Optimal Capacitor Placement and Rating for Large-Scale Utility Power Distribution Systems Employing Load-Tap-Changing Transformer Control

Significant opportunity for savings in energy and investment through improved performance of power distribution systems exists the optimal placement rating capacitors, a conventionally cost-effective popular reactive compensating technology. A novel capacitor planning (OCP) procedure is proposed large-scale utility systems, which exemplified on an existing circuit approximately 4,000 buses. An initial sensitivity analysis employed to intelligently reduce OCP computation time maintain quality configurations. Three optimization objectives are considered, including minimization total system active losses, standard deviation node voltages, rating. Eight multi-objective methods that employ non-dominated sorting algorithm III (NSGA-III) concept compared determine individual merits. Differences between include incorporation penalty constraint voltage violations automatic readjustment load-tap-changing (LTC) transformer tap settings re-configurations concurrently within optimizer, ensures peak fair comparison reference case. multi-step model conversion process was developed with OpenDSS enable be generally applicable real circuits. performed three example sub-circuits served by substation 48MW, 9Mvar load, represents most extreme case offers best savings. Example configurations from resulting Pareto sets pseudo-weight vector approach also analyzed systematic configuration types inform selection.