A novel fault location method of a 35-kV high-reliability distribution network using wavelet filter-S transform

Abstract

Timely and accurate fault location for a 35-kVhigh-reliability distribution network is one of the key technologies to improve the safety and efficiency of distribution network operations. A novel fault location method of 35-kV high-reliability distribution network is proposed in this paper. First, the distributed multipoint fault location model is established based on the power structure of a 35-kV high-reliability distribution network. The distribution of voltage and current traveling waves along the lines is comprehensively considered in this model. Secondly, we analyze the influence of noise interference, analog-digital conversion frequency, and conversion bits on the location accuracy. The simulation method of noise and analog-digital conversion is proposed based on simulated samples. Then, a wavelet filter is used to reduce the influence of noise on the calibration of the traveling wave arrival time, and matrix modulus of S transform is used to identify the arrival time for the wave. Finally, the simulation model of a 35-kV high-reliability distribution network is established to analyze the location accuracy in the case of single-phase to ground via resistance, two-phase short-circuit to ground via resistance, and three-phase short-circuit faults. The simulation results indicate that the proposed method has high location accuracy under the above fault conditions.