An Accurate Fault-Location Method for Distribution Network with Distributed Generators Based on Multi-Terminal Traveling Wave

Since more and more distributed generators (DGs) are connected into the low voltage distribution network, the existing fault-location methods are difficult to achieve accurate fault location due to its decentralized power supply characteristics. Aiming at this problem and the shortcomings of the existing traveling-wave fault-location methods, this paper proposes an accurate fault-location method for distribution networks with DGs based on multi-terminal traveling wave. Firstly, this paper analyzes the impact of DGs on the first arrival times of the fault-generated traveling waves. Secondly, a set of fault distance data independent of traveling-wave velocity are calculated by using the traveling-wave time information of all detectors, and the faulted branch is identified based on the discrete degree of this set of data. Finally, the quartile method is used to reject the bad data, and the accurate fault distance of the fault point is obtained. Simulation results show that the proposed method can accurately locate the fault point, hardly impacted by traveling-wave velocity, and has good robustness to arrival time errors.