7 Sliding Mode Variable Structure Control Strategy Based on STATCOM in Wind Farm

STATCOM adjusts the reactive power in the transmission lines efficiently without the interference of power system voltage, playing an important role for improving the quality of grid power in large power wind farm. This paper analyses the dynamic mathematical model of STATCOM, and realize reactive power compensation of power wind farm by adopting sliding mode variable structure control theory. It's verified that the method for the transient voltage stability of wind power system is effective, by the simulation in the MATLAB. When the three-phase short circuit fault occurs in the wind Farm, comparing the PI control strategy, it is shown that the control strategy using sliding mode variable structure can help variable speed asynchronous generator recovery the machine voltage with good dynamic and static performance, meanwhile, the application of sliding mode control strategy can improve the power quality of wind farm and ensure the stability and safety of wind power system.