About
AC Motors "The heart
of all AC drive systems is the motor."
The Purpose of the Electric Motor The
purpose of any electric motor is to convert electrical power
into mechanical power.
Induction Motors
The most common electric motor found
in industrial and comercial application is
the AC
induction
motor. Induction
motors work by electrically inducing an
electro-magnetic pole into the rotor. The magnetic field
that surrounds the rotor appears to rotate which has the
effect of
pulling the rotor in the direction of rotation. The speed
of the rotation is determined by the frequency of the applied
alternating
current - change the frequncy and the rotor speed is changed.
This is the function of the variable frequency drive (VFD
or AC drive).
The Stator (Stationary Part)
The rotating magnetic field is produced by
the coil windings when AC power is applied.
The Rotor
Sometimes called a squirrel-cage
rotor because if all of the magnetic iron were removed
what would remain
would be an aluminum cage that looks like a rodent exercise
cage.
