Location for high impedance fault and polluted insulator in transmission line-based non-linear frequency analysis

The efficiency of power systems is based mainly on the continuity of the service, avoiding faults that suppose economic losses for utilities and users. It is very important to detect, locate and eliminate the faults of power systems, especially on power transmission lines. This paper presents a new method based on non-linear frequency analysis for online detection and location of the high impedance faults on power transmission lines, which has been one of the most difficult problems in power transmission and distribution systems. The proposed technique is based on the non-linear characteristics of the high impedance faults and severely contaminated insulators on power lines. The non-linear frequency responses related to the signal of power line carrier were used to detect the occurrence of the high impedance fault. The location of the fault and the degraded insulator on the power lines could be determined by detecting the position of the non-linear component in the power transmission system. The effectiveness of the method has been verified through simulation studies. The results demonstrated that the proposed method has the potential to be applied in practice to resolve high impedance fault real time monitoring problem.