In-vehicle interrupting current supply device

Abstract

An in-vehicle breaking current supply device (10) comprises a transformer (20) having a first winding (21) and a second winding (22), a drive unit (12), and a capacitor (28). The drive unit (12) switches between an allowable state in which the energization of the first winding (21) is allowed and a cancellation state in which the allowable state is canceled. The capacitor (28) is electrically connected to an intermediate conductive path between the second winding (22) and a circuit breaker (6) and can receive power from the second winding (22). A charging current is supplied to the capacitor (28) from the second winding (22) side in response to the drive unit (12) alternately repeating switching between the allowable state and the cancellation state. When a switch (30) is turned on, the capacitor (28) is discharged, and a drive current flows to a current input unit (7).

Description

Technical Field

[0001] The present disclosure relates to an in-vehicle interrupting current supply device.

Background Art

[0002] Patent Document 1 discloses a drive circuit using a pulse transformer. The drive circuit disclosed in Patent Document 1 includes a power MOSFET that controls load power, a MOSFET provided in a gate circuit in front of the power MOSFET, and a pulse transformer that inputs a PWM signal to the gate circuit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a power supply system mounted on a vehicle, there is a type that is equipped with a circuit breaker capable of interrupting a power path. In this type of power supply system, when a breaking condition is satisfied, a breaking signal is given to the circuit breaker by a signal generation circuit to cause the circuit breaker to perform a breaking operation.

[0005] However, in a circuit breaker provided in a power path, there is a concern that a surge voltage may be generated near the circuit breaker during a breaking operation. If a voltage caused by the surge voltage enters the signal generation circuit side through a parasitic capacitance component, there is a concern that unexpected element breakdown may occur. As a countermeasure against such a problem, there is a configuration in which the signal generation circuit side and the circuit breaker side are insulated by a transformer or the like as in Patent Document 1.

[0006] However, when driving a circuit breaker that performs a breaking operation when an input current of a certain magnitude is input, there is a concern that components for insulating the signal generation circuit side and the circuit breaker side may become large.

[0007] One object of the present disclosure is to provide a technology that facilitates miniaturization of an in-vehicle interrupting current supply device capable of driving a circuit breaker while enhancing insulation between the drive unit side and the circuit breaker side.

Means for Solving the Problems

[0008] An in-vehicle interrupting current supply device according to the present disclosure is applied to an in-vehicle interrupting device including a circuit breaker and a switch provided in a power path and insulated from the power path, wherein the in-vehicle interrupting device to be applied operates such that energization of the current input portion is permitted in response to an ON operation of the switch, and the circuit breaker performs an interrupting operation of the power path. The in-vehicle interrupting current supply device is a transformer having a first winding portion and a second winding portion, a drive unit that switches between a permitted state in which energization of the first winding portion is permitted and a released state in which the permitted state is released, a capacitor electrically connected to an intermediate conductive path between the second winding portion and the circuit breaker and receiving power from the second winding portion, and has a charging current for the capacitor is supplied from the second winding portion side in response to the drive unit alternately repeating the switching between the permitted state and the released state, the capacitor is discharged in response to an ON operation of the switch, and a drive current flows through the current input portion.

Advantages of the Invention

[0009] The technology according to the present disclosure facilitates miniaturization of an in-vehicle interrupting current supply device capable of driving a circuit breaker while enhancing insulation between the drive unit side and the circuit breaker side.

Brief Description of the Drawings

[0010]

Figure 1

Mode for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be listed and exemplified.

[0012] 〔1〕Applied to an in-vehicle circuit breaker device including a circuit breaker and a switch having a current input part provided in a power line and insulated from the power line, The in-vehicle circuit breaker device to be applied is an in-vehicle circuit breaker current supply device that operates such that energization of the current input part is allowed in response to an on operation of the switch, and the circuit breaker performs a breaking operation of the power line. A transformer having a first winding part and a second winding part; A drive part that switches between a permitted state in which energization of the first winding part is allowed and a released state in which the permitted state is released; A capacitor electrically connected to an intermediate conduction path between the second winding part and the circuit breaker and receiving power from the second winding part; and In response to the drive part alternately repeating the switching between the permitted state and the released state, a charging current is supplied to the capacitor from the second winding part side, In response to an on operation of the switch, the capacitor is discharged, and a drive current flows through the current input part In-vehicle circuit breaker current supply device.

