Boost-Integrated Phase-Shift Full-Bridge Converter for Three-Port Interface

Numerous modern systems require energy harvesting from multiple sources and the management of energy storage. The adoption of converter topologies specifically tailored for such applications offers great improvement potential over conventional systems. In this paper, two three-port converter topologies are proposed based on the integration of a boost stage into the popular phase-shift full-bridge converter. Each of the proposed converters is able to interface two bidirectional source/storage ports and an isolated loading port. They are specifically interesting due to their ability to achieve zero-voltage switching for a considerable range of operating conditions. Power flow control is performed using two degrees of freedom: duty-cycle and phase-shift of the two switching legs. Analysis of operating modes and component stresses is presented, leading to a discussion of design guidelines. A comparative study involving the proposed topologies and a conventional multi-converter system is conducted. This study formulates the constraints under which each of the three design choices is most profitable. It demonstrates the ability of the proposed converters to achieve significant savings in losses and/or costs for a range of multi-port applications. Experimental 1 kW prototypes are used to demonstrate the functionality of the proposed converters.