... efficiency in a fixed-frequency mode during variations in transfer distance and orientation of the coils. In this paper, using two series transmitting coils to achieve the constant output power and transfer efficiency is used. Design/methodology/approach First, the circuit model is established...

...Suqi Liu; Jianping Tan Purpose This paper aims to find an approach that achieves constant output power and transfer efficiency in an open space, such as charging pads. Design/methodology/approach In this study, a topology of the five-coil system including two transmitting coils is presented...