Analytical Investigation of Frequency Splitting Phenomena in Detuned Wireless Power Transfer Systems

This paper presents an analytical investigation of frequency splitting in detuned wireless power transfer (WPT) systems. While frequency splitting has been extensively studied, prior research has insufficiently addressed the effects of resonant circuit detuning, which commonly occurs in practical applications due to capacitance drift, coil misalignment, or intentional detuning for zero-voltage switching (ZVS). To fill up this gap, this study systematically examines the impact of detuning on frequency splitting. The analysis begins by characterizing the system's power transfer capability and input impedance behavior under detuned conditions. Subsequently, the effects of both primary and secondary detuning on frequency splitting are explored. Additionally, the critical boundaries for frequency splitting under dual-side detuning are established. Experimental results validate the proposed methodology, confirming its effectiveness in enhancing the understanding of frequency splitting in detuned WPT systems. © 2025 IEEE.