基于在线辨识的锅炉中间点温度GPC-PID控制

GPC-PID Control for Boiler Intermediate Point Temperature Based on Online Identification

针对超超临界直流锅炉中间点温度时变、影响因素多的特点,采用常规的串级PID控制难以达到预期的控制效果,提出了一种基于两阶段闭环在线辨识的GPC-PID控制方法。该方法首先引入基于递归最小二乘(RLS)的两阶段闭环在线辨识算法,辨识出一类变工况下锅炉中间点温度随给水量变化的参数模型,并分别选用了自回归(ARX)模型和有限脉冲响应(FIR)模型作为中间辨识模型,同时将在线辨识模型结合广义预测控制算法(GPC)对PID参数进行实时调节。仿真结果表明,该算法能快速跟踪中间点温度模型参数的变化,有强的抗干扰能力,具有一定的应用价值。

A new method is presented based on two-stage closed-loop online identification GPC-PID, Because the Ultra supercritieal once-though boiler intermediate point temperature has time - varying and factors affecting characteristics, It＇ s difficult to achieve the desired performance by using the general cascade PID control. By using a two-stage closed-loop online identification method based on recursive least squares, a class of variable conditions parameter model is identified. The model is that boiler intermediate point tempera- ture change with feed water flow. Also ARX model and FIR model are selected as transition model. And then generalized predictive con- trol（GPC） algorithm is utilzed to adjust the PID parameters with the online identificated model. The experiment result shows that such method can not only fast track variation of intermediate point temperature model parameters but also have stronge anti - interference ability, and show the effectiveness of the algorithm.