A single switch based integrated DC-DC converter with high step-up gain

Abstract

High voltage gain DC-DC converters as used in photovoltaic, fuel cells and other low-voltage distributed generation system have played a significant role in the large-scale promotion of new energy generation. A high step-up integrated DC-DC converter based on one active switch is proposed in this paper by making use of advantages of the quadratic Boost converter (QBC) and the voltage multiplying modular (VMM). Firstly, VMM was embedded into QBC, and this two modules share the same input DC source and the active switch. And then the output terminals of these two modules were connected in series sharing the same output diode and filter capacitor. The above combination constitutes the newly proposed integrated converter. One attractive performance of this converter is the gain can be not only controlled by the duty ratio but also the turn ratio of the coupled inductor in VMM. In addition, the low voltage stress across the switch can be achieved since the switch is not directly clamped at the high output voltage, which is conducive for optimizing the energy transmission efficiency. The zero input current ripples can be achieved by reasonably configuring the values of the fully coupled inductor as well as the auxiliary inductor. The operation principles and the steady state performances of the proposed converter are verified by the experimental prototype.