超超临界机组机炉协调系统的模糊抗扰动预测控制

摘要

为了同时克服超超临界机组机炉协调系统的大范围负荷跟踪和扰动抑制问题,提出了一种利用模糊调度、模型预测控制及扩张状态观测器等技术的模糊抗扰动预测控制方法.首先,在非线性度分析和子空间辨识的基础上,建立受控对象的局部状态空间模型.为了增强控制器的扰动抑制性能,采用扩张状态观测器估计未知扰动和模型失配.然后,利用估计出来的扰动,设计基于局部模型的局部预测控制器并通过模糊调度技术将它们结合成模糊预测控制系统以进一步提高性能.仿真结果表明,所提模糊抗扰动预测控制器能够在负荷大范围变化时取得较好的跟踪性能,同时对于扰动产生的不良影响具有抑制能力.%In order to overcome the wide-range load tracking and unknown disturbance issues of an ultra-supercritical boilerturbine unit,a fuzzy disturbance rejection predictive control approach is proposed using the techniques of fuzzy scheduling,model predictive control and extended state observer.Local state-space models are established on the basis of nonlinearity analysis and subspace identification.To enhance the disturbance rejection capability of the controller,an extended state observer is employed to estimate unknown disturbances and model mismatches.The disturbance estimation enhanced local predictive controllers are subsequently devised based on the local models,the performance of which is further strengthened by incorporating the fuzzy scheduling technique.The simulation results verify the merits of the proposed strategy in achieving satisfactory wide-range load tracking and disturbance rejection performance.