A Three-Port Five-Channel Converter With High Output Current and Wide Voltage Range

This article proposes a three-port converter utilizing five power channels. Four of these channels form an output-parallel multiphase interleaved LLC structure, designed to transfer the energy to high power and current loads. The other channel operates as an equivalent multilevel dual active bridge (DAB) converter, connects to a wide voltage range load and allows for bidirectional energy flow. The four LLC channels efficiently transfer power while significantly enhancing the soft-switching capability of the DAB channel. In addition, the high-voltage side switches operate with half voltage stress, which not only mitigates the challenges associated with soft-switching but also improves the overall reliability of the converter. To further optimize the performance, a modulation method is introduced for the proposed converter, enabling phase-shift control of four LLC channels and reducing the peak current in the DAB converter. Finally, a 3-kW prototype is developed to validate the effectiveness of the proposed converter. One port of the prototype has half of the input voltage stress, enabling it to handle a high input voltage of 750 V, while another port achieves a wide output voltage range of 40-200 V, and the third port delivers a high output current of 40 A.