基于独立变桨的大型风电机组减载控制技术

Load Reduction Control Technology of Large-scale Wind Turbine Based on Individual Pitch Control

为了减小大型风电机组在运行过程中由于风剪切、塔影效应、湍流、偏航误差等因素引起的不均衡载荷,提出基于独立变桨的减载控制技术。通过传感器检测每个叶片的叶根载荷,利用Coleman坐标变换理论将叶根载荷变换为俯仰弯矩、偏航弯矩,经过两个PI控制器和Coleman反变换后,得到每个叶片桨距角的微调量,用以补偿风的不均匀引起的附加载荷。以5 MW风电机组为例,分别对集中变桨和独立变桨的控制技术进行对比仿真,结果表明,与集中变桨相比,独立变桨通过动态地调整每个叶片的桨距角,能明显减小由风切变、塔影效应和随机湍流等对风电机组造成的不平衡载荷,减小叶片轴承、偏航轴承、主轴、塔架等风电机组关键零部件的载荷。

In order to reduce the imbalance load of large wind turbine during operation due to factors such as wind shear, tower shadow, turbulence and yaw error, a load reduction control technology based on individual pitch control is proposed. Blade root loads measured by the sensor are converted into tilt moments and yaw moments by using theory of Coleman coordinate transformation. Tilt moments and yaw moments are controlled by using PI controllers. To compensate for the additional load caused by uneven wind, outputs of PI controllers are converted into fine-tuning pitch angle of blade by using Coleman inverse transformation. Collective pitch control technology and independent pitch control technology are compared for 5 MW wind turbine in this paper, the results show that： compared with collective pitch control technology, independent pitch control can reduce the imbalance load of wind turbine caused by wind shear, tower shadow effect and random turbulence through dynamic adjusting the pitch angle of each blade. Moreover, independent pitch control reduces loads of blade beatings, yaw bearings, main shaft, towers and other key parts of the wind turbine.