Development of Reliability Analysis System for Protective Relays

Abstract

It is expected that the introduction of the competition policy would bring us cheaper electricity. The effective use of protective equipment and the rationalization of the maintenance procedure are needed. To realize them, a reliability analysis system for protective relays has been expected. Conventional systems or methods didn't enable us to analyze the annual change of the reliability nor the reliability when maintenance procedure would be changed.
The Reliability Analysis System for protective relays (RASPR) developed satisfies the above requirements and solves the problems. The RASPR consists of two databases and reliability analysis part. The RASPR realizes to analyze the annual change of the reliability in combination with two databases and to analyze the influence on the index of the reliability according to the change of transition parameters. The construction method of an arbitrary transition diagram enables us to analyze the reliability under any maintenance procedure or for any type of protective relays.
This paper describes the features of the RASPR, the construction method of an arbitrary transition diagram, and finally some examples of the reliability analysis. The RASPR is in operation at all electric power companies in Japan.