Expandable interleaved high voltage gain boost DC-DC converter with low switching stress

In this paper, an interleaved DC-DC step-up boost converter with high voltage conversion ratio and low voltage stresses on switches and diodes is proposed. The proposed converter has low average current passing through the diodes and switches and low input current ripple as a feature of interleaved converters. The voltage gain of the proposed converter can be increased by adding more diode-capacitor modules; therefore, the proposed converter has expandable structure. In addition, by implementing more diode-capacitor modules, the switching stresses would be more decreased. Also, to evaluate the performance of the proposed converter, it is compared with other similar presented circuits in the literature. The proposed converter is not only able to provide higher voltage gain but also has lower voltage stresses on switches and diodes. Consequently, switches and diodes with low voltage ratings can be selected. Theoretical analysis is provided in this study for each operation mode and the average current through the switches, diodes and inductors, voltage stresses on switches and diodes, voltage gain, and input current ripple are calculated. Finally, to demonstrate the accuracy performance of the proposed converter, a 450-W prototype is implemented practically.