文档介绍：Xxxxx等专科学校
毕业设计论文
论文题目:桥式起重机的变频调速系统设计
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2012年12月 12日
摘要
电气调速控制的方法很多,对直流驱动来讲60年代采用发电机—电机系统。从控制电阻分级控制,到交磁放大控制,到可控硅SCR激磁控制,到主回路可控硅即晶闸管整流供电系统。随着电子技术的飞速发展,集成模块出现,计算机、微处理器应用,因此控制从分立组成模拟量控制发展至今天的数字量控制。
从交流驱动来讲:常规的常采用绕线式电动机转子串电阻调速,为满足重物下放时的低速,一般依靠能耗制动、反接制动,后来还采用涡流制动,还有靠转子反馈控制制动、反接制动、单相制动器抱闸松劲的所谓软制动,随着电子技术的发展,国内外开发研制变频调速,PLC 可编程序控制器的应用控制系统的性能更加完美。
本次设计采用PLC和变频器技术,以PLC控制变频器,即以程序控制取代继电—接触器控制,控制变频器实现变频调速,设计出PLC控制的桥式起重机的变频调速系统,进而实现了起重机的半自动化控制。
关键词:PLC 桥式起重机矢量控制
ABSTRACT
Electric speed control method are many, the dc drive speaking in the s the generator - machine system. From the control resistance hierarchical control, to pay ic amplifier control, to the silicon controlled SCR excitation control, to the main loop thyristor is thyristor rectifier power supply system. With the rapid development of electronic technology, integrated module appear, computer, microprocessor application, therefore control from ponent analog control development to today's digital volume control.
From the ac drive speaking: conventional is often used to wound rotor motor rotor resistance control, in order to meet the weight transfer to a lower level of low speed, generally rely on energy consumption braking, reverse connect braking, and then the eddy current brake, and rely on rotor feedback control braking, reverse connect braking, single-phase brake contracting brake slacken so-called soft brake, with the development of electronic technology, the domestic and foreign development frequency control, PLC programmable controller to control the application of the performance of the system more perfect
This design USES PLC and frequency converter technology, PLC control frequency converter, namely to program control instead of relay, contactor control, control frequency converter to realize frequency control of motor speed, design the PLC control of bridge crane of variable speed control system, then realize the crane half automation control.
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