A SYSTEM AND METHOD FOR INRUSH AND FAULT DETECTION FOR DIFFERENTIAL PROTECTION OF TRANSFORMER

摘要

A novel system and method for the differential protection of power transformer is sighted using time frequency transformation known as a matched wavelet transformation which is used to detect inrush and fault currents and also to individuate fault and inrush currents even though when inrush current is generated during fault conditions. The differential protection consists of a differential relay which outputs a trip signal for internal faults and block or restrain signal for inrush currents. This matched wavelet transformation method gives more accurate results even in the presence of noise inputs and accurately identifies inrush and fault currents.