16-07-2011, 03:28 PM
electric motors - Copy.ppt (Size: 480.5 KB / Downloads: 97)
Introduction
Electromechanical device that converts electrical energy to mechanical energy
Mechanical energy used to e.g.
Rotate pump impeller, fan, blower
Drive compressors
Lift materials
DC Motors – Components
Field pole
North pole and south pole
Receive electricity to formmagnetic field
Armature
Cylinder between the poles
Electromagnet when current goes through it
Linked to drive shaft to drive the load
Commutator
Overturns current direction in armature
AC Motors – Synchronous motor
Constant speed fixed by system frequency
DC for excitation and low starting torque: suited for low load applications
Can improve power factor: suited for high electricity use systems
Synchronous speed (Ns):