On-vehicle device, determination method, and computer program

Abstract

To provide an on-vehicle device or the like capable of efficiently determining a failure state of an opening / closing device.SOLUTION: An on-vehicle device includes: an opening / closing device provided on a power line from a power supply device mounted on a vehicle; and a control unit for controlling output of electric power of the opening / closing device to a downstream side in a flow direction of electric current from the power supply device by applying voltage to the opening / closing device, where the control unit acquires a current value corresponding to the electric power output from the opening / closing device to the downstream side, and determines whether or not the opening / closing device is in a failure state based on an application state of the voltage to the opening / closing device, the current value acquired from the opening / closing device, and an input current value due to the electric power supplied from the power supply device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present technology relates to an in-vehicle device, a determination method, and a computer program. [Background technology]

[0002] A vehicle is equipped with a power supply control device (see, for example, Patent Document 1) that controls power supply from a battery to a load. In the power supply control device described in Patent Document 1, a semiconductor switch is provided in a current path of a current flowing from the battery to the load, and the power supply from the battery to the load is controlled by switching the semiconductor switch on or off.

[0003] The semiconductor switch has a control end. For example, when the semiconductor switch is a FET (Field Effect Transistor), the control end is a gate. The resistance value between both ends of the semiconductor switch changes according to the voltage at the control end. By adjusting the voltage at the control end, the resistance value between both ends of the semiconductor switch is adjusted to a sufficiently small value, and the semiconductor switch is switched on. By adjusting the voltage at the control end, the resistance value between both ends of the semiconductor switch is adjusted to a sufficiently large value, and the semiconductor switch is switched off. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-143905 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the power supply control device of Document 1, no consideration is given to efficiently determining the fault state of the switchgear.

[0006] The present disclosure has been made in consideration of the above circumstances, and has an object to provide an in-vehicle device or the like that can efficiently determine a fault state of a switching device. [Means for solving the problem]

[0007] An in-vehicle device according to one embodiment of the present disclosure includes an opening / closing device provided on a power line from a power supply device mounted on a vehicle, and a control unit that controls the output of power from the opening / closing device to the downstream side in the direction of current flow from the power supply device by applying a voltage to the opening / closing device, and the control unit acquires a current value corresponding to the power output from the opening / closing device to the downstream side, and determines whether or not the opening / closing device is in a fault state based on the state of voltage application to the opening / closing device, the current value acquired from the opening / closing device, and the input current value of the power supplied from the power supply device. Effect of the Invention

[0008] An in-vehicle device according to an embodiment of the present disclosure can efficiently determine a fault state of the opening and closing device. [Brief description of the drawings]

[0009] [Figure 1] 1 is a block diagram showing a configuration of a main part of a power supply system; [Diagram 2] FIG. 2 is a block diagram showing an example of the configuration of a microcomputer of an individual ECU. [Diagram 3] 2 is a block diagram showing an example of a connection between a microcomputer of an individual ECU and an IPD. [Figure 4] 4 is a flowchart showing a procedure of a failure determination process. [Diagram 5] FIG. 4 is an explanatory diagram illustrating an example of a failure determination table. [Figure 6] FIG. 11 is an explanatory diagram illustrating an example of a determination result table. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [Description of the embodiments of the present disclosure] First, the embodiments of the present disclosure will be listed and described. At least a part of the embodiments described below may be arbitrarily combined.

[0011] (1) An in-vehicle device according to one embodiment of the present disclosure includes a switching device provided on a power line from a power supply device mounted on a vehicle, and a control unit that controls the output of power from the switching device to a downstream side in the direction of current flow from the power supply device by applying a voltage to the switching device, and the control unit acquires a current value corresponding to the power output from the switching device to the downstream side, and determines whether or not the switching device is in a fault state based on the state of voltage application to the switching device, the current value acquired from the switching device, and the input current value of the power supplied from the power supply device.

