In-vehicle control device

Abstract

A control device (1) for a vehicle has a control section (21) that switches a cutoff section (14) from an allowable state to a cutoff state when a cutoff condition is satisfied, and a setting section (22) that sets the cutoff condition. The setting section (22) sets the cutoff condition based on which one of a first operation and a second operation is being performed, the first operation exchanging electric power between an electric power storage section (90) and a first exchange section (a connection section (91)) when a first switch (11) is in an on state, and the second operation exchanging electric power between the electric power storage section (90) and a second exchange section (a first load (92)) when a second switch (12) is in an on state.

Description

Technical Field

[0001] This disclosure relates to vehicle-mounted control devices. Background Technology

[0002] Patent Document 1 discloses a power supply device mounted on a vehicle. This power supply device includes a battery, an electrical load, and a fuse. The fuse is positioned between the battery and the electrical load and functions as an overcurrent protection element.

[0003] Patent document 2 discloses an overcurrent protection device installed between a power supply and a load circuit. The load circuit has an electrical load and wires that are electrically connected to each other. The overcurrent protection device estimates the thermal characteristics of the wires based on the load current, and cuts off the switching element based on the estimated thermal characteristics and the load current.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-67977

[0007] Patent Document 2: Japanese Patent Application Publication No. 2019-97357 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, in structures with multiple switching units that exchange power with the energy storage unit, it is sometimes desirable to switch the cutting-off conditions based on which switching unit the energy storage unit is exchanging power with. However, if the technology of Patent Document 1 or Patent Document 2 is used to set a cutting-off unit for each path corresponding to each switching unit, it leads to an increase in the number of components.

[0010] Therefore, the purpose of this disclosure is to provide a technique that can suppress the increase in the number of components and properly perform overcurrent protection in a structure having multiple switching units that exchange power with the energy storage unit.

[0011] Technical solutions for solving the problem

[0012] The vehicle-mounted control device disclosed herein is used in a vehicle-mounted system, the vehicle-mounted system comprising: a power storage unit; a plurality of switching units for exchanging power with the power storage unit; a common path disposed between the power storage unit and the plurality of switching units; a first branch line disposed between a first switching unit of the plurality of switching units and the common path, and electrically connected to the common path; a second branch line disposed between a second switching unit of the plurality of switching units and the common path, and electrically connected to the common path; a first switch disposed on the first branch line; a second switch disposed on the second branch line; and a cut-off unit for switching from an allowed state that allows current flow in the common path to a cut-off state that cuts off current flow in the common path, wherein...

[0013] The vehicle-mounted control device includes: a control unit that, when a cut-off condition is met, switches the cut-off unit from the permitted state to the cut-off state; and

[0014] The setting unit sets the cutting conditions.

[0015] The setting unit sets the cutting-off condition based on which of the first and second actions is being performed. The first action is to exchange power between the energy storage unit and the first exchange unit when the first switch is on, and the second action is to exchange power between the energy storage unit and the second exchange unit when the second switch is on.

[0016] Invention Effects

[0017] According to this disclosure, in a structure having multiple switching units that exchange power with the energy storage unit, overcurrent protection can be appropriately performed while suppressing an increase in the number of components. Attached Figure Description

[0018] Figure 1 This is a circuit diagram that roughly illustrates the structure of the vehicle-mounted system according to the first embodiment.

[0019] Figure 2 It is a graph showing the relationship between the first cutting-off characteristic and the first switch cutting-off characteristic.

[0020] Figure 3 It is a graph showing the relationship between the second cutting-off characteristic and the second switch cutting-off characteristic.

[0021] Figure 4 It is a graph showing the relationship between the third cut-off characteristic and the third switch cut-off characteristic.

[0022] Figure 5 This is a flowchart illustrating the control process executed by the vehicle-mounted control device according to the first embodiment.

[0023] Figure 6 This is a circuit diagram that roughly illustrates the structure of the vehicle-mounted system according to the second embodiment.

[0024] Figure 7 This is a flowchart illustrating the control process executed by the vehicle-mounted control device according to the second embodiment. Detailed Implementation

[0025] [Description of embodiments of this disclosure]

[0026] The following are examples of embodiments of this disclosure.

[0027] [1] A vehicle-mounted control device for use in a vehicle-mounted system, the vehicle-mounted system comprising: a power storage unit; a plurality of switching units for exchanging power with the power storage unit; a common path disposed between the power storage unit and the plurality of switching units; a first branch line disposed between a first switching unit of the plurality of switching units and the common path, and electrically connected to the common path; a second branch line disposed between a second switching unit of the plurality of switching units and the common path, and electrically connected to the common path; a first switch disposed on the first branch line; a second switch disposed on the second branch line; and a cut-off unit for switching from an allowable state that allows the flow of current in the common path to a cut-off state that cuts off the flow of current in the common path, wherein...

[0028] The vehicle-mounted control device has the following features:

[0029] The control unit, when the cutting-off condition is met, switches the cutting-off unit from the permitted state to the cutting-off state; and

[0030] The setting unit sets the cutting conditions.

[0031] The setting unit sets the cutting-off condition based on which of the first and second actions is being performed. The first action is to exchange power between the energy storage unit and the first exchange unit when the first switch is on, and the second action is to exchange power between the energy storage unit and the second exchange unit when the second switch is on.

[0032] The aforementioned vehicle-mounted control device switches the cutting-off section to the cutting-off state when the cutting-off condition is met, thereby cutting off the current flow in the common path between the energy storage unit and multiple exchange units. Furthermore, the vehicle-mounted control device can set the cutting-off condition based on which of the first and second actions is being performed. That is, without providing a cutting-off section corresponding to each exchange unit, the cutting-off condition can be switched according to which exchange unit the energy storage unit is exchanging power with. Therefore, in a structure with multiple exchange units exchanging power with the energy storage unit, overcurrent protection can be appropriately performed while suppressing an increase in the number of components.

[0033] [2] In the vehicle control device described in [1], the setting unit determines which of the first action and the second action is being performed based on whether the first switch and the second switch are in an on state or an off state.

[0034] Based on this structure, it is possible to simplify the determination of which action is being executed in the first and second actions.

