基于方位角和载荷联合反馈的独立变桨距控制策略研究

Study of Individual Pitch Control Based on Azimuth Angle and Load Feedback

针对风切变和塔影效应引起的风力机气动载荷周期性波动,展开风电机组独立变桨距控制策略研究。基于叶素动量理论进行风轮叶片气动建模,在Matlab/Simulink平台上编程实现叶片气动载荷计算模型,并与GH Bladed仿真结果进行对比分析。提出了基于方位角和载荷联合反馈的独立变桨距控制策略,根据方位角反馈设置动态权系数,周期性调节每支叶片的桨距角,并在此基础上增加了叶根挥舞载荷PID控制环节,以微调修正桨距角。基于Matlab/Simulink和GH Bladed平台进行仿真分析,结果表明,该联合反馈控制策略可有效平缓周期或随机性的叶片挥舞载荷波动,而且对于减小风轮不平衡载荷以及降低风力机疲劳载荷有较好的效果。

Considering the periodic load fluctuations of wind turbine caused by wind shear and tower shadow, individual pitch control was studied in this paper. Based on blade element momentum （BEM） theory, the blade aerodynamic characteristic was modeled on Matlab/Simulink platform and calculation results were compared with the simulation results on GH Bladed software. The individual pitch control based on azimuth angle and load feedback was proposed in this paper. With azimuth angle feedback, the dynamic weight coefficient was set and the pitch angle of each blade was periodically adjusted. On this basis, the blade root flapwise load PID controller was superimposed to provide the fine tune value and correct the pitch angle of each blade. Then the proposed individual pitch control strategy was verified on Matlab/Simulink and GH Bladed platform and simulation results show that it can significantly alleviate both the periodic and random blade flapwise load fluctuations, which means the strategy holds good potential to reduce rotor unbalance loads and mitigate fatigue loads of wind turbine.