Just remember this, a transformer is designed for a purpose and it can
be either a step up transformer or a step down transformer.
Everything else you need to know is here.


Go to this web site to pick up the basic theory:
http://elgersmad.homestead.com/files/resonance/transformer_motor_theory.pdf

Go to this link to understand that it will work:
http://www.gutenberg.org/files/11498/11498-h/11498-h.htm#4

Go to this link for the formula an equations required to design and
build your own:

Notes for an Introductory Course On Electrical Machines and Drives
http://www.egr.msu.edu/~fzpeng/ECE320/ECE320-Notes-Part1.pdf