Wireless Power Safety Component for NFC Coils
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Solution Overview
Problem
Magnetic resonance wireless charging systems can damage near field communication (NFC) coils due to resonance frequency interference, degrading communication quality and potentially causing damage to NFC systems.
Innovation Solution
A safety component is introduced at the power receiving unit, which includes a field effect transistor or a detuning circuit to reduce power received at the NFC coil during wireless charging, and can initiate Bluetooth Low Energy (BLE) signals to disconnect the NFC coil from its controller or adjust its resonance frequency, ensuring coexistence of wireless charging and data communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If magnetic resonance wireless charging is used to charge the device, then wireless power transmission efficiency is improved, but the resonance frequency interferes with NFC coil operations causing communication quality degradation
Solution Approach 1:
The system divides the receiving coils into two separate functional groups: a first receiving coil dedicated to wireless power reception and a second receiving coil dedicated to NFC data communication. This segmentation allows independent control and operation of each coil, enabling the power charging function to operate without interfering with the NFC communication function, thus resolving the contradiction between power transmission efficiency and communication quality.
Solution Approach 2:
The system dynamically controls the connection state of the second receiving coil (NFC coil) based on the operational state of the wireless charging. When wireless power transmission is detected, the system dynamically disconnects or detunes the NFC coil to prevent interference. This dynamic adjustment ensures that NFC communication quality is maintained during charging operations while allowing efficient power transfer when needed.
2Speed
If the NFC coil operates at its resonance frequency for data communication, then communication speed is improved, but the resonance frequency causes damage to the NFC system when exposed to wireless charging power
Solution Approach 1:
The system applies preliminary protective action by detecting the presence of wireless charging power before it can damage the NFC system. When power transmission is detected at the first receiving coil, the system proactively disconnects or detunes the second receiving coil (NFC coil) from its controller. This preliminary protective measure prevents the harmful resonance frequency interference from occurring in the first place, thereby protecting the NFC system from damage while allowing high-speed communication when safe.
3Reliability
If a safety component is added to protect the NFC coil, then NFC system reliability is improved, but device complexity increases
Solution Approach 1:
The control circuit is designed to perform multiple functions: it manages both the wireless power reception control and the NFC communication protection. By making the control circuit universal and multi-functional, the patent avoids adding separate dedicated protection circuits, thereby improving NFC system reliability without proportionally increasing device complexity. The existing control infrastructure is leveraged to provide both charging and communication management.
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 safety component effectively reduces power transfer to the NFC coil, preventing damage and allowing for simultaneous wireless charging and data communication by decoupling the NFC coil from the antenna matching component and NFC controller, or detuning the NFC coil to avoid resonance frequency interference.
Implementation Method 1
a first receiving coil to inductively couple to a wireless power transmitting unit having a transmitting coil
Implementation Method 2
a safety component to reduce an inductive coupling of the wireless power at a second receiving coil from the wireless power transmitting unit
Data Source
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AI summary
Techniques of providing increased safety for wireless systems are described herein. A wireless power receiving unit includes a first receiving coil to inductively couple to a wireless power transmitting unit having a transmitting coil. A safety component is provided to reduce wireless power received at a second receiving coil from the wireless power transmitting unit.