Electrical Engineers and Master Electricians (EEAME) Portal

Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

a variable speed controller and motor in which the magnetizing and torque producing components of current are controlled separately. Some vector drives requires rotor position sensors. Vector controlled induction motors can operate over a wider speed range, and may produce rated torque even at zero speed, much like a DC motor. Thus, vector controlled induction motors are often used for applications that might otherwise require a DC motor drive.

wound rotor induction motor

an induction motor in which the secondary circuit consists of a polyphase winding or coils connected through a suitable circuit. When provided with slip rings, the term slip-ring induction motor is used.

written-pole motor

a single-phase motor that uses a coil to write poles on the magnetic rotor. The advantage of the written-pole motor is that it draws much lower starting current, allowing much larger single-phase motors. The development of this motor has been sponsored by the Electric Power Research Institute.

Motor service factor (SF)

The percentage multiplier that a motor can handle for short periods of time when operating within its normal voltage and frequency tolerance. In other words, it is a fudge factor that give extra horsepower when it's occasionally needed.