Distribution System Fault Location Considering Voltage Sag Characteristics

A new on-line fault location method is proposed based on the voltage sag characteristics resulted by different faults in the power systems. Only the voltage sag measured at single end is used to locate the fault. For a given distribution system, construct a simulation model to obtain faulted section locating function and fault distance calculating function of the network. When a real short circuit fault occurs, based on the voltage waveforms or data captured from the bus, calculate the voltage sag magnitude and phase shift of the second cycle after the fault, then substitute these two values into the simulation databases, the faulted branch and the fault distance will be determined through pattern recognition technique and equation solving method respectively. Through simulating for 10 kV distribution network with bolted and non-bolted fault, it proves the method´s accuracy and reliability.