Power Oscillation Suppression by Improved Control Strategy for DFIG-Based Wind Turbine

Wind turbines (WTs) play an important role in modern power system. However, in WTs, fluctuations caused by equivalent wind speed pulsation can propagate to the grid, thereby degrading the power system performance. The propagation characteristics of pulsating power has been rarely investigated and in most cases it is analyzed by means of simulation rather than quantitative methods. Hence, this paper proposes a fluctuation suppression strategy for doubly-fed induction generator (DFIG)based WT system, reducing the negative impact on electric grids. The detailed model of the multi-field WT system is derived to achieve the quantitative analysis of oscillation propagation and suppression characteristics. The effectiveness and correctness of the strategy are verified by theoretical analyses, as well as PLECS and OPAL-RT 5707 based results.