Simple switched-capacitor-boost converter with large DC gain and low voltage stress on switches

A simple switched-capacitor step-up cell formed by two capacitors and two diodes is inserted in a boost converter in order to get a large dc line-to-load voltage ratio. The output capacitor and output diode of the boost converter are eliminated, their role being taken by the elements of the switching block. The dc gain of the new structure is the same or larger than that of other converters with two capacitors and one inductor. The voltage stress of the transistor and diodes is just the difference between the output and input voltages. In both switching stages, a direct transfer path of energy from line to load is created, increasing thus the energy conversion efficiency. The new hybrid converter represents another solution for the interface between the alternative sources of energy and their loads or grid. The simulation and experimental results confirm the theoretical analysis.