An Novel Active Power Control Method Of Wind Farm

Nowadays energy and environmental problems are outstanding. The excessive consumption of fossil energy, not only causes the depletion of resources, but also has brought serious pollution to the global environment. Wind energy is a kind of renewable energy, which has great development value and mature technologies, and has been paid more and more attention. However, with the increase of wind power penetrating on power systems, the nature of randomness, intermittency and fluctuation of wind power becomes one of major factors impacting the stability and safety of the power grid. Therefore, it is thus critical to design advanced dispatching strategies such that the power of wind farm satisfies the stability and quality requirements of the power grid, as conventional power plant. The main work of this thesis is to study the active power control method of wind farm. In order to study the active power control method of wind farm, this thesis mainly carried out the following work.In this thesis, the models of wind speed, wind turbine and wind turbine’s generator are established. The method of constant active power control is proposed. The rotor speed tracking controllers based on torque control and current control are designed by using the robust adaptive method. The stability of the controllers is proved by Lyapunov function. The effectiveness of the algorithm is verified by MATLAB simulation.To research the active power control method of wind farm, the basic model of wind farm is established. Then based on the short-term forecasting of wind power, and according to the command value and the actual value of the active power, different control strategies are adopted. Furthermore, an optimal allocation model of the active power for wind farm is created by minimizing the error produced by the active power output of wind farm and the power demand, which also minimizes the start/stop counts of wind turbines. The optimization problem is solved by using genetic algorithm. Finally, the effectiveness of the proposed control strategy is validated by simulation, and compared with the conventional control method, this method not only makes active power of wind farm track the power command value more effectively, also can effectively avoid the mechanical loss caused by the otiose start/stop of wind turbine. Thereby the proposed method is obviously superior to the conventional control method.