Quasistatic measurements for hysteresis modeling

In order to validate and test the correctness of hysteresis models used in the simulation of soft magnetic materials (electrical steel), one has to di spose of experimental data describing the hysteresis behavior of the materi al e.g., measurements under slow time varying excitation conditions in orde r to reduce the dynamic effects to a strict minimum. Based on measured loop s (1-5 Hz) on nonoriented 3% SiFe alloys, and starting from the statistical loss theory of Bertotti, where the total applied field is subdivided into a hysteresis, a classical and an excess field, one can obtain the dc loop o f the material by eliminating the remaining dynamic effects in the laminati on. A comparison between three types of measurements is made, namely, hyste resis loops obtained by extrapolating from dynamic measurements using the s tatistical loss theory, second loops measured under slow time varying induc tion (0,1 Hz)-the influence of the used frequency (0,1-5 Hz) and the used e xcitation wave form (constant dH/dt...constant dH/dt) is examined-and third measured loops obtained from a static (ballistic-like) method. An improvem ent of the quasistatic measurement procedure is proposed, and implemented i n the data-acquisition software for the determination of the material Evere tt function. (C) 2000 American Institute of Physics. [S0021-8979(00)20608-7 ].