Fault Location for Radial Distribution Network via Topology and Reclosure-Generating Traveling Waves

Fault location in distribution networks is difficult for multiple discontinuities, such as branches and junction points. This paper proposes a fault location scheme using network topology information and reclosure-generating traveling waves. Based on the topology, the circuit breaker closure-generating normal traveling waves (CNTWs) can be analyzed. When permanent faults occur, the circuit breaker reclosure-generating fault traveling waves (RFTWs) contain the information on fault position. The difference between the CNTWs and RFTWs, defined as reclosing superimposed traveling waves (RSTWs), is calculated. For RSTWs, their initial traveling waves are detected by wavelet transform. The time difference between the reclosing instant and the arrival instant of the reflected traveling wave of the fault point is employed to calculate the fault distance. Moreover, due to large numbers of branches, a fault distance may correspond to many sections. To determine the fault section, a database which contains the RSTWs induced by the faults occur in each section is built. The fault section can be identified by finding the most similar signals in the database by taking advantage of an improved dynamic time warping method. The simulation results indicate that the scheme can locate fault for distributed feeders regardless of grounding system type, load variation, and fault type.