Single Phase Motors pptx

Single Phase Motors• Similar to a 3 phase induction motor with squirrel cage rotor and main stator windgs.. Main wndgs Laminated stator slots Rotor Wndgs Centrifugal switch... Run ma

Single Phase Motors

• Similar to a 3 phase

induction motor with

squirrel cage rotor

and main stator

windgs.

Main wndgs

Laminated stator slots

Rotor

Wndgs Centrifugal switch

Run (main) and Start (Aux) Windings

• The stator has two sets of

windgs, Run (which is of

thicker size to reduce I²R

losses) and Start of thinner

size is placed 90˚ apart.

• Run has relative Large

number of turns.

• Aux has relative Small

number of turns.

Starting Torque in Single phase motor

• To produce a starting torque a

rotating magnetic field must be produced

• This is done by including the Aux

winding

• When an AC source is applied the

main windg produce a flux while the Aux wndg produces a flux

Since the angles are out of phase a resultant rotating field is created

• A centrifugal switch disconnects the

Aux wndg from the supply after it has run up to 75% of full speed

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Split Phase Principle