A Domino-Type Load-Independent Inductive Power Transfer System with Hybrid Constant-Current and Constant-Voltage Outputs

This paper proposes a load-independent domino-type inductive power transfer (IPT) system for multiple loads with a simple structure and a long-distance transfer capability. Hybrid constant-current (CC) and constant-voltage (CV) outputs are achieved. Compared to existing designs, there are two innovative contributions. First, the proposed domino-type IPT topology uses fewer coils and ferrite materials to achieve load-independent outputs, which significantly simplifies system structure and improves power density. Second, a unipolar domino coupler configuration is proposed, enabling the long-distance power transfer capability as well as suppressing the cross-coupling effect. With the proposed IPT topology, the magnetic coupler design is provided and validated by 3-D finite element analysis (FEA). Impacts of parasitic resistances are analyzed, revealing the practical output attenuation versus load variation and the efficiency relationship with load resistance, coupling coefficient k, quality factor Q, and load number N. With an efficiency-based parameter design method provided, a 330-W single-input-four-output prototype is implemented over a total transfer distance of 0.9m with a 300mmx300mm domino coupler. Experimental results validate the load-independent CC and CV outputs, and the efficiency can reach 83.78% at N=4 and k=0.055.