Can any one help me to sovle this electrical problem?

Question

The design requirements of an 11000 V/400 V, 50Hz, single phase, core-type transformer are: approximate e.m.f /turn is 15V; maximum fulx desity 1.5 T, Find suitable number of primary and secondary turns, and the net cross-sectional area of the core.

Answer 1

Well, If I had your textbook, I'd take a shot at it, but I am not an EE, so without your textbook I don't really want to bother researching the answer, but one hint, I think:

"approximate e.m.f /turn is 15V",  "50Hz" and "maximum flux density 1.5 T"

is probably enough information to determine the cross sectional area of the core of an ideal transformer.

Check out Faraday's Law (for a start, but I think you'll need more than just that) or you could use the "Transformer universal EMF equation" in the box on the Wikipedia Transformer page. which gives an area of 0.045, I'm not sure what units, but I assume m² since T is  weber per square meter

Answer 2

you told us what the number of turns are, 15 volts/turn

which gives you a primary of 11000/15 or 733 turns, and a secondary of 400/15 or 27 turns.

You did not specify a power level, which will determine the size of wire used, which will determine the cross-sectional area.

.

Answer 3

Try it at 10

then 5

then 15

And finally 27, done at intervals, and then when you get a good reading on the meter, use whatever pattern you noticed to adjust for the number of rotations.

At least that's what I'd do.

Answer 4

The secondary of a 750 KVA, 11000/ 400 V, 50 Hz transformer has 160 turns. the area of cross section of the core is  100 cm2