Affiliations: [a] School of Automation, Northwestern Polytechnical University, Xi'an 710072, Shaanxi, China | [b] Electrical Engineering Laboratory of Paris, Paris, France
Abstract: For practical applications, the B-H
curve, namely the magnetization characteristic, of the electrical steel is
essential for the performance evaluation of the electrical machine. The
curve is significantly affected by the manufacturing process of the
electrical steel and the electrical machine. In this paper, a new method to
determine the actual B-H curve of the electrical steel used in switched
reluctance machine (SRM) is proposed based on magnetic equivalent circuit (MEC), where the magnetic path of the machine is divided into five segments.
With the flux-linkage characteristic of the SRM at the aligned rotor
position, the magnetic flux density and magnetic field intensity of the
stator pole are calculated based on Ampere's law and linear interpolation,
and then the B-H curve of the electrical steel is obtained. The accuracy of
the proposed method is evaluated by simulation with finite element method
(FEM), and the method is also applied to determine the B-H curve of the
electrical steel used in a 3-phase 12/8-pole SRM prototype. The simulation
results from FEM and Matlab are compared with those from the experiments in
detail, which verify the validity of the proposed method.
Keywords: Switched reluctance machine (SRM), electrical steel, B-H curve, magnetic equivalent circuit (MEC), finite element method (FEM)
