Variable Speed Wind Generator Associated with Hybrid Energy Storage System-Application for Micro-grids

With the depletion of fossil resources and problems of climatic changes, the use of renewable energy is suitable to ensure the sustainable development. In this paper, a doubly fed induction generator (DFIG) driven by a wind turbine is associated with a hybrid energy storage system. The DFIG is controlled with a flexible algorithm based on fuzzy logic control combined with direct torque and reactive power control (DTRPC). The objective is to analyze the performances of the DTRPC taking into account the randomness of wind allowing the three modes (Sub, Super and synchronous) operations, in successive and continuous manner, with a particular focus on synchronous mode. Battery (BESS) and supercapacitor (SCESS) hybrid system constitute the energy storage part. The supercapacitor is used to support the battery operations in rapid current load variations and its model is based on the experimental data results obtained in the previous works. The power management algorithm of the whole system is developed to reduce the battery depth of discharge, to investigate the effect of wind speed fluctuations and to ensure smooth power output from the wind turbine generator and the required load power. The simulation results which are presented and analysed below are performed using Matlab/Simulink.