Incorporating earth fault location in management-control scheme for distribution networks

This study integrates earth fault location computation with fault management-control schemes for distribution networks. To realise this target, a panel substation is located at the lateral outlet. The faulted section is identified precisely via a fault-location algorithm. Then, isolating the faulted section is accomplished through control signals between the lateral-panel substation and the faulted section isolators. The service restoration is achieved by a direct communication between the lateral-panel substation and the feeder primary substation. The proposed fault-location algorithm is based on the pure fault circuit with the initial condition of the earth fault using the measurements at each lateral panel. For phase-to-ground fault, the initial condition is the series connection for the sequence networks from the fault point. For phase-to-phase-to-ground fault, the initial condition is that the summation of the sequence currents at the fault point is equal to zero. The proposed fault-location algorithm is, therefore, suitable for equipping distribution systems with distributed generation. Moreover, it is applicable for earthed or unearthed networks with all possibilities of transformer connection and load taps. For investigation purposes, simulation tests are performed using the IEEE 33-bus automated feeder example. The simulation test results corroborated the efficacy of the proposed fault management system.