Coupled Inductor Based Non-Isolated High Conversion Ratio Boost Extender

A coupled inductor based non-isolated boost extender with high conversion ratio is presented. The topology features higher power density due to the lower physical inductor cores count, with similar efficiency and component stresses as a conventional boost extender. Topology analysis, and its suitability for multiple extension inductor coupling is shown, coupling coefficient impact on the converter performance, and a short design guide is presented. An analysis and design of coupled inductor is demonstrated, and experimental prototype of 200W is developed and tested in the laboratory. The experimental prototype operated at maximum efficiency of 94.4% providing step up conversion ratio of 10.5, employing a coupled inductor the size of a single inductor of the conventional boost extender converter. The theoretical predictions were found to be in a good agreement with experimental results.