Design of DMLHFLC (dual mode linguistic hedge fuzzy logic controller) for an isolated wind diesel hybrid power system with BES (battery energy storage) unit is proposed in this paper. The design methodology is a hybrid model based on the concepts of linguistic hedges and hybrid genetic algorithm-simulated annealing algorithms. Dual-mode concept is also incorporated in this proposed controller because it can improve the system performance. The system is simulated and the results are compared with proportional plus integral controller and FLC (fuzzy logic controller). Sensitivity analysis and robustness of the controller is tested. The results prove the effectiveness of the proposed controller. (C) 2010 Elsevier Ltd. All rights reserved.