The magnetic properties and loss characteristics of oriented silicon steel sheets exhibit significant deviation under stress. The traditional loss separation model generally overlooks the impact of mechanical stress on the loss characteristics, resulting in calculation errors. In recent years, most studies on the loss characteristics of oriented silicon steel sheets under mechanical stress have focused on qualitative analysis, with only a few studies making quantitative improvements to the loss separation model. This paper develops an improved loss separation model based on the traditional loss separation model by introducing stress terms into the hysteresis loss and excess loss.

Firstly, measurements from a single sheet tester with unidirectional stressing are utilized to analyze the stress dependency of the loss characteristics of the oriented silicon steel sheets. The experimental results demonstrate a significant enhancement in loss under compressive stress while exhibiting a slight decreasing trend under tensile stress. The magnetization mechanism in ferromagnetism explains the variation of the loss characteristics under mechanical stress. Secondly, the hysteresis loss and excess loss under stress are calculated based on the Bertotti traditional loss separation model. Since the stress component is not introduced into the hysteresis loss in the traditional loss separation model, the effect of stress on the hysteresis loss is only reflected by the hysteresis loss coefficient, leading to a significant error in the calculation of the hysteresis loss under stress. Although the excess loss parameter ${{V}_{0}}$, currently expressed by a constant coefficient, embodies the effect of stress, it fails to capture the effect of the applied mechanical stress on the losses of each magnetic induction intensity. Consequently, computational inaccuracies arise when employing the Bertotti traditional loss separation model.

Based on the correlation between parameters ${{V}_{0}}$ in excess loss, hysteresis loss, and stress, the traditional separation formula for losses is improved by introducing stress components into the excess loss parameters ${{V}_{0}}$ and hysteresis loss. An improved loss separation model is established and verified by varying the frequency of excitation and the type of oriented silicon steel sheet. The results indicate that the improved loss separation model can accurately separate and calculate the losses of oriented silicon steel sheets under different stresses while maintaining a remarkable precision level.

Experimental measurement and calculation analysis are performed, and the conclusions are as follows. (1) The excess loss parameter ${{V}_{0}}$ is correlated with stress, and incorporating the stress component into the excess loss parameter can effectively mitigate the calculation error caused by stress in the traditional loss separation model. (2) An improved loss separation model is proposed based on the traditional mode by incorporating the excess loss and hysteresis loss into stress-related functions. (3) The improved loss separation model is confirmed through testing with different frequency excitations and oriented silicon steel sheets, demonstrating its ability to accurately separate losses under different stresses.