Anomaly detection device and anomaly detection method

Abstract

To provide an abnormality detection device and an abnormality detection method, capable of suitably detecting abnormality of voltage in a power path to which two power supply units are connected.SOLUTION: An abnormality detection device 70 is used for a power supply system 100 including a first power supply unit 90, a second power supply unit 93, a first conducting path 1 and a second conducting path 2 that are paths for transferring power between the first power supply unit 90 and the second power supply unit 93, and a relay 10 that changes over between a state of permitting electric conduction between the first conducting path 1 and the second conducting path 2 and a state of cutting off electric conduction between the first conducting path 1 and the second conducting path 2. The abnormality detection device 70 includes: a first voltage detection unit 50 for detecting first voltage V1 on the side of the first power supply unit 90 of the relay 10 in the first conducting path 1 and the second conducting path 2; a second voltage detection unit 51 for detecting second voltage V2 on the side of the second power supply unit 93 of the relay 10 in the first conducting path 1 and the second conducting path 2; and a detection unit 30B for detecting abnormality on the basis of the first voltage V1 and the second voltage V2 in the case that the relay 10 is in the cut-off state.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to an abnormality detection device and an abnormality detection method. [Background technology]

[0002] Patent Document 1 discloses an in-vehicle power supply device that supplies power from a power storage unit that generates a relatively high voltage to a power storage unit that generates a relatively low voltage. This in-vehicle power supply device can protect the power storage unit by turning off a switch unit when the power storage unit that generates a relatively low voltage is reverse-connected or in an open state where it is not connected. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-129951 A [Patent Document 2] Patent No. 6729390 [Patent Document 3] JP 2019-83393 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology of Patent Document 1 can detect an abnormality in one power storage unit, but is not intended to detect an abnormality in the other power storage unit. However, in reality, there is a possibility that each power storage unit may be in an open state. Furthermore, when attempting to detect an abnormality in each power storage unit, it is necessary to avoid a situation in which the output voltage of each power storage unit prevents detection of the voltage of the other power storage unit.

[0005] The present disclosure has been completed based on the above-mentioned circumstances, and aims to provide an abnormality detection device and an abnormality detection method that are capable of effectively detecting voltage abnormalities in a power path to which two power supply units are connected. [Means for solving the problem]

[0006] An anomaly detection device according to the present disclosure includes: An abnormality detection device for use in a power supply system having a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path, the abnormality detection device detecting an abnormality, a first voltage detection unit that detects a first voltage on the first power supply unit side of the power path relative to the relay; a second voltage detection unit that detects a second voltage on the second power supply unit side of the power path relative to the relay; a detection unit that detects an abnormality based on the first voltage and the second voltage when the relay is in the interrupted state; has.

[0007] An anomaly detection method according to the present disclosure includes: An abnormality detection method for detecting an abnormality in a power supply system having a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path, the method comprising: a first operation of the control unit switching the relay to the interrupted state; A second operation in which a first voltage detection unit detects a first voltage on a side of the first power supply unit in the power path relative to the relay, after at least the first operation; a third operation in which a second voltage detection unit detects a second voltage on a side of the second power supply unit than the relay in the power path after at least the first operation; a fourth operation in which a detection unit detects an abnormality based on the first voltage and the second voltage in the interrupted state after the second operation and the third operation are executed; Includes. Effect of the Invention

[0008] According to the present disclosure, it is possible to effectively detect a voltage abnormality in a power path to which two power supply units are connected. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a power supply system provided with an abnormality detection device according to a first embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing the configuration of the abnormality detection device of the first embodiment. [Diagram 3] FIG. 3 is a flowchart showing the procedure of the abnormality detection method in the abnormality detection device of the first embodiment. [Figure 4] FIG. 4 is a timing chart showing the operating states of the first relay unit and the second relay unit and the transitions of the first voltage and the second voltage. [Diagram 5] FIG. 5 is a schematic diagram showing a part of the configuration of an abnormality detection device according to another embodiment. [Figure 6] FIG. 6 is a timing chart showing the operating states of the first relay unit and the second relay unit and the transitions of the first voltage and the second voltage in another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The following describes exemplary embodiments of the present disclosure. The following features [1] to [7] may be combined in any manner that is not inconsistent.

[0011] [1] The abnormality detection device disclosed herein is used in a power supply system to detect an abnormality. The power supply system has a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path. The abnormality detection device has a first voltage detection unit, a second voltage detection unit, and a detection unit. The first voltage detection unit detects a first voltage on the power path that is closer to the first power supply unit than the relay. The second voltage detection unit detects a second voltage on the power path that is closer to the second power supply unit than the relay. The detection unit detects the abnormality based on the first voltage and the second voltage when the relay is in a cut-off state.

[0012] The abnormality detection device of the above [1] can cut off the power path to the first power supply side and the second power supply side by turning off the relay, so that the voltage of the first power supply side and the voltage of the second power supply side are not transmitted to the power path on the opposite side of the relay. This makes it possible to detect the voltage in each of the power paths on both sides of the relay with good accuracy.

[0013] [2] The abnormality detection device according to [1] above has a control unit that controls the relay, and the control unit can periodically switch the relay between an open state and a cut-off state.

[0014] The anomaly detection device described in [2] above is capable of detecting anomalies in detail without any time lag from the point in time when an anomaly occurs in the power line.

[0015] [3] The abnormality detection device according to [1] or [2] above has a control unit that controls the relay, and the control unit can maintain the cut-off state when the detection unit detects an abnormality.

[0016] The abnormality detection device described in [3] above can prevent an abnormality occurring in one power path from propagating to the other power path.

