Design considerations for high power density/efficient PCB embedded inductor

This paper presents the design and implementation of high power density and highly efficient air-core embedded inductor onto Printed Circuit Board (PCB) for 280W-5A/240nH, 280W-12A/150nH and 280W-18A/50nH. The toroidal structure due to its better performance on interfacing electromagnetic fields (EMI), is investigated. In addition, thermal restrictions are considered at high current capacity by reducing the inductor size. This will bring the advantage of lower resistivity and consequently the conduction loss. Other challenges such as temperature rise optimization of high current (18A) on the PCB is also investigated. First, parameter calculation for design consideration of an embedded inductor are presented, then JMAG simulations are used to observe precisely the temperature rise profile distribution in different sections of the inductor. An optimized design to achieve high efficient inductor and simultaneously high power density is proposed and several experiments and accurate designs are shown. The primary results show an acceptable temperature rise for high current (18A) inductor without the heat sink.