A technique for generating computer models of microprocessor-based relays

This paper describes a unified approach for the computer simulation of microprocessor-based power system relays so that their performance can be evaluated for a variety of situations without using the relay. The modeling philosophy and its implementation are described. The proposed technique was applied to produce computer models of a distance relay, a differential relay and an overcurrent relay. These models were then used for testing the relays´ performance for a variety of situations. Results obtained from the overcurrent relay model are presented