A D-S evidence theory-based relay protection system hidden failures detection method in smart grid

摘要

Hidden failures in relay protection systems are the primary factors for triggering the cascading outages and bulk blackouts of power systems, but it is difficult to detect these when power systems operate normally. In smart grids, relay protection management information systems allow us to obtain many sequence of event records under disturbances and faulty conditions. By studying such record information, this paper proposes a detection method for hidden failures based on the features of relay protection systems. In this method, certain evidence is constructed by analysis of redundancy and coordination between the primary and backup protections or within the backup protection. Meanwhile, uncertain evidence is constructed by utilizing the fault location. Then, by combining all the evidence with D-S evidence theory, detection criteria for detecting hidden failures in relay protection systems are presented. Last, the effectiveness of the proposed algorithm is verified on the IEEE 39 bus system case. The results indicate that this method can detect hidden failures in relay protection systems and send alarm information. Thus, it is of great importance to ensure the security operation of power systems in smart grids.