基于PLC空气压缩机变频调速控制系统毕业设计（论文.doc

基于PLC的空气压缩机变频调速控制系统 摘 要 空气压缩机（简称“空压机”）可以将取之不尽用之不竭的空气转换为动力，来推动机械设备转动，减少使用了石油、电力等资源。本设计主要目的是实现可编程控制器和变频器对空气压缩机组的主动控制。本方案通过变频器控制来达到对空气压缩机“一控多”的目的，可编程控制器可以达到变频器的工频与变频自由控制转换的现实需要，以及实现变频器对空压机的转换节制。系统通过压力传感器收集供气管道出口的压力值，经由变频器产生的4-20毫安标准控制信号，该信号又被送到可编程控制器的模拟输入端口，而后通过系统内部PID调节器算法逻辑运算产生控制信号，该信号又被送至变频器。在变频器操控当前机工作模式由变频转化成工频，而供压管道内压力值仍达不到安全工作要求时，则启动下一台空气压缩机，以此类推启动下一台。在变频器输出的电压频率已经变成了20HZ，此时供气管道内的气压量超过预先设定的气压值，系统封闭当前运行的机器，PLC转变操控另下一台。 关键词：PLC，空压机，压力传感器，变频器 Designs based on the PLC air compressor’s supervisory system ABSTRACT The compressor (the air compressor) is a compressed gas to increase gas pressure or gas transportation machine. Air compressor is widely used in nearly all industrial and agricultural, defense, science and technology, civil and other fields. Air compressor safety protection for the production of coal mining enterprises is very important. Programmable Logic Controller (PLC) to the traditional relay control technology, computer control technology and communication technology integration, specifically designed for industrial control of. The design uses PLC and frequency converter to realize the automatic control of air compressor. The program uses inverter of the air compressor dragged more control, PLC to achieve the inverter frequency and frequency conversion control, and inverter switching control of a compressor station. Collection system using pressure sensors Outlet pressure air bag, transmitter output by 4 to 20 mA standard signal to the PLC analog input port, through the internal PID algorithm PLC logic operations, sends control signals to the inverter. When the inverter to control the current machine by the inverter frequency, while the gas pressure is still not satisfied by the PLC control inverter frequency soft-start the next station air compressor to run, and then click Open. So that the production system for good economic and safety performance. KEY WORDS: PLC，air compressor，Pressure transducer，目　录 前　言 1 第1章 空气压缩机 3 1.1 空气压缩机的用途及其优点 3 1.2 空气压缩机