A three-phase non-linear transformer, comprising: a ferromagnetic core formed of at least three core frames each having first, second, and third sections of successive lamination layers, said at least three core frames arranged in a non-linear configuration, each of said at least three core frames comprising a leg section and a yoke section, each of said leg sections combining with a leg section of another core frame to form at least three core legs having substantially circular cross-sections, respectively; and coil assemblies mounted to each of the at least three core legs, said coil assemblies comprising: a secondary winding wound around each of the at least three core legs, respectively; wherein each of said first, second, and third sections of lamination layers is wound successively to form a cross section of lamination layers approximating the shape of a semi-circle wherein the first layer of each section of lamination layers is positioned at an angle of offset from the first layer of adjacent sections, wherein the first section of lamination layers has a trapezoidal shape, the second section of lamination layers has a rhombic shape, and the third section of lamination layers has a trapezoidal shape, characterized in that the first section of lamination layers includes a first outer side and a first inner side on opposite sides of the first section, the first outer side being narrower than the first inner side, and the third section of lamination layers includes a second inner side and a second outer side on opposite sides of the third section, the second outer side being narrower than the second inner side, the first and second inner sides being adjacent to opposite sides of the second section, and in that said coil assemblies further comprise: a primary winding disposed around each of the secondary winding. a ferromagnetic core formed of at least three core frames each having first, second, and third sections of successive lamination layers, said at least three core frames arranged in a non-linear configuration, each of said at least three core frames comprising a leg section and a yoke section, each of said leg sections combining with a leg section of another core frame to form at least three core legs having substantially circular cross-sections, respectively; and coil assemblies mounted to each of the at least three core legs, said coil assemblies comprising: a secondary winding wound around each of the at least three core legs, respectively; a secondary winding wound around each of the at least three core legs, respectively; wherein each of said first, second, and third sections of lamination layers is wound successively to form a cross section of lamination layers approximating the shape of a semi-circle wherein the first layer of each section of lamination layers is positioned at an angle of offset from the first layer of adjacent sections, wherein the first section of lamination layers has a trapezoidal shape, the second section of lamination layers has a rhombic shape, and the third section of lamination layers has a trapezoidal shape, characterized in that the first section of lamination layers includes a first outer side and a first inner side on opposite sides of the first section, the first outer side being narrower than the first inner side, and the third section of lamination layers includes a second inner side and a second outer side on opposite sides of the third section, the second outer side being narrower than the second inner side, the first and second inner sides being adjacent to opposite sides of the second section, and in that said coil assemblies further comprise: a primary winding disposed around each of the secondary winding. a primary winding disposed around each of the secondary winding.