Q28/For a 3-phase slip-ring induction motor, the maximum torque is 2.5times the full-load torque andthe starting torque is 1.5 times the full-load torque. Determine the percentage reduction in the rotorcircuit resistance to get full-load slip at 3%.Neglect stator impedance.Ans[ 56.8%]Q29/A 3-phase induction motor has a synchronous speed of 250 r.p.m. and 4% slip at full-load. The

Given data, A 3-phase slip ring IM τmax=2.5τflτst=1.5τflsfl=0.03

Q28/ For a 3-phase slip-ring induction motor, the maximum torque is 2.5times the full-load torque an the starting torque is 1.5 times the full-load torque. Determine the percentage reduction in the roto circuit resistance to get full-load slip at 3%.Neglect stator impedance. Ans[ 56.8%]

Q28/ For a 3-phase slip-ring induction motor, the maximum torque is 2.5times the full-load torque an the starting torque is 1.5 times the full-load torque. Determine the percentage reduction in the roto circuit resistance to get full-load slip at 3%.Neglect stator impedance. Ans[ 56.8%]

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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Concept explainers

Three Phase Induction Motor

The induction motor is an electric motor that runs on AC (alternating current) and it is of two type single phase motor that work on single-phase power supply and three-phase motor that work on three-phase power supply.

Question

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Q28/
For a 3-phase slip-ring induction motor, the maximum torque is 2.5times the full-load torque and
the starting torque is 1.5 times the full-load torque. Determine the percentage reduction in the rotor
circuit resistance to get full-load slip at 3%.Neglect stator impedance.
Ans[ 56.8%]
Q29/
A 3-phase induction motor has a synchronous speed of 250 r.p.m. and 4% slip at full-load. The

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