Grid Interfacing of Three-Phase Isolated-Winding Alternator Based WECS by Cascaded Multilevel Inverter

Recent power crisis has created an urge for setting up of alternative electricity generating systems preferably based on renewable sources such as solar and wind energy. Solar based generating units are functioning satisfactorily in low and medium power ranges. While reliable harnessing wind power is still an area of concern and needs cost optimal measures to make them more reliable. Thus this paper presents issues relating grid interfacing of wind energy conversion system based on a cascaded H-bridge multilevel inverter (CHBMLI) topology. The CHBMLI has been used as a VSI and operated in a current control mode in order to achieve the objectives of real power injection, load compensation, power factor correction, and harmonic compensation based on the proposed reference-generation scheme. The bonuses offered by CHB's are equal distribution of switching stress and power-losses, reduction in their power ratings, and high quality of inverter output. The closed-loop performance of the VSI adequately achieves the control objectives, i.e., grid interface of wind energy resource in addition to load compensation. The simulation studies were performed by using matlab© simulink® package.