CN112753085B

CN112753085B - Arc extinguishing device

Info

Publication number: CN112753085B
Application number: CN201980062895.2A
Authority: CN
Inventors: 郭桥石
Original assignee: Guangzhou Kingser Electronics Co ltd
Current assignee: Guangzhou Kingser Electronics Co ltd
Priority date: 2018-10-25
Filing date: 2019-10-24
Publication date: 2023-07-28
Anticipated expiration: 2039-10-24
Also published as: CN112753085A; WO2020083323A1

Abstract

An arc extinguishing device, in particular to an arc extinguishing device suitable for arc extinction of a mechanical switch (K) such as a contactor (relay), and the like, comprising a first capacitor (C1) and a detection switch (A), wherein the detection switch (A) is connected with the first capacitor (C1) and is used for detecting the change rate of voltage of a common end of a load (M) and the mechanical switch (K), the change rate reaches the starting value of the detection switch (A), the detection switch (A) is conducted, and the first capacitor (C1) supplies power to the load (M) through the detection switch (A). The arc extinguishing device has the advantages of strong voltage fluctuation resistance and good arc extinguishing effect.

Description

Arc extinguishing device

Technical Field

The invention relates to an arc-extinguishing device, in particular to an arc-extinguishing device suitable for arc extinction of mechanical switches such as a contactor (relay), and the like, and can also be used for arc extinction of other breakpoints (such as fusing of a fuse link, breakpoints between a plug and a socket and breakpoints of a wire).

Background

At present, in electric control systems such as new energy automobiles, rail transit, ships and automatic control, a mechanical switch such as a contactor (relay) is commonly used for carrying out frequent switching-on and switching-off control on a load, and as the mechanical switch has a switching-off arc, particularly direct current, the switching-off arc is larger due to no zero point, and the defect of short electric life of the mechanical switch exists, the electric life of the mechanical switch is greatly reduced along with the improvement of the switching-off voltage and the switching-off current of the mechanical switch.

Disclosure of Invention

The invention aims to solve the problem of short electrical life of a mechanical switch in the existing electric control system and provides an arc extinguishing device for extinguishing arc by utilizing a capacitor by detecting the voltage change rate of a common terminal of the mechanical switch and a load.

The aim of the invention is achieved by the following technical scheme:

an arc extinguishing device is shown in fig. 1, and comprises a first capacitor C1 and a detection switch A, wherein the detection switch A is connected with the first capacitor C1, the detection switch A is used for detecting the change rate of the voltage of the common end of a load M and a mechanical switch K, the change rate reaches the starting value of the detection switch A, the detection switch A is conducted, and the first capacitor C1 supplies power to the load M through the detection switch A.

Working principle: in the breaking process of the mechanical switch K, when the contact of the mechanical switch K is broken, the change rate (namely the falling rate) of the voltage of the common end of the load M and the mechanical switch K changes into the rising rate when the second capacitor C2 of the detection switch A is connected with the power supply of the power end of the mechanical switch K, the first capacitor C1 supplies power to the load M through the detection switch A (the power supply energy can be provided by the charge stored in advance by the first capacitor C1, the grounding end of the first capacitor C1 can be changed into the power supply connection with the power end of the mechanical switch K, the power supply is provided by the first capacitor C1 and the detection switch A), the voltage of the two ends of the load M rises rapidly, and the potential difference of the two ends of the mechanical switch K drops rapidly, so that the aim of arc extinction of the mechanical switch is achieved.

The invention has reasonable design, uses the change rate of the detection voltage of the detection switch to carry out arc extinction, and has the advantages of strong voltage fluctuation resistance, high arc extinction accuracy and good arc extinction effect.

Drawings

Fig. 1 is a schematic circuit diagram of an arc suppressing apparatus of the present invention.

Fig. 2 is a schematic circuit diagram of an embodiment of the arc suppressing apparatus of the present invention.

Fig. 3 is a schematic diagram of a second circuit of an embodiment of an arc suppressing apparatus according to the present invention.

Fig. 4 is a schematic diagram of a second circuit of an arc suppressing apparatus according to the second embodiment of the present invention.

