Leakage current detection circuit and leakage current protection circuit

Abstract

A leakage current detection circuit and a leakage current protection circuit are disclosed. The leakage current detection circuit includes a mutual inductance module, an excitation module, a signal processing module, a feedback self-check module and a calculation module. The mutual inductance module includes a magnetic core, a first winding and a second winding. The excitation module is configured for producing an excitation current in the first winding. The signal processing module is configured for processing the output voltage signal of the first winding and outputting a processed signal, and the voltage signal corresponding to the excitation current is filtered out of the processed signal. The feedback self-check module includes a feedback circuit and a self-check circuit. The calculation module is configured for analyzing the leakage current according to the processed signals and outputting the self-check signal in the self-check mode.