Pre-optimization of linear and nonlinear inductors using area-product formulation

A novel technique to pre-optimize linear and nonlinear inductors in switched mode power supplies is presented using the area-product formulation. The method delivers approximate size and design information for linear air-gapped ferrite-core inductors and nonlinear distributed-gapped powder core inductors as input of the final core selection and winding design. The model accuracy allows a comparative study of linear, air-gapped and nonlinear, distributed-gapped inductor designs at a very early development stage, e.g. concept phase, without building prototypes. The paper describes the mathematical background of the method and proves the practical benefits along with example designs.