CN115036193A

CN115036193A - High-reliability active and passive integrated protection device

Info

Publication number: CN115036193A
Application number: CN202210713184.0A
Authority: CN
Inventors: 石晓光; 王立强; 姜依玲
Original assignee: Xian Zhongrong Electric Co Ltd
Current assignee: Xian Zhongrong Electric Co Ltd
Priority date: 2022-03-22
Filing date: 2022-06-22
Publication date: 2022-09-09
Also published as: WO2023179160A1; CN217788320U

Abstract

The invention relates to the field of electric control and electric automobiles, and discloses a high-reliability active and passive integrated protection device, which comprises a first conductor, a first melt, a second conductor and a first excitation device, wherein the first conductor, the first melt, the second conductor and the first excitation device are sequentially connected in series; the first melt is connected with a first trigger circuit in parallel; under the normal working state of the first melt, the first trigger circuit is not conducted with the first excitation device; when the first melt is fused, the first melt is disconnected with the circuit, or the first melt can be driven to be in conductive connection with a signal receiving end of the first excitation device under the action of arc energy or elasticity so as to send a trigger signal to the first excitation device; the first excitation means breaks the first conductor in response to receiving the trigger signal. The first excitation device is used as the standby protection of the first melt, so that the working reliability of the protection device is improved.

Description

High-reliability active and passive integrated protection device

Technical Field

The invention relates to the field of power control and electric automobiles, in particular to a protection device for circuit protection.

Background

The existing circuit protection device is mechanically disconnected, most of the existing circuit protection devices trigger an excitation source to act through an external trigger signal, and the circuit is disconnected through a mechanical mode. Comprising an excitation source, a shut-off device and a conductor through which a current flows. The excitation source receives an external trigger signal, ignites to release high-pressure gas, and drives the cutting device to act to cut off the conductor.

In another method, a trigger signal generated by the protection device triggers the excitation source to act, and the circuit is disconnected mechanically. The difference between the trigger by the external trigger signal is that a trigger circuit for collecting the internal trigger signal is added. This type of protection device can carry high voltages and high currents.

Both of these protection devices have certain disadvantages. When the external trigger signal circuit or its own trigger circuit malfunctions or the excitation source fails, there is a possibility that a serious safety accident may occur because the current is not mechanically cut off. Therefore, the reliability of both products is unstable.

Disclosure of Invention

The invention aims to provide an active and passive integrated protection device, which is characterized in that a first melt is connected in series in a conductor, and when the first melt is fused and does not sustain an arc, a circuit is directly disconnected through fusing; when arc holding is generated, the arc voltage is used for driving the trigger circuit to be connected with the excitation source, a trigger signal is provided for the excitation source, and the circuit is disconnected in a mechanical mode through the action of the excitation source. The protection device of the invention breaks the circuit by fusing and combining with a mechanical breaking mode, thereby adding the guarantee of a double breaking circuit and improving the reliability of the protection device.

In order to achieve the purpose, the technical scheme provided by the invention is a high-reliability active and passive integrated protection device, which comprises a first conductor, a first melt, a second conductor and a first excitation device, wherein the first conductor, the first melt and the second conductor are sequentially connected in series; the first melt is connected with a first trigger circuit in parallel; under the normal working state of the first melt, the first trigger circuit is not conducted with the first excitation device;

when the first melt is fused, the first melt is disconnected with the circuit, or the first melt can be driven to be in conductive connection with a signal receiving end of the first excitation device under the action of arc energy or elasticity so as to send a trigger signal to the first excitation device; the first excitation means opens the first conductor in response to receiving a trigger signal.

Preferably, the signal receiving end of the first excitation device is electrically connected with an external signal trigger circuit to transmit a trigger signal for the first excitation device.

Preferably, when the first melt is in an arc state after being melted, the signal receiving end of the first excitation device is driven to be disconnected from the external signal trigger circuit, and then the first excitation device is provided with a trigger signal by being electrically connected with the first trigger circuit.

Preferably, a third trigger circuit is connected in parallel with the first melt, and the third trigger circuit is electrically connected with the first excitation device; when the first melt normally works, the third trigger circuit does not send a trigger signal to the first excitation device, and when the first melt is fused, the third trigger circuit sends a trigger signal to the first excitation device.

Preferably, the device further comprises a second excitation device, and the second excitation device receives a trigger signal to act to disconnect the first conductor; the first melt is also connected with a second trigger circuit in parallel, and the second trigger circuit is in conductive connection with a signal receiving end of a second excitation device; when the first melt works normally, the second trigger circuit does not send a trigger signal to the second excitation device; when the first melt melts, the second trigger circuit sends a trigger signal to the second excitation device.

Preferably, the second excitation device comprises a second excitation source and a second cutting device, the first melt penetrates through the first melt shell, when the first melt is fused, the second trigger circuit is conducted to send an excitation signal to the second excitation source, the second excitation source acts to drive the second cutting device to displace, and the first melt shell is driven to drive the first melt to integrally displace and separate from the first conductor and the second conductor.

Preferably, the device is further provided with a transmission device, a first switch device is arranged at one end of a lead of the first trigger circuit or the first excitation device, when the first melt melts, the transmission device can be driven to act under the action of arc energy or elastic force, and the transmission device drives the first switch device to act, so that the first trigger circuit is electrically connected with the signal receiving end of the first excitation device to provide a trigger signal for the first excitation device.

Preferably, a first switch device is conductively connected to a signal receiving end of the first excitation device, and the first excitation device is conductively connected to the external trigger signal circuit through the first switch device; when the first melt is fused, the transmission device is driven to act under the action of arc energy or elasticity, and the transmission device drives the first switch device to act to disconnect the first excitation device from the external trigger signal circuit, so that the first trigger circuit is electrically connected with a lead of the first excitation device through the first switch device.

Preferably, the first switch device is two conductive connecting pieces, and two ends of each conductive connecting piece are respectively in conductive connection with the external trigger signal circuit and the signal receiving end of the first excitation device through wires; when the first melt is fused, the electric arc energy generated by the first melt drives the transmission device to act, and after the transmission device disconnects the conductive connecting piece, the conductive connecting piece part which is conductively connected with the first exciting device is driven to be conductively connected with the first trigger circuit.

