A Study on the Optimal Magnetic Beam Forming of Coil Arrays for Long Distance Wireless Power Transmission

Area of Science:

• Electrical Engineering
• Wireless Power Transfer
• Electromagnetics

Background:

• Multiple-input multiple-output wireless power transfer (MIMO-WPT) uses multiple transmitter coils to enhance power transfer efficiency (PTE).
• Conventional MIMO-WPT systems use phase-calculation based on phased-array beam steering, which can degrade signal reception with more or distant transmitter coils.
• Increasing transmitter coil numbers and distances to improve PTE can paradoxically reduce the received signal at the receiver coil.

Purpose of the Study:

• To present a novel phase-calculation method for MIMO-WPT systems to enhance PTE.
• To improve the performance of MIMO-WPT by addressing signal degradation issues with increased coil complexity.
• To enable high-efficiency wireless charging for electronic devices within a defined space.

Main Methods:

• A new phase-calculation method is proposed for MIMO-WPT systems.
• The method incorporates coil coupling effects into the calculation of coil control data.
• Phase and amplitude adjustments are applied based on calculated coil control data.

Main Results:

• The proposed phase-calculation method significantly enhances PTE in MIMO-WPT systems.
• Experimental results show transmission coefficient improvements ranging from 2 dB to 10 dB compared to conventional methods.
• The improved method overcomes signal deterioration issues associated with increased transmitter coil configurations.

Conclusions:

• The developed phase-control MIMO-WPT method effectively enhances wireless power transfer efficiency.
• This technology facilitates high-efficiency wireless charging for electronic devices in various spatial locations.
• The proposed method offers a viable solution for improving the performance and practicality of MIMO-WPT systems.