Wireless Power Feeder Phase Detection Circuit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless power feeding technologies using magnetic field resonance struggle to maintain drive frequency synchronization with resonance frequency, leading to reduced power transmission efficiency and stability due to external distortions and resonance frequency deviations.
Innovation Solution
A wireless power feeder system incorporating a power transmission control circuit, phase detection circuit, and reset circuit that adjusts the drive frequency based on phase difference between voltage and current waveforms, using a feeding coil, exciting coil, and receiving coil to maintain resonance frequency tracking and stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If magnetic field resonance type wireless power feeding is used for intermediate range power transmission, then power transmission efficiency is improved, but drive frequency synchronization becomes difficult to maintain due to external distortions and resonance frequency deviations
Solution Approach 1:
The patent implements a feedback mechanism where the phase detection circuit continuously monitors the phase difference between voltage and current waveforms, and the power transmission control circuit adjusts the drive frequency based on this feedback to maintain synchronization with the resonance frequency, thereby resolving the contradiction between maintaining high power transmission efficiency and ensuring frequency synchronization stability under external disturbances
Solution Approach 2:
The patent dynamically changes the drive frequency parameter in response to detected phase differences, allowing the system to adapt to resonance frequency deviations caused by external distortions while maintaining optimal power transmission efficiency through continuous parameter adjustment
2Reliability
If phase detection and frequency adjustment circuits are added to maintain resonance tracking, then frequency synchronization stability is improved, but device complexity increases
Solution Approach 1:
The power transmission control circuit performs multiple functions including phase difference detection, frequency adjustment, and power transmission control, reducing the need for separate dedicated circuits and thereby minimizing the increase in device complexity while maintaining frequency synchronization stability
3Loss of energy
If drive frequency is continuously adjusted to track resonance frequency, then power transmission efficiency is maintained, but system stability may be reduced due to frequent adjustments
Solution Approach 1:
The patent implements periodic phase detection and frequency adjustment rather than continuous adjustment, allowing the system to maintain power transmission efficiency through regular synchronization checks while ensuring stability by providing predictable, periodic control actions that avoid excessive or erratic frequency changes
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 system enhances power transmission efficiency and stability by automatically adjusting the drive frequency to match the resonance frequency, even in the presence of external disturbances, ensuring reliable and efficient power transfer.
Implementation Method 1
When AC power is fed to the exciting coil, current also flows in the feeding coil according to the principle of electromagnetic induction
Implementation Method 2
When the feeding coil generates a magnetic field to cause the feeding coil and receiving coil to magnetically resonate, large current flows in the receiving coil
Implementation Method 3
current also flows in the loading coil according to the principle of electromagnetic induction, and power is taken out from a load R connected in series to the loading coil
Data Source
AI summary
Power is transmitted from a feeding coil L2 to a receiving coil L3 by magnetic resonance. A VCO 202 alternately turns ON/OFF switching transistors Q1 and Q2 to feed AC current to the feeding coil L2, whereby the AC power is fed from the feeding coil L2 to the receiving coil L3. An AC magnetic field generated by AC current IS flowing in the feeding coil L2 causes inductive current ISS to flow in a detection coil LSS. A phase detection circuit 150 compares the phase of AC voltage generated by the VCO 202 and phase of the inductive current ISS to detect the phase difference between voltage and current phases and generates phase difference indicating voltage indicating the magnitude of the phase difference. The reset circuit 102 forcibly reduces the phase difference indicating voltage when the phase difference indicating voltage exceeds a predetermined threshold.