Improvement of power quality and dynamic voltage of wind farms using an inductive filtering method

Unlike the traditional reactive power compensation and ac passive filtering method for the wind farm, this paper presents a new approach of a static synchronous compensator (STATCOM) and related fully-tuned (FT) branches based on an inductive filtering method for a wind farm equipped with double fed induction generators (DFIGs). First, the main circuit topology of a new wind power integrated system is presented. Then, the mathematical model is established to reveal the reactive compensation and harmonic suppressing performance of the new grid-connected transformer. The control strategy of STATCOM is introduced briefly in this paper. Simulation studies are carried out in the Digsilent/Powerfactory to illustrate the performance of the new grid connected wind power system. The results indicate that the new approach can not only enhance the low-voltage ride-through capability of wind turbines, but also significantly prevent harmonic components flowing into the primary (grid) winding of the new grid connected transformer. Besides, since the new method can compensate reactive power near the grid, the wind farm has a better dynamic stability.