A Wireless Power Transfer System Based on Hybrid Self-switching of Coupled Inductors

This paper proposes a wireless power transfer system based on hybrid self-switching of coupled inductor that not only realizes constant current (CC)/constant voltage (CV) output but also effectively copes with a variety of abnormal working conditions in the charging process by switching on the secondary side. First, the LCC-LCC/S self-switching composite topology is presented, and the CC/CV switching is achieved by utilizing a coupled inductor with a center tap based on the LCC compensation topology. The working principle of the CC/CV topology and the parameter calculation flow are analyzed in detail. Subsequently, the impedance, output characteristics, and switching characteristics of the constant current/constant voltage topology are simulated and analyzed. Additionally, the topology's stability under abnormal working conditions, such as the missing adjacency, load short-circuit, and load open-circuit, is analyzed. Finally, an experimental platform is constructed with the objective of verifying the feasibility and effectiveness of the proposed scheme. The experimental results demonstrate that the proposed charging system exhibits excellent constant current and constant voltage output characteristics without the need for additional inductor capacitance. The proposed system has a maximum output efficiency of 89.6%, a maximum current of 5.3A, and a maximum voltage of 23V, which fully meets the requirements of constant current and constant voltage wireless charging.