WO2021129562A1

WO2021129562A1 - Arc extinction switch and method for using same

Info

Publication number: WO2021129562A1
Application number: PCT/CN2020/137951
Authority: WO
Inventors: 郭桥石
Original assignee: 郭桥石
Priority date: 2019-12-23
Filing date: 2020-12-21
Publication date: 2021-07-01
Also published as: CN114830277A

Abstract

An arc extinction switch and a method for using same. A mechanical switch (K) that needs arc extinction is connected to a load (RL); a semiconductor switch (S1) is provided; a reverse withstand voltage value of the semiconductor switch (S1) is greater than a forward withstand voltage value thereof; during the breaking of the mechanical switch (K), a power source (U1) supplies power to the load (RL) by means of the semiconductor switch (S1) for the arc extinction for the mechanical switch (K); and the forward withstand voltage value is less than a voltage value of the power source (U1). The arc extinction switch has the advantage of a low cost.

Description

Arc extinguishing switch and its use method

Technical field

The invention relates to an arc extinguishing switch and a use method thereof, in particular to an arc extinguishing switch suitable for extinguishing an arc of a medium and high voltage mechanical switch (or other breakpoint) and a use method thereof.

Background technique

At present, when electronic arc extinguishing is performed on mechanical switches above several kilovolts, high-voltage semiconductor devices are required as the arc extinguishing switches, which has the disadvantage of high cost.

Summary of the invention

The purpose of the present invention is to solve the problem of high cost of the medium and high voltage arc extinguishing switch, and to provide a low-cost arc extinguishing switch and a method of use thereof.

The purpose of the present invention is achieved through the following technical solutions:

An arc extinguishing switch, a mechanical switch that requires arc extinguishing is connected to a load. It is a semiconductor switch. The reverse withstand voltage value of the semiconductor switch is higher than its forward withstand voltage value. During the breaking process of the mechanical switch, a power supply passes through the semiconductor switch. It supplies power to the load and is used to extinguish the arc of the mechanical switch. The forward withstand voltage value is less than the voltage value of the power supply.

A method of using an arc extinguishing switch. The difference between the voltage value of the power supply and the voltage value at both ends of the load is less than the forward withstand voltage value.

Working principle: As shown in Figure 1, the semiconductor switch S1, the mechanical switch K required to extinguish the arc is connected to the load RL, the reverse withstand voltage value of the semiconductor switch S1 is higher than the forward withstand voltage value of the semiconductor switch S1, and the mechanical switch K During the breaking process, the semiconductor switch S1 is controlled to be turned on, and the power supply U1 supplies power to the load RL through the semiconductor switch S1, so as to achieve the purpose of extinguishing the arc of the mechanical switch K.

The invention has the advantage of low cost.

Description of the drawings

Fig. 1 is a schematic diagram of the arc extinguishing switch and its use method of the present invention and one of the schematic diagrams of the first embodiment thereof.

Fig. 2 is the second schematic diagram of the first embodiment of the arc extinguishing switch and its use method of the present invention.

Detailed ways

The first embodiment of the arc extinguishing switch and its control method of the present invention:

As shown in Figure 1, the semiconductor switch S1 is composed of a thyristor SCR1 (unidirectional thyristor) and a diode D1 in series. When the mechanical switch K is disconnected, the power U1 can be provided by a capacitor. The capacitor is fully charged first, and the mechanical switch K is disconnected. The semiconductor switch S1 is turned on, and the power supply U1 supplies power to the load RL through the semiconductor switch S1, and the potential difference between the two ends of the load RL is increased to achieve the purpose of arc extinguishing of the mechanical switch K; because the mechanical switch K is breaking, its arc voltage is much lower than that of the semiconductor switch The forward voltage of S1 (between tens of volts to hundreds of volts), the forward withstand voltage value of the semiconductor switch S1 can be much smaller than the voltage value of the power supply U1 and the working voltage of the load RL, assuming a voltage value of 10 kV The power supply U1 extinguishes the arc on the mechanical switch K connected to the load RL with a working voltage of 10 kilovolts, and the forward withstand voltage of the semiconductor switch S1 is 1 kilovolt (the thyristor SCR1 can meet the working needs of ordinary thyristors). As long as the reverse withstand voltage value of the semiconductor switch S1 is greater than the working voltage of the load RL, a common thyristor is used in series with several common diodes, and the mechanical switch with a voltage of 10 kilovolts and a current of several hundred or thousands of amperes can be turned off. Arc control.

