Cut-off control device

Abstract

A cut-off control device is provided that can anticipate multiple overcurrent states and perform control suitable for each overcurrent state. The cut-off control device (30) controls the cut-off unit (34) in an on-board system (10) having a power path (31) between the power storage unit (91) and the load (94) and a cut-off unit (34). The cut-off unit (34) switches between a cut-off state and a de-cut-off state. The cut-off state cuts off the power supply from the power storage unit (91) side to the load (94) side in the power path (31). The on-board system (10) is a system in which the cut-off unit (34) has a first cut-off unit (34A) and a second cut-off unit (34B), and when the first cut-off unit (34A) is in the de-cut-off state, the second cut-off unit (34B) becomes the cut-off state when a first overcurrent state occurs in the power path (31). The cut-off control device (30) includes a control device (20) that instructs the first cut-off section (34A) to switch to a cut-off state when the power path (31) is in a second overcurrent state.

Description

Technical Field

[0001] This disclosure relates to a cut-off control device. Background Technology

[0002] Patent Document 1 discloses the following technology: if a collision of a vehicle is detected, a control system for the power path between a high-voltage battery and multiple loads divides the power path into a high-voltage battery side and multiple load sides.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: U.S. Patent No. 9,221,343 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] The technology disclosed in Patent Document 1 is insufficient in its countermeasures based on the view that the current flowing to the power path is in multiple overcurrent states, and cannot properly control each overcurrent state.

[0008] This disclosure is made based on the above circumstances, and its purpose is to provide a disconnection control device capable of assuming multiple overcurrent states and performing control suitable for each overcurrent state.

[0009] Methods for solving problems

[0010] The cut-off control device disclosed herein controls the cut-off unit in an on-board system having a power storage unit, a power path, and a cut-off unit. The power path is a path for transmitting power between the power storage unit and a load. The cut-off unit switches between a cut-off state and a released state, wherein the cut-off state cuts off the power supply from the power storage unit side to the load side in the power path.

[0011] The vehicle-mounted system is a system in which the cutting-off section has a first cutting-off section and a second cutting-off section, and when the first cutting-off section is in the released state, the second cutting-off section becomes the cutting-off state when a first overcurrent state occurs in the power path.

[0012] The cut-off control device includes a control unit that instructs the first cut-off section to switch to the cut-off state when the power path is in a second overcurrent state.

[0013] Invention Effects

[0014] According to this disclosure, it is possible to conceive of multiple overcurrent states and perform control suitable for each overcurrent state. Attached Figure Description

[0015] Figure 1 This is a block diagram illustrating an onboard system equipped with the cut-off control device according to Embodiment 1.

[0016] Figure 2 This is a flowchart illustrating the processing flow in the first device of the cut-off control device according to Embodiment 1.

[0017] Figure 3 This is a flowchart illustrating the processing flow in the second device of the cut-off control device according to Embodiment 1.

[0018] Figure 4 This is a block diagram illustrating an onboard system equipped with the cut-off control device according to Embodiment 2.

[0019] Figure 5 It is a graph illustrating the cutting characteristics of each cutting section and relay in Embodiment 2, as well as the permissible power characteristics in the power path.

[0020] Figure 6 This is a flowchart illustrating the cutting control process of the second cutting section based on cutting characteristics in the control device of the cutting control device according to Embodiment 2.

[0021] Figure 7 This is a flowchart illustrating the cutting control process of the first cutting section based on cutting characteristics in the control device of the cutting control device according to Embodiment 2.

[0022] Figure 8 This is a flowchart illustrating the cut-off control process of a relay based on cut-off characteristics in the control device of the cut-off control device according to Embodiment 2.

[0023] Figure 9 This is a flowchart illustrating the temperature-based cut-off control process in the control device of the cut-off control device according to Embodiment 2.

[0024] Figure 10 This is a block diagram illustrating an onboard system with cut-off control devices according to other embodiments. Detailed Implementation

[0025] [Description of embodiments of this disclosure]

[0026] First, let's illustrate this with examples of the implementation schemes disclosed herein.

[0027] [1] The cut-off control device of this disclosure controls the cut-off unit in an on-board system having a power storage unit, a power path, and a cut-off unit. The power path is a path for transmitting power between the power storage unit and a load. The cut-off unit switches between a cut-off state and a released state, whereby the cut-off state is a state in which power supplied from the power storage unit side to the load side in the power path is cut off. The on-board system is such that the cut-off unit has a first cut-off unit and a second cut-off unit, and when the first cut-off unit is in a released state, the second cut-off unit becomes in a cut-off state when a first overcurrent state occurs in the power path. The cut-off control device includes a control device that instructs the first cut-off unit to switch to the cut-off state when the power path is in a second overcurrent state.

[0028] The aforementioned [1] disconnection control device can be applied to a system that can maintain the first disconnection section in a deactivated state while switching the second disconnection section to a disconnection state when the power path is in a first overcurrent state. Furthermore, in the aforementioned system, the disconnection control device can switch the first disconnection section to a disconnection state to provide protection when the power path becomes in a second overcurrent state, and can operate the control separately in the first and second overcurrent states. Therefore, the aforementioned disconnection control device can anticipate multiple overcurrent states and perform control suitable for each overcurrent state.

[0029] [2] In the above-mentioned [1] cut-off control device, the control device can switch the first cut-off section to a cut-off state when the collision detection sensor detects a collision with the vehicle.

[0030] For example, the technology in Patent Document 1 can immediately stop the power supply from the high-voltage battery to multiple loads and prevent leakage to the vehicle body during a vehicle collision. However, the causes of leakage from the high-voltage battery to the vehicle body are not limited to vehicle collisions. Therefore, the technology in Patent Document 1 cannot prevent leakage from the high-voltage battery to the vehicle body caused by reasons other than vehicle collisions. In contrast, the cut-off control device described above [2] can cut off the power supply from the battery to the loads by considering not only vehicle collisions but also overcurrent conditions in the power path, effectively preventing leakage from the battery to the vehicle body.

[0031] [3] In the cut-off control device of [1] or [2] above, the vehicle system has a first detection unit and a second detection unit, the first detection unit detecting the state of the current flowing through the power path, and the second detection unit detecting the state of the current flowing through the power path. The control device can instruct the first cut-off unit to switch to the cut-off state if the detection result of either the first detection unit or the second detection unit indicates a second overcurrent state.

[0032] Even if either the first detection unit or the second detection unit fails, the above-mentioned [3] disconnection control device can continue to detect the current status in the power path using the other unit.

[0033] [4] In the above-mentioned [3] cut-off control device, the control device can notify the outside of the failure of the second detection unit if the second detection unit fails.

[0034] The aforementioned [4] cut-off control device can easily and appropriately control the vehicle's movement based on the malfunction of the second detection unit.

[0035] [5] In the cutting control device of [3] or [4] above, the control device can, in the event of a failure of the first detection unit, indicate the first cutting unit to switch to the cutting state based on the detection result of the second detection unit.

[0036] Even if the first detection unit fails, the above-mentioned [5] disconnection control device can use the second detection unit to continue to detect the current status in the power path and continue to control the switching of the first disconnection unit to the disconnection state.

[0037] [6] In any of the cutting-off control devices [1] to [5] above, the magnitude of the current flowing through the power path in the first overcurrent state is greater than or equal to a first threshold, and the magnitude of the current flowing through the power path in the second overcurrent state is greater than or equal to a second threshold. The first threshold can be smaller than the second threshold.

[0038] The aforementioned [6] cut-off control device can appropriately switch each cut-off section to the cut-off state in accordance with the magnitude of the current flowing into the power path.

[0039] [7] In any of the above-mentioned [2] to [5] and [6] which is directly or indirectly referenced in [2], the control device has a first device and a second device. The first device switches the first cut-off section to a cut-off state when the collision detection sensor detects a collision with the vehicle or when a second overcurrent state occurs, and the second device can switch the second cut-off section to a cut-off state when a first overcurrent state occurs.

[0040] The cutting control device described above [7] makes it easy to correspond the control device to each cutting part, and thus it is easy to perform switching control to the cutting state specifically for the characteristics of each cutting part.

[0041] [8] In the above-mentioned [7] cutting control device, if the first device fails, the second device can switch the second cutting section to the cutting state.

[0042] When the above-mentioned [8] cut-off control device falls into a situation where the control of the first device and the second device no longer holds, it switches the second cut-off section to the cut-off state, thus limiting the power supply from the energy storage section to the load when the redundancy of the control device cannot be maintained.

[0043] [9] In the above-mentioned [8] cut-off control device, if the first device fails, the second device can notify the outside of the failure of the first device.

[0044] The aforementioned [9] cut-off control device can easily and appropriately control the vehicle's movement in case of a malfunction of the first device.

[0045]

[10] In the cut-off control device of [1] above, the vehicle system has a detection unit that detects the state of the current flowing through the power path. The control device controls the cutting off of the first cut-off unit based on the detection result of the detection unit and a first cut-off characteristic, the first cut-off characteristic determining the time until the cut-off occurs when the current of each current value flows through the first cut-off unit. The control device controls the cutting off of the second cut-off unit based on the detection result of the detection unit and a second cut-off characteristic, the second cut-off characteristic determining the time until the cut-off occurs when the current of each current value flows through the second cut-off unit. The first overcurrent state is a state in which the current flowing through the power path and the time of current flowing through the power path satisfy the cut-off condition based on the second cut-off characteristic, and the second overcurrent state is a state in which the current flowing through the power path and the time of current flowing through the power path satisfy the cut-off condition based on the first cut-off characteristic. Compared with the first cut-off characteristic, the second cut-off characteristic allows for a shorter time until the cut-off occurs when the current of each current value flows.

