基于观测器的风力发电系统滑模变结构控制

Sliding-mode Control with Disturbance Observer for Adjustable-pitch Wind Power System

为了改进风力发电系统浆距角的控制性能,文中采用带观测器的滑模控制理论设计出了一种新型滑模控制器。该控制首先建立系统的数学模型,然后设计了常规滑模变结构控制器。为了减小控制抖振,设计基于观测器的滑模控制器,该控制包含两个观测器,其中一个用于估计风速波动信号的干扰,另一个用于观测当风速波动时引起的风轮转子转速波动干扰。该控制器与传统滑模控制器相比,不仅减小了系统的控制抖振,还使风力机在高于额定风速阶段的桨距角控制更具有稳定性能。最后通过仿真研究,证明了该设计方案的合理性和控制器的鲁棒性。

For the performance improvement of the adjustable-pitch control in wind power generation, a novel sliding- mode control is designed based on the sliding-mode control theory and the observer method in this paper. First, the system model is developed. Then the conventional sliding-mode controller is designed. On this basis, in order to smooth and steady the adjustable-pitch control, a novel sliding-mode control based on the observer method is pro- posed, which contains two disturbance observers. One of the observers is used to estimate the disturbance signal of the wind and the other one is used to observe the rotated disturbance signal of wind turbine for the effected wind. Compared with the traditional sliding-mode controller, the proposed controller not only can reduce the shudder of control system, but also make the adjustable-pitch control more reliable and safety when the wind speed is higher than the rated value. Finally, the simulation study verifies the rationality and robustness of this control scheme.