Three-phase 460-hp, 415 V, 4-pole, 50 Hz induction motor is operating at overvoltage of 480 V and reduced load of 80% of the rated value and draws a line current of 624.06A, The losses at these operating conditions are as follows: The stator conductor loss is 12.6kW, the rotor conductor loss is 10.4kW, the core loss is 11.00KW; and rotational losses is 4.129 kW. Sketch the power flow diagram, enter the known values, and determine (a) 1oko speed (b) shaft output torque (c) developed mechanical torque in Nm. (d) input power to the stator, (1) uie mper power factor. Do only part (a), (b) & (c)

Three-phase 460-hp, 415 V, 4-pole, 50 Hz induction motor is operating at overvoltage of 480 V and reduced load of 80% of the rated value and draws a line current of 624.06A, The losses at these operating conditions are as follows: The stator conductor loss is 12.6kW, the rotor conductor loss is 10.4kW, the core loss is 11.00KW; and rotational losses is 4.129 kW. Sketch the power flow diagram, enter the known values, and determine (a) 1oko speed (b) shaft output torque (c) developed mechanical torque in Nm. (d) input power to the stator, (1) uie mper power factor. Do only part (a), (b) & (c)

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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Discuss the behaviour of an induction motor when it is rotating at synchronous speed.
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A 3-phase, 60 Hz induction motor has two poles. If the slip is 2% at a certain load, determine the synchronous speed, the speed of the rotor and the frequency of the induced e.m.f.'s in the rotor.
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Q.14. What is slip in an induction motor? Q.15. What is the value of slip at start in an induction motor?
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