基于前馈模糊反馈的苛化温度控制系统设计

Design of Temperature Control System in Causticizing Process Based on Fuzzy Feed-forward Feed-back Control

中文关键词:  苛化过程  温度控制  前馈  模糊反馈  Smith预估器

Key Words:caustic process  temperature control  feed-forward  fuzzy feed-back  smith predictor

中文摘要:

      针对苛化过程的大时滞、大惯性、参数时变等特点,对单回路苛化温度PID控制系统进行改进,设计了一种基于模糊逻辑的前馈反馈温度控制系统。同时分析了前馈反馈系统的局限性,探讨了Smith预估器在其中的应用。结合传统模糊PID反馈控制器,利用前馈控制补偿可测干扰——蒸汽压力对苛化温度的影响。仿真结果表明,与传统单回路控制相比，改进的控制系统具有更好的动态特性和鲁棒性。最后给出了该控制系统的应用实例,验证其具有良好的控制效果。

Abstract:

      Causticizing process is a large inertial, large time-delay, time-varying process with many random disturbances. Aiming at these problems, this paper improved the single-loop PID temperature control system and presentsed the feed-forward feed-back temperature control system based on fuzzy logic. This paper analyed the limit of applying the feed-forward feed-back system and discussed the application of Smith predictor. Combined with traditional fuzzy PID feed-back controller, the fuzzy feed-forward control system was applied to compensated the impact of vapor pressure on causticizing temperature. Simulation result showed that improved control system was much better than the traditional single-loop PID control system in dynamic performance and robustness. At last the paper also verified its excellent control effect by practical applications．