转速开环恒压频比控制的交流异步电动机调速系统仿真Word版

内蒙古科技大学

本科生课程设计论文

题目：转速开环恒压频比控制的交流电

动机速系统仿真

学生姓名：

学号：

专业：自动化

班级：自动化

指导教师：

2012年 11 月 02 日

内蒙古科技大学课程设计任务书

目录

摘要 (4)

Abstract (5)

转速开环恒压频比控制是交流电动机变频调速 (6)

1. 异步电动机仿真意义 (6)

2.说明

(6)

3.变频调速的原理

(6)

3.1基频以下调速

(6)

3.2基频以上调速 (7)

4.仿真过程 (8)

4.1具体步骤

(9)

4.2、所用元器件及其参数设置

(10)

4.3仿真结果 (16)

5.仿真分析

(19)

6.实训总结

. (20)

转速开环恒压频比控制是交流电动机变频调速

摘要：转速开环恒压频比控制是交流电动机变频调速最基本的控制方式，一般变频调速装置都带有这项功能，恒压频比的转速开环工作方式能满足大多数场合交流电动机调速控制的要求，并且使用方便，是通用变频器的基本模式。采用恒压频比控制，在基频以下的调速过程中

可以保持电动机气隙磁通基本恒定，在恒定负载情况下（恒转矩），电动机在变频调速的过程中的转差率基本不变，所以电动机的机械特性较硬，电动机有较好的调速性能。但是如果频率较低，定子阻抗压降所占比重较大，电动机就难于保持气隙磁通不变，电动机的最大转矩将随频率的下降而降低而减小。为了使电动机在低频低速时仍有较大的转矩，在低频时应适当提高定子电压（低频电压补偿），使电动机在低频时仍保持较大转矩。

异步电动机的变压变频调速系统一般简称为变频调速系统。由于在调速时转差功率不随转速而变化，调速范围宽，无论高速还是低速时效率都较高，在采取一定的技术措施后能实现高动态性能，可与直流调速系统媲美。因此现在它的应用面很广，目前交流异步电动机的调速系统已经广泛应用于数控机床、风机、泵类、传送带、给料系统、空调器等设备的电力源和动力源，并起到了节省电能，提高设备自动化，提高产品质量的良好效果.下文在详细分析交流异步电动机变频调速的原理基础上，应用MATLAB/SIMULINK仿真软件，实现了转速开环恒压频比控制的交流异步电动机调速系统的仿真，并且详细分析了仿真结果。

关键词：异步电动机；变频调速；MATLAB 仿真

Abstract：Speed open loop constant pressure frequency ratio control is ac motor frequency control of motor speed is the most basic control mode, general frequency conversion speed control device with the function, constant pressure frequency ratio speed open-loop mode can meet most occasions ac motor speed control requirements, and easy to use, is the basic pattern of general converter. The constant pressure frequency ratio control, in the fundamental frequency of the speed control of the process can keep motor air gap flux basic constant, in constant load cases (constant torque), motor in the process of slip frequency control of

motor speed basically unchanged, so motor mechanical properties is hard, motor has good control performance. But if frequency is low, stator resistance voltage drop proportion bigger, motor was hard to keep the air gap flux invariant, motor torque capacity will decline along with the frequency decreased and reduce. In order to make the motor in the low frequency low speed when there are still large torque, in the low frequency should be an appropriate increase in stator voltage (low-frequency voltage compensation), make the motor in low frequency is still maintain bigger torque.

Induction motor variable voltage variable frequency speed regulation system is usually referred to as the variable frequency speed control system. Because the speed when the slip power does not change with speed, wide range of speed regulation, no matter when high speed or low efficiency is higher, taking a certain technical measures can realize high dynamic performance, but with dc speed control system). So now it's application is very wide, at present ac asynchronous motor speed control system has been widely used in CNC machine tools, fans, pumps, conveyor belts, feeding system, air conditioner, and other equipment power source and power supply, and played a save electric energy, improve equipment automation, improve product quality good results. Below the detailed analysis of ac induction motor variable frequency speed regulation principle basis, the application of MATLAB/SIMULINK software, realize the speed open loop constant pressure frequency ratio control of ac asynchronous motor speed control system simulation, and detailed analysis of the simulation results.

Keywords：Asynchronous motor; Frequency control of motor speed; MATLAB simulation

转速开环恒压频比控制是交流电动机变频调速

1.异步电动机仿真意义