Three‐dimensional rotatable omnidirectional MCR WPT systems

Abstract

Recently, Wi-Fi wireless power transfer (WPT) has attracted increasing attention. In this study, a rotatable threedimensional (3D) transmitter (Tx) is first designed which only needs to be powered by a single source without current amplitude or phase control. Mutual inductance formulas of the Tx and a receiver (Rx) during the Tx's 3D rotation are derived based on Biot-Savart law and rotating matrix, and the maximum coupling areas are obtained. A method of achieving equal coupling of Rxs with the Tx which simultaneously charges two Rxs is proposed. A real rotatable 3D Tx and an omnidirectional magnetically coupled resonant (MCR) WPT prototype are fabricated, and the theoretical analysis is verified by simulation and experiment. Experiment displays that the maximum or desired coupling of single or two Rxs in 3D space can be obtained by calculated rotation combinations. The maximum power transfer efficiency (PTE) of the system can reach 90.2% with the transmission distance of 1.5 times the radius of Tx. Finally, the PTE can be maintained at 73% with the transmission distance varying from 18 to 27 cm by a novel method. The proposed 3D technique could be applied to many fields including Wi-Fi WPT home devices, remote sensing and some mechanical systems.

Modelling and Control Design of a Non-Collaborative UAV Wireless Charging System

“…A cubic magnetic dipole coils arrangement was also proposed in [ 8 ] for omnidirectional and multi-load power transmission. Another study showed a 3D wireless charging cylinder with two orthogonal coils that can generate a spinning magnetic field to charge numerous loads [ 9 ]. The system of multiple bowl-shaped transmitting coils reported by the authors in [ 10 ] can create a uniform magnetic field inside the charging region to compensate for the misalignment issue.…”

Design of novel coil structure for wireless power transfer system supporting multi-load and 2-D free-positioning

“…The omnidirectional WPT system, which can generate a controllable rotational magnetic field pointing to the load, has attracted much attention in recent years [8,9]. An omnidirectional WPT system comprising a transmitter with three orthogonal coils has addressed [10][11][12][13][14][15][16][17][18].…”

“…Fig 13. Schematic diagram and simulation results when load1 and load2 with same radius moving circumferential direction.…”