Type-3 Wind Turbine Generators

The type-3 wind turbine generator model can be built with the doubly fed induction generators (DFIG) and is shown in Fig. 1. The DFIG is a machine that comes with AC excitation. The AC excitation (variable magnitude and frequency) is applied to the rotor, and it is provided by the power converters. The power converters are rated for 33% of the rated power of wind turbines and it provides the facility of variable speed in the range of ±33% with synchronous speed (Ns).