Mitigation of voltage unbalances and sags with phase-jumps in grid connected wind generation

In this paper, a new methodology is proposed to mitigate the unbalanced voltage sag with phase jumps and voltage unbalance in a grid connected doubly fed induction generator (DFIG) based wind generation system through a series converter (SC) connected between DFIG and the grid. For obtaining the minimum real power injection by SC of DFIG, an objective function is derived along with practical constraints like injected voltage limit on SC, phase jump mitigation and angle of voltage injection. Classical optimization has been used to find the solution of the objective function derived for minimizing real power injection of SC of DFIG along with the constraints. The proposed method has been validated through detailed simulation studies.