Fast Security Analysis for Urban Power System Based on Full Voltage Level Security Region

The security verification of distribution network is of great significance for the planning and operation of distribution network. The security region has higher advantages than the traditional N-1 check. Because the existing security region method only considers the medium voltage distribution system, this paper proposes a full voltage level distribution network security region model. Firstly, the definition of full voltage level security region and simulation verification method are introduced; secondly, the security region and security boundary models of three-level network and four-level network are established respectively; finally, the security region boundary is calculated and analyzed for an actual example, and the simulation image is compared with the theoretical image to verify the effectiveness of the method.