Asymmetrical duty-cycle control of a novel multi-port CLL resonant converter

In this study, a novel multi-port CLL resonant converter with an asymmetrical duty cycle control is analyzed. The proposed asymmetrical duty cycle manages the output voltage for various load conditions. Series connected transformers at the secondary side enable to split the power in each port and reduce the voltage stresses on the switches compared to the parallel connected transformers. Even under the unbalanced input conditions, the current sharing between ports is preserved because of the magnetizing inductance of the CLL resonant converter that can be as large as needed. In order to investigate the proposed control in the converter, two different isolated DC sources and a variable load are used. The converter operation is tested at 120 V inputs with the output of 200 V at a full power of 1 kW with a maximum efficiency of 97.4%. The experimental results show that the multi-port CLL resonant converter with the proposed controller is an appropriate topology for sustainable energy platforms which are supplied by different type of energy sources such as photovoltaic, fuel-cell, wind, etc., at various power capacities.