This paper proposed a novel dipole coil using segmented windings for wireless power transfer (WPT) system with four receivers. The most attractive feature is that the couplings between transmitter and the receivers can be enhanced under the premise of lower core saturation with segmented dipole coil (SDC). Mistuning issues caused by the utilization of ferrite core are modeled and analyzed in detail. Furthermore, an optimized SDC is proposed to homogenize the magnetic field density in ferrite core. Thus, the proposed structure shares the same core saturation with dipole coil using evenly distributed windings but possesses a 30.7% more coupling strength. Eventually, an experimental prototype compensated by LCC-S topology is established. The maximum overall efficiency of four loads reaches 48% when the distance-to-diameter ratio equals to 1. The proposal of novel SDC structure can provide a significant guideline for numerous charging scenarios, such as multiple sensors or robot swarms.

Segmented Dipole Coil (SDC),wireless power transfer (WPT),magnetic field distribution (MFD),core saturation,multiple receivers