The wind energy industry has grown very fast among the developed countries as it is remarkably clean and has a better quality in power system design. Consequently, with the increase of wind power applications in power systems, wind farms are needed for participation in network operations using efficient control strategies. This paper offers a comparative study on the performance of wind farm system equipped with doubly fed induction generators (DFIG) wind turbine. The study concentrates on the wind farm controller, which distributes power reference among wind turbines based on the demands of operator control system, while reducing their structural loads. The proposed controller is based on optimization technique in order to minimize the destructive fluctuation of torque and generator speed, in addition to supplying a satisfactory quality of power. The suggested wind farm control system has a hierarchical structure with both a central control level and a local control level. The performance of the control strategies is evaluated through simulations of wind farm controller equipped with DFIG wind turbines and proper results in solving the problem of both power and load optimizations are illustrated. (C) 2015 Elsevier Ltd. All rights reserved.