Magnetic Component Design for Split Duty Cycle Coupled Multi-phase Boost-Buck Converter

The coupled boost and buck cascaded converter has inductors at the input and output ports of the converter, which makes it well suited for bidirectional battery charging applications where accurate current control and low ripple currents are required. This paper proposes magnetic component sizing and design methodology of a novel split duty cycle coupled multi-phase variant of the cascaded boost-buck converter, suitable for bidirectional operation where the low voltage port has high current, requiring a multi-phase buck stage. The paper covers (a) split duty cycle converter operation principle using coupled inductors and (b) magnetic component design and selection guidelines. The selected magnetic component used in coupled inductor is validated by simulation and experimental results.