[0017] [4] In the abnormality detection device of [1] or [2] above, a control unit is provided which controls the relay, and when the detection unit detects an abnormality, the control unit can at least either notify the outside or store the abnormality while maintaining an acceptable state.

[0018] The abnormality detection device described in [4] above can continue to supply power to the conductive path on one side by maintaining the relay in an allowable state when it is necessary to supply power to the conductive path on one side even if an abnormality occurs in the power path on one side. Since the device is configured to notify the outside, it can notify a state in which power is being supplied to the conductive path on one side despite an abnormality in the conductive path on one side. Furthermore, by having the control unit memorize the occurrence of a state in which power is being supplied to the conductive path on one side despite an abnormality in the conductive path on one side, it is possible to easily refer to the history of abnormal states in the conductive path during maintenance.

[0019] [5] The abnormality detection device according to any one of [2] to [4] above, further comprising a fault detection device. The fault detection device is capable of detecting a fault state in which the relay is maintained in an allowable state when the control unit is controlling the relay to be in an interrupted state, and a normal state in which the relay is maintained in an interrupted state when the control unit is controlling the relay to be in an interrupted state. The detection unit can detect an abnormality based on the first voltage and the second voltage when the control unit is controlling the relay to be in an interrupted state, on condition that the fault detection device detects the normal state.

[0020] The abnormality detection device described in [5] above can distinguish between a relay failure and an abnormality in the power path, thereby further improving the reliability of the detection of an abnormality in the power path by the detection unit.

[0021] [6] The abnormality detection method disclosed herein is used in a power supply system to detect an abnormality. The power supply system includes a first power supply unit, a second power supply unit, a power path that transmits power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path. The abnormality detection method includes a first operation, a second operation, a third operation, and a fourth operation. In the first operation, the control unit switches the relay to a cut-off state. In the second operation, at least after the first operation, the first voltage detection unit detects a first voltage on the first power supply unit side of the relay in the power path. In the third operation, at least after the first operation, the second voltage detection unit detects a second voltage on the second power supply unit side of the relay in the power path. In the fourth operation, after the second operation and the third operation are performed, the detection unit detects an abnormality based on the first voltage and the second voltage in the cut-off state.

[0022] The abnormality detection method described above in [6] can cut off the power path to the first power supply side and the second power supply side by turning off the relay, so that the voltages of the first power supply side and the second power supply side are not transmitted to the power path on the opposite side of the relay. This makes it possible to detect the voltages in the power paths on both sides of the relay with good accuracy.

[0023] [7] An abnormality detection program for use in a power supply system having a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path, A first step of causing a control unit to perform an operation of switching the relay to the interrupted state; a second step of causing a detection unit to perform an operation of detecting an abnormality based on a first voltage on the first power supply side of the relay in the power path during the interrupted state and a second voltage on the second power supply side of the relay in the power path during the interrupted state; Anomaly detection programs, including:

[0024] The abnormality detection program in [7] above can cut off the power path to the first power supply side and the second power supply side by turning off the relay, so that the voltages of the first power supply side and the second power supply side are not transmitted to the power path on the opposite side of the relay. This makes it possible to properly detect the voltages in the power paths on both sides of the relay.

[0025] [Details of the embodiment of the present disclosure]

[0026] <Embodiment 1> [Power supply system configuration] 1 illustrates a power supply system 100 provided with an abnormality detection device 70 according to the first embodiment. The power supply system 100 is used as a power supply for operating loads 92, 94, etc. of a vehicle in which the power supply system 100 is installed. The power supply system 100 has a first power supply unit 90, a second power supply unit 93, a first conductive path 1 which is a power path, a second conductive path 2 which is a power path, a relay 10, and the abnormality detection device 70.

[0027] The first power supply unit 90 and the second power supply unit 93 are configured as DC power supplies such as lithium ion batteries and lead storage batteries. The output voltage of the first power supply unit 90 and the second power supply unit 93 is, for example, 12 V. One end of the first conductive path 1 is electrically connected to a high potential terminal of the first power supply unit 90. A load 92 is electrically connected to one end of the first conductive path 1 so as to be in parallel with the first power supply unit 90. The other end of the first conductive path 1 is electrically connected to one end of the relay 10. One end of the second conductive path 2 is electrically connected to a high potential terminal of the second power supply unit 93. A load 94 is electrically connected to one end of the second conductive path 2 so as to be in parallel with the second power supply unit 93. The other end of the second conductive path 2 is electrically connected to the other end of the relay 10. The first conductive path 1 and the second conductive path 2 are paths for transmitting power between the first power supply unit 90 and the second power supply unit 93.

[0028] In the present disclosure, "electrically connected" preferably means a configuration in which the connection objects are connected in a mutually conductive state (a state in which a current can flow) so that the potentials of both connection objects are equal. However, this is not limited to this configuration. For example, "electrically connected" may mean a configuration in which the two connection objects are connected in a state in which the two connection objects can be conductive with an electric component interposed between them.

[0029] The load 92 is configured to operate electrical components by receiving power supply from the first power supply unit 90. The load 94 has the same configuration and function as the load 92. The power supply system 100 is configured as a system that, when an abnormality occurs in the load 92, operates the load 94 instead of the load 92, so that the function of the load 92 can be maintained by the load 94 even when the load 92 is abnormal.

[0030] The relay 10 is disposed between a first power supply unit 90 and a second power supply unit 93. The relay 10 switches between an allowable state in which the first conductive path 1 and the second conductive path 2 are allowed to pass current and a cut-off state in which the first conductive path 1 and the second conductive path 2 are cut off. As shown in FIG. 2, the relay 10 has a configuration in which a first relay unit 10C and a second relay unit 10F are electrically connected in parallel. The first relay unit 10C is configured with two switch elements 10A and 10B connected in series in different orientations. The second relay unit 10F is configured with two switch elements 10D and 10E connected in series in different orientations.

