Optimal volt/var control in distribution systems

A new approach to optimal reactive power and voltage control in radial distribution systems is proposed in this paper. The optimal control is to rind a proper dispatch schedule for shunt capacitor banks and on-load tap changer at substation and shunt capacitor banks on feeders so that the power loss is minimized and the voltage profile is improved. To reduce computation burden, the whole control is decomposed into two sub-problems, namely sub-problem on substation level and sub-problem on feeder level. A simplified dynamic programming and a fuzzy logic control algorithm are used to deal with the two sub-problems, respectively. Coordination of the two algorithms provides an appropriate solution to the whole control problem. The numerical results demonstrate that the proposed approach is effective and feasible. (C) 2002 Elsevier Science Ltd. All rights reserved.