Transient earth fault detection on compensated earthed system

A new technique to detect the fault direction of single-phase-to-earth fault for Petersen´s Coil compensated earthed power system is presented in this paper. The proposed technique can make a precise decision on detecting the single-phase-to-earth fault, not requiring higher frequency sampling rates, higher accuracy measurements. It can be implemented in traditional feeder relay with low sampling rate. Presently, the technique has been implemented in an already commercial available relay from author´s company.