[0035] [3] In the vehicle-mounted control device described in [1] or [2], the setting unit sets a first cutting-off condition included in the cutting-off condition when it determines that the first action is being performed, and sets a second cutting-off condition included in the cutting-off condition when it determines that the second action is being performed.

[0036] The first disconnection condition is that when the current flowing through the first branch line exceeds a first threshold current, the disconnection section is switched to the disconnection state before the first switch is switched to the open state.

[0037] The second disconnection condition is that when the current value flowing through the second branch line exceeds a second threshold current that is different from the first threshold current, the disconnection part is switched to the disconnection state before the second switch is switched to the open state.

[0038] According to this structure, when the current flowing through the first branch line exceeds a first threshold current during the first operation, the cutting-off section can be switched to the cutting-off state before the first switch. Furthermore, when the second operation is being performed, when the current flowing through the second branch line exceeds a second threshold current, the cutting-off section can be switched to the cutting-off state before the second switch.

[0039] [4] In the vehicle-mounted control device described in [3], the first switch is switched to the open state based on the first switch's disconnection characteristic.

[0040] The second switch is switched to the open state based on its disconnection characteristic.

[0041] The determination of whether the first cutting condition is met is based on the first cutting characteristic.

[0042] The determination of whether the second cutting condition is met is based on the second cutting characteristic.

[0043] The first switch-off characteristic, the second switch-off characteristic, the first switch-off characteristic, and the second switch-off characteristic are respectively defined by correspondence data representing the relationship between energizing time and current value.

[0044] In the energizing time of the first cut-off characteristic, the time corresponding to current values ​​below the first threshold current is longer than that of the first switch cut-off characteristic, and the time corresponding to current values ​​exceeding the first threshold current is shorter than that of the first switch cut-off characteristic.

[0045] In the energizing time of the second cut-off characteristic, the time corresponding to the current value below the second threshold current is longer than that of the second switch cut-off characteristic, and the time corresponding to the current value above the second threshold current is shorter than that of the second switch cut-off characteristic.

[0046] According to this structure, when the first operation is being performed and the current value flowing through the common path exceeds a first threshold current, the cutting-off section can be switched to the cutting-off state before the first switch based on the energizing time. Furthermore, when the second operation is being performed and the current value flowing through the common path exceeds a second threshold current, the cutting-off section can be switched to the cutting-off state before the second switch based on the energizing time.

[0047] [5] In any of [1] to [4], the first switching unit is a connection unit that is connected to an external power source via a charging cable.

[0048] The second switching unit is the load.

[0049] The shared path is both the discharge path from the energy storage unit and the charging path to the energy storage unit.

[0050] The first branch line is the path that directs the power supplied via the connection to the common path.

[0051] The second branch line is the path that directs power from the shared path to the load.

[0052] The setting unit sets the cut-off condition based on which of the charging and discharging actions is being performed. The charging action, when the first switch is on, causes the charging current supplied via the connection unit to flow to the energy storage unit. The discharging action, when the second switch is on, causes the discharging current to flow from the energy storage unit to the load.

[0053] Based on this structure, overcurrent protection can be appropriately implemented based on whether a charging or discharging operation is in progress.

[0054] [6] In the vehicle control device described in [5], the second threshold current is greater than the first threshold current.

[0055] According to this structure, a discharge operation with a large current flow is also allowed, compared to the charging operation.

[0056] [7] In the vehicle-mounted control device described in [6], the vehicle-mounted system includes: a third branch line disposed between the third switching unit of the plurality of switching units and the common path, and electrically connected to the common path; and a third switch disposed on the third branch line.

[0057] The third switching unit is the second load.

[0058] When the third switch is in the ON state, a second discharge operation is performed to allow the discharge current to flow from the energy storage unit to the second load.

[0059] When the setting unit determines that the second discharge operation is being performed, it sets a third cutoff condition included in the cutoff condition.

[0060] The third disconnection condition is the condition that the disconnection section is switched to the disconnection state before the third switch is switched to the open state when the current value flowing through the third branch line exceeds the third threshold current.

[0061] The third threshold current is different from the second threshold current.

[0062] According to this structure, the cutting condition of the cutting section can be different not only depending on whether the charging action or the discharging action is being performed, but also depending on whether the discharging action or the second discharging action is being performed.

[0063] [8] In the vehicle control device described in [6] or [7], the setting unit outputs an abnormal signal when it determines that both the charging operation and the discharging operation are being performed.

[0064] According to this structure, in a structure that does not assume that charging and discharging actions will occur in parallel, it is possible to notify the outside world of an anomaly that both charging and discharging actions are in progress.

[0065] [9] In any of [1] to [8], the vehicle control device includes: a specific load, which is different from the switching unit and receives power from the energy storage unit; and a specific branch line disposed between the specific load and the common path and electrically connected to the common path.

[0066] The vehicle-mounted control device also includes a temperature fuse, which is installed on the specific branch line and melts when the melting temperature is exceeded.

[0067] Based on this structure, in the event of a specific load grounding fault, it is easy to prevent the impact from spreading to the energy storage section and the switching section.

[0068] <First Implementation>

[0069] Figure 1 The vehicle system 100 shown is a system mounted on a vehicle 101, and includes an energy storage unit 90, a connection unit 91, a first load 92, a second load 93, an external ECU 94, a common path 80, a first branch line 81, a second branch line 82, a third branch line 83, and a vehicle control device 1.

[0070] The battery section 90 refers to batteries such as lithium-ion batteries.

[0071] The connection portion 91 corresponds to an example of the first exchange portion. The connection portion 91 is, for example, a charging inlet, exposed to the outside of the vehicle 101 through a cover that opens the DC charging port. A charging plug 111 is connected to the connection portion 91. Thus, the connection portion 91 is connected to an external power source 110 via a charging cable 112, and power is supplied from the external power source 110. The connection portion 91 can supply power from the external power source 110 to the energy storage unit 90 via the first branch line 81 and the common path 80.

[0072] The first load 92 corresponds to an example of the second switching unit. The first load 92 is, for example, an electric motor. The electric motor is, for example, a driving motor used in the case where vehicle 101 is an electric vehicle or a hybrid vehicle. The first load 92 receives power from the energy storage unit 90 via the common path 80 and the second branch line 82.

