Making Three Phase Transformer from Single Phase Ones

Why not just use three single phase transformers?

Because it's a "EE 360 (Semester 121) Design Project at KING FAHD UNIVERSITY"

Due on the 22nd of December.

'...There could be up to 100 different solutions to this problem.....'

.

100? ...or 200?

Thank you all for your help, the the problem is when I ask my instructor for some help, he says it's you project and I can get nothing from him. your help is really appreciated.

OK... then here is a hand...

Basically... a three phase transformer is built how?

Once you answer that... how would you do it with individual transformers?

can't be done........you can use 3 phase to make a single phase work but not the other way around

Hey Fred...

Sure ya can.. Re read his original question.

Stating anything more would give the OP the info I want him to figure out for himself.

What is your bike? I ride a 2001 HD Heritage Softail Springer.

ya got me on that one I didn't read it right

There are probably less than two dozen ways, even including wrong ones, of hooking up three single-phase transformers. (Star, delta, phase reversals if they even matter...)

Has anyone looked at http://www.mediafire...........

A 2400/240 V TRANSFORMER SHOULD NEVER BE CONNECTED AS A 2640 V TO 240 V AUTOTRANSFORMER. There is too much risk that 2640 W will get on the 240 V.

There is only one way that I know that these transformers can be connected, and that is making some assumptions that are usually incorrect. If I'm wrong, please correct me.

Assume that the 2640 volt is line to ground at 0 phase angle.
Connect the 2400 V transformer as an autotransformer with the 240 volt grounded

Assume that the 120 volt is at 120 degrees.
Connect the primary of one 120 volt transformer across the 120 volt.

Assume that the other 120 volt is at 240 degrees.
Connect the primary of the other 120 volt transformer across the 120 volt.

Connect all 240 volt windings in delta observing phase.
You now have three phase 240 volt with one corner of the delta grounded.

The problem is that he didn't mention that we have 3-phase supplies, with your assumption it should work. That is why I am wondering because we didn't study a thing like this before. Thank you all for your comments.

Am I loosing my sight? I see only one way of doing it.

powervirus, let us know what your professor says is the answer.

Good Luck
Carl

Powervirus, in the Philippines it has been our practice for a decade to "bank" Three(3) single-phase transformers of identical characteristics say turns ratio, % impedance, minimum coreloss and copper loss in our distribution system at 13.2KV primary and 240V secondary. we connected these 3 single-phase transformers at Primary as WYE (neutral grounded) and at secondary as DELTA(corner grounded). We do this in our country for flexibility and inter-changeability to use same transformers to supply power to our consumers either in three phase or single-phase. And also to use only two transformers in case one of the 3 bugs downed re-connected as open-delta.Or an option to use only 2 transformer for the present, then buy an additional one unit as the load increases. In our power transmissions at 69KV and a above we have a factory connected three-phase transformers.F.Y.I.