[0046] The cutting control device described above

[10] can control the first cutting section and the second cutting section according to their respective cutting characteristics. Furthermore, the cutting control device can cut the second cutting section before the first cutting section, which is advantageous in usage environments where it is desirable to cut the second cutting section before the first cutting section.

[0047] The first cutting-off characteristic defines the time elapsed until cutting off when current of each current value flows to the first cutting section. For example, when the "current value flowing to the first cutting section" is set to I1 and the "time elapsed until cutting off" when current of I1 flows to the first cutting section is set to t1, the first cutting-off characteristic determines the relationship between current value I1 and time t1 for each current value, at least within a predetermined first current range. Furthermore, when a current of at least any current value within the first current range continues to flow to the first cutting section for a period of time elapsed or longer as defined in the first cutting-off characteristic corresponding to that current value, it is considered that "the cutting-off condition based on the first cutting-off characteristic is satisfied."

[0048] Similarly, the second cut-off characteristic defines the time elapsed until cut-off when current of each current value flows into the second cut-off section. For example, when the "current value flowing into the second cut-off section" is set to I2 and the "time elapsed until cut-off" when current of current value I2 flows into the second cut-off section is set to t2, the relationship between current value I2 and time t2 is determined for each current value, at least within a predetermined second current range. Furthermore, when a current of at least any current value within the second current range continues to flow into the second cut-off section for a period of time elapsed or longer as defined in the second cut-off characteristic corresponding to that current value, it is considered that "the cut-off condition based on the second cut-off characteristic is satisfied."

[0049]

[11] In the cut-off control device of

[10] above, the vehicle system has a relay that switches between a cut-off state and a release state. The control device controls the cut-off of the relay based on the detection result of the detection unit and a third cut-off characteristic, which determines the time until cut-off when current of each current value flows through the relay. Compared with the first and second cut-off characteristics, the time until cut-off when current of each current value flows is shorter.

[0050] The above-mentioned

[11] cut-off control device can prevent the relay from malfunctioning due to the electric arc generated in the relay when the relay is switched to the cut-off state, and switches the first cut-off section and the second cut-off section to the cut-off state in a way that protects the relay.

[0051] The third cutoff characteristic defines the time elapsed until the current of each value flows into the relay and is cut off. For example, if the "current value flowing into the relay" is set to I3 and the "time elapsed until the current of value I3 flows into the relay" is set to t3, the third cutoff characteristic determines the relationship between the current value I3 and time t3 for each current value, at least within a specified third current range. Furthermore, if, for at least any current value within the third current range, a current greater than or equal to that current value continuously flows into the relay for a period of time elapsed or longer as defined in the third cutoff characteristic corresponding to that current value, then the "cutoff condition based on the third cutoff characteristic is satisfied."

[0052] [Details of the embodiments of this disclosure]

[0053] <Implementation Method 1>

[0054] [Overview of the in-vehicle system]

[0055] With cutting control device 30 Figure 1The vehicle system 10 shown is configured as a vehicle power system, including a power storage unit 91, a power path 31, a cut-off unit 34, a detection unit 38, and a control device 20 provided in the cut-off control device 30. The vehicle system 10 is configured to apply voltage to the load 94 from the power storage unit 91 via the power path 31, which transmits power between the power storage unit 91 and the load 94.

[0056] The energy storage unit 91 is a DC power source that generates DC voltage, such as a lead-acid battery, LiB battery, alternator, or converter. The energy storage unit 91 is provided with a high-potential terminal and a low-potential terminal. The high-potential terminal is electrically connected to the power path 31, and the low-potential terminal is electrically connected to ground, for example. The energy storage unit 91 is configured to apply a predetermined output voltage to the power path 31.

[0057] Power path 31 is a power path that transmits power between the energy storage unit 91 and the load 94, and is electrically connected to both the energy storage unit 91 and the load 94.

[0058] Load 94 is an automotive electronic component, such as an electric motor, ECU, or ADAS component. Load 94 is electrically connected to power path 31.

[0059] In this disclosure, the "electrical connection" is preferably a structure in which the two connected objects are electrically connected in a manner that makes their potentials equal (a state in which current can flow). However, it is not limited to this structure. For example, the "electrical connection" can also be a structure in which electrical components exist between the two connected objects and the two connected objects are electrically connected.

[0060] The cutting-off section 34 has a first cutting-off section 34A and a second cutting-off section 34B. The cutting-off section 34 switches between a cutting-off state, in which power is supplied from the storage unit 91 side to the load 94 side in the power path 31, and a released state, in which the cutting-off state is released. The first cutting-off section 34A is inserted into the power path 31 on the storage unit 91 side, and the second cutting-off section 34B is inserted into the power path 31 on the load 94 side, in addition to the first cutting-off section 34A. For example, an explosive fuse is used for the first cutting-off section 34A. The first cutting-off section 34A is in the cutting-off state, in which power is supplied from the storage unit 91 side to the load 94 side in the power path 31, by receiving a drive signal D from the first device 20A of the control device 20 (described later), thus stopping the power supply from the storage unit 91 side to the load 94 side.

[0061] If the explosive fuse receives a drive signal D, it ignites the built-in propellant, and the explosive force of the propellant instantly cuts off the conductive path connecting the power path 31 on the battery storage unit 91 side and the power path 31 on the load 94 side. Therefore, compared with relays, the explosive fuse can cut off the power path 31 in a short time. The first cutting section 34A, which has switched to the cutting off state, does not release the cutting off state but switches to the de-energized state, allowing power to be supplied from the battery storage unit 91 side to the load 94 side.

[0062] For the second cut-off section 34B, a relay, FET, transistor, etc., may be used, for example. The second cut-off section 34B switches to a cut-off state by receiving a cut-off signal C1 from the second device 20B of the control device 20 (described later), in which it cuts off the supply of power from the energy storage unit 91 side to the load 94 side in the power path 31. The second cut-off section 34B switches to a deactivated state by receiving a conduction signal C2 from the second device 20B of the control device 20. The second cut-off section 34B in the deactivated state can supply power from the energy storage unit 91 side to the load 94 side via the power path 31. The time required for the second cut-off section 34B from receiving the cut-off signal C1 to making the power path 31 a cut-off state is longer than that of the first cut-off section 34A.

[0063] The detection unit 38 includes a first detection unit 38A and a second detection unit 38B. The first detection unit 38A is inserted into the power path 31 on the side closer to the energy storage unit 91 than the first cut-off unit 34A. The second detection unit 38B is inserted into the power path 31 on the side closer to the energy storage unit 91 than the first detection unit 38A. The first detection unit 38A and the second detection unit 38B include, for example, a resistor and a differential amplifier, and are configured to output the value of the current flowing through the power path 31 (specifically, the analog voltage corresponding to the value of the current flowing through the power path 31) as a current value A. In this way, the first detection unit 38A and the second detection unit 38B detect the state of the current flowing into the power path 31.

[0064] The absolute value of the current in the power path 31 that the first detection unit 38A can detect is larger than the absolute value of the current value A that the second detection unit 38B can detect. The input-output error of the first detection unit 38A is larger than that of the second detection unit 38B. This input-output error is the difference between the magnitude of the current flowing into the power path 31 and the current value A representing that magnitude. The delay time of the first detection unit 38A is shorter than that of the second detection unit 38B. This delay time is the time required from the input of the current flowing into the power path 31 to the output of the current value A. In other words, the second detection unit 38B can detect the current in the power path 31 with higher accuracy than the first detection unit 38A. Furthermore, the first detection unit 38A detects the current flowing into the power path 31 faster than the second detection unit 38B.

[0065] The cutting control device 30 is a device for controlling the cutting section 34. The control device 20 provided in the cutting control device 30 includes a first device 20A and a second device 20B. The first device 20A and the second device 20B are respectively composed of circuits and components capable of control, such as a microcomputer or an FPGA. The first device 20A can operate as a cutting drive device to switch the first cutting section 34A to a cutting state. The second device 20B can operate as a power monitoring device to switch the second cutting section 34B to a cutting state and a de-energized state.

[0066] The first device 20A is structured to receive a collision detection signal N, which is output from a collision detection sensor 50 installed inside the vehicle, indicating that a vehicle collision has been detected. The collision detection sensor 50 can be a known sensor such as an impact sensor. The collision detection sensor 50 does not output the collision detection signal N to the first device 20A if it does not detect a vehicle collision. When the collision detection sensor 50 detects a vehicle collision and outputs the collision detection signal N to the first device 20A, the first device 20A outputs a drive signal D to the first cut-off section 34A, instructing the first cut-off section 34A to switch to a cut-off state.

