Based on the wind farm output forecasting and local electric network reactive power optimization results， the wind turbines electric control parameters are calculated as inputs to the reactive power controller. A reactive power regulation method based on application integration is proposed. The processes of power forecasting and parameter setting in the wind farm supervisory control and data acquisition（SCADA） system are discussed. The doubly fed induction generator（DFIG） wind turbine is used as an example to show how to adjust reactive power.