Step-up switching-mode converter with high voltage gain using a switched-capacitor circuit

Abstract

A new circuit is proposed for a steep step-up of the line voltage. It integrates a switched-capacitor (SC) circuit within a boost converter. An SC circuit can achieve any voltage ratio, allowing for a boost of the input voltage to high values. It is unregulated to allow for a very high efficiency. The boost stage has a regulation purpose. It can operate at a relatively low duty cycle, thus avoiding diode-reverse recovery problems. The new circuit is not a cascade interconnection of the two power stages; their operation is integrated. The simplicity and robustness of the solution, the possibility of getting higher voltage ratios than cascading boost converters, without using transformers with all their problems, and the good overall efficiency are the benefits of the proposed converter.