Question 2 (a) A three-phase 50-Hz four-pole star-connected cage induction motor gave the following testing results: Stator winding resistance per phase Locked rotor test at rated stator current No load test at rated stator voltage 0.75 Ω 100 V, 28 A, 2.8 kW 380 V, 5 A, 2.1 kW Friction and windage losses are negligible. Based on the approximate model, (i) calculate the rated speed and rated torque of the machine; and (ii) calculate the starting torque of the machine at direct online starting. (b) Briefly explain why induction machines are preferred over de machines in most industrial application.

Question 2 (a) A three-phase 50-Hz four-pole star-connected cage induction motor gave the following testing results: Stator winding resistance per phase Locked rotor test at rated stator current No load test at rated stator voltage 0.75 Ω 100 V, 28 A, 2.8 kW 380 V, 5 A, 2.1 kW Friction and windage losses are negligible. Based on the approximate model, (i) calculate the rated speed and rated torque of the machine; and (ii) calculate the starting torque of the machine at direct online starting. (b) Briefly explain why induction machines are preferred over de machines in most industrial application.

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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