基于云模型的独立变桨距控制仿真研究

Research on Simulating Independent Variable Pitch Control System Based on Cloud Model

当风速高于额定风速时,风电机组需要进行变桨距控制,调节桨叶桨距角使输出功率稳定在额定功率附近。风速受风切效应和塔影效应的影响,在风轮旋转平面内的风速分布不均匀,因此统一变桨距控制得不到较好的控制效果。风力发电系统具有强非线性、时变不确定性等特点,模糊PID控制完成变桨距控制虽然可以很好地解决非线性问题,但模糊PID控制只着重模糊性,没有考虑到风速变化会带来的随机误差。在分析了风切效应、塔影效应对风速的影响和风电机组各参数之间的关系的基础上,提出基于云模型的独立变桨距控制系统。运用Matlab仿真软件和RT_LAB仿真实验平台对控制系统进行仿真,仿真结果表明输出功率恒定在额定功率附近,且超调小,稳定性强,取得较为理想的控制效果。

The wind turbine generator running at a speed above the rated wind speed asks for variable pitch control and a pitch angle adjusted to keep output power constant around the rated power .The wind speed influ-enced by both wind shear effect and shadow effect distributes uneven within rotor ’ s rotating plane , and a uni-form variable pitch control fails to bring good control effect .The wind turbine generator has strong nonlinearity and time-varying uncertainty , and the fuzzy PID control for the variable pitch control can solve nonlinear prob-lem well and considers little of the random error caused by the wind speed change because of its attention focu -sing on the fuzziness .Basing on analyzing the wind shear effect and shadow effect on wind speed and the rela-tionship between parameters of the wind turbine generator , the independent variable pitch control system based on cloud model was proposed .Simulating the system with Matlab and RT-LAB experiment platform shows that keeping output power constant around the rated power together with small overshoot and strong stability can bring ideal control effect .