Automatic restoration in distribution systems considering DG transfer and islanded microgrids

This paper proposes a new centralized control scheme for automatic back-feed service restoration in distribution systems with high penetration of distributed generation (DG). The proposed restoration algorithm introduces three types of power transfer between the tied adjacent feeders during the restoration process: load transfer, DG transfer and a combination of load/DG transfer. Another feature of the proposed scheme is the ability of forming islanded microgrids (IMGs) in the post-restoration network by utilizing the available DGs. The objectives of the proposed algorithm are to minimize 1) the unserved loads, and 2) the switching operations, taking into consideration the load variability during the fault occurrence and the system operational constraints. Several case studies have been carried out on a typical distribution system with multiple feeders to show the effectiveness and robustness of the proposed algorithm.