[0073] The second load 93 is an example of the third switching unit. The second load 93 is, for example, a high-voltage auxiliary unit, more specifically, an air conditioner, a heater, etc. The second load 93 receives power from the energy storage unit 90 via the common path 80 and the third branch line 83.

[0074] A common path 80 is provided between the energy storage unit 90 and multiple switching units (in this embodiment, a connection unit 91, a first load 92, and a second load 93). The common path 80 is a discharge path from the energy storage unit 90 and a charging path to the energy storage unit 90. The common path 80 is electrically connected to the energy storage unit 90.

[0075] The first branch line 81 is disposed between the energy storage unit 90 and the connecting unit 91, and is electrically connected to the common path 80. The first branch line 81 is a path that guides the power supplied from the connecting unit 91 (i.e., the external power source 110) to the common path 80. When the energy storage unit 90 is being charged, the external power source 110 is connected to the connecting unit 91.

[0076] The second branch line 82 is disposed between the energy storage unit 90 and the first load 92, and is electrically connected to the common path 80. The second branch line 82 is the path that guides the power from the common path 80 to the first load 92.

[0077] The third branch line 83 is located between the energy storage unit 90 and the second load 93, and is electrically connected to the common path 80. The third branch line 83 is the path that guides power from the common path 80 to the second load 93.

[0078] The vehicle control device 1 is a device mounted on a vehicle 101 and used in the vehicle system 100. The vehicle control device 1 includes a first switch 11, a second switch 12, a third switch 13, a cut-off unit 14, current detection units 15, 16, and 17, and an ECU 20.

[0079] In this embodiment, the first switch 11, the second switch 12, and the third switch 13 are mechanical switches, but they can also be semiconductor switches such as FETs. The first switch 11 is located on the first branch line 81. The second switch 12 is located on the second branch line 82. The third switch 13 is located on the third branch line 83. The first switch 11, the second switch 12, and the third switch 13 are each controlled by an external ECU 94.

[0080] A cut-off section 14 is provided on the common path 80. The cut-off section 14 has the function of switching from an energized state that energizes the common path 80 to a cut-off state that cuts off the common path 80. In this embodiment, the cut-off section 14 is provided as a semiconductor switch such as a FET, but it can also be a mechanical switch. The cut-off section 14 is energized when in the ON state and cut off when in the OFF state. Alternatively, the cut-off section 14 can also be a circuit breaker that physically cuts off the path by being given a control signal. More specifically, it can also be a pyrotechnic circuit breaker (e.g., a PYRO fuse) that physically cuts off the path by causing a displacement section to move when a drive current is input. The cut-off section 14 is controlled by the ECU 20.

[0081] Current detection units 15, 16, and 17 are, for example, known current detection circuits. Current detection unit 15 detects the current value flowing through the first branch line 81. Current detection unit 15, for example, includes a shunt resistor provided in the first branch line 81 and a differential amplifier circuit that amplifies and outputs the voltage across the shunt resistor. Current detection unit 16 detects the current value flowing through the second branch line 82. Current detection unit 16, for example, includes a shunt resistor provided in the second branch line 82 and a differential amplifier circuit that amplifies and outputs the voltage across the shunt resistor. Current detection unit 17 detects the current value flowing through the third branch line 83. Current detection unit 17, for example, includes a shunt resistor provided in the third branch line 83 and a differential amplifier circuit that amplifies and outputs the voltage across the shunt resistor. The detection values ​​from current detection units 15, 16, and 17 are respectively input to ECU 20 and external ECU 94.

[0082] ECU 20 has a control unit 21 and a setting unit 22. The control unit 21 switches the cut-off unit 14 from an enabled state to a cut-off state when the cut-off condition is met. The setting unit 22 sets the cut-off condition. The setting unit 22 can set the cut-off condition based on whether a charging operation or a first discharging operation is being performed. The charging operation is the operation of allowing charging current based on power from the connection unit 91 (i.e., the external power source 110) to flow into the energy storage unit 90 when the first switch 11 is in the ON state. The first discharging operation is the operation of allowing discharging current to flow from the energy storage unit 90 to the first load 92 when the second switch 12 is in the ON state.

[0083] The charging and first discharging operations are performed as follows. The cut-off section 14 is normally in an enabled state, but switches to a cut-off state in the event of an overcurrent. That is, the charging operation is performed by electrically connecting the external power supply 110 to the first branch line 81 via the connection section 91 and switching the first switch 11 to the ON state. The first discharging operation is the operation of allowing discharge current to flow from the energy storage section 90 to the first load 92 while the second switch 12 is in the ON state. The first discharging operation is performed by switching the second switch 12 to the ON state.

[0084] The setting unit 22 can set the cut-off conditions based on which of the first and second discharge operations is being performed. The second discharge operation is the operation of causing discharge current to flow from the energy storage unit 90 to the second load 93 when the third switch 13 is in the on state. The second discharge operation is performed by switching the third switch 13 to the on state.

[0085] The setting unit 22 determines which of the following actions—charging, first discharging, and second discharging—is in progress based on whether the first switch 11, second switch 12, and third switch 13 are in an on or off state. The setting unit 22 receives signals from the external ECU 94 indicating whether the first switch 11, second switch 12, and third switch 13 are in an on or off state, and can then determine this. If the setting unit 22 determines that the first switch 11 is on, it determines that the charging action is in progress; if it determines that the second switch 12 is on, it determines that the first discharging action is in progress; and if it determines that the third switch 13 is on, it determines that the second discharging action is in progress.

[0086] The cut-off conditions include a first cut-off condition, a second cut-off condition, and a third cut-off condition. When the setting unit 22 determines that a charging operation is in progress, it sets the first cut-off condition. The first cut-off condition is that when the current flowing through the first branch line 81 exceeds a first threshold current, the cutting-off unit 14 is switched to the cut-off state before the first switch 11. Furthermore, when the setting unit 22 determines that a first discharging operation is in progress, it sets the second cut-off condition. The second cut-off condition is that when the current flowing through the second branch line 82 exceeds a second threshold current, the cutting-off unit 14 is switched to the cut-off state before the second switch 12. Furthermore, when the setting unit 22 determines that a second discharging operation is in progress, it sets the third cut-off condition. The third cut-off condition is that when the current flowing through the third branch line 83 exceeds a third threshold current, the cutting-off unit 14 is switched to the cut-off state before the third switch 13. The second threshold current is greater than the first threshold current. The second threshold current and the third threshold current are different from each other. The third threshold current can be less than or greater than the first threshold current.

