基于模糊LQR的Spar型海上浮式风力机载荷抑制

LOAD SUPPRESSION OF SPAR-TYPES OFFSHORE FLOATING WIND TURBINE BASED ON FUZZY LQR

针对复杂环境变化易引起海上浮式风力机不稳定的问题,提出一种基于模糊LQR、模糊PI相结合且易于工程应用的桨距控制新方案,实现维持浮式风力发电机组输出功率稳定、抑制浮台运动、减少叶根及塔基疲劳载荷的目的。模糊PI根据发电机转子转速误差变化动态选择期望的PI增益,模糊LQR基于模糊规则自适应调整闭环反馈增益,在保证风力机输出功率和浮台稳定的基础上,进一步减小叶根和塔基疲劳载荷。基于FAST与Matlab/Simulink在不同环境条件下进行联合仿真,验证所提方案的有效性和优越性;通过时域、频域分析表明,与PI控制相比,所提方案在减少叶根处平面外载荷和塔基横向载荷方面有明显改善效果。

Complex environmental changes are prone to cause instability of floating offshore wind turbines.A new pitch control scheme which is easy for engineering application is proposed based on fuzzy LQR and fuzzy PI to maintain the output power stabilization of the floating wind turbine,restrain the movement of the floating platform,and reduce the fatigue load of the blade root and tower foundation.The fuzzy PI dynamically selects the desired PI gain according to the variation of the generator rotor speed error.The fuzzy LQR adaptively adjusts the closed-loop feedback gain based on fuzzy rules to further reduce the fatigue load of blade root and tower while ensuring the output power of wind turbine and the stability of floating platform.Co-simulation is executed based on FAST and Matlab/Simulink to verify the effectiveness and superiority of the proposed scheme under different environmental conditions.The time and frequency domain analysis show that the proposed scheme has a significant improvement in reducing the out-of-plane load at the blade root and the lateral load at the tower base compared with PI control.