Asymmetric Fault Location of Distribution Network Based on Positive and Negative Sequence Voltage Ratio

This paper introduces an accurate fault distance determination for distribution network utilizing the positive and negative sequence voltage ratio. The distribution characteristics of the ratio between positive and negative sequence voltage (RPN) in the whole network is used to determine the fault segment, and then the RPN of the two ends of the fault section or the first two points of the segment is used to acquire the fault distance. The RPN of the corresponding points on the fault path can be known through the data of measurement point at the end of the non-faulty path, which solves the problem that it is hard to acquire information directly from both ends of the faulted section in the existing double-end location method. The proposed method has been verified by IEEE34 node system to achieve accurate location of asymmetric faults in distribution networks rich in clean energy resources, and its location performance is not influenced by the system grounding modes, and it has strong robustness to measurement errors, fault resistance and load changes, and shows better results on high resistance faults.