[0012] In this embodiment, the switchgear is, for example, an IPD (Intelligent Power Device), and when a voltage is applied from the control unit, the switchgear outputs power supplied from an upstream power supply device to a load connected downstream. That is, the switchgear functions as a switch that switches the power output to the load based on the state of application of the voltage from the control unit. The switchgear and the control unit are connected via two control lines. One control line is a control line for the control unit to apply a voltage to the switchgear. The other control line is a control line for the control unit to obtain from the switchgear a current value corresponding to the power output from the switchgear to the downstream side. That is, a microcomputer (microcomputer) equipped with a control unit is connected to one switchgear via two pin terminals (PIN). The switchgear may be in a fault state including an open fault state in which the switchgear does not output power to the downstream side despite being applied with a high level voltage from the control unit, or a short fault state in which the switchgear outputs power to the downstream side despite being applied with a low level voltage that is lower than the high level voltage from the control unit. The control unit determines whether or not the switchgear is in a fault state based on the presence or absence of application of a voltage to the switchgear and the current value obtained from the switchgear. In addition, when the switching device is in a faulty state, the current value detection terminal for detecting the current value corresponding to the power output to the downstream side may also be damaged, and the current value acquired by the control unit from the switching device may not match the current value of the power actually output by the switching device to the downstream side. The control unit can determine whether the switching device is in a faulty state even when the current value detection terminal of the switching device is damaged, by determining whether the current value (input current value) of the power supplied to the in-vehicle device corresponds to the current value acquired from the switching device. Therefore, the control unit does not need to acquire the voltage value of the power output by the switching device to the downstream side in order to determine whether the switching device is faulty, and the control line for acquiring the voltage value is not connected to the pin terminal of the microcomputer including the control unit. This reduces the number of pin terminals used to connect to one switching device in the microcomputer including the control unit, making it possible to connect a large number of switching devices to the control unit.The control unit may obtain a voltage value converted from the current value transmitted by the switching device using a pull-down resistor, and determine whether or not the switching device is in a fault state based on the obtained voltage value.

[0013] (2) In one embodiment of the in-vehicle device of the present disclosure, the control unit acquires the input current value from an upstream device arranged upstream on the side of the power supply device, the opening / closing device and an upstream opening / closing device included in the upstream device are connected by the power line, and the input current value is a current value flowing through the power line.

[0014] In this embodiment, the control unit of the in-vehicle device acquires an input current value from an upstream device provided upstream of the in-vehicle device. The in-vehicle device according to this embodiment is, for example, an individual ECU (left zone ECU or right zone ECU), and the upstream device is, for example, an integrated ECU (front zone ECU). The upstream device has a control unit, and the control unit of the upstream device and the control unit of the in-vehicle device can communicate with each other, for example, via CAN or Ethernet. The control unit of the in-vehicle device acquires an input power value from the control unit of the upstream device, and can determine whether or not the opening / closing device of the in-vehicle device is in a faulty state based on the input current value acquired from the control unit of the upstream device.

[0015] (3) An in-vehicle device according to one embodiment of the present disclosure includes a plurality of the opening / closing devices, and the control unit determines that the opening / closing device is in a fault state when the input current value does not match the sum of the current values ​​obtained from each of the plurality of opening / closing devices.

[0016] In this aspect, the power supplied from the upstream device is distributed to multiple switching devices within the vehicle-mounted device and output from each switching device to a downstream load. When the switching device is not in a faulty state, the input current value matches the sum of the current values ​​acquired by the control unit of the vehicle-mounted device from each switching device. When the switching device is in a faulty state, the input current value may not match the sum of the current values ​​acquired by the control unit of the vehicle-mounted device from each switching device. The control unit of the vehicle-mounted device can determine whether the switching device is in a faulty state by determining whether the input current value matches the sum of the current values ​​acquired by the control unit of the vehicle-mounted device from each switching device.

[0017] (4) In one embodiment of the in-vehicle device according to the present disclosure, when no voltage is applied to the opening / closing device, the control unit determines whether the input current value matches the sum of the current values ​​acquired from each of the multiple opening / closing devices when the current value acquired from the opening / closing device is less than a predetermined threshold, and if they do not match, determines that the opening / closing device is in a short-circuit fault state.