[0087] The first cutting-off condition is determined based on the first cutting-off characteristic. More specifically, the first cutting-off condition is determined based on the first cutting-off characteristic and the current value flowing through the first branch line 81. The second cutting-off condition is determined based on the second cutting-off characteristic. More specifically, the second cutting-off condition is determined based on the second cutting-off characteristic and the current value flowing through the second branch line 82. The third cutting-off condition is determined based on the third cutting-off characteristic. More specifically, the third cutting-off condition is determined based on the third cutting-off characteristic and the current value flowing through the third branch line 83.

[0088] The first switch 11 is switched to the open state based on its first switch cutting-off characteristics. More specifically, the first switch 11 is switched to the open state based on its first switch cutting-off characteristics and the current value flowing through the first branch line 81. The second switch 12 is switched to the open state based on its second switch cutting-off characteristics. More specifically, the second switch 12 is switched to the open state based on its second switch cutting-off characteristics and the current value flowing through the second branch line 82. The third switch 13 is switched to the open state based on its third switch cutting-off characteristics. More specifically, the third switch 13 is switched to the open state based on its third switch cutting-off characteristics and the current value flowing through the third branch line 83.

[0089] like Figures 2 to 4 As shown, the first cut-off characteristic, second cut-off characteristic, third cut-off characteristic, first switch cut-off characteristic, second switch cut-off characteristic, and third switch cut-off characteristic are correspondence data representing the relationship between energizing time and current value. The correspondence data specifies the duration for which a state exceeding a certain current value will switch to the off state. The correspondence data can be a function or other operational expression, or it can be a table. For example, multiple current values ​​for judgment are predetermined. Whenever the actual current value exceeds the judgment current value, a timer corresponding to that judgment current value is activated. When the timer's operating time reaches the energizing time corresponding to the judgment current value, the state switches to off. Conversely, if the actual current value is lower than the judgment current value before reaching the energizing time, the timer is reset.

[0090] like Figure 2 As shown, during the energizing time of the first cut-off characteristic, the time corresponding to current values ​​below the first threshold current is longer than that of the first switch cut-off characteristic, and the time corresponding to current values ​​exceeding the first threshold current is shorter than that of the first switch cut-off characteristic. Therefore, when the control unit 21 sets the first cut-off condition, if the current value flowing through the first branch line 81 exceeds the first threshold current, it switches the cut-off unit 14 to the cut-off state before the first switch 11.

[0091] like Figure 3 As shown, during the energizing time of the second cut-off characteristic, the time corresponding to current values ​​below the second threshold current is longer than that of the second switch cut-off characteristic, and the time corresponding to current values ​​exceeding the second threshold current is shorter than that of the second switch cut-off characteristic. Therefore, when the control unit 21 sets the second cut-off condition, if the current value flowing through the second branch line 82 exceeds the second threshold current, it switches the cut-off unit 14 to the cut-off state before the second switch 12.

[0092] like Figure 4As shown, during the energizing time of the third cut-off characteristic, the time corresponding to current values ​​below the third threshold current is longer than that of the third switch cut-off characteristic, and the time corresponding to current values ​​exceeding the third threshold current is shorter than that of the third switch cut-off characteristic. Therefore, when the control unit 21 sets the third cut-off condition, if the current value flowing through the third branch line 83 exceeds the third threshold current, it switches the cut-off unit 14 to the cut-off state before the third switch 13.

[0093] ECU20 can communicate with external ECU94. When the setting unit 22 determines that both charging and first discharging operations are in progress, it outputs an error signal indicating an abnormality to the external ECU94. Additionally, when the control unit 21 determines that the cut-off condition has been met, it also outputs an error signal indicating an abnormality to the external ECU94.

[0094] Setting Department 22 Execution Figure 5 The controls shown. Figure 5 The control shown begins, for example, when ECU20 is started, and immediately restarts if it ends. Additionally, at startup, the cut-off section 14 is in the enabled state. Figure 5 In the control shown, firstly, in step S10, it is determined whether a charging operation is being performed. If the setting unit 22 determines that the charging operation is not being performed (if not in step S10), then in step S11, it determines whether a first discharging operation is being performed. If the setting unit 22 determines that the first discharging operation is not being performed (if not in step S11), then in step S12, it determines whether a second discharging operation is being performed. If the setting unit 22 determines that the second discharging operation is not being performed (if not in step S12), it returns to step S10. That is, the setting unit 22 repeatedly performs steps S11, S12, and S13 until any one of the charging operation, the first discharging operation, and the second discharging operation is performed.

[0095] If the setting unit 22 determines that a charging operation is in progress (if yes in step S10), in step S13, it determines whether a first discharging operation or a second discharging operation is in progress. If the setting unit 22 determines that neither the first discharging operation nor the second discharging operation is in progress (if no in step S13), it sets a first cutoff condition in step S14. If the setting unit 22 determines that either the first discharging operation or the second discharging operation is in progress (if yes in step S13), it outputs an error signal in step S15. That is, the setting unit 22 outputs an error signal even if it determines that a charging operation is in progress, but also determines that either the first discharging operation or the second discharging operation is in progress.

[0096] If the setting unit 22 determines that the first discharge operation is being performed (if yes in step S11), it determines in step S16 whether the second discharge operation is being performed. If the setting unit 22 determines that the second discharge operation is not being performed (if no in step S16), it sets the second cutoff condition in step S17. If the setting unit 22 determines that the second discharge operation is being performed (if yes in step S16), it outputs an error signal in step S15. That is, the setting unit 22 outputs an error signal when it determines that both the first and second discharge operations are being performed. If the setting unit 22 determines that the second discharge operation is being performed in step S12 (if yes in step S12), it sets the third cutoff condition in step S18.

[0097] The following description relates to the effects of the first embodiment.

