Transfer efficiency analysis of magnetic resonance wireless power transfer with intermediate resonant coil

Generally, for the magnetic resonance coupling wireless power transfer (WPT) system, the transfer efficiency and the transmission distance are contradictory. In order to simultaneously achieve the high transfer efficiency and the far transmission distance, some researchers have successfully proposed to use intermediate coils system to improve efficiency of WPT. In this paper, the expression for the efficiency of intermediate WPT system is obtained by applying coupled-mode theory. System efficiency is improved by optimizing key parameters of system. The intermediate WPT system via magnetic resonance coupling is designed. Simulation and experimental results validate the proposed optimization method. (C) 2014 AIP Publishing LLC.