Inductive Power Transfer System With High Misalignment Based on Detuned Series-Series Compensation Topology

To mitigate the output power fluctuation caused by physical misalignment in the inductive power transfer (IPT) system, a novel discrete frequency detuned method is proposed. Based on series-series (S-S) compensation topology, a general mathematical model considering the imaginary part and equivalent series resistance (ESR) has been derived. Subsequently, the output power, primary current, and transmission efficiency against mutual inductance under various frequencies are numerically analyzed. A modified transmission model with higher calculation accuracy, considering the inductance change, is proposed. Systematic design procedures and operation principles of detuned S-S IPT systems are presented, which showcase highly flexible design freedom with any output fluctuation requirements. Finally, an IPT system with adjustable working frequencies is built to verify the theoretical analysis. The experimental results show appealing advantages over other methods, with the minimized power fluctuation of 1.63% when the coupling coefficient changes from 0.53 to 0.22. The IPT system realizes 300 W output with a maximum transmission efficiency of 94.9%.