Doubly Fed Induction Generator for Wind Energy Conversion Systems With Integrated Active Filter Capabilities

This paper deals with the operation of doubly fed induction generator (DFIG) with an integrated active filter capabilities using grid-side converter (GSC). The main contribution of this work lies in the control of GSC for supplying harmonics in addition to its slip power transfer. The rotor-side converter (RSC) is used for attaining maximum power extraction and to supply required reactive power to DFIG. This wind energy conversion system (WECS) works as a static compensator (STATCOM) for supplying harmonics even when the wind turbine is in shutdown condition. Control algorithms of both GSC and RSC are presented in detail. The proposed DFIG-based WECS is simulated using MATLAB/Simulink. A prototype of the proposed DFIG-based WECS is developed using a digital signal processor (DSP). Simulated results are validated with test results of the developed DFIG for different practical conditions, such as variable wind speed and unbalanced/single phase loads.