基于恒压频比的交流异步电机调速研究

AC asynchronous motor speed governing research based on constant V/F mode

为了满足部分应用场合对电机调速系统有一定的调速范围而速度响应不必太快的要求,设计了一个基于恒压频比的变压变频调速系统.通过在调速过程中令交流电压及其频率同时改变,并使电机的气隙感应电动势幅值和电压频率之比为一个常数,对三相交流电动机进行调速.在Matlab/Simulink环境下分析交流异步电机控制原理及其数学模型,对其进行恒压频比调速的仿真研究.结果表明,电机的机械特性近似于他励直流电机的降压调速特性,也验证了该种控制方法的简洁性和实用性.

In order to meet the requirements that there is a certain speed range but it is without too fast speed of response in many applications, a VVVF speed governing system based on constant U/f was set up. By making the AC voltage and its frequency change at the same time and make the ratio of the induced electromotive force amplitude of the air grap of motor voltage amplitude and frequency be a constant in the process of speed regulation, the three-phase alternating-current motor was regulated in speed. With the analysis of AC asynchronous motor control principle and its mathematical model in the Matlab/Simulink environment, the simulation was conducted to research VVVF speed governing.The results show that mechanical characteristics of motor are similar to the buck speed governing charac-teristics of separately excited DC machine,and this verify the simplicity and practicability of this kind of control method.