基于西门子PLC的中央空调变频调速系统设计

电气自动化论文编号:ZD087         字数:16643,页数:44  

目 录
第1章 绪论   1
1.1 总体设计方案的确定   1
1.2 中央空调的结构原理   1
1.3 基于PLC控制下的变频调速系统工作原理   4
1.4 中央空调变频调速的意义   7
第2章 I/O口外围电路设计   8
2.1 系统的设计原则   8
2.2 模拟量输入模块选取   9
2.3 模拟量输出模块的选取   12
2.4 温度检测部分设计   14
2.5 显示电路设计   14
2.6 变频器的选择及主电路设计   16
第3章 PLC的选择及接口电路设计   21
3.1 PLC的特点   21
3.2 PLC的选择和应用   22
3.3 输入输出点地址分配   23
第4章 PLC控制中央空调变频调速系统的软件设计   25
4.1 内存变量分配   25
4.2 主程序设计   26
4.3 温度手控   28
4.4 冷却水系统PID调节   30
4.5 冷冻水系统PID调节   32
4.6 传送PID参数   33
4.7 中断服务   34
结论   39
参考文献   40
致谢   41
附录   42

摘 要
随着社会进步和经济的高速发展，中央空调的应用也越来越广泛，为创建高效、节能、舒适、安全的工作和生活环境奠定了基础。传统的中央空调存在着很多的缺点，因此在这种形势下中央空调空调应运而生。
本文所述中央空调变频调速系统主要由西门子PLC、温度传感器、变频器、电机以及其它低压保护和控制电器元件构成。整个系统采用模块化设计，CPU主模块采用CPU226，模拟量扩展模块采用EM231，可根据需要灵活配置各模块的数量。根据PLC输入输出量的多少,来决定PLC所需的点数,进而选取相应的大小的PLC. 温度检测部分设计；选择变频器；设计主电路；对制冷设备信息进行采集、显示、其中制冷管道温度传感器对制冷管道温度进行数据采集和对系统设备集中控制，更直观的显示现场系统在运行中的各种工况数据,提高了系统的可靠性。
对系统进行自动控制，该控制系统采用了先进的测控、变频、工业自动化、和通讯网络技术，设备的各项报警和保护功能齐全，安全系数大大提高。通过软件设计完成中央空调所需的参数设置和控制要求，系统软件由主程序、初始化程序、模拟量检测程序组成，通过调用子程序来完成系统的数据采集、模拟量检测和声光报警等功能。

关键词:中央空调；可编程控制器；变频调速

Abstract
Along with society progress and economy of high speed development, central air condition of application also more and more extensive, for establish efficiently, economy energy, comfort, safety of work and the living environment lay foundation.The central air condition existence of tradition much weakness, so the central air condition air condition emerge with the tide of the times under this kind of situation.
This text say a central air condition to change Pin to adjust soon system main is spread a feeling machine by the Siemens PLC, temperature and change Pin machine, electrical engineering and other low pressure protection and control electric appliances component constitute.The whole system adoption mold piece turn design, CPU lord mold piece adoption CPU226, imitate the quantity expand a mold piece adoption EM231,According to PLC importation output quantity of how much, decision the point need by PLC, then selection correspond of the PLC of size. Temperature examination part design;The choice change Pin machine;Design lord electric circuit;Carry on collect towards making a cold equipments information, manifestation, make cold piping temperature to spread a feeling machine among them to make cold piping temperature to carry on a data to collect and to system equipments concentration control, more keep the manifestation of view the spot the system is in the movement of various work condition data, exaltation the credibility of the system.
To the system carry on auto control, should control system adoption forerunner of measure and control, changing Pin, industry automation, with communication network technique, equipments of each with protection the function be well-found, safety coefficient consumedly exaltation.Pass software design completion the parameter need by central air condition constitution and control request, system software from lord procedure, start to turn procedure, imitate quantity examination the procedure constitute, the data which pass to adjust to use sub- procedure completion system collect, imitate quantity examination harmony light report to the police etc. function.

Key words：Central air condition;Programmable controller;Change the Pin adjust soon