Distribution Feeder Fault Detection Method Considering Transient Frequency Response of Distributed Power Supply

Abstract

Single-phase ground faults can occur in distribution networks, which bring harm to the safe operation of distribution networks. With the continuous development of new energy technology, distributed power supply is also accessed to the distribution network in large quantities. This paper analysed the impact of distributed power supply from the perspective of its transient frequency response. It explores the changing rules and characteristics of the fault travelling wave in the frequency and time domains, revealing its time–frequency–amplitude three-dimensional characteristics. Accordingly, a detection method based on energy distribution characteristics is proposed, and the thresholds for startup and fault detection are given. The sensitivity of the startup criterion and the accuracy of fault detection are verified through simulation analysis, and the method is able to identify transient disturbances and faults, and also has a certain anti-interference ability. In addition, experimental validation was carried out in a physical test field, and the results show that the proposed method is applicable in practical application scenarios.