Coupling Characteristics and Optimization of the Resonators Applied to the Power Supply System of Tail-free Household Appliances

Abstract

As household appliances become more and more intelligent, increasingly strict demands are put forward for their power supply. Existing draw-out power supply mode of household appliances has many shortcomings including low waterproof grade, touch spark, and wire constraint. Considering this, a tail-free power supply system based on magneticallycoupled resonant wireless power transfer (MCRWPT) technology is investigated. Aiming at the coupling problems, such as frequency splitting, of the resonator during the design of the system, the analytic calculation is adopted to obtain the advisable domain values of mutual inductance that can evade frequency splitting. On this basis, the authors also carry out theoretical calculation on the combination modes of disc spiral coils and spatial spiral coils so as to attain the accurate mutual inductance between the resonators. In addition, a calculation method more accurate than the traditional Neumann formula is also proposed. The theoretical analysis is finally validated by conducting simulation and experiments and comparing the obtained results.