基于ICPSO-PID风电机组桨距控制分析

Wind turbine pitch control using ICPSO-PID algorithm

针对传统的一阶变桨距机构简化模型难以描述真实的变距执行系统动态特性,建立了完整的电液变桨距风力发电机组高阶数学模型;根据风电机组额定风速以上恒功率控制目标并考虑变桨机构具有惯性和延迟特性,设计了基于功率和风速前馈的变桨控制器;针对额定风速以上变桨控制器参数整定难的问题,提出了一种基于改进协同粒子群优化算法(ICPSO)与比例、积分、微分控制器(PID)相结合的ICPSO-PID控制算法,并将其应用于桨距角PID控制器的参数整定.研究结果表明:提出的优化算法能够快速整定桨距角控制器的参数,风速前馈控制器能够提高变桨系统的动态性,功率控制环节能够实现额定风速以上风电机组恒功率控制.与传统PID控制器的控制效果相比,提出的控制方法具有超调量小、调节时间短和鲁棒性好等优良的控制品质.文中研究方法可应用到实际的电液变桨距风力发电机组控制系统中.

For the traditional simplified first-order pitch-control system model,it is difficult to describe a real dynamic characteristic of a variable pitch action system,thus a complete high order mathematical model has to be developed for the pitch control of wind turbine generation(WTG). In the paper,a pitch controller was designed based on power and wind speed and by considering the inertia and delay characteristics of a pitch-control system to achieve a constant power output when a wind speed was beyond the rated one. A novel ICPSO-PID control algorithm was proposed based on a combination of improved cooperative particle swarm optimization(ICPSO)and PID,subsequently,it was used to tune the pitch controller parameters; thus the difficulty in PID tuning was removed when a wind speed was above the rated speed. It was indicated that the proposed optimization algorithm can tune the pitch controller parameters quickly;and the feed-forward controller for wind speed can improve dynamics of a pitch-control system;additionally the power controller can allow a wind turbine to have a constant power output as a wind speed is over the rated one. Compared with a conventional PID,the controller with ICPSO-PID algorithm has a smaller overshoot,a shorter tuning time and better robustness. The design method proposed in the paper can be applied in a practical electro-hydraulic pitch control system for WTG.