[0098] The vehicle system 100 can perform a charging operation by switching the first switch 11 to the on state and a discharging operation by switching the second switch 12 to the on state. Furthermore, the vehicle control device 1 used in the vehicle system 100 can set cutoff conditions based on which operation—charging or discharging—is currently in progress. Therefore, according to this vehicle control device 1, overcurrent protection can be appropriately performed during both charging and discharging.

[0099] Furthermore, the setting unit 22 determines which action, either the charging or discharging action, is being performed based on whether the first switch 11 and the second switch 12 are in the on or off state.

[0100] Based on this structure, it is possible to simplify the determination of which action is being performed in the charging and discharging processes.

[0101] Furthermore, when the setting unit 22 determines that a charging operation is in progress, it sets a first cutting-off condition where, if the current flowing through the first branch line 81 exceeds a first threshold current, the cutting-off unit 14 is switched to the cutting-off state before the first switch 11. Additionally, when the setting unit 22 determines that a first discharging operation is in progress, it sets a second cutting-off condition where, if the current flowing through the second branch line 82 exceeds a second threshold current, the cutting-off unit 14 is switched to the cutting-off state before the second switch 12. Furthermore, the second threshold current is greater than the first threshold current.

[0102] According to the vehicle-mounted control device 1, during the charging operation, if the current flowing through the first branch line 81 exceeds the first threshold current, the cut-off section 14 can be switched to the cut-off state before the first switch 11. Similarly, during the first discharging operation, if the current flowing through the second branch line 82 exceeds the second threshold current, the cut-off section 14 can be switched to the cut-off state before the second switch 12. Furthermore, the second threshold current is greater than the first threshold current. Therefore, a first discharging operation with a larger current flow than during the charging operation is also possible. While the current value during the charging operation is easily imagined, the current value during the first discharging operation can easily vary depending on the usage conditions. For example, in electric vehicles and hybrid vehicles, high loads are easily applied during acceleration and uphill driving. According to this structure, even if a high load is applied during the first discharging operation and a current exceeding the first threshold current flows, the first discharging operation can continue without switching the cut-off section 14 to the cut-off state.

[0103] Furthermore, during the energizing time of the first cutoff characteristic, the time is longer than that of the first switch cutoff characteristic for current values ​​below the first threshold current, and shorter than that of the first switch cutoff characteristic for current values ​​exceeding the first threshold current. Similarly, during the energizing time of the second cutoff characteristic, the time is longer than that of the second switch cutoff characteristic for current values ​​below the second threshold current, and shorter than that of the second switch cutoff characteristic for current values ​​exceeding the second threshold current.

[0104] According to this structure, during the charging operation, if the current flowing through the first branch line 81 exceeds the first threshold current, the cutting-off section 14 can be switched to the cutting-off state before the first switch 11 based on the energizing time. Furthermore, during the first discharging operation, if the current flowing through the second branch line 82 exceeds the second threshold current, the cutting-off section 14 can be switched to the cutting-off state before the second switch 12 based on the energizing time.

[0105] Furthermore, when the setting unit 22 determines that the second discharge operation is being performed, it sets a third cutting-off condition whereby the current value flowing through the third branch line 83 exceeds the third threshold current, and the cutting-off unit 14 is switched to the cutting-off state before the third switch 13. In addition, the third threshold current is different from the second threshold current.

[0106] According to this structure, not only can the cutting conditions of the cutting section 14 be different depending on whether the charging operation is being performed or the first discharging operation is being performed, but the cutting conditions of the cutting section 14 can also be different depending on whether the first discharging operation is being performed or the second discharging operation is being performed.

[0107] Furthermore, the setting unit 22 outputs an abnormal signal when it determines that both the charging operation and the first discharging operation are being performed.

[0108] According to this structure, in a structure that does not assume that the charging action and the first discharging action will be performed in parallel, it is possible to notify the outside of an anomaly that the charging action and the first discharging action are being performed.

[0109] <Second Implementation>

[0110] The second embodiment differs from the first embodiment primarily in that a specific load is connected to a common path via a temperature fuse. Furthermore, the same reference numerals will be used for structures identical to those in the first embodiment, and detailed descriptions will be omitted.

[0111] Figure 6 The vehicle system 200 shown is a system mounted on a vehicle 201, and includes an energy storage unit 90, a connection unit 91, a load 292, a specific load 293, an external ECU 94, a common path 80, a first branch line 81, a second branch line 82, a specific branch line 283, and a vehicle control device 1B.

[0112] Load 292 is an example of the second switching unit. Load 292 is, for example, an electric motor. The electric motor is, for example, the driving motor of the vehicle 201 in the case of an electric vehicle or a hybrid vehicle. Load 292 receives power from the energy storage unit 90 via the common path 80 and the second branch line 82.

[0113] The specific load 293 is, for example, a high-voltage auxiliary unit, more specifically, an air conditioner, a heater, etc. The specific load 293 receives power from the energy storage unit 90 via the common path 80 and the specific branch line 283.

[0114] A common path 80 is provided between the energy storage unit 90 and multiple switching units (in this embodiment, the connection unit 91, the load 292, and the specific load 293).

[0115] The second branch line 82 is located between the energy storage unit 90 and the load 292, and is electrically connected to the common path 80. The second branch line 82 is the path that guides power from the common path 80 to the load 292.

[0116] A specific branch line 283 is disposed between the energy storage unit 90 and the specific load 293 and is electrically connected to the common path 80. The specific branch line 283 is the path that guides power from the common path 80 to the specific load 293.

[0117] The vehicle control device 1B is a device mounted on a vehicle 201 and used in the vehicle system 200. The vehicle control device 1B includes a first switch 11, a second switch 12, a temperature fuse 213, a cut-off section 214, current detection sections 15 and 16, and an ECU 20.

[0118] A temperature-sensitive fuse 213 is installed on a specific branch line 283 and blows when the melting temperature is exceeded. When the temperature-sensitive fuse 213 blows, the flow of current between the common path 80 and the specific load 293 is interrupted.

[0119] A cut-off unit 214 is provided on the common path 80. The cut-off unit 214 has the function of switching from an energized state (energizing the common path 80) to a cut-off state (cutting off the common path 80). In this embodiment, the cut-off unit 214 is a circuit breaker that physically cuts off the path by being given a control signal. More specifically, the cut-off unit 214 is a pyrotechnic circuit breaker (e.g., a PYRO fuse) that physically cuts off the path by causing a displacement unit to move when an input drive current is generated. The cut-off unit 214 is controlled by the ECU 20.

