressing an increase in processing while the vehicle is running.

[0058] Third Embodiment In a third embodiment, an example will be described in which it is determined whether or not to switch the relay 12 to the off state when it is determined that the power reserve of the power supply unit 14 is equal to or greater than a predetermined power reserve. Note that the configuration of the third embodiment is the same as the configuration shown in FIG. 1 described in the first embodiment, and therefore will be described with reference to FIG. 1.

[0059] In the third embodiment, the second control unit 3 determines whether the power supply unit 14 has a predetermined margin or more, and outputs a diagnostic command if it determines that the power supply unit 14 has a margin or more. The second control unit 3 calculates, for example, the ratio of the current output current to the peak output current of the power supply unit 14 under normal conditions. If the calculated ratio is less than the predetermined ratio, the second control unit 3 determines that the power supply unit 14 has a margin or more than the predetermined margin, and if the calculated ratio is greater than the predetermined ratio, the second control unit 3 determines that the power supply unit 14 has a margin or less than the predetermined margin.

[0060] When the second control unit 3 determines that the power reserve of the power supply unit 14 is less than a predetermined power reserve, it suppresses the power supply from the power supply unit 14 to the load 11 and then outputs a diagnostic command. The second control unit 3 suppresses the power supply from the power supply unit 14 to the load 11, for example, by stopping some of the loads 11 that are in operation. Note that the operation of the first control unit 2 is the same as in the first embodiment.

[0061] The second control unit 3 starts the processing shown in Fig. 6 when the vehicle 100 switches to the parking state. In step S61, the second control unit 3 determines whether the vehicle has switched to the starting state. The second control unit 3 repeats the processing of step S61 until the vehicle has switched to the starting state. If the second control unit 3 determines that the vehicle has switched to the starting state, the second control unit 3 determines in step S62 whether the power supply from the power supply unit 14 has started. The second control unit 3 repeats the processing of step S62 until it determines that the power supply from the power supply unit 14 has started.

[0062] If the second control unit 3 determines that power supply from the power supply unit 14 has started, it determines in step S63 whether the remaining power from the power supply unit 14 is equal to or greater than a predetermined remaining power. If the second control unit 3 determines that the remaining power from the power supply unit 14 is equal to or greater than the predetermined remaining power, it outputs a diagnostic command in step S64.

[0063] If the second control unit 3 determines that the remaining power from the power supply unit 14 is less than a predetermined remaining power, in step S65, it suppresses the power supply from the power supply unit 14 to the load 11, and then in step S64, it outputs a diagnostic command.

[0064] After outputting the diagnostic command, the second control unit 3 determines whether or not the diagnostic result has been received from the first control unit 2 in step S66. The second control unit 3 repeats the process of step S66 until the diagnostic result is received. If the second control unit 3 determines that the diagnostic result has been received, the process proceeds to step S67. If the second control unit 3 suppressed the power supply in step S65, the second control unit 3 cancels the suppression of the power supply in step S67. Note that if the second control unit 3 has not performed the process of step S65, the second control unit 3 proceeds to step S68 without changing the state of the power supply in step S67. In step S68, the second control unit 3 determines whether or not the relay 12 is normal based on the diagnostic result. If the second control unit 3 determines that the relay 12 is normal, the second control unit 3 outputs information indicating that the diagnosis is completed to an external device in step S69. If the second control unit 3 determines that the relay 12 is not normal, the second control unit 3 performs an abnormality response process in step S70. The abnormality response process is, for example, a process of notifying an external device that an abnormality has occurred. After step S69 or step S70, the second control unit 3 ends the process shown in FIG.

[0065] As described above, the abnormality determination device 1 of the third embodiment checks whether the relay 12 should be switched to the OFF state when it is determined that the power reserve of the power supply unit 14 is equal to or greater than a predetermined power reserve. Therefore, the abnormality determination device 1 can easily prevent a shortage of power supply to the load 11 due to the relay 12 being switched to the OFF state.

