Magnetic core for transformer or inductor - has elliptical or quasi-elliptical cross=sections to combine advantages of circular and square shapes

摘要

The quasi-elliptical core is constructed from rectangular plates, which have a uniform depth, but varying widths and lengths. The ends of all the plates lie on or just within a perimeter defined by two semicircles of radius, a/2, and two straight lines of length, b-a, which join the ends of the semi-circles. The preferred ratio between b and a is between 1:1.3 and 1:1.7. - The elliptical version has a long axis b and a short axis a. The preferred ratio between b and a is similar to that of the quasi-elliptical version, but may be as low as 1:1.05 or as high as 1:2.