Induction motors unit iii

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INDUCTION MOTORSName : Mrs.A.Sangari & Mrs.P.T.SubasiniDesignation : Sr. Lecturer & LecturerDepartment : Electrical and Electronics Engineering

Subject code : 131307Year : II/ECE A & BUnit : IV

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induces a large voltage – hence large currents flow within the

rotor,

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producing a strong torque.

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Induction Motors: Slip

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The difference between the synchronous speed and rotor

speed can be

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expressed as a percentage of synchronous speed, known as

the slip.

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N Ns - s =

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Ns

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s = slip, Ns = synchronous speed (rpm), N = rotor speed

(rpm)

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• At no-load, the slip is nearly zero (<0.1%).