[0018] In this embodiment, the current value detection terminal may be stuck at Lo, where the current value detection terminal continues to detect a current value less than a predetermined threshold value even though the switching device is outputting power to the downstream side. When the control unit of the in-vehicle device is not applying a voltage to the switching device, if the current value acquired by the control unit from the switching device is less than a predetermined threshold value, there are two possible cases: the switching device is in a normal state, and the switching device is in a short-circuit fault state and the current value detection terminal is stuck at Lo. In this case, the control unit of the in-vehicle device can determine whether the switching device is in a short-circuit fault state by determining whether the input current value matches the sum of the current values ​​acquired from each switching device. The state in which the control unit of the in-vehicle device is not applying a voltage to the switching device includes a state in which the control unit of the in-vehicle device is applying a low-level voltage to the switching device.

[0019] (5) In an in-vehicle device according to one embodiment of the present disclosure, when a voltage is applied to the opening / closing device, the control unit determines whether the input current value matches the sum of the current values ​​acquired from each of the multiple opening / closing devices when the current value acquired from the opening / closing device is equal to or greater than a predetermined threshold, and if they do not match, determines that the opening / closing device is in an open fault state.

[0020] In this embodiment, the current value detection terminal may be in a Hi-fixed state where it continues to detect a current value equal to or greater than a predetermined threshold even though the switching device is not outputting power to the downstream side. When the control unit of the in-vehicle device applies a voltage to the switching device, if the current value acquired by the control unit from the switching device is equal to or greater than a predetermined threshold, two cases are considered: the switching device is in a normal state, and the switching device is in an open-fault state and the current value detection terminal is in a Hi-fixed state. In this case, the control unit of the in-vehicle device can determine whether the switching device is in an open-fault state by determining whether the current value of the power supplied to the in-vehicle device matches the sum of the current values ​​acquired from each switching device. Note that the state in which the control unit of the in-vehicle device applies a voltage to the switching device includes a state in which the control unit of the in-vehicle device applies a high-level voltage to the switching device.

[0021] (6) A determination method according to one embodiment of the present disclosure obtains a current value corresponding to the power output downstream from a switching device installed on a power line from a power supply device mounted on a vehicle, and determines whether or not the switching device is in a fault state based on the voltage application state to the switching device, the current value obtained from the switching device, and the input current value of the power supplied from the power supply device.

[0022] In this aspect, by determining whether the current value (input current value) of the power supplied to the in-vehicle device corresponds to the current value acquired from the switching device, it is possible to determine whether the switching device is in a faulty state even if the current value detection terminal of the switching device is damaged. Therefore, the control unit does not need to acquire the voltage value of the power output by the switching device to the downstream side in order to determine whether the switching device is faulty, and the control line for acquiring the voltage value is not connected to the pin terminal of the microcomputer that includes the control unit. This reduces the number of pin terminals used to connect to one switching device in the microcomputer that includes the control unit, making it possible to connect a large number of switching devices to the control unit.

[0023] (7) A program according to one embodiment of the present disclosure acquires a current value corresponding to the power output downstream from a switching device installed on a power line from a power supply device mounted on a vehicle, and causes a computer to execute a process of determining whether the switching device is in a fault state based on the voltage application state to the switching device, the current value acquired from the switching device, and the input current value of the power supplied from the power supply device.

[0024] In this aspect, by determining whether the current value (input current value) of the power supplied to the in-vehicle device corresponds to the current value acquired from the switching device, it is possible to determine whether the switching device is in a faulty state even if the current value detection terminal of the switching device is damaged. Therefore, the control unit does not need to acquire the voltage value of the power output by the switching device to the downstream side in order to determine whether the switching device is faulty, and the control line for acquiring the voltage value is not connected to the pin terminal of the microcomputer that includes the control unit. This reduces the number of pin terminals used to connect to one switching device in the microcomputer that includes the control unit, making it possible to connect a large number of switching devices to the control unit.

[0025] [Details of the embodiment of the present disclosure] Specific examples of power supply control devices according to embodiments of the present disclosure will be described below with reference to the drawings. Note that the present invention is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.