[0067] Furthermore, the first device 20A is structured to input the current value A in the power path 31 detected by the first detection unit 38A and the second detection unit 38B, respectively. The first device 20A controls the output of the drive signal D to the first cut-off unit 34A based on the detection result, i.e., the current value A, input from either the first detection unit 38A or the second detection unit 38B. Specifically, when the detection result, i.e., the current value A, from either the first detection unit 38A or the second detection unit 38B indicates a second overcurrent state, the first device 20A provides the drive signal D to the first cut-off unit 34A, instructing the first cut-off unit 34A to switch to a cut-off state. In other words, the first device 20A switches the first cut-off unit 34A to a cut-off state when the collision detection sensor 50 detects a vehicle collision or when a second overcurrent state occurs. It should be noted that the second overcurrent state will be described later.

[0068] Furthermore, the first device 20A is a structure capable of monitoring whether the first detection unit 38A has malfunctioned. When the first device 20A determines that the first detection unit 38A has not malfunctioned, it controls the output of the drive signal D to the first cut-off unit 34A based on the current value A input from the first detection unit 38A.

[0069] The first device 20A is configured to, when a malfunction is detected in the first detection unit 38A, output a drive signal D to the first cutting-off unit 34A based on the detection result of the second detection unit 38B, i.e., the current value A, thereby instructing the first cutting-off unit 34A to switch to a cutting-off state. Specifically, when a malfunction is detected in the first detection unit 38A, and the current value A input from the second detection unit 38B indicates a second overcurrent state, the first device 20A provides the drive signal D to the first cutting-off unit 34A, instructing the first cutting-off unit 34A to switch to a cutting-off state. When a malfunction is detected in the first detection unit 38A, the first device 20A outputs a first detection unit fault signal F1 to the second device 20B indicating that a malfunction has occurred in the first detection unit 38A.

[0070] An example of the structure for determining a fault in the first detection unit 38A within the first device 20A will be described. The first device 20A is configured to monitor the current value A input from the first detection unit 38A at predetermined time intervals. For example, the first device 20A is configured to store multiple current values ​​A input from the first detection unit 38A at predetermined time intervals. The first device 20A compares the average of the stored multiple current values ​​A with the current current value A input from the first detection unit 38A (i.e., the latest current value A). If the result of this comparison is that the difference between the current input current value A and the average of the stored multiple current values ​​A is greater than or equal to a predetermined value, the first device 20A determines that the first detection unit 38A has malfunctioned. In other words, the state in which the first detection unit 38A cannot output a current value A corresponding to the current in the power path 31 is a state in which the first detection unit 38A has malfunctioned.

[0071] Furthermore, the first device 20A is designed to determine whether it has malfunctioned. A malfunction of the first device 20A occurs when the collision detection sensor 50 detects a vehicle collision or a second overcurrent condition occurs, preventing the first cut-off section 34A from switching to the cut-off state or determining a malfunction in the first detection section 38A. The first device 20A is equipped with a monitoring unit 20C that monitors the status of each electronic component constituting the first device 20A. The monitoring unit 20C is, for example, a microcomputer. The monitoring unit 20C detects a malfunction in any of the electronic components constituting the first device 20A. When the monitoring unit 20C detects a malfunction, the first device 20A outputs a first device malfunction signal F2 to the second device 20B, indicating that it has malfunctioned.

[0072] The second device 20B receives the current value A in the power path 31 detected by the second detection unit 38B. If a first overcurrent condition occurs when the first cut-off unit 34A is in the deactivated state, the second device 20B provides a cut-off signal C1 to the second cut-off unit 34B, switching the second cut-off unit 34B to the deactivated state. If the current value A input from the second detection unit 38B is neither in the first overcurrent condition nor the second overcurrent condition, the second device 20B provides a conduction signal C2 to the second cut-off unit 34B, deactivating the second cut-off unit 34B.

[0073] [Regarding the first and second overcurrent states]

[0074] Here, the first overcurrent state and the second overcurrent state will be explained. In the first overcurrent state, the magnitude of the current flowing into the power path 31 is greater than or equal to a first threshold and less than a second threshold that is greater than the first threshold. That is, the first threshold is less than the second threshold. The first overcurrent state is determined in the second device 20B using the current value A input from the second detection unit 38B. Specifically, the second device 20B determines that the magnitude of the current value A input from the second detection unit 38B (i.e., the current flowing into the power path 31) is greater than or equal to the first threshold and less than the second threshold that is greater than the first threshold as equivalent to the first overcurrent state.

[0075] Furthermore, in the second overcurrent state, the magnitude of the current flowing into the power path 31 is greater than or equal to a second threshold. The second overcurrent state is determined in the first device 20A using the current value A input from the first detection unit 38A or the second detection unit 38B. Specifically, the first device 20A determines that the magnitude of the current value A input from the first detection unit 38A or the second detection unit 38B (i.e., the current flowing into the power path 31) is greater than or equal to the second threshold, which is equivalent to a second overcurrent state.

[0076] The second device 20B is configured to determine whether the second detection unit 38B has malfunctioned by monitoring the current value A input from the second detection unit 38B at predetermined time intervals. For example, the second device 20B is configured to store the current value A input from the second detection unit 38B multiple times at predetermined time intervals. The second device 20B compares the average of the stored multiple current values ​​A with the current value A input from the second detection unit 38B (i.e., the latest current value A). If the result of this comparison is that the difference between the current input current value A and the average of the stored multiple current values ​​A is greater than or equal to a predetermined value, the second device 20B determines that the second detection unit 38B has malfunctioned. In other words, the state in which the second detection unit 38B cannot output the current value A corresponding to the current in the power path 31 is a state in which the second detection unit 38B has malfunctioned.

[0077] The second device 20B is configured to output a second detection unit fault signal F3, indicating a malfunction in the second detection unit 38B, to notify the outside world of the malfunction. Furthermore, the second device 20B is configured to output the first detection unit fault signal F1 and the first device fault signal F2 to the outside world when the first device 20A receives the first detection unit fault signal F1 and the first device fault signal F2. In other words, the second device 20B notifies the outside world of a malfunction in the first device 20A. In the state where the second detection unit 38B malfunctions but the first detection unit 38A does not malfunction, the first device 20A can continue to control the output of the drive signal D to the first cut-off unit 34A based on the detection result, i.e., the current value A, received from the first detection unit 38A. In the case of a malfunction in the second detection unit 38B, for example, the second device 20B is configured to continue providing a conduction signal C2 to the second cut-off unit 34B.

[0078] The second detection unit fault signal F3, the first detection unit fault signal F1, and the first device fault signal F2, which are output to the outside, are, for example, output to the indicator control device 51 that controls the operation of the indicator 52, and then output to the indicator 52, a buzzer, etc., via the indicator control device 51. The indicator 52 is, for example, a light installed on the vehicle's instrument panel. Alternatively, these fault signals F1, F2, and F3 can also be output directly to the indicator 52 without going through the indicator control device 51, thereby directly activating the indicator 52. Furthermore, these fault signals F1, F2, and F3 can also be output to an external ECU.

[0079] [Regarding the operation of the control device]

[0080] Then, while referring to Figure 2 , 3 Here, we will explain an example of the operation of the control device 20. Figure 2 The flowchart shown illustrates the process executed by the first device 20A when the specified start conditions are met. Figure 3 The flowchart shown is the process performed by the second device 20B when the specified start conditions are met. Figure 2 , 3 The flowchart shown is repeated in parallel in the first device 20A and the second device 20B, respectively.

[0081] [Regarding the control in the first device]

[0082] While referring to Figure 2The control performed in the second device 20B will be explained below. First, in step S1, the ignition switch installed in the vehicle is switched from the off state to the on state. Next, when moving to step S2, the first device 20A determines whether the first detection unit 38A has malfunctioned.

[0083] Here, before proceeding to step S2, the first device 20A can also use the monitoring unit 20C to determine whether it has malfunctioned. If the monitoring unit 20C does not detect a malfunction, the first device 20A proceeds to step S2. Alternatively, if the monitoring unit 20C detects a malfunction, the first device 20A can output a first device malfunction signal F2 to the second device 20B, indicating that it has malfunctioned, and then end the process. Figure 2 The execution of the processing within.

[0084] If the first device 20A determines in step S2 that the first detection unit 38A has not malfunctioned (No in step S2), then proceed to step S3. After proceeding to step S3, the first device 20A uses the current value A from the first detection unit 38A to detect the current flowing into the power path 31.

[0085] Next, after moving to step S4, the first device 20A determines whether the current flowing into the power path 31 is a second overcurrent state. Specifically, the first device 20A determines whether the current value A detected by the first detection unit 38A in the power path 31 is above a second threshold. If the current value A is above the second threshold, the first device 20A determines that the current flowing into the power path 31 is a second overcurrent state (yes in step S4) and moves to step S5. After moving to step S5, the first device 20A sends a drive signal D to the first cut-off unit 34A and ends the process. Figure 2 The execution of the processing within.

[0086] It should be noted that if a collision detection signal N is input from the collision detection sensor 50, the first device 20A, regardless of which step it is currently executing, will immediately move to step S5, send a drive signal D to the first cutting section 34A, and end the process. Figure 2 The execution of the processing in the process. That is, when the first device 20A receives a collision detection signal N from the collision detection sensor 50 that detects a collision with the vehicle, it forcibly executes the interruption process of sending a drive signal D to the first cut-off unit 34A.