[0120] ECU 20 has a control unit 21 and a setting unit 22. The control unit 21 switches the cut-off unit 214 from an enabled state to a cut-off state when the cut-off condition is met. The setting unit 22 sets the cut-off condition. The setting unit 22 can set the cut-off condition based on whether a charging or discharging operation is currently being performed. The charging operation is the operation of allowing charging current based on power from the connection unit 91 (i.e., the external power source 110) to flow into the energy storage unit 90 when the first switch 11 is in the ON state. The discharging operation is the operation of allowing discharging current to flow from the energy storage unit 90 to the load 292 when the second switch 12 is in the ON state.

[0121] The charging and discharging operations are performed as follows. The cut-off section 214 is normally in the allowed state, but switches to the cut-off state in the event of an overcurrent. That is, the charging operation is performed by electrically connecting the external power supply 110 to the first branch line 81 via the connection section 91 and switching the first switch 11 to the on state. The discharging operation is the action of allowing discharge current to flow from the energy storage section 90 to the load 292 while the second switch 12 is in the on state. The discharging operation is performed by switching the second switch 12 to the on state.

[0122] The setting unit 22 determines which action, either charging or discharging, is being performed based on whether the first switch 11 and the second switch 12 are in an on or off state. The setting unit 22 receives signals from the external ECU 94 indicating whether the first switch 11 and the second switch 12 are in an on or off state, and can then determine whether the first switch 11 and the second switch 12 are in an on or off state. If the setting unit 22 determines that the first switch 11 is in an on state, it determines that the charging action is being performed; if it determines that the second switch 12 is in an on state, it determines that the discharging action is being performed.

[0123] The cut-off conditions include a first cut-off condition and a second cut-off condition. When the setting unit 22 determines that a charging operation is in progress, it sets the first cut-off condition. The first cut-off condition is that when the current flowing through the first branch line 81 exceeds a first threshold current, the cut-off unit 214 is switched to the cut-off state before the first switch 11. Furthermore, when the setting unit 22 determines that a discharging operation is in progress, it sets the second cut-off condition. The second cut-off condition is that when the current flowing through the second branch line 82 exceeds a second threshold current, the cut-off unit 214 is switched to the cut-off state before the second switch 12. The second threshold current is greater than the first threshold current.

[0124] The determination of whether the first cutting-off condition is met is based on the first cutting-off characteristic. More specifically, the determination of whether the first cutting-off condition is met is based on the first cutting-off characteristic and the current value flowing through the first branch line 81. The determination of whether the second cutting-off condition is met is based on the second cutting-off characteristic. More specifically, the determination of whether the second cutting-off condition is met is based on the second cutting-off characteristic and the current value flowing through the second branch line 82.

[0125] The first switch 11 is switched to the open state based on its first switch-off characteristics. More specifically, the first switch 11 is switched to the open state based on its first switch-off characteristics and the current value flowing through the first branch line 81. The second switch 12 is switched to the open state based on its second switch-off characteristics. More specifically, the second switch 12 is switched to the open state based on its second switch-off characteristics and the current value flowing through the second branch line 82.

[0126] The first cut-off characteristic, the second cut-off characteristic, the first switch cut-off characteristic, and the second switch cut-off characteristic are as described in the first embodiment.

[0127] ECU20 can communicate with external ECU94. When the setting unit 22 determines that both charging and discharging operations are in progress, it outputs an error signal to the external ECU94 indicating an abnormality. Additionally, when the control unit 21 determines that a cutoff condition has been met, it also outputs an error signal to the external ECU94 indicating an abnormality.

[0128] Setting Department 22 Execution Figure 7 The controls shown. Figure 7 The control shown begins, for example, when ECU20 is started, and immediately restarts if it ends. Additionally, at startup, the cut-off section 214 is in the enabled state. Figure 7 In the control shown, it is first determined in step S210 whether a charging operation is being performed. If the setting unit 22 determines that the charging operation is not being performed (if it is not performed in step S210), it determines in step S211 whether a discharging operation is being performed. If the setting unit 22 determines that the discharging operation is not being performed (if it is not performed in step S211), it returns to step S210. That is, the setting unit 22 repeatedly performs steps S211 and S212 until a charging operation or a discharging operation is performed.

[0129] If the setting unit 22 determines that a charging operation is in progress (if yes in step S210), it determines in step S213 whether a discharging operation is in progress. If the setting unit 22 determines that a discharging operation is not in progress (if no in step S213), it sets a first cutoff condition in step S214. If the setting unit 22 determines that a first discharging operation is in progress (if yes in step S213), it outputs an error signal in step S215. That is, the setting unit 22 outputs an error signal when it determines that a discharging operation is in progress even though it determines that a charging operation is in progress.

[0130] When the setting unit 22 determines that a discharge operation is being performed (if yes in step S211), it sets a second cut-off condition in step S217.

[0131] The following description relates to the effects of the second embodiment.

[0132] The vehicle system 200 can perform a charging operation by switching the first switch 11 to the on state and a discharging operation by switching the second switch 12 to the on state. Furthermore, the vehicle control device 1B used in the vehicle system 200 can set cut-off conditions based on which operation—charging or discharging—is currently in progress. Therefore, according to this vehicle control device 1B, overcurrent protection can be appropriately performed during both charging and discharging.

[0133] Furthermore, the vehicle-mounted control device 1B has a temperature fuse 213 installed on a specific branch line 283 that blows when the melting temperature is exceeded. According to this structure, in the event of a ground fault in a specific load 293, it is easy to prevent the impact from spreading to the energy storage unit 90, the connection unit 91, and the load 292.

[0134] <Other Implementation Methods>

[0135] This disclosure is not limited to the embodiments described above and illustrated in the accompanying drawings. For example, the features of the embodiments described above or later can be combined in all possible ways without contradiction. Furthermore, any feature in the embodiments described above or later may be omitted unless explicitly stated as an essential feature. Moreover, the embodiments described above can also be modified as follows.

