Remote control determining the location of power lines damaged with single phase ground fault

The authors provide a method of determining the distance to location of the single-phase earth faults in networks with an isolated or compensated neutral. Determination of distance to fault location in medium voltage networks is a complex task in technical terms because of the strong and extensive network and large transient resistance values at the fault location. High accuracy of the proposed method is based on the voltage resonance phenomenon. There is a significant increase in current in the resonance mode, which is a reliable sign of the fault location. Resonance is provided with applying a high frequency current from an additional source of sinusoidal voltage connected to the mains. The distance to the location of the single-phase ground fault in this case is proportional to the length of the test signal wavelength. The principles of practical realization of the device for determining the distance to the fault location are presented. The developed method has been tested in a real power network. Tests have proved stability and accuracy of the determination of the distance to location of the single-phase ground fault at different values of transient resistance in the fault location.