Characteristic and performance analysis of SRM with actual B-H curve of electrical steel

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.