[0026] (Embodiment) FIG. 1 is a block diagram showing the main configuration of a power supply system S. In FIG. 1, power lines are indicated by solid lines, and control lines are indicated by dashed lines. Communication lines are indicated by thick lines. The power supply system S is mounted on a vehicle M, and includes a power supply device 1, an integrated ECU (Electronic Control Unit) 2, an individual ECU 3, and a plurality of loads 4. The power supply device 1 is a power supply that outputs a direct current. The integrated ECU 2 corresponds to an upstream device, and is connected to a positive electrode of the power supply device 1 and the individual ECU 3. The individual ECU 3 corresponds to an in-vehicle device, and is connected to the integrated ECU 2 and one end of the plurality of loads 4. The negative electrode of the power supply device 1 and the other end of the load 4 are grounded. The integrated ECU 2 may be a front zone ECU mounted in a front zone of the vehicle M, and the individual ECU 3 may be a left zone ECU mounted in a left zone of the vehicle M or a right zone ECU mounted in a right zone. In the following description, in the current path from the power supply device 1 to the load 4, the power supply device 1 side is referred to as the upstream side of the current, and the load 4 side is referred to as the downstream side of the current.

[0027] The integrated ECU 2 includes a microcomputer 21 and an IPD (Intelligent Power Device) 22. The power supplied from the power supply device 1 is output to the downstream side via the IPD 22 of the integrated ECU 2. The IPD 22 corresponds to an upstream opening and closing device. The microcomputer 21 controls the output of power to the downstream side of the IPD 22, and acquires the current value of the power output by the IPD 22 to the downstream side. The power output to the downstream side via the IPD 22 is supplied to the individual ECU 3.

[0028] The individual ECU 3 includes a microcomputer 31 and a plurality of IPDs 32. Power supplied from the power supply device 1 to the individual ECU 3 via the IPD 22 of the integrated ECU 2 is distributed to the plurality of IPDs 32 and output to a downstream load 4 via each IPD 32. The IPD 32 corresponds to a switching device. The microcomputer 31 controls the output of power to the downstream side of the IPD 32, and obtains a current value corresponding to the power output by the IPD 32 to the downstream side.

[0029] The microcomputer 21 of the integrated ECU 2 and the microcomputer 31 of the individual ECU 3 are connected by a communication bus B, and can communicate with each other using a communication protocol such as CAN (Control Area Network), CAN-FD, or Ethernet (registered trademark). The microcomputer 21 of the integrated ECU 2 transmits to the microcomputer 31 of the individual ECU 3 a current value of the power output by the IPD 22 to the downstream side, that is, a current value (input current value) of the power supplied to the individual ECU 3. The IPD 22 (upstream switching device) and the IPD 32 (switching device) may be provided in one ECU. In this case, the IPD 22 (upstream switching device) and the IPD 32 (switching device) may be controlled by the same microcomputer. The microcomputer 31 of the individual ECU 3 may control the output of power to the downstream side of the IPD 22 of the integrated ECU 2, and may also obtain a current value of the power output by the IPD 22 to the downstream side.

[0030] 2 is a block diagram showing an example of the configuration of the microcomputer 31 of the individual ECU 3. The microcomputer 31 has a control unit 311, a storage unit 312, an input / output I / F 313, and an in-vehicle communication unit 314. These are connected to an internal bus 315.

[0031] The control unit 311 has a processing element that executes processing, for example, a CPU (Central Processing Unit), and functions as a processing unit. The processing element of the control unit 311 reads and executes a computer program P stored in the storage unit 312, thereby executing a process of controlling the output of power to the downstream side of each IPD 32, a process of determining a failure of each IPD 32, and a process of recording a failure determination result of each IPD 32. Note that the processes executed by the control unit 311 may be executed by an external device connected to the individual ECU 3 wirelessly or by wire.

[0032] The storage unit 312 is a non-volatile memory. The storage unit 312 stores a computer program P, a fault judgment table T1, and a judgment result table T2. The fault judgment table T1 and the judgment result table T2 will be described later in detail. The computer program P may be provided to the microcomputer 31 using a non-transient storage medium A on which the computer program P is readably recorded. The storage medium A is, for example, a portable memory. When the storage medium A is a portable memory, the processing element of the control unit 311 may read the computer program P from the storage medium A using a reading device (not shown). The read computer program P is stored in the storage unit 312. Furthermore, the computer program P may be provided to the microcomputer 31 by a communication unit (not shown) of the microcomputer 31 communicating with an external device. The storage unit 312 also stores threshold values ​​and coefficients, which will be described later. The threshold values ​​and coefficients stored in the storage unit 312 may be changed by reprogramming, for example, depending on the load 4 connected to the individual ECU 3 or the type of the IPD 32 provided in the individual ECU 3. Furthermore, the thresholds and coefficients stored in the storage unit 312 may be updated through communication with an external device.

