Quadratic Boost DC-DC Converter With High Voltage Gain and Reduced Voltage Stresses

This paper proposes a quadratic boost dc-dc converter with a high voltage gain and reduced voltage stresses. The conventional quadratic boost converter has a limited voltage gain, which is not suitable for high-step-up applications with various microgrids. In the proposed converter, to improve the voltage gain beyond that of a quadratic converter, a coupled inductor is adopted. Additionally, passive clamping circuits are applied to reduce the high voltage stresses caused by leakage inductance of the coupled inductor. Hence, additional power losses from the snubber circuit do not occur, and low-voltage-rating switching devices can be utilized for the main switch and output diode. Moreover, the reverse-recovery problem of the output diode can be alleviated by the leakage inductance. Therefore, the total power efficiency is improved. The theoretical analysis of the proposed converter is verified with a 300-V, 120-W prototype.