QUESTION 2 A 3-phase, 4-pole, star connected, 415 V, 50 Hz, induction motor has the following T equivalent circuit parameters: R = 0.4 2, R2= 0.56 2, X, =X2= 1.05 N, and Xm= 47.92 2 (R. can be ignored) The total friction, windage, and core losses may be assumed to be constant at 700 W, independent of load. a) Calculate the starting internal torque and the corresponding stator current. b) Determine the maximum internal torque and the corresponding rotor speed. Sketch the torque versus speed curve for 415 V, 50 Hz operation, using the results of a) and b). c) d) Calculate the output torque and the output power at slip 0.025. Show that in the limit of negligible stator winding resistance R1, the torque versus slip expression can be written as 27 T = - max ST max ST max where Tmax is the maximum internal torque, and sTmax is the slip at the maximum torque.

QUESTION 2 A 3-phase, 4-pole, star connected, 415 V, 50 Hz, induction motor has the following T equivalent circuit parameters: R = 0.4 2, R2= 0.56 2, X, =X2= 1.05 N, and Xm= 47.92 2 (R. can be ignored) The total friction, windage, and core losses may be assumed to be constant at 700 W, independent of load. a) Calculate the starting internal torque and the corresponding stator current. b) Determine the maximum internal torque and the corresponding rotor speed. Sketch the torque versus speed curve for 415 V, 50 Hz operation, using the results of a) and b). c) d) Calculate the output torque and the output power at slip 0.025. Show that in the limit of negligible stator winding resistance R1, the torque versus slip expression can be written as 27 T = - max ST max ST max where Tmax is the maximum internal torque, and sTmax is the slip at the maximum torque.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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