A Method for Distribution Network Section Location Based on Similarity of Zero-sequence Instantaneous Reactive Power Waveforms

To address the issue of accurately detecting high resistance ground faults in the neutral ungrounded system, a novel method for distribution network section location based on the similarity of zero-sequence instantaneous reactive power waveforms is suggested. Firstly, an analysis of the ungrounded system transient behavior is conducted, leading to the derivation of analytical equations for the zero-sequence voltage and zero-sequence current. Based on the zero-sequence voltage and current, zero-sequence instantaneous reactive power is conducted. Then, the similarity between zero-sequence instantaneous reactive power waveforms at both ends of different sections is compared by spearman correlation coefficient to determine the faulty section. The simulation results indicate that the suggested method is immune to the transition resistance and has the ability to locate the section with high resistance ground faults. Even under different initial fault angles and sections, the suggested method can correctly recognize the faulty section, which has a promising potential for practical application.