Braided Coaxial Cable Reducing Inductive Losses
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-performance coaxial cables used for industrial applications experience significant inductive and ohmic losses due to the skin effect at high frequencies, leading to inefficient power transmission and conductor overheating.
Innovation Solution
The coaxial cable design features braided bundles of individual wires with a thin insulation layer, allowing for closer conductor proximity and reduced electromagnetic interference, along with a water-cooled structure to manage heat, thereby minimizing inductive losses and increasing the usable conductor cross-section.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional cable structures with parallel strands are used, then the cable can transmit high currents, but inductive losses and skin effect increase significantly at high frequencies
Solution Approach 1:
The conductor is divided into multiple individually insulated wires (e.g., 19x7x0.2mm) arranged in bundles that form a braid. This segmentation allows each wire to carry current independently, reducing the skin effect and inductive losses by distributing current flow across the entire conductor cross-section rather than concentrating it on the surface.
Solution Approach 2:
The patent transitions from a traditional parallel strand arrangement to a three-dimensional braided structure. The bundles are arranged in a braid pattern with alternating crossing and undercrossing, creating a complex spatial configuration that reduces inductive coupling between adjacent conductors and minimizes the skin effect by distributing current paths in multiple dimensions.
2Loss of energy
If conductor cross-section is increased to reduce ohmic losses, then power transmission capacity improves, but the skin effect becomes more pronounced at high frequencies
Solution Approach 1:
Instead of using a single solid conductor or few large strands, the patent employs numerous thin individually insulated wires (e.g., 19x7x0.2mm configuration). This segmentation ensures that the skin effect is limited to the surface of each thin wire rather than the entire conductor, effectively utilizing the full cross-sectional area for current flow and reducing both ohmic and inductive losses.
Solution Approach 2:
Each individual wire within the bundle is insulated with a thin layer (e.g., electrolacquer), creating localized electrical isolation. This allows the current to flow through the entire cross-section of each wire without being affected by the skin effect from adjacent wires, while maintaining overall conductor flexibility and high-frequency performance.
3Reliability
If insulation layer thickness is increased to prevent voltage flashover, then electrical safety improves, but inductive losses increase due to greater distance between conductors
Solution Approach 1:
The patent uses advanced insulation materials (e.g., EPDM elastic insulation layer) with high dielectric strength, allowing the insulation thickness to be reduced while maintaining the same level of voltage flashover protection. This parameter change in material properties enables closer spacing of conductors, thereby reducing inductive losses without compromising electrical safety.
Solution Approach 2:
The insulation system combines multiple materials with complementary properties: electrolacquer coating on individual wires provides basic isolation, while an EPDM elastic insulation layer provides enhanced flashover protection. This composite approach achieves high reliability with minimal thickness, reducing the distance between conductors and minimizing inductive coupling.
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 design reduces inductive losses by up to 50% and increases the effective conductor cross-section from 20% to 35%, enabling more efficient power transmission and reduced stress on the conductors at high frequencies.
Implementation Method 1
an elastic insulation layer being located between the first and second conductors to prevent a voltage flashover
Implementation Method 2
the first and second electrical conductors are preferably located in a chamber through which liquid can flow
Implementation Method 3
For this purpose, the first and second electrical conductors are preferably located in a chamber through which liquid can flow
Implementation Method 4
the skin effect that occurs at high frequencies leads to high voltage drops in the cable
Data Source
Figure 1
Figure 2
Figure 3~4
AI summary
The invention relates to a coaxial cable (1) for transmitting high currents in the range of several hundred to several thousand amperes at high frequencies, particularly in the kilohertz range, comprising a first electrical conductor (4) for a first current phase and a second electrical conductor (7) arranged coaxially to the first for a second current phase, each formed by a number of ring-shaped bundles (4a, 7a) of a plurality of mutually insulated individual wires, wherein an elastic insulating layer (5, 6) is located between the first and second conductors (4, 7) to prevent voltage flashover. The bundles (4, 7a) of the first and/or second electrical conductor (4, 7) are designed to form a braid. This reduces inductive losses and increases the effectively usable conductor cross-section.