High Conversion Ratio DC–DC Converters With Reduced Switch Stress

In this paper, a new class of single-switch nonisolated high step-up DC-DC converters with simple topologies is proposed. The proposed topologies utilize a hybrid switched capacitor technique for providing a high voltage gain without extreme switch duty cycle and yet enabling the use of a lower voltage and R_DS-ON MOSFET switch so as to reduce cost, switch conduction and turn-on losses. Other advantages of the proposed topologies include: continuous input/output current, simple structure and control. The principle of operation in continuous conduction mode and discontinuous inductor current mode are analyzed. Experimental results obtained on a 45-W prototype are also presented.