Study of a High-Efficiency WPT System with Dual Resonant Parameters Tuning Technique

Wireless charging for ships has been implemented in practical applications. However, due to variations in coupling conditions and margins of error, the system may experience detuning. While adjusting the frequency can maintain maximum efficiency on the receiver side, it also increases switching losses. To address this, this paper proposes a wide-frequency WPT system based on LCC-S compensation topology. The system incorporates variable inductor and variable capacitor techniques along with a dual-variable control method to ensure system stability during adjustments. Additionally, a sensorless foreign metal detecting technique is introduced, preventing safety from metal intrusion. A 300W WPT system prototype was developed to assess feasibility, and the results show that under horizontal and vertical misalignment variations of ±50% and +175<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">%</sup>, respectively, zero-voltage-switching (ZVS) was achieved in the resonant input, with system efficiency consistently above 86%, upon considering ESR.