针对蒸汽发生器(steam generator,SG)水位控制过程存在的主要问题,提出1种SG水位自抗扰控制(activedisturbances rejection control,ADRC)系统。基于SG水位变动过程分析,将SG水位控制对象等效为二阶系统,建立SG水位的二阶自抗扰控制系统。该控制系统利用扩张状态观测器对系统的"内扰"和"外扰"实时估计,通过前馈方式给予补偿;同时,通过非线性反馈控制改善控制系统的快速性和稳定性。在水位扰动、给水扰动和蒸汽扰动下,对SG水位自抗扰控制系统进行对比仿真试验,结果表明,建立的SG水位自抗扰控制系统具有良好的控制品质。
The active disturbances rejection control (active disturbances rejection control,ADRC) scheme was presented for resolving the main problems that exist in the steam generator (SG) water level control system.SG water level control was equivalent to a second-order system by analyzing the process of SG water level fluctuation,and a SG water level controller was designed based on active disturbances rejection control theory. In the system extended state observer was used to estimate and compensate the "internal disturbance" and "external disturbance";at the same time,the stability and rapidity of the control system was improved through the nonlinear control system.Besides,the comparative simulation tests of the controller under different disturbances was carried out,the results show that the SG water level control system based on ADRC has a better quality compared to PID control system.