Preferably, the first melt is connected in parallel with the second melt; the transmission comprises a spring and piston structure; the second melt restrains the spring in a compressed state; when the first melt is fused, the second melt is fused, the piston structure acts under the action of elasticity, and the first trigger circuit is driven to be in conductive connection with the signal receiving end of the first excitation device so as to provide a trigger signal for the first excitation device.

Preferably, the first melt or the second melt is located in a cavity, the transmission means closing said cavity.

Preferably, the transmission device is a flexible film enclosing the first melt or the second melt; or the transmission device is of a piston structure.

Preferably, the cavity in which the first melt or the second melt is located is filled with an arc-extinguishing medium.

Preferably, the first trigger circuit comprises a transformer, the transformer high-voltage end circuit is connected with the first melt in parallel, and the transformer low-voltage end circuit is not conducted with the first excitation device; when the first melt works normally, the low-voltage circuit of the transformer is not conducted with the first excitation device; when the first melt melts, the arc energy generated by the melting of the first melt can drive the low-voltage end circuit of the transformer to be electrically connected with the signal receiving end of the first excitation device, and the first trigger circuit sends a trigger signal to the first excitation device.

Preferably, a conduction detection device for controlling the on-off of the circuit is connected in series with the high-voltage circuit of the transformer.

Preferably, the conduction detection device is an active or passive device.

According to the high-reliability active and passive integrated protection device, in a normal state, the first trigger circuit is not conducted, and the first excitation device is not communicated with the first trigger circuit; the current flows through the first conductor and the first melt for current detection. When the first melt is fused and the fused part is not in an arc state, the circuit is disconnected, and the first trigger circuit and the first excitation device do not act; when the first melt melts and the melting part keeps an arc, the arc energy generated by melting drives the first trigger circuit to be communicated with the first excitation device, the voltage signal at the first melt is used as a trigger signal to be sent to the first excitation device, and the first excitation device acts to mechanically disconnect the first conductor and the circuit.

The first excitation device is connected with an external trigger signal, and the external trigger signal is used for providing a trigger signal for the first excitation device; when the first melt melts and the first exciting device does not act to cut off the first conductor breaking circuit, the first melt melts and the arc is maintained at the melting position, the first trigger circuit is driven to be conducted with the first exciting device through the arc energy generated by the melting of the first melt to provide a trigger signal for the first exciting device, and the first exciting device acts to mechanically break the circuit. The double protection is realized by adding an external trigger circuit to provide an external trigger signal and a self-excitation signal generated by fusing the first melt.

By adding the second trigger circuit and the second excitation device, on the basis of the first excitation device and the first melt, a circuit disconnection guarantee is added, the circuit can be disconnected by the protection device, and the safety and reliability of the protection device are ensured.

The protection device can actively disconnect the circuit, and can also passively disconnect the circuit when a fault occurs. Through multiple protection, the reliability of the protection device is improved, and the protection device is suitable for various application scenes such as low voltage, high voltage and the like.

Drawings

Fig. 1 is a schematic circuit diagram of the first switch of embodiment 1 connected to the first excitation means.

Fig. 2 is a schematic circuit diagram illustrating the first trigger circuit connected to the first excitation device after the operation of fig. 1.

Fig. 3 is a schematic circuit diagram of the first switch connected to the first trigger circuit in embodiment 1.

Fig. 4 is a schematic circuit diagram of the first switch of embodiment 2 connected to the first flip-flop circuit.

Fig. 5 is a schematic circuit diagram of embodiment 3 with an external trigger circuit added.

Fig. 6 is a schematic circuit diagram of the first trigger circuit including a transformer in embodiment 3.

FIG. 7 is a schematic circuit diagram of embodiment 3 after the first fuse element of FIG. 6 is fused.

FIG. 8 is a schematic circuit diagram in the normal operation of embodiment 4.

FIG. 9 is a schematic circuit diagram of embodiment 5 with the addition of a second trigger circuit and a second excitation means.

Fig. 10 is a schematic diagram of the circuit of fig. 9 after the first melt is melted.

Fig. 11 is a schematic circuit diagram of the second excitation means provided on the second conductor according to embodiment 6.

FIG. 12 is a schematic structural view of the external appearance of a transmission device according to embodiment 7.

Fig. 13 is a schematic cross-sectional view of the transmission of fig. 12.

Fig. 14 is a schematic view of the sectional structure a-a of fig. 13.

FIG. 15 is a schematic circuit diagram of example 8 with a second melt in parallel.

Fig. 16 is a schematic view of the transmission of fig. 15.

Fig. 17 is a schematic structural view of the second actuator of fig. 15.

Wherein: the fuse element comprises a first conductor 10, a first melt body 20, a second conductor 30, a second melt body 100, a first excitation device 40, a first excitation source 401, a first lead 4011, a second lead 4012, an external trigger circuit 450, a one-way conduction device 4501, a first switch 50, a first trigger circuit 60, a third lead 601, a fourth lead 602, a transformer 603, a rectifier bridge 604, a conduction detection device 605, a transmission device 70, a piston structure 701, an arc extinguishing chamber 702, a bump 703, a wiring slot 704, a spring 705, an insulating bottom cover 706, a second excitation device 80, a second excitation source 801, a second cut-off device 802, a second trigger circuit 90 and a conduction detection device 901.

Detailed Description

The structural orientation terms such as up, down, left, right, front, rear, top, bottom, etc. referred to in the specification do not limit the structural position, but merely facilitate understanding.

In view of the above technical solutions, preferred embodiments are described in detail with reference to the drawings.

Example 1

Referring to fig. 1, a high-reliability active and passive integrated protection device comprises a first conductor 10, a first fuse element 20 and a second conductor 30 which are connected in series in sequence, wherein current flows through the first conductor 10, the first fuse element 20 and the second conductor 30. The requirement of the first fuse element 20 is that it will melt in the event of a small fault current, breaking the circuit through the first conductor, the first fuse element and the second conductor.

The first excitation means 40 is disposed on the first conductor 10 side, and a breaking weak point 101 may be provided on the first conductor 10 at the first excitation means 40 as needed to reduce the mechanical strength. When the first actuator 40 receives the trigger signal, the first actuator 40 acts on the trigger signal to sever the first conductor 10 from the break weakness.

