HIDDEN FAILURE RISK ASSESSMENT AND ON-LINE ADAPTIVE RELAY COORDINATION BASED ON RISK MINIMIZATION

摘要

Based on on-line risk assessment, hidden failures caused by relay setting miscoordination are studied in this paper. Regions of vulnerability for miscoordination are calculated by an on-line point-by-point fault simulation program. Condition probability for relay miscoordination is calculated by event tree method and relay miscoordination risk is obtained. The influence of the relay miscoordination on power system security can be evaluated quantitatively and the critical relay with a major impact on power system security is identified. Relay setting is on-line coordinated. Minimum break point set (MBPS) is solved through a linear 0-1 integer programming program. Based on risk minimization, relay setting is on-line adaptively coordinated. Miscoordination risk of a relay can be decreased and the critical relays can be eliminated. Numerical experiments on some real power networks in China were done and the result validates the methods proposed in this paper.