Influence of Bending Stress on Magnetic Properties of 3-Phase 3-Leg Transformers With Amorphous Cores

This paper mainly explores the influence of bending stresses on the magnetic characteristics of three-phase amorphous transformers. Different types of core structures, including C-shaped and toroidal cores, are considered for a comparison of magnetic properties using VSM, XRD, and SEM. Among all specimens, those taken from the limb plane and the rectangular corner of a C-core have the lowest and highest coercivities, respectively. In addition, the crystalline property of Fe and α -Fe of rectangular cores is stronger than that of toroidal cores. Subsequently, the properties of magnetic loss and magnetic anisotropy are investigated. The experimental results of three-phase amorphous core transformers with a capacity of 100 kVA demonstrate that the toroidal core transformer has better magnetic characteristics in terms of lower core loss and exciting power than conventional C-core transformers.