Boost topology based multi-output converters

Abstract

Multi-output converters with single input source are currently studied as an alternative to conventional DC-DC topologies in order to improve power density in low power applications. The paper reviews three different ways in which a boost topology can be customized to supply multiple outputs. The first way uses a charge share approach using individual switches to distribute inductor energy to different capacitors. A second method of creating a MOC combines two converters with similar front end to generate two outputs using only one controlled switch. Using this method, a Boost converter can be combined with SEPIC, Cuk, and current source converter (CSC) topologies. A third method uses time-multiplexing of switches to produce two regulated outputs and is referred to as Switched Boost approach. This method uses relatively less number of switches and allows regulation and control of all the outputs. Practical application of switched boost approach based MOC is reported this work. The time-multiplexing approach is applied to a renewable power converter system to interface a solar panel, a battery, and home loads to produce a 12 Vand a 48 V bus. The 12 V bus is interfaced to battery and capable of optimally charging the battery in CC-CV mode. The converter is demonstrated to operate with solar panel as it supplies the 48 V loads and charges a battery. Similarly, when solar power is not available, the converter automatically goes to a mode in which the battery supplies the 48 V loads.