[0087] If the first device 20A determines in step S4 that the current flowing into the power path 31 is not in the second overcurrent state (no in step S4) when the current value A is less than the second threshold, then it moves to step S3. After moving to step S3, the first device 20A uses the current value A from the first detection unit 38A to detect the current flowing into the power path 31 again.

[0088] If the first device 20A determines in step S2 that the first detection unit 38A has malfunctioned (Yes in step S2), then proceeds to step S6. Upon proceeding to step S6, the first device 20A stops detecting the current of the first detection unit 38A. For example, even if a current value A is input from the first detection unit 38A, the first device 20A does not use that value. Next, upon proceeding to step S7, the first device 20A outputs a first detection unit fault signal F1, indicating that the first detection unit 38A has malfunctioned, to the second device 20B.

[0089] Upon proceeding to step S8, the first device 20A uses the current value A from the second detection unit 38B to detect the current flowing into the power path 31. In this case, the current value A from the second detection unit 38B is used by both the first device 20A and the second device 20B. That is, if the first detection unit 38A malfunctions, the first device 20A and the second device 20B, based on the current value A from the second detection unit 38B, respectively instruct the first cut-off unit 34A and the second cut-off unit 34B to switch to a cut-off state.

[0090] After moving to step S9, the first device 20A determines whether the current flowing into the power path 31 is a second overcurrent state. Specifically, the first device 20A determines whether the current value A of the power path 31 detected by the second detection unit 38B is above a second threshold. If the current value A of the power path 31 detected by the second detection unit 38B is above the second threshold, the first device 20A determines that the current flowing into the power path 31 is a second overcurrent state (yes in step S9) and moves to step S5. After moving to step S5, the first device 20A sends a drive signal D to the first cut-off unit 34A and ends. Figure 2 The execution of the processing within.

[0091] If the first device 20A determines in step S9 that the current flowing into the power path 31 is not in the second overcurrent state (no in step S9) when the current value A is less than the second threshold, then it moves to step S8. After moving to step S8, the first device 20A uses the current value A from the second detection unit 38B to detect the current flowing into the power path 31 again.

[0092] [Regarding the control in the second device]

[0093] While referring to Figure 3 The control performed in the second device 20B will be explained below. First, in step S1, the ignition switch installed in the vehicle is switched from the off state to the on state. Next, when moving to step S12, the second device 20B determines whether the second detection unit 38B has malfunctioned.

[0094] Here, before proceeding to step S12, the second device 20B can also determine whether a first detection unit fault signal F1 or a first device fault signal F2 has been input from the first device 20A. If neither the first detection unit fault signal F1 nor the first device fault signal F2 has been input from the first device 20A, the second device 20B proceeds to step S12. Alternatively, if either the first detection unit fault signal F1 or the first device fault signal F2 has been input from the first device 20A, the second device 20B can output the first detection unit fault signal F1 or the first device fault signal F2 to the outside, thus ending the process. Figure 3 The execution of the processing within.

[0095] If the second device 20B determines in step S12 that the second detection unit 38B has malfunctioned (Yes in step S12), then proceed to step S13. Upon proceeding to step S13, the second device 20B outputs a second detection unit fault signal F3 indicating a malfunction in the second detection unit 38B to the outside and terminates the process. Figure 3 The execution of the processing within.

[0096] If the second device 20B determines in step S12 that the second detection unit 38B has not malfunctioned (No in step S12), then proceed to step S14. After proceeding to step S14, the second device 20B uses the current value A from the second detection unit 38B to detect the current flowing into the power path 31.

[0097] Next, after moving to step S15, the second device 20B determines whether the current flowing into the power path 31 is a first overcurrent state. Specifically, the second device 20B determines whether the current value A, detected by the second detection unit 38B, representing the current flowing into the power path 31, is above a first threshold and below a second threshold that is larger than the first threshold. If the second device 20B determines that the current flowing into the power path 31 is a first overcurrent state (yes in step S15) when the current value A is above the first threshold and below the second threshold that is larger than the first threshold, then it moves to step S16. After moving to step S16, the second device 20B sends a cutoff signal C1 to the second cutoff unit 34B and ends the process. Figure 3 The execution of the processing within.

[0098] If the second device 20B determines in step S15 that the current flowing into the power path 31 is not in the first overcurrent state (no in step S15) when the current value A is less than the first threshold, then it moves to step S14. After moving to step S14, the second device 20B uses the current value A from the second detection unit 38B to detect the current flowing into the power path 31 again.

[0099] Next, the effect of this structure will be illustrated.

[0100] The cut-off control device 30 disclosed herein controls the cut-off unit 34 in an on-board system 10 having a battery storage unit 91, a power path 31, and a cut-off unit 34. The power path 31 is a path for transmitting power between the battery storage unit 91 and a load 94. The cut-off unit 34 switches between a cut-off state, in which power is supplied from the battery storage unit 91 side to the load 94 side in the power path 31, and a deactivated state, in which the cut-off state is deactivated. The on-board system 10 is a system in which the cut-off unit 34 has a first cut-off unit 34A and a second cut-off unit 34B, and the second cut-off unit 34B becomes a cut-off state when a first overcurrent state occurs in the power path 31 while the first cut-off unit 34A is in a deactivated state. The cut-off control device 30 includes a control device 20 that instructs the first cut-off unit 34A to switch to a cut-off state when the power path 31 is in a second overcurrent state. According to this structure, it can be applied to a system that can maintain the first cut-off unit 34A in a deactivated state while switching the second cut-off unit 34B to a cut-off state when the power path 31 is in a first overcurrent state. Furthermore, in the aforementioned system, the disconnection control device 30 can switch the first disconnection section 34A to a disconnection state to provide protection when the power path 31 becomes in a second overcurrent state, and can be used for control separately in the first and second overcurrent states. Therefore, the disconnection control device 30 can anticipate multiple overcurrent states and perform control suitable for each overcurrent state.

[0101] The control device 20 of the cut-off control device 30 of this disclosure instructs the first cut-off section 34A to switch to a cut-off state when the collision detection sensor 50 detects a vehicle collision. According to this structure, the power supply from the energy storage unit 91 to the load 94 can be cut off by taking into account not only the vehicle collision but also the state of the current in the power path 31, effectively preventing leakage of current from the energy storage unit to the vehicle body.

[0102] The vehicle-mounted system 10 disclosed herein includes a first detection unit 38A that detects the state of the current flowing in the power path 31 and a second detection unit 38B that detects the state of the current flowing in the power path 31. If the detection result of either the first detection unit 38A or the second detection unit 38B indicates a second overcurrent state, the control device 20 instructs the first cut-off unit 34A to switch to a cut-off state. According to this structure, even if either the first detection unit 38A or the second detection unit 38B fails, the cut-off control device 30 can continue to detect the state of the current in the power path 31 using the other.

[0103] In the event of a malfunction in the second detection unit 38B, the control device 20 of the cut-off control device 30 of this disclosure notifies the outside of the malfunction of the second detection unit 38B. According to this structure, the cut-off control device 30 can easily and appropriately control the vehicle's operation in response to a malfunction in the second detection unit 38B.

[0104] In the event of a malfunction in the first detection unit 38A, the control unit 20 of the cut-off control device 30 in this disclosure instructs the first cut-off unit 34A to switch to a cut-off state based on the detection result of the second detection unit 38B. According to this structure, even if the first detection unit 38A malfunctions, the cut-off control device 30 can continue to use the second detection unit 38B to detect the current state in the power path 31 and continue controlling the switching of the first cut-off unit 34A to the cut-off state.

[0105] In the cut-off control device 30 of this disclosure, the magnitude of the current flowing into the power path 31 in the first overcurrent state is greater than or equal to a first threshold, and the magnitude of the current flowing into the power path 31 in the second overcurrent state is greater than or equal to a second threshold, wherein the first threshold is smaller than the second threshold. According to this structure, the cut-off control device 30 can appropriately switch each cut-off section to a cut-off state corresponding to the magnitude of the current flowing into the power path 31.

[0106] The control device 20 of the cut-off control device 30 disclosed herein includes a first device 20A and a second device 20B. The first device 20A switches the first cut-off section 34A to a cut-off state when the collision detection sensor 50 detects a vehicle collision or when a second overcurrent condition occurs. The second device 20B switches the second cut-off section 34B to a cut-off state when a first overcurrent condition occurs. With this structure, the cut-off control device 30 can easily correspond the control device 20 to each cut-off section, thus facilitating switching control to the cut-off state specifically tailored to the characteristics of each cut-off section.

[0107] In the cut-off control device 30 of this disclosure, if the first device 20A malfunctions, the second device 20B notifies the outside of the malfunction of the first device 20A. According to this structure, the cut-off control device 30 can easily and appropriately control the vehicle's operation in response to a malfunction of the first device 20A.

[0108] <Implementation Method 2>

[0109] The vehicle-mounted system 110 with the cut-off control device 130 of Embodiment 2 differs from Embodiment 1 in several ways, including in the structure of the power path 131, the cut-off section 134, and the detection section 138, and in the inclusion of a relay 136 and a temperature detection section 137. For structures identical to those in Embodiment 1, the same reference numerals are used, and descriptions of their construction, function, and effects are omitted.

