A Novel Nonisolated Buck–Boost Converter With Continuous Input Current and Semiquadratic Voltage Gain

Abstract

A buck–boost dc–dc converter with semi-quadratic voltage gain is introduced in this article. The proposed converter benefits from continuous input current and common ground characteristic between input–output voltage ports. Due to low ripple input current, the proposed converter is a proper choice for carbon-free power sources such as photovoltaic (PV). Unlike the traditional buck–boost converter, the presented converter offers positive output voltage and large voltage gain without using an extreme duty cycle. In addition, the voltage stresses across the power switches of the proposed converter are very low compared with the output voltage. Hence, power switches with low on-resistance are used in practical implementation, which leads to power loss reduction and efficiency improvement. The performance principles, dc analysis, modeling process, and power loss analysis of the proposed converter are fully described. Finally, a laboratory prototype is implemented so as to evaluate the previously mentioned features of the proposed converter.