Inductance of A-C magnets from simple models

The inductance of an a-c magnet is a function of its coil as well as its magnetic structure. Hence, if the total equivalent permeance of the magnetic field is known, the inductance can be obtained from the equation $L = N^{2} p_{eq} (10^{-8}) eqno {hbox{(1)}}$ where L = inductance, henrys N = series turns in the coil peq = equivalent permeance, lines/ampere Because computing the permeance of even very simple fields is at best a laborious process, the permeance is generally most easily obtained from experimental tests on models. This paper describes a method in which the field of an a-c magnet is divided into a particular set of hypothetical components which can be simulated electrically with simple models. The permeance of each component field is obtained from a model which suits the component field, and the several permeances so obtained are superimposed to yield the permeance of the original field.