1、 I 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
2、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 四川理工学院本科毕业(设计)论文 II 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
3、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
4、 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 mode