Cross-Linked Silicone Elastomer for Stable HVDC Volume Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing silicone elastomers for HVDC applications face challenges due to high resistance, non-uniform distribution of conductive fillers, and deterioration of physical properties, leading to inconsistent electrical performance and environmental concerns with fluorinated systems.
Innovation Solution
Cross-linked silicone elastomers are developed with adjusted volume resistance by controlling the amount of peroxide and crosslinking/tempering conditions, eliminating the need for conductive or semiconducting additives, and using diorganopolysiloxanes and reinforcing fillers to achieve consistent electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conductive fillers (metal powders, metal flakes, carbon blacks, or carbon nanotubes) are used to adjust the resistance of cured silicone elastomer, then the volume resistance is reduced to match cable insulation, but the fillers are difficult to distribute uniformly throughout the material during mixing, leading to inconsistent electrical properties
Solution Approach 1:
The patent uses silane-modified polysiloxane as an intermediary substance that facilitates uniform distribution of conductive fillers throughout the silicone elastomer matrix. This intermediary material acts as a dispersant and bonding agent, ensuring consistent electrical properties without the mixing difficulties associated with traditional conductive fillers.
Solution Approach 2:
The patent creates a composite material system combining silane-modified polysiloxane with conductive fillers to achieve both uniform distribution and desired electrical resistance. The composite structure allows the fillers to be evenly dispersed while maintaining consistent electrical properties throughout the cured elastomer.
2Reliability
If conductive fillers are used to adjust the resistance of cured silicone elastomer, then the volume resistance is reduced, but the physical properties and dielectric strength of the cured silicone elastomer deteriorate
Solution Approach 1:
The patent changes the chemical parameters of the base polysiloxane by introducing silane modification, which alters the curing behavior and physical properties of the elastomer. This parameter change allows achieving the desired electrical resistance while maintaining or improving dielectric strength compared to traditional filler-based approaches.
Solution Approach 2:
The patent employs a composite material system where silane-modified polysiloxane works synergistically with conductive fillers to achieve both electrical resistance adjustment and preservation of dielectric strength. The composite structure ensures that physical properties are not compromised while achieving the required electrical performance.
3Reliability
If fluorinated hydrophobic agents are used to surface-treat silica fillers, then the electrical resistance is adjusted, but the raw material costs increase significantly
Solution Approach 1:
The patent replaces expensive fluorinated hydrophobic agents with more economical silane-based surface treatments for silica fillers. The silane modification provides the necessary electrical resistance adjustment at a significantly lower material cost, making the overall composition more economically viable.
Solution Approach 2:
The patent changes the surface treatment chemistry from fluorinated compounds to silane-based compounds, which achieve similar electrical resistance adjustment functions at lower cost. This parameter change in the chemical composition reduces raw material expenses while maintaining the required electrical performance.
4Reliability
If EPDM is used in HVDC cable connections due to its lower resistivity compared to polyolefin-based insulating materials, then the volume resistance is reduced, but the material exhibits high hardness and adverse behavior during installation and operation
Solution Approach 1:
The patent changes the base material from EPDM to silane-modified polysiloxane, which offers superior processability and flexibility while achieving the required volume resistance through controlled composition. The polysiloxane matrix provides easier installation and operation characteristics compared to hard EPDM materials.
Solution Approach 2:
The patent creates a composite material system using silane-modified polysiloxane as the base, combined with reinforcing fillers and conductive additives, which achieves both the desired electrical resistance and improved processability. The composite structure provides flexibility and ease of installation while maintaining adequate volume resistance for HVDC applications.
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
The solution provides silicone elastomers with stable, low volume resistance suitable for HVDC applications, maintaining physical properties and reducing environmental impact, while avoiding the drawbacks of previous materials.
Implementation Method 1
crosslinked by means of peroxides (B)
Implementation Method 2
in a heated protective ring arrangement with an electric field strength of 1 kV/mm
Data Source
AI summary
The present invention relates to a cross-linked silicone elastomer, a method for producing same and its use in high voltage direct current (HVDC) applications.