[0136] In the first embodiment described above, the structure for the ECU to identify the on / off states of the first switch, the second switch, and the third switch is configured such that the setting unit receives signals indicating the on / off states of the first switch, the second switch, and the third switch from an external ECU and performs identification based on these signals. However, other structures are also possible. For example, the control unit may control the first switch, the second switch, and the third switch, and the on / off states of the first switch, the second switch, and the third switch may be identified based on the control state of the control unit. Alternatively, the structure may detect the voltage and current values ​​of the first branch line, the second branch line, and the third branch line, and identify the on / off states of the first switch, the second switch, and the third switch based on these detected values. Furthermore, a structure combining these elements may also be used.

[0137] In the second embodiment described above, the structure for the ECU to identify the on / off states of the first and second switches is configured such that the setting unit receives signals indicating the on / off states of the first and second switches from an external ECU and performs identification based on these signals. However, other structures are also possible. For example, as a structure where the control unit controls the first and second switches, the on / off states of the first and second switches can be identified based on the control state of the control unit. Alternatively, it can be configured to detect the voltage and current values ​​of the first and second branch lines and identify the on / off states of the first and second switches based on these detected values. Furthermore, a structure combining these methods is also possible.

[0138] In the first embodiment described above, an abnormal signal is output when it is determined that a first discharge action or a second discharge action is being performed while a charging action is being executed. However, it can also be configured to output an abnormal signal when it is determined that both a charging action and a first discharge action are being performed. On the other hand, it can also be configured not to output an abnormal signal even if it is determined that both a charging action and a second discharge action are being performed. That is, it can also be configured to output an abnormal signal only when it is determined that the first discharge action of the first discharge action or the second discharge action has been performed, while a charging action is being performed.

[0139] In the first embodiment described above, an abnormal signal is output when it is determined that both the first discharge action and the second discharge action are being performed. However, it can also be configured so that no abnormal signal is output even when both the first discharge action and the second discharge action are being performed.

[0140] In the first embodiment described above, the current values ​​flowing through the first branch line, second branch line, and third branch line are detected by current detection units respectively provided on the first branch line, second branch line, and third branch line. However, it is also possible to provide a current detection unit in a common path and detect the current values ​​flowing through the first branch line, second branch line, and third branch line based on this current detection unit. For example, the current value detected during the execution of the first operation may be detected as the current value flowing through the first branch line. Similarly, the current value detected during the execution of the second operation may be detected as the current value flowing through the second branch line. Furthermore, the current value detected during the execution of the third operation may be detected as the current value flowing through the third branch line. With this structure, the number of current detection units can be reduced.

[0141] In the second embodiment described above, the current values ​​flowing through the first branch line and the second branch line are detected by current detection units respectively provided on the first branch line and the second branch line. However, it is also possible to provide a current detection unit in a common path and detect the current values ​​flowing through the first branch line and the second branch line based on this current detection unit. For example, the current value detected during the execution of the first operation can be detected as the current value flowing through the first branch line. It is also possible to detect the current value detected during the execution of the second operation as the current value flowing through the second branch line. According to this structure, the number of current detection units can be suppressed.

[0142] In the above embodiments, the cut-off condition is determined based on the correspondence between energizing time and current value, but it can also be other conditions. For example, the cut-off condition can also exceed a predetermined cut-off threshold. More specifically, the first cut-off condition set during the execution of the charging operation is that the current value of the first branch line exceeds the first cut-off threshold, and the second cut-off condition set during the execution of the discharging operation can also be that the current value of the second branch line exceeds the second cut-off threshold. The first cut-off threshold can also be a value larger than the second cut-off threshold.

[0143] In the above embodiments, examples of setting the first action as a charging action and the second action as a discharging action have been described, but other structures are also possible. For example, both the first action and the second action can be discharging actions.

[0144] In the above embodiments, the second threshold current is greater than the first threshold current, but it can also be a structure where the second threshold current is less than the first threshold current.

[0145] Furthermore, the embodiments disclosed herein should be considered illustrative in all respects and not restrictive. The scope of the invention is not limited to the embodiments disclosed herein, and is intended to include all modifications within the scope set forth in the claims or their equivalents.

[0146] Label Explanation

[0147] 1: Vehicle-mounted control device

[0148] 1B: Vehicle-mounted control device

[0149] 11: First Switch

[0150] 12: Second switch

[0151] 13: Third Switch

[0152] 14: Cut-off section

[0153] 15: Current Detection Section

[0154] 16: Current Detection Unit

[0155] 17: Current Detection Section

[0156] 18: Current Detection Section

[0157] 20: ECU

[0158] 21: Control Department

[0159] 22: Setting Department

[0160] 80: Shared path

[0161] 81: First branch line

[0162] 82: Second branch line

[0163] 83: Third Branch Line

[0164] 90: Battery Storage Department

[0165] 91: Connecting section (first switching section)

[0166] 92: First load (second switching unit, load)

[0167] 93: Second load (third switching unit)

[0168] 94: External ECU

[0169] 100: In-vehicle system

[0170] 101: Vehicles

[0171] 110: External power supply

[0172] 111: Charging plug

[0173] 112: Charging cable

[0174] 200: In-vehicle system

[0175] 201: Vehicle

[0176] 213: Temperature fuse

[0177] 214: Cut-off section

[0178] 283: Specific branch line

[0179] 292: Load (Second Switching Unit)

[0180] 293: Specific load.

