A 240 V delta-connected 60 Hz synchronous motor has a reactance of 2.5 and negligible armature resistance. The friction losses are 1300 W and the core losses are 1000 W. The shaft is supplying a 11.2 kW load and the power factor of the motor is 0.85 leading. (i) Find the input power. (ii) Determine the line current and the armature current. (iii) Find the excitation voltage. (iv) Draw the phasor diagram for this condition.

A 240 V delta-connected 60 Hz synchronous motor has a reactance of 2.5 and negligible armature resistance. The friction losses are 1300 W and the core losses are 1000 W. The shaft is supplying a 11.2 kW load and the power factor of the motor is 0.85 leading. (i) Find the input power. (ii) Determine the line current and the armature current. (iii) Find the excitation voltage. (iv) Draw the phasor diagram for this condition.

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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