Gas Insulation Device Non-Linear Resistive Coating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional gas insulation devices struggle to control the behavior of metal foreign substances at high voltages, as existing insulating coatings either block or permit electric charge movement, leading to uncontrolled floating and partial discharge, especially when the electric field strength exceeds the ionization strength of the insulation gas.

Innovation Solution

A gas insulation device is designed with a dual-layer coating system, where an insulating coat on the tank's inner surface is combined with a non-linear resistive coat containing silicon carbide, which blocks electric charge movement at low voltages and becomes conductive at high voltages to release charges and relax electric field concentrations, preventing metal foreign substance floating and partial discharge.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an insulating coating material is applied to the inner surface of the tank, then movement of electric charge from the tank surface to metal foreign substance is blocked at low voltage, but at high voltage the coating permits charge movement and electric attraction force exceeds the weight of the metal foreign substance causing it to float

Engineering Contradiction:
Improveinsulation performanceVSAvoidvoltage range control capability
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The coating material's electrical resistance dynamically changes with voltage level. At low voltage, the coating maintains high resistance to block charge movement. At high voltage, the resistance decreases to permit charge movement, allowing the coating to adapt its electrical properties based on operating conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The electrical resistance parameter of the coating material changes in response to voltage level. The coating transitions from a high-resistance state at low voltage to a lower-resistance state at high voltage, enabling different functional behaviors across the voltage range while maintaining control over metal foreign substance behavior.

Inventive Principle:
Principle #35Parameter changes

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 controls the behavior of metal foreign substances, enhances voltage-withstanding performance, and improves insulation reliability by blocking charge movement and releasing electric charges to the non-linear resistive coat, reducing tank diameter and electrode area effects.

Implementation Method 1

a coat (3) including an insulation material containing a non-linear resistive material

Methodology Applied
Scientific EffectNon-linear resistance: Electrical Resistance

Implementation Method 2

the non-linear resistive part shows a conductive property in the periphery of the metal foreign substance and an electric charge is released from the metal foreign substance to the non-linear resistive part

Methodology Applied
Scientific EffectConduction: Conduction (electrical)

Implementation Method 3

movement of an electric charge from an inner surface of the tank to a metal foreign substance is blocked by an insulation part

Methodology Applied
Scientific EffectElectrical insulation: Electrical Resistance

Implementation Method 4

the metal foreign substance is charged and moved in a reciprocating manner in a radial direction in the tank due to the influence of the electric field generated by the energized conductor

Methodology Applied
Scientific EffectElectric field: Electric Field

Implementation Method 5

electric attraction force that affects the metal foreign substance

Methodology Applied
Scientific EffectElectrostatic attraction: Electrostatics

Data Source

PatentEP3163701B1Gas-insulated device
Publication Date: 2021.06.09 MITSUBISHI ELECTRIC CORP
  • EP3163701B1 patent drawingFigure 1~2
  • EP3163701B1 patent drawingFigure 3~4
  • EP3163701B1 patent drawingFigure 5

AI summary

Provided is a gas insulation device that includes a grounded metal tank (1) in which an insulation gas is encapsulated; a conductor (2) which is provided in the tank (1), on a surface of which an alumite film (6) on which sealing treatment is performed is formed, and across which a voltage is applied; an insulating coat (101) provided on an inner surface of the tank (1); and a coat (3) that is provided on the coat (101) and that includes an insulation material containing a non-linear resistive material.