A 480W 40-to-60VIN Quadrangle Controlled Four-Switch Buck-Boost Converter with Zero-Freewheeling and Reverse Inductor Current Supply Techniques Achieving 99% Peak Efficiency

This paper presents a quadrangle controlled four-switch buck-boost(FSBB) converter with zero-freewheeling and reverse inductor current supply techniques. With the proposed zero-free-wheeling technique, the ripple of inductor current has been significantly reduced, and freewheeling current has been virtually eliminated, thereby improving light load efficiency. Furthermore, utilizing the inductor reverse current to generate the required 5 V power supply for driving the power transistors, which significantly improves the efficiency of the FSBB converter. Simulation results show that the FSBB converter achieves a peak efficiency of $\mathbf{9 9 \%}$, maintaining efficiencies above $\mathbf{9 2 \%}$ across both full load and input ranges.