Fig. 5 is a schematic diagram of a third circuit of an embodiment of the arc suppressing apparatus of the present invention.

Fig. 6 is a schematic diagram of a delay cell circuit of a detection switch of the arc extinguishing device of the present invention.

Fig. 7 is a schematic diagram of a delay cell of a detection switch of the arc extinguishing device of the present invention.

Fig. 8 is a schematic diagram of the equivalent circuit of a thyristor of a detection switch of the arc extinguishing device of the present invention.

Fig. 9 is a second schematic circuit diagram of a third embodiment of the arc suppressing apparatus of the present invention.

Fig. 10 is a schematic diagram of an embodiment of an arc suppressing apparatus according to the present invention.

Fig. 11 is a schematic diagram of a fifth circuit of an embodiment of the arc suppressing apparatus of the present invention.

Fig. 12 is a sixth schematic view of an embodiment of an arc suppressing apparatus according to the present invention.

Fig. 13 is a waveform diagram of the voltage across a load without employing the arc suppressing apparatus of the present invention.

Fig. 14 is a second waveform of the voltage across the load using the arc suppressing apparatus of the present invention.

Fig. 15 is a third waveform of the voltage across the load using the arc suppressing apparatus of the present invention.

Fig. 16 is a waveform diagram of the voltage across the load using the arc suppressing apparatus of the present invention.

Detailed Description

An embodiment of the arc extinguishing device of the present invention is shown in fig. 2:

an arc extinguishing device comprises a first capacitor C1 and a detection switch A, wherein the detection switch A is connected with the first capacitor C1, the detection switch A is used for detecting the change rate of voltages at two ends of a load M (namely, the change rate of a common end of the load M and a mechanical switch K relative to the voltage at the ground end of the load M), the change rate (the falling rate) of the voltages at the two ends of the load M reaches the starting value of the detection switch A, the detection switch A is conducted, and the first capacitor C1 supplies power to the load M through the detection switch A;

the charging unit B consists of a first diode D1 and a first current limiting element R1 (resistor) which are connected in series;

detection switch A: the switch is a semi-controlled switch and comprises a second capacitor C2, a controllable device SCR1 and a second diode D2 (options), wherein the voltage at two ends of a load M drives the controllable device SCR1 to be conducted through the first capacitor C1, the second diode D2 and the second capacitor C2; the working energy of the detection switch A and the voltage signal are provided by a first capacitor C1; the common terminal of the second diode D2 and the second capacitor C2 is connected to the common terminal of the first diode D1 and the first current limiting element R1, and the third diode D3 (option) is connected to the trigger electrode and the cathode of the controllable device SCR 1.

Working principle: the mechanical switch K is connected with the load M in series, the mechanical switch K is closed, the voltage at two ends of the load M charges the first capacitor C1 through the charging unit B, when the mechanical switch K is closed and bounces or the switch K is disconnected, the first capacitor C1 drives the controllable device SCR1 to be conducted through the second diode D2 and the second capacitor C2, the first capacitor C1 supplies power to the load M through the controllable device SCR1, the voltage at two ends of the load M rises rapidly, the potential difference at two ends of the mechanical switch K drops rapidly, and the aim of arc extinction of the mechanical switch is achieved.

The embodiment has the advantages of small number of used components and simple circuit.

In a second embodiment of the arc extinguishing device of the present invention, as shown in fig. 3:

the arc extinguishing device comprises a first capacitor C1 and a detection switch A, wherein the detection switch A is connected with the first capacitor C1 and is used for detecting voltages at two ends of a load M, the change rate (falling rate) of the voltages at two ends of the load M reaches the starting value of the detection switch A, the detection switch A is turned on, and the first capacitor C1 supplies power to the load M through the detection switch A;

the charging unit B is composed of a first diode D1 (option) and a first current limiting element R1 (resistor) which are connected in series.

