Tripping circuit and method, control circuit and electric leakage detection system thereof

Abstract

The invention provides a tripping circuit, a tripping method, a control circuit and an electric leakage detection system thereof. The tripping circuit further comprises a bias voltage unit, a couplingunit, a first switch unit and a second switch unit; the bias voltage unit pulls the voltages at the two ends of the bias voltage unit to be approximately equal when the second switch unit is turned off; when the second switch unit of the coupling unit is turned on, a voltage for turning off the first switch unit is generated through coupling. The first switch unit is controlled by a first controlsignal and provides a direct current path for the tripping coil when triggered; and the second switch unit is controlled by a second control signal, and the first switch unit is turned off through the coupling unit when the second switch unit is turned on. Compared with the prior art, the tripping circuit has the advantages that the silicon controlled rectifier can be turned off in the triggeringprocess by applying the staggered control waveform, and the mechanism is stopped from being triggered if the mechanism still cannot be tripped after a plurality of triggering waveforms, so that greater loss caused by equipment explosion is prevented.

Description

technical field [0001] The invention relates to the field of electronics, in particular to a tripping circuit, a method, a control circuit and an electric leakage detection system thereof. Background technique [0002] Leakage protection system is mainly used for electric shock protection when electric leakage fault occurs in circuit equipment and for personal electric shock with fatal danger. It has overload and short circuit protection function and can be used to protect circuit overload and short circuit. [0003] At present, for leakage protection systems, especially for rectification or DC input leakage protection systems, since the thyristor is used as the core device for tripping and driving, after the leakage occurs, the thyristor is triggered, even if it stops triggering, because the thyristor If it is not effectively turned off, the thyristor will always be on. If there is a mechanism failure (such as: adhesion, rust, impurity blockage, etc.), the tripping coil wil...

AI Technical Summary

Problems solved by technology

[0004] In order to solve this problem, the existing solution is to use high-voltage NMOS devices, IGBT devices or SiC devices as tripping drive power devices, and cooperate with digital square wave control to solve this problem, but this solution is costly, and after long-term work, Devices such as high-voltage NMOS or IGBT or SiC will have a strong Miller effect, which will cause equipment to blow up due to failure to turn off

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