Choosing the semiconductor switch S1 to have a forward withstand voltage value smaller than the voltage value of the power supply U1 is beneficial to reduce the cost of the semiconductor switch. The reverse withstand voltage value of the semiconductor switch S1 is greater than the voltage value of the power supply U1 (or both ends of the load RL) to prevent the semiconductor switch S1 from being positive. To breakdown, the difference between the voltage value of the power supply U1 and the voltage value across the load U1 is not greater than the forward withstand voltage value; the reverse voltage of the semiconductor switch S1 is provided first, and then the forward voltage of the semiconductor switch S1 is provided; or the semiconductor switch is provided The rising rate of the forward voltage of S1 (the voltage across U1) is less than that of the reverse voltage of the semiconductor switch S1 (the voltage across the load RL). It is recommended that the reverse withstand voltage of the semiconductor switch S1 is greater than its forward withstand voltage Twice the value.

As shown in Figure 2, after the mechanical switch K is closed, the voltage across the load RL charges the capacitor connected to the power supply U1 through the resistor R1 and the diode D2. During the breaking process of the mechanical switch K, the capacitor C1 passes through the diode D1 and the Zener diode Z1 triggers the thyristor SCR1 to be turned on, and the power supply U1 supplies power to the load RL through the semiconductor switch S1, and the potential difference between the two ends of the load RL increases to achieve the purpose of arc extinguishing of the mechanical switch K.

Note: The embodiment of the present invention is DC arc extinguishing, it can also be used for AC arc extinguishing (synchronous arc extinguishing), and related components can be added for AC arc extinguishing or bidirectional DC arc extinguishing as needed; the above embodiment, semiconductor switch S1 It is not limited to using a thyristor in series with a diode (it has the advantages of simple circuit and flexible design), but a (specially made) unidirectional thyristor with a reverse withstand voltage 1.5 times higher than the forward withstand voltage can also be used.

The mechanical switch of the present invention includes a controllable disconnected mechanical switch, a fault breakpoint, and other breakpoints that can generate arcs.

In summary, the present invention breaks through the inertial thinking of those skilled in the art that the forward withstand voltage value of the arc extinguishing switch needs to be higher than the voltage value of the arc extinguishing power supply. The invention is especially suitable for arc extinguishing in medium and high voltage systems with voltages above several thousand volts, and the arc extinguishing switch of the invention has the advantage of low cost.

Claims

An arc extinguishing switch, a mechanical switch that requires arc extinguishing is connected to a load, and is characterized in that it is a semiconductor switch, and the reverse withstand voltage value of the semiconductor switch is higher than the forward withstand voltage value of the semiconductor switch, so During the breaking process of the mechanical switch, a power supply supplies power to the load through the semiconductor switch for arc extinguishing of the mechanical switch, and the forward withstand voltage value is less than the voltage value of the power supply.
The arc extinguishing switch according to claim 1, wherein the semiconductor switch is composed of a thyristor and at least one diode in series, and the diode and the thyristor form a series circuit.
The arc extinguishing switch according to claim 2, wherein the thyristor is a unidirectional thyristor.
The arc extinguishing switch according to claim 1, wherein the reverse withstand voltage value is higher than the working voltage of the load.
The arc extinguishing switch according to claim 1, wherein the difference between the voltage value and the voltage value at both ends of the load is less than the forward withstand voltage value.
The arc extinguishing switch according to claim 1, wherein the power supply is provided by a capacitor.
A method for using an arc extinguishing switch according to any one of claims 1 to 5, characterized in that: the reverse voltage of the semiconductor switch is provided first, and then the forward voltage of the semiconductor switch is provided; or the semiconductor switch is provided The rate of increase of the forward voltage of the switch is less than the rate of increase of the reverse voltage of the semiconductor switch.
The method of use according to claim 7, wherein the power supply is provided by a capacitor, and the capacitor is fully charged first, and a power supply supplies power to the load through the semiconductor switch during the disconnection process of the mechanical switch.