Evaluation on iron loss of reactor core under high frequency excitation by magnetic field analysis

Due to the continuing progress in power electronics technologies, a drive frequency of electrical machine such as a reactor and a transformer can be changed arbitrarily. Consequently, it is expected that a reactor or a transformer is downsized by higher frequency for saving space. When these electrical machines which have iron core are driven by high frequency, the iron losses of iron core increase by eddy current effects. In general, these electrical machines are designed by taking account of iron loss characteristics obtained from datasheet of electrical steel sheets. However, there is not the guarantee that the loss on datasheet is the same as the loss of actual machine because of the influence of leakage flux, stress and etc. Nevertheless, the actual machine loss under high frequency has been hardly evaluated in conventional research. Therefore, it is necessary that a building factor of loss is evaluated on high frequency excitation.