Modelling of Nonlinear Magnetic Properties of Current Transformers with Piecewise Bézier Curves

The magnetic properties of iron cores of contemporary electrical devices, such as current transformers, are highly nonlinear. This work proposes a simple modelling method for the nonlinear magnetic properties using piecewise Bézier curves. An anhysteretic curve is modelled with three measured points. Two second order Bézier curves are joined to form a composite curve based on those measured points. The modelled curve was then compared with a measured anhysteretic curve of a commercial electrical steel sheet. The presented results confirm that this approach with piecewise Bézier curves shows high potential to model magnetization curves.