Method for Measuring Iron Losses in Elliptically Polarized Magnetic Fields

Abstract

A method for measuring iron losses in elliptically polarized magnetic fields has been devised. The fields are produced in a laminated one-inch cubic specimen by the superposition of two mutually perpendicular magnetic fields whose magnitudes and time phase angles can be varied. Orthogonal fields are obtained by the use of two “C” cores with air gaps large enough to contain the specimen. The flux density is ascertained from the voltages induced in two coils wound on the specimen with axes parallel to the two field components. The iron loss is determined by measuring the heating transient in the specimen. In addition, the anisotropy in losses due to alternating magnetic fields can be determined as a special case of elliptically polarized field excitation. The loss data obtained by this method agrees with the results given by the standard Epstein test to within 15%.