Maximizing service restoration in reliability optimization of radial distribution systems

Reliability optimization determines the optimal locations of reclosers, fuses, normally-closed switches, and tie lines in a distribution system. In quantifying the benefits that can be derived from customer restoration though tie lines, previous methodologies used predefined rules and did not maximize the service restoration that can be achieved. In this paper, we optimized distribution system reliability by dividing the reliability optimization problem into two parts: a main problem to determine the optimal locations of the devices and a sub-problem to maximize the service restoration through tie lines when evaluating a candidate solution to the main problem. In maximizing service restoration, we considered the voltage and loading constraints of the distribution system. We used Genetic Algorithm for both the main and sub-problems. To evaluate the performance of the methodology, we included optimization results for two simple radial distribution systems with voltage and loading constraints. Evaluation results allow extensions of the study in future work.