A hybrid topology wireless charging system for AGVs with strong anti-offset performance

When AGVs are parked for wireless charging, misalignment and offset between the transmitting and receiving coils are prone to occur, which affects the charging power and efficiency. To address this issue, this paper proposes a novel flat cross-shaped self-decoupling electromagnetic coupler for AGVs that require strong anti-offset performance in a hybrid topology wireless charging system. Firstly, a hybrid topology combining CLC-S compensation topology and S-CLC compensation topology is proposed. The principle of achieving anti-offset, the load-independent output characteristics, and the safety of the system in a weak coupling state are analyzed. Secondly, a new magnetic coupling mechanism is proposed, which can eliminate all cross-couplings generated in the proposed hybrid topology. Finally, a 200 W output power experimental platform is built. The maximum DC-DC efficiency of the system is 89.13%. The maximum X-axis offset of the system reaches 53.46% of the coil size, the maximum Y-axis offset is 9.43% of the coil size, and the maximum Z-axis offset reaches −37.78% to +13.33% of the rated transmission distance. The load-independent constant voltage output characteristics of the proposed system and its safety in a weak coupling state are also verified.