Relay arc extinction circuit and control device

Abstract

The present invention provides a relay arc extinction circuit and a control device. The relay arc extinction circuit comprises: a relay comprising a magnet exciting coil and a contact switch; a diodeconnected in parallel with the magnet exciting coil and configured to provide a short-circuit channel for high-voltage pulses generated by the magnet exciting coil; and a contact protective circuit connected with the contact switch of the relay and configured to protect the contact switch when the magnet exciting coil generates the high-voltage pulses. The contact protective circuit comprises a protective capacitor connected in parallel with two ends of the contact switch, a protective resistor connected in series with the protective capacitor and a piezoresistor connected in parallel with twoends of the contact switch. The relay arc extinction circuit is simple and reasonable in the structure of the relay arc extinction circuit, effectively achieves arc extinction of relay at a breakingcurrent moment, avoids generation of high-voltage arc discharge when the magnet exciting coil of the relay is interrupted, has a good control effect on arc discharge of the contact of the relay in suction and releasing states, and is high in work reliability.

Description

technical field [0001] The invention relates to the technical field of electronic circuits, in particular to relays, in particular to a relay arc suppressing circuit and control equipment. Background technique [0002] The basic function of the switching device is to be able to open and close the circuit in the required short time, that is, to play the role of the so-called switch. The mechanical switch device uses contacts to break the circuit current. When the circuit is broken in the atmosphere, As long as the voltage exceeds 12-20V and the interrupted current exceeds 0.25-1A, a group of approximately cylindrical gas with extremely high temperature, strong light and conductivity is usually generated in the contact gap (also called arc gap). It's the arc. [0003] There are two types of relay arcing: relay contact arcing. A high-voltage arc is generated when the excitation coil of the relay is de-energized. Arcing can ablate contacts, reducing relay life and reliability...

AI Technical Summary

Problems solved by technology

[0005] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a relay arc suppression circuit and control equipment for solving the problem of poor arc suppression effect of the relay in the prior art

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