Development of the optimization framework for low-power wireless power transfer systems

Considering the high level of complexity inherent in wireless power transfer (WPT) systems, the foremost concern in the field is the development of an efficient and systematic design framework that can improve an objective function (e.g., transfer efficiency and system mass) while satisfying multiple constraint functions such as the electromagnetic fields, air-gap, and power capacity transferred. In this paper, an optimization framework for real-world WPT systems is developed through connecting commercial electromagnetic field analysis software and an optimization module using in-house codes. The developed design framework is validated with both unconstrained and constrained optimization cases and then applied to minimize the thickness of the secondary module in a wireless portable device charger. Using the proposed optimization framework, the thickness is successfully and efficiently reduced while the induced voltage and electric and magnetic fields are satisfied.