Wireless Power Transfer Foreign Object Detection via Waveform Attenuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless power transmission systems face increased costs and decreased transmission efficiency due to the need for additional circuits and time to transmit foreign object detection signals, as seen in current foreign object detection methods.
Innovation Solution
A power transmitting apparatus is designed with a measuring unit to assess waveform attenuation rates, a setting unit to establish thresholds, and a determining unit to detect foreign objects based on these measurements, allowing for foreign object detection without the need for a dedicated detection signal, thereby reducing costs and improving efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a dedicated foreign object detection signal transmission circuit is added, then foreign object detection capability is improved, but device complexity and cost increase
Solution Approach 1:
The power transmitting apparatus uses its existing power transmission circuit to perform dual functions: transmitting power to the power receiving apparatus and detecting foreign objects. By measuring waveform attenuation of the power transmission signal itself, the system eliminates the need for separate detection circuits, thereby maintaining detection capability while reducing device complexity and cost.
Solution Approach 2:
The patent combines the power transmission function and foreign object detection function into a single integrated process. The same transmission circuit and signal path are used for both purposes, merging what would traditionally be separate systems into one unified approach that reduces overall system complexity.
2Reliability
If a dedicated foreign object detection signal is transmitted, then foreign object detection accuracy is improved, but transmission efficiency decreases due to additional time requirements
Solution Approach 1:
The system performs foreign object detection continuously during the power transmission process without interrupting or pausing the power delivery. The waveform attenuation measurement is conducted on the ongoing power transmission signal, allowing detection to occur continuously alongside power transmission, thereby maintaining both detection accuracy and transmission efficiency.
Solution Approach 2:
The detection process is merged with the power transmission process, occurring simultaneously rather than sequentially. This eliminates the need for separate detection time slots and maintains continuous power transmission, thereby preserving transmission efficiency while achieving reliable detection.
3Device complexity
If waveform attenuation rate measurement is implemented, then foreign object detection is achieved without additional circuits, but measurement precision requirements increase
Solution Approach 1:
The system implements a feedback mechanism where the waveform attenuation rate is measured and compared against predetermined thresholds to determine the presence of foreign objects. This feedback-based approach with threshold comparison simplifies the measurement requirements by converting precise continuous measurement into discrete threshold-based detection, reducing the actual measurement precision burden while maintaining detection reliability.
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 enables effective foreign object detection within the wireless power transmission system, enhancing efficiency and reducing costs by eliminating the requirement for additional detection signal transmission circuits.
Implementation Method 1
a power transmitting unit (103) configured to wirelessly transmit power to a power receiving apparatus (401) via a power transmitting antenna (105)
Implementation Method 2
a measuring unit (303) configured to measure a waveform attenuation rate of a transmission power waveform
Data Source
AI summary
A power transmitting apparatus measures a waveform attenuation rate of a transmission power waveform, at a transmission antenna, in a state in which the power transmission by the power transmitting is restricted, sets a threshold used for detecting a foreign object between the power transmitting apparatus and the power receiving apparatus on the basis of the measured waveform attenuation rate, and determines whether or not the foreign object is present on the basis of the waveform attenuation rate measure after the threshold is set and the threshold.