Choice of segments in the B=B(H) approximation using spline functions

Abstract

In this paper we show how the choice of selected points for building the basic curve of the first magnetization can influence the accuracy. The presented approach enables one to simply build curves B = B (H) and μ = μ(H) using the cubic spline functions C(2). All procedures are practically given analytically, so that by having good information on the magnetic field at the beginning and at the end of a treated curve given by the couple (H,B), we obtain the curve twice differentiable. It is important to mention that we do not need to have many date points to construct all presented curves. Having the approximation of the curve B = B (H) and using the software package ‘CURVES’, it is possible to get much more information about the maximal value of the relative magnetic permeability, the differential permeability and the approximation of the curve μ = μ(H). This powerful software can be used separately for each calculation or, as the complete program.