Virtual Fault Resistance-Based High Impedance Fault Section Location for Active Distribution Networks

Accurate identification and location of high impedance fault (HIF) in medium voltage distribution network is one of the technical problems in the industry. In this paper, a HIF location method based on virtual fault resistance is proposed. Firstly, the phase voltage and phase current phasors of the first cycle wave after the fault are obtained by Discrete Fourier Transform (DFT) algorithm, and then the virtual fault resistance values of each phase are calculated. Then, the fault is located according to whether the Coefficient of Variation of each section exceeds the threshold. The proposed method is still applicable after distributed generators (DGs) access, and is not affected by the operation mode. It can identify HIF in both effective grounding and non-effective grounding of neutral points. A simulation model is built in PSCAD to verify the effectiveness of the proposed HIF section location method.