[0110] [Overview of the in-vehicle system]

[0111] With cutting control device 130 Figure 4 The vehicle-mounted system 110 shown includes an energy storage unit 91, a power path 131, a cut-off unit 134, a detection unit 138, a relay 136, a temperature detection unit 137, and a control device 120 (cut-off control device 130).

[0112] The power path 131 has a high-potential side power path 131A and a low-potential side power path 131B. The high-potential side terminal of the energy storage unit 91 is electrically connected to the high-potential side power path 131A. The low-potential side terminal of the energy storage unit 91 is electrically connected to the low-potential side power path 131B. The energy storage unit 91 generates a predetermined potential difference (i.e., output voltage) between the high-potential side power path 131A and the low-potential side power path 131B.

[0113] The high-potential side power path 131A is electrically connected to the positive terminal of the load 94. The low-potential side power path 131B is electrically connected to the ground terminal of the load 94.

[0114] The cutting section 134 has a first cutting section 134E and a second cutting section 134F. The first cutting section 134E has a first high-potential side cutting section 134A and a first low-potential side cutting section 134C. For the first high-potential side cutting section 134A and the first low-potential side cutting section 134C, for example, an exploding fuse is used. The second cutting section 134F has a second high-potential side cutting section 134B and a second low-potential side cutting section 134D. For the second high-potential side cutting section 134B and the second low-potential side cutting section 134D, for example, a FET is used.

[0115] The first high-potential side cutoff portion 134A and the second high-potential side cutoff portion 134B are inserted into the high-potential side power path 131A. The first high-potential side cutoff portion 134A is inserted into the high-potential side power path 131A closer to the energy storage unit 91 than the second high-potential side cutoff portion 134B, and the second high-potential side cutoff portion 134B is inserted into the high-potential side power path 131A closer to the load 94 than the first high-potential side cutoff portion 134A. The first low-potential side cutoff portion 134C and the second low-potential side cutoff portion 134D are inserted into the low-potential side power path 131B. The first low-potential side cutoff portion 134C is inserted into the low-potential side power path 131B closer to the energy storage unit 91 than the second low-potential side cutoff portion 134D, and the second low-potential side cutoff portion 134D is inserted into the low-potential side power path 131B closer to the load 94 than the first low-potential side cutoff portion 134C.

[0116] The first high-potential side cutoff section 134A and the first low-potential side cutoff section 134C are switched to the cutoff state upon receiving a drive signal D from the first device 20A of the control device 120. The second high-potential side cutoff section 134B and the second low-potential side cutoff section 134D are switched to the cutoff state upon receiving a cutoff signal C1 from the second device 20B of the control device 120. The second high-potential side cutoff section 134B and the second low-potential side cutoff section 134D are switched to the deactivated state upon receiving a conduction signal C2 from the second device 20B of the control device 20.

[0117] The detection unit 138 is inserted into the high-potential side power path 131A, which is closer to the load 94 than the second high-potential side cutoff unit 134B. The detection unit 138 includes, for example, a resistor and a differential amplifier, and is configured to output the value of the current flowing in the high-potential side power path 131A (specifically, the analog voltage corresponding to the value of the current flowing in the high-potential side power path 131A) as a current value A. In other words, the detection unit 138 detects the state of the current flowing in the power path 131A.

[0118] Relay 136 includes a high-potential side relay 136A and a low-potential side relay 136B. The high-potential side relay 136A and low-potential side relay 136B can be, for example, known contactors or mechanical relays. The high-potential side relay 136A is inserted into the high-potential side power path 131A, which is closer to the load 94 than the detection unit 138. The low-potential side relay 136B is inserted into the low-potential side power path 131B, which is closer to the load 94 than the second low-potential side cutoff unit 134D. The high-potential side relay 136A and low-potential side relay 136B are switched to the off state by receiving a cutoff signal C3 from the second device 20B of the control device 120. The high-potential side relay 136A and low-potential side relay 136B are switched to the off state by receiving a conduction signal C4 from the second device 20B of the control device 20.

[0119] The temperature detection unit 137 is configured to be, for example, a known temperature sensor, and is disposed near the power path 131 and the cut-off section 134. The temperature detection unit 137 is configured to output a voltage value representing the temperature at the placement location (i.e., the temperature near the power path 131 and the cut-off section 134) as a temperature value Vt and input it to the control device 120.

[0120] The control device 120 installed in the cutting control device 130 is composed of circuits and components capable of control, such as a microcomputer or FPGA. The control device 120 can perform cutting control based on cutting characteristics and cutting control based on temperature.

[0121] [Overview of Cut-off Control Based on Cut-off Characteristics]

[0122] exist Figure 5 The diagram shows the first cutting-off characteristics Fc1, second cutting-off characteristics Fc2, and third cutting-off characteristics Fc3 of the first cutting-off section 134E, the second cutting-off section 134F, and the relay 136, as well as the permissible current characteristic Fc4 of the power path 131. The horizontal axis corresponds to the current value A flowing to the high-potential side power path 131A. The vertical axis corresponds to the time that the current value A flows in the high-potential side power path 131A. The current value A flowing to the high-potential side power path 131A is also the current value A flowing to the cutting-off section 134 and the relay 136. The time that the current value A flows to the high-potential side power path 131A is equivalent to the time that the current value A flows to the cutting-off section 134 and the relay 136.

[0123] The first cut-off characteristic Fc1, the second cut-off characteristic Fc2, the third cut-off characteristic Fc3, and the permissible current characteristic Fc4 are stored, for example, in the memory of the control device 120 in a form that can be compared with the current value A from the detection unit 138, such as table data and functions. In a graph where the horizontal axis is set to the current flowing through the power path 131 (each current value A) and the vertical axis is set to each time until cut-off at each current value A (i.e., a graph representing the current-time characteristics), the curve representing the first cut-off characteristic Fc1 is located above the curve representing the second cut-off characteristic Fc2. Furthermore, the curve representing the third cut-off characteristic Fc3 is located above the curves representing the first cut-off characteristic Fc1 and the second cut-off characteristic Fc2.

[0124] The first cut-off characteristic Fc1, the second cut-off characteristic Fc2, and the third cut-off characteristic Fc3 define the time intervals from when current of each current value A flows to the first cut-off section 134E, the second cut-off section 134F, and the relay 136, until the switch to the cut-off state. The permissible current characteristic Fc4 of the power path 131, for example, represents the current value A at which smoke appears from the power path 131 and the energizing time (i.e., the smoke characteristic). The permissible current characteristic Fc4 is obtained by combining the electrical characteristics of the electrical components such as wires and connectors in the power path 131. The permissible current characteristic Fc4 indicates that the larger the current value A flowing into the power path 131, the shorter the time it takes for the power path 131 to smoke.

[0125] like Figure 5As shown, compared to the first cutting characteristic Fc1 of the first cutting section 134E, the second cutting characteristic Fc2 of the second cutting section 134F has a shorter switching time to the cutting state when current of each current value A flows. For example, when the current H1(A) flows to the second cutting section 134F, the time T2 until the second cutting section 134F is cut off according to the second cutting characteristic Fc2 (hereinafter, also referred to as the cutting time T2 of the second cutting section 134F) is shorter than the time T1 until the first cutting section 134E is cut off according to the first cutting characteristic Fc1 when the current H1(A) flows to the first cutting section 134E (hereinafter, also referred to as the cutting time T1 of the first cutting section 134E). Similarly, the cutting time T4 of the second cutting section 134F when the current H2(A) flows to the second cutting section 134F is shorter than the cutting time T3 of the first cutting section 134E when the current H2(A) flows to the first cutting section 134E.

[0126] Furthermore, compared to the third cut-off characteristic Fc3 of the relay 136, the first cut-off characteristic Fc1 of the first cut-off section 134E and the second cut-off characteristic Fc2 of the second cut-off section 134F have shorter switching times when current flows for each current value A to the cut-off state. For example, when the current H1(A) flows to the first cut-off section 134E, the cut-off time T1 of the first cut-off section 134E and the cut-off time T2 of the second cut-off section 134F are shorter than the time T5 (hereinafter also referred to as the cut-off time T5 of the relay 136) until the relay 136 is cut off according to the third cut-off characteristic Fc3 when the current H1(A) flows to the relay 136. Similarly, when the current H2(A) flows to the first cut-off section 134E, the cut-off time T3 of the first cut-off section 134E and the cut-off time T4 of the second cut-off section 134F are shorter than the cut-off time T6 of the relay 136 when the current H2(A) flows to the relay 136.

[0127] Even considering either current H1 or H2, the cutting time of the second cutting section 134F when the current H(A) flows to the second cutting section 134F is shorter than the cutting time of the first cutting section 134E when the current H(A) flows to the first cutting section 134E. Furthermore, the cutting time of both the first cutting section 134E and the second cutting section 134F when the current H(A) flows to the first cutting section 134E is shorter than the cutting time of the relay 136 when the current H(A) flows to the relay 136.

[0128] Furthermore, compared to the time taken from the flow of current A into the power path 131 until smoke appears, the switching time to the cut-off state during the flow of current A is shorter in the first cut-off characteristic Fc1, the second cut-off characteristic Fc2, and the third cut-off characteristic Fc3. Therefore, by switching to the cut-off state according to the first cut-off characteristic Fc1, the second cut-off characteristic Fc2, and the third cut-off characteristic Fc3 respectively, smoke from the power path 131 can be prevented.

