Reactive Power and Voltage Control Strategy for Wind Farm Based on STATCOM

The doubly fed induction generator (DFIG)'s reactive power output changes and fluctuates with active power output variation. Further,when its active power output in a certain extent,it begins absorbing reactive power. At this point,based on the variety relation analysis between active power and reactive power for DFIG,by introducing static synchronous compensator (STATCOM) in the wind farm,a reactive power control strategy which can restrain fluctuation of reactive power and guarantee effectively active power output of wind farm was proposed. Then a real time control system (RTCS) was built up. This RTCS not only has advantages as flexible operation mode and rapid reactive power response,but also can help to enlarge operation range of wind farm reactive power,to improve the regulation quality of reactive power and voltage level of point of common coupling (PCC) as well as power grid. Thus the problems,such as fluctuation of DFIG reactive power output,and drawing reactive power under a certain condition,can be solved. The simulation of a practical example shows that the control strategy is effective and feasible.