High-voltage electrical loop safety protection system and automobile

Abstract

The utility model provides a high-voltage electrical loop safety protection system, which comprises a trigger unit, a smoke and fire power-off switch and a magnetically controlled switch, the trigger unit generates a trigger electric signal, an electric connection structure, a gas generator and a cut-off assembly are arranged in a shell of the smoke and fire power-off switch, and the electric connection structure is connected in series with a high-voltage electrical loop. The gas generator and the trigger unit form a first loop for conducting a trigger electric signal, the gas generator generates high-temperature and high-pressure gas when the first loop is conducted so as to push the cut-off assembly to disconnect the high-voltage electric loop, and the magnetically controlled switch comprises a switch part and a coupling part, and the switch part is connected with the first loop in series. The coupling component is arranged on a wire of the high-voltage electrical loop, the switch component and the coupling component jointly form a closed magnetic circuit which transmits magnetic force lines of the wire and is provided with an air gap, and the switch component moves relative to the coupling component so as to shorten and enlarge the air gap and connect and disconnect the first loop. According to the utility model, the smoke and fire power-off switch can quickly and reliably cut off an automobile high-voltage electrical loop.

Description

Technical Field

[0001] The utility model relates to the technical field of automobile circuit protection, in particular to a high-voltage electrical circuit safety protection system and an automobile. Background Art

[0002] The automotive high-voltage electrical circuit is not only the core component of the power system of new energy vehicles, but also plays a decisive role in improving vehicle performance, achieving energy management and ensuring the safety of passengers. In order to prevent safety accidents such as electrical fires caused by overload or short circuit of high-voltage electrical circuits, pyrotechnic power-off switches are usually used for protection. The principle is to use the internal gas generator to generate high-temperature and high-pressure gas to push the piston to quickly cut off the circuit.

[0003] At present, cars usually use Hall current sensors or Shunt shunt resistors to detect short-circuit current or overload current in the circuit, and the pyrotechnic power-off switch is usually connected to the car's BMS (battery management system). When the BMS collects abnormal current through the Hall current sensor or Shunt shunt resistor and analyzes and processes it, the BMS will send a signal to trigger the gas generator to quickly cut off the circuit.

[0004] However, since the processing flow from the current detection end to the BMS and then to the pyrotechnic power-off switch is time-consuming, the pyrotechnic power-off switch cannot cut off the circuit in time. Moreover, when the BMS operates abnormally, it is very easy to be triggered by mistake or even not triggered. Utility Model Content

[0005] Based on this, the purpose of the utility model is to provide a high-voltage electrical circuit safety protection system, which is intended to quickly and reliably enable a pyrotechnic power-off switch to cut off a high-voltage electrical circuit of a vehicle.

[0006] In a first aspect, the present utility model provides a safety protection system for a high-voltage electrical circuit, which includes a triggering unit, a pyrotechnic power-off switch, and a magnetic control switch. The triggering unit is used to generate continuous triggering electrical signals. The pyrotechnic power-off switch includes a housing and an electrical connection structure, a gas generator, and a cutting component disposed inside the housing. The electrical connection structure is connected in series in the high-voltage electrical circuit. A first circuit for conducting the triggering electrical signal is formed between the gas generator and the triggering unit. When the first circuit is turned on, the gas generator generates high-temperature and high-pressure gas to push the cutting component to disconnect the connection between the electrical connection structure and the high-voltage electrical circuit. The magnetic control switch includes a switch component and a coupling component. The switch component is connected in series in the first circuit. The coupling component is disposed on the wire of the high-voltage electrical circuit. The switch component and the coupling component together form a closed magnetic circuit for transmitting the magnetic lines of force generated by the wire. The closed magnetic circuit is provided with an air gap. The switch component can move relative to the coupling component to shorten the air gap when the intensity of the magnetic lines of force in the closed magnetic circuit exceeds a preset value and turn on the first circuit, and to expand the air gap and disconnect the first circuit when the intensity of the magnetic lines of force in the closed magnetic circuit is lower than the preset value.

[0007] The beneficial effects of the present utility model at least include: The magnetic control switch can detect whether an abnormal current is generated in the high-voltage circuit. When an abnormal current is generated, the magnetic control switch can turn on the first circuit in a relatively short time. Since the triggering electrical signal generated by the triggering unit is continuous, when the first circuit is turned on, the triggering electrical signal can be immediately transmitted to the pyrotechnic power-off switch, causing the pyrotechnic power-off switch to be immediately triggered, thereby quickly completing the cutting of the high-voltage circuit. Compared with the prior art, the entire triggering process does not require a sensor to detect the current, nor does it need to be analyzed and processed by the BMS. In this way, the triggering time can be shortened, the risk of false triggering can be reduced, and the entire triggering process does not require the design of an analysis and processing program or the provision of intelligent equipment, improving the reliability of the entire safety protection system.

