A novel online fault locating method for multiple branch complex distribution networks

On the basis of deducing the equations about fault distance and electric parameters on the feeder of the distribution network after fault, a novel online fault locating algorithm for multiple branch complex distribution networks has been proposed in this paper. It firstly gets all nodes voltages and the line currents through pre-fault power flow calculation, and sets up the branch equivalent models of distribution network. When the fault occurs in the network, according to the real-time data of the voltage and current value on the feeder, the recursive power flow calculation is executed, searching within each sections until the fault point is found. This new fault locating algorithm considers the characteristics of the distribution network,such as multiple branches, three-phase unbalance, fault resistance uncertainty and the load fluctuations, etc. Simulations and tests on a small distribution network verifies that, the proposed algorithm has good robustness and high precision, realizing online fault location for the complex distribution network, and makes the distribution network online self-healing control possible.