毕业论文--基于plc控制的变频调速在桥式起重机中的应用.doc

基于PLC控制的变频调速在桥式起重机中的应用论文 摘 要 桥式起重机是一种常用的货物运输工具，被广泛的应用于工厂、码头、仓库中。桥式起重机是现代工业生产中重要的载物工具，为国民生产做出了重大的贡献。因此，用户对桥式起重机的安全性、高效性也非常高。传统的桥式起重机采用的是转子串联电阻的方式经行对桥式起重机的控制。这样的控制系统存在着效率底下、可靠性差、操作复杂、耗能巨大、维修困难等缺点。 为了让桥式起重机更符合当前的生产需求，采用新型的控制系统代替原有转子回路串联电阻的调速系统成为从事相关行业专家的研究课题。近年来电力电子技术的不断发展，变频技术也得到了极大的进步。变频器调速技术越来越被广泛的应用于各个领域，特别是应用于一些重型机械中提高了这些机械的整体性能，能够解决系统中存在的诸多缺陷。 本文结合了变频调速技术，提出了基于PLC下控制变频调速系统来实现对桥式起重机的控制。系统采用人机界面实现操作员和PLC的通信，从而达到对桥式起重机的运行控制和故障监测。提高了系统运行的精准度、安全性以及系统的智能程度。 关键词：桥式起重机 变频器 可编程控制器 ABSTRACT Bridge crane is a kind of common goods transport, has been widely used in factories, docks, warehouses. Bridge crane is the modern industrial production important slide in the tool, efficiency is very high. Traditional bridge crane USES is the manner in which the rotor series resistance of the line of control of the bridge crane. Under such control systems there is efficiency, poor reliability, maintenance difficulties shortcomings and so on. In order to make the bridge crane more in line with the current production demand, adopting new type of control system instead of the original rotor loop series resistance speed control system become experts engaged in related industry. In recent years the continuous development of power electronic technology. Frequency converter speed regulation technology is more and more widely applied in various fields, especially applied to some heavy machinery to improve the mechanical performance of the whole, can solve many defects existing in the system. This article combines the frequency control technology, frequency control of motor speed control system based on PLC is put forward to realize the control of the bridge crane. System operators and PLC is realized by using the man-machine interface of communication, so as to achieve control over the operation of the bridge crane and fault monitoring. To improve the precision of the system operation, safety, and intelligent deg