Impact of distributed generation on volt/Var control in distribution networks

As power system in many countries is going to be restructured and deregulated. After deregulation, because of numerous advantageous of distributed generation (DG), the number of this kind of generators are going to be increased. DGs can affect entire system and especially distribution networks. One of the important control schemes at distribution system that DGs can change it is volt/Var control. This paper presents an efficient approach for volt/Var control in radial distribution networks takes DGs performance into consideration. In general distributed generations can be considered as PV or PQ nodes. In this paper DGs are modeled as PV nodes. The goal of this approach is to minimize power losses at distribution system through controlling the tap of load tap changer (LTC), size of substation capacitor, local controller settings and voltage amplitude of DGs. DGs, voltage regulators, local controllers, and load tap changer (LTC) are modeled completely and the optimization problem has been solved by using genetic algorithm. Finally the method is tested on IEEE 34 bus radial distribution feeders.