Electric motor changes poles for high-speed and torque Richard Ball Engineers at Oxford University have developed an electric motor that can act as a two-pole motor for high-speed operation, or use ...

An important part of determining the correct replacement motor for a particular application is understanding motor speed. In this article, I’ll discuss some of the basic concepts behind ac induction ...

Using variable frequency drives (VFDs) to control the speed of a compressor can provide improved occupant comfort and quieter operation in air conditioning and heat pump applications. Tight ...

A special type of brushless motor is called a limited-angle torquer (LAT). LATs are constrained to produce torque through a rotation angle of less than 180°. But they are widely used to operate ...

A motor-drive servo amplifier's output voltage has a fundamental frequency and amplitude that corresponds to the motor speed, torque, and number of motor poles. PWM amplifiers, by their nature, also ...