Optimum Size and Location of Shunt Capacitors on Distribution Feeders

Abstract

The reactive power flow in utility systems produces losses which utility engineers try to keep at a minimum with the installation of capacitor banks. Load flow studies usually furnish a good indication of where they will render maximum benefit. In many instances, they can be installed on primary feeders. A study is made of the optimum location, size, and timing of capacitor banks on feeders with uniformly distributed loads and randomly distributed variable spot loads to evaluate the reduction in costs of active and reactive losses where voltage regulation is no problem. A new simplifying principle is established, taking moments of the loads with respect to feeder resistances or reactances. The equations developed can be used in preparing computer programs for capacitor applications.