Claims

1. A vehicle-mounted control device for use in a vehicle system, the vehicle system comprising: a power storage unit; a plurality of switching units for exchanging power with the power storage unit; a common path disposed between the power storage unit and the plurality of switching units; a first branch line disposed between a first switching unit of the plurality of switching units and the common path, and electrically connected to the common path; a second branch line disposed between a second switching unit of the plurality of switching units and the common path, and electrically connected to the common path; and a first switch disposed on the first branch line; The second switch is installed on the second branch line; The cutting-off section switches from a state that allows the flow of current in the common path to a state that cuts off the flow of current in the common path, wherein... The vehicle-mounted control device has the following features: The control unit, when the cutting-off condition is met, switches the cutting-off unit from the permitted state to the cutting-off state; and The setting unit sets the cutting conditions. The setting unit sets the cutting-off condition based on which of the first and second actions is currently being performed. The first action involves exchanging power between the energy storage unit and the first exchange unit when the first switch is on, and the second action involves exchanging power between the energy storage unit and the second exchange unit when the second switch is on. When the setting unit determines that the first action is being performed, it sets a first cutting-off condition included in the cutting-off condition; when it determines that the second action is being performed, it sets a second cutting-off condition included in the cutting-off condition. The first disconnection condition is that when the current flowing through the first branch line exceeds a first threshold current, the disconnection section is switched to the disconnection state before the first switch is switched to the open state. The second disconnection condition is that when the current flowing through the second branch line exceeds a second threshold current that is different from the first threshold current, the disconnection section is switched to the disconnection state before the second switch is switched to the open state. The first switch is switched to the open state based on its first switch disconnection characteristic. The second switch is switched to the open state based on its disconnection characteristic. The determination of whether the first cutting condition is met is based on the first cutting characteristic. The determination of whether the second cutting condition is met is based on the second cutting characteristic. The first switch-off characteristic, the second switch-off characteristic, the first switch-off characteristic, and the second switch-off characteristic are respectively defined by correspondence data representing the relationship between energizing time and current value. In the energizing time of the first cut-off characteristic, the time corresponding to current values ​​below the first threshold current is longer than that of the first switch cut-off characteristic, and the time corresponding to current values ​​exceeding the first threshold current is shorter than that of the first switch cut-off characteristic. In the energizing time of the second cut-off characteristic, the time corresponding to the current value below the second threshold current is longer than that of the second switch cut-off characteristic, and the time corresponding to the current value above the second threshold current is shorter than that of the second switch cut-off characteristic.

2. The vehicle-mounted control device according to claim 1, wherein, The setting unit determines which of the first and second actions is being executed based on whether the first and second switches are in an on or off state.

3. The vehicle-mounted control device according to claim 1, wherein, The first switching unit is a connection unit that is connected to an external power source via a charging cable. The second switching unit is the load. The shared path is both the discharge path from the energy storage unit and the charging path to the energy storage unit. The first branch line is the path that directs the power supplied via the connection to the common path. The second branch line is the path that directs power from the shared path to the load. The setting unit sets the cut-off condition based on which of the charging and discharging actions is being performed. The charging action, when the first switch is on, causes the charging current supplied via the connection unit to flow to the energy storage unit. The discharging action, when the second switch is on, causes the discharging current to flow from the energy storage unit to the load.

4. The vehicle-mounted control device according to claim 3, wherein, The second threshold current is greater than the first threshold current.

5. The vehicle-mounted control device according to claim 4, wherein, The vehicle-mounted system includes: a third branch line, disposed between the third switching unit of the plurality of switching units and the common path, and electrically connected to the common path; and a third switch, disposed on the third branch line. The third switching unit is the second load. When the third switch is in the ON state, a second discharge operation is performed to allow the discharge current to flow from the energy storage unit to the second load. When the setting unit determines that the second discharge operation is being performed, it sets a third cutoff condition included in the cutoff condition. The third disconnection condition is the condition that the disconnection section is switched to the disconnection state before the third switch is switched to the open state when the current value flowing through the third branch line exceeds the third threshold current. The third threshold current is different from the second threshold current.

6. The vehicle-mounted control device according to claim 5, wherein, If the setting unit determines that both the charging and discharging actions are in progress, it outputs an abnormal signal.

7. The vehicle-mounted control device according to claim 6, wherein, The vehicle-mounted system includes: a specific load, which is different from the switching unit and receives power from the energy storage unit; and a specific branch line, disposed between the specific load and the common path, and electrically connected to the common path. The vehicle-mounted control device also includes a temperature fuse, which is installed on the specific branch line and melts when the melting temperature is exceeded.

8. The vehicle-mounted control device according to claim 2, wherein, The first switching unit is a connection unit that is connected to an external power source via a charging cable. The second switching unit is the load. The shared path is both the discharge path from the energy storage unit and the charging path to the energy storage unit. The first branch line is the path that directs the power supplied via the connection to the common path. The second branch line is the path that directs power from the shared path to the load. The setting unit sets the cut-off condition based on which of the charging and discharging actions is being performed. The charging action, when the first switch is on, causes the charging current supplied via the connection unit to flow to the energy storage unit. The discharging action, when the second switch is on, causes the discharging current to flow from the energy storage unit to the load.

9. The vehicle-mounted control device according to claim 8, wherein, When the setting unit determines that the charging operation is in progress, it sets a first cutoff condition included in the cutoff condition; when it determines that the discharging operation is in progress, it sets a second cutoff condition included in the cutoff condition. The first disconnection condition is that when the current flowing through the first branch line exceeds a first threshold current, the disconnection section is switched to the disconnection state before the first switch is switched to the open state. The second disconnection condition is that when the current flowing through the second branch line exceeds the second threshold current, the disconnection section is switched to the disconnection state before the second switch is switched to the open state. The second threshold current is greater than the first threshold current.

10. The vehicle-mounted control device according to claim 9, wherein, The vehicle-mounted system includes: a third branch line, disposed between the third switching unit of the plurality of switching units and the common path, and electrically connected to the common path; and a third switch, disposed on the third branch line. The third switching unit is the second load. When the third switch is in the ON state, a second discharge operation is performed to allow the discharge current to flow from the energy storage unit to the second load. When the setting unit determines that the second discharge operation is being performed, it sets a third cutoff condition included in the cutoff condition. The third disconnection condition is the condition that the disconnection section is switched to the disconnection state before the third switch is switched to the open state when the current value flowing through the third branch line exceeds the third threshold current. The third threshold current is different from the second threshold current.

11. The vehicle-mounted control device according to claim 8, wherein, If the setting unit determines that both the charging and discharging actions are in progress, it outputs an abnormal signal.

12. The vehicle-mounted control device according to claim 1 or claim 2, wherein, The vehicle-mounted system includes: a specific load, which is different from the switching unit and receives power from the energy storage unit; and a specific branch line, disposed between the specific load and the common path, and electrically connected to the common path. The vehicle-mounted control device also includes a temperature fuse, which is installed on the specific branch line and melts when the melting temperature is exceeded.

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