Wind turbine generator system based on Cascaded Doubly Fed Induction Generator

Doubly Fed Induction Generators (DFIG) have many industrial applications and are also used as Wind Power generators. The brushes, required to connect the energy supply to the rotor, are the main drawback of these machines. Therefore, it is interesting to replace this generator by the so called Brushless Doubly Fed Induction Generator (BDFIG). The Cascaded Doubly Fed Induction Generator (CDFIG) can be used as a starting point in the study of the BDFIG. This paper presents a study of a variable speed wind energy conversion system based on active and reactive power control of a CDFIG with Maximum Power Point Tracking (MPPT). The vector control is divided in two parts: current control loop and power control loop. The vector control and the power flow are verified by experiments and the results indicate the advantages of using the CDFIG as a variable speed generator.