交流异步电机变频调速时电流和转速监测系统设计.doc

PAGE 27  PAGE 49 交流异步电动机变频调速时电流和转速监测系统设计 摘要 最近几年，随着新型电力电子器件的不断涌现和计算机技术的飞速发展，高性能的交流电动机参数监控系统得到了广泛的应用，它的显著的节能效果和灵活的运行方式，给人们留下了深刻的印象。 本毕业设计论文给出了交流异步电动机变频调速实验系统PLC程序设计的基本内容，主要包括对交流电机的监控系统进行了硬件和软件的设计。在硬件上主要详细介绍了三菱PLC、特殊功能模块、三菱FR-A700变频器、编码器及互感器的工作原理、性能特点、使用方法、接线说明，给出了监控系统原理框图和实际的接线图；软件的设计主要实现对交流异步电机运行过程的数据监测，通过FX2N-4AD模块测量电机中的工作电流，通过变频器的特殊端口测量其工作电压，通过FX2N-4AD测量磁粉制动器的工作电流，通过PLC的内部高速计数器测量电动机的转速；最后通过与监控软件进行联机调试和测量，观察记录各种数据，根据实验数据可以分析电动机和变频器的工作特性，并设计了实验用表和分析计算方法。 经相关的实验及组态监控软件的仿真，表明该系统满足预期的设计要求。 关键词： 交流电机，变频器，PLC，参数监控，编码器，互感器 THE PROGRAM DESIGN OF PLC TO FREQUENCY CONTROL OF SPEED EXPERIMENT SYSTEM OF AC ASYNCHRONOUS MOTOR ABSTRACT In recent years, with the new emerging power electronic devices and the rapid development of computer technology, high-performance AC motor parameter monitoring system has been widely used, and its remarkable energy-saving effect and flexible operation mode, giving people a deep impression on it. This article described the basics of AC induction motor VVVF System PLC Programming, It outlined the development and application in China and the future in this field should be done in; secondly，to conduct a systematic analysis of the system schematic diagram, control circuit, electrical control circuit, as well as hardware and software , then the implementation of the program of the monitoring system were demonstrated. In this article，hardware design was be done in Ac motor control system, it described the working principle and characteristics of Mitsubishi PLC, characteristics and function modules, Mitsubishi FR-A700 converter, encoder, and transformer in detail. The design of software is to monitor the data in the process of AC motor running，we can use Mitsubishi PLC and transducer, as well as configuration monitoring software to control the AC motors, we can measure the voltage in circuit by FX2N-4AD module, and measure the speed of AC motor by internal counter of PLC. Then observe the data for debugging, the we can obtain the results of