Grounding Fault Line Selection Method of Distribution Network Based on Time-Frequency Domain Energy Matrix

In view of the limitation of the method of line selection based on single fault characteristic in distribution network, this paper proposes a distribution ground fault line selection method based on time-frequency domain energy matrix. Firstly, the zero sequence current transient signal detected by the intelligent pole switch when the fault occurs is extracted, and the fault panoramic information matrix containing time frequency energy multi-dimensional features is constructed through LCD decomposition. Then the similarity of panoramic information matrix of adjacent detection points is calculated, and the reliable line selection of the fault line is realized according to the similarity. The simulation results show that this method comprehensively utilizes the time-frequency domain characteristic information of transient signals, and is less affected by high resistance fault conditions, distribution network structure and other factors. It can effectively improve the accuracy of distribution network fault line selection, has high adaptability and reliability, and has simple algorithm principle and fast calculation speed.