Reliability Research And Analysis Of Power System Digital Relay Protection Device

The development of modern power system lead to the configuration of systembecome more and more complicated and the scope become more and more huge.Therefore, the feasibility of complicated failure become more and more great. Andthat the running reliability of the protective relay system in power system is close tothe he running reliability of power system. Especially the incorrect action of theprotective relay system not only bring on the failure of power system enlarge, but alsothe ill chain-reacting is likely to happen to break the power system down, which canlead to power cut on large area, may result in great economy loss, may have seriouseffect on the live of the people. The people have found that the study of the runningsecurity and reliability had play an very important part in power systems, and it isurgent to improve the operated capability of the protective relay and do research insystem protection.The definition and calculation of operative reliabilit y indices of protectiverelay in power s ystem protection are closel y related to the calculation ofreliabilit y indices of power s ystem and the assessment, application,improvement and development of protective relaying units. It is a key link todetermine the intension of operative state (i. e, the definition of correct actionand incorrect action) of protective relay.In this paper, reliabilit y evaluation is discussed b y one classical method inpower s ystem: Monte Carlo simulation and the reliabilit y equivalent model isinvestigated respectivel y in detail. One protective relay’s reliabilit y parametersare calculated using a MATLAB software and doing anal yze in its reliabilit y.Base on it, the whole protective relay s ystems’ reliabilit y is evaluated.