Asymmetrical Duty-Cycle and Phase-Shift Control of a Novel Multiport CLL Resonant Converter

Abstract

In this paper, a novel multiport CLL resonant converter with a phase shift and asymmetrical duty-cycle control is analyzed. The power flow can be maintained with the phase shift between ports, whereas the asymmetric duty cycle manages the output voltage at the load terminals. Series connected transformers at the secondary side enable to split the power in each port and reduce the voltage stresses on the switches compared with the parallel connected transformers. Even under the unbalanced input conditions, the power flow between ports can be managed by the central control without any need for communication devices. In order to investigate the power distribution in each port, two different isolated dc sources and a variable load are used. The converter operation is tested at 40, 80, or 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 multiport CLL resonant converter with the proposed controller is an appropriate topology for sustainable energy platforms, which are supplied by different types of energy sources, such as photovoltaic, fuel cell, wind, and so on, at various power capacities.