[0129] The first cutting-off characteristic Fc1, the second cutting-off characteristic Fc2, and the third cutting-off characteristic Fc3 indicate that the larger the current value A, the shorter the time it takes for the cutting-off section 134 and the relay 136 to switch to the cutting-off state. Among the first cutting-off characteristic Fc1, the second cutting-off characteristic Fc2, and the third cutting-off characteristic Fc3, the minimum current value A required to switch to the cutting-off state is B1, B2, and B3, respectively. B1, B2, and B3 are the cutting-off threshold values ​​for each cutting-off characteristic. Furthermore, the maximum current value A in each of the first cutting-off characteristic Fc1, the second cutting-off characteristic Fc2, and the third cutting-off characteristic Fc3 is U1, U2, and U3, respectively.

[0130] [Regarding the first overcurrent state, the second overcurrent state, and the third overcurrent state]

[0131] The first overcurrent state is determined in the control device 120 using the detection result from the detection unit 138 and the second cutoff characteristic Fc2. Specifically, the control device 120 determines that the first overcurrent state is present when the current value A input from the detection unit 138 is greater than or equal to the cutoff threshold B2, and the current value A and the duration of the current flowing into the power path 131 satisfy the cutoff condition based on the second cutoff characteristic Fc2 (being at a position larger than the curve representing the second cutoff characteristic Fc2). Here, "being at a position larger than the curve representing the second cutoff characteristic Fc2" means being at a position larger than... Figure 5 The curve representing the second cutting characteristic Fc2 is on the right.

[0132] Whether the current value A and the duration of current A flowing into the power path 131 satisfy the cutting-off condition based on the second cutting-off characteristic Fc2 can be determined by the following configuration. For example, if the current flowing into the power path 131 is a value greater than or equal to the cutting-off threshold B2, the time during which this current flows into the power path 131 is measured using a timer provided by the control device 120. Furthermore, it is determined whether the current value and the duration of current flowing into the power path 131 at this current value are at a position greater than that represented by the curve of the second cutting-off characteristic Fc2.

[0133] The second overcurrent state is determined in the control device 120 using the detection result from the detection unit 138 and the first cutoff characteristic Fc1. Specifically, the control device 120 determines that it is a second overcurrent state when the current value A input from the detection unit 138 is a value above the cutoff threshold B1 and the current value A and the time during which the current of current value A continues to flow into the power path 131 satisfy the cutoff condition based on the first cutoff characteristic Fc1 (being at a position larger than the curve representing the first cutoff characteristic Fc1).

[0134] Regarding whether the current value A and the duration of current A flowing into the power path 131 satisfy the cutoff condition based on the first cutoff characteristic Fc1, for example, if the current flowing into the power path 131 is a value greater than or equal to the cutoff threshold B1, the control device 120 uses a timer to measure the duration of this current flowing into the power path 131. Furthermore, it is determined whether the current value and the duration of current flowing into the power path 131 at that current value are at a position greater than that represented by the curve of the first cutoff characteristic Fc1.

[0135] Furthermore, if the detection result from the detection unit 138—that is, the current value A is greater than or equal to the cutoff threshold B3—and the current value A and the duration of its continuous flow into the power path 131 satisfy the cutoff condition based on the third cutoff characteristic Fc3 (being at a position larger than the curve representing the third cutoff characteristic Fc3), the control device 120 determines that it is a third overcurrent state. The determination of whether it is a third overcurrent state is made using a timer provided by the control device 120.

[0136] [Regarding cut-off control based on cut-off characteristics in control devices]

[0137] Then, while referring to Figures 6-8 Here, we will explain an example of a cut-off control based on the cut-off characteristics of the control device 120. Figures 6-8 The flowchart shown is a process that is repeatedly executed in parallel by the control device 120 when the specified start conditions are met.

[0138] [Regarding the cutting control of the second cutting section based on cutting characteristics in the control device]

[0139] First of all, Figure 6 In step S21, the ignition switch (start switch) of the vehicle is switched from the off state to the on state. Next, the process moves to step S22. Upon moving to step S22, the control device 120 uses the current value A from the detection unit 138 to detect the current flowing into the power path 131.

[0140] Next, after moving to step S23, the control device 120 determines whether the current flowing into the power path 131 is a normal current state. Specifically, if the control device 120 determines that the current value A is less than the cutoff threshold B2, it determines that the current flowing into the power path 131 is a normal current state (yes in step S23) and moves to step S22. If the control device 120 determines that it is a normal current state, it repeats the process of step S22. Alternatively, if the control device 120 determines that the current value A is greater than or equal to the cutoff threshold B2, it determines that the current flowing into the power path 131 is not a normal current state (no in step S23) and moves to step S24.

[0141] After moving to step S24, the control device 120 determines whether the current flowing into the power path 131 and the duration of that current flowing into the power path 131 satisfy the cutoff condition based on the second cutoff characteristic Fc2. Specifically, it determines whether the current value A of the current flowing into the power path 131 and the duration of the current with current value A (above the cutoff threshold B2) flowing continuously into the power path 131 are at a position larger than the curve representing the second cutoff characteristic Fc2 (i.e., satisfying the cutoff condition based on the second cutoff characteristic Fc2). In step S24, the control device 120 determines that the current flowing into the power path 131 and the duration of that current flowing into the power path 131 satisfy the cutoff condition based on the second cutoff characteristic Fc2. Therefore, the control device 120 determines that it is a first overcurrent state and moves to step S25. Thus, if the current value A flowing into the power path 131 and the duration of the current flowing into the power path 131 satisfy the cut-off condition based on the second cut-off characteristic Fc2, the control device 120 determines that it is a first overcurrent state.

[0142] After moving to step S25, the control device 120 sends a cutting signal C1 to the second cutting section 134F and ends the process. Figure 6The execution of the processing in step S24. That is, the control device 120 controls the cutting off of the second cutting off unit 134F based on the detection result of the detection unit 138 and the second cutting-off characteristic Fc2. For example, at this time, if the current value A of the current flowing into the power path 131 and the duration of the current value A (above the cutting-off threshold B2) flowing into the power path 131 are at a position smaller than the curve representing the first cutting-off characteristic Fc1, the first cutting off unit 134E is in a deactivated state. That is, if a first overcurrent state occurs when the first cutting off unit 134E is in a deactivated state, the control device 120 provides a cutting-off signal C1 to the second cutting off unit 134F. In addition, if in step S24 the control device 120 determines that the current flowing into the power path 131 and the duration of the current flowing into the power path 131 do not meet the cutting-off condition based on the second cutting-off characteristic Fc2, then step S24 is executed repeatedly.

[0143] [Regarding the cutting control of the first cutting section based on cutting characteristics in the control device]

[0144] Figure 7 Steps S21 to S22 shown are Figure 6 Steps S21 to S22 are the same, so the explanation is omitted.

[0145] In step S33, the control device 120 determines whether the current flowing into the power path 131 is a normal current state. Specifically, if the control device 120 determines that the current value A is less than the cutoff threshold B1, it determines that the current flowing into the power path 131 is a normal current state (yes in step S33) and moves to step S22. If the control device 120 determines that it is a normal current state, it repeats the process of step S22. Alternatively, if the control device 120 determines that the current value A is greater than or equal to the cutoff threshold B1, it determines that the current flowing into the power path 131 is not a normal current state (no in step S33) and moves to step S34.

[0146] After moving to step S34, the control device 120 determines whether the current value A flowing into the power path 131 and the duration of the current flowing into the power path 131 at a current value A (above the cutoff threshold B1) are at a position greater than the curve representing the first cutoff characteristic Fc1 (i.e., the cutoff condition based on the first cutoff characteristic Fc1 is met). In step S34, the control device 120 determines that the current flowing into the power path 131 and the duration of the current flowing into the power path 131 meet the cutoff condition based on the first cutoff characteristic Fc1. Therefore, the control device 120 determines that it is a second overcurrent state and moves to step S35. Thus, the control device 120 determines that it is a second overcurrent state when the current value A flowing into the power path 131 and the duration of the current flowing into the power path 131 at the duration of the current value A meet the cutoff condition based on the first cutoff characteristic Fc1.

[0147] After moving to step S35, the control device 120 sends a drive signal D to the first cutting section 134E and ends the process. Figure 7 The processing in the process is executed. That is, the control device 120 controls the cutting of the first cutting unit 134E based on the detection result of the detection unit 138 and the first cutting characteristic Fc1. In addition, if in step S34 the control device 120 determines that the current flowing into the power path 131 and the time for the current to flow into the power path 131 do not meet the cutting condition based on the first cutting characteristic Fc1, then step S34 is executed repeatedly.

[0148] [Regarding the disconnection control of relays based on disconnection characteristics in control devices]

[0149] Figure 8 Steps S21 to S22 shown are Figure 6 , 7 Steps S21 to S22 are the same, so the explanation is omitted.

[0150] In step S43, if the control device 120 determines that the current value A is less than the cutoff threshold B3, it determines that the current flowing into the power path 131 is a normal current state (Yes in step S43) and moves to step S22. If the control device 120 determines that it is a normal current state, it repeats the process of step S22. Conversely, if the control device 120 determines that the current value A is greater than or equal to the cutoff threshold B3, it determines that the current flowing into the power path 131 is not a normal current state (No in step S43) and moves to step S44.

