Design and optimization of small inductors on extra-thin PCB for flexible cooking surfaces

The following paper describes the design and optimization method for a small inductor in printed circuit board, which is later used in the implementation of a flexible cooking surface prototype. The method combines an analytical model of an induction system formed by rectangular cross-sectional conductors and Finite Element Analysis (FEA) simulations, providing an important decrease of the computational costs. This is followed by the corresponding calculations in order to minimize conduction and proximity losses in the winding while the copper volume and the power dissipation in the inductor are optimized. A parametric analysis is carried out to define the induction system that leads to the optimal efficiency, which, moreover, proves extra-thin PCBs as the most suitable solution. A laboratory prototype was implemented using a PCB litz structure and tested under real working conditions. The empirical characterization produced good results, being consistent with the simulations and showing a proper thermal behavior.