Patent ID: 8836462

Claim:
A transformer, comprising: a housing enclosing therein: a first module including a stationary primary core, wherein the primary core includes a cylindrical outer circumference defining a plurality of axially oriented primary slots; a second module including an annular shaped stationary secondary core, wherein the secondary core includes a cylindrical inner circumference defining a plurality of axially oriented secondary slots, and wherein the first module is assembled into the second module such that said inner circumference is concentrically oriented about the primary core outer circumference; at least one phase primary winding oriented within the primary slots, for coupling to a phase of alternating current input power; at least one phase secondary winding oriented within the secondary slots, inductively coupled to the at least one phase primary winding, for generating a separate phase of alternating current output power wherein the primary and secondary windings are prefabricated before the first module is assembled into the second module.