[0151] After moving to step S44, the control device 120 determines whether the current value A flowing into the power path 131 and the duration of the current flowing into the power path 131 at the current value A (above the cutoff threshold B3) are at a position greater than the curve representing the third cutoff characteristic Fc3 (i.e., the cutoff condition based on the third cutoff characteristic Fc3 is met). In step S44, the control device 120 determines that the current flowing into the power path 131 and the duration of the current flowing into the power path 131 meet the cutoff condition based on the third cutoff characteristic Fc3. Therefore, the control device 120 determines that it is a third overcurrent state and moves to step S45. Thus, the control device 120 determines that it is a third overcurrent state when the current value A flowing into the power path 131 and the duration of the current flowing into the power path 131 at the duration of the current value A meet the cutoff condition based on the third cutoff characteristic Fc3.

[0152] After moving to step S45, the control device 120 sends a cut-off signal C3 to the relay 136 and ends. Figure 8 The processing in the process is executed. That is, the control device 120 controls the relay 136 to cut off based on the detection result of the detection unit 138 and the third cut-off characteristic Fc3. In addition, if in step S44 the control device 120 determines that the current flowing into the power path 131 and the time for which the current flows into the power path 131 are not at a position greater than that of the curve representing the third cut-off characteristic Fc3, then step S44 is executed repeatedly. In this way, by performing the process in parallel... Figures 6-8 The control device 120 can control the cutting off of the first cutting-off section 134E, the second cutting-off section 134F, and the relay 136 respectively. Therefore, even if any of the first cutting-off section 134E, the second cutting-off section 134F, and the relay 136 fails, the power supply to the power path 131 can be reliably cut off.

[0153] [Overview of temperature-based shut-off control]

[0154] The control device 120 can use the current value A from the detection unit 138 as the energizing current I and substitute it into the equation 1 shown below, which relates to the heat release and heating of the power path 131, to calculate the rising temperature ΔTw of the power path 131.

[0155] ΔTw(n)=ΔTw(n-1)×exp(-Δt / τw)+Rthw×Rw(n-1)×I(n-1) 2 ×(1-exp(-Δt / τw))…(Equation 1)

[0156] Equation 1 consists of the heat-related terms of the electric path 131 (ΔTw(n-1)×exp(-Δt / τw)) and the heat-related terms of the electric path 131 (Rthw×Rw(n-1)×I(n-1)). 2 The formula is ×(1-exp(-Δt / τw)). Here, I(n) is the current value (A) of the nth (an integer greater than 1) sampling (detection) test. ΔTw(n) is the temperature rise (°C) of the power path 131 after n sampling tests. Rw(n) is the resistance (Ω) of the power path 131 after n sampling tests. Rw(0) is the resistance (Ω) of the power path 131 at a specified temperature To (e.g., 20°C). Rthw is the thermal resistance (°C / W) of the power path 131. τw is the heat dissipation time constant (s) of the power path 131. Δt is the sampling interval (specified time) (s).

[0157] [Regarding temperature-based shut-off control in the control device]

[0158] Next, while referring to Figure 9 Here, we will explain an example of temperature-based cut-off control of the control device 120. Figure 9 The flowchart shown is a process that is repeatedly executed by the control device 120 when the specified start conditions are met. Figure 9 The flowchart shown is, for example, with Figures 6-8 The process shown Figure 1 The process is repeated in parallel within the control device 120.

[0159] First of all, Figure 9 In step S21, the vehicle's ignition switch is switched from an off state to an on state. Next, the process moves to step S52. Upon moving to step S52, the control device 120 uses the current value A from the detection unit 138 to detect the current flowing into the power path 131. Simultaneously, the control device 120 uses the temperature value Vt from the temperature detection unit 137 to detect the temperature near the power path 131 and the cut-off unit 134.

[0160] Next, upon moving to step S53, the control device 120 calculates the rising temperature ΔTw of the power path 131 based on Equation 1, and adds the calculated rising temperature ΔTw to the reference temperature Tc to estimate the current temperature Tp of the power path 131. For example, the reference temperature Tc is the temperature value Vt input from the temperature detection unit 137 to the control device 120 when step S52 is first executed after the start switch (ignition switch) is switched from the off state to the on state. At this time, the temperature change ΔTs of the power path 131 per sampling interval (predetermined time) Δt is calculated, and the rising temperature ΔTw of the power path 131 is calculated using the temperature change ΔTs per sampling interval Δt. Here, the temperature change ΔTs per Δt is represented by Equation 2 shown below. Equation 2 is obtained by modifying Equation 1.

[0161] ΔTs=ΔTw(n)-ΔTw(n-1)

[0162] = (Rthw × Rw(n-1) × I(n-1) 2 -ΔTw(n-1))×(1-exp(-Δt / τw))…(Formula 2)

[0163] Next, after moving to step S54, the control device 120 compares the estimated current temperature Tp of the power path 131 with the predetermined upper limit temperature Tmax of the power path 131, and determines whether the temperature Tp of the power path 131 is smaller than the upper limit temperature Tmax. The upper limit temperature Tmax is stored, for example, as a constant in the memory of the control device 120. If the control device 120 determines that the temperature Tp of the power path 131 is smaller than the upper limit temperature Tmax (yes in step S54), the control device 120 moves to step S53 and executes step S23 again. Specifically, the temperature change ΔTs for the next sampling interval Δt is calculated. Then, the temperature change ΔTs for the sampling interval Δt is added to the previously calculated rising temperature ΔTw(n-1) of the power path 131, and the rising temperature ΔTw(n) of the power path 131 from the reference temperature Tc up to the present is newly calculated. The control device 120 adds the calculated rising temperature ΔTw(n) to the reference temperature Tc to obtain the current temperature Tp of the power path 131. The control device 120 repeatedly calculates the rising temperature ΔTw and estimates the temperature Tp of the power path 131 (step S53) and compares the temperature Tp of the power path 131 with the upper limit temperature Tmax (step S54) until the temperature Tp of the power path 131 reaches or exceeds the upper limit temperature Tmax. Alternatively, step S54 may compare the rising temperature ΔTw with a predetermined threshold value.

[0164] If the control device 120 determines that the temperature Tp of the power path 131 is not less than the upper limit temperature Tmax, that is, the temperature Tp of the power path 131 is above the upper limit temperature Tmax (No in step S54), it proceeds to step S55. After proceeding to step S55, the control device 120 sends a cut-off signal C1 to the second cut-off section 134F, switching the second cut-off section 134F to the cut-off state. Then, the process ends. Figure 9 The process involves cutting off the flow of current to the power path 131 to prevent further temperature rise in the power path 131. In other words, the control device 120 switches the second cut-off section 134F to a cut-off state based on the ambient temperature of the second cut-off section 134F. It should be noted that, along with the second cut-off section 134F, the control device 120 can also switch the first cut-off section 134E and the relay 136 to a cut-off state.

[0165] Next, the effect of this structure will be illustrated.

[0166] In the cut-off control device 130 of this disclosure, the vehicle system 110 includes a detection unit 138 that detects the state of the current flowing in the power path 131. The control device 120 controls the cutting off of the first cut-off unit 134E based on the detection results of the detection unit 138 and a first cut-off characteristic Fc1 that determines the time elapsed until the current of each current value A flows into the first cut-off unit 134E. The control device 120 controls the cutting off of the second cut-off unit 134F based on the detection results of the detection unit 138 and a second cut-off characteristic Fc2 that determines the time elapsed until the current of each current value A flows into the second cut-off unit 134F. A first overcurrent state is a state in which the current flowing into the power path 131 and the time elapsed for that current in the power path 131 satisfy a cut-off condition based on the second cut-off characteristic Fc2. A second overcurrent state is a state in which the current flowing into the power path 131 and the time elapsed for that current in the power path 131 satisfy a cut-off condition based on the first cut-off characteristic Fc1. Compared with the first cutoff characteristic Fc1, the second cutoff characteristic Fc2 has a shorter time until the current flows for each current value A until it is cut off.

[0167] According to this structure, the cutting control device 130 can control the first cutting section 134E and the second cutting section 134F according to their respective cutting characteristics. Furthermore, the cutting control device 130 can cut the second cutting section 134F before the first cutting section 134E, which is advantageous in usage environments where it is desirable to cut the second cutting section 134F before the first cutting section 134E.

[0168] In the cut-off control device 130 of this disclosure, the vehicle system 110 includes a relay 136 that switches between a cut-off state and a deactivated state. The control device 120 controls the cut-off of the relay 136 based on the detection results of the detection unit 138 and a third cut-off characteristic Fc3 that determines the time elapsed until cut-off when current flows to the relay for each current value A. Compared to the third cut-off characteristic Fc3, the first cut-off characteristic Fc1 and the second cut-off characteristic Fc2 have shorter times elapsed until cut-off when current flows for each current value A. According to this structure, the cut-off control device 130 can prevent the relay 136 from malfunctioning due to an arc generated within the relay 136 when it switches to the cut-off state. In other words, the first cut-off section 134E and the second cut-off section 134F can be switched to the cut-off state in a way that protects the relay 136.

