摘要
开口闪点仪对温度控制精度要求较高,采用常规PID控制难以达到国标中规定的线性度。运用最小二乘法的一阶惯性加滞后模型直接辨识法,辨识出温度控制系统的传递函数模型;然后,结合内模控制原理,设计了仅需调整一个参数的IMC-PID控制器。在模型匹配和失配两种情况下,与Ziegler-Nichols法和Cohen-Coon法整定的PID控制器仿真对比,通过调整滤波器时间常数仍能获得较好的线性度。并将该算法应用到开口闪点仪温控系统中,仿真和实际应用均表明,IMC-PID具有较强的鲁棒性和较好的动态特性。
It is difficult to get perfect performance to use the conventional PID controller, because the system needs high precision temperature control. Transfer function of temperature control system was identified by using the direct identification method which is based on the least square method for the first-order plus delay time model. Then, combined with internal model control principle, an IMC-PID controller was designed, which is simple and only needed to adjust one parameter. Compared with Ziegler-Nichols and Cohen-Coon tuning method of PID controller, simulation had been done in model match and mismatch cases. By adjusting the time constant of filter, better linearity can be got even in the case of model mismatch. Last, put it into practice in the system to improve the precision. Both simulation and application shows that, IMC-PID is of strong robustness and good dynamic characteristics.
出处
《自动化与仪表》
北大核心
2009年第11期36-39,共4页
Automation & Instrumentation
关键词
闪点仪
直接辨识
内模PID
线性升温控制
flash-point instrument
direct identification
internal model control PID（IMC-PID）
temperature control