The first excitation means 40 comprises a first excitation source 401, first cut-off means. A first excitation source and a first cut-off device are arranged in the housing through which the first conductor 10 passes. The structure between the first excitation source and the first cutting device meets the condition that after the first excitation source receives the trigger signal, the released driving force can drive the first cutting device to displace to cut off the first conductor breaking circuit.

The first excitation source 401 adopts a gas generating device, a signal receiving end of the first excitation source 401 is respectively connected with a first conducting wire 4011 and a second conducting wire 4012, and free ends of the first conducting wire 4011 and the second conducting wire 4012 are conductively connected with a first switch 50.

The first excitation source 401 heats up and then ignites upon receiving the trigger signal, releasing high pressure gas. The first cutting device is driven by the high-pressure gas to act, so that the first conductor 10 is cut off and the circuit is broken.

The first fuse element 20 is connected in parallel with a first trigger circuit 60, the first trigger circuit is connected with one end of the first fuse element 20 through a third conducting wire 601 and a fourth conducting wire 602 respectively, and the third conducting wire 601 and the fourth conducting wire 602 are not connected. The first trigger circuit 60 collects a voltage signal at the first melt 20 as a trigger signal; when the first fuse element is in a normal working state, the first trigger circuit is not conducted because the third conductor 601 and the fourth conducting wire 602 are not connected; the first trigger circuit is also not connected to the first switch 50 wired to the first excitation source 401.

The first excitation source is a gas generating device which ignites according to the received trigger signal and then releases high-pressure gas to generate driving force. In the following examples, the excitation source was the same as in example 1.

The working principle is as follows:

in normal operation, current flows through the first melt 20, and the voltage across the first melt 20 is small. When the fault current is low, an arc generated at the fusing position of the first fuse-element 20 is very small, the arc is quickly extinguished through air or an arc extinguishing medium arranged at the fusing position of the first fuse-element, and the circuit of the current flowing through the first fuse-element is disconnected through the fusing of the first fuse-element. In this case, since the arc is small and rapidly extinguished, and the energy of the arc is also small, the first switch 50 cannot be driven to be electrically connected with the first trigger circuit, so as to turn on the first trigger circuit, and therefore, neither the first trigger circuit nor the first excitation device is activated.

When the fault current is relatively large, the arc generated when the first melt 20 melts cannot be extinguished quickly, and a sustained arc is formed at the position where the first melt melts, under the energy of the arc, the first switch 50 is driven to displace and be connected with the third lead and the fourth lead of the first trigger circuit 60, so that the first trigger circuit is connected with the first excitation device, referring to fig. 2, the first trigger circuit sends the voltage at two ends of the first melt as a trigger signal to the first excitation source of the first excitation device, and the first excitation source acts to drive the first cut-off switch to mechanically cut off the first conductor 10 to form a fracture, so that the cut-off current flows through the first conductor, the second conductor and the circuit of the first melt.

When the arc energy drives the first switch 50 to displace, the transmission device 70 is disposed between the first melt and the first switch 50, and referring to fig. 8 to 11, the transmission device can well isolate the arc energy from surrounding the first melt, so as to prevent the arc energy from dissipating and damaging other components or devices.

The conducting device can be formed by wrapping the first melt by a flexible film, and the flexible film is made of an insulating material. An arc extinguishing medium is filled between the flexible film and the first melt. When the first melt melts, the generated arc energy drives the flexible film to stretch, the first switch 50 is disconnected through the flexible film, then one end connected with the first excitation source is driven to move towards one end of a lead of the first trigger circuit and is in conductive connection with the first trigger circuit, the connection between the first excitation source and the first trigger circuit is connected, and the first trigger circuit sends voltage signals at two ends of the first melt as trigger signals to the first excitation source to enable the first excitation source to work.

The transmission device can be a piston structure, the first melt is placed in a cavity, the arc extinguishing medium is filled in the cavity, and the piston structure closes the cavity. The piston structure is made of insulating materials. When the first melt melts, the generated arc energy drives the piston structure to displace, the first switch 50 is disconnected through the piston structure, then one end connected with the first excitation source is driven to displace towards one end of a lead of the first trigger circuit and is in conductive connection with the first trigger circuit, the connection between the first excitation source and the first trigger circuit is connected, and the first trigger circuit sends voltage signals at two ends of the first melt as trigger signals to the first excitation source to enable the first excitation source to work.

The transmission may also be hydraulically driven.

The first switch 50 may also be connected to one end of the first trigger circuit, see fig. 3, and its structure and operation principle are the same as those connected to the first excitation device.

In the example, under the condition that the first fuse element is fused to break the circuit and the circuit cannot be broken when the first fuse element is fused, the first trigger circuit is driven to be connected with the first excitation device through the arc energy generated when the first fuse element is fused, the trigger signal is provided for the first excitation device, and the first conductor breaking circuit is broken. In this embodiment, the double protection is adopted, and the working reliability of the protection device is improved.

Example 2

The difference from embodiment 1 is that an external trigger circuit 450 is added. Referring to fig. 4, the first switch 50 is connected to the first trigger circuit 60. The first driver source 401 of the first driver device 40 is electrically conductively connected to the external trigger circuit 450 via a first line 4011 and a second line 4012.

The first excitation means 40 is provided with an activation signal by an external activation circuit 450, which opens the first conductor 10 and breaks the circuit.

The first fuse element 20 is connected in parallel with a first trigger circuit 60, the first trigger circuit 60 is connected to two ends of the first fuse element 20 through a third conducting wire 601 and a fourth conducting wire 602, and the third conductor 601 and the fourth conducting wire 602 are not connected. The first switch 50 is conductively connected to one end of the third conductor 601 and the fourth wire 602. The current flows through the first conductor 10, the first melt 20 and the second conductor 30

An actuator 70 is disposed between the first melt 20 and the first switch 50.

Under normal operating conditions, current flows through the first conductor 10, the first melt 20, and the second conductor 30. The external trigger circuit 450 is not operated and the first actuator 40 is not operated.