[0031] In the first embodiment, a case where each of the first relay unit 10C and the second relay unit 10F is configured by two N-channel MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) will be described as a representative example. When each of the switch elements 10A and 10B of the first relay unit 10C is configured by an N-channel MOSFET, the sources of these switch elements 10A and 10B are electrically connected to each other via a first intermediate conductive path 4. The drain of the switch element 10A is connected to an end of the first conductive path 1, and the drain of the switch element 10B is arranged to be connected to the second conductive path 2. The first intermediate conductive path 4 is electrically connected to the fault detection device 30A via a first signal line 21.

[0032] When each of the switch elements 10D, 10E of the second relay unit 10F is configured by an N-channel MOSFET, the sources of these switch elements 10D, 10E are electrically connected to each other via the second intermediate conductive path 5. The drain of the switch element 10D is connected to an end of the first conductive path 1, and the drain of the switch element 10E is arranged to be connected to the second conductive path 2. The second intermediate conductive path 5 is electrically connected to the fault detection device 30A via the second signal line 22. As a result, the first relay unit 10C and the second relay unit 10F can be configured to have two MOSFETs arranged in series in a so-called butted state (an arrangement in which the body diodes are oriented in opposite directions to each other).

[0033] The gates of the switch elements 10A, 10B, 10D, and 10E are electrically connected to the control unit 30. Specifically, the gates of the switch elements 10A and 10B are electrically connected to the control unit 30 via a first wire 6. E The gate of the relay unit 10C is electrically connected to the control unit 30 via the second electric wire 7. With this configuration, the first relay unit 10C and the second relay unit 10F can be individually controlled by the control unit 30.

[0034] [Configuration of anomaly detection device] The abnormality detection device 70 includes a first voltage detection unit 50, a second voltage detection unit 51, a control unit 30, a fault detection device 30A, and a detection unit 30B.

[0035] The first voltage detection unit 50 is provided on the first conductive path 1, which is an electric power path located closer to the first power supply unit 90 than the relay 10. The first voltage detection unit 50 detects a first voltage V1 at a predetermined position on the first conductive path 1 (a position closer to the first power supply unit 90 than the relay 10) and provides a detection value corresponding to the first voltage V1 to the detection unit 30B. The detection unit 30B can identify the voltage value at the predetermined position on the first conductive path 1 based on the detection value input from the first voltage detection unit 50.

[0036] The second voltage detection unit 51 is provided on the second conductive path 2, which is an electric power path located closer to the second power supply unit 93 than the relay 10. The second voltage detection unit 51 detects the second voltage V2 at a predetermined position on the second conductive path 2 (a position closer to the second power supply unit 93 than the relay 10), and provides the detection value according to the second voltage V2 to the detection unit 30B. The detection unit 30B can identify the voltage value at the predetermined position on the second conductive path 2 based on the detection value input from the second voltage detection unit 51.

[0037] The control unit 30 is mainly composed of, for example, a microcomputer, and has an arithmetic device such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), an A / D converter, etc. The control unit 30 performs an on control to provide an on signal Son to each gate of the switch elements 10A, 10B, 10D, and 10E via the first electric wire 6 and the second electric wire 7. Then, the relay 10 (the switch elements 10A, 10B, 10D, and 10E) is turned on and enters an allowable state in which conduction between the first conductive path 1 and the second conductive path 2 is permitted. The control unit 30 performs an off control to provide an off signal Soff to each gate of the switch elements 10A, 10B, 10D, and 10E via the first electric wire 6 and the second electric wire 7. Then, the relay 10 (the switch elements 10A, 10B, 10D, and 10E) is turned off and enters an interrupted state. In the interrupted state, the relay 10 does not pass current in either direction (i.e., toward the first conductive path 1 and the second conductive path 2), and in this state, the current between the first conductive path 1 and the second conductive path 2 is completely interrupted. In other words, the control unit 30 is configured to be able to control the relay 10.

[0038] Furthermore, the control unit 30 is configured to periodically switch the switch elements 10A, 10B, 10D, and 10E of the relay 10 between an open state and an open state when the relay 10 does not have a short circuit failure or an open circuit failure.

[0039] The fault detection device 30A is provided in, for example, the control unit 30. The fault detection device 30A is configured to be able to detect faults in the switch elements 10A, 10B, 10D, and 10E of the relay 10. The fault detection device 30A performs a fault detection operation, for example, when a start switch (e.g., an ignition switch) (not shown) is turned on. The fault detection device 30A obtains a third voltage V3, which is the voltage of the first intermediate conductive path 4, via a first signal line 21, and obtains a fourth voltage V4, which is the voltage of the second intermediate conductive path 5, via a second signal line 22.

[0040] The fault detection device 30A detects the fault of the switch elements 10A, 10B based on the on / off control state of the switch elements 10A, 10B and the third voltage V3 while the control unit 30 turns on the switch elements 10D, 10E. For example, the fault detection device 30A performs an open fault detection process to detect the open fault of the switch elements 10A, 10B based on the third voltage V3. The open fault is a fault in which the switch element does not switch from off to on. If the third voltage V3 is not the same as the voltage of the first conductive path 1 or the second conductive path 2 despite the output of the on signal Son from the control unit 30 to the switch elements 10A, 10B, the fault detection device 30A determines that both the switch elements 10A, 10B have an open fault. This state is a fault state in which the relay 10 is maintained in an interrupted state while the control unit 30 controls the relay 10 to be in an allowable state. In this way, the fault detection device 30A detects the open fault of the switch elements 10A, 10B. For example, when the failure detection device 30A detects an open failure in the switch elements 10A and 10B, it outputs an open failure signal Sop to the detection unit 30B.

