Online intelligent verification of relay protection based on protection importance

With the rapid development of national economic and social needs in our country, power grid has gradually developed to modern interconnected power system with flexible operation mode, and which increasingly high demands on relay protection system. In order to enable the verification and management of relay protection setting more scientific and effective, an online intelligent verification of relay protection based on protection importance is presented. First, combining risk assessment theory with grid cascading failure risks, obtain system comprehensive risk and use it to measure the importance of all protections. Then, verify all protection settings based on protection importance from high to low order online. The simulation of IEEE39-bus system and the analysis of the algorithm complexity prove the method feasible and correct, which avoids the shortage of traditional setting checking randomly, and is of great significance to improve the security and stability of power system.