Modeling and control of induction generator applied to variable speed Wind Energy Systems Conversion

This paper presents study of a Wind Energy Conversion System (WECS) based on asynchronous machine connected to a power grid through a back to back converter. The power output of a WECS fluctuates with the wind velocity, which makes it difficult to analyze and control. The control objectives of generator side converter (GSC) are to optimize the energy capture from the wind turbine. The grid connected converter delivering the energy from the machine side to the utility grid regulated the DC link voltage and the power flows to the grid. We develop an approach to control the electrical and mechanical variables. This approach is based on the PI control of DC link voltage, pitch control of the wind turbine and a hysteresis control for the grid side converter. The effects of a voltage dip on different variables of the network are analyzed and the system´s performance is presented. The complete control system has been analyzed and validated by Matlab simulation.