[0008] In addition, according to the above safety protection system for a high-voltage electrical circuit of the present utility model, the following additional technical features may also be included:

[0009] Further, the coupling component includes a static magnetic yoke, and the switch component includes a selection on-off switch and a moving magnetic yoke. The static magnetic yoke is disposed around the circumference of the wire and is provided with a break interface. The on-off switch is connected in series in the first circuit. The moving magnetic yoke is linked with the on-off switch and is disposed close to the break interface to form a closed magnetic circuit between the static magnetic yoke and the moving magnetic yoke; when the magnetic attraction of the static magnetic yoke is greater than the preset value, the moving magnetic yoke moves away from the break interface, and the on-off switch closes the first circuit; and when the magnetic attraction of the static magnetic yoke is less than the preset value, the moving magnetic yoke approaches the break interface, and the on-off switch disconnects the first circuit.

[0010] Further, the triggering electrical signal is a voltage signal.

[0011] Further, the static magnetic yoke and the wire are insulated from each other.

[0012] Furthermore, the electrical connection structure includes a moving contact and relatively spaced stationary contacts. The cutting component includes a piston, which is connected to the moving contact, and the high-temperature and high-pressure gas generated by the gas generator pushes the piston to move.

[0013] Furthermore, the electrical connection structure includes a conductive copper bar. The cutting component includes a piston, and the high-temperature and high-pressure gas generated by the gas generator pushes the piston to move to cut off the conductive copper bar.

[0014] Furthermore, a second circuit is formed between the gas generator and the trigger unit. The second circuit is used to transmit the status signal of the gas generator, and when the magnetic attraction of the static yoke is less than a preset value, the on-off switch closes the second circuit.

[0015] Furthermore, the status signal is a current signal.

[0016] In a second aspect, the present invention also provides an automobile that applies the aforementioned high-voltage electrical circuit safety protection system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system status diagram when the trigger unit in the first embodiment of the present invention is not triggered;

[0018] Figure 2 It is a system status diagram when the trigger unit in the first embodiment of the present invention is triggered;

[0019] Figure 3 It is a system status diagram when the trigger unit in the second embodiment of the present invention is not triggered;

[0020] Figure 4 It is a system status diagram when the trigger unit in the second embodiment of the present invention is triggered;

[0021] MAIN ELEMENT SYMBOL DESCRIPTION:

[0022] Trigger unit 100, pyrotechnic power-off switch 200, housing 210, electrical connection structure 220, moving contact 221, stationary contact 222, gas generator 230, cutting component 240, magnetic control switch 300, switch component 310, on-off switch 311, moving yoke 312, coupling component 320, break interface 321, first circuit 400, wire 500, air gap 600, second circuit 700;

[0023] The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. SPECIFIC EMBODIMENTS

[0024] To facilitate the understanding of the present utility model, the present utility model will be described more comprehensively below with reference to the relevant drawings. Several embodiments of the present utility model are given in the drawings. However, the present utility model can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present utility model more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present utility model belongs. The terms used in the description of the present utility model herein are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0026] The automotive high-voltage electrical circuit mainly consists of components such as a high-voltage battery, a drive motor, a controller, and related high-voltage power distribution devices. When an overload or a short circuit occurs in the circuit, in order to avoid electrical safety accidents and endanger the safety of the vehicle and the occupants, relevant measures must be taken to quickly and automatically cut off the circuit. Aiming at the problems of large delay and low reliability in the triggering and cutting-off process in the existing technology, the present utility model provides a high-voltage electrical circuit safety protection system that quickly and reliably cuts off the automotive high-voltage electrical circuit by triggering a pyrotechnic power-off switch.

[0027] Please refer to Figures 1 to 4 , a high-voltage electrical circuit safety protection system provided by the present utility model. The system includes a triggering unit 100, a pyrotechnic power-off switch 200, and a magnetic control switch 300. The triggering unit 100 is used to generate a continuous triggering electrical signal. The triggering unit 100 can be a separate circuit module or a functional unit integrated in the BMS. The pyrotechnic power-off switch 200 includes a housing 210 and an electrical connection structure 220, a gas generator 230, and a cutting component 240 disposed inside the housing 210. The electrical connection structure 220 is connected in series in the high-voltage electrical circuit. A first circuit 400 for conducting the triggering electrical signal is formed between the gas generator 230 and the triggering unit 100.

