Modeling and Small Signal Analysis of a Grid Connected Doubly Fed Induction Generator

Abstract

Wind power, as an alternative to fossil fuels, is plentiful, renewable, widely distributed, clean, produces no greenhouse gas emissions during operation and uses little land. Unlike other sources of electricity that require fuel in processing plants, wind energy generates electricity through wind, which is free. So wind turbines might be used jointly with conventional generation system to contribute to the grid. But this practice can affect the stability of the conditions of the power system. Hence, we need to contemplate the power system stability conditions when DFIG power plant appended to it. This thesis describes the modeling and small signal analysis of a grid connected doubly-fed induction generator (DFIG). The model was developed from the basic flux linkage, voltage and torque equations. The change in properties for different system parameters, operating points, and grid strengths are computed and observed. The results offer a better understanding of the DFIG intrinsic dynamics, which can also be useful for control design and model justification.