Q17/ A 1100V, 50Hz, delta-connected induction motor has a star-connected slip ring rotor with a phase transformation ratio 3.8. The rotor resistance and standstill leakage reactance are 0.01292 and 0.2592 per phase respectively. Neglecting stator impedance and magnetizing current, determine (i) the rotor current at start with slip rings shorted (ii) the rotor power factor at start with slip rings shorted (iii) the rotor current at 4% slip with slip rings shorted 2 Tutorial Sheet (1) (iv) the rotor p.f. at 4% slip with slip rings shorted (v) the external resistance per phase required to obtain a starting current of 100 A in stator supply lines. Ans [1157A 0.048 lag 742 3A 077 070791

Q17/ A 1100V, 50Hz, delta-connected induction motor has a star-connected slip ring rotor with a phase transformation ratio 3.8. The rotor resistance and standstill leakage reactance are 0.01292 and 0.2592 per phase respectively. Neglecting stator impedance and magnetizing current, determine (i) the rotor current at start with slip rings shorted (ii) the rotor power factor at start with slip rings shorted (iii) the rotor current at 4% slip with slip rings shorted 2 Tutorial Sheet (1) (iv) the rotor p.f. at 4% slip with slip rings shorted (v) the external resistance per phase required to obtain a starting current of 100 A in stator supply lines. Ans [1157A 0.048 lag 742 3A 077 070791

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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