Abstract: Aiming at the problem of reactive power control lag and poor voltage command following in single time section prediction information of wind farm, a reactive power and voltage control strategy of doubly fed wind farm based on model predictive control is proposed. The strategy aims at minimizing the deviation between the grid-connected point voltage and the terminal voltage of the wind farm. Firstly, the reactive power equipment output and load demand prediction information are calculated based on the time scale, and the reactive power voltage prediction control model is established. Secondly, more detailed prediction control points are divided in the control cycle, the prediction model is modified, and the dual system control instructions are coordinated and distributed in advance to effectively reduce the reaction time. When the wind speed fluctuates rapidly, the voltage control performance can be optimized and the tracking accuracy can be improved, so that the reactive power equipment can quickly compensate the reactive power to stabilize the voltage of the grid-connected point, and the dynamic reactive power capacity of the static var generator can be reasonably regulated to maximize the reactive power reserve. A doubly-fed wind farm model is established in MATLAB / Simulink for simulation. The results show that the proposed strategy can quickly coordinate the output of reactive power equipment, effectively reduce the reaction time, and enhance the rapid adjustment ability of reactive power in wind farms.

Key words: double-fed wind farm, voltage fluctuation, model predictive control, fast optimization strategy, reactive voltage control