基于 LCC-LCC/S 可重构拓扑的无线充电系统在传感器网络中的应用

Wireless sensor networks play a crucial role in the field of power system monitoring, which can be powered through wireless power transfer (WPT) technology. During wireless power transfer process, sensors require batteries for energy storage. During the charging process, batteries initially operate under a constant current (CC) mode, then transition to a constant voltage (CV) mode. However, the prevalent QI protocol for wireless power transfer (WPT)—encompassing frequency conversion control, DC-DC auxiliary techniques, and fixed-frequency variable duty cycle modulation—fails to accommodate the CC-CV transition for battery loads in systems with a single transmitter and multiple pickups (STMP). This paper proposes a multi-pickup wireless charging system based on a reconfigurable LCC-LCC/S topology, tailored to the charging characteristics of batteries. An LCC topology is utilized on the primary side, while a reconfigurable LCC/S topology on the secondary side facilitates the CC-CV transition for battery loads. By exploiting the constant excitation current feature of the primary side's LCC topology, the system isolates the influence of changes in the number of secondary side receivers and battery load impedance on the excitation current. Additionally, a distributed transmitter coil structure is designed to work in conjunction with the LCC topology. This ensures that the received power for each pickup remains unaffected when receivers are added or removed, or when operating in different output modes (CC or CV), simultaneously achieving zero phase angle (ZPA) operation. Finally, an STMP reconfigurable LCC-LCC/S topology platform has been built, which can achieve the CC-CV transition in system with STMP. The experiments show that the overall efficiency of the system can reach 86.76% and the power factor is close to 1, which is significantly higher than the strategy in the QI protocol. Experimental results validate the feasibility of the proposed method.