Q16/ The star-connected rotor of a 3-phase induction motor has a resistance and standstill reactance 0.4 Q/phase respectively. The e.m.f. induced between the slip rings at standstill is 80V, the stator being connected to a normal supply voltage. Find the rotor current and power factor at starting when the rings are (i) short-circuited (ii) joined to star-connected resistance of 52/phase. Ans [18.25A , 0.16 ,7.76 , 0.91]

Q16/ The star-connected rotor of a 3-phase induction motor has a resistance and standstill reactance 0.4 Q/phase respectively. The e.m.f. induced between the slip rings at standstill is 80V, the stator being connected to a normal supply voltage. Find the rotor current and power factor at starting when the rings are (i) short-circuited (ii) joined to star-connected resistance of 52/phase. Ans [18.25A , 0.16 ,7.76 , 0.91]

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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