Q5-(A)-Select the correct answer for the alternatives given. 1- he secondary winding of which of the following transformer is always kept close a)- power transformer b)- auto-transformer c)- current transformer d)- distribution transformer 2-In transformer ,the load current at maximum efficiency is equal to rated load current multiplied by PL d)- Pcu a)- Peu PL b)- [ Pcu Pcu Pi 3-which of the following does not change in transformer a)-current b)-voltage c)- frequency d)-all of the above 4-The full-load copper loss and iron loss of transformer are 6400w and 500w respectively. The copper loss and iron loss at half load will be respectively. a)-(3200 w and 2500 w) b)- (1600 w and 1250 w) c)- (1600 w and 5000w ) d)- (3200 w and 1250 w)

Q5-(A)-Select the correct answer for the alternatives given. 1- he secondary winding of which of the following transformer is always kept close a)- power transformer b)- auto-transformer c)- current transformer d)- distribution transformer 2-In transformer ,the load current at maximum efficiency is equal to rated load current multiplied by PL d)- Pcu a)- Peu PL b)- [ Pcu Pcu Pi 3-which of the following does not change in transformer a)-current b)-voltage c)- frequency d)-all of the above 4-The full-load copper loss and iron loss of transformer are 6400w and 500w respectively. The copper loss and iron loss at half load will be respectively. a)-(3200 w and 2500 w) b)- (1600 w and 1250 w) c)- (1600 w and 5000w ) d)- (3200 w and 1250 w)

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 3.58P: A single-phase two-winding transformer rated 90MVA,80/120kV is to be connected as an autotransformer...

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