[0013] Due to the presence of the transformer, the in-vehicle circuit breaker current supply device according to the above [1] can enhance the insulation between the circuit breaker side and the drive part side. Further, this in-vehicle circuit breaker device can input not only the current directly supplied from the second winding part to the current input part, but also the discharge current from the capacitor to the current input part. Therefore, this in-vehicle circuit breaker device can achieve both a configuration that suppresses the size of the transformer and a configuration that can input a current of a certain magnitude to the current input part, and can easily miniaturize an in-vehicle circuit breaker current supply device that can drive the circuit breaker while enhancing the insulation between the drive part side and the circuit breaker side.

[0014] [2] It has a discharge circuit for discharging the capacitor, when the switch is in the OFF state, while the energization from the capacitor to the current input section is blocked, the capacitor is discharged by the discharge circuit The in-vehicle cut-off current supply device according to [1].

[0015] In the in-vehicle cut-off current supply device of the above [2], when the switch is in the OFF state, if the driving operation by the driving unit is stopped and the capacitor is discharged by the discharge circuit, the charge of the capacitor can be removed while blocking the energization to the circuit breaker.

[0016] [3] The current input section has a first terminal section and a second terminal section, the intermediate conductive path has a first conductive path provided between one end of the second winding section and the first terminal section, and a second conductive path provided between the other end of the second winding section and the second terminal section, one electrode of the capacitor is electrically connected to the first conductive path, and the other electrode is electrically connected to the second conductive path, the discharge circuit has a resistance section connected in parallel to the capacitor between the first conductive path and the second conductive path, when the switch is in the OFF state, as the driving unit alternately repeats switching between the allowable state and the release state, a charging current is supplied to the capacitor from the second winding section side while a current flows through the resistance section, when the driving unit maintains the release state when the switch is in the OFF state, a current flows from the capacitor to the resistance section The in-vehicle cut-off current supply device according to [2].

[0017] The in-vehicle cut-off current supply device of the above [3] can more simply realize a configuration capable of removing the charge of the capacitor by stopping the driving operation by the driving unit when the switch is in the OFF state. Moreover, when charging the capacitor when the switch is in the OFF state, a current can flow through the resistance section in parallel with the charging of the capacitor, so that the current can be made more stable.

[0018] 〔4〕The maximum value of the drive current supplied to the current input section in response to the ON operation of the switch is larger than the maximum value of the charging current supplied to the capacitor when the capacitor is charged. 〔1〕The in-vehicle cut-off current supply device according to any one of 〔1〕to 〔3〕.

[0019] The in-vehicle cut-off current supply device of 〔4〕above can easily reduce the size of the transformer because the maximum value of the charging current supplied to the capacitor when the capacitor is charged is suppressed.

[0020] 〔5〕The drive unit starts a drive operation that alternately repeats the allowable state and the release state in response to the start switch for starting the vehicle on which the in-vehicle cut-off device is mounted switching from the OFF state to the ON state, and stops the drive operation when the start switch is in the OFF state. 〔1〕The in-vehicle cut-off current supply device according to any one of 〔1〕to 〔4〕.

[0021] The in-vehicle cut-off current supply device of 〔5〕above can start charging the capacitor when the vehicle is in the starting state and prepare to perform the cut-off operation of the circuit breaker. On the other hand, when the vehicle is in the stopped state, the charging of the capacitor can be paused.

[0022] 〔6〕The circuit breaker is an explosive circuit breaker that cuts off the power path when a drive current flows through the current input section. 〔1〕The in-vehicle cut-off current supply device according to any one of 〔1〕to 〔5〕.

[0023] The in-vehicle cut-off current supply device of 〔6〕above can supply a drive current to the current input section to cause the explosive circuit breaker to perform a cut-off operation. This type of explosive circuit breaker is likely to generate a surge voltage near the explosive circuit breaker during the cut-off operation, but the in-vehicle cut-off current supply device is less likely to be affected by such a surge voltage on the drive unit side.

[0024] 〔7〕When the switch is switched from the off state to the on state in a state where the drive unit alternately repeats the switching between the allowable state and the release state, the capacitor discharges to the current input unit while current is being supplied from the second winding part. The in-vehicle cut-off current supply device according to any one of 〔1〕 to 〔6〕.

