Wireless Power Transmitter Foreign Object Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Wireless power transmitting devices face issues with unnecessary power consumption, malfunctioning, and shortened service life due to failure in detecting or incorrectly determining the presence of foreign objects during power transmission.
Innovation Solution
A wireless power transmitting device that includes a detector to measure voltage and current, a distance calculator to determine the distance to the receiving device, a comparator to assess power transmission efficiency, and a controller to adjust the operation mode and power magnitude based on the efficiency comparison, thereby reducing power transmission when inefficiency is detected.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If wireless power transmission is performed without foreign object detection, then power transmission efficiency is maintained, but unnecessary power consumption and malfunctioning occur due to undetected foreign objects
Solution Approach 1:
The system changes operational parameters (power transmission level) based on detected conditions. When foreign objects are detected or transmission efficiency drops below reference levels, the controller adjusts power parameters to prevent wasteful consumption while maintaining reliable operation.
Solution Approach 2:
The system implements feedback mechanisms by continuously monitoring transmission efficiency and comparing it against reference efficiency values. This feedback loop enables the controller to detect foreign objects accurately and adjust power transmission accordingly, preventing unnecessary power consumption while maintaining reliability.
2Reliability
If foreign object detection is implemented using traditional methods, then foreign object presence is detected, but incorrect determination occurs leading to malfunctioning
Solution Approach 1:
The system uses multiple parameters (voltage, current, transmission efficiency) rather than single-parameter detection. By analyzing changes in these parameters and comparing against reference values, the system achieves both high reliability in detecting foreign objects and high precision in determining their actual presence, avoiding false positives that cause malfunctioning.
Solution Approach 2:
The detection process is segmented into multiple independent measurement steps: voltage detection, current detection, efficiency calculation, and reference comparison. This segmentation allows each parameter to be measured and analyzed separately, improving overall detection accuracy and reducing false determinations.
3Reliability
If continuous monitoring of transmission efficiency is performed, then foreign objects are accurately detected, but device complexity increases
Solution Approach 1:
The controller performs multiple functions using the same hardware components: it manages power transmission, monitors voltage and current, calculates transmission efficiency, compares against reference values, and controls power adjustment. This multi-functionality reduces device complexity while maintaining high detection accuracy.
Solution Approach 2:
The system merges the detection function with the existing power control function. The same controller that manages power transmission also performs foreign object detection by monitoring transmission efficiency, eliminating the need for separate dedicated detection hardware and reducing overall system complexity.
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 solution effectively prevents unnecessary power consumption, malfunctions, and extends the service life by accurately detecting foreign objects and adjusting power transmission accordingly, ensuring efficient and stable operation.
Implementation Method 1
a transmission coil configured to be electromagnetically coupled to the receiving device
Data Source
AI summary
A wireless power transmitting device includes a wireless power generator configured to generate a wireless power based on a supplied power of a power source; a wireless power transmitter configured to transmit the wireless power to a receiving device in a wireless manner; a detector configured to detect either one or both of a voltage and a current of the wireless power transmitter; a distance calculator configured to calculate a distance from the wireless power transmitting device to the receiving device based on either one or both of the voltage and the current of the wireless power transmitter; a comparator configured to: compare a reference efficiency corresponding to the distance to a power transmission efficiency, and generate information of a transmission state based on a result of the comparison; and a controller configured to control the wireless power generator depending on an operation mode corresponding to the information of the transmission state.