[0066] Furthermore, when the abnormality determination device 1 determines that the remaining capacity of the power supply unit 14 is less than a predetermined remaining capacity, it suppresses the power supply from the power supply unit 14 to the load 11 and then checks whether the relay 12 is switched to the OFF state. Therefore, the abnormality determination device 1 can easily prevent a shortage of power supply to the load 11 by switching the relay 12 to the OFF state.

[0067] In the fourth embodiment, an example will be described in which it is determined whether the relay 12 is switched to the off state in the parking state. 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.

[0068] 7 discloses an abnormality determination device 601 included in a vehicle 600. In this embodiment, the vehicle 600 is an automobile equipped with a high-voltage battery 631 that is a drive source for a traction motor, and is, for example, a plug-in hybrid automobile, an electric automobile, or the like. The vehicle 600 switches between a starting state and a parking state. The starting state is when the start switch of the vehicle 600 is in an on state. The parking state is when the start switch of the vehicle 600 is in an off state. In this embodiment, the start switch is a power switch.

[0069] The vehicle 600 includes a battery 10 , a load 11 , a relay 12 , a battery case 13 , a power supply unit 614 , current detection units 15 and 16 , a first power path 21 , a second power path 22 , and a branch path 23 .

[0070] The power supply unit 614 is provided outside the battery case 13. The power supply unit 614 is electrically connected to a branch path 23 branching from the second power path 22. The output voltage of the power supply unit 614 is applied to the branch path 23. The power supply unit 614 supplies power to the load 11 via the branch path 23 and the second power path 22. The power supply unit 614 has a high-voltage battery 631 and a DCDC converter 632. The output voltage of the high-voltage battery 631 when fully charged is higher than the output voltage of the battery 10 when fully charged. The DCDC converter 632 performs a conversion operation to convert and output a voltage input from the high-voltage battery 631. The conversion operation is a step-down operation. The output voltage of the DCDC converter 632 is applied to the branch path 23.

[0071] The second control unit 3 controls the power supply unit 614 (specifically, the DCDC converter 632) via the power supply control unit 4. The second control unit 3 starts the power supply from the power supply unit 614 by causing the DCDC converter 632 to perform a conversion operation. The second control unit 3 stops the power supply from the power supply unit 614 by stopping the conversion operation by the DCDC converter 632.

[0072] The second control unit 3 starts the power supply from the power supply unit 614 when the vehicle 600 switches to the start state, and stops the power supply from the power supply unit 614 when the vehicle 600 switches to the parking state. However, when a determination condition is met in the parking state, the second control unit 3 starts the power supply from the power supply unit 614 and outputs a diagnostic command. The determination condition may be, for example, the passage of a predetermined determination time since switching to the parking state, the arrival of a predetermined determination time, or some other condition. The operation of the first control unit 2 is the same as in the first embodiment.

[0073] The second control unit 3 always performs the processing shown in FIG. 8 , for example. That is, the second control unit 3 resumes the processing shown in FIG. 8 immediately after completing the processing shown in FIG. 8 . The second control unit 3 determines whether or not the vehicle 600 is in a parked state in step S81. The second control unit 3 repeats the processing of step S81 until it determines that the vehicle 600 is in a parked state. If the second control unit 3 determines that the vehicle 600 is in a parked state, it determines whether or not a determination condition is met in step S82. The second control unit 3 repeats the processing of step S82 until it determines that the determination condition is met. If it determines that the determination condition is met, the second control unit 3 starts the supply of power from the power supply unit 614 in step S83. Then, the second control unit 3 outputs a diagnostic command in step S84.

[0074] After outputting the diagnostic command, the second control unit 3 determines in step S86 whether or not the diagnostic result has been received from the first control unit 2. The second control unit 3 repeats the process of step S86 until the diagnostic result has been received. If the second control unit 3 determines that the diagnostic result has been received, the second control unit 3 stops the power supply from the power supply unit 614 in step S87, and determines whether or not the relay 12 is normal based on the diagnostic result in step S88. If the second control unit 3 determines that the relay 12 is normal, the second control unit 3 outputs information indicating that the diagnosis has been completed to an external device in step S89. If the second control unit 3 determines that the relay 12 is not normal, the second control unit 3 performs an abnormality response process in step S90. The abnormality response process is, for example, a process of notifying an external device that an abnormality has occurred. After step S89 or step S90, the second control unit 3 ends the process shown in FIG. 8.

