PCB Layout Optimization of High-Frequency Inverter for Magnetic Coupled Resonance Wireless Power Transfer System

Magnetic coupled resonance wireless power transfer system has the advantages of long transfer distance and high efficiency. However, it needs a high-frequency AC power, and the influence of the circuit parasitic elements at high frequency cannot be ignored, which brings challenges to the research and the design of the high-frequency power for the wireless power transfer system. In this paper, the effect of the parasitic elements in the full-bridge inverter and the reasons of high-frequency ringing generated are analyzed in detail. The influences of device packaging and the printed circuit board (PCB) layout on circuit parasitic elements are studied. An optimized inverter PCB layout design that aims to reduce the parasitic elements and to provide a stable and high-quality AC power for the wireless power transfer system is presented. Finally, the performance of the conventional PCB layout design and the proposed optimized PCB layout design are compared through experiments. The experiment results show that the proposed design not only reduces the parasitic inductance in the circuit, but also reduces the electromagnetic interference noises and improves the stability of the inverter at 900kHz switching frequency.