Detection switch A: the semi-controlled switch comprises a second capacitor C2, a controllable device SCR1, a second current limiting element R2 (resistor, option) and a second diode D2 (option), wherein the semi-controlled switch is a three-terminal circuit (the first capacitor C1 can be used as a selection switch for arc extinction of a multi-path mechanical switch in multiplexing mode), the second capacitor C2, a parallel circuit formed by the second current limiting element R2 and the second diode D2, and a trigger electrode of the controllable device SCR1 are connected in series, a third terminal 3 of the detection switch A can be connected with the second terminal 2 instead, and is used as a two-terminal circuit (the working energy and voltage signals of the detection switch A are provided by the first capacitor C1), and the third diode D3 (option) is connected with the trigger electrode and a cathode of the controllable device SCR 1.

Working principle: the mechanical switch K is closed, the voltage at two ends of the load M charges the first capacitor C1 through the charging unit B, the voltage at two ends of the load M charges the second capacitor C2, when the mechanical switch K is closed and bounces or the switch K is disconnected, the second capacitor C2 drives the controllable device SCR1 to be conducted, the first capacitor C1 supplies power to the load M through the controllable device SCR1, the voltage at two ends of the load M rises rapidly, the potential difference at two ends of the mechanical switch K drops rapidly, and the aim of arc extinction of the mechanical switch is achieved.

In this embodiment, the power ground terminal of the first capacitor C1 may be connected to the power source terminal of the mechanical switch K instead (as shown in fig. 4), the third current limiting element R3 (resistor) is used for discharging the first capacitor C1, the charging unit B becomes the discharging unit B, and when the switch K is closed and bounces (during the bounce closing period, the first capacitor C1 is rapidly discharged through the mechanical switch K and the discharging unit B) or the switch K is disconnected, the second capacitor C2 drives the controllable device SCR1 to be turned on, and the power source supplies power to the load M through the first capacitor C1 and the controllable device SCR 1.

A third embodiment of the arc extinguishing device according to the present invention is shown in fig. 5:

detection switch A: the switch is a semi-controlled switch, which consists of a second capacitor C2, a controllable device SCR1 and a delay unit C, is a two-end circuit, and is used for detecting the working energy and voltage signals of a switch A and providing the working energy and voltage signals by the first capacitor C1; the third terminal 3 of the detection switch a may be connected to ground instead, and used as a three-terminal circuit (when the three-terminal circuit is used, the ground terminal of the first capacitor C1 may be connected to the power supply of the power supply terminal of the mechanical switch K instead), and the voltage signal is transmitted to the delay unit C through the second capacitor C2, where the delay unit C drives the controllable device SCR1 to be turned on.

And a delay unit C: as shown in fig. 6, the circuit is composed of a power supply circuit (a fifth current limiting element R5, a fifth voltage stabilizing device Z5), a delay circuit (a transistor Q1, a semiconductor device Z7, a fourth capacitor C4), and a semi-controlled switch (a thyristor SCR2, which may be replaced by a circuit as shown in fig. 8), wherein the power supplied by the first capacitor C1 is limited by the fifth current limiting element R5, the voltage of the fifth voltage stabilizing device Z5 is stabilized to supply working energy to the delay circuit, a parallel circuit composed of a second capacitor C2 and a second current limiting element R2 (resistor) and a second diode D2, and an input circuit of the delay unit C are connected in series, and in order to increase the driving force, the circuit of fig. 7 may also be adopted, and the following is noted: the circuits shown in fig. 6, 7 and 8 are preferred, and other digital circuits may be used.

Working principle: the mechanical switch K is connected with the load M in series, the mechanical switch K is closed, the voltage at two ends of the load M is used for charging the first capacitor C1 through the detection switch A (through an internal circuit thereof, a charging unit B can be added, and reference is made to fig. 3), the voltage at two ends of the load M is used for charging the second capacitor C2, when the mechanical switch K is in a breaking process, the second capacitor C2 drives the semi-controlled switch SCR2 to be conducted, the controllable device SCR1 is driven to be conducted through the delay circuit (the delay time is more than 100 microseconds, a certain opening distance is reserved between contacts of the mechanical switch K), the first capacitor C1 is used for supplying power to the load M through the controllable device SCR1, the voltage at two ends of the load M is rapidly increased, and the potential difference at two ends of the mechanical switch K is rapidly decreased, so that the aim of arc extinction of the mechanical switch is achieved.

