5. Circuits need only small step-up/down ratios employ: (a) Inverters (b) Transformer rectifier units (c) auto-transformers (d)none 6. A three-phase induction motor has three pairs of poles and is operated from a 60 Hz supply. Which one of the following gives the motor's synchronous speed? (a) 1200r.p.m (b) 1800r.p.m. (c) 3600r.p.m. (d)1500r.p.m. 7. In a star-connected three-phase system, the line voltage is found to be 200V. Which one of the following gives the approximate value of phase voltage? (a) 67 V (b) 115 V (c) 346 V. (d)400V.

5. Circuits need only small step-up/down ratios employ: (a) Inverters (b) Transformer rectifier units (c) auto-transformers (d)none 6. A three-phase induction motor has three pairs of poles and is operated from a 60 Hz supply. Which one of the following gives the motor's synchronous speed? (a) 1200r.p.m (b) 1800r.p.m. (c) 3600r.p.m. (d)1500r.p.m. 7. In a star-connected three-phase system, the line voltage is found to be 200V. Which one of the following gives the approximate value of phase voltage? (a) 67 V (b) 115 V (c) 346 V. (d)400V.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter12: Power System Controls

Section: Chapter Questions

Problem 12.5P

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