Transformers connected in wye-delta

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Homework Statement


Three single phase transformers rated 100kVA, 13.2kV/2.4KV are connected in wye-delta on a 3-phase, 18kV line.

I need to find the maximum load that can be connected to the transformer bank and the outgoing line voltage.


Homework Equations





The Attempt at a Solution


I am completely stuck, so far I've got:
Voltage across primary is 2.4kV therefore voltage across secondary is 13.2kV
Es=13.2\sqrt{3}=22.86kV?

Any help would be greatly appreciated.

Adam
 
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This can't be right can it? Do you have a 2.4KV transformer connected to an 18KV line?
 
I'm not 100% sure if that's what the question is implying as I'm completely stuck on it.
Thanks for the quick reply though.
 
Well, I don't know how 3 phase transformers are voltage rated, as I haven't studied them. However, if the voltage of a Delta is measured from phase to phase and voltage of a Wye is measured neutral to any phase, then you don't use the factor of sqrt(3).
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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