摘要现在，供风系统的设计的相关问题能够很大程度地影响工业化建设的投资额、投产以及生产期限。本论文为解决常规的由继电器作为控制元件的供风系统中存在的电能损耗严重、调节响应性能较差，不能满足供风可靠性等问题，设计了基于PLC的供风系统，对传统的煤矿动力用风系统进行了改造。该恒压供风系统的逻辑控制由可编程控制器实现，压力的调节由变频器进行。

变频器和可编程控制器PLC作为本恒压供风系统的的核心元件，压力传感器时刻跟踪监控供风管道内的压力，然后将压力信号传递给变频器。由变频器内置的PID将采样值与给定的压力值进行比较并将其偏差值进行处理，将处理后的结果作为三菱变频器的频率的给定输入信号，据此控制三菱变频器的输出频率，从而调节压风机组运转的速度，通过使用PLC来控制风机的变频运行和工频运行的切换。保证供风管道的压力恒定，达到节能减耗的目的。75582

本系统包含四台压风机组，用接触器分别控制压风机组的工频运行和变频运行，用热继电器作为四台压风机电机的的过载保护，用熔断器作为短路保护装置。

该论文有图10幅，表2个，参考文献15篇。

毕业论文关键词：恒压供风  PLC  供风系统  变频调速

Design of Constant Pressure Air Supply System Based on PLC Control

Abstract Nowadays, air supply system design as an important component part in practical design, this system is the key to ensure the safety production in coal。 The air supply system design quality can directly affect the mine construction investment, production and production period。

This paper in order to solve the conventional controlled by relay for the wind system of the power loss and adjusting response performance is not good, can’t meet for reliability problems, such as wind, design the constant pressure air supply system based on PLC, the traditional coal power with wind system is reformed。 The constant pressure air supply system is carried out by programmable controller PLC logic control, the adjustment of the pressure by frequency converter。

Frequency converter and PLC programmable controller as the core of  this constant pressure air supply systems of components, pressure sensor tracking monitoring for the wind he pressure inside the pipeline, and then pass pressure signal to frequency converter。 By the frequency converter built-in PID sampling value compared with the given pressure value and deviation value for processing, it will be treated as the result of the inverter frequency of frequency converter, and then change the fan speed, through the PLC control of frequency and power frequency switching。 Guarantee for the wind pipe pressure constant, achieve the goal of energy conservation and consumption reduction。

This system contains four winf pressure units, respectively with contactor to control the compressed air unit to run power frequency and frequency conversion, using thermal relay as four compressor motor overload protection, with the fuse as short circuit protection device。

Key Words: constant pressure control   PLC  for the wind system  frequency control

目  录

摘要Ⅰ

Abstract-Ⅱ

目录Ⅲ

图清单-Ⅳ

表清单-Ⅳ

变量注释表-Ⅴ

1 绪论1

1。1恒压供风系统的背景和意义1

1。2恒压供风系统的国内外研究现状2

2 恒压供风系统的工作原理-5

2。1供风系统的基本特征5

2。2压风机简介5

2。3变频调速原理-6

2。4调速运行的节能原理7

3 恒压供风系统的硬件设计-9

3。1恒压供风系统的方案设计9