Optimal VAR control in grid-integrated DFIG-based wind farm using swarm intelligence

Wind farms (WFs) based on doubly-fed induction generator (DFIG) have become nowadays very popular for the national grid integration option. The reason for this is their ability to support the electric grid with its reactive power. Most of the optimal reactive power (VAR) problems in the past, have dealt with conventional electric grid, and a few with the grid-connected WFs based on squirrel cage induction generator (SCIG). This paper presents an optimal VAR control problem where all VAR control variables present in the network as well as the reactive power from the reactive power capability (RPC) of DFIGs are optimized for achieving the system active power loss minimization. Particle swarm optimization (PSO) algorithm is used as an optimizer tool. Simulation results based on IEEE 6-bus test system show the effectiveness of the optimal use of RPC of DFIGs in solving VAR problem.