[0025] In the in-vehicle cut-off current supply device of 〔7〕 above, when the drive unit alternately repeats the switching between the allowable state and the release state, the discharge from the capacitor Current In addition, the current based on the second winding part can be combined.

[0026] 〔8〕The circuit breaker has an igniter into which the drive current supplied to the current input unit flows, The igniter explodes when the drive current of the required current value continuously flows for the required energization time, The circuit breaker operates to cut off the power path in response to the explosion operation of the igniter, When the capacitance of the capacitor is C, the output voltage from the second winding part is Vout, the required energization time is Tp, the required current value is Ip, the resistance value of the igniter is Rp, and the base of the natural logarithm is e, the following formula (1),

Formula

[0027] The in-vehicle cut-off current supply device of 〔8〕 above is more likely to cause the igniter to explode reliably when the switch is turned on in a state where the capacitor is fully charged.

[0028] 〔9〕The circuit breaker has an igniter into which the drive current supplied to the current input unit flows, The circuit breaker operates to cut off the power path in response to the explosion operation of the igniter, When the capacitance of the capacitor is C, the output voltage from the second winding part is Vout, and the required power supply amount for detonating the igniter is Ep, the following formula (2):

Formula

[0029] The above in-vehicle cut-off current supply device of (9) can more surely detonate the igniter when the switch is turned on in a state where the capacitor is fully charged.

[0030] (10) The circuit breaker has an igniter into which the drive current supplied to the current input part flows. The igniter detonates when the drive current of the required current value continuously flows over the required energization time. The circuit breaker operates to cut off the power path in response to the detonation operation of the igniter. When the capacitance of the capacitor is C, the output voltage from the second winding part is Vout, the required energization time is Tp, the required current value is Ip, the resistance value of the igniter is Rp, and the required power supply amount for detonating the igniter is Ep, the following formula (3):

Formula

[0031] The above in-vehicle cut-off current supply device of (10) can more surely detonate the igniter when the switch is turned on in a state where the capacitor is fully charged.

[0032] <First Embodiment>

[0033] 1. Outline of In-vehicle System 1 FIG. 1 shows an in-vehicle system 1 including an in-vehicle interrupting current supply device 10 according to the first embodiment. In the following description, the in-vehicle interrupting current supply device 10 is also referred to as the interrupting current supply device 10. The in-vehicle system 1 is a system mounted on a vehicle 100 and capable of supplying power to various loads. The vehicle 100 on which the in-vehicle system 1 is mounted is, for example, a vehicle such as an electric vehicle, a plug-in hybrid vehicle, or a hybrid vehicle, and may be other types of vehicles.

[0034] As shown in FIG. 1, the in-vehicle system 1 is a system mounted on the vehicle 100. In FIG. 1, the area of the vehicle 100 is conceptually shown by a dashed-dotted line frame. The in-vehicle system 1 includes a battery 4, an interrupting current supply device 10, an interrupt signal generation unit 40, an interrupting device 2, a start switch 50, and the like.

[0035] The start switch 50 corresponds to, for example, an ignition switch for starting the engine if the vehicle 100 is a plug-in hybrid vehicle or a hybrid vehicle. If the vehicle 100 is an electric vehicle, it corresponds to a power switch for starting the EV system.

[0036] The battery 4 is an in-vehicle storage battery and may be composed of a secondary battery such as a lead storage battery or a lithium-ion battery, or may be composed of other types of storage batteries. The battery 4 applies a predetermined DC voltage (for example, 12 V) between the conductive paths 5A and 5B when fully charged. Hereinafter, the output voltage of the battery 4 is denoted as V1.

[0037] The power path 9 is a conductive path through which electric power is transmitted. Although the use of the power path 9 is not limited, for example, it can be configured as a conductive path that supplies electric power to an in-vehicle load. The power path 9 includes a first power path 9A connected to one side of the circuit breaker 6 and a second power path 9B connected to the other side of the circuit breaker 6. The first power path 9A and the second power path 9B are short-circuited to each other when the circuit breaker 6 is in the conductive state and insulated from each other when the circuit breaker 6 is in the interrupted state. In FIG. 1, the connection destinations on the side opposite to the circuit breaker 6 in the first power path 9A and the second power path 9B are omitted. The power path 9 is, for example, a conductive path to which a voltage higher than the voltage applied between the conductive paths 5A and 5B is applied.