[0028] When the first circuit 400 is turned on, the triggering electrical signal generated by the triggering unit 100 is conducted to the gas generator 230 through the first circuit 400. After the electrical pins of the gas generator 230 receive the triggering electrical signal, an explosion occurs to generate high-temperature and high-pressure gas. Then, the high-temperature and high-pressure gas pushes the cutting component to move in the corresponding space area inside the housing 210, causing the connection between the electrical connection structure 220 and the high-voltage electrical circuit to be disconnected. At this time, the high-voltage electrical circuit is in an open state.

[0029] The magnetron switch 300 includes a switch component 310 and a coupling component 320. The switch component 310 is connected in series in the first loop 400, and the on / off state of the first loop 400 can be controlled through the switch component 310. The coupling component 320 is arranged on the wire 500 of the high-voltage electrical loop. The switch component 310 and the coupling component 320 together form a closed magnetic circuit, and an air gap 600 is provided in the closed magnetic circuit. The switch component 310 can move relative to the coupling component 320. Since the energized wire 500 will generate a magnetic field around it, the magnetic field is coupled with the closed magnetic circuit, so that the magnetic force lines of the magnetic field are transmitted along the path direction of the closed magnetic circuit. Since the closed magnetic circuit is provided with an air gap 600, the switch component 310 and the coupling component 320 will each be magnetized by the magnetic field and form north and south poles, thus generating a magnetic attraction force between the two.

[0030] When the current in the high-voltage electrical loop is at a normal value, the intensity of the magnetic field generated by the normal-sized current is relatively small, resulting in the magnetic attraction force between the switch component 310 and the coupling component 320 being insufficient to make the switch component 310 approach the coupling component 320 side. At this time, the first loop 400 is in an open state. When the high-voltage electrical loop is overloaded or a line short circuit occurs, the current flowing through the wire 500 will increase rapidly from the normal value, and the intensity of the magnetic field generated by the current will also increase accordingly. As a result, the magnetic attraction force between the switch component 310 and the coupling component 320 increases. At this time, the switch component 310 approaches the coupling component 320 side under the action of the magnetic attraction force, so that the first loop 400 is in a conducting state, and at the same time the air gap 600 is shortened. When the current in the high-voltage electrical loop returns to the normal value, the switch component 310 can overcome the magnetic attraction force and move away from the coupling component 320, so that the first loop 400 changes from the conducting state to the open state.

[0031] In some alternative embodiments, such as Figures 1 to 4As shown, the coupling component 320 is a static magnetic yoke, and the switching component 310 includes a make-and-break switch 311 and a moving magnetic yoke 312. The static magnetic yoke is arranged around the circumferential side of the wire 500, and a break interface 321 is provided on the static magnetic yoke. The make-and-break switch 311 is connected in series in the first loop 400. That is, in the normal state, the make-and-break switch 311 is in the open state, and thus the first loop 400 is also in the open state. Specifically, the make-and-break switch 311 is a normally open reset switch. Only when an external force is applied and this force can overcome the reset force inherent in the make-and-break switch 311 can it be changed to the closed state, thereby conducting the first loop 400. When the external force is withdrawn, under the action of the reset force of the switch, the make-and-break switch 311 returns to the open state again. The moving magnetic yoke 312 is linked with the make-and-break switch 311, that is, their states change synchronously. As long as the state of one of them changes, the other will also change its state accordingly. The moving magnetic yoke 312 is arranged close to the break interface 321, so that a closed magnetic circuit can be formed between the static magnetic yoke and the moving magnetic yoke 312 to transmit the circular magnetic field generated by the wire 500. If the break interface 321 is not provided, then the circular magnetic field will only be transmitted within the path where the contour shape of the static magnetic yoke is closed and will not enter the moving magnetic yoke 312 and be transmitted in the moving magnetic yoke 312. In addition, the distance between the moving magnetic yoke 312 and the break interface 321 should be set accordingly according to the intensity of the circular magnetic field generated by the current when the high-voltage electrical circuit is overloaded or the line is short-circuited, so as to prevent the magnetic suction force between the static magnetic yoke and the moving magnetic yoke 312 from being too small due to an excessive air gap, and further prevent the moving magnetic yoke 312 from being unable to overcome the reset force of the make-and-break switch 311 and approach the static magnetic yoke.

