Service restoration in modern distribution systems addressing grid-connected and islanded operations

Abstract In modern Distribution Systems (DSs), multiple decentralized generators can be connected to the network and, in some scenarios, can operate isolated from the substation. The island operation affects the Service Restoration (SR) process and may benefit the Distribution Companies (DICOs). However, most of the studies involving SR take into account only the system’s static behavior, ignoring the transient characteristics. While these studies have been validated for decades on classic passive DSs, they cannot be extended for SR with load insertion into islands. This paper studies the dynamic aspects of the SR process, verifying the protective devices’ performance due to the island’s formation and operation, and loads reconnection through Distributed Generators (DGs). Based on the test results for a 405-bus DS, the paper points out the possibility of infeasible SR plans due to disregarding the transient behavior of DGs. The paper also proposes a novel set of constraints that aggregates practical dynamic and static aspects for the SR problem. Finally, a computationally efficient Multi-Objective Evolutionary Algorithm (MOEA) based on subpopulation tables is employed to solve the SR problem considering the newly proposed constraints.