Comparison and analysis of testing methods for magnetic properties of oriented silicon steel sheets

Abstract

The magnetic properties of oriented silicon steels with different thickness of 0.18 mm, 0.23 mm, 0.27 mm, and 0.30 mm in rolling direction and transverse direction were studied using the excitation current method and H-coil method. The magnetic field strength deviation and specific total loss of two methods were compared based on the excitation current method. The magnetic field distribution was analyzed using MagNet finite element simulation, and it was found that the measurement deviation of the excitation current method is mainly determined by the effective magnetic circuit length. The higher the magnetic flux density, the smaller the effective magnetic path length. Therefore, under low magnetic flux density conditions, the actual effective magnetic path length is greater than the specified effective magnetic path length, resulting in high measurement results, while under high magnetic flux density conditions, the measurement results are low. Due to the influence of hysteresis loss, the deviation ratio of the two methods on the total loss is generally smaller than the deviation ratio of magnetic field strength, and the 0.18mm oriented silicon steel is smaller than other thickness oriented silicon steel. Due to the difficulty of magnetization in the transverse direction of oriented silicon steel, the variation trend of magnetic field strength deviation and specific total loss along the transverse direction is significantly different from that along the rolling direction. In addition, a measurement correction strategy was proposed by determining the actual effective magnetic circuit length of the excitation current method, which achieved good results. This work has certain significance for the accurate measurement of the magnetic properties of oriented silicon steel, and is expected to provide important reference for the application of 0.18mm oriented silicon steel.