Permanent Magnet (De-) Magnetization and Soft Iron Hysteresis Effects – A comparison of FE analysis techniques

A.M. Michaelides, J. Simkin, P. Kirby and C.P. Riley

Abstract – The paper describes advanced Finite Element Analysis solvers for the treatment of material magnetization. The prediction of hysteretic behaviour in soft ferromagnetic materials is outlined, demonstrating how remanent forces and hysteresis loss can now be accurately quantified. Results from analysis of a hysteresis motor and brake demonstrate the usefulness of the new algorithm in the design of such highly specialized devices. Details of modelling the magnetization of hard magnetic material sections are also presented, along with their subsequent in-service de-magnetization in an electrical machine, as a result of high reverse currents.