Induction motors are the most commonly used type of motor in table fans. They are simple in design, reliable, and relatively inexpensive to manufacture. Induction motors work on the principle of electromagnetic induction, where an alternating current (AC) flowing through the stator windings creates a rotating magnetic field. This magnetic field induces currents in the rotor windings, which then interact with the stator field to produce torque.
Brushless DC Motor:
Brushless DC (BLDC) motors are increasingly being used in table fans due to their high efficiency, low noise, and long life. BLDC motors use a permanent magnet rotor and an electronically commutated stator to control the rotation of the motor. The stator windings are switched on and off in a specific sequence to create the necessary rotating magnetic field. BLDC motors operate on direct current (DC) power and require an electronic controller to function.
Shaded-Pole Motor:
Shaded-pole motors are a simpler and less efficient type of motor that is sometimes used in low-cost table fans. They work on the principle of shading part of the stator poles with a copper sleeve or ring. This shading creates a phase shift in the magnetic field, which induces currents in the rotor windings and produces torque. Shaded-pole motors are generally less powerful than induction motors and BLDC motors, but they are also less expensive and quieter.
Permanent Split Capacitor Motor:
Permanent split capacitor (PSC) motors are a type of induction motor that uses a capacitor to improve starting torque and efficiency. The capacitor is connected in series with one of the stator windings and helps to create a rotating magnetic field even when the motor is not running at full speed. PSC motors are more efficient than shaded-pole motors and can provide higher starting torque, making them suitable for use in table fans that require more power.