See transformer mainly used for step up purpose are of the
detal-star connection,the advantage is that in the seconary
for step up the insulation req is lessa s the voltage is
57.7 of actual vaue in secondary.So consdier ur question
now? is it advantageous.Transformer designs are done not
merely on load,but the winding
insulation,oil,insulation,cooling,etc are also important.