基于模糊串级控制的黑液浓度控制系统设计

摘要

Abstract:The concentration of black liquor is typically non-linearity,time-variable,big delay,big inertia in the alkali recovery of paper industry.Considering these problems,this paper explored the application of fuzzy control system in black liquor concentration control.A cascade control method based on fuzzy self-tuning PID controller was proposed.Because fuzzy control does not rely on the mathematical model of the object to be controlled,the control system conbimes the advantages of the cascade control and the fuzzy control and adjusts the PID parameters real-timely.Compared with the conventional black liquor cascade control,the simulation result indicated that this control strategy has the stronger self-adaptiveness and the good control quality,and can control the concentration of black lquor effectively.Its excellent control effect was verified in the pratical application.%造纸碱回收过程中黑液浓度是典型的非线性、时变、大时滞、大惯性对象,针对这些问题探讨了模糊控制系统在黑液浓度控制中的应用,提出了基于模糊自校正PID的串级控制方案.利用模糊控制不依赖被控对象的数学模型,该控制系统将串级控制和模糊控制优势相结合,实时调整PID控制器参数.仿真结果表明,该控制策略比常规黑液浓度串级控制具有更强的自适应能力和良好的控制品质；实际应用案例表明,黑液浓度模糊串级控制可有效控制黑液浓度.