An Adaptive Distance Relay and Its Performance Comparison with a Fixed Data Window Distance Relay

This paper describes the design, implementation, and testing of an adaptive distance relay. The relay uses a fault detector to determine the inception of a fault and then, uses data windows of appropriate length for estimating phasors and seen impedances. Hardware and software of the proposed adaptive relay are described in the paper. The relay was tested using a model power system and a real-time playback simulator. Performance of the relay was compared with a fixed data window distance relay. Some results are reported in the paper. The results indicate that the adaptive distance relay provides faster tripping in comparison to the fixed data window distance relay.