[0033] The input / output I / F 313 is connected to the multiple IPDs 32 via control lines. The input / output I / F 313 switches the voltage applied (output) to the IPDs 32 between a high-level voltage or a low-level voltage in accordance with an instruction from the control unit 311. A voltage value corresponding to a current value output by the IPDs 32 is input to the input / output I / F 313. The control unit 311 acquires the voltage value input to the input / output I / F 313.

[0034] The in-vehicle communication unit 314 is an input / output interface using a communication protocol such as CAN, CAN-FD, or Ethernet (registered trademark), and the control unit 311 communicates with the integrated ECU 2 or other in-vehicle devices via the in-vehicle communication unit 314. The in-vehicle communication unit 314 acquires, from the microcomputer 21 of the integrated ECU 2, the electric power output by the IPD 22 of the integrated ECU 2 to the downstream side, i.e., the current value (input current value) of the electric power supplied to the individual ECU 3.

[0035] Fig. 3 is a block diagram showing an example of connection between the microcomputer 31 and the IPD 32 of the individual ECU 3. Fig. 3 shows an example of connection between one IPD 32 and the microcomputer 31, and omits illustration of the other IPDs 32. The input / output I / F 313 of the microcomputer 31 has a plurality of pin terminals (PIN(1), PIN(2), . . . PIN(n)).

[0036] The IPD 32 includes a power receiving terminal 321, a power output terminal 322, a voltage application terminal 323, and a current value detection terminal 324. A power line that connects the IPD 22 of the integrated ECU 2 and the IPD 32 of the individual ECU 3 is connected to the power receiving terminal 321, and the power receiving terminal 321 receives power supplied from the upstream side.

[0037] The power output terminal 322 is connected to a power line that connects the IPD 32 and the load 4, and outputs the power received by the power receiving terminal 321 to the downstream load 4.

[0038] The voltage application terminal 323 is connected to the input / output I / F 313 of the microcomputer 31 via a control line. In this embodiment, the voltage application terminal 323 is connected to PIN(1) of the input / output I / F 313. The power output from the power output terminal 322 is controlled based on the state of the voltage applied from the microcomputer 31 to the voltage application terminal 323. Specifically, the IPD 32 includes, for example, an N-channel type FET (Field Effect Transistor). The drain of the FET is connected to the power receiving terminal 321, and the source is the power output terminal 322. The gate of the FET is connected to the voltage application terminal 323, and the voltage applied to the voltage application terminal 323 is applied to the gate of the FET. As a result, when a high-level voltage is applied to the voltage application terminal 323, the power received by the power receiving terminal 321 (power supplied to the IPD 32) is output from the power output terminal 322 to the downstream load 4 via the FET. When a low-level voltage is applied to the voltage application terminal 323, no power is output from the power output terminal 322 to the downstream load 4. The switching device (IPD 32) may be configured by a P-channel type FET or a mechanical relay, etc.

[0039] The current value detection terminal 324 is connected to the input / output I / F 313 of the microcomputer 31 via a control line. In this embodiment, the current value detection terminal 324 is connected to PIN(2) of the input / output I / F 313. The current value detection terminal 324 outputs a current value corresponding to the power output from the power output terminal 322 to the microcomputer 31. Specifically, the IPD 32 includes, for example, a current detection circuit. The current detection circuit is connected between the source of the FET and the power output terminal 322. The current value detection terminal 324 is also connected to the current detection circuit, and outputs a current value obtained by multiplying the current value of the power output from the power output terminal 322 detected by the current detection circuit by a predetermined coefficient to the microcomputer 31. A pull-down resistor R is connected between the power output terminal 322 and the microcomputer 31. This allows the microcomputer 31 to obtain a voltage value proportional to the current value output from the current value detection terminal 324. That is, the microcomputer 31 can obtain a voltage value that is proportional to the current value of the power output from the power output terminal 322 of the IPD 32 (output current value).