In the high voltage and high current situation, to further improve the arc extinguishing stability, a circuit as shown in fig. 9 may be adopted:

the circuit is based on fig. 5, and further comprises a third capacitor C3, a fourth current limiting element R4 (resistor), a first charging unit B1 (composed of a first diode D1 and the first current limiting element R1 connected in series, or alternatively, the first diode D1 and the first current limiting element R1), a first voltage stabilizing device Z1 (option), a second charging unit B2 (composed of a tenth current limiting element and a tenth diode connected in series, or alternatively, the tenth current limiting element R1 and the tenth diode) and a third capacitor C3 and the fourth current limiting element R4 connected in series to form a first series circuit; the first charging unit B1 and the first capacitor C1 form a second series circuit; the first capacitor C1, the detection switch A and the third capacitor C3 form a third series circuit, the voltage at two ends of the load M charges the third capacitor C3 by using the first series circuit, and the voltage at two ends of the load M charges the first capacitor C1 by using the second series circuit; the third capacitor C3, the second charging unit B2, and the first capacitor C1 form a fourth serial circuit, and the voltage at two ends of the load M charges the first capacitor C1 and the third capacitor C3 by using the fourth serial circuit. The first voltage stabilizing device Z1 is connected with the third capacitor C3 in parallel, and the third series circuit supplies power to the load M in the breaking process of the mechanical switch K.

The third capacitor C3 is connected in parallel with the ninth diode D9, and the eighth diode D8 connected in parallel with the first capacitor C1 is used for forming a discharging loop of the capacitor.

In this embodiment, the capacity of the third capacitor C3 (for saving volume and reducing cost, an electrolytic capacitor can be used) is larger than the capacity of the first capacitor C1, and the detection switch a of this embodiment can also be applied to the second embodiment of the present invention.

In this embodiment, the stable arc extinguishing effect can be achieved by adopting the first capacitor C1 with smaller capacity, and the arc extinguishing device is especially suitable for the occasion of high voltage and large current, and has the advantages of low cost, small volume and stable arc extinguishing.

A fourth embodiment of the arc extinguishing device according to the present invention is shown in fig. 10:

for the convenience of use, product authentication and standardized mass production, the above embodiments are packaged into devices by adopting insulating materials (the specific appearance of the devices can be flexibly designed according to the needs); when the grounding end of the first capacitor C1 in the above embodiment is changed to be connected with the power supply of the power supply end of the mechanical switch K, a pin is added.

In the above embodiment, the arc extinguishing device is a two-terminal circuit or a three-terminal circuit, and has the advantage of convenient use.

Fifth embodiment of the arc extinguishing device of the present invention is shown in fig. 11:

an arc extinguishing device comprises a first capacitor C1, a detection switch A, a control unit D and a first switch S1 (a semiconductor switch, a semi-controlled device and a unidirectional thyristor), wherein the detection switch A is connected with the first capacitor C1 and is used for detecting voltages at two ends of a load M, the change rate (falling rate) of the voltages at the two ends of the load M reaches the starting value of the detection switch A, the detection switch A is conducted, then the control unit D controls the first switch S1 to be conducted, and the first capacitor C1 supplies power to the load M through the detection switch A; during the breaking process of the mechanical switch K, and after the contact of the mechanical switch is broken for 100 microseconds (options), the first switch S1 is conducted, and the first capacitor C1, the first switch S1 and the detection switch A form a series circuit for supplying power to the load M.

Detection switch A: for the semi-controlled switch, the controllable device SCR1 and the second capacitor C2 are adopted, and a three-terminal circuit is adopted (one end of the second capacitor C2 can be connected with a power supply of a power supply end of the mechanical switch K instead), a detection switch A shown in fig. 3 and 4 is suggested to be adopted for the arc extinction selection switch of the multi-path mechanical switch. In order to prevent the controllable device SCR1 from being damaged to affect other load operations and improve the operational reliability of the controllable device SCR1, the controllable device SCR1 is connected in series with a fourth diode D4 (the circuit is designed such that the operational reliability of the fourth diode D4 is higher than that of the controllable device SCR1, which is an option).

