Coil Component Winding Asymmetry for Stray Capacitance Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Common mode choke coils experience increased mode conversion characteristics due to stray capacitance between wires, leading to asymmetry in signal propagation and mode conversion, which affects the performance of the coil component.
Innovation Solution
The coil component is designed with a specific winding configuration where the first wire is wound as a first layer in contact with the winding core, and the second wire is wound as a second layer on the outside with parts fitted into recesses between the first wire's turns, creating 0.5-displacement and 1.5-displacement regions along the axis, balancing slant capacitances between the wires.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If two wires are wound around a winding core portion with substantially the same number of turns, then the coil component achieves balanced inductance, but stray capacitance between the wires causes mode conversion and signal propagation asymmetry
Solution Approach 1:
The patent applies asymmetry by intentionally creating different winding configurations for the first and second wires. Specifically, the first wire is wound with a first number of turns while the second wire is wound with a second number of turns that differs from the first, and they are positioned at different radial distances from the winding core portion. This asymmetric design compensates for the harmful stray capacitance effects by creating intentional imbalance that counteracts the mode conversion phenomenon, thereby improving signal propagation symmetry.
2Ease of manufacture
If the first wire is wound as a first layer in contact with the winding core and the second wire is wound as a second layer on the outside, then the winding structure is simplified, but stray capacitance between adjacent turns increases
Solution Approach 1:
The patent resolves the contradiction by transitioning from a two-dimensional planar winding arrangement to a three-dimensional spatial configuration. The first wire is wound at a first radial distance from the winding core portion while the second wire is wound at a second radial distance that differs from the first. This dimensional change in radial positioning reduces the proximity between adjacent turns of different wires, thereby decreasing stray capacitance while maintaining the simplicity of the layered winding structure.
3Ease of manufacture
If both wires are wound at the same radial distance from the winding core portion, then the manufacturing process is simplified, but signal propagation asymmetry and mode conversion occur
Solution Approach 1:
The patent applies asymmetry by intentionally creating different winding configurations for the first and second wires. Specifically, the first wire is wound with a first number of turns while the second wire is wound with a second number of turns that differs from the first, and they are positioned at different radial distances from the winding core portion. This asymmetric design compensates for the harmful stray capacitance effects by creating intentional imbalance that counteracts the mode conversion phenomenon, thereby improving signal propagation symmetry.
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 reduces stray capacitance between the wires, minimizing mode conversion characteristics and improving the coil's performance by balancing signal propagation asymmetry.
Implementation Method 1
a first wire and a second wire which are helically wound around a winding core portion with substantially the same number of turns as each other
Implementation Method 2
The wires 43 and 44 are composed of copper wires with insulation coating
Data Source
AI summary
A 0.5-displacement region in which a first wire and a second wire are displaced by 0.5 turns from each other, and a 1.5-displacement region in which the first wire and the second wire are displaced by 1.5 turns in an opposite direction to a 0.5-displacement region are distributed along an axis direction on a winding core portion. The sum of the number of turns of the second wire located in the 0.5-displacement region being twice or more and five times or less than the sum of the number of turns of the second wire located in the 1.5-displacement region.