CN113366595B

CN113366595B - Arc extinguishing power device driving device

Info

Publication number: CN113366595B
Application number: CN202080007975.0A
Authority: CN
Inventors: 郭桥石; 刘建德; 贾宝华
Original assignee: Guangzhou Kingser Electronics Co ltd
Current assignee: Guangzhou Kingser Electronics Co ltd
Priority date: 2019-06-23
Filing date: 2020-06-22
Publication date: 2023-08-22
Anticipated expiration: 2040-06-22
Also published as: WO2020259424A1; CN113366595A

Abstract

The arc extinguishing power device driving device is an arc extinguishing power device driving device which is suitable for an electronic arc extinguishing device and is used for driving a power device, a power device (SCR 1) to be driven is connected with a required arc extinguishing mechanical switch (K1) in parallel, the arc extinguishing power device driving device comprises a voltage detection switch (A) and a capacitor (C1), the voltage detection switch (A) is used for detecting voltages at two ends of the power device (SCR 1), the capacitor (C1) drives the power device (SCR 1) to be conducted through the voltage detection switch (A) in the working process of breaking the mechanical switch (K1), and the voltage detection switch (A) is a full-control switch with a conduction threshold value larger than the on-state voltage of the power device (SCR 1) under the condition of forward voltage of the power device (SCR 1); the voltage detection switch (A) is a semi-controlled switch under the condition of reverse voltage of the power device (SCR 1). The method has the advantages of strong interference resistance, good stability and short on time of the power device.

Description

Arc extinguishing power device driving device

Technical Field

The invention relates to an arc extinguishing power device driving device, in particular to a driving device for driving a power device, which is suitable for an electronic arc extinguishing device of a mechanical switch.

Background

At present, in an electric control system, when a mechanical switch such as a relay performs breaking control on a load, breaking arc is large, and the defect that the electrical life of the mechanical switch is short exists is overcome, so that an electronic arc extinguishing device which is connected with the mechanical switch in parallel by utilizing a thyristor, for example, a patent number of 201710029448.X is named as an arc extinguishing power device driving device and an arc extinguishing device, and a first voltage detection switch disclosed in the patent adopts a semi-controlled switch or a fully-controlled switch with a conduction threshold value smaller than the on-state voltage of a power device.

It has the following disadvantages:

1. when the first voltage detection switch adopts a semi-controlled switch, the mechanical switch coil is disturbed when the mechanical contacts are not separated when the mechanical switch coil is powered off, or the mechanical switch is broken to jump (such as a manual mechanical switch and a three-phase switch are easy to break and bounce), the capacitor is easy to discharge in advance, the arc extinction is unstable, and arc extinction failure is easy to cause.

2. When the first voltage detection switch adopts a fully-controlled switch with the on threshold value smaller than the on-state voltage of the power device, the first voltage detection switch has high sensitivity and is also easily interfered, or the mechanical switch is broken to generate jumping, the capacitor is easily discharged in advance, the arc extinction is unstable, and arc extinction failure is easily caused.

Disclosure of Invention

The invention aims to provide an arc-extinguishing power device driving device which has strong interference resistance, good stability and short power device on time and aims to overcome the defects of the technical scheme in the background technology.

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

the power device to be driven is connected in parallel with a mechanical switch to be extinguished, and the device comprises a voltage detection switch and a capacitor, wherein the voltage detection switch is used for detecting the voltage at two ends of the power device; the voltage detection switch is a semi-controlled switch under the condition of reverse voltage of the power device.

Working principle: as shown in fig. 1, in the working process of breaking the mechanical switch K1, the voltage detection switch a is turned on when the voltage at two ends of the power device SCR1 is greater than the turn-on voltage (between about 1 and 2 volts), the capacitor C1 drives the power device SCR1 to be turned on through the voltage detection switch a, if the mechanical switch K1 is bounced and turned off, and when the mechanical switch K1 is turned off again, the voltage detection switch a is turned on again, so as to achieve the purpose of breaking and extinguishing the mechanical switch K1; when the voltage detection switch A is conducted when the voltage at two ends of the power device SCR1 is reverse voltage, the capacitor C1 is rapidly discharged through the voltage detection switch A, and the capacitor C1 is prevented from driving the power device SCR1 to conduct again in the next working period.