An optocoupler detection unit (formed by an eleventh resistor R11 and an optocoupler OPT1 which are connected in series, wherein the power supply is provided by a power supply end of a mechanical switch K, the power supply can also be provided by the first capacitor C1 instead, an optocoupler OPT1 output signal is transmitted to a control unit D), the detection switch A is also connected with a fifth capacitor C5, a second capacitor C2 drives a controllable device SCR1 (semi-controllable device) to be conducted, a power supply (the power supply of the first capacitor C1 can also be provided by the power supply end of the mechanical switch K) supplies power to a load M through the fifth capacitor C5, the peak current of the fifth capacitor C5 needs to be larger than the maintaining current of the controllable device SCR1, then the fifth capacitor C5 rapidly enters a high-resistance state, the controllable device SCR1 can keep a left-right conduction state due to the fact that the optocoupler detection unit applies voltage to the controllable device SCR1, and the first switch D is convenient to control the conduction of the first switch S1 during a left-right conduction state.

Working principle: the mechanical switch K is closed, the voltage at two ends of the load M charges the second capacitor C2, when the mechanical switch K is in a breaking process, the second capacitor C2 drives the controllable device SCR1 to be conducted, then the control unit D controls the first switch S1 to be conducted (the first switch S1 is conducted for more than 100 microseconds after the controllable device SCR1 is conducted, a certain opening distance is reserved between contacts of the mechanical switch K), the series circuit formed by the first capacitor C1, the first switch S1, the fourth diode D4 (options) and the detection switch A supplies power to the load M, the voltage at two ends of the load M rises rapidly, and the potential difference at two ends of the mechanical switch K drops rapidly, so that the aim of arc extinction of the mechanical switch is achieved.

In this embodiment, the control unit D is configured to charge or discharge the first capacitor C1, or charge (reverse precharge, when the first capacitor C1 is connected to the PA end) and discharge; the PA end can be connected with a power supply of the power supply end of the mechanical switch K, the number of the mechanical switch, the detection switch and the load can be one, or two or more, the PA end shares the first capacitor C1, the first switch S1 and the control unit D, and the multiple switches can be extinguished and managed.

In this embodiment, the stable arc extinguishing effect can be achieved by adopting the first capacitor C1 with smaller capacity, which is especially suitable for the occasion of high voltage and large current, and has the advantages of low cost and stable arc extinguishing.

A sixth embodiment of the arc extinguishing device according to the present invention is shown in fig. 12:

the fifth embodiment of the arc extinguishing device is placed in a shell, and is used as a product with strong universality, and the fifth embodiment is connected with external mechanical switches, an upper computer and the like through terminals, so that the arc extinguishing device is convenient for safety authentication, popular and popularized and used, and the specific appearance of the arc extinguishing device can be flexibly designed according to requirements.

In the above embodiment, the detection switch a is used to detect the change rate of the voltage at the common end of the load M and the mechanical switch K, and since the voltage fluctuation or ripple of the power supply is much slower than the voltage change rate caused by the breaking moment of the mechanical switch K, the second capacitor C2 presents high impedance, and cannot meet the driving current requirement of the controllable device SCR 1.

In the above embodiment, the voltage signal of the detection switch a may also be provided by the power supply of the power supply end of the mechanical switch K (i.e. the voltages of the two ends of the mechanical switch K and the rising rate of the detected voltage), but is not the preferred technical solution, because the input loop of the detection switch a affects the insulation and voltage resistance of the mechanical switch K, and meanwhile, in the normal open state of the mechanical switch K, the input loop of the detection switch a is in a series connection with the load M, and there is a certain safety risk, preferably, the detection switch a is used to detect the voltages of the two ends of the load M (the voltages of the two ends of the load M may also be detected by the first capacitor C1, i.e. the voltage between the common ends of the detection switch K and the load M and the first capacitor C1), which has the greatest advantage of being convenient to inhibit the current impact of the detection switch a when the mechanical switch K is closed, and at the same time, the resolution of the change rate of the detected voltage may not be affected.

