819 / 2019-04-29 18:43:19

A Novel Method for Health Level Evaluation of Relay Protection

Analytic Hierarchy Process (AHP),evaluation index system,health level,relay protection

As the guardian of the power system, relay protection is the first line of defense to ensure the security of power grid.
In recent years, a series of the large blackouts happen in the large-scale power systems with interconnection shows that the blackouts are often associated with incorrect actions of the relay protection equipments, in particular, the relay protection defects may lead to mis-operation of the relay and deteriorate the event of a blackout. The above phenomenon has attraction a lot of attention to the health level of the protection device increasingly. Therefore, it is of great significance to evaluate the health level of protection equipment comprehensively and objectively.
Establishing a scientific and reasonable evaluation index system is the first step to achieve the purpose of evaluation. Considering that the health level of relay protection is closely related to its operation and maintenance, the evaluation target of relay protection health level is decomposed into three comprehensive evaluation factors: function realization ability, equipment reliability and maintenance efficiency. After that, eighteen basic evaluation indicators serving various comprehensive evaluation factors are selected to complete the establishment of the health level evaluation index system of relay protection. After completing the establishment of the evaluation index system, this paper uses the improved Analytic Hierarchy Process (AHP) to calculate the weight of evaluation indicators. Finally, the effectiveness of the evaluation method is verified by the relay protection equipment with different voltage levels, and the suggestions for improving the health level of relay protection are proposed.