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.

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 ...

A fundamental understanding of the speed-torque curve it the key to specifying a dc motor that will do everything it needs to do. Much has been written about the process of selecting motors for ...

Frequently, when it comes to step motor selection, users will select a motor with the highest holding torque rating, assuming that it will give them optimal performance. However, it is an improper ...

Selection of replacement motors is usually straightforward if the ratings are equivalent. Sometimes, however, a different type of motor is necessary or desirable. For success in these cases, it is ...

The same familiar problems. Pick a step motor that’s too big and you’ll end up with vibration. Too small, and it’ll likely stall out. Then there’s rotor inertia. If inertia is too small, you’ll never ...

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 ...

All the motors produce either interaction torque, reluctance torque or a combination of both. The second article in this series discussed the underlying principles common to all motors. As we have ...

Without getting into a long-winded dissertation about torque, we're going to suggest that you dig through your old copies of HOT ROD Magazine and familiarize yourself with the relationship between ...