[0041] When the control unit 30 outputs an on signal Son to the switching elements 10A, 10B, the fault detection device 30A does not detect an open fault in the switching elements 10A, 10B if the third voltage V3 is the same as the voltage of the first conductive path 1 or the second conductive path 2. This state is a normal state in which the relay 10 is maintained in the permissible state while the control unit 30 is performing control to put the relay 10 into the permissible state. In this case, the fault detection device 30A does not output an open fault signal Sop to the detection unit 30B.

[0042] The fault detection device 30A also performs a short circuit fault detection process to detect a short circuit fault in the switch elements 10A and 10B based on the third voltage V3. A short circuit fault is a fault in which the switch element does not switch from on to off. If the third voltage V3 is the same as the voltage of the first conductive path 1 or the second conductive path 2 despite the output of an off signal S0ff from the control unit 30 to the switch elements 10A and 10B, the fault detection device 30A determines that at least one of the switch elements 10A and 10B has a short circuit fault. This state is a fault state in which the relay 10 is maintained in an allowable state when the control unit 30 controls the relay 10 to be in an interrupted state. In this way, the fault detection device 30A detects a short circuit fault in the switch elements 10A and 10B. For example, when the fault detection device 30A detects a short circuit fault in the switch elements 10A and 10B, it outputs a short circuit fault signal Ssh to the detection unit 30B.

[0043] When the control unit 30 outputs an off signal Soff to the switching elements 10A, 10B, and the third voltage V3 is not the same as the voltage of the first conducting path 1 or the second conducting path 2, the fault detection device 30A does not detect a short circuit fault in the switching elements 10A, 10B. This state is a normal state in which the relay 10 is maintained in the cut-off state while the control unit 30 controls the relay 10 to be in the cut-off state. In this case, the fault detection device 30A does not output a short circuit fault signal Ssh to the detection unit 30B. In this way, the fault detection device 30A is capable of detecting a fault state and a normal state in the relay 10.

[0044] The fault detection device 30A detects faults in the switch elements 10D, 10E based on the on / off control state of the switch elements 10D, 10E and the fourth voltage V4 while turning on the switch elements 10A, 10B using the control unit 30. The method of detecting faults in the switch elements 10D, 10E is the same as the method of detecting faults in the switch elements 10A, 10B described above, and therefore will not be described here. When the fault detection device 30A detects a short fault in the switch elements 10D, 10E, it outputs a short fault signal Ssh to the detection unit 30B, and when it detects an open fault in the switch elements 10D, 10E, it outputs an open fault signal Sop to the detection unit 30B.

[0045] The detection unit 30B is provided in, for example, the control unit 30. The detection unit 30B is configured to receive the first voltage V1 in the first conductive path 1 and the second voltage V2 in the second conductive path 2 from the first voltage detection unit 50 and the second voltage detection unit 51, respectively. The detection unit 30B detects an abnormality based on the first voltage and the second voltage when the control unit 30 controls the relay 10 to be in the cut-off state, on the condition that the fault detection device 30A detects a normal state. The detection unit 30B detects an abnormality such as a ground fault occurring in each of the first conductive path 1 and the second conductive path 2, a disconnection of the first power supply unit 90 from the first conductive path 1, or a disconnection of the second power supply unit 93 from the second conductive path 2, based on the first voltage V1 and the second voltage V2.

[0046] Specifically, if the difference between the first voltage V1 input from the first voltage detection unit 50 and the output voltage (12V) of the first power supply unit 90 is greater than or equal to a predetermined threshold, the detection unit 30B determines that the power path is in an abnormal state (i.e., detects an abnormality). Also, if the difference between the first voltage V1 input from the first voltage detection unit 50 and the output voltage of the first power supply unit 90 is less than a predetermined threshold, the detection unit 30B determines that the power path is in a normal state (i.e., does not detect an abnormality).

[0047] Furthermore, when the difference between the second voltage V2 input from the second voltage detection unit 51 and the output voltage (12V) of the second power supply unit 93 is equal to or greater than a predetermined threshold, the detection unit 30B determines that the power path is in an abnormal state (i.e., detects an abnormality). When the difference between the second voltage V2 input from the second voltage detection unit 51 and the output voltage of the second power supply unit 93 is less than a predetermined threshold, the detection unit 30B determines that the power path is in a normal state (i.e., does not detect an abnormality).

[0048] [Operation of anomaly detection device] An example of an anomaly detection method in which the anomaly detection device 70 detects an anomaly will be described.

[0049] First, the start switch is turned on (Yes in step S1). Then, the process proceeds to step S2, where the fault detection device 30A performs fault detection operations (open fault detection processing and short fault detection processing). If the start switch is not turned on in step S1 (No in step S1), the process shown in FIG. 3 is terminated.

[0050] In step S2, if the fault detection device 30A does not detect a short fault or an open fault in the switch elements 10A, 10B, 10D, and 10E (Yes in step S2), it does not output either the short fault signal Ssh or the open fault signal Sop to the detection unit 30B. Then, the process proceeds to step S3, in which the control unit 30 starts alternately outputting an on signal Son and an off signal Soff to the switch elements 10A, 10B, 10D, and 10E of the relay 10 at predetermined intervals. In this way, the control unit 30 periodically switches the relay 10 between an open state and a cut-off state.

