Analysis of the Interleaved Isolated Boost Converter with Coupled Inductors

This paper analyzes the Interleaved Boost with Coupled Inductors (IBCI) converter, an isolated topology that is suitable for high step-up applications. Two main contributions are given: an exhaustive steady-state analysis and an accurate small signal model. The former allows to derive a closed-form, non iterative, design procedure for the power stage active and passive components. In addition, it reveals an interesting equivalence with an apparently different converter, the Single Active Bridge (SAB). Subsequently, the IBCI converter dynamic behavior is investigated, deriving a non-linear average model that, under small-signal approximation, can be linearized around a given operating point and used for feedback controller design. A single photovoltaic module interface converter, rated for 300W output power, is considered as a case study to validate the analysis outcomes and the design procedure. Both are fully validated by measurements taken on the laboratory prototype.