When the external trigger circuit 450 is activated, the external trigger circuit 450 provides a trigger signal to the first actuator, which is activated to cut the first conductor 10 upon receipt of the trigger signal. The external trigger circuit 450 is determined according to an external control condition, i.e., a control system of the client. The external control condition may be zero current, a trigger signal sent under a specific condition, or a threshold value set, and when the indicator exceeds the threshold value, the external trigger circuit 450 is controlled to act to provide a trigger signal to the first excitation device to trigger the first excitation device to act to disconnect the first conductor 10.

When the fault current occurs, the external trigger circuit 450 does not send a trigger signal to the first excitation source, the first fuse body 20 is fused, and if the fused part of the first fuse body 20 does not have arc holding, the first fuse body 20 is fused to disconnect the circuit;

if the first fused mass 20 is fused to form an arc, the accumulated arc energy drives the transmission device to drive the first switch 50 on the first trigger circuit 60 to displace and electrically connect with the first excitation source signal receiving end of the first excitation device, so that the first trigger circuit is conducted with the first excitation source to send a trigger signal to the first excitation source 401, and the first cut-off device acts to cut off the first conductor 10 to break the circuit.

Since the first switch 50 of the first trigger circuit 60 is driven to communicate with the signal receiving end of the first excitation device 40 and also communicate with the external trigger circuit 450, in order to prevent the high voltage at the two ends of the break of the first melt 20 from affecting the external trigger circuit 045, a unidirectional conducting component, such as a diode, is disposed in the external trigger circuit 450 to prevent the current from flowing from the inside of the protection device to the external trigger circuit.

Example 3

The improvement is carried out on the basis of the embodiment 2. Referring to fig. 5, a first melt 20 is connected in series between a first conductor 10 and a second conductor 30.

The first actuating device 40 is electrically conductively connected to the external triggering circuit 450 via a first switch 50. The external trigger circuit 450 is conventional and will not be described herein.

The first fuse element 20 is connected in parallel with the first trigger circuit 60, the first trigger circuit 60 is connected to two ends of the first fuse element 20 through a third conducting wire 601 and a fourth conducting wire 602, and the third conducting wire 601 and the fourth conducting wire 602 are not connected. The first trigger circuit 60 is not connected to the first excitation device 40 or the external trigger circuit 450.

Current flows through the first conductor 10, the first melt 20, and the second conductor 30.

The first excitation means is provided with a trigger signal by an external trigger circuit 450 and is operated to cut the first conductor 10 upon receipt of the trigger signal. The external trigger circuit 450 is determined according to an external control condition, i.e., a control system of the client. The external control condition may be zero current, a trigger signal sent under a specific condition, or a threshold value set, and when the indicator exceeds the threshold value, the external trigger circuit 450 is controlled to act to provide a trigger signal to the first excitation device to trigger the first excitation device to act to disconnect the first conductor 10.

When the first fusant 20 is fused and no arc holding is generated, the first fusant 20 breaks a circuit;

when the first fuse element 20 melts, arc energy generated by arc-holding is generated to drive the transmission device 70 to act, the transmission device 70 is displaced to drive the first switch 50 to disconnect the first excitation device 40 from the external trigger circuit 450, and then the first switch 50 is driven to be in conductive connection with the first trigger circuit 60, so that the first trigger circuit is in conductive connection with the first excitation device to provide a trigger signal for the first excitation device.

For the purpose of operational reliability, various components or circuits that improve operational reliability may be conductively connected to the third conductor and the fourth conductor of the first trigger circuit.

Fig. 6 is a specific circuit diagram of fig. 5, in which a third conductive wire 601 and a fourth conductive wire 602 connected to two ends of the first fuse element 20 are electrically connected to a high-voltage end circuit 6031 of a transformer 603, so that the high-voltage end circuit of the transformer is connected in parallel with the first fuse element 20, and the low-voltage end circuit 6032 of the transformer is not connected to the first excitation source 401 of the first excitation device 40. A rectifier bridge 604 is connected in series in the low-voltage circuit.

The signal receiving end of the first excitation source 401 of the first excitation device 40 is connected to the first switch 50 through the first conducting wire 4011 and the second conducting wire 4012, respectively, and the external trigger circuit 450 is electrically connected to the first excitation source 401 through the first switch 50.

The working principle is as follows:

under normal operation, the first trigger circuit 60 is not conducted to the first excitation source. The external trigger circuit 450 does not send a trigger signal to the first excitation source.

When the fault current occurs, the external trigger circuit 450 does not send a trigger signal to the first excitation source, the first fused body 20 is fused, and if the fused part of the first fused body 20 does not have arc holding, the first fused body 20 is fused to disconnect the circuit;

if the first fuse element 20 melts to form an arc, referring to fig. 7, the accumulated arc energy drives the transmission device to disconnect the first switch from the external trigger circuit 450, the first switch 50 is electrically connected to the low-voltage end of the first trigger circuit 60, the first trigger circuit is connected to the first excitation source, a trigger signal is sent to the first excitation source 401, and the first cut-off device is operated to cut off the circuit of the first conductor 10.

In order to further improve the operational reliability, a conduction detection device 605 is connected in series to the high-voltage end of the transformer, and the conduction detection device 605 is not conducted in a normal operating state. The conduction detection device 605 is an active or passive device or a conduction detection circuit capable of realizing on-off control, such as a TVS tube, a MOSFET tube, etc.; the conduction detection circuit capable of realizing on-off control is a conventional circuit technology, and is not described herein again. When the first melt is working normally, the conduction detecting device 605 is not conducted. When the first melt melts, the conduction detection device 605 is turned on.

A unidirectional device is connected in series to the external trigger circuit 450, so that a trigger signal can be sent to the first excitation source 401 only from one end of the external trigger circuit 450.

Example 4

Fig. 8 is a schematic circuit diagram of fig. 5 with a protection added. Referring to fig. 8, the first trigger circuit 60 includes a third conductive line 601 and a fourth conductive line 602 connected in parallel at both ends of the first fuse element 20, and the free ends of the third conductive line 601 and the fourth conductive line 602 are not connected and are not connected to the first excitation source 401. In order to better improve the reliability of the first trigger circuit, various components or circuits can be electrically connected to the third lead and the fourth lead of the first trigger circuit according to requirements.

The external trigger circuit 450 is electrically conductively connected to the first excitation source 401 via the first switch 50. When the first switch 50 is driven by an external force, it can be displaced to be electrically connected with the third conducting wire 601 and the fourth conducting wire 602, so that the first excitation source 401 is electrically connected with the first trigger circuit 60.

