Study on the technology of leakage protection

Failure leakage of equipment or electric shock may make the residual current amplitude decrease, which causes effective protection of the fault and the existence of dead zone of operation. This paper presents the principle of residual current leakage protection based on vector, using residual current amplitude and residual current variation of fault leakage protection, the realization of mutation leakage, continuous slow change leakage detection and recognition, triangle formulas residual current variation calculation method, orthogonal decomposition calculation method and three-phase equivalent calculation method. Through the analysis of the residual current vector variation, we put forward the corresponding method of delayed electrical leakage protection. According to the residual current amplitude, mutation leakage, slowly varying leakage, electric leakage comprehensive protection, we can reduce the leakage protection action area; improve the reliability of power system. © 2014, Zixing et al.