A Two-Stage Performance Optimization-Based Microgrid Formation in Distribution Networks With Distributed Generations

Microgrids are fundamental building blocks of smart grids. With increasing penetration of renewable energy-based distributed generation (DG) in distribution systems, microgrid formation is an effective way to improve reliability and resiliency by transforming a conventional distribution network into its active form. In this article, a new microgrid planning method through optimal microgrid formation in distribution networks is proposed through a two-stage performance optimization: in Stage 1, the total power losses, the adequacy and reliability of the whole system are optimized; in Stage 2, isolating switches are optimally allocated at judicious locations to improve the reliability of the system. Brute Force search algorithm and Backward Forward sweep method are used to solve the optimization and load flow problems, respectively. Case studies are conducted using the IEEE 33-node test system and a real 404-node distribution system to validate the proposed method.