Abstract: Based on the unification of loss separation and field separation, the Preisach model was utilized to calculate the static hysteresis losses. An improved method for the parameter identification of abnormal losses was proposed to improve the accuracy of dynamic hysteresis model under single frequency sinusoidal excitation. The parameter extraction was realized based on the measured losses of the oriented silicon steel sheet under different single frequency sinusoidal conditions by the magnetic property measurement system. The field quantity expression corresponding to the abnormal losses under multi-harmonic excitation was constructed, thus the dynamic hysteresis model of oriented silicon steel sheet under arbitrary complex multi-harmonic excitations was proposed. The predicted dynamic hysteresis loops and losses under various working conditions are compared with the measured ones, which verifies the accuracy and generality of the improved model proposed in this paper.