An Integrated High Impedance Fault Detection Approach for Renewable Penetrated Distribution Network

Abstract

The conventional overcurrent relay used in the microgrid system is unable to detect high impedance fault. The magnitude of fault current is very less or same as the normal load current during high impedance fault and thus relay finds difficulty in detecting the fault. In the proposed method, the wavelet decomposition approach is applied to extract the order of higher frequency component present in the instantaneous current signal. The db4 mother wavelet is used to decompose the current signal and the third decomposed level is used to estimate the Teager Kaiser Energy Operator. The energy operator is consistently zero for no-fault and normal power system operating conditions, but rise significantly with the initiation of high impedance fault. The proposed is tested for different values of fault resistance, capacitor charging and nonlinear load switching conditions. The modified IEEE 13 bus distribution system integrated with hybrid distributed generators is considered for simulation analysis. The performance of the proposed HIF detection technique is compared with other existing techniques. The results prove the efficacy of the proposed integrated approach.