A Buck-Boost DC/DC Converter with High Efficiency Suitable for Renewable Energies

In this paper, a non-isolated buck-boost dc/dc converter with only one switch is presented. The proposed converter consists of one switch in the input side ( ), four inductors, four diodes, six capacitors and a capacitor in the output side ( ). In fact, the combination of the inductor, diode and capacitor leads voltage level is increased. Actually, the voltage stress on power switch is decreased for higher power limits at various duty-cycles by combining these components. Therefore, conduction losses can be reduced by using a switch with lower resistance . Another advantage of the proposed converter is that the normalized voltage stress on diodes is low. As a result, the efficiency of proposed converter is high. In order to investigate the competences of the proposed converter, comparison results with other structures are provided. The principle of operation, theoretical analysis and the experimental prototype of proposed converter in about 120 W with operating at 25 kHz are provided.