A third trigger circuit 60a is also connected in parallel to the first melt 20. The third triggering circuit 60a includes a transformer 60a-1 and a rectifier bridge 60 a-2. The high voltage side of the transformer 60a-1 is connected in parallel with the first melt 20, and the low voltage side is connected to the external trigger circuit 450 and the lead wire connected to the first excitation source 401. The rectifier bridge 60a-2 is connected in series in the low-voltage circuit, and rectifies the transformed trigger signal and transmits the rectified trigger signal to the first excitation source 401. The high voltage and the low voltage of the protection device are isolated through the high voltage end and the low voltage end of the transformer 60a-1, and the safety and the reliability of the device are guaranteed. In a normal operating state, since the voltage at the first melt 20 is very small, and after passing through the transformer, the voltage at the low-voltage end of the transformer is very small and can be almost ignored, in the normal operating state, the third trigger circuit cannot send a trigger signal to the first excitation source, and the first excitation source does not act. The third trigger circuit is not limited to the circuit structure in fig. 8, and the structure of the third trigger circuit only needs to meet the condition that the first fuse is fused, and the third trigger circuit sends a trigger signal to the first excitation source.

Under normal operating conditions, current flows through the first conductor 10, the first melt 20, and the second conductor 30.

Principle of operation

Under normal operation, the first trigger circuit 60 and the first driving source 401 are not conducted. The external trigger circuit 450 and the third trigger circuit do not send a trigger signal to the first excitation source.

When the fault current occurs, the external trigger circuit 450 does not send a trigger signal to the first excitation source, the first fuse element 20 is fused, and if the fused part of the first fuse element 20 does not have arc holding, the first fuse element 20 is fused to break the circuit.

If the arc is maintained at the fusing part of the first melt 20, the voltage at the fusing part of the first melt is suddenly increased, the transformer of the third trigger circuit 60a transforms the high voltage at the fusing part of the first melt into low voltage, the low voltage is rectified and then sent to the first excitation source 401 to serve as a trigger signal, and the first excitation source 401 acts to drive the first cut-off device to cut off the first conductor 10 to cut off the circuit;

if the first fuse element 20 melts, before the circuit is disconnected, the accumulated arc energy drives the transmission device 70 to act, the first switch 50 is disconnected from the external trigger circuit 450, the first switch 50 is electrically connected with the first trigger circuit 60, so that the first trigger circuit 60 is conducted with the first excitation source 401, a voltage signal at the melting part of the first fuse element is sent to the first excitation source 401 as a trigger signal, the first excitation source 401 acts, and the first cutting device acts to cut off the first conductor 10 to break the circuit.

In order to further improve the working reliability, the high-voltage end of the transformer is connected with a conduction detection device 60a-3 in series, and the conduction detection device 60a-3 is not conducted in a normal working state. The conduction detection device 60a-3 is an active or passive device or a conduction detection circuit capable of realizing on-off control, such as a TVS tube, a MOSFET tube, etc.; the conduction detection circuit capable of realizing on-off control is a conventional circuit technology, and is not described herein again. When the first melt is operating normally, the conduction detecting means 60a-3 is not conducted. When the first fuse element melts, the conduction detection device 60a-3 is conducted.

A unidirectional device is connected in series to the external trigger circuit 450, so that a trigger signal can be sent to the first excitation source 401 only from one end of the external trigger circuit 450. In this embodiment, by adding the third trigger circuit, the protection device has one more standby protection to form quadruple protection, and the reliability is better.

The specific circuit structure of the third trigger circuit is not limited to that a transformer and a rectifier bridge are arranged in the circuit, and the third trigger circuit can send a trigger signal after the first melt is fused as long as the third trigger circuit does not send the trigger signal under the normal working state of the first melt.

Example 5

Referring to fig. 9, on the basis of fig. 5, a second excitation device 80 is further disposed on the first conductor 10 side, a second trigger circuit 90 is connected in parallel to the first melt 20, and the second trigger circuit 90 is electrically connected to a second excitation source 801 of the second excitation device 80 through a wire. The second excitation device 80 includes a second excitation source 801 and a second cutting device 802, and the second excitation source operates in response to a received trigger signal transmitted from the second trigger circuit to drive the second cutting device to cut the first conductor 10 and open the circuit.

The first trigger circuit 60 is the same as the first trigger circuit 60 in fig. 5, and the second trigger circuit 90 can be implemented with reference to the structure of the third trigger circuit 60a in fig. 8 in embodiment 4. The second trigger circuit 90 is not limited to the structure of the third trigger circuit 60a in fig. 8, as long as it is satisfied that the trigger signal is not sent to the second excitation device when the first melt is operating normally.

In normal operation, current flows through the first conductor 10, the first melt 20, and the second conductor 30.

The working principle is as follows:

when the first melt normally works, current flows through the first conductor 10, the first melt 20 and the second conductor 30. The first trigger circuit 60 is not connected to the first excitation device 40, the first excitation device does not operate; since the voltage at the first melt is very low, the second trigger circuit does not send a trigger signal to the second excitation device, nor does the second excitation device act.

When the external trigger circuit 450 action condition is met, a trigger signal is provided to the first excitation means 40 by the external trigger circuit 450, and the first excitation means acts to cut the first conductor 10 upon receiving the trigger signal. The external trigger circuit 450 is determined according to an external control condition, i.e., a control system of the client. The external control condition may be that a trigger signal is sent under a specific condition when the current is zero, or a threshold value is set, and when the index exceeds the threshold value, the external trigger circuit 450 is controlled to act to provide a trigger signal to the first excitation device, so as to trigger the first excitation device to act to break the first conductor 10.

If the arc holding is formed at the fusing part of the first melt 20, the voltage at the fusing part of the first melt rises suddenly, the second trigger circuit 90 sends a voltage signal at the fusing part of the first melt to the second excitation source 801 as a trigger signal, and the second excitation source 801 acts to drive the second cut-off device to cut off the first conductor 10 to cut off the circuit;

By adding the second trigger circuit and the second excitation device, when the first melt 20 is fused, the second trigger circuit acts first, a trigger signal is sent to the second excitation device, and the second excitation device acts first. The first trigger circuit and the first excitation device are conducted only when the first switch is driven to act by the arc energy accumulated after the first fuse element 20 is fused, and the first excitation device acts.

