Abstract:
To realize the efficient and reliable inductive power transfer (IPT) system, primary and secondary pads should be well aligned. However, it is inevitable with pad misalignment in many practical IPT applications. To solve this issue, this paper proposed a kind of universal hybrid IPT couplers with high tolerance to pad misalignment, which combined a conventional bipolar (BP) coupler and a high-order compensation network of parallel-series-series (PS-S) or series-series-parallel (PS-S). Moreover, the proposed hybrid IPT couplers were applicable to all IPT topologies. Besides, the introduction of high-order network can simplify the design of BP coupler, where one set of two overlapped coils on the same side can be effectively decoupled. Although the other set of two overlapped coils still couple together, the coupling inductance can be readily designed to guarantee cross-coupling inductances as small as possible, which can save the iteration design of BP coupler. Finally, a 3kW IPT prototype using the proposed hybrid coupler and S-S compensation was built to illustrate the design of the IPT system with constant current (CC) output under both load and coupling variations. Experimental results verified the theoretical analysis well.