In the above embodiment, the first capacitor C1 and the detection switch a form a series circuit, the load M is connected in parallel with the series circuit, and the input circuit of the detection switch a is electrically isolated from the output circuit of the detection switch a; the detection switch A is a semi-controlled switch, and comprises a controllable device SCR1 (which is a semi-controlled device, a unidirectional thyristor, or a semi-controlled switch composed of fully-controlled semiconductor devices can be used for replacing the semi-controlled switch, such as a thyristor equivalent circuit).

In the embodiment, the detection switch A of the arc extinguishing device is composed of a second capacitor, a semiconductor device (diode, semi-controlled device) and a resistor (option), and is a two-end circuit or a three-end circuit, and the power supply of the detection switch is provided by the first capacitor, the second capacitor and the voltage at two ends of a load are not isolated; the circuit has the advantages of simplicity, low cost and strong overload capacity; the definition of the load of the present invention may also include the lines that connect for the workload.

In the above embodiment, the detection switch a couples the input signal through the second capacitor C2, and connects the second capacitor C2 in series with the trigger electrode of the controllable device SCR1 to the load M (ground terminal), or connects the power supply of the power supply terminal of the mechanical switch K, which has the advantages of no leakage current and small loss.

Fig. 13 is a waveform diagram of the voltage across the load M without employing the arc extinguishing device of the present invention;

fig. 14 is a voltage waveform diagram of two ends of a load M when the arc extinguishing device according to the second embodiment of the present invention is adopted and the first capacitor C1 is a small-capacity capacitor;

fig. 15 is a voltage waveform diagram of two ends of a load M when the arc extinguishing device according to the second embodiment of the present invention is adopted and the first capacitor C1 is a large-capacity capacitor;

fig. 16 is a voltage waveform diagram of two ends of a load M when the third embodiment or the fourth embodiment of the arc extinguishing device of the present invention is adopted and the first capacitor C1 adopts a small capacity capacitor;

the technical effects of different embodiments of the invention are obviously observed according to the comparison of waveform diagrams, and the arc extinguishing device can greatly shorten the arcing time and even realize the purpose of arc-free breaking of the mechanical switch.

In conclusion, the invention has the advantages of strong voltage fluctuation resistance and good arc extinguishing effect.

Claims

1. An arc extinguishing device is characterized in that: the detection switch is connected with the first capacitor, the detection switch is used for detecting the change rate of the voltage of the common end of the load and the mechanical switch, the change rate reaches the starting value of the detection switch, the detection switch is turned on, the first capacitor supplies power to the load through the detection switch, and the change rate is the falling rate.

2. The arc extinguishing device according to claim 1, characterized in that: the detection switch is a semi-controlled switch; the detection switch is a two-terminal circuit or a three-terminal circuit.

3. The arc extinguishing device according to claim 1, characterized in that: the input loop of the detection switch is electrically isolated from the output loop of the detection switch.

4. The arc extinguishing device according to claim 1, characterized in that: the first capacitor is connected with a power supply of a power supply end of the mechanical switch.

5. The arc extinguishing device according to claim 1, characterized in that: the voltage is the voltage across the load or the voltage between the common terminal and the first capacitor.

6. The arc suppressing apparatus according to claim 5, wherein: the detection switch comprises a second capacitor and a controllable device, and the voltage drives the controllable device to be conducted through the second capacitor; or the voltage drives the controllable device to be conducted through the first capacitor and the second capacitor, and the working energy and the voltage signal of the detection switch are provided by the first capacitor.

7. The arc suppressing apparatus according to claim 5, wherein: the detection switch consists of a second capacitor, a resistor and a semiconductor device.

8. The arc extinguishing device according to claim 1, characterized in that: the detection switch comprises a controllable device and a second capacitor, the voltage charges the second capacitor, and when the change rate reaches the detection switch starting value, the second capacitor drives the controllable device to be conducted.

9. The arc suppressing apparatus according to claim 8, wherein: the controllable device is a semi-controllable device.

10. The arc suppressing apparatus according to claim 8, wherein: the device also comprises a parallel circuit formed by a second current limiting element and a second diode, wherein the second capacitor, the parallel circuit and the trigger electrode of the controllable device are connected in series.