[0038] The interrupting device 2 is a device for interrupting the power path 9. The interrupting device 2 includes a switch 30 and a circuit breaker 6.

[0039] The switch 30 is constituted by a semiconductor switch such as a FET (Field Effect Transistor) or a mechanical relay. The switch 30 allows current to flow from the capacitor 28 side to the first terminal portion 7A side when it is in the on state and blocks current from flowing from the capacitor 28 side to the first terminal portion 7A side when it is in the off state. Specifically, the switch 30 is in the on state when the interruption signal generation unit 40 outputs an interruption signal (on signal), and is in the off state when the interruption signal generation unit 40 outputs a release signal (off signal). When the switch 30 is in the off state, energization through the switch 30 is blocked in both directions, and when the switch 30 is in the on state, energization through the switch 30 is allowed in both directions.

[0040] In the example of FIG. 1, the circuit breaker 6 is configured as a pyrotechnic circuit breaker. As the pyrotechnic circuit breaker, a well-known explosive fuse such as PyroFuse (registered trademark) can be suitably used. The circuit breaker 6 includes a current input section 7, conductor sections 8A, 8B, and 8C, an igniter 6A, and a displacement section (not shown). The current input section 7 has a first terminal section 7A and a second terminal section 7B, and is a section through which a current flows from the first terminal section 7A to the second terminal section 7B when the switch 30 is in an on state. The current input section 7 is insulated from the power path 9. The conductor section 8A is a terminal that is connected to the first power path 9A and short-circuits to the first power path 9A. The conductor section 8B is a terminal that is connected to the second power path 9B and short-circuits to the second power path 9B. The conductor section 8C is a conductor that short-circuits between the conductor section 8A and the conductor section 8B.

[0041] Igniter 6A is a part that functions to generate a small explosion when a current flows from first terminal portion 7A to second terminal portion 7B, and to move a displacement portion by this explosion. The displacement portion is held in a predetermined position before an explosion occurs in igniter 6A (when conductor portions 8A, 8B, 8C are short-circuited with each other), and when an explosion occurs in igniter 6A, the displacement portion is displaced toward conductor portion 8C by the explosion, and cuts conductor portion 8C to interrupt the current.

[0042] In this way, the circuit breaker 2 operates such that the circuit breaker 6 interrupts the power path 9 when the switch 30 is switched to the on state, allowing current to flow to the current input section 7 and causing a drive current to flow to the current input section 7 (specifically, when the drive current flows from the first terminal section 7A via the ignition section to the second terminal section 7B).

[0043] The cutoff signal generation unit 40 includes a signal generation device 41 and an insulating element 42. The signal generation device 41 is a device capable of performing an operation of applying a cutoff signal (on signal) to the switch 30 via a conductive path 44 and an operation of applying a release signal (off signal) to the switch 30 via the conductive path 44. The signal generation device 41 is electrically connected to the conductive path 43 and can apply a cutoff signal (on signal) and a release signal (off signal) to the conductive path 43. One of the cutoff signal and the release signal is a high-level signal, and the other is a low-level signal. The insulating element 42 is an element that transmits the signal applied to the conductive path 43 to the conductive path 44 while insulating the conductive path 43 and the conductive path 44. The insulation method of the insulating element 42 may be optical insulation, inductive insulation, or capacitive insulation. In any case, when a cutoff signal (on signal) is output from the signal generation device 41 to the conductive path 43, the cutoff signal (on signal) is applied to the switch 30 in a state where the signal generation device 41 and the switch 30 are insulated, and accordingly, the switch 30 performs an on operation.

[0044] The signal generation device 41 outputs the above release signal (off signal) when a predetermined condition for cutting off the power path 9 is satisfied. For example, the signal generation device 41 outputs the above release signal (off signal) in a normal state where the value of the current flowing through the power path 9 is equal to or less than a threshold value, and outputs the above cutoff signal (on signal) when an overcurrent state occurs where the value of the current flowing through the power path 9 exceeds the threshold value. Note that the predetermined condition for cutting off the power path 9 is not limited to this example. For example, the signal generation device 41 may be configured to output the above cutoff signal (on signal) when the vehicle 100 collides.