[0040] As described above, each of the other IPDs 32 included in the individual ECU 3 also includes the power receiving terminal 321, the power output terminal 322, the voltage application terminal 323, and the current value detection terminal 324. In addition, each of the IPDs 32 is connected to two pin terminals (PIN) in the microcomputer 31.

[0041] 4 is a flowchart showing the procedure of the failure determination process. The control unit 311 of the individual ECU 3 acquires the state of voltage application to the IPD 32 (S1). The control unit 311 acquires the current value (output current value) of the power output from the power output terminal 322 of the IPD 32 from the IPD 32 that is the failure determination target (S2). The control unit 311 also acquires the output current value of the other IPD 32 that is not the failure determination target (S3). Note that the control unit 311 acquires the output current value of the IPD 32 by performing a calculation based on the voltage value acquired at the pin terminal connected to the current value detection terminal of the IPD 32 in S2 and S3. The control unit 311 acquires the input current value for the individual ECU 3 from the microcomputer 21 of the integrated ECU 2 (S4).

[0042] The control unit 311 of the microcomputer 31 determines whether or not the voltage applied to the IPD 32 that is the failure determination target is a high-level voltage (S5). If the voltage applied to the IPD 32 is a high-level voltage (S5: YES), the control unit 311 determines whether or not the output current value of the IPD 32 that is the failure determination target is equal to or greater than a predetermined threshold (S6). The threshold in S6 is a current value of a cutoff characteristic that has a minimum current value among cutoff characteristics for a load that is assumed to be connected to the IPD 32. The control unit 311 may determine whether or not there is an output current from the IPD 32, that is, whether the output current value is a value higher than 0 A or 0 A. If the output current value of the IPD 32 that is the failure determination target is equal to or greater than the predetermined threshold (S6: YES), the control unit 311 determines whether or not the input current value to the IPD 32 matches the total of the output current values ​​of all the IPDs 32 included in the individual ECU 3 (S7). If the sum of the input current value and the output current value matches (S7: YES), the control unit 311 determines that the IPD 32 that is the target of failure judgment is in a normal state (S8). If the output current value of the IPD 32 that is the target of failure judgment is not equal to or greater than a predetermined threshold (is less than the threshold) (S6: NO), or if the sum of the input current value and the output current value does not match (S7: NO), the control unit 311 determines that the IPD 32 that is the target of failure judgment is in an open failure state (S9). Note that, if it is determined that the IPD 32 is in an open failure state, the control unit 311 may, for example, stop control of the IPD 32 that is determined to be in an open failure state.

[0043] When the voltage applied to the IPD 32 is not a high-level voltage (is a low-level voltage) (S5: NO), the control unit 311 judges whether or not the output current value of the IPD 32 that is the failure judgment target is equal to or greater than a predetermined threshold (S10). The threshold in S10 is a current value of a cutoff characteristic with a minimum current value among cutoff characteristics for a load assumed to be connected to the IPD 32. The control unit 311 may judge whether or not there is an output current of the IPD 32, that is, whether the output current value is a value higher than 0 A or 0 A. When the output current value of the IPD 32 that is the failure judgment target is not equal to or greater than a predetermined threshold (is less than the threshold) (S10: NO), the control unit 311 judges whether or not the input current value to the IPD 32 matches the total of the output current values ​​of all the IPDs 32 provided in the individual ECU 3 (S11). When the input current value matches the total of the output current value (S11: YES), the control unit 311 judges that the IPD 32 that is the failure judgment target is in a normal state (S12). If the output current value of the IPD 32 that is the failure judgment target is equal to or greater than a predetermined threshold value (S10: YES), or if the sum of the input current value and the output current value does not match (S11: NO), the control unit 311 judges that the IPD 32 that is the failure judgment target is in a short-circuit fault state (S13). Note that, if it is determined that the IPD 32 is in a short-circuit fault state, the control unit 311 may, for example, transmit a signal to the microcomputer 21 of the integrated ECU 2 to request the stop of power supply to the individual ECUs 3.

