Modeling, design, and performance analysis of a Y-source DC-DC converter under limitations of hardware and leakage inductances

Abstract

The widespread of renewable energy sources often requires DC-DC power converters with higher operational flexibility and voltage gain capability. The Y-source converter offers significant features to fill this demand, but its performance can be negatively affected by coupled-inductor leakage inductances. This paper presents simplified models for the Y-source DC-DC converter (YSDC) that, although not directly including the presence of leakage inductances, offer a satisfactory description of how the converter operates in terms of its steady-state behavior, small-signal dynamics, and estimation of power losses. These models allow for a comprehensive analysis of how non-ideal components in the converter affect the determination of the YSDC voltage gain and efficiency and allow one to identify the most interesting design alternatives to satisfy the current and voltage stress constraints placed on the converter power switches, thus excluding undesired converter design alternatives. Experimental results with a 280 W real converter, using coupled-inductor with leakage inductances, present results similar to those of switched circuit simulations and the derived models, thus confirming that the simplified models present satisfactory adherence to the real converter performance over the majority extent of the maximum duty cycle.