Wireless Power Transfer Using Reflector-Mediated Near-Field Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless charging technologies face challenges in efficiently transferring power over reasonable distances and accommodating flexible placement and orientation of antennas, with existing methods suffering from distance limitations and requiring precise alignment, which restricts their practicality for charging multiple devices simultaneously.
Innovation Solution
The use of large loop antennas with resonant frequencies adjusted for near-field coupling, combined with repeater antennas to enhance power transfer efficiency and allow for flexible placement and orientation, enabling effective energy transfer over larger areas and distances.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If plane wave radiation coupling is used between transmit and receive antennas, then wireless power transmission can be achieved, but power coupling efficiency drops quickly with distance
Solution Approach 1:
The patent introduces a reflector as an intermediary element between the transmit and receive antennas. The reflector redirects and focuses the radiated electromagnetic energy back toward the receive antenna, effectively mediating the energy transfer process. This allows plane wave radiation to be used for wireless power transmission while significantly reducing power loss over distance by recapturing and redirecting otherwise lost radiated energy.
2Quantity of substance
If inductive coupling between transmit and receive antennas is used, then multiple devices can be charged simultaneously, but the spacing between antennas must be very close
Solution Approach 1:
The patent transitions from near-field inductive coupling to far-field plane wave radiation, effectively changing the dimensional regime of operation. By using a reflector to manage the far-field radiation patterns, the system achieves wireless power transmission over extended distances while maintaining the capability to charge multiple devices simultaneously within the expanded coverage area.
3Length of moving object
If plane wave radiation is used for wireless power transmission, then wireless charging over reasonable distances is possible, but unintentional radiation can interfere with other systems
Solution Approach 1:
The patent employs a reflector to create a localized concentration of electromagnetic energy between the transmit antenna and the target area. By shaping and directing the radiation pattern, the system achieves effective power transmission over reasonable distances while confining the intense radiation to specific regions, thereby reducing unintentional interference with other systems in surrounding areas.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly improves power transfer efficiency, allowing for reliable charging of multiple devices at varying distances and orientations, enhancing the practicality and convenience of wireless charging systems.
Implementation Method 1
The antennas are tuned to have a common resonant frequency and are oriented such that a measure of near-field coupling exists between the transmit antenna and the receive antenna
Implementation Method 2
The combination of the transmit antenna and the repeater antennas in the power transfer system may be optimized such that coupling of power to very small receive antennas is enhanced
Data Source
Figure 1~2
Figure 3~4
Figure 5A~7
AI summary
Exemplary embodiments are directed to wireless power transfer. A transmitting device or a receiving device for use in a wireless transfer system may be equipment or a household appliance. The transmitting device includes a transmit antenna to wirelessly transfer power to a receive antenna by generating a near field radiation within a coupling-mode region. An amplifier applies an RF signal to the transmit antenna. A presence detector detects a presence of a receiver device within the coupling-mode region. A controller adjusts a power output of the amplifier responsive to the presence of a receiver device. The presence detector may also detect a human presence. The power output may be adjusted at or below the regulatory level when the presence signal indicates human presence and above a regulatory level when the presence signal indicates human absence.