[0044] After determining the state of the IPD 32 in S8, S9, S12, or S13, the control unit 311 stores (stores) the determination result in a determination result table (S14), and ends the process.

[0045] 5 is an explanatory diagram showing an example of the failure determination table T1. The control unit 311 of the individual ECU 3 may determine the state of the IPD 32 by referring to the failure determination table T1. The management items (fields) of the failure determination table T1 include, for example, a condition field including a voltage application field, an output current value field, and an input current value field, and a state field including an IPD state field, and a current value detection terminal state field.

[0046] Each field of the condition field stores a condition for determining the state of the IPD 32. The voltage application field stores the state of voltage application from the microcomputer 31 to the IPD 32. When a low-level voltage is applied to the IPD 32, "L" is stored in the voltage application field. When a high-level voltage is applied to the IPD 32, "H" is stored in the voltage application field.

[0047] The output current value field stores the condition for the threshold of the output current value of IPD 32 acquired by control unit 311. When the condition indicates that the output current value is less than the threshold, "L" is stored in the output current value field. When the condition indicates that the output current value is equal to or greater than the threshold, "H" is stored in the output current value field.

[0048] The input current value field stores a condition as to whether or not the input current value acquired by the control unit 311 from the microcomputer 21 of the integrated ECU 2 matches the sum of the output current values ​​of all the IPDs 32 provided in the individual ECU 3. When a condition is indicated in which the input current value and the sum of the output current values ​​match, "match" is stored in the input current value field. When a condition is indicated in which the input current value and the sum of the output current values ​​do not match, "mismatch" is stored in the input current value field. Note that when it does not matter whether the input current value and the output current value match, a null value is stored in the input current value field.

[0049] Each field of the status field stores the status of the IPD 32 or the current value detection terminal determined by the control unit 311 for the condition stored in the condition field. The IPD status field stores the status of the IPD 32 determined by the control unit 311 for the condition. The current value detection terminal status field stores the status of the current value detection terminal of the IPD 32 determined by the control unit 311 for the condition.

[0050] When a low-level voltage is applied to the IPD 32, if the output current value is less than the threshold and the sum of the input current value and the output current value match, the IPD 32 and the current value detection terminal 324 are determined to be in a normal state. When a low-level voltage is applied to the IPD 32, if the output current value is equal to or greater than the threshold, the IPD 32 is determined to be in a short-circuit fault state, and the current value detection terminal 324 is determined to be in a normal state or a Hi-fixed state. When a low-level voltage is applied to the IPD 32, if the output current value is less than the threshold and the sum of the input current value and the output current value do not match, the IPD 32 is determined to be in a short-circuit fault state, and the current value detection terminal 324 is determined to be in a Lo-fixed state.

[0051] When a high-level voltage is applied to the IPD 32, if the output current value is equal to or greater than the threshold value and the sum of the input current value and the output current value matches, the IPD 32 and the current value detection terminal 324 are determined to be in a normal state. When a high-level voltage is applied to the IPD 32, if the output current value is less than the threshold value, the IPD 32 is determined to be in an open fault state, and the current value detection terminal 324 is determined to be in a normal state or a L fixed state. When a high-level voltage is applied to the IPD 32, if the output current value is equal to or greater than the threshold value and the sum of the input current value and the output current value does not match, the IPD 32 is determined to be in an open fault state, and the current value detection terminal 324 is determined to be in a Hi fixed state.

[0052] 6 is an explanatory diagram showing an example of the judgment result table T2. In the judgment result table T2, the time when the control unit 311 performed the judgment, information for identifying the IPD 32 whose state was judged, and the judgment result are stored in association with each other. The management items of the judgment result table include, for example, a judgment time field, a judgment IPD field, and a judgment result field.

[0053] The determination time field stores the time when the control unit 311 of the microcomputer 31 determined the state of the IPD 32, with the time when the vehicle M starts and the microcomputer 31 starts controlling each IPD 32 as a reference (time 0). The control unit 311 determines the states of the multiple IPDs 32 included in the individual ECU 3 in a cycle of, for example, 5 milliseconds. The cycle in which the control unit 311 performs the determination is not limited to 5 milliseconds, and may be, for example, 10 milliseconds.

