Estimation of DC Hysteresis Property Using Nonlinear Eddy Current Analysis Considering Hysteretic Property

The DC hysteresis property should be considered in the nonlinear eddy current analysis for accurate hysteresis loop and iron loss calculation of iron cores composed of silicon steels. However, the DC hysteresis property is usually measured at ultra-low frequency (e.g., 0.01 Hz) and it is quite difficult due to very low signal to noise ratio. In this paper, we proposed a method to derive the DC hysteresis property from the AC hysteresis property measured at 20 Hz, which is relatively easy to be measured. The eddy current effect in the 20 Hz hysteresis loop is removed by using an iterative eddy current analysis considering hysteretic property. The estimated DC hysteresis property obtained from the proposed method are compared with those obtained from a conventional estimation method. Finally, the obtained DC hysteresis property are used in the AC hysteresis loops and iron losses calculation (50∼1 kHz) of a non-oriented silicon steel and compared with the measured ones. The hysteresis loops and iron losses can be well represented.