Power Network Fault Location Using Traveling Waves and Continuous Wavelet Transform

Faults in a power network will cause propagation of traveling waves within the network. This paper proposes a new traveling wave based fault location method in a power network. For each terminal, the arrival time of the first wavefronts at the terminal is captured, to avoid the impact of complex reflections within the network. To accurately capture the arrival time and to reduce the impact of measurement noises, the tool of continuous wavelet transform (CWT) is adopted. The coefficients from CWT are normalized for each frequency, and the peak of the coefficient summation of different frequencies corresponds to the arrival time of wavefronts. With the arrival time information of traveling waves and line network parameters, the accurate fault section and fault location are determined. Simulation results show that, with measurement noises, the fault location accuracy of the proposed CWT based method is higher in comparison to methods with discretized wavelet transform (DWT), for various fault locations, types and transition resistances.