In order to further improve the reliability of the second trigger circuit, a conduction detection device 901 is connected in series in the second trigger circuit 90, and the conduction detection device 901 is an active or passive device or a conduction detection circuit capable of realizing on-off control, such as a TVS tube, a MOSFET tube, etc.; the conduction detection circuit capable of realizing on-off control is a conventional circuit technology, and is not described herein again. When the first melt normally works, the conduction detection device 901 is not conducted, and when the first melt is fused, the conduction detection device 901 is conducted.

In the embodiment, two groups of excitation devices and two groups of trigger circuits are combined with an external trigger circuit, so that when one trigger circuit fails or an excitation source fails, the other excitation source can act to cut off the circuit, and the reliability of the product is improved.

The second trigger circuit and the second excitation device in fig. 9 can also be added based on fig. 8, and the second trigger circuit and the second excitation device are added based on fig. 8, so that the formed protection device has five-fold protection.

Example 6

Referring to fig. 11, on the basis of fig. 9, a second excitation device 80 is disposed on the second conductor 30, and the rest of the structure is the same. The first conductor 10 is cut when the first excitation means is operated, and the second conductor 30 is cut when the second excitation means 80 is operated.

The working principle is the same as that of embodiment 5.

Example 7

In the present embodiment, a structure of a transmission is described. Referring to fig. 12 to 14, the transmission device 70 is disposed at the first melt 20, the transmission device 70 includes an insulating housing, a cavity with an open end is disposed in the housing, the first melt 20 penetrates the cavity, the cavity where the first melt 20 is disposed is partially sealed by a piston structure 701 to form an arc extinguishing chamber 702, and the arc extinguishing chamber 702 is filled with an arc extinguishing medium, which is a material capable of extinguishing an arc, such as sand. A certain displacement distance is left between the impact end face of the piston structure 701 and the open end of the cavity. The piston structure 701 is made of an insulating material.

The piston structure 701 is provided with a limiting structure at a contact surface with a housing of the transmission device, for example, a bump 703 is provided at the contact surface of the piston structure 701, and a groove is provided at the contact surface of the housing of the transmission device, so that the bump is embedded in the groove to form the limiting structure, so as to maintain an initial position of the piston structure 701. The inner peripheral wall of the shell of the transmission device is provided with a sliding groove, and the piston structure 701 is clamped in the sliding groove and can move along the sliding groove. The piston structure 701 is in sealing contact with the housing of the transmission device, and sealing can be achieved through a sealing ring or interference fit. When the piston structure 701 is displaced under the driving of the arc energy generated by the fusing of the first melt, the arc extinguishing medium in the arc extinguishing chamber 702 will not leak due to the sealing effect of the piston structure 701.

The third lead 601 and the fourth lead 602 of the first trigger circuit 60 are disposed on the outer periphery of the housing of the transmission device, and are respectively connected with the first conductor 10 and the second conductor 30 in an electrically conductive manner, and the connection manner is through welding, bolt fixing or other manners. One end of the third conducting wire 601 and one end of the fourth conducting wire 602 are bent and located in front of the displacement direction of the piston structure 701, and a sufficient insulation distance is reserved between the two ends, as shown in fig. 7.

The first switch 50 is disposed in front of the impact end face displacement of the piston structure 701. The first switch 50 includes two conductive connectors 501 arranged in parallel at an interval, and a weak breaking point 5011 for reducing mechanical strength is provided on the conductive connectors 501.

The conductive connector 501 is arranged at one end of the cavity opening of the transmission device shell, and a sufficient insulation distance is reserved between the third conducting wire 601 and the fourth conducting wire 602, and the conductive connector 501 is positioned between the third conducting wire 601 and the fourth conducting wire 602 and the impact end face of the piston structure 701. When the piston 701 is displaced, the conductive connecting piece 501 is disconnected, and then the conductive connecting piece portion at the end connected with the first excitation source is driven to displace, so that the conductive connecting piece portion is in conductive contact with the third conducting wire 601 and the fourth conducting wire 602, and the first trigger circuit is in conductive connection with the first excitation device.

A wiring groove 704 is formed on the outer peripheral side of the housing of the transmission device 70, and the first lead 4011 and the second lead 4012 are electrically connected to one end of the conductive connecting member 501 after passing through the wiring groove 704, respectively. Instead of being connected to the first excitation source through a wire, the conductive connection member 501 may be extended at one end to be directly connected to the first excitation source.

One end of the conductive connecting member 501 is connected to the signal receiving end of the first excitation source 401 through a wire, and the other end is a free end or the other end of the conductive connecting member 501 may also be electrically connected to the external signal trigger circuit 450.

When the fault current is low current, the first fused mass 20 is fused, the generated electric arc is small and can be instantly extinguished, the first fused mass 20 is disconnected with a circuit, and the first exciting device does not act because the generated electric arc energy is small and cannot drive the piston structure to act; when the fault current is a large current, the first melt 20 is fused to generate a large arc, an arc is formed at the fused position of the first melt, the circuit cannot be disconnected through the fusing of the first melt, the energy of the generated arc is large, the piston structure 701 can be driven to overcome the limiting structure to move, the weak disconnection position of the conductive connecting piece 501 is cut off, the piston structure 701 continuously drives the conductive connecting piece 501 connected with the first excitation source 401 to move partially, and the conductive connecting piece is in conductive connection with the third wire and the fourth wire to connect the first trigger circuit and the first excitation device.

Example 8

This embodiment is a modification made on the basis of embodiment 5.

The first melt 20 is connected in series between the first conductor 10 and the second conductor 30. Referring to fig. 15, the second excitation device 80 is disposed at the first melt 20, i.e., the first melt 20 is located within the second excitation device 80. The second trigger circuit 90 is connected in parallel at both ends of the first melt 20 located outside the second excitation device 80, and the second trigger circuit 90 is electrically connected to the second excitation source 801. When the first melt 20 is fused, the second trigger circuit sends a trigger signal to the second excitation source, and the second excitation source acts to drive the second cutting device to act to cut off the first melt 20. Because the second cutting device is made of insulating materials, the second cutting device is positioned at the cut-off position of the first melt body 20 when the second cutting device cuts off the first melt body 20, and the cut-off position of the first melt body 20 is insulated and isolated.

