Wind Power Active Power Control Strategy Research

With more and more wind-generated power integrated in the grid, not only does it become more and more difficult to maintain a steady power supply, but also the intermittent and volatile nature of wind-power becomes a significant threat to the stability and security of the power grid. Active power control for wind farms by centralized allocation of each individual wind turbine leads to the increasing of output power quality of wind farms, and the reduction of adverse influence caused by wind-generated power. Active power control for wind turbines makes wind turbines rapidly tracking power setpoints in the presence of interference. Therefore, active power control plays a key role in wind power generation system.In order to solve the problem of active power control in wind power generation system, to improve the output stability of the system and to reduce the interference and mechanical loss of wind turbines, the main achievements are listed as follows.1. Principle of active power control for wind farms and wind turbines have been analyzed. The basic structure and the communication protocols of the wind farm are studied. And the strategy of active power control for wind farms based on ultra-short-term power forecast is then proposed. Active power control strategy for wind turbine has been researched based on the operational characteristics of the wind turbine.2. A multi-objective optimization method is introduced to the active power control of wind farms in this paper. An active power allocation method for wind farms based on goal programming has been presented. By taking multi objectives and requirements in wind power control into account, the active power allocation problem is formulated as a multi-objective optimization problem.3. Basic model and control algorithm of the wind turbine are analyzed. In order to deal with the interferences of the wind turbine during operation, interference suppression methods are proposed to optimize the output power of wind turbines. Based on the above works, the simulation of the active power control base on the multi-objective optimization model has been completed, and comparisons between the proposed strategy and average allocation strategy has been made. The proposed method guarantees the maximum number of running at power rising and minimum number of stopping at power declining respectively, while the control effect is much better than average algorithm. Then, the simulation of the proposed interference suppression methods has been completed, and a comparison between the results and the basic model of wind turbine has been made. The simulation results show that with the introductio of the interference suppression methods, the pitch angle output of the wind turbine is more smoothly. Moreover, mean square errors and maximum overshoots of the output power, output torque and output motor speed decrease obviously.