Reactive power planning and its cost allocation for distribution systems with distributed generation

This paper addresses some of the modeling and economic issues pertaining to the optimal reactive power planning of radial distribution systems with distributed generation. When wind power generation (WPG) units are installed in a distribution system, they may cause reverse power flows and voltage variations due to the random-like outputs of wind turbines. To solve this problem, we introduce static VAr compensator (SVC) into distribution systems, and combine the reactive power support from distributed diesel units for voltage control. An optimal reactive power planning model is proposed in this paper. Monte-Carlo simulation is used to simulate the uncertainty of wind power generation. The locations and the outputs of SVCs and distributed diesel units are determined using our proposed optimal reactive power planning model. Genetic algorithm (GA) is used to solve the optimization problem. Furthermore, we apply the Shapley value axiom in cooperative game theory to allocate the reactive power cost of SVC among wind power turbines, which have caused voltage variations. Finally, we discuss the allocation results from an economic point of view