[0051] In step S3, the control unit 30 periodically alternates between a first operation for switching the switch elements 10A, 10B, 10D, and 10E in the relay 10 to a cutoff state and an enabling operation for switching the switch elements 10A, 10B, 10D, and 10E to an enabling state. The first operation is a state in which the control unit 30 performs an OFF control for outputting an OFF signal Soff to the switch elements 10A, 10B, 10D, and 10E. This brings the source and drain of each of the switch elements 10A, 10B, 10D, and 10E into a cutoff state. The enabling operation is a state in which the control unit 30 performs an ON control for outputting an ON signal Son to the switch elements 10A, 10B, 10D, and 10E. This brings the source and drain of each of the switch elements 10A, 10B, 10D, and 10E into a conductive enabling state.

[0052] In step S2, when the fault detection device 30A detects a short circuit failure of the switch elements 10A, 10B, 10D, and 10E (No in step S2), the fault detection device 30A outputs a short circuit failure signal Ssh to the detection unit 30B. Then, the process in FIG. 3 is terminated. In step S2, when the fault detection device 30A detects an open circuit failure, the fault detection device 30A outputs an open circuit failure signal Sop to the detection unit 30B and terminates the process in FIG. 3. When the short circuit failure signal Ssh or the open circuit failure signal Sop is input, the detection unit 30B does not detect an abnormality. In other words, when the fault detection device 30A detects a short circuit failure of the relay 10 (i.e., an ON operation when controlled to be OFF), the detection unit 30B does not detect an abnormality. Note that the detection unit 30B may be configured to detect an abnormality when an open circuit failure occurs in either the first relay unit 10C or the second relay unit 10F and the other is not failed.

[0053] When the process proceeds to step S4, the control unit 30 determines whether or not the first operation is being performed. In step S4, if the control unit is not performing the first operation (i.e., the control unit is performing an on-control to output an on-signal Son to the switch elements 10A, 10B, 10D, and 10E; No in step S4), the process in FIG. 3 is terminated.

[0054] In step S4, if the control unit 30 is performing an off control of outputting an off signal Soff to the switch elements 10A, 10B, 10D, and 10E (Yes in step S4), the process proceeds to step S5. In step S5, the first voltage detection unit 50 executes a second operation of detecting a first voltage V1 at a position on the first conductive path 1 that is closer to the first power supply unit 90 than the relay 10. Specifically, in the second operation, the first voltage detection unit 50 detects the first voltage V1 at a predetermined position on the first conductive path 1 (a position on the first power supply unit 90 than the relay 10) and provides a detection value according to the first voltage V1 to the detection unit 30B.

[0055] Next, the process proceeds to step S6, where after the first operation, second voltage detection unit 51 executes a third operation in which it detects the second voltage V2 at a position on the second conductive path 2 closer to second power supply unit 93 than relay 10. Specifically, in the third operation, second voltage detection unit 51 detects the second voltage V2 at a predetermined position (a position on the second power supply unit 93 side than relay 10) on second conductive path 2, and provides a detection value corresponding to the second voltage V2 to detection unit 30B.

[0056] Next, after the second operation and the third operation are performed, the process proceeds to step S7, where the detection unit 30B performs a fourth operation of detecting an abnormality based on the first voltage V1 and the second voltage V2 in the cut-off state. In step S7, the detection unit 30B detects an abnormality based on the first voltage and the second voltage when the control unit 30 controls the relay 10 to be in the cut-off state in step S4, on the condition that the fault detection device 30A detects a normal state in step S2. In step S7, if the detection unit 30B determines that the difference between the first voltage V1 and the output voltage (12V) of the first power supply unit 90 is equal to or greater than a predetermined threshold, or the difference between the second voltage V2 and the output voltage (12V) of the second power supply unit 93 is equal to or greater than a predetermined threshold (Yes in step S7), the process proceeds to step S8. In step S8, the detection unit 30B determines that the power path is in an abnormal state (i.e., detects an abnormality). Then, the control unit 30 continues to output the off signal Soff to the switch elements 10A, 10B, 10D, and 10E. That is, the control unit 30 maintains the cut-off state when the detection unit 30B detects an abnormality. Then, the process in FIG. 3 ends.

[0057] When the detection unit 30B determines that the difference between the first voltage V1 and the output voltage of the first power supply unit 90 is less than the predetermined threshold value and that the difference between the second voltage V2 and the output voltage of the second power supply unit 93 is less than the predetermined threshold value (No in step S7), the process proceeds to step S9. When the process proceeds to step S9, the detection unit 30B determines that the power path is in a normal state (i.e., no abnormality is detected). Then, the control unit 30 outputs an on signal Son to the switch elements 10A, 10B, 10D, and 10E. That is, when the detection unit 30B does not detect an abnormality in the power path, the control unit 30 switches the relay 10 from the interrupted state to the permitted state. Then, the process in FIG. 3 ends.

[0058] [An example of the operation of an anomaly detection device] An example of the operation of the abnormality detection device 70 will be described with reference to FIG.

[0059] When the fault detection device 30A does not detect a fault in the switch elements 10A, 10B, 10D, and 10E, the control unit 30 starts outputting an on signal Son and an off signal Soff alternately to the switch elements 10A, 10B, 10D, and 10E at predetermined intervals.

