基于内模控制(IMC)的主汽温度控制系统设计

Design of main Steam Temperature Control System Based on Internal Model Control(IMC)

主蒸汽温度和再热蒸汽温度直接影响火电厂的热效率和汽轮机等设备运行的安全性;传统PID控制器的控制规律简单,但是不能根据控制过程中的不确定性变化做出相应调整;当被控对象参数实时变化时,控制器参数不能做出实时调整,这样会导致过程的品质指标变坏;针对超超临界机组过热蒸汽温度和再热蒸汽温度,提出了一种基于内模控制(Internal Model Control,IMC)的PID控制策略,将PID控制、Smith预估控制、确定性及线性二次最优反馈控制和多种预测控制归纳于同一结构之下;以1000MW的电厂机组为对象开展了额定工况下和80%额定负荷下的过热气温和再热气温的PID-IMC控制器设计。

The main steam temperature and reheated steam temperature directly affect the thermal efficiency of the thermal power plant and the safety of the steam turbine and other equipment.The control law of the traditional PID controller is simple,but it can not be adjusted according to the uncertainty in the control process.When the parameters of the controlled object change in real time,the controller parameters can not be adjusted in real time.This will lead to the deterioration of the quality of the process.A PID control strategy based on Internal Model Control(IMC)is proposed for superheated steam temperature and reheat steam temperature.PID control,Smith predictive control,deterministic and linear two times optimal feedback control and multiple predictive control are summed up under the same structure.PID-IMC controller design for overheated air temperature and reheat temperature under rated load and 80%rated load is carried out in 1000MW power plant.