Electric Motors
Description
Electric motors produce mechanical energy by utilizing electric energy. A general motor consists of a fixed stator, movable rotor, armature brushes, axle and field magnet. The electric current is initially fed into the motor by the carbon blocks called brushes, which enter the loop through the slip rings. The magnetic field around the loop, which is caused by the field magnet, causes the loop to turn and provide rotating motion. This rotating motion is transmitted to a shaft to provide the required mechanical energy.
Types
Motors are primarily classified into following types:
Alternating current (AC) motors
AC motor is an electric device that is run by alternating current. It comprises of two fundamental parts — an outside stationary stator that has coils through which AC current is passed to produce a rotating magnetic field. The second part is the inside rotor that is coupled to the output shaft, to which a torque is given.
AC motors are of two types:
Synchronous motors
Induction motors
Direct current (DC) motors
DC motor, also acts on the same principle of AC motors, the only difference that it runs on direct current (DC) instead of alternating current. This is achieved by passing the current through a coil and creating a magnetic field, which spins the motor.
Generally, DC motors are classified into two types:
Brushed DC motors
Brushless DC motors
Features of AC Motors
Simple design
Can be operated at higher speed
Rugged and reliable
Various range of mounting styles
High efficiency
Available in high power ratings
Features of DC Motors
Applications of Electric Motors
Electric motors are utilized in machine tools, power tools, blowers, pumps, household appliances, computer disk drives and industrial fans, and many other applications.