Wireless Power Transmitter Positioning via Electrical Characteristic Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless power transmission systems face challenges in accurately positioning power receiving coils with varying electrical characteristics, leading to inefficiencies and potential heating of metallic objects due to leakage flux.
Innovation Solution
A wireless power transmitting device equipped with a self-oscillator circuit, detection circuit, and detection resonator that detects changes in oscillation frequency and voltage to determine the position of the power receiving coil, using a control circuit to switch between alignment and power transmission modes, and a light source or display to notify the user of proper positioning.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If wireless power transmission is performed using inductive coupling between coils, then power can be transmitted without direct contact, but positioning accuracy of power receiving coils deteriorates when electrical characteristics vary
Solution Approach 1:
The system performs preliminary detection of the power receiving coil's electrical characteristics (resistance, inductance, quality factor) before initiating power transmission. This preliminary characterization enables the control circuit to adjust transmission parameters and improve positioning accuracy specifically tailored to each coil's properties, resolving the contradiction between wireless operation and positioning precision.
Solution Approach 2:
The patent adjusts transmission parameters (frequency, power level) based on the detected electrical characteristics of the power receiving coil. By changing these parameters according to the specific coil properties, the system maintains high positioning accuracy across devices with varying electrical characteristics while preserving wireless power transmission capability.
2Ease of operation
If power transmission is performed without accurate positioning, then operation is simpler, but harmful heating of metallic objects occurs due to leakage flux
Solution Approach 1:
The system continuously monitors the electrical characteristics of the power receiving coil during operation and provides feedback to the control circuit. This feedback mechanism enables real-time adjustment of transmission parameters to maintain safe operating conditions and prevent harmful heating of metallic objects, while keeping the operation simple for the user.
Solution Approach 2:
The patent replaces mechanical positioning adjustments with electrical field-based detection and control. By using electrical characteristic measurements (resistance, inductance, quality factor) to infer positioning and adjust transmission accordingly, the system eliminates the need for complex mechanical positioning mechanisms while preventing harmful heating effects.
3Measurement precision
If detection methods are added to improve positioning accuracy, then positioning precision improves, but device complexity increases
Solution Approach 1:
The control circuit performs multiple functions: it controls power transmission, detects electrical characteristics (resistance, inductance, quality factor), and adjusts transmission parameters based on detected values. By making the control circuit multi-functional, the system achieves high positioning accuracy without adding separate complex detection hardware, thus resolving the contradiction between measurement precision and device complexity.
Solution Approach 2:
The power receiving coil itself serves as the detection sensor by measuring its own electrical characteristics (resistance, inductance, quality factor) during operation. This self-service approach eliminates the need for separate external sensors, achieving accurate positioning while minimizing additional device 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
Enables accurate positioning of power receiving coils with different electrical characteristics, preventing heating of metallic objects and ensuring efficient power transmission.
Implementation Method 1
a self-oscillator circuit which outputs an AC power for positioning, at a frequency substantially equal to a resonance frequency of a receiver resonator
Implementation Method 2
a detection resonator that outputs, to detect a position of the power receiving device, power output by the self-oscillator circuit
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A wireless power transmitting device includes a self-oscillator circuit, a detection circuit that detects at least one of an oscillation frequency of the self-oscillator circuit and an output voltage of the self-oscillator circuit, a detection resonator that outputs, to detect a position of the power receiving device, power output by the oscillation circuit, and a control circuit that detects a degree to which the power receiving device approaches the detection resonator, based on a result of a detection performed by the detection circuit.