An adaptive window length algorithm for accurate high speed digital distance protection

This paper describes the development of an adaptive window length algorithm for high speed digital distance protection. The sampling window length will be increased automatically from fault inception until the computed fault impedance stabilises. The final window length is adaptable to the severeness of the disturbance. The use of a moving average technique further improves performance. Extensive simulation results show that this algorithm possesses excellent performance for both strong and weak system configurations. Copyright (C) 1997 Elsevier Science Ltd.