[0032] During specific operation, when the current in the high-voltage electrical circuit is at the normal value, the intensity of the magnetic field generated by the corresponding normal-sized current is small, the reset force of the make-and-break switch 311 is greater than the magnetic attraction force of the static magnetic yoke on the moving magnetic yoke 312. At this time, the moving magnetic yoke 312 is far from the break interface 321, and the make-and-break switch 311 is in the open state. When the high-voltage electrical circuit is overloaded or the line is short-circuited, the current flowing through the wire 500 will increase rapidly from the normal value, and the intensity of the magnetic field generated by the current will also increase. The reset force of the make-and-break switch 311 is less than the magnetic attraction force of the static magnetic yoke on the moving magnetic yoke 312. At this time, the moving magnetic yoke 312 approaches the break interface 321 and drives the make-and-break switch 311 to move together until the make-and-break switch 311 is closed.

[0033] In this embodiment, since both the coupling component and the main body component of the switch component 310 are mechanical components, the risk of false triggering can be reduced compared to the sensors and BMS used in the prior art. In addition, the preset value can be set by adjusting measures such as the size of the air gap 600 and the reset force of the on-off switch 311, so that different performance high-voltage electrical circuits can be applied. It should be noted that the static yoke and the moving yoke 312 can be made of soft iron or soft magnetic alloy with a relatively high magnetic permeability, and the contour shape of the static yoke is not limited to the U shape in the drawings. For example, it can be a C shape or an asymmetrical shape on the upper and lower sides. Of course, the specific shape to be set depends on the specific situation. Among them, the contour shape of the wire 500 surrounded by the static yoke can also be considered to avoid interference. In addition, when the high-voltage electrical circuit is overloaded or the line is short-circuited, the moving yoke 312 approaches the disconnection interface 321. It can be that the moving yoke 312 contacts the static yoke, or there is a gap between the moving yoke 312 and the static yoke.

[0034] In some alternative embodiments, the trigger electrical signal is a voltage signal, that is, a certain magnitude of voltage, such as 12V DC voltage or 5V DC voltage, is applied to two electrical pins of the gas generator 230 through the first circuit 400.

[0035] In some alternative embodiments, the static yoke and the wire 500 are insulated to prevent the high voltage on the wire 500 from damaging the static yoke. Exemplarily, an insulating layer can be provided between the static yoke and the wire 500, or an insulating shell can be sleeved on the wire 500 and / or the static yoke.

[0036] In some alternative embodiments, as Figure 1 、 Figure 2 shown, the electrical connection structure 220 includes a moving contact 221 and relatively separated static contacts 222. The cutting component 240 is a piston, and the piston is connected to the moving contact 221. When the current in the high-voltage electrical circuit is normal, the first circuit 400 is disconnected. At this time, the moving contact 221 connects the two relatively separated static contacts 222, and the high-voltage electrical circuit is in a conducting state. When the high-voltage electrical circuit is overloaded or the line is short-circuited, the first circuit 400 is conducted, and the trigger electrical signal generated by the trigger unit 100 is conducted to the gas generator 230 through the first circuit 400. The gas generator 230 explodes to generate high-temperature and high-pressure gas, and the high-temperature and high-pressure gas pushes the piston to move, thereby separating the connection between the moving contact 221 and the two static contacts 222. At this time, the high-voltage electrical circuit is in a disconnected state.

[0037] In some alternative embodiments, as Figure 3 、 Figure 4As shown, the electrical connection structure 220 is a conductive copper bar, and the cutting component 240 is a piston. When the current in the high-voltage electrical circuit is at a normal value, the first circuit 400 is disconnected. At this time, the conductive copper bar is connected in series in the high-voltage electrical circuit, and the high-voltage electrical circuit is in a conducting state; when an overload or a short circuit occurs in the high-voltage electrical circuit, the first circuit 400 is conducted, and the triggering signal generated by the triggering unit 100 is conducted to the gas generator 230 through the first circuit 400. The gas generator 230 explodes to generate high-temperature and high-pressure gas, and the high-temperature and high-pressure gas pushes the piston to move, thereby cutting off the conductive copper bar. At this time, the high-voltage electrical circuit is in an open state.

