单元机组协调系统的多模型自适应解耦控制

针对火电单元机组被控对象多变量、强耦合及模型参数随负荷显著变化的特点,提出一种基于多模型自适应解耦控制的协调控制策略.采用多个固定模型和2个自适应模型并行辨识机组对象的动态特性,在每个采样时刻基于切换性能指标选出最优的局部模型作为当前模型,并据此设计解耦控制器,从而实现全工况运行的自适应控制.同时对多模型控制系统的全局稳定性进行了证明.通过对300MW亚临界直流燃煤机组协调控制系统的仿真表明:该控制策略对负荷变化适应快,且可获得良好的动、静态解耦控制效果.

Coordinated control strategy of power unit based on multiple model adaptive decoupling control

According to the characteristics of the thermal power unit,i.e.,multivariable,strong coupled,and parameters varied with load,a new coordinated control strategy based on multiple model adaptive decoupling control is proposed.Multiple fixed models and two adaptive models are established to identify the dynamic characteristic of the unit.Then,according to the switching index,the best model is selected and the decoupling controller is designed accordingly.The global stability of closed-loop system is proved.Simulation results of the coordinated control system of a 300MW subcritical once-through unit show that the proposed method can rapidly adapt to the load changes and bring about satisfactory dynamic and static decoupling control effects.