Modeling and investigation of magnetically coupled resonant wireless power transfer system with varying spatial scales

Previous work reveals that the magnetically coupled resonant (MCR) wireless power transfer (WPT) technology is efficient and practical for mid-range wireless energy transmission, able to handle nontrivial amount of power. This paper presented an equivalent analytical model for MCR WPT system to incorporate spatial misalignments between the transmitting coils and receiving coils. The mutual inductance formulas were derived when receiving coils are laterally, angularly or generally misaligned from transmitting coils. The relationship among the output power, transmission efficiency and the mutual inductance, load resistance were analyzed in detail. Experiments had also been carried out to facilitate quantitative comparison and validate the theoretical analysis.