精馏过程的模糊无模型自适应协调控制方法

Approach to Fuzzy Model-Free Adaptive Coordinating Control for Distillation Processes

研究多变量协调控制问题,针对模型未知且具有强耦合特性的多输入多输出乙醇-水精馏过程,主副被控参数的控制要求不同,常规PID控制性能差,当出现显著的不可测干扰时,应协调相关的操纵变量,既保证关键参数不偏离期望值,又使得其它被控过程参数的波动较小。为了解决上述问题,提出了一类模糊无模型自适应协调控制方法。无模型自适应控制结构,通过充分利用过程控制参数的偏差和偏差变化率等信息,建立了主副控制参数不同控制目标的模糊规则,自适应地改变无模型自适应控制器的参数。该方法能够有效地协调乙醇-水精馏过程,达到主副被控参数的控制要求,扩展了无模型自适应控制方法的应用范围。过程实例研究验证了所提出技术方法的有效性。

Dealing with multivariable coordinating control problems and regarding multi-input multi-output （MI- MO） ethanol-water distillation processes with unknown process models and strong coupling characteristic, the control requirements of main and deputy controlled parameters are different and PID control method has poor performance. In the presence of immeasurable disturbances, it is imperative to coordinate the related manipulate variables to ensure both main parameters keeping at desired values and the other process parameters running smoothly. In this context, a control approach of fuzzy model-free adaptive coordinating was introduced. Taking the advantage of model-free adap- tive control （MFAC） metrics, deviations and deviation changes of measurements were utilized to accommodate fuzzy rules concerning alternative control performances of main and deputy controlled parameters which can be employed to adaptively update the parameters of corresponding model-free adaptive controllers accordingly. This novel strategy is eligible for solving coordinating control problems of ethanol-water distillation processes, meeting the control require- ments of both main and deputy controlled parameters as well as extending the application scope of model-free adaptive control. The case study demonstrates the effectiveness of the contribution.