A Novel Tubular Coupler Application in Wireless Power Transfer

Because of the skin effect, the high-frequency current of wireless power transfer (WPT) is concentrated on the surface of coils. To realize the lightweight of the WPT device, the tubular coupler with skin effect is a method to optimize the coil weight. In addition to the common copper tube as the coupler, the aluminum tube coated with a thin layer of copper is proposed as the coupler coil in this letter. This novel coupler not only reduces the weight but also ensures the transmission efficiency. The experimental results show that the weight of Coppersurfaced Aluminum Tubes (CAT) is reduced by 36g than copper tubes. The power gain is slightly reduced by 2.1% at 13.56 MHz. The gain weight ratio (GWR) is increased by 1.7 times. This new structure tubular coupler is more suitable for applications which need lightweight requirements urgently.