Improved calculation formula of core losses for laminated silicon steels at high frequency and high flux density

The currently available core losses calculation formulae do not take the impacts of frequency and flux density on the loss coefficients into account at high frequency and high flux density. To solve this problem, we proposed an improved core losses calculation formula. On the basis of the original losses data of several typical laminated silicon steels, in combination with the experimental data of core losses over wide range of excitation frequency carried out by using a novel 3-D magnetic properties testing system, we investigated the influences of eddy current skin effect and the dynamic hysteresis loop on the loss coefficients by employing the improved calculation formula. Then we drew out new curves of core losses, and compared them with the measured data. The results show that the core losses calculated by the proposed formulae have a good consistency with the measured data. The proposed method can improve the computation accuracy obviously, and reduce the maximum error from 35% to 10%. Moreover, it is validated that the loss coefficients should change with frequency and flux density at high frequency and high flux density.