An arc-quenching medium is provided in the second excitation device 80 at the first melt 20. The structure of the second shut-off device for breaking the first melt disposed in the arc-extinguishing medium is known from the prior art and will not be described in detail here.

The two ends of the first fused mass 20 positioned outside the second excitation device 80 are also connected with a second fused mass 100 in parallel, and the resistance value of the second fused mass 100 is higher than that of the first fused mass 20, such as constantan wire and the like. An actuator 70 is arranged at the second melt 100, and the connection between the external trigger circuit and the first excitation source is cut off through the action of the actuator 70, so that the first trigger circuit is driven to be in conductive connection with the first excitation source.

In normal operation, current flows through the first melt 20, and only a small portion of the current flows through the second melt 100. Therefore, the resistance of the second melt 100 is much greater than the resistance of the first melt 20. When the first melt 20 melts, most of the current passing through the first melt 20 flows through the second melt 100, and the second melt 100 melts, and the second melt melts to drive the actuator 70 to act.

When the second melt is fused, if the actuator 70 is driven by the arc energy, the structure of the actuator 70 can be referred to the actuator structure of embodiment 7.

In this example, another transmission structure is described. Referring to fig. 16, the transmission 70 includes a housing having a cavity open at one end. The bottom of the cavity of the housing is an insulating bottom cover 706, and a spring 705, an insulating piston structure 701, a conductive connector 501, a first conducting wire 4011 and a second conducting wire 4012 are arranged in the cavity of the housing. An insulating bottom cap 706 closes one end of the housing. One end of the spring 705 is fixedly disposed on the insulating bottom cap 706. The piston structure 701 is located at the other end of the spring 705. The second melt 100 passes through an insulating bag cover 706 and a spring 705, and then passes through a piston structure 701, and a draw hook is arranged on the piston structure 701 to bind the piston structure 701. Spring 705 is compressed between insulating bottom cap 706 and piston structure 701 by restraining piston structure 701. The piston structure 701 closes the cavity of the housing, and the piston structure 701 can be displaced along the housing under the action of an external force. An arc extinguishing medium is filled in a cavity of the housing between the piston structure 701 and the insulating cover plate 706.

One end of the third conducting wire 601 and one end of the fourth conducting wire 602 of the first trigger circuit 60 are disposed at the end face of the cavity opening end of the housing of the transmission device 70, and are located in front of the displacement direction of the piston structure 701, and a sufficient insulation distance is reserved between them. The other ends of the third conducting wire 601 and the fourth conducting wire 602 are respectively connected to two ends of the first fused mass 20, which are located outside the second excitation device, the connection mode is connected through welding, bolt fixing or other modes, and the first trigger circuit 60 is connected in parallel with the first fused mass 20.

The first switch 50 includes two conductive connection members 501 arranged in parallel at an interval, and a breaking weak point for reducing mechanical strength is provided on the conductive connection members 501.

The conductive connector 501 is arranged at one end of the cavity opening of the transmission device shell, and a sufficient insulation distance is reserved between the third conducting wire 601 and the fourth conducting wire 602, and the two conductive connectors 501 are positioned between the third conducting wire 601 and the fourth conducting wire 602 and the impact end face of the piston structure 701. When the piston structure 701 is displaced, after the conductive connecting member 501 is disconnected, the conductive connecting member 501 at one end connected to the first excitation source 401 is driven to be partially displaced, so that the conductive connecting member is respectively in conductive contact with the third conducting wire 601 and the fourth conducting wire 602, and the first trigger circuit 60 is electrically connected to the first excitation device 40.

Referring to fig. 17, the second excitation device 80 includes a housing, a second excitation source 801, a second shut-off device 802, and the first melt 20 located within the housing. The second trigger circuit 90 is electrically connected to the signal receiving terminal of the second excitation source 801 through a wire. The adjacent ends of the first conductor 10 and the second conductor 30 are provided with breaking weak points which reduce the mechanical strength, and the breaking weak points are V-shaped notches. In the housing of the second excitation device 80, a first melt housing 201 is arranged on the periphery of the first melt 20, and the first melt housing 201 is clamped at the breaking weak point of the adjacent end of the first conductor 10 and the second conductor 30. An arc-extinguishing medium is filled in the first melt housing 201. The first melt shell 201 and the second cutting device are made of insulating materials. The first melt shell 201 can be displaced relative to the shell of the second excitation device under the drive of external force.

When the first melt 20 is fused, the second trigger circuit 90 is conducted, the second trigger circuit 90 collects the voltage of the first melt 20 and sends the voltage as a trigger signal to the second excitation source 801, the second excitation source 801 acts to drive the second cut-off device 802 to displace and drive the first melt shell 201 to displace and cut off from the adjacent weak cut-off positions of the first conductor 10 and the second conductor 30. The arc generated when the first melt 20 melts is extinguished by the arc extinguishing medium.

The working principle is as follows:

When a fault current occurs, the first melt 20 is fused, after the first melt 20 is fused, the second trigger circuit 90 is conducted, a trigger signal is sent to a second excitation source of the second excitation device, the second excitation source acts to drive the second cut-off device to drive the first melt shell 201 to move, the first melt shell 201 is cut off from the weak cut-off position at one end of the first conductor adjacent to the second conductor, the first melt shell 201 drives the first melt to be separated from the first conductor and the second conductor, and an electric arc generated by the first melt is extinguished in an arc extinguishing medium in the first melt shell 201.

After the first melt 20 is fused, current flows through the second melt 100, the second melt 100 is fused, the spring 705 is not bound, under the action of elastic force, the piston structure 701 is displaced to cut off the conductive connecting piece 501, and drives the disconnected conductive connecting piece 501 to be displaced, and the conductive connecting piece 501 is respectively in conductive connection with the third lead and the fourth lead, so that a first trigger circuit and a first excitation device are switched on, a trigger signal is sent to the first excitation device, and the first excitation device acts to disconnect the first conductor 10 and break a circuit. The arc generated by the melting of the second melt 100 is extinguished in the arc extinguishing medium.