[0054] The determination IPD field stores information for identifying the IPD 32 whose state has been determined (which has been subject to failure determination). In this embodiment, the multiple IPDs 32 provided in the individual ECU 3 are assigned codes (IPD32(a), IPD32(b), IPD32(c), etc.) for identifying each IPD 32. The determination IPD field stores the code of the IPD 32 whose state has been determined. After determining the states of all the IPDs 32, the control unit 311 repeatedly determines the states of all the IPDs 32 again, starting with IPD32(a). The control unit 311 outputs the determination results of each IPD 32 in turn at a predetermined cycle, and stores the output determination result in a new record in the determination result table T2 each time.

[0055] The determination result field stores the result of the determination of the state of the IPD 32 by the control unit 311 (either "normal", "short circuit failure", or "open circuit failure"). Note that the determination result table T2 may include a current detection terminal state determination result field, in which the state of the current detection terminal 324 of the IPD 32 determined by the control unit 311 is stored.

[0056] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The technical features described in each embodiment can be combined with each other, and the scope of the present invention is intended to include all modifications within the scope of the claims and equivalents to the scope of the claims. In addition, the independent claims and dependent claims described in the claims can be combined with each other in all combinations regardless of the reference format. Furthermore, the claims use a format in which a claim references two or more other claims (multiple claim format), but this is not limited to this. A format in which a multiple claim (multi-multi claim) that references at least one multiple claim may be used. [Explanation of symbols]

[0057] 1 Power supply 2 Integrated ECU 21 Microcomputer 22 IPD 3 Individual ECU 31 Microcomputer 311 Control Unit 312 Storage section 313 Input / Output Interface 314 In-vehicle communication unit 32 IPD 321 Power receiving terminal 322 Power output terminal 323 Voltage application terminal 324 Current detection terminal 4. Load A storage medium M Vehicle P Computer Program S Power Supply System T1 Fault Judgment Table T2 Judgment result table

Claims

1. A switching device provided on a power line extending from a power supply device mounted on a vehicle; a control unit that applies a voltage to the switchgear to control an output of electric power from the switchgear to a downstream side in a current flow direction from the power supply device; Equipped with The control unit is Acquire a current value corresponding to the power output from the switching device to the downstream side; Whether or not the switching device is in a fault state is determined based on a state of voltage application to the switching device, a current value acquired from the switching device, and an input current value based on the power supplied from the power supply device. In-vehicle device.

2. The control unit acquires the input current value from an upstream device that is disposed on the upstream side of the power supply device, the switchgear and an upstream switchgear included in the upstream device are connected by the power line, The input current value is a value of a current flowing through the power line. The in-vehicle device according to claim 1 .

3. A plurality of the opening and closing devices are provided, The control unit is When the input current value does not match the sum of the current values ​​acquired from each of the plurality of switching devices, it is determined that the switching device is in a fault state. The in-vehicle device according to claim 1 .

4. The control unit is When no voltage is applied to the switching device, if the current value acquired from the switching device is less than a predetermined threshold value, determining whether or not the input current value matches a sum of current values ​​acquired from each of the multiple switching devices; If they do not match, it is determined that the switchgear is in a short circuit fault state. The vehicle-mounted device according to claim 3.

5. The control unit is determining whether or not the input current value matches a sum of current values ​​acquired from each of the plurality of switching devices when a voltage is applied to the switching device and the current value acquired from the switching device is equal to or greater than a predetermined threshold value; If there is no match, it is determined that the switchgear is in an open fault state. The vehicle-mounted device according to claim 3.

6. A current value corresponding to power output downstream from a switching device provided on a power line extending from a power supply device mounted on a vehicle is obtained; Whether or not the switching device is in a fault state is determined based on a state of voltage application to the switching device, a current value acquired from the switching device, and an input current value based on the power supplied from the power supply device. Judgment method.

7. A current value corresponding to power output downstream from a switching device provided on a power line extending from a power supply device mounted on a vehicle is obtained; Whether or not the switching device is in a fault state is determined based on a state of voltage application to the switching device, a current value acquired from the switching device, and an input current value based on the power supplied from the power supply device. A computer program that causes a computer to carry out processing.

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