三相异步电动机的闭环恒速控制系统.doc

毕业设计论文
三相异步电动机的闭环恒速控制系统
孙瑶
指导老师姓名: 徐瑾瑜
专业名称: 电气自动化技术
班级学号:
论文提交日期: 2010年12月09日
论文答辩日期: 2010年11月17日
【摘要】系统的输出量返回到输入端并对控制过程产生影响的控制系统称为闭环控制系统。本文介绍了闭环控制系统的组成、PLC系统控制程序、系统的调试等。
基于反馈原理建立的自动控制系统。所谓反馈原理,就是根据系统输出变化的信息来进行控制,即通过比较系统行为(输出)与期望行为之间的偏差,并消除偏差以获得预期的系统性能。在反馈控制系统中,既存在由输入到输出的信号前向通路,也包含从输出端到输入端的信号反馈通路,两者组成一个闭合的回路。因此,反馈控制系统又称为闭环控制系统。反馈控制是自动控制的主要形式。自动控制系统多数是反馈控制系统。在工程上常把在运行中使输出量和期望值保持一致的反馈控制系统称为自动调节系统,而把用来精确地跟随或复现某种过程的反馈控制系统称为伺服系统或随动系统。

【关键词】闭环控制系统、反馈、PLC
[abstract] the system output returns to the input and the influence of the control process control system called closed-loop control system. This paper introduces the closed-loop control position, PLC system control procedures, the system missioning etc.
Based on feedback principle established automatic control system. So-called feedback principle, is according to the system output variation of information to control, namely through systemic behavior (output) and expected behavior, and eliminate the deviation between the deviation to achieve the expected system performance. In the feedback control system, the existing by input to the output signal prior to access, also contains from the output terminal applied input signal feedback path, both form a closed loop. Therefore, feedback control system also called closed-loop control system. Feedback control is automatically controlled main forms. Automatic control system are mostly feedback control system. In engineering often put in operation of make output and expectations to maintain consistent feedback control system known as automatic adjusting system, and had used to accurately follow or reiteration some process feedback control system known as servo system or servo system.
[key words] closed-loop control system, feedback, PLC
目录
绪论 1
第一章光电编码器 2
2
: 2
第二章可编程序控制器(PLC) 3
S7-200PLC简介 3
PLC的基本组成及工作原理 3
PLC的特点 4
第三章变频器 5
5
变频器调速原理 5
6
第四章触摸屏 7
7
7
第五章控制方案及梯形图 8