The second melt is connected in parallel at the first melt, so that the transmission device is not restricted to be arranged on one side of the first melt, and the transmission device can be arranged at a position far away from the first melt according to the actual structure requirement. Meanwhile, as the second melt with higher resistance is connected in parallel, when current flows through the second melt, the current on the second melt is reduced, and when the second melt is fused, the generated arc is smaller, the generated arc energy is small, and the circuit is easy to extinguish the arc and break. Therefore, when the second fuse element is connected in parallel, the arc energy at the second fuse element is reduced, and in order to ensure that the first trigger circuit is conducted with the first excitation source, the spring force is preferably used as the driving force.

Alternatively, the piston structure 701 may be bound to the first melt 20 without connecting the second melt 100 in parallel, and the piston structure 701 may be unbounded by fusing the first melt 20, so as to drive the piston structure 701 to operate under the action of an elastic force.

Claims

1. A high-reliability active and passive integrated protection device is characterized by comprising a first conductor, a first melt, a second conductor and a first excitation device, wherein the first conductor, the first melt and the second conductor are sequentially connected in series;

the first melt is connected with a first trigger circuit in parallel;

under the normal working state of the first melt, the first trigger circuit is not conducted with the first excitation device;

2. The integrated high-reliability active-passive protection device according to claim 1, wherein the signal receiving terminal of the first excitation device is electrically connected to an external signal trigger circuit for transmitting the trigger signal to the first excitation device.

3. The active-passive integrated protection device with high reliability as claimed in claim 2, wherein when the first melt is in an arc state after being melted, the signal receiving terminal of the first excitation device is driven to be disconnected from the external signal trigger circuit, and then the first excitation device is electrically connected with the first trigger circuit to provide the trigger signal for the first excitation device.

4. The active-passive integrated protection device with high reliability as claimed in claim 3, wherein a third trigger circuit is connected in parallel with the first fuse element, and the third trigger circuit is electrically connected with the first excitation device; when the first melt normally works, the third trigger circuit does not send a trigger signal to the first excitation device, and when the first melt is fused, the third trigger circuit sends a trigger signal to the first excitation device.

5. The high-reliability active-passive integrated protection device according to claim 3, further comprising a second excitation device, wherein the second excitation device receives a trigger signal to open the first conductor;

the first melt is also connected with a second trigger circuit in parallel, and the second trigger circuit is in conductive connection with a signal receiving end of a second excitation device;

when the first melt works normally, the second trigger circuit does not send a trigger signal to the second excitation device; when the first melt melts, the second trigger circuit sends a trigger signal to the second excitation device.

6. The active and passive integrated protection device with high reliability as claimed in claim 5, wherein the second excitation device comprises a second excitation source and a second cut-off device, the first fuse body is arranged in the first fuse body housing in a penetrating manner, when the first fuse body melts, the second trigger circuit is conducted to send an excitation signal to the second excitation source, the second excitation source acts to drive the second cut-off device to displace, and the first fuse body housing is driven to drive the first fuse body to displace integrally and separate from the first conductor and the second conductor.

7. The integrated protection device of any one of claims 1 to 6, further comprising a transmission device, wherein a first switch device is disposed at one end of a wire of the first trigger circuit or the first excitation device, when the first fuse melts, the transmission device is driven to operate under the action of arc energy or elastic force, and the transmission device drives the first switch device to operate, so that the first trigger circuit is electrically connected to the signal receiving end of the first excitation device to provide a trigger signal for the first excitation device.

8. The integrated high-reliability active-passive protection device according to claim 7, wherein the first switch device is electrically connected to a signal receiving end of the first excitation device, and the first excitation device is electrically connected to an external trigger signal circuit through the first switch device; when the first melt is fused, the transmission device is driven to act under the action of arc energy or elasticity, and the transmission device drives the first switch device to act to disconnect the first excitation device from the external trigger signal circuit, so that the first trigger circuit is in conductive connection with the lead of the first excitation device through the first switch device.

9. The high-reliability active-passive integrated protection device according to claim 8, wherein the first switch device is two conductive connecting pieces, and two ends of each conductive connecting piece are respectively and electrically connected with the external trigger signal circuit and the signal receiving end of the first excitation device through wires; when the first melt is fused, the arc energy generated by the first melt drives the transmission device to act, and after the transmission device disconnects the conductive connecting piece, the conductive connecting piece part which is conductively connected with the first excitation device is driven to be conductively connected with the first trigger circuit.

10. The high-reliability active-passive integrated protection device according to claim 8, wherein the first melt is connected in parallel with a second melt; the transmission comprises a spring and piston structure; the second melt restrains the spring in a compressed state; when the first melt is fused, the second melt is fused, the piston structure acts under the action of elasticity, and the first trigger circuit is driven to be in conductive connection with the signal receiving end of the first excitation device so as to provide a trigger signal for the first excitation device.

11. The integrated high-reliability active-passive protection device according to any one of claims 8 or 10, wherein the first melt or the second melt is located in a cavity, and the transmission device closes the cavity.

12. The high reliability active-passive integrated protection device according to claim 11, wherein the transmission device is a flexible film enclosing the first melt or the second melt; or the transmission device is of a piston structure.

13. The high reliability active-passive integrated protection device of claim 11, wherein the cavity in which the first melting body or the second melting body is located is filled with an arc-extinguishing medium.

14. The integrated high-reliability active-passive protection device according to any one of claims 1 to 6, 8 to 10 and 12 to 13, wherein the first trigger circuit comprises a transformer, the high-voltage circuit of the transformer is connected in parallel with the first fuse body, and the low-voltage circuit of the transformer is not conducted with the first excitation device; when the first melt works normally, the low-voltage circuit of the transformer is not conducted with the first excitation device; when the first melt melts, the arc energy generated by the melting of the first melt can drive the low-voltage circuit of the transformer to be in conductive connection with the signal receiving end of the first excitation device, and the first trigger circuit sends a trigger signal to the first excitation device.

15. The active-passive integrated protection device with high reliability as claimed in claim 14, wherein a conduction detection device for controlling the on-off of the circuit is connected in series with the high-voltage circuit of the transformer.

16. The integrated high-reliability active-passive protection device according to claim 15, wherein the conduction detection device is an active or passive device.