Improved Reliability and Performance Evaluation of Switched-Boost Multiport Converter Using Time-Multiplexing Control

In this article, a novel bidirectional boost-side interleaved switched boost (BBSISB) multiport converter is proposed. The boost-side interleaving (BSI) of the converter improves its performance in terms of input current ripple and reliability in medium-power applications. The BSI reduces the input current ripple (i.e., zero at 50% of duty ratio), and it also provides an open circuit (OC) switch fault-tolerance index (FTI) of 100% at the load end. The switched-boost action topology uses time multiplexing of boost and buck switches to produce regulated voltage at output ports, whereas the boost-side phase interleaving provides the paralleling of large input boost current with reduced current ripple. The bidirectional capability of the converter enables the power flow from the battery to the load end in the absence of an input supply. The performance analysis of the proposed converter with respect to switching loss, conduction loss, FTI, current ripple, and cost is performed and compared with similar converters. An experimental setup of the BBSISB multiport converter is developed in the laboratory with a constant-current, constant-voltage (CC-CV) mode of charging of the battery to verify the derived analytical results.