Alternating current electronic switch device

Abstract

The invention discloses an alternating current electronic switch device which comprises a switching module (1), an absorption circuit (2), a discharging circuit (3) and a controller (15). The switch module (1) is used for quickly switching on and off alternating current, and the absorption circuit (2) and the discharge circuit (3) are used for absorbing energy when the switch module (1) is switched off and protecting the normal work of the switch module (1). The controller (15) communicates with an upper computer and is used for controlling the normal operation of the functions of the parts. The power electronic switch device is simple in structure, low in cost, small in loss, high in reliability and high in switching speed.

Description

technical field [0001] The invention belongs to the technical field of electrical engineering, and in particular relates to an AC electronic switch device that can be turned on and off quickly. Background technique [0002] AC electronic switches are also called solid-state electronic switches, which can control the on and off of AC current. In applications, thyristors are often used in parallel to achieve, such as figure 1 shown. AC electronic switches can be easily controlled by weak current signals, such as MCU, which is very convenient to be used in many occasions and has a good application prospect. [0003] Although the solid-state switch composed of anti-parallel thyristors has the advantages of high voltage and high current, it cannot be turned off by a weak current signal, so its use is greatly limited in the occasions that need to be turned off quickly. [0004] Published patent 201310260839.4 discloses an electronic switch based on IGBT, such as figure 2 As sh...

AI Technical Summary

Problems solved by technology

[0003] Although the solid-state switch composed of anti-parallel thyristors has the advantages of high voltage and high current, it cannot be turned off by a weak current signal, so its use is greatly limited in the occasions that need to be turned off quickly

[0004] Published patent 201310260839.4 discloses an electronic switch based on IGBT, such as figure 2 As shown, it can quickly realize the bidirectional cut-off and conduction of the current, but each set of switches needs 2 capacitors and 2 discharge resistors. If it is used to form a multi-way switch (such as a commonly used three-phase switch), it needs twice the number of switches capacitors and resistors, so the number of components is large, the cost is high, and it needs to lead out the middle point of the switch, the circuit is complicated, which affects the reliability of the device; in addition, the voltage of the capacitor is uncontrollable. When the switch is in the on state, the capacitance gradually Discharge to zero voltage, and when the switch is turned off again, the main circuit current will continue to flow through the capacitor, charging the capacitor from zero voltage, so the open technology has a long turn-off time and cannot achieve fast turn-off

[0005] like image 3 In the prior art shown, although the circuit is simple, when a fault such as overcurrent or short circuit occurs and the switch needs to be turned off, it is difficult for the RC snubber circuit to completely absorb the induced voltage. Therefore, MOV devices, such as varistors, etc. are added. However, this type of anti-surge protection device has low reliability, and will fail when the impact energy is large or multiple impacts occur, resulting in a decrease in the life and reliability of the device.

[0006] It can be seen that the solid-state electronic switch circuit structure in the prior art still has unsatisfactory problems such as complex structure, high cost, low reliability, and slow speed.

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