饱和环节对2种鲁棒负荷频率控制器控制性能的影响

Influence of saturation elements on two kinds of robust load frequency controller

基于黎卡提方程的设计方法首先确定系统参数变化的边界,然后通过求解黎卡提方程设计鲁棒控制器;基于特征结构配置的设计方法则将闭环系统的特征值配置在特定区域,使闭环系统对参数变化具有最小灵敏度,最终达到提高鲁棒性的目的。线性模型中的仿真研究表明,基于特征结构配置方法设计的控制器具有较好的鲁棒性。但在实际运行中,发电机出力速度约束在电力系统负荷频率控制模型中体现为饱和环节,必须予以考虑。计及该饱和环节后,重新对比2种控制策略却得出不同于前面的结论,仿真显示了其动态过程。

REA（Riccati-Equation Approach） is to determine the bounds of system parameters and to design the robust controller by getting the solution.EAA（Eigenstructure Assignment Approach） is to assign the eigenvalues of close-loop system in the specific location to minimize the system sensitivity to parameter change and improve robustness.The result of simulation with linear models shows that,the controller designed by EAA has better robustness.While in practical operation,the GRC（Generation-Rate Constraint） is a saturation element in the load frequency control model,which should not be ignored.With the consideration of this saturation element,the comparison between two robust control strategies results in different conclusion.The simulative response curves are demonstrated.