An autonomous wind energy conversion system with permanent magnet synchronous generator

This paper deals with a permanent magnet synchronous generator (PMSG) based variable speed autonomous wind energy conversion system (AWECS). Back-back connected voltage source converter (VSC) and a voltage source inverter (VSI) with a battery energy storage system (BESS) at the intermediate dc link are used to realize the voltage and frequency controller (VFC). The BESS is used for load leveling and to ensure the reliability of the supply to consumers connected at load bus under change in wind speed. The generator-side converter operated in vector control mode for achieving maximum power point tracking (MPPT) and to achieve unity power factor operation at PMSG terminals. The load-side converter is operated to regulate amplitude of the load voltage and frequency under change in load conditions. The three-phase four wire consumer loads are fed with a non-isolated star-delta transformer connected at the load bus to provide stable neutral terminal. The proposed AWECS is modeled, design and simulated using MATLAB R2007b simulink with its sim power system toolbox and discrete step solver.