A shared physical communications channel is designed and implemented in this paper for inductive (contactless) power transfer (IPT) applications, wherein data are transferred without interfering power transfer, and, thus, maintained the efficiency of the IPT system. The channel is made of coupling coils, which are used to control the system and to transfer data bidirectionally at the rate of 19.2 Kb/s. To make the system work in two relatively independent modes, the wave trappers (passive bandpass and band-reject filters) are added into the system, and an integrated mathematical model is established based on separate models of data and power transfer. The proposed method was tested on a laboratory scale prototype, and was proved to be reliable for the parallel transmission of power and data. Therefore, the proposed method can be used to improve performance of the IPT system by precise control due to communication between the primary side and the pickup side.

Keywords:Impedance, Communication channels, Capacitors, Interference, Attenuation, Coils, Band-pass filters