Establishment and Verification of Core Loss Model of Nanocrystalline under Square Wave Excitation

Abstract:
Accurate estimation of core loss plays an important role in the design and optimization of medium and high frequency transformers. The traditional loss calculation formula is usually applied to calculate core loss under sinusoidal excitation. However, the high-frequency transformer usually works under the non-sinusoidal excitation. In order to improve the accuracy of core loss calculation, the traditional loss calculation formula is modified and optimized in this paper. Furthermore, considering the generality of loss formula at different characteristic frequencies, the nonlinearity of coefficient in loss formula is further investigated, and the relationship between model coefficient and frequency is proposed. Finally, the optimized loss model is verified with experimental results, which is proved to be feasible in estimation of nanocrystalline core loss under square wave excitations.