[0075] As described above, when the determination condition is met in the parking state, the abnormality determination device 601 of the fourth embodiment controls to start the power supply from the power supply unit 614 and switch the relay 12 to the off state, and determines whether the relay 12 has switched to the off state. Thus, in the parking state, the abnormality determination device 601 can check whether the relay 12 has switched to the off state while preventing the power supply to the load 11 from being interrupted.

[0076] <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.

[0077] In the first to third embodiments described above, the power supply unit 14 may be replaced with the power supply unit 614 described in the fourth embodiment.

[0078] In each of the above-described embodiments, the first control unit 2 and the second control unit 3 are configured to correspond to an example of a control unit, but this configuration is not limiting. For example, the control unit may be configured only by the first control unit 2 housed in the battery case 13. Alternatively, the control unit may be configured only by the second control unit 3 provided outside the battery case 13. In this case, the first control unit 2 may be omitted. Alternatively, the power supply control unit 4 may be included in the control unit.

[0079] In the second embodiment described above, only when it is not possible to confirm whether the relay 12 will be switched to the OFF state when the vehicle is switched to the starting state, the system checks whether the relay 12 will be switched to the OFF state when the vehicle is switched to the parking state. In contrast, the system may check whether the relay 12 will be switched to the OFF state when the vehicle is switched to the parking state, regardless of whether it is possible to confirm whether the relay 12 will be switched to the OFF state when the vehicle is switched to the starting state.

[0080] 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, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0081] REFERENCE SIGNS LIST 1... Abnormality determination device 2... First control unit (control unit) 3... Second control unit (control unit) 4... Power supply control unit 10... Battery 11... Load 12... Relay 13... Battery case 14... Power supply unit 15... Current detection unit 16... Current detection unit 21... First power path 22... Second power path 23... Branch path 31... Engine 32... Alternator 100... Vehicle 600... Vehicle 601... Abnormality determination device 614... Power supply unit 631... High voltage battery 632... DCDC converter

Claims

1. An abnormality determination device included in a vehicle having a battery that supplies power to a load, a relay provided between the battery and the load, a battery case that houses the battery and the relay, and a power supply unit provided outside the battery case, the abnormality determination device further comprising a control unit that controls the relay to an on state when the vehicle is in a starting state and a parked state, the control unit controlling the relay to be switched to an off state when power is being supplied from the power supply unit to the load, and determining whether the relay has been switched to the off state.

2. The abnormality determination device according to claim 1, wherein the control unit performs control to switch the relay to the off state when the vehicle switches to the start state and power supply from the power supply unit begins, and determines whether the relay has switched to the off state.

3. The abnormality determination device according to claim 2, wherein the control unit performs control to switch the relay to the off state when the vehicle switches to the starting state, power supply from the power supply unit begins, and the control unit determines that the shift range of the vehicle is the parking range, and determines whether the relay has switched to the off state.

4. The abnormality determination device according to claim 1, wherein the load includes a driving load that is stopped in the parked state, and the control unit, when the vehicle switches to the parked state, performs control to switch the relay to the off state while maintaining the power supply from the power supply unit, determines whether the relay has been switched to the off state, and, after making the determination, switches the relay to the on state and then stops the power supply from the power supply unit.

5. An abnormality determination device as claimed in any one of claims 1 to 4, wherein the control unit, when determining that the power supply unit has a predetermined margin of power or more, controls the relay to be switched to an off state and determines whether the relay has been switched to an off state.

6. An abnormality determination device as claimed in any one of claims 1 to 4, wherein when the control unit determines that the margin of the power supply unit is less than a predetermined margin of power, the control unit suppresses the power supply from the power supply unit to the load, and then performs control to switch the relay to an off state, and determines whether the relay has been switched to an off state.

7. The abnormality determination device according to claim 1, wherein the control unit performs control to start the power supply from the power supply unit in the parked state and to switch the relay to the off state, and determines whether the relay has been switched to the off state.

Images