[0060] As shown in FIG. 4, at time T1, the control unit 30 switches the signal output to the first relay unit 10C and the second relay unit 10F (switch elements 10A, 10B, 10D, and 10E) from the on signal Son to the off signal Soff. Between time T1 and time T2, the control unit 30 continues to output the off signal Soff to the switch elements 10A, 10B, 10D, and 10E. Between time T1 and time T2, the relay 10 is in an interruption state in which the current flow through the first conductive path 1 and the second conductive path 2 is interrupted (Yes in step S4 in FIG. 3). Between time T1 and time T2, the detection unit 30B executes the second to fourth operations to determine whether the power path is in an abnormal state or a normal state (steps S5 to S9 in FIG. 3).

[0061] Between time T1 and time T2, the first voltage V1 in the first conductive path 1 is the same as the output voltage (12 V) of the first power supply unit 90, and the second voltage V2 in the second conductive path 2 is the same as the output voltage (12 V) of the second power supply unit 93. That is, the difference between the first voltage V1 and the output voltage of the first power supply unit 90 is less than a predetermined threshold, and the difference between the second voltage V2 and the output voltage of the second power supply unit 93 is less than a predetermined threshold (No in step S7 in FIG. 3). In this case, the detection unit 30B determines that the power path is in a normal state (step S9 in FIG. 3).

[0062] Next, at time T2, the control unit 30 switches the signal output to the first relay unit 10C and the second relay unit 10F (switch elements 10A, 10B, 10D, 10E) from the off signal Soff to the on signal Son. Between time T2 and time T3, the relay 10 is in a permissive state that allows current to flow through the first conductive path 1 and the second conductive path 2 (No in step S4 in FIG. 3). Therefore, between time T2 and time T3, the second to fourth operations are not executed. That is, the detection unit 30B does not determine whether the power path is in an abnormal state or a normal state when in the permissive state.

[0063] Next, at time T3, the control unit 30 switches the signal output to the first relay unit 10C and the second relay unit 10F (switch elements 10A, 10B, 10D, and 10E) from the on signal Son to the off signal Soff. Between time T3 and time T4, the control unit 30 continues to output the off signal Soff to the switch elements 10A, 10B, 10D, and 10E. Between time T3 and time T4, the relay 10 is in an interruption state in which the current is interrupted through the first conductive path 1 and the second conductive path 2 (Yes in step S4 in FIG. 3). Between time T3 and time T4, the detection unit 30B executes the second to fourth operations to determine whether the power path is in an abnormal state or a normal state (steps S5 to S9 in FIG. 3).

[0064] Also, at time T3, the first voltage V1 in the first conductive path 1 changes from the same magnitude as the output voltage of the first power supply unit 90 to 0V. The second voltage V2 in the second conductive path 2 is the same as the output voltage (12V) of the second power supply unit 93 and does not change. At this time, the difference between the first voltage V1 and the output voltage of the first power supply unit 90 is equal to or greater than a predetermined threshold, and the difference between the second voltage V2 and the output voltage of the second power supply unit 93 is less than the predetermined threshold (Yes in step S7 in FIG. 3). Then, the detection unit 30B determines that the power path is in an abnormal state (step S8 in FIG. 3). In this way, the abnormality detection device 70 detects an abnormality in the power path. After time T4, the control unit 30 continues to output the off signal Soff to the first relay unit 10C and the second relay unit 10F (switch elements 10A, 10B, 10D, 10E). This prevents the abnormality occurring on the first conductive path 1 side from propagating to the second conductive path 2 side.

[0065] Next, the effects of this configuration will be illustrated.

[0066] The abnormality detection device 70 of the present disclosure is used in a power supply system 100 to detect an abnormality. The power supply system 100 includes a first power supply unit 90, a second power supply unit 93, a first conductive path 1, a second conductive path 2, and a relay 10. The first conductive path 1 and the second conductive path 2 are paths for transmitting power between the first power supply unit 90 and the second power supply unit 93. The relay 10 switches between an allowable state that allows the first conductive path 1 and the second conductive path 2 to pass current and a cut-off state that cuts off current to the first conductive path 1 and the second conductive path 2. The abnormality detection device 70 includes a first voltage detection unit 50, a second voltage detection unit 51, and a detection unit 30B. The first voltage detection unit 50 detects a first voltage V1 on the first conductive path 1 and the second conductive path 2, which is closer to the first power supply unit 90 than the relay 10. The second voltage detection unit 51 detects a second voltage V2 on the second power supply unit 93 side of the relay 10 in the first conductive path 1 and the second conductive path 2. The detection unit 30B detects an abnormality based on the first voltage V1 and the second voltage V2 when the relay 10 is in the interrupted state.

[0067] According to this configuration, by turning the relay 10 to an interrupted state, the first conductive path 1 and the second conductive path 2 can be separated to the first power supply unit 90 side and the second power supply unit 93 side. This makes it possible to prevent the voltages of the first power supply unit 90 and the second power supply unit 93 from being transmitted to the power path on the opposite side of the relay 10. This makes it possible to properly detect the voltages in the first conductive path 1 and the second conductive path 2 on both sides of the relay 10.

[0068] The abnormality detection device 70 of the present disclosure includes a control unit 30 that controls the relay 10, and the control unit 30 periodically switches the relay 10 between an open state and a cut-off state. With this configuration, it is easy to detect an abnormality without any time elapsing after an abnormality occurs in the first conductive path 1 and the second conductive path 2.

[0069] The abnormality detection device 70 of the present disclosure has a control unit 30 that controls the relay 10, and the control unit 30 maintains the interrupted state when the detection unit 30B detects an abnormality. With this configuration, it is possible to prevent an abnormality occurring in one power path from propagating to the other power path.