The invention has the advantages of reasonable design, strong interference resistance, good stability and short on time of the power device.

Drawings

Fig. 1 is a schematic circuit diagram of a driving device for an arc suppressing power device according to the present invention.

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

Fig. 3 is a schematic diagram of a voltage detection circuit of the arc suppressing power device driving apparatus of the present invention.

Detailed Description

In a first embodiment of the driving device for an arc suppressing power device of the present invention, as shown in fig. 2:

the power device SCR1 (semi-controlled device, unidirectional thyristor) to be driven is connected in parallel with the mechanical switch K1 to be extinguished, and comprises a voltage detection switch A and a capacitor C1, wherein the voltage detection switch A is used for detecting the voltage at two ends (anode and trigger pole or anode and cathode) of the power device SCR1, and in the working process of breaking the mechanical switch K1, the voltage detection switch A is conducted when the voltage at two ends of the power device SCR1 is larger than the conducting voltage of the power device SCR1, and the capacitor C1 is conducted through the voltage detection switch A to drive the power device SCR1, so that the aim of breaking and extinguishing the mechanical switch K1 is achieved.

Voltage detection switch a: as shown in fig. 3, the semiconductor device is composed of resistors (R2 to R10), and semiconductor devices (including transistors and diodes); is a full-wave voltage detection switch; it appears as a semi-controlled switch under the condition of reverse voltage of the power device SCR 1; the power device is a fully-controlled switch under the condition of forward voltage of a power device SCR 1; the full-control type voltage detection switch is composed of a full-control type voltage detection circuit (switch) for detecting forward voltage of a power device and a half-control type voltage detection circuit (switch) for detecting reverse voltage of the power device, and a transistor Q1, a transistor Q2 and a diode Z2 form the full-control type voltage detection switch; the transistors Q3, Q4, Q5, and Q6 form a half-controlled voltage detection switch, and the circuit formed by connecting the transistors Q3, Q4, Q5, and Q6 is a circuit formed by driving the thyristor equivalent circuits (Q5 and Q6) by the transistors (Q3 and Q4), where the thyristor equivalent circuits formed by connecting the transistor Q5 (NPN transistor) and the transistor Q6 (PNP transistor) are connected in series in the driving circuit of the power device TR1, and the circuit of the voltage detection switch a is not limited to the circuit of fig. 3, but can be implemented by other circuits.

In the working process of breaking the mechanical switch K1, when the power device SCR1 is in forward voltage and is larger than the on threshold value of the voltage detection switch A (at least larger than the voltage stabilizing value of the voltage stabilizing device Z1, preferably), the capacitor C1 drives the power device SCR1 to be conducted through the transistor Q1 of the voltage detection switch (when the mechanical switch K1 is in bouncing closing state, the transistor Q1 is cut off and arc-extinguished, and when the power device SCR1 is in reverse voltage, the transistor Q5 and the transistor Q6 of the voltage detection switch A (the transistor Q5 and the transistor Q6 form a thyristor equivalent circuit) discharge the capacitor C1 at one time, so that the next cycle conduction of the power device SCR1 is avoided; when two unidirectional power devices SCR1 are used in anti-parallel, two sets of power device driving devices (the current limiting elements R2 can be multiplexed) are also needed, and in order to ensure that only one of the two unidirectional power devices SCR1 is conducted in the breaking process of the mechanical switch K1, the conduction threshold value of the voltage detection switch A under the condition of forward voltage of the power device SCR1 is larger than that of the voltage detection switch under the condition of reverse voltage of the power device SCR 1.

