Inductive Power Transmission for Wearable Textile Heater using Series-None Topology

In this paper, an inductive-power-transmission (IPT) system for a wearable textile heater is proposed to comfortably provide heating to a user's body. The conductive thread, which has high electrical resistance, was sewn into a receiver (Rx) coil on clothing to generate high temperature with a low current. The proposed wearable heaters are completely washable thanks to their nonmetallic materials, other than conductive threads in the clothing. We introduced series-none (SN) topology to eliminate a resonant capacitor in the wearable textile heater. A single resonant capacitor in a transmitter (Tx) in SN mode was implemented to resonate both Tx and Rx, resulting in increased power delivered to the load (PDL) while maintaining high-power transfer efficiency (PTE), comparable with conventional series-series (SS) topology. When the supply voltage of the power amplifier was 7 V, while the PTE of the SS and SN modes was 85.2% and 75.8%, respectively, the PDL of the SS and SN modes was 2.74 and 4.6 W, respectively.