[0070] The abnormality detection device 70 of the present disclosure includes a fault detection device 30A. The fault detection device 30A can detect a fault state and a normal state. The fault state is a state in which the relay 10 is maintained in an allowable state when the control unit 30 controls the relay 10 to be in an interrupted state. The normal state is a state in which the relay 10 is maintained in an interrupted state when the control unit 30 controls the relay 10 to be in an interrupted state. The detection unit 30B detects an abnormality based on the first voltage V1 and the second voltage V2 when the control unit 30 controls the relay 10 to be in an interrupted state, on the condition that the fault detection device 30A detects the normal state. According to this configuration, a fault in the relay 10 and an abnormality in the first conductive path 1 and the second conductive path 2 can be distinguished from each other, and therefore the reliability of the detection of an abnormality in the first conductive path 1 and the second conductive path 2 by the detection unit 30B can be further improved.

[0071] The anomaly detection method of the present disclosure is used in a power supply system 100 to detect an anomaly. The power supply system 100 includes a first power supply unit 90, a second power supply unit 93, a first conductive path 1 and a second conductive path 2, and a relay 10. The first conductive path 1 and the second conductive path 2 are paths for transmitting power between the first power supply unit 90 and the second power supply unit 93. The relay 10 , No. The relay 10 is switched between an allowable state that allows the first conductive path 1 and the second conductive path 2 to pass current and a cut-off state that cuts off the current through the first conductive path 1 and the second conductive path 2. The abnormality detection method includes a first operation, a second operation, a third operation, and a fourth operation. In the first operation, the control unit 30 switches the relay 10 to the cut-off state. In the second operation, after the first operation, the first voltage detection unit 50 detects a first voltage V1 on the first conductive path 1 and the second conductive path 2, which is closer to the first power supply unit 90 than the relay 10. In the third operation, after the first operation, the second voltage detection unit 51 detects a second voltage V2 on the first conductive path 1 and the second conductive path 2, which is closer to the second power supply unit 93 than the relay 10. In the fourth operation, after the second operation and the third operation are performed, the detection unit 30B detects an abnormality based on the first voltage V1 and the second voltage V2 in the cut-off state.

[0072] According to this configuration, by turning the relay 10 to an interrupted state, the first conductive path 1 and the second conductive path 2 can be separated to the first power supply unit 90 side and the second power supply unit 93 side. This makes it possible to prevent the voltages of the first power supply unit 90 and the second power supply unit 93 from being transmitted to the power path on the opposite side of the relay 10. This makes it possible to properly detect the voltages in the first conductive path 1 and the second conductive path 2 on both sides of the relay 10.

[0073] <Other embodiments>

[0074] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. 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] In the first embodiment, when the detection unit 30B detects an abnormality, the control unit 30 maintains the cut-off state. However, when the detection unit detects an abnormality, the control unit may maintain the permissible state and notify and store the abnormality to the outside. Specifically, as shown in FIG. 5, when the detection unit 30B detects an abnormality, the abnormality detection device 170 outputs a notification signal N indicating that the detection unit has detected an abnormality from the control unit 130 to the external ECU 200. When the notification signal N is input to the external ECU 200, the notification unit 200A connected to the external ECU 200 generates a sound. For example, a buzzer or a speaker is used for the notification unit 200A. This notifies the user of the vehicle that the power path is in an abnormal state. Furthermore, at this time, the detection unit 30B stores abnormality information M indicating that the power path has become abnormal in the RAM 130C of the control unit 130. Note that an LED may be used for the notification unit. In this case, when the notification signal is input to the external ECU, , outside The notification unit connected to the ECU emits light.

[0076] For example, as shown in FIG. 6, at time T11, the control unit 130 switches the signal output to the first relay unit 10C and the second relay unit 10F from the on signal Son to the off signal Soff. If the first voltage V1 changes from the same magnitude as the output voltage of the first power supply unit 90 to 0V at this timing, the detection unit 30B determines that the power path is in an abnormal state between time T11 and time T12. After that, at time T12, the control unit 130 switches the signal output to the first relay unit 10C and the second relay unit 10F from the off signal Soff to the on signal Son. Then, the conduction between the first conductive path 1 and the second conductive path 2 is permitted. In this case, for example, a resistance component is interposed between the first conductive path 1 and the second conductive path 2. Then, a current can be passed from the second conductive path 2 side to the first conductive path 1 side without dropping the second voltage V2 of the second conductive path 2 to 0V.

[0077] According to this configuration, when it is necessary to supply power to the conductive path on one side even if an abnormality occurs in the power path on one side, the relay can be maintained in an allowable state to continue supplying power to the conductive path on one side. Furthermore, by outputting a notification signal N to the external ECU 200, a state in which power is being supplied to the conductive path on one side despite an abnormality in the conductive path on one side can be notified using the notification unit 200A. Furthermore, by storing abnormality information M in the RAM 130C or the like of the control unit 130, which indicates that a state has occurred in which power is being supplied to the conductive path on one side despite an abnormality in the conductive path on one side, it is possible to easily refer to the history of abnormal states in the conductive path during maintenance. Note that a configuration may be adopted in which only one of outputting a notification signal to the external ECU and storing abnormality information in the RAM is performed.

[0078] In the first embodiment, a configuration in which the first relay unit 10C and the second relay unit 10F are connected in parallel has been described, but the number of relay units connected in parallel may be three or more depending on the magnitude of the current flowing through the power path. Also, in the first embodiment, the use of a MOSFET for the relay 10 has been disclosed, but a mechanical relay switch may also be used for the relay.

[0079] In the first embodiment, the control unit 30 is mainly configured with a microcomputer, but it may be realized by a plurality of hardware circuits other than a microcomputer. Also, at least one of the fault detection device and the detection unit may be provided separately from the control unit.

