DEVELOPMENT IN MULTI-INPUT PHASE AND AMPLITUDE COMPARATORS AND THEIR APPLICATIONS TO OBTAIN NEW DISTANCE RELAY CHARACTERISTICS

Abstract

Two input comparator circuits were used in mot of the power system protection schemes. The development of phase comparators made it possible to construct static relays for distance protection with new type of character-istics like a quadrilateral and composite polar character- istics. Some of the theoretical developments in 2-input and multi input phase and amplitude comparators are reviewed here. This dissertation is an attempt to investigate into the theoretical and experimental require-ments needed to obtain a particular composite polar characteristic. This type of characteristic is useful for high voltage long transmission lines where the possi-bility of power swings and overload is more. In this static distance relay the input phase comparators with unsymmetrical angular limits are combined logically to get the required composite polar characteristic.