The variable frequency variable speed system of three-phase asynchronous motor based on DSP has been researched in this paper.

本文研究一种基于数字信号处理器（DSP）的三相异步电动机变频调速系统。

youdao

This paper introduces a frequency variable control system for elevator driven by linear induction motor, and this elevator has been tested.

设计了一套圆筒形直线感应电动机驱动的电梯全数字变频控制系统，对其进行了试验。

youdao

The paper presents a SPWM frequency variable and velocity variable system with SCR as main switching devices. The proposed scheme has been verified through experiment.

介绍一种以SCR作主开关器件的SPWM控制方式的变频调速系统，并通过实验对提出的方案进行了验证。

youdao

For example, rather than purchase expensive ultra-efficient motors, low cost opportunistic additions to old fans and pumps such as variable frequency drives and demand controls can deliver equal energy savings at a fraction of the cost.

FORBES: Log Baby Log: The Race to The Big New Resource Play You Haven't Heard Of