Eddy current modeling of silicon steel for use on SPICE

The relation between the equivalent eddy current field He and the instantaneous flux density rate dB/dt is experimentally obtained for current transformers made of silicon steel. The results show that He is proportional to (dB/dt)^0.6-0.7 in the operating frequency range (~100 Hz) of the current transformers. The ac B-H loop calculated by combining the proposed eddy current model with the Jiles-Atherton model agrees well with the measured data. In addition, this combined model allows magnetic component characteristics using SPICE to be simulated. The simulated secondary voltage waveforms of current transformers are in satisfactory agreement with the measured values