Dynamical Modeling of Power Converters with Power Semiconductor Filter

"Power Semiconductor Filter (PSF)" has been proposed to replace passive input filter with a semiconductor device. The methodology is based on using a series-pass device (SPD) to control the input current profile of the converter. The operating point of the SPD is regulated at the boundary between the active and the saturation regions by controlling the input impedance of the converter, so that the power dissipation of the SPD is minimized and the overall efficiency is comparable with the conventional passive filter. There is a significant reduction of the physical size. This paper will present the dynamical model of the converter with PSF. The system characteristics will be demonstrated on a 75W, 90V-140V / 24V classical CCM DC-DC buck converter. Experimental results show that the model is valid up to one-fifth of the switching frequency. Moreover, modeling, design, and analysis of the entire system will be presented.