Dual-Side Adaptive Tuning Cooperative Control for Tracking Zero Phase Angle and Maximum Output Voltage in Dynamic LCC-S WPT System

Practical dynamic wireless power transfer (WPT) charging scenarios present challenges such as variations in self-inductances due to coil misalignment and drift in capacitor parameters, which can disrupt the resonance state and reduce power output and efficiency. In order to solve these issues, this article incorporates switch-controlled capacitors (SCC) into the LCC-S topology to perform adaptive tracking for zero-phase-angle (ZPA) and maximum output voltage across a large-scale coupling space and wide-range load variations. The proposed tuning method eliminates the need for additional phase-assisted detection circuits, wireless communication, complex mathematical calculations, and parameter identification. First, a unified impedance detuning model considering severe detuning is developed and reveals the detrimental effects of detuning on transmission characteristics. Then, a simple phase detection method combined with a PI control is employed on the transmitter, and an adaptive-step perturb and observe (AS-P&O) algorithm on the receiver for cooperative tuning and decoupling control. Finally, an experimental prototype is constructed to verify the effectiveness of the method when the output power ranges from 200 to 600 W and the coupling coefficient varies from 0.69 to 0.32. Compared with the detuning, the tuning system restored the output voltage from 56 to 114 V at $R_{\text {L}} = 20~\Omega $ and increased the efficiency by 10.1% at most, and the maximum efficiency is realized at 92.19%.