A Physical Constraint Based Active Support Strategy for Wind Farm

To cope with power grid inertia reduction due to large-scale grid-connection of wind farms and grid frequency secondary drop caused by single wind generator participating power grid frequency regulation, a station-level wind farm frequency regulation mode was proposed. Firstly, in the strategy design process a design principle not storing energy at wind turbine side was put forward to avoid the wind curtailment due to power grid frequency regulation. Secondly, a high-speed communication hardware platform for station-level control was designed and the boundary condition of physical constraint for frequency regulation of wind turbine generator was derived, meanwhile the objective function of station-level frequency control was established. Thirdly, a frequency modulation power restoration strategy based on constraint conditions for wind farm was formulated and the development of station-level frequency modulation controller under the condition of without wind curtailment was accomplished. Both experimental data and indicator analysis results show that the indices of power grid actively supported by the proposed station-level controller satisfy the requirements, and the risk of grid frequency secondary drop was obviously reduced by the active power provided by wind farm.