An improved fault line selection method based on traveling waves in non-solid earthed network

In this research, the procedure of the transient traveling wave in non-solidly earthed network is analyzed. It shows that at the bus bar the traveling waves of healthy lines are mainly composed of the refracted traveling waves. The refracted are generated from the backward traveling wave in the fault line, then the refracted traveling waves is the main part of the traveling waves in the healthy lines; besides, in fault line the energy of the transient traveling waves is much larger than the healthy lines, and accordingly peak values can be used to show the traveling wave energy. Considering the complex conditions in application, fault line may not be correctly selected only using one criteria, especially in the high resistance fault and the zero crossing fault. For this reason, combined and improved fault line selected method is presented. The ATP simulation shows that the combined rules for fault line selection is effective.