《串级控制在合成一段炉上的应用》-毕业论文（设计）.doc

徐强： 串级控制在合成一段炉上的应用 四川理工学院本科毕业（设计）论文 徐强： 串级控制在合成一段炉上的应用 PAGE \* MERGEFORMAT II 摘 要 合成一段炉是大型合成氨厂的关键设备之一，一段炉出口温度是转化工艺段的重要控制参数，出口温度控制的稳定性和快速性方面均有较高要求。因合成一段炉的大热容量，传热过程的滞后和温度变化的相对延迟，传统的单回路控制系统难以满足控制要求。本文研究了串级控制控制系统的基本组成结构，并通过与单回路控制系统的比较，分析了串级控制系统在提高系统工作频率，增强抗干扰能力和自适应能力方面的优势，探讨了串级控制系统的设计、参数整定方法。在对合成一段炉对象建模基础上，求解出燃烧天然气流量到合成一段炉出口温度的传递函数，设计出相应的串级控制系统，并利用simulink仿真器对该系统进行了相应的仿真实验。 关键词：合成一段炉；串级控制；建模；传递函数；Simulink；阶跃响应 ABSTRACT Application of Cascade Control in Primary Reformer of Ammonia Synthesis Plant Primary reformer of ammonia synthesis plant is one of the key equipment in a large ammonia plant .The temperature of primary reformer outlet-gas is an important control parameters in transformation process section. The temperature of the outlet-gas control has higher requirements in swiftness and accuracy. Due to the large heat capacity of primary reformer of ammonia synthesis plant, heat transfer and temperature changes lag relative delay; the traditional single loop control system can not meet the requirements of the control. In this paper, control system elements of the cascade control structure have been studied , an analysis of advantages of cascade control system in improving system operating frequency, enhancing anti-jamming capability and self-adaptive ability by comparing with single-loop control system .The design method and parameter tuning methods of the cascade control system have been discussed .Base on the object modeling of primary reformer of ammonia synthesis plant, the transfer function of the flow rate of burning natural gas to the temperature of outlet-gas were solved ,and the corresponding cascade control system was designed, then simulink simulator was used to do corresponding simulation experiment . Key words： Primary reformer of ammonia synthesis plant；Cascade control； Modeling；Transfer function；Simulink；Step response 徐强： 串级控制在合成一段炉上的应用 PAGE 目录 TOC \o 1-3 \h \u HYPERLINK \l _Toc28292 摘 要 PAGEREF _Toc28292 I HYPERLINK \l _Toc20