Design coupled inductors for interleaved converters using a three-leg core

We describe a method for determining the split winding distribution for coupled inductors in interleaved converters. Our method greatly reduces the footprint and copper losses of the magnetic component. We discuss the analysis and design method for the coupled inductors in detail. We use a geometrical method to solve problems such as uneven fluxes of different legs and magnetic core selection criteria and optimizations. We use a flowchart to design the coupled inductor, and constructed a 400-W prototype by following it. We present some comparisons between our method and those presented in the literature. Simulation and experimental results demonstrate that our method is effective and straightforward.