A 750 kW, 3300V, 50 Hz, wound-rotor three-phase induction motor with a star-connected stator winding has a star-connected rotor winding with effective stator/rotor turns ratio of 3.6. The rotor resistance and rotor leakage inductance are 0.0296 2 and 1.7 mH respectively. The stator winding resistance, the stator leakage inductance, and the mutual inductance can be neglected. (a) Calculate the stator current and power factor at a slip of 0.03. (b) Calculate the torque developed at this load. (c) Calculate the stator current and power factor when starting with rated voltage and with the slip-rings short-circuited.

A 750 kW, 3300V, 50 Hz, wound-rotor three-phase induction motor with a star-connected stator winding has a star-connected rotor winding with effective stator/rotor turns ratio of 3.6. The rotor resistance and rotor leakage inductance are 0.0296 2 and 1.7 mH respectively. The stator winding resistance, the stator leakage inductance, and the mutual inductance can be neglected. (a) Calculate the stator current and power factor at a slip of 0.03. (b) Calculate the torque developed at this load. (c) Calculate the stator current and power factor when starting with rated voltage and with the slip-rings short-circuited.

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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