Adaptive noncommunication protection based on traveling waves and impedance relay

This paper presents an adaptive noncommunication approach for line protections that are able to classify the fault as internal or external with respect to the relay protection zone for most of the faults in radial lines and for all faults in meshed networks. Basically, with a combination of the current traveling waves detected at the relay location due to fault and open switching operations with apparent impedance seen by relay, the remote breaker operation is detected and the faulted line is identified. The protection developed is selective and is not affected by power system oscillations. The system was simulated with the MICROTRAN, the results showing the feasibility of implementing this algorithm.