Multiobjective Tabu Search for service restoration in electric distribution networks

Contingency situations may cause emergency states in distribution systems; these states are denned as the interruption of power supply. The importance of the maintenance of the quality limits in relation frequency and duration of interruption means that such situations should be avoided whenever possible. The service restoration problem is designed to minimize the number of consumers affected by a fault, by transferring them to distribution support feeders, thus restoring power, but without violating electrical and operational conditions, such as radial network configuration, and equipment and voltage drop limits. This paper outlines a new method for the restoration of service which uses a multiobjective version of the well-known Tabu Search metaheuristic. Two criteria are considered: the minimization of the load not restored and of the number of switching operations involved. The flexibility and effectiveness of the proposed method are proved in a practical test system.