2. The rotor resistance per phase of a 4-pole, 50 Hz, 3-phase induction motor are 0.025 and 0.125 ohm respectively. a. Determine the starting current and torque of the motor. b. Find the speed at maximum torque. c. Also find the value of the additional rotor resistance per phase required to develop 80% of maximum torque at starting.

2. The rotor resistance per phase of a 4-pole, 50 Hz, 3-phase induction motor are 0.025 and 0.125 ohm respectively. a. Determine the starting current and torque of the motor. b. Find the speed at maximum torque. c. Also find the value of the additional rotor resistance per phase required to develop 80% of maximum torque at starting.

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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Similar questions

Name three factors that determine the torque produced by an induction motor.
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Q/ A 3-phase squirrel-cage induction motor, at rated voltage and frequency, has a maximum torque of 225 percent and starting torque of 150 percent of full-load torque. Neglect stator resistance and rotational losses and assume costant rotor resistance. Calculate:i) the slip at maximum torque.ii) the slip at full load.
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A three phase, 50Hz, 6-pole squirrel cage induction motor runs at 960-rpm on full load. The stand still rotor resistance and reactance per phase are 0.01 ohm and 0.05 ohm respectively. Express the maximum torque developed in terms of full load toque. Find the slip at which the maximum torque occurs.
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