A Novel Methodology for Identifying and Quantifying Losses in Wireless Power Transfer Systems

This study proposes a novel methodology for quantifying losses in wireless power transfer systems (WPTs). By employing a circuit model derived from just three finite element simulations (FEM), it enables the separation of loss contributions from the magnetic and mechanical components across all operating conditions. This streamlined approach proves highly effective, providing a thorough analysis with minimal computational effort, thereby facilitating the optimization of the part that represents the bottleneck for this type of application. A mobile phone test case was used because the charging power is limited by the rise in temperature on the receiver. Identifying the elements responsible for significant dissipation within the receiver system via conventional measurements proves practically infeasible due to the low power levels involved. Consequently, a finite element simulation is necessary for each operating condition. After presenting and demonstrating the methodology, the study illustrates the figure of merit (FOM), which provides insight into the quality of the receiver coil, identified as the most critical element of the charging system. A case study will offer a practical example of the methodology, verified with experimental measurements.