The two most important electric motors are the ac induction motor and the permanent magnet (PM) brushless synchronous motor, also known as the brushless dc or ac servo motor. These motors have ...

Prior to the advent of the adjustable-speed drive (ASD), the polyphase induction motor operated as a constant-speed motor. Figure 1 shows the well-known torque and current curves versus speed for the ...

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 ...

The way we control the speed of fan motors or pump motors has tremendously changed in the past two decades with the introduction of variable-frequency drives (VFDs), aka variable-frequency controllers ...

Ask any system designer to name the top three reasons for specifying a variable-frequency drive (VFD), and you probably won't hear a lot of “maintenance cost reduction” responses in return. Instead, ...

When it’s time to specify a high-performance motor that offers both precise positioning and cost efficiency, stepper motors offer many advantages over DC motors thanks to their brushless technology.

AC induction motors are widely used in industrial applications due to their reliability and low maintenance needs. Comprised of a stator and rotor, these motors convert electrical energy into ...

If you run your variable frequency drives at 60 Hz and below, you are not alone. Nearly all the VFDs in North America operate below this nominal frequency threshold. Yet a growing number of ...

The International Electrotechnical Commission (IEC) defines a servo device as “an adjustable-speed AC power drive system that includes an AC motor integrated by feedback, a converter, and control, ...

It is interesting to look at figures from the Energy Information Administration about where energy gets consumed in our economy. These figures reveal that industrial uses account for 31% of all energy ...