【作者】 徐顺帆；

【导师】 仲崇权；

【作者基本信息】 大连理工大学 ， 检测技术与自动化装置， 2010， 硕士

【摘要】 加热反应是化学实验中十分常见的化学反应之一。电加热炉结构简单、密封性能好,适用于各类化学反应场合,因此得到了广泛地应用。由于在加热过程中电加热炉的特性参数实时改变,应用一般的PID控制方法无法解决超调和滞后问题。本课题有关加氢脱硫催化反应温度控制的研究正是基于这种应用背景提出来的。分析了所研究的电加热炉产生超调和滞后的原因,介绍了模糊控制系统的结构,对模糊控制原理中模糊子集、隶属函数、模糊语言以及推理规则进行了分析,并对几种常用的模糊逻辑系统的优缺点进行了比较。针对催化反应对温度控制的要求和电加热炉的系统特性,研究了一种带多个调整因子的模糊控制方法。这种控制方法针对被控对象的不同状态,通过修改后的调整因子的值来改变各个输入量在计算模糊输出时所占的权重,实现了模糊控制的智能化,解决电加热炉在加热过程中出现的超调问题,改善了电加热炉在升温过程中的升温速度剧烈波动的问题。介绍PLC(可编程逻辑控制器)的性能指标和编程语言,将PLC作为系统的主控制器,通过编程进行模糊控制,并采用指针实现PLC的多段程序升温控制。采用Visual Studio.NET在计算机上开发监控软件,使用MODBUS TCP协议与PLC进行以太网通讯。监控软件分为数据处理模块和参数设置模块,数据处理模块实现对采集数据的储存和显示,参数设置模块对温度控制参数以及监控系统参数进行设置。通过实验验证,采用带多个调整因子的模糊控制算法能有效地解决电加热炉温度控制中的温度超调和升温速度问题,达到预期的控温效果。更多还原

【Abstract】 In chemical experiments, Heating reactions are quite common chemical reactions In chemical experiments. As Electric heating furnace is applicable to all kinds of chemical reaction occasions because of its simple structure and good sealing performance, it had been widely applied. However, furnace characteristic parameters are real-time changed in the process of heating, it is highly difficult to solve overshoot and lag issues with the application of general PID control method. The topic about temperature control in the hydrodesulfurization catalytic reaction is based on this application background.Reason of overshoot and lag electric heating furnace generated is exactly analyzed, and structure of fuzzy control system is introduced. Moreover, advantages and disadvantages of several common fuzzy control logical systems are well compared by analyzing the fuzzy subsets, membership functions, fuzzy language and reasoning rules in fuzzy control principles.For temperature control-requirements in catalytic reactions and system characteristics of electric heating furnace, it presented a fuzzy control method with multiple adjusting factors, which can alter input weight in the-process of fuzzy output calculation according with changed adjusting factor. Therefore, implemented intelligence of fuzzy control, figured out overshoot issues in heating process, and reduced dramatic fluctuation of heating rate in temperature rise process of electric heating furnace.Introduced and programmable of PLC (programmable logical controller), used PLC as main controller of system to realize fuzzy control, and used Pointers of PLC to implement multisegment programming temperature rising control.Developed monitor software on the computer using Visual studio.net, and achieved PLC Ethernet communication adopting MODBUS TCP protocol. This software is divided into data processing module which implements for store and display of collected data and parameters Setting module for the parameters about temperature control and system monitor related.It has been verified effectively that algorithm of fuzzy control with adjusting factors could not only solve overshoot and heating rate issues in the process of temperature control of electric heating furnace, but also attain the prospective temperature control effects.更多还原