[0045] 2. Configuration of the cutoff current supply device 10 The cutoff current supply device 10 includes a drive unit 12, a transformer 20, a capacitor 28, and a resistance unit 29. The cutoff current supply device 10 is a part that functions as a supply source for flowing a drive current to the circuit breaker 6.

[0046] The drive unit 12 includes a drive device 13 and a switching element 14. The drive unit 12 has a function of switching between a permitted state that permits energization of the first winding portion 21 and a released state that releases this permitted state.

[0047] The drive device 13 includes a control device. This control device is an information processing device having an arithmetic function and an information processing function, and has, for example, a CPU, a storage unit, and the like. The drive device 13 outputs an on signal for operating the switching element 14 in the on state and an off signal for operating the switching element 14 in the off state. One of the on signal and the off signal is, for example, a high-level signal, and the other is, for example, a low-level signal.

[0048] The switching element 14 is constituted by a semiconductor switching element such as, for example, a FET (Field Effect Transistor). The switching element 14 operates in the on state when an on signal is applied from the drive device 13, and operates in the off state when an off signal is applied from the drive device 13. Note that the switching element 14 may be a switching element other than a FET (for example, a bipolar transistor).

[0049] The transformer 20 is a transformer having a first winding portion 21 and a second winding portion 22. Both the first winding portion 21 and the second winding portion 22 are configured as coils. When a current change occurs in the first winding portion 21, the transformer 20 generates a voltage corresponding to the current change in the first winding portion 21 in the second winding portion 22. The number of turns N1 of the first winding portion 21 may be larger or smaller than the number of turns N2 of the second winding portion 22. When the switching element 14 is in the on state, an input voltage Vin equivalent to the output voltage of the battery 4 is applied across both ends of the first winding portion 21. When the voltage across both ends of the second winding portion 22 is defined as the output voltage Vout, Vin / Vout = N1 / N2. That is, in response to the switching element 14 switching from the off state to the on state, an output voltage of Vout = Vin×N2 / N1 is generated in the second winding portion 22. turn The number of turns N2.

[0050] The first conductive path 51 is a conductive path provided between one end of the second winding portion 22 and the first terminal portion 7A. The second conductive path 52 is a conductive path provided between the other end of the second winding portion 22 and the second terminal portion 7B. The second conductive path 52 is a conductor portion that short - circuits the other end of the second winding portion 22, the other electrode of the capacitor 28, the other end of the resistance portion 29, and the second terminal portion 7B. In the first conductive path 51, the portion closer to the second winding portion 22 than the switch 30 short - circuits the one end of the second winding portion 22, one electrode of the capacitor 28, and one end of the resistance portion 29. The portion of the first conductive path 51 closer to the circuit breaker 6 than the switch 30 short - circuits to the first terminal portion 7A.

[0051] The capacitor 28 is an element that is electrically connected to the first conductive path 51 and the second conductive path 52, which are intermediate conductive paths between the second winding portion 22 and the circuit breaker 6, and receives power from the second winding portion 22. One electrode of the capacitor 28 is electrically connected to the first conductive path 51, and the other electrode is electrically connected to the second conductive path. When the switch 30 is in the on state, current can flow from the capacitor 28 to the first terminal portion 7A through the first conductive path 51.

[0052] The resistance portion 29 corresponds to an example of a discharge circuit. The resistance portion 29 has a function of discharging the capacitor 28. The resistance portion 29 is connected in parallel to the capacitor 28 between the first conductive path 51 and the second conductive path 52.

[0053] 3. Operation of the interrupting current supply device 10 The interrupting current supply device 10 performs a charging operation of the capacitor 28. When performing the charging operation, the drive device 13 alternately repeats an on signal and an off signal to the switching element 14, specifically, the drive device 13 gives a PWM signal with a high-level signal as the on signal and a low-level signal as the off signal to the switching element 14 to turn the switching element 14 on and off. In response to the switching element 14 switching from the off state to the on state, an input voltage Vin equivalent to the output voltage of the battery 4 is applied across both ends of the first winding portion 21, and in response to the switching element 14 switching from the on state to the off state, the application of the voltage from the battery 4 across both ends of the first winding portion 21 is released. By such on-off operation, the state where the output voltage V1 is applied across both ends of the first winding portion 21 and the state where the application of the output voltage V1 across both ends of the first winding portion 21 is released alternate. In response to such on-off operation, an output voltage of up to about V1×N2 / N1 is generated in the second winding portion 22. Thus, in response to the drive unit 12 alternately repeating the switching between the allowed state and the released state (that is, in response to alternately switching the switching element 14 between the on state and the off state), a charging current is supplied to the capacitor 28 from the second winding portion 22 side, and in this state, a slight current can flow through the resistance portion 29.

