Adjustable speed drives (ASDs) or variable speed drives (VSDs), also called variable frequency drives (VFDs), typically control a motor's velocity or torque output. Most adjustable frequency drives ...

You can divide the world of electronic motor drives, which control the speed, torque, direction, and resulting horsepower of a motor, into two categories: ac and dc. An ac drive controls ac induction ...

What is a variable frequency drive? Heating, ventilation, and air conditioning systems' air supply used to be constant volume into a space. Now a variable air volume control is being used to provide ...

Variable frequency drives (or VFDs) are widely used throughout industry to provide adjustable speed control of ac motors. Although modern versions are relatively simple to install and operate, VFDs ...

When Tesla first introduced the 3-phase alternating current (AC) induction motor in 1888, he knew that his invention was more efficient and reliable than Edison's direct current (DC) motor. However, ...

Although much has been published on variable-frequency drives (VFDs), people continue to be confused by them. The intent of this article is to provide a basic overview of these devices by evaluating ...