[0080] In the first embodiment, the output voltage of the first power supply unit 90 and the second power supply unit 93 is disclosed as 12 V, but the output voltage of the first power supply unit and the second power supply unit is not limited to this voltage. In addition, the output voltage of the first power supply unit and the second power supply unit do not have to be the same.

[0081] In the first embodiment, when the relay 10 does not have a short circuit fault or an open circuit fault, the control unit 30 periodically switches the switch elements 10A, 10B, 10D, and 10E between an allowable state and a cut-off state. However, the present invention is not limited to this, and the relay may be periodically switched between an allowable state and a cut-off state when, for example, the vehicle is running, parked, or stopped, the start switch is in an off state, etc.

[0082] In the first embodiment, the operations are performed in the order of the first operation, the second operation, and the third operation, but the operations may be performed in the order of the first operation, the third operation, and the second operation. That is, the first voltage detection unit may perform the second operation at least after the first operation, and the second voltage detection unit may perform the third operation at least after the first operation. [Explanation of symbols]

[0083] 1...First conductive path (power path) 2...Second conductive path (power path) 4...First intermediate conductive path 5...Second intermediate conductive path 10…Relay 10A, 10B, 10D, 10E...Switch elements 10C…First relay section 10F…Second Relay Section 21…First signal line 22...Second signal line 30,130…Control unit 30A…Fault detection device 30B…Detection section 50...First voltage detection unit 51...Second voltage detection unit 70,170…Anomaly detection device 90...1st power supply section 92,94…Load 93…Second power supply section 100…Power supply system 130C…RAM 200...External ECU 200A…Notification section M…Abnormal information N: Announcement signal Sop…Open fault signal Ssh...Short circuit fault signal Soff...Off signal Son…On signal V1…First voltage V2: Second voltage V3…Third voltage V4…4th voltage

Claims

1. An abnormality detection device for use in a power supply system having a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path, the abnormality detection device detecting an abnormality, a first voltage detection unit that detects a first voltage on the first power supply unit side of the power path relative to the relay; a second voltage detection unit that detects a second voltage on the second power supply unit side of the power path relative to the relay; a detection unit that detects an abnormality based on the first voltage and the second voltage when the relay is in the interrupted state; A control unit that controls the relay; having The control unit is an abnormality detection device that periodically switches the relay between the permitting state and the blocking state.

2. An abnormality detection device for use in a power supply system having a first power supply unit, a second power supply unit, a power path which is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay which switches between an allowable state which allows current to flow through the power path and a cut-off state which cuts off current to the power path, the abnormality detection device detecting an abnormality, a first voltage detection unit that detects a first voltage on the first power supply unit side of the power path relative to the relay; a second voltage detection unit that detects a second voltage on the second power supply unit side of the power path relative to the relay; a detection unit that detects an abnormality based on the first voltage and the second voltage when the relay is in the interrupted state; A control unit that controls the relay; a fault detection device capable of detecting a fault state in which the relay is maintained in the permissible state when the control unit is performing control to put the relay in the cut-off state, and a normal state in which the relay is maintained in the cut-off state when the control unit is performing control to put the relay in the cut-off state; having The control unit maintains the interrupted state when the detection unit detects an abnormality, The detection unit is an abnormality detection device that detects an abnormality based on the first voltage and the second voltage when the control unit is controlling the relay to be in the cut-off state, on the condition that the fault detection device detects the normal state.

3. An abnormality detection device for use in a power supply system having a first power supply unit, a second power supply unit, a power path which is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay which switches between an allowable state which allows current to flow through the power path and a cut-off state which cuts off current to the power path, the abnormality detection device detecting an abnormality, a first voltage detection unit that detects a first voltage on the first power supply unit side of the power path relative to the relay; a second voltage detection unit that detects a second voltage on the second power supply unit side of the power path relative to the relay; a detection unit that detects an abnormality based on the first voltage and the second voltage when the relay is in the interrupted state; A control unit that controls the relay; a fault detection device capable of detecting a fault state in which the relay is maintained in the permissible state when the control unit is performing control to put the relay in the cut-off state, and a normal state in which the relay is maintained in the cut-off state when the control unit is performing control to put the relay in the cut-off state; having When the detection unit detects an abnormality, the control unit at least performs either a notification to an outside or a storage while maintaining the permissible state, The detection unit is an abnormality detection device that detects an abnormality based on the first voltage and the second voltage when the control unit is controlling the relay to be in the cut-off state, on the condition that the fault detection device detects the normal state.

4. A control unit for controlling the relay, The abnormality detection device according to claim 1 , wherein the control unit maintains the interrupted state when the detection unit detects an abnormality.

5. A control unit for controlling the relay, The abnormality detection device according to claim 1 , wherein, when the detection unit detects an abnormality, the control unit at least either notifies an outside source or stores the abnormality while maintaining the permissible state.

6. An abnormality detection method for detecting an abnormality in a power supply system having a first power supply unit, a second power supply unit, a power path that is a path for transmitting power between the first power supply unit and the second power supply unit, and a relay that switches between an allowable state that allows current to flow through the power path and a cut-off state that cuts off current to the power path, the method comprising: a first operation by a control unit to switch the relay to the interrupted state; A second operation in which a first voltage detection unit detects a first voltage on a side of the first power supply unit in the power path relative to the relay, after at least the first operation; a third operation in which a second voltage detection unit detects a second voltage on a side of the second power supply unit than the relay in the power path after at least the first operation; a fourth operation in which a detection unit detects an abnormality based on the first voltage and the second voltage in the interrupted state after the second operation and the third operation are executed; Including, The control unit periodically alternately executes the first operation and an enabling operation of switching the relay to the enabling state.

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