[0054] The drive unit 12 may start the above-described driving operation (a driving operation of alternately repeating the allowable state and the released state by alternately switching the switching element 14 between the on state and the off state) in response to the start switch 50 for starting the vehicle 100 being switched from the off state to the on state. Then, when the start switch 50 is in the on state, the above-described driving operation may be continued until it becomes the off state. And the drive unit 12 may stop the above-described driving operation when the start switch 50 is switched from the on state to the off state. In this example, when the start switch 50 is switched from the on state to the off state and maintained in the off state, since the drive unit 12 maintains the above-described released state, if the switch 30 is in the off state, the power supply from the capacitor 28 to the current input unit 7 is interrupted and the capacitor 28 is discharged by the resistance unit 29 (discharge circuit). On the other hand, when the start switch 50 is switched from the off state to the on state and maintained in the on state, since the drive unit 12 performs the above-described driving operation, if the switch 30 is in the off state, a charging current is supplied to the capacitor 28 from the second winding unit 22 side and a current flows through the resistance unit 29.

[0055] On the other hand, when the switch 30 is switched from the off state to the on state while the capacitor 28 is charged, the capacitor 28 is discharged in response to the on operation of the switch 30, and a drive current flows through the current input unit 7. For example, when the switch 30 is switched from the off state to the on state while the drive unit 12 is performing the above-described driving operation (a state of alternately repeating the switching between the allowable state and the released state), the capacitor 28 is discharged to the current input unit 7 while a current corresponding to the above-described driving operation is being supplied from the second winding unit 22 to the first conductive path 51. When a drive current is supplied from the capacitor 28 to the current input unit 7 in this way, a small explosion occurs in the igniter 6A, and the breaker 6 shuts off the power path 9.

[0056] Even when the switch 30 is switched from the off state to the on state while the drive unit 12 maintains the above-described released state, the capacitor 28 discharges to the current input unit 7. In this case, if the capacitor 28 is sufficiently charged before the discharge and a sufficient current is supplied to the current input unit 7, a small explosion occurs in the igniter 6A, and the breaker 6 shuts off the power path 9.

[0057] In the present embodiment, it is desirable that the maximum value of the drive current supplied to the current input unit 7 in response to the on-operation of the switch 30 is larger than the maximum value of the charging current supplied to the capacitor 28 during charging of the capacitor 28. The drive unit 12 applies PWM to the switching element 14 while adjusting the duty so as to have such a relationship.

[0058] In the present embodiment, the igniter 6A operates such that the above-described explosion occurs when a drive current of the "required current value" continuously flows over the "required energization time", and the breaker 6 operates to shut off the power path 9 in response to the explosion operation of the igniter 6A. In this example, when the capacitance of the capacitor 28 is C, the output voltage from the second winding portion 22 is Vout, the required energization time is Tp, the required current value is Ip, the resistance value of the igniter 6A is Rp, and the base of the natural logarithm is e, it is desirable that the capacitance C of the capacitor 28 is set so as to satisfy the following equation (1). If set in this way, by sufficiently charging the capacitor 28, a current of the required current value can continuously flow over the required energization time.

Equation

[0059] Furthermore, when the required supply power amount (required supply power amount for the igniter 6A) required to explode the igniter 6A is Ep, it is desirable that the capacitance C of the capacitor 28 is set so as to satisfy the following equation (2). If set in this way, by sufficiently charging the capacitor 28, a drive current exceeding the required supply power amount can be supplied during discharge of the capacitor 28.

Equation

[0060] Furthermore, it is desirable that the capacitance C of the capacitor be set so as to satisfy the following formula (3). With such a setting, the capacitor 28 is sufficiently charged, so that a drive current exceeding the required supply power amount can be supplied when the capacitor 28 is discharged during the above-described drive operation.

