控制回路性能评价方法及在PTA生产装置的应用

Control loop performance assessment method with applications in PTA production equipment

针对工业现场扰动具有噪声大、易频发、时变的特点,将遗忘因子引入到控制回路性能评价的辨识过程中,提出一种改进的基于最小方差准则的性能评价方法.与传统的方法相比,带遗忘因子的辨识方法不仅能够考虑历史数据的影响,而且能够突出新数据提供的信息量.通过引入遗忘因子参数,能够防止数据饱和,并提高在工业过程时变扰动下控制性能评估的准确性和稳定性.该方法在仿真实验和工业PTA生产应用中得到了论证,结果表明,该方法能够为工业控制回路提供一个准确的性能评价指标,有效指导操作人员对潜在的问题回路进行优化调整,实现生产的平稳运行.

As the noise in industrial processes have remarkable amplitude,frequent happening and time-variant characteristics,an improved performance assessment method based on minimum variance control（MVC）benchmark was presented,in which forgetting factor was introduced to identification process for the performance assessment of control loops.Compared with the traditional approach,the identification method with forgetting factor could not only consider the influence of historical data,but also emphasize the information included in the new data.Through introducing the forgetting factor parameters,data saturation was prevented and the accuracy and stability of control performance assessment was improved in the industrial process with time-variant disturbance.The proposed method was demonstrated by the simulation and industrial PTA process application.The results showed that the method can provide an accurate performance assessment index for industrial control loop,effectually guide the operators to optimize and retune the underlying loops that have potential performance problem,and stabilize the process operation.