Bistable contactor driving circuit

Abstract

The invention relates to a bistable contactor driving circuit, which comprises a bistable contactor, and also comprises a switching tube Q and a relay RLY 1. A ninth moving contact and a fourth moving contact of the relay RLY 1 are connected to the two ends of a coil of the bistable contactor respectively, while a tenth normally closed contact and a fifth normally open contact are connected to an anode of a power supply; an eighth normally open contact and a third normally closed contact of the relay RLY 1 are connected to a collector of the switching tube Q; an emitter of the switching tube Q is connected to a cathode of the power supply, while a base is connected to the output end of a switching tube driving circuit; and the coil of the relay RLY 1 is connected with an output anode and an output cathode of a driving voltage generation circuit for generating a relay driving voltage respectively. The bistable contactor driving circuit in the invention has the advantages of high reliability, long service life, strong antistatic and over-voltage protection capacity, small volume, and small occupied PCB area by the circuit due to the adoption of the miniature relay.

Description

technical field [0001] The invention relates to a bistable contactor in power electronics technology, and more specifically relates to a bistable contactor drive circuit. Background technique [0002] The bistable (magnetic holding) contactor can work in two states of normally open and normally closed, and does not need to provide energy to maintain the state. Because of its stability and energy saving, it is popularized and adopted in the industry. However, the drive control is relatively complicated, which limits the further promotion of the bistable contactor. The driving coil of the bistable contactor has polarity, and a positive pulse of a certain width is applied to the negative pole, and the bistable contactor changes from an open state to a closed state. Similarly, a negative pulse is applied to change from closed to open . Different bistable contactors may require different pulse widths and amplitudes (e.g. figure 1 Shown) The specific parameters are provided by ...

AI Technical Summary

Problems solved by technology

The disadvantage of this control method is: the bridge circuit composed of MOSFET tubes is easily damaged by static electricity during operation, resulting in control failure

a class such as image 3 As shown, it is a two-way switching circuit composed of two relays. This circuit has good isolation performance, but since the operating voltage of general relays is less than 30VDC, and the application of 48V communication power supply has a lot of excess voltage derating, it is necessary to use a larger rated current. For example, to drive a contactor of about 3A, a 2C relay with a rated current of more than 8A should be selected, which is large in size and difficult to meet the current miniaturization requirements

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