Patent ID: 7502723

Claim:
A computer-implemented method of modeling the ferromagnetic core of an inductor or transformer in a circuit simulator, the method comprising: the computer obtaining upper and lower branch functions for the major hysteresis loop from memory; obtaining an initial magnetization path as an average of the upper and lower branch functions; determining using the computer, symmetric minor hysteresis loops as the upper and lower branch functions vertically translated by a constant for each specific symmetric minor hysteresis loop; and constructing using the computer, asymmetric minor hysteresis loops as an extension of a minor symmetric hysteresis loop when such a minor loop exists, otherwise a function bound between the branch of the minor hysteresis loop containing the turning point and a basis function composed of the initial magnetization path for one sign of H and the major loop translated by the remnant magnetization flux density for the other sign of H, using the constructed asymmetric minor hysteresis loops for circuit simulation of the inductor or transformer in the circuit simulator, and displaying a result of the circuit simulation.