Wireless Power Receiving Coil Foreign Object Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless power transfer systems face safety concerns due to the potential for heat generation and damage when foreign objects, such as metallic pieces or IC tags, are present between the power feed and receiving devices, leading to a need for effective detection and control mechanisms to ensure safe operation.
Innovation Solution
A power receiving device and electronic apparatus that include a power receiving section and a communication section, where the communication section transmits coil information to the power feed device indicating the presence of a coil near the power receiving coil, allowing for safe operation by preventing power transfer in the presence of foreign objects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If wireless power transfer is performed using magnetic coupling method, then power can be transferred wirelessly to electronic devices, but heat generation and safety issues occur when foreign objects are present between power feed and receiving devices
Solution Approach 1:
The system performs foreign object detection before initiating power transfer by analyzing coil information from the receiving device. This preliminary detection identifies the presence of foreign objects (such as metallic pieces or IC tags) near the receiving coil, allowing the system to prevent power transfer that would cause harmful heat generation while still enabling safe wireless charging when no foreign objects are present
2Reliability
If foreign object detection is implemented to prevent heat generation, then safety is improved, but system complexity increases due to additional detection mechanisms
Solution Approach 1:
The receiving device actively transmits coil information (such as coil position, size, and surrounding environment data) back to the power feed device. This feedback mechanism enables the power feed device to determine whether foreign objects are present near the receiving coil and control power transfer accordingly, achieving safety through information exchange rather than complex additional detection hardware
Solution Approach 2:
The patent uses communication signals as an intermediary to convey coil information from the receiving device to the power feed device. This intermediary approach allows the system to detect foreign objects by analyzing transmitted coil data without requiring direct physical sensors or complex detection mechanisms at the power feed device, thus maintaining system simplicity while improving safety
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
The solution enhances safety by enabling the detection and prevention of power transfer to foreign objects, reducing the risk of heat generation and damage, thereby improving the overall safety of the power feed system.
Implementation Method 1
The electromagnetic induction method and the magnetic resonance coupling method are often collectively referred to as a magnetic coupling method
Implementation Method 2
a magnetic resonance coupling method using a resonance phenomenon
Data Source
AI summary
A power receiving device according to the present disclosure includes a power receiving section that receives power from a power feed device with use of a power receiving coil; and a communication section that transmits coil information to the power feed device, the coil information indicating whether or not a coil is provided near the power receiving coil.