A new fault location scheme based on distributed short-circuit current in distribution system with DGs

Nowadays, with more and more renewable energy sources connecting to the radial distribution network, the coordination of over-current relays might be lost. Instead of improving the traditional protection method of the distribution system, this paper proposes a novel protection scheme which can be used in the system with high DG penetration, characterized by DG participating in fault location. Proposed fault location scheme is based on such characteristic that for a given short-circuit fault type, the fault current contribution from each power source in the system will change continuously and monotonically as the fault point moves along the line towards a certain direction, and this characteristic is not affected by the other DG connection. Having been proved in the paper, this characteristic is used for the proposal of a novel fault location method. Tested on the IEEE 34 Node Test Feeder with PSS/E30.1, the validity of the new fault location method was verified.