[0038] In some alternative embodiments, as Figures 1 to 4 shown, a second circuit 700 is formed between the gas generator 230 and the triggering unit 100. The second circuit 700 is used to transmit the status signal of the gas generator 230. When the magnetic attraction of the static magnetic yoke is less than a preset value, the on-off switch 311 closes the second circuit 700, so that the conduction status of the gas generator 230 can be monitored in real time, so as to prevent the gas generator 230 from failing without being detected, thereby improving the reliability of the system. Preferably, in this embodiment, the on-off switch 311 is a two-way switch. When the magnetic attraction of the static magnetic yoke is less than the preset value, the two-way switch closes one of its contacts to conduct the second circuit 700. At this time, the first circuit 400 is in an open state, and when the magnetic attraction of the static magnetic yoke is greater than the preset value, the two-way switch closes the other contact to conduct the first circuit 400. At this time, the second circuit 700 is in an open state.

[0039] In some alternative embodiments, the status signal is a current signal. Specifically, during implementation, the current value conducted in the second circuit 700 can be controlled at a relatively low current level, such as 100 mA.

[0040] In a second aspect, the present invention further provides an automobile that applies the foregoing high-voltage electrical circuit safety protection system.

[0041] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0042] The above-described embodiments merely represent several implementation manners of the present utility model. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the protection scope of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the present utility model shall be subject to the appended claims.

Claims

1. A high-voltage electrical circuit safety protection system, characterized in that include: A trigger unit, used for generating a continuous trigger electrical signal; A pyrotechnic power-off switch, comprising a housing and an electrical connection structure, a gas generator, and a cut-off assembly arranged in the housing, wherein the electrical connection structure is connected in series in a high-voltage electrical circuit, a first circuit for conducting the trigger electrical signal is formed between the gas generator and the trigger unit, and when the first circuit is turned on, the gas generator generates high-temperature and high-pressure gas to push the cut-off assembly to disconnect the electrical connection structure from the high-voltage electrical circuit; A magnetically controlled switch, comprising a switch component and a coupling component, wherein the switch component is connected in series in the first circuit, the coupling component is arranged on the conductor of the high-voltage electrical circuit, the switch component and the coupling component together form a closed magnetic circuit for transmitting the magnetic lines of force generated by the conductor, and the closed magnetic circuit is provided with an air gap; the switch component can move relative to the coupling component to shorten the air gap and conduct the first circuit when the intensity of the magnetic lines of force in the closed magnetic circuit exceeds a preset value, and to expand the air gap and disconnect the first circuit when the intensity of the magnetic lines of force in the closed magnetic circuit is lower than the preset value.

2. The high-voltage electrical circuit safety protection system according to claim 1, characterized in that The coupling component includes a static magnetic yoke, and the switch component includes an on-off switch and a moving magnetic yoke. The static magnetic yoke is arranged around the circumference of the conductor and is provided with a disconnection interface. The on-off switch is connected in series in the first circuit. The moving magnetic yoke is operatively arranged in conjunction with the on-off switch, and the moving magnetic yoke is arranged close to the disconnection interface to form the closed magnetic circuit between the static magnetic yoke and the moving magnetic yoke. When the magnetic attraction of the static magnetic yoke is greater than a preset value, the moving magnetic yoke moves away from the disconnect interface, and the on-off switch closes the first circuit; and when the magnetic attraction of the static magnetic yoke is less than a preset value, the moving magnetic yoke approaches the disconnect interface, and the on-off switch disconnects the first circuit.

3. The high-voltage electrical circuit safety protection system according to claim 1, characterized in that, The trigger electrical signal is a voltage signal.

4. The high-voltage electrical circuit safety protection system according to claim 2, characterized in that, The static magneto yoke is insulated from the conducting wire.

5. The high-voltage electrical circuit safety protection system according to claim 1, wherein The electrical connection structure includes a moving contact and relatively spaced static contacts. The cut-off assembly includes a piston connected to the moving contact. The high-temperature and high-pressure gas generated by the gas generator pushes the piston to move.

6. The high-voltage electrical circuit safety protection system according to claim 1, characterized in that, The electrical connection structure includes a conductive copper bar, and the cutting assembly includes a piston. The high-temperature and high-pressure gas generated by the gas generator pushes the piston to move so as to cut off the conductive copper bar.

7. The high-voltage electrical circuit safety protection system according to claim 2 or 4, characterized in that, A second circuit is formed between the gas generator and the trigger unit, and the second circuit is used to transmit a status signal of the gas generator. When the magnetic attraction force of the static magnetic yoke is less than a preset value, the on / off switch closes the second circuit.

8. The high-voltage electrical circuit safety protection system according to claim 7, wherein, The state signal is a current signal.

9. A vehicle, characterized in that, A high-voltage electrical circuit safety protection system as described in any one of claims 1 to 8 is applied.

Images