six poles three-phase squirrel-cage induction motor, connected to a 50 Hz three-phase feeder, possesses a rated speed of 975 revolution per minute, a rated power of 90 kW, and a rated efficiency of 91%. The motor mechanical loss at the rated speed is 0.5% of the rated power, and the motor can operate in star at 230 V and in delta at 380V. If the rated power factor is 0.89 and the stator winding per phase is 0.036 Ω d. Determine the current absorbed at the stator if the windings are connected in delta e. Determine the apparent power of the motor. f. Determine the torque developped by the motor g. Determine the nominal slip of the motor

six poles three-phase squirrel-cage induction motor, connected to a 50 Hz three-phase feeder, possesses a rated speed of 975 revolution per minute, a rated power of 90 kW, and a rated efficiency of 91%. The motor mechanical loss at the rated speed is 0.5% of the rated power, and the motor can operate in star at 230 V and in delta at 380V. If the rated power factor is 0.89 and the stator winding per phase is 0.036 Ω d. Determine the current absorbed at the stator if the windings are connected in delta e. Determine the apparent power of the motor. f. Determine the torque developped by the motor g. Determine the nominal slip of the motor

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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