Minimization of the equivalent parallel capacitance in planar magnetic integrated structures

The magnetic planar technology is nowadays an attractive solution for designing the Electromagnetic Interference (EMI) filters due to its efficiency at high frequencies and its mechanical robustness. On the other hand, the general trend of reducing the dimensions of the integrated structures one inherently leads to the increase of their structural parasitic effects. Therefore, the minimization of the parasitic capacitances and inductances represents an important issue for increasing the performances of a magnetic integrated structure. In this light, the paper proposes a method for the minimization of the equivalent parallel capacitance (EPC) of these structures based on optimal design. The paper describes the optimization algorithm developed by the authors designed to determine the optimal placement of the structure's conductor routes that minimize the structural inter-winding capacitance. In the first part of the paper the theoretical background is presented while in the second part the optimization algorithm validation and numerical examples are outlined, followed by the final conclusions.