Parallel Helical Coil Reduces Resistance
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Solution Overview
Problem
The existing coil devices for wireless power transfer systems face a challenge in maintaining high power efficiency due to increased electric resistance and subsequent Joule heat generation, which reduces efficiency when the number of coil turns is increased to enhance inductance.
Innovation Solution
The implementation of a power transmission coil device with two helical coils magnetically coupled in parallel, where the first and second conductive wires are connected in parallel to reduce electric resistance and suppress Joule heat generation while maintaining a desired inductance, and the configuration of the coils ensures a balanced magnetic coupling and current distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the number of turns of the coil is increased to increase inductance, then the inductance is improved, but the electric resistance becomes larger and Joule heat generation increases
Solution Approach 1:
The coil is divided into multiple independent coil units (first coil unit, second coil unit, third coil unit, fourth coil unit) with different numbers of turns. These segmented coil units are then connected in parallel to achieve the desired total inductance while reducing overall electric resistance, thereby resolving the contradiction between maintaining inductance and reducing energy loss.
2Reliability
If the number of turns of the coil is increased to increase inductance, then the inductance is improved, but Joule heat generation increases
Solution Approach 1:
The coil is divided into multiple independent coil units (first coil unit, second coil unit, third coil unit, fourth coil unit) with different numbers of turns. These segmented coil units are then connected in parallel to achieve the desired total inductance while reducing overall electric resistance, thereby resolving the contradiction between maintaining inductance and reducing energy loss.
3Reliability
If the number of turns of the coil is increased to increase inductance, then the inductance is improved, but the electric resistance becomes larger
Solution Approach 1:
The coil is divided into multiple independent coil units (first coil unit, second coil unit, third coil unit, fourth coil unit) with different numbers of turns. These segmented coil units are then connected in parallel to achieve the desired total inductance while reducing overall electric resistance, thereby resolving the contradiction between maintaining inductance and reducing energy loss.
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 approach effectively suppresses Joule heat generation while ensuring a desired inductance, improving the power efficiency of the wireless power transfer system by reducing electric resistance and noise interference through the twisted pair cable structure.
Implementation Method 1
A wireless power transfer system has been known as a device for transmitting power. The wireless power transfer system is a power feeding system using electromagnetic induction or magnetic resonance by a coil, etc.
Implementation Method 2
When the electric resistance becomes larger, copper loss occurs, and thus the coil generates Joule heat. When Joule heat is generated, power efficiency decreases.
Data Source
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AI summary
A power transmission coil device includes a first helical coil having a first conductive wire forming a helical shape around an axis, and a second helical coil having a second conductive wire forming a helical shape around the axis, in which the first helical coil is electrically connected in parallel to the second helical coil, and the first conductive wire and the second conductive wire arranged along a direction of the axis.