Formula

[0061] 4. Examples of Effects Due to the presence of the transformer 20, the interruption current supply device 10 can enhance the insulation between the circuit breaker 6 side and the drive unit 12 side. Furthermore, this in-vehicle interruption device 2 can input not only the current directly supplied from the second winding portion 22 to the current input portion 7, but also the discharge current from the capacitor 28 to the current input portion 7. Therefore, this in-vehicle interruption device 2 can achieve both a configuration with a reduced size of the transformer 20 and a configuration capable of inputting a current of a certain magnitude to the current input portion 7, and it is easy to miniaturize the in-vehicle interruption current supply device 10 that can drive the circuit breaker 6 while enhancing the insulation between the drive unit 12 side and the circuit breaker 6 side.

[0062] During the drive operation in which the drive unit 12 alternately repeats the switching between the allowed state and the released state, the interruption current supply device 10 can supply a charging current from the second winding portion 22 to the capacitor 28 via the first conductive path 51. Then, when the switch 30 is switched from the off state to the on state, a current can flow from the capacitor 28 to the first terminal portion 7A via the first conductive path 51, causing the circuit breaker 6 to perform an interruption operation.

[0063] Since the maximum value of the charging current supplied to the capacitor 28 is suppressed when the capacitor 28 is charged, the interruption current supply device 10 facilitates the miniaturization of the transformer 20.

[0064] When the vehicle 100 starts, the interrupting current supply device 10 can start charging the capacitor 28 and be prepared to perform the interrupting operation of the circuit breaker 6. On the other hand, when the vehicle 100 stops, the charging of the capacitor 28 can be suspended.

[0065] When the drive unit 12 repeatedly alternates between the allowed state and the released state, the interrupting current supply device 10 can Current add the current based on the second winding portion 22 in addition to the discharge from the capacitor 28.

[0066] The interrupting current supply device 10 can supply a drive current to the current input portion 7 to cause the pyrotechnic circuit breaker (circuit breaker 6) to perform an interrupting operation. In this type of pyrotechnic circuit breaker, a surge voltage is likely to occur near the pyrotechnic circuit breaker during the interrupting operation. However, in the in-vehicle interrupting current supply device 10, the influence of such a surge voltage hardly reaches the drive unit 12 side.

[0067] <Other Embodiments> The present disclosure is not limited to the embodiments described by the above description and drawings. For example, the features of the above-described or below-described embodiments can be combined in any non-contradictory manner. Also, any feature of the above-described or below-described embodiments can be omitted if it is not explicitly specified as essential. Furthermore, the above-described embodiments may be modified as follows.

[0068] A switch may be provided between the resistance portion 29 and the intermediate conductive path, and energization between the intermediate conductive path and the resistance portion 29 may be allowed when the switch is in the on state, and energization between the intermediate conductive path and the resistance portion 29 may be interrupted when the switch is in the off state.

[0069] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is not limited to the embodiments disclosed this time, but is intended to include all modifications within the scope indicated by the claims or within the scope equivalent to the claims.

Explanation of Signs

[0070] 1: In-vehicle system 2: In-vehicle cut-off device 4: Battery 5A: Conductive path 5B: Conductive path 6: Circuit breaker 6A: Igniter 7: Current input section 7A: First terminal section 7B: Second terminal section 8A: Conductor section 8B: Conductor section 8C: Conductor section 9: Power path 9A: First power path 9B: Second power path 10: In-vehicle cut-off current supply device 12: Driving section 13: Driving device 14: Switching element 20: Transformer 21: First winding section 22: Second winding section 28: Capacitor 29: Resistance section 30: Switch 40: Cut-off signal generation section 41: Signal generation device 42: Insulating element 43: Conductive path 44: Conductive path 50: Start switch 51: First conductive path 52: Second conductive path 100: Vehicle

Claims

1. Applied to an in-vehicle cutoff device including a circuit breaker and a switch, the circuit breaker having a current input portion provided in a power line and insulated from the power line, The in-vehicle cutoff device to which the application target is applied is an in-vehicle cutoff current supply device that operates such that energization to the current input portion is allowed in response to an ON operation of the switch, whereby the circuit breaker performs a cutoff operation of the power line. The in-vehicle cutoff current supply device includes: A transformer having a first winding portion and a second winding portion; A drive unit that switches between a permitted state in which energization to the first winding portion is allowed and a released state in which the permitted state is released; A capacitor electrically connected to an intermediate conduction path between the second winding portion and the circuit breaker and receiving power from the second winding portion; And has In response to the drive unit alternately repeating the switching between the permitted state and the released state, a charging current is supplied to the capacitor from the second winding portion side, In response to an ON operation of the switch, the capacitor is discharged and a drive current flows through the current input portion In-vehicle cutoff current supply device.

