Traveling wave fault location in coal mine power transmission systems

Coal mines distribution network is a non-solid earthed power transmission system, which are routinely subjected to single phase to ground fault, when fault appears, fault current is weak, which is very difficult to find the fault point. Because of the wave speed is not sure, the existing methods of fault location based on traveling waves are not perfect. In this paper, a new fault location method is presented in which the influence of wave speed is eliminated. The traveling wave signal can be detected by wavelet transform, by analyzing the polarities of the initial traveling wave and reflected wave from the fault point and the opposite bus, different components of the traveling wave can be distinguished. The simulation results confirmed the feasibility of this method.