Analysis of the Eigenvalue Distortion in a Double-Sided LCC-Compensated Stationary Automotive WPT System during Coil Alignment

Due to lateral coil misalignment in automotive wireless power transfer (WPT) systems, its eigen-frequencies are inherently distorted. This paper contributes to the fundamental analysis of resonant tank detuning in doubled-sided LCC-compensated stationary automotive WPT systems during the coil alignment prior to charging. Therefore, the system’s input impedance is analyzed in the complex frequency domain in terms of its poles and zeros. A reference design from the latest SAE J2954 standard is simulated in a Finite-Element-Analysis to account for the positioning dependency of the coupled coils system. For a double-sided LCC-compensated WPT system, the impedance behavior at the input and output terminals of the circuit is then characterized by means of a First Harmonic Approximation (FHA). Through this, system characteristics useful for further investigations concerning VA positioning feedback are revealed.