Mitigation of inductor loss based on minor-loop hysteresis characteristics

Owing to the progress of low saturation voltage and high speed switching characteristics on the power semiconductor devices, conversion efficiency of the power converters have been increased. On the contrary, the power loss dissipated on the passive component, such as inductors and capacitors, becoming relatively larger. Hence, the increasing of conversion efficiency much higher than 96% is getting harder. The latest research authors have reported shows that more that half amount of the loss on the single-phase PWM inverters is dominated by the loss on the AC filter inductors and the high-frequency transformers. From above point of view, it is evident that discussion regarding loss minimizing method on the passive components, especially the inductors, is essential. In this paper, loss generation process on the AC filter inductor used on the high-frequency switching converter is reviewed. It is pointed out that the minor-hysteresis-loop characteristics on the magnetic core plays an important role of loss dissipation of the inductor. The loss characteristics of the filter inductor on the buck-chopper circuit are studied. Also, influence of modulation method to the loss characteristics of the AC filter inductor on the single-phase PWM inverter is also measured.