摘要： 首先，论文介绍了粉笔自动包装机电气控制系统的组成，S7-200系列PLC的特点，常用的PLC控制系统的程序设计方法。并说明系统采用PLC控制及变频调速的重要意义。其次，论文在对粉笔自动包装机的工作过程及控制要求进行深入探讨的基础上， 选择了PLC的型号和硬件配置，分配了I/O地址，设计了PLC外部硬件接线图。为了提高系统的可靠性，较深入的研究了系统的抗干扰问题。在系统软件设计方面，对开关量控制部分采用顺序控制设计方法，设计了系统程序流程图和顺序功能图。对模拟量闭环控制采用PID控制算法，手动程序则釆用经验法设计了梯形图。为了降低成本，对需要调速的输送带电动机及链条驱动电动机，提出了用变频调速取代直流调速的方案。设计了变频调速系统的电路图，说明了应用变频器时须注意的问题6676
关键词：粉笔自动包装机，可编程序控制器，顺序控制，PID控制
The research and design of the electric control system of chalk
Abstract：At the beginning of the paper, the electric control system constitution of chalk TRAY Loader and the characteristics of SIMATICS7-200 are introduced, generic system design methods with PLC are presented, the significance of the application of PLC and frequency converter is emphasized.Second，make a thorough cognition about the working process and control request of the chalk TRAY Loader，selective style of PLC and hardware organization, I/O address distribution and the design for electric connection map of the hardware organization. To improve the reliability of the system, the interference produced from the inductance loaders has also been disposed. The order controlling design method is used in the part of the switch amount controlling, and the flow chart of systematic procedure and function flow chart of the order are designed. The PID Control algorithm is used in the Analog quantity closed loop control，and the PID order method is introduced. Frequency conversion speed adjusting and the application of and frequency converter are in the chapter four: According to the systematic control request, the electrical machineries of conveyer belt and the roller chain driver are needed to speed regulate, and the importance about the direct current speed regulating being replaced with frequency conversion speed regulating is pointed out The circuit diagram about frequency conversion speed regulating is designed, and the questions that needing paying attention to while using the frequency converter is introduced.
KeyWords：The electric control system of chalk，Programmablecontroller,Order control,PID control
目录
1. 绪论5
1.1 国内外现状及本文系统概述5
1.2可编程序控制器的发展及应用状况5
1.3变频器简介7
1.4系统设计方法8
1.5本文的工作8
2．系统硬件设计10
2.1 粉笔包装机的工作过程及控制要求10
2.1.1 系统中各元件功能及工作过程10
2.1.2控制要求12
2.2 PLC的型号和硬件配置13
2.3系统各元器件的I/O地址分配16
2.4 PLC外部硬件电路设计 19
2.4.1    CPU224的外部接线19
2.4.2用分时分组输入减少所需输入点20
2.4.3输入输出的硬件保护电路设计21
2.4.4用数码显示实现满盘计数22
2.5本章小结 25         
3．系统软件设计26
3.1控制系统程序结构26
3.2自动工作程序设计26
3.2.1工艺流程图设计27
3.2.2顾序功能图设计27   
3.3 PID闭环控制系统33
3.3.1模拟量输入的处理34
3.3.2定时中断34
3.3.3 PID程序设计35
3.4 满盘计数显示子程序设计36
3.5手动程序设计38
4. 结论39
4.1 本文解决的主要问题39
4.2 需要进一步研究的问题40 PLC粉笔自动包装机自动控制的设计+电路图:http://www.751com.cn/zidonghua/lunwen_4307.html