11. The arc extinguishing device according to claim 1, characterized in that: the voltage is the voltage at two ends of the load, the detection switch comprises a controllable device and a second capacitor, and the first capacitor drives the controllable device to be conducted through the second capacitor; the charging unit is formed by connecting a first diode and a first current limiting element in series, and the voltage charges the first capacitor through the charging unit; the detection switch further comprises a second diode, and the first capacitor drives the controllable device to be conducted through the second diode and the second capacitor; and the common ends of the second diode and the second capacitor are connected with the common ends of the first diode and the first current limiting element.

12. The arc extinguishing device according to any one of claims 1 to 10, characterized in that: the device further comprises a charging unit for charging the first capacitor.

13. The arc suppressing apparatus according to claim 12, wherein: the charging unit is a first current limiting element or is formed by connecting a first diode and the first current limiting element in series, and the voltage charges the first capacitor through the charging unit.

14. The arc suppressing apparatus according to claim 12, wherein: the arc extinguishing device is packaged into a device by adopting an insulating material.

15. The arc extinguishing device according to any one of claims 1 to 5, characterized in that: the detection switch consists of a second capacitor, a controllable device and a delay unit, wherein the voltage is transmitted to the delay unit through the second capacitor, and the delay unit drives the controllable device to be conducted.

16. The arc suppressing apparatus according to claim 15, wherein: the delay unit consists of a power supply circuit, a delay circuit and a semi-controlled switching circuit, wherein the power supply circuit consists of a fifth current limiting element and a fifth voltage stabilizing device, the working power supply provided by the first capacitor is limited by the fifth current limiting element, and the voltage stabilizing device is used for stabilizing the voltage and providing working energy for the delay circuit.

17. The arc suppressing apparatus according to claim 15, wherein: the device further comprises a third capacitor, a fourth current limiting element and a first charging unit, wherein the voltage is the voltage at two ends of the load, and the third capacitor and the fourth current limiting element form a first series circuit; the first charging unit and the first capacitor form a second series circuit; the first capacitor, the detection switch and the third capacitor form a third series circuit, the voltage charges the third capacitor by using the first series circuit, the voltage charges the first capacitor by using the second series circuit, and the third series circuit supplies power to the load in the breaking process of the mechanical switch.

18. The arc suppressing apparatus according to claim 17, wherein: the first voltage stabilizing device is connected with the third capacitor in parallel, and the third capacitor is connected with a diode in parallel.

19. The arc suppressing apparatus according to claim 18, wherein: the voltage charging circuit comprises a first capacitor, a second capacitor, a third capacitor, a second charging unit and a voltage, wherein the capacity of the first capacitor is larger than that of the second capacitor, the third capacitor, the second charging unit and the first capacitor form a first series circuit, and the voltage charges the first capacitor and the third capacitor by using the first series circuit.

20. The arc suppressing apparatus according to claim 15, wherein: the arc extinguishing device is packaged into a device by adopting an insulating material.

21. The arc extinguishing device according to any one of claims 1 to 10, characterized in that: the control unit is used for supplying power to the load in the mechanical switch breaking process.

22. The arc suppressing apparatus according to claim 21, wherein: the arc extinguishing device is placed in a shell and is connected with the mechanical switch through a terminal.

23. The arc suppressing apparatus according to claim 21, wherein: an optocoupler detection unit used for conducting the detection switch is connected between a series circuit formed by the first capacitor and the first switch and the detection switch, an output signal of the optocoupler detection unit is transmitted to the control unit, the detection switch is also connected with a fifth capacitor, and a power supply supplies power to the load through the fifth capacitor and the detection switch.

24. The arc extinguishing device according to any one of claims 1 to 5, characterized in that: the discharging unit is connected with the power supply of the power supply end of the mechanical switch, and the first capacitor discharges through the mechanical switch and the discharging unit.

25. The arc suppressing apparatus according to claim 24, wherein: the discharge unit is formed by connecting a first diode and a first current limiting element in series.