[0169] In the cut-off control device 130 of this disclosure, the control device 120 switches the second cut-off section 134F to a cut-off state based on the ambient temperature of the second cut-off section 134F. According to this structure, the cut-off control device 130 can perform control that switches the second cut-off section 134F to a cut-off state taking into account the ambient temperature of the second cut-off section 134F, thus providing better protection for the power path 131.

[0170] <Other Implementation Methods>

[0171] This structure is not limited to the embodiments described above and the accompanying drawings. For example, the following embodiments are also included within the scope of this disclosure.

[0172] In Embodiment 1, a structure is disclosed in which the second device 20B outputs the first device fault signal F2 to the outside to notify the user when the first device 20A receives the first device fault signal F2. Not limited thereto, the second device may also switch the second cut-off section to a cut-off state when the first device receives the first device fault signal. According to this structure, the cut-off control device switches the second cut-off section to a cut-off state when it falls into a situation where the control of both the first and second devices is no longer valid. Therefore, it is possible to limit the power supply from the energy storage unit to the load when the redundancy of the control devices cannot be maintained.

[0173] In Implementation 1, the first overcurrent state is a state where the current value A in the power path 31 is above a first threshold and below a second threshold that is greater than the first threshold. However, the first overcurrent state can also be any current value in the power path that is above the first threshold. In other words, the range of the first threshold may also include the range above the second threshold.

[0174] In Embodiment 1, the current value A is compared with a first threshold and a second threshold in the first device 20A and the second device 20B, respectively, to determine the state of the current flowing in the power path 31. Not limited to this, the structure can also be as follows: in the first device and the second device, the differential value of the detected current is processed periodically and repeatedly, and the absolute value of the differential value is compared with a threshold to determine the state of the current flowing in the power path. Furthermore, the first threshold and the second threshold can be fixed values, or they can be changed according to the operating conditions of the load to determine the state of the current flowing in the power path.

[0175] In embodiment 1, a first device 20A and a second device 20B are provided. However, it is not limited to this; the first device and the second device may also be provided as a single control device.

[0176] A comparator can also be used as the detection unit. In this case, a specified high-level signal is output when the current value in the power path is above a specified threshold, and a specified low-level signal is output when the current value is below the specified threshold. Alternatively, a structure using a current transformer or the like can also be used.

[0177] In Embodiment 1, it is disclosed that when the monitoring unit 20C detects a fault, the first device 20A outputs a first device fault signal F2 to the second device 20B indicating that it has malfunctioned. However, it is not limited to this; it can also be a structure where the second device outputs a fault diagnosis indication signal to the first device, and the first device performs the operation of detecting a fault in the monitoring unit when the fault diagnosis indication signal is input.

[0178] Unlike implementation method 2, such as Figure 10 As shown, it can also be a structure in which the first low-potential side cutoff section and the second low-potential side cutoff section are not provided in the low-potential side power path 131B.

[0179] Unlike embodiment 2, it can also be a structure that only provides either the first cutting portion or the second cutting portion.

[0180] It should be considered that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the invention is not limited to the embodiments disclosed herein, but is indicated by the scope of the claims, and is intended to include all modifications within the same meaning and scope as the claims.

[0181] Explanation of reference numerals in the attached figures

[0182] 10, 110, 210… Vehicle system

[0183] 20…control device

[0184] 20A…First device (control device) (cut-off control device)

[0185] 20B…Second device (control device) (cut-off control device)

[0186] 20C… Surveillance Department

[0187] 30, 130… Cut-off control device

[0188] 31, 131… power paths

[0189] 131A…High-potential side power path (power path)

[0190] 131B…Low-potential side power path (power path)

[0191] 34, 134... Cut-off section

[0192] 34A, 134E… First cutting section (cutting section)

[0193] 34B, 134F… Second cutting section (cutting section)

[0194] 38, 138… Testing Department

[0195] 38A…First Inspection Department (Inspection Department)

[0196] 38B…Second Inspection Department (Inspection Department)

[0197] 50… Collision detection sensors

[0198] 51…Indicator Control Device

[0199] 52…indicator

[0200] 91…Electric Storage Department

[0201] 94…load

[0202] 134A… First high-potential side cutoff section (first cutoff section) (cutoff section)

[0203] 134B…Second high-potential side cut-off section (second cut-off section) (cut-off section)

[0204] 134C… First low-potential side cutoff section (first cutoff section) (cutoff section)

[0205] 134D…Second low-potential side cut-off section (second cut-off section) (cut-off section)

[0206] 136…relay

[0207] 136A…High-potential side relay

[0208] 136B…Low-potential side relay

[0209] 137…Temperature Detection Department

[0210] A…current value

[0211] B1, B2, B3… Cut-off thresholds

[0212] C1, C3... cut off signal

[0213] C2, C4... conduction signals

[0214] D…drive signal

[0215] F1… Fault signal for the first detection unit

[0216] F2…First device fault signal

[0217] F3…Second Detection Department Fault Signal

[0218] Fc1…First Cut-off Characteristic

[0219] Fc2…Second cutting characteristic

[0220] Fc3…Third cutting characteristic

[0221] Fc4…Permissible Current Characteristics

[0222] N…collision detection signal

[0223] U1, U2, U3... Maximum value

[0224] Vt…temperature value

Claims

1. A cut-off control device for controlling a cut-off unit in an on-board system having a power storage unit, a power path, and a cut-off unit, wherein the power path is a path for transmitting power between the power storage unit and a load, and the cut-off unit switches between a cut-off state and a released state, wherein the cut-off state is a state in which power supplied from the power storage unit side to the load side in the power path is cut off, wherein... The vehicle-mounted system is a system in which the cutting-off section has a first cutting-off section and a second cutting-off section, and when the first cutting-off section is in the released state, the second cutting-off section becomes the cutting-off state when a first overcurrent occurs in the power path. The cut-off control device includes a control unit that, when the power path is in a second overcurrent state, instructs the first cut-off section to switch to the cut-off state. When the collision detection sensor detects a vehicle collision, the control device instructs the first cutting-off section to switch to the cutting-off state. The control device has a first device and a second device. When the collision detection sensor detects a vehicle collision or when the second overcurrent state occurs, the first device switches the first cut-off section to the cut-off state. When the first overcurrent state occurs, the second device switches the second cutting-off section to the cutting-off state.

2. The cutting-off control device according to claim 1, wherein, The vehicle-mounted system includes a first detection unit and a second detection unit. The first detection unit detects the state of the current flowing through the power path, and the second detection unit detects the state of the current flowing through the power path. If the detection result of either the first detection unit or the second detection unit indicates the second overcurrent state, the control device instructs the first cutting-off unit to switch to the cutting-off state.

3. The cutting-off control device according to claim 2, wherein, If the second detection unit malfunctions, the control device will notify the outside of the malfunction.

4. The cutting-off control device according to claim 2 or 3, wherein, In the event of a malfunction in the first detection unit, the control device instructs the first cutting unit to switch to the cutting state based on the detection result of the second detection unit.

5. The cutting control device according to claim 1, wherein, In the event of a malfunction in the first device, the second device switches the second cutting section to the cutting state.

6. The cutting control device according to claim 5, wherein, In the event of a malfunction in the first device, the second device shall notify the outside world of the malfunction in the first device.

7. A cut-off control device for controlling a cut-off unit in an on-board system having a power storage unit, a power path, and a cut-off unit, wherein the power path is a path for transmitting power between the power storage unit and a load, and the cut-off unit switches between a cut-off state and a released state, wherein the cut-off state is a state in which power supplied from the power storage unit side to the load side in the power path is cut off, wherein... The vehicle-mounted system is a system in which the cutting-off section has a first cutting-off section and a second cutting-off section, and when the first cutting-off section is in the released state, the second cutting-off section becomes the cutting-off state when a first overcurrent occurs in the power path. The cut-off control device includes a control unit that, when the power path is in a second overcurrent state, instructs the first cut-off section to switch to the cut-off state. The on-board system includes a detection unit that detects the state of the current flowing through the power path. The control device controls the cutting of the first cutting unit based on the detection result of the detection unit and a first cutting characteristic, wherein the first cutting characteristic determines the time interval from when the current of each current value flows through the first cutting unit until cutting. The control device controls the cutting of the second cutting unit based on the detection result of the detection unit and a second cutting characteristic, wherein the second cutting characteristic determines the time interval from when the current of each current value flows through the second cutting unit until cutting. The first overcurrent state is a state in which the current flowing through the power path and the time for the current to flow through the power path satisfy the cutting-off condition based on the second cutting-off characteristic. The second overcurrent state is a state in which the current flowing through the power path and the time for the current to flow through the power path satisfy the cutting-off condition based on the first cutting-off characteristic. Compared with the first cutting-off characteristic, the second cutting-off characteristic has a shorter time until the current is cut off for each current value.

8. The cutting control device according to claim 7, wherein, The vehicle system includes a relay that switches between the off state and the released state. The control device controls the relay to cut off based on the detection results of the detection unit and the third cut-off characteristic, wherein the third cut-off characteristic determines the time interval from when current of each current value flows through the relay until it is cut off. Compared with the third cutoff characteristic, the first and second cutoff characteristics have shorter times until cutoff for each current value.

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