J. Phys. IV France 08 (1998) Pr2-561-Pr2-565
Measurement and analysis of magnetic fields on the surface of grain-oriented silicon steel sheetA.J. Moses
Wolfson Centre for Magnetics Technology, School of Engineering, University of Wales Cardiff, P.O. Box 687, Cardiff CF2 3TD, U.K.
Grain oriented, 3% silicon steel sheet is used in motors and transformer cores where an accurate knowledge of its magnetic properties is needed for design calculations. The magnetic field distribution on the sheet surface is of fundamental importance in assessing its overall magnetic properties. The magnetisation often is not always along the rolling direction and the field H and flux density B need not be co-linear leading to errors in measurement of field calculations. The angle between B and H varies with sheet width which may be attributed to demagnetising factors which are not taken into account in magnetic anisotropy modelling for FEM applications. This paper reports results of an investigation of the effect of strip width, peak flux density and direction of magnetic field on the locus of flux density throughout the magnetising cycle. The flux density varies in direction considerably during the cycle and it is shown that this can be related to the corresponding variation of demagnetising field. The paper attempts to identify the influence of the demagnetisation factor so that the results can be related to local magnetisation conditions in the limbs and corners of a transformer.
© EDP Sciences 1998