The power supply circuit also comprises a unidirectional conduction device D1 (diode), a current limiting element R1 (resistor), wherein the current limiting element R1, the unidirectional conduction device D1 and a capacitor C1 are connected in series to form a series circuit, one end of the series circuit is connected with a power supply, the power supply is provided by a power grid where the power device SCR1 is positioned in a non-isolated mode, the other end of the series circuit is connected with a cathode of the power device SCR1, and the capacitor C1 forms a driving loop through a voltage detection switch (A), a trigger electrode of the power device SCR1 and the cathode of the power device SCR 1; the voltage stabilizing device Z1 is connected with the capacitor C1 in parallel through the unidirectional conduction device D1, or the voltage stabilizing device Z1 is directly connected with the capacitor C1 in parallel, and the voltage stabilizing device Z1 is used for reducing the voltage withstand requirement of the voltage detection switch (A). The power device SCR1 adopts half-controlled devices such as unidirectional thyristors and the like, and has the advantages of low cost and good overload capacity.

In the above embodiment, the working energy of the voltage detection switch a is provided by the capacitor C1, and the input loop of the voltage detection switch a, the output loop of the voltage detection switch a and the power device SCR1 are not insulated (i.e. no photoelectric isolation and electromagnetic isolation exist), so that the voltage detection switch has the advantage of low cost; the capacitor C1 may be connected to a switch or current limiting element for charging the capacitor C1.

The capacitor C1 has low capacity requirement, when the thyristor for driving tens of amperes adopts 1 microfarad capacitor, the requirement can be met, the nonpolar capacitor (ceramic capacitor and the like) can be adopted, the plastic packaging process with the temperature of more than 150 ℃ is convenient, and the capacitor is packaged into a universal device, and is convenient to popularize and use.

In summary, the invention can ensure that the capacitor can provide enough driving energy in the bouncing process of the contact, and the voltage detection switch is a semi-controlled switch to realize the rapid discharging of the capacitor during the reverse voltage period of the power semiconductor, thereby preventing the power device in the next period from being triggered and conducted again and reducing the conduction time of the power device.

Claims

1. The utility model provides an arc extinguishing power device drive arrangement, the power device that needs driven and the parallelly connected of required arc extinguishing mechanical switch, it includes a voltage detection switch, a electric capacity, voltage detection switch is used for detecting the voltage at power device both ends, in the work process that mechanical switch divides the section, electric capacity passes through voltage detection switch drive power device switches on, characterized by: the voltage detection switch is a full-control switch with a conduction threshold value larger than the on-state voltage of the power device under the condition of the forward voltage of the power device; the voltage detection switch is a semi-controlled switch under the condition of reverse voltage of the power device.

2. The arc suppressing power device driving apparatus according to claim 1, wherein: the input loop of the voltage detection switch, the output loop of the voltage detection switch and the power device are not insulated.

3. The arc suppressing power device driving apparatus according to claim 1, wherein: the operating energy of the voltage detection switch is provided by the capacitor.

4. The arc suppressing power device driving apparatus according to claim 1, wherein: the forward conduction threshold of the voltage detection switch is greater than the reverse conduction threshold of the voltage detection switch.

5. The arc suppressing power device driving apparatus according to claim 1, wherein: the voltage detection switch consists of a resistor and a semiconductor device.

6. The arc suppressing power device driving apparatus according to claim 1, wherein: the voltage stabilizing device is connected with the capacitor in parallel or connected with the capacitor in parallel through a unidirectional conduction device.

7. The arc suppressing power device driving apparatus according to claim 1, wherein: the power device is a semi-controlled device.

8. The arc suppressing power device driving apparatus according to claim 1, wherein: the power device is a unidirectional thyristor.

9. The arc suppressing power device driving apparatus according to claim 1, wherein: the capacitor is connected with a switch or a current limiting element for charging the capacitor.

10. The arc suppressing power device driving apparatus according to claim 9, wherein: the power device comprises a power device, a current limiting element, a unidirectional conduction device, a capacitor and a power circuit, wherein the current limiting element, the unidirectional conduction device and the capacitor are connected in series to form a series circuit, one end of the series circuit is connected with a power supply, the other end of the series circuit is connected with a cathode of the power device, and the capacitor forms a driving loop through the voltage detection switch, a trigger electrode of the power device and the cathode of the power device.