摘要在科学技术高度发展的今天，工业生产各不相同，被控对象日趋复杂，如果采用常规PID控制，控制精度和鲁棒性下降。相较于常规PID控制，模糊控制优势明显，设计模糊控制器时不需用依赖精确的系统数学模型。融合传统PID控制和模糊控制的模糊自整定PID控制，在更大的范围内提高了控制器的性能。模糊自整定定PID控制通过总结现场操作人员的实际运行操作经验，保持传统PID控制器的特点，充分发挥模糊控制的优势，使得工业被控对象获得良好的控制。22511
本次毕业设计的课题是液位控制系统的设计。在设计中，主要负责的是数学模型的建立和控制算法的设计，因此在论文中设计用到的 PID 算法提到得较多，PLC 方面的知识较少。 本文的主要内容包括：液位控制系统的背景和意义、液位控制系统的国内外发展概况、水箱的特性确定与实验曲线分析，以罗克韦尔PLC Logix为控制器设计控制系统，PID 参数的整定及各个参数的控制性能的比较，应用 PID 控制算法所得到的实验曲线分析，整个系统各个部分的介绍和讲解 PLC 的过程控制指令 PID 指令来控制水箱水位。
毕业论文关键词：PID控制 模糊控制 模糊白整定PID 控制 PLC
Abstract
With the high development of science and technology，the automatic control systems get more and m．ore complicated．Ifthe traditional PID control is used，the control accuracy and robustness will be decreased．Compared with the traditional PID control，fuzzy control has many advmatages．The design of fuzzy contrIoiler does not depend on the precise mathematical model of the controlled object；Fuzzy control is easy to be accepted by the operator and be achieved by computer software；RobustnesS and adaptability of fuzzy control are also improved．The performance of the controller will be improved in a wider range by the fuzzy adaptive PID control，which is combined with traditional PID control and fuzzy control．Fuzzy adaptive PID contrell make the system achieve the best control effect by making full use of the successful operating expefience of the Nonlinear adjustment in real time of the opermoL and taking full advantage of the excellent performance of the PID controller．
The graduation design topic is the design of liquid level control system. In the design, is mainly responsible for thedesign of the mathematical model and control algorithm, so the design of PID algorithm used to mention more, PLC in less knowledge. The main contents of this paper include: the background and significance of the liquid level control system, water level control system development at home and abroad, water tank characteristic determination and analysis of experimental curve, by Rockwell PLC Logix as the control system design ofcontroller, control performance compared to the tuning of PID parameters and each parameter, analysis of the experimental curve arithmetic are applied PID control, the various parts of the system are introduced and explained the process control of PLC PID commands to control the water level of the water tank.
Keywords:PID Control;Fuzzy Control;Fuzzy adaptive PID control;PLC
目 录
摘 要 II
ABSTRACT III
1 绪 论 1
1.1 液位控制系统的背景和意义 1
1.1.1 PLC的产生、定义 1
1.1.2 PLC的发展现状 1
1.2 液位控制系统的国内外发展概况 2
1.3 本文的章节安排（内容），论文的重难点 3
1.3.1 本文研究的目的、意义 3
1.3.2 本文研究的主要内容 3
1.4 本论文的结构安排 4
2 液位控制系统概述 5 PLC液位控制系统设计+文献综述:http://www.youerw.com/zidonghua/lunwen_15182.html