A Grid Connected Open-End Winding Induction Generator System With Series Compensation

This article presents a new grid connected induction generator (IG) system having open-end stator windings with a series reactive power compensator. The proposed scheme consists of a two-level capacitor fed voltage source inverter (VSI) connected to one side of the stator windings of the IG while the other ends of the windings are directly connected to the grid. A current phasor oriented rotating reference frame based control scheme is developed to control the operation of the VSI to ensure that it compensates the reactive power required by the IG. Thus, the IG system can supply active power to the grid without drawing reactive power from it for excitation. Unlike the shunt compensated IG systems, the proposed scheme does not require an interfacing inductor for connecting to the grid thereby reducing the hardware footprint. The proposed scheme is validated by simulation using PLECS software and the simulation results are presented in the article. A prototype of the system was developed in the laboratory to experimentally verify the proposed scheme and the experimental results are also presented in this article.