Classification of Transmission Line Faults Using Wavelet Transformer

In general fault analysis is carried out for a given system assuming various types of fault currents are estimated based on the configurations. It is proposed to implement Discrete Wavelet Transformer (DWT) approach for fault classification once the fault currents are known in a particular location. Daubechies eight (D-8) wavelet transforms of the three phase currents on a transmission line fed from both ends is used. An algorithm is implemented for the classification of faults in the transmission line using MATLAB-SIMULINK software. The advent of large generating stations and highly interconnected power systems makes early fault detection and rapid equipment isolation imperative to maintain system stability. In analyzing the fault are existing methods like Fourier analysis, Short Time Fourier Transforms and Fast Fourier Transforms have the limitations of fixed window and poor resolution. If wavelet transforms are opted, they overcome the above disadvantages, as wavelet transforms employ analysis functions that are localized both in time and frequency domain. It focuses on short-time intervals for high frequency components and long-time intervals for low frequency components. Wavelets have a window that automatically adapts to give appropriate resolution.