Changes

For variable-speed systems with limited variable-speed range, e.g. ±30% of synchronous speed, the Doubly-fed Induction Generator(DFIG) can be an interesting solution.This is mainly due to the fact that the power electronic converter only has to handle a fraction (20-30%) of the total power as the converters are connected to the rotor and not to the stator. There- fore, the losses in the power electronic converter can be reduced, compared to a system where the converter has to handle the total power.The overall structure of wind power generation through DFIG as shown in the figure below.