A Novel Two-terminal Asynchronous Fault Location Method Based on Exchange Traveling Wave Information in Fault Section

At present, two-terminal fault location method is based on the time difference of first arrival traveling waves (TWs) between two ends, which need time alignment and its accuracy may be affected by the clock synchronization error. To solve this problem, this paper use wavefront time series of TWs detected at two-terminal for fault location in distribution networks. Firstly, the voltage TWs signal which acquired by feeder terminal unit (FTU) is processed with the Haar wavelet transform technique to extract the wavefront time series of fault TWs. Secondly, the FTU at two-terminal of the fault section exchange wavefront time series, then the first wavefront of two ends can be aligned by the modulus maximum of detail coefficients. Finally, the time difference between the first and second overlap wavefront is used to calculate the fault distance. The simulation results based on PSCAD show that the error of proposed method is less than 50 m, which is not affected by the fault resistance and initial phase angle.