While many companies have launched various wireless chargers in mobile industries, conventional wireless power transfer (WPT) technologies are available only for a very short distance due to large attenuation of the magnetic fields. A magnetic beamforming WPT system achieves an enhanced power transfer efficiency (PTE) with a longer wireless charging distance by focusing the magnetic fields to the receiver. However, con-ventional magnetic beamforming scheme needs complex calculation for optimal input voltage due to the magnetic couplings between multiple transmitters. Additionally, these couplings diminish the PTE of the WPT system. This paper presents the maximum performance of the WPT system with multiple transmitters to the single receiver by transceiver optimization. In the transmitter side, a magnetic beamforming with a non-coupling coil pattern is introduced. Our proposed optimization in the transmitter side can achieve the enhanced PTE by controlling the only magnitude of the voltage source compared to the conventional magnetic beamforming. In the receiver side, a load optimization is introduced. The method for finding the optimal load impedance value is derived. After optimization in both sides, the WPT system can achieve a maximum performance under any circumstances. The improvement is verified via circuit simulation. ⓒ 2017 DGIST
Table Of Contents
Ⅰ. Introduction 1--
II. Basic Analysis of WPT System 6--
2.1 Circuit Analysis 6--
2.1.1 Single Transmitter to Single Receiver 6--
2.1.2 Multiple Transmitters to Single Receiver 9--
2.2 Introduction of Magnetic Beamforming Scheme 12--
2.2.1 Principle of Magnetic Beamforming Scheme 12--
2.2.2 Verification of Improved Performance through Circuit Simulation 16--
III. Optimization in the Transmitter 20--
3.1 Introduction of a Non-coupling Coil Pattern 20--
3.2 Derivation and Verification of Optimization in the Transmitter 22--
IV. Optimization in the Receiver 26--
4.1 Introduction of Load Impedance Optimization 26--
4.2 Derivation and Verification of Optimization in the Receiver 27--