A fault detection and faulted-phase selection approach for transmission lines with Haar wavelet transform

Wavelet transform is a novel signal processing technique and has been widely used in many applications, including power system disturbance analysis. Many published woks introduce the wavelet transform as a tool to analyze power system disturbances. In this work, a dyadic wavelet transform based approach, which is used to detect transmission line faults, is proposed. The coefficient of discrete approximation of the dyadic wavelet transform with Haar wavelet is used to be an index for transmission line fault detection and faulted-phase selection. Basic ideas and the proposed algorithm are described in this paper. MATLAB/Simulink is used to generate fault signals and verify the correctness of the algorithm. Simulation results reveal that the performance of the proposed fault detection indicator is promising and easy to implement, for computer relaying application.