Considerations of the Magnetic Field Uniformity for 2-D Rotational Core Loss Measurement

Rotational core loss data are required for the design and optimization of electrical machine. In this paper, a comprehensive investigation of six typical 2-D rotational magnetizers is given based on 3-D FEM dynamic simulation, considering sample eddy current effect. Particular attention is paid to the magnetic field uniformity of the measured sample, mainly referring to the vibration of magnetic flux density B and distribution of z-component magnetic field intensity Hz in the measurement region. Then, a new 2-D double-yoke vertical magnetizer with ultra-thin steel sheet of 0.05mm, which permits one to conduct the 2-D rotational magnetic measurement up to 2 kHz, is designed, simulated and constructed, The magnetic concentration and shielding are performed to strengthen the magnetization ability and improve the magnetic field uniformity of the sample. The accuracy of this magnetizer is verified by comparing experimental results with the data from standard Epstein frame. Both the alternating and 2D rotational magnetic properties of non-oriented (NO) steel B35A210 are systematically measured and characterized at a broad range of frequency and B.