Parameter Design and Optimization of Long-distance Multi-relay Wireless Power Transfer Systems at High Frequencies

This paper presents a design and optimization methodology for a high-frequency long-distance multi-relay wireless power transmission system based on equidistant arrangement of relay coils. To obtain an accurate equivalent circuit model under high-frequency conditions, the study constructs frequency-dependent parasitic resistance fitting functions for both coils and capacitors, establishing a theoretical correlation model between transmission power and frequency. By formulating the objective of maximizing system output power, a systematic sweep analysis is conducted over the frequency range of 0.9-2.0 MHz to determine the optimal operating frequency. Furthermore, the research investigates the impact of relay coil parameter deviations and mutual inductance variations on transmitter coil current characteristics, offering improved design insights for system optimization. Simulation results substantiate the validity of the theoretical analysis, demonstrating the proposed framework's effectiveness in achieving desired performance metrics.