2-15. 2-15. An autotransformer is used to connect a 12.6-kV distribution line to a 13.8-kV dis- tribution line. It must be capable of handling 2000 kVA. There are three phases, con- nected Y-Y with their neutrals solidly grounded. (a) What must the NC/NSE turns ratio be to accomplish this connection? (b) How much apparent power must the windings of each autotransformer handle? (c) What is the power advantage of this autotransformer system? (d) If one of the autotransformers were reconnected as an ordinary transformer, what would its ratings be?

2-15. 2-15. An autotransformer is used to connect a 12.6-kV distribution line to a 13.8-kV dis- tribution line. It must be capable of handling 2000 kVA. There are three phases, con- nected Y-Y with their neutrals solidly grounded. (a) What must the NC/NSE turns ratio be to accomplish this connection? (b) How much apparent power must the windings of each autotransformer handle? (c) What is the power advantage of this autotransformer system? (d) If one of the autotransformers were reconnected as an ordinary transformer, what would its ratings be?

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

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.56P: Three single-phase two-winding transformers, each rated 3kVA,220/110volts,60Hz, with a 0.10 per-unit...

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