2. Having a discharge circuit for discharging the capacitor, When the switch is in an OFF state, while the energization from the capacitor to the current input portion is cut off, the capacitor is discharged by the discharge circuit The in-vehicle cutoff current supply device according to claim 1.

3. The current input portion has a first terminal portion and a second terminal portion, The intermediate conduction path has a first conduction path provided between one end of the second winding portion and the first terminal portion, and a second conduction path provided between the other end of the second winding portion and the second terminal portion, One electrode of the capacitor is electrically connected to the first conduction path, and the other electrode is electrically connected to the second conduction path, The discharge circuit has a resistance portion connected in parallel to the capacitor between the first conduction path and the second conduction path, When the switch is in an OFF state, in response to the drive unit alternately repeating the switching between the permitted state and the released state, a charging current is supplied to the capacitor from the second winding portion side while a current flows through the resistance portion, When the drive unit maintains the released state when the switch is in an OFF state, a current flows from the capacitor to the resistance portion The in-vehicle cutoff current supply device according to claim 2.

4. The maximum value of the drive current supplied to the current input section in response to the ON operation of the switch is greater than the maximum value of the charging current supplied to the capacitor during charging of the capacitor. The in-vehicle cutoff current supply device according to any one of claims 1 to 3.

5. The drive unit starts a drive operation that alternately repeats the allowable state and the release state in response to the start switch for starting the vehicle on which the in-vehicle cutoff device is mounted switching from the OFF state to the ON state, and stops the drive operation when the start switch is in the OFF state. The in-vehicle cutoff current supply device according to any one of claims 1 to 4.

6. The cutoff device is an explosive cutoff device that cuts off the power path when a drive current flows through the current input section. The in-vehicle cutoff current supply device according to any one of claims 1 to 5.

7. When the switch switches from the OFF state to the ON state while the drive unit is alternately repeating the switching between the allowable state and the release state, the capacitor discharges to the current input section from the capacitor while current is being supplied from the second winding section. The in-vehicle cutoff current supply device according to any one of claims 1 to 6.

8. The cutoff device has an igniter into which a drive current supplied to the current input section flows. The igniter explodes when the drive current of the required current value continuously flows for the required energization time. The cutoff device operates to cut off the power path in response to the explosion operation of the igniter. When the capacitance of the capacitor is C, the output voltage from the second winding section is Vout, the required energization time is Tp, the required current value is Ip, the resistance value of the igniter is Rp, and the base of the natural logarithm is e, the following formula (1): 【Number 1】 The capacitance C of the capacitor is set so as to satisfy the formula. The in-vehicle cutoff current supply device according to any one of claims 1 to 7.

9. The cutoff device has an igniter into which a drive current supplied to the current input section flows. The cutoff device operates to cut off the power path in response to the explosion operation of the igniter. When the capacitance of the capacitor is C, the output voltage from the second winding section is Vout, and the required supply power amount for exploding the igniter is Ep, the following formula (2): 【Number 2】 The capacitance C of the capacitor is set so as to satisfy the formula. The in-vehicle cutoff current supply device according to any one of claims 1 to 8.

10. The circuit breaker has an igniter into which a drive current supplied to the current input section flows, the igniter explodes when the drive current of a required current value continuously flows over a required energization time, the circuit breaker operates to cut off the power path in response to the explosion operation of the igniter, when the capacitance of the capacitor is C, the output voltage from the second winding section is Vout, the required energization time is Tp, the required current value is Ip, the resistance value of the igniter is Rp, and the required supply power amount for exploding the igniter is Ep, the capacitance C of the capacitor is set so as to satisfy the following formula (3): 【Number 3】 The in-vehicle cut-off current supply device according to claim 7.

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