Parallel Coil Module With Capacitance Balancing for Loss Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless charging technologies face inefficiencies due to impedance differences between parallel coils, leading to uneven current distribution and increased loss, especially at high frequencies, which cannot be effectively mitigated by thicker winding wires or resonant capacitors alone.
Innovation Solution
A coil module with at least two parallel branches, each comprising a coil and a first capacitor connected in series, where the capacitances of the capacitors are set to reduce or eliminate equivalent impedance differences between the branches, ensuring uniform current distribution and reducing loss.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If thicker winding wire is used to reduce coil loss, then current carrying capacity is improved, but manufacturing cost increases and skin effect losses worsen at high frequencies
Solution Approach 1:
The patent divides the single coil into multiple parallel branches, each with its own capacitor. This segmentation allows current to be distributed across multiple thinner wires instead of using one thick wire, reducing skin effect losses while avoiding the high cost and manufacturing complexity of thick non-standard wires.
Solution Approach 2:
The patent introduces capacitors in parallel branches to change the electrical parameters of the circuit. By adjusting capacitance values, the equivalent impedance of each branch is balanced, ensuring uniform current distribution and reducing overall coil loss without requiring thicker wires.
2Reliability
If resonant capacitors are added to parallel coils, then impedance matching is improved, but device complexity increases
Solution Approach 1:
The patent segments the resonant circuit into multiple parallel branches, each with its own capacitor. This segmentation provides independent impedance control for each branch, improving overall impedance matching and current distribution while maintaining a relatively simple modular structure that doesn't significantly increase 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
This configuration effectively reduces loss and improves wireless charging efficiency while maintaining charging rate and freedom, by ensuring equal currents through each branch and minimizing impedance differences.
Implementation Method 1
each parallel branch comprises a coil and a first capacitor which are connected in series; wherein the capacitances of the first capacitors are set to reduce or eliminate an equivalent impedance difference between the parallel branches
Implementation Method 2
Wirelessly charged mobile terminals are increasingly popularized; the mobile terminals are mostly configured with a wireless charging function
Implementation Method 3
due to the skin effect and proximity effect of a high frequency current, when the wire diameter of the winding wire increases to a certain extent, the loss would not be reduced
Data Source
AI summary
A coil module, power transmitting circuit and power receiving circuit are disclosed. The coil module including at least two parallel branches, wherein each parallel branch includes a coil and a first capacitor which are connected in series; the capacitances of the first capacitors are set to reduce or eliminate an equivalent impedance difference between the parallel branches. Therefore, the loss is reduced and the wireless charging efficiency is improved while ensuring the charging rate and the charging degree of freedom.