Aliphatic Polyamide Transformer Insulation Resists Moisture and Heat

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current cellulosic insulation materials in transformers are prone to thermal degradation, moisture absorption, shrinkage, and chemical instability, leading to reduced mechanical and electrical strength, and are adversely affected by moisture and heat, which accelerates aging and degrades electrical qualities.

Innovation Solution

The use of aliphatic polyamide insulation material, comprising aliphatic polyamide, thermal and chemical stabilizers, and nano-fillers, which provides enhanced thermal and chemical stability, improved moisture resistance, and increased dielectric strength, allowing for better heat dissipation and mechanical reinforcement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If cellulosic insulation materials are used in transformers, then cost is reduced and reasonable performance is achieved, but thermal degradation and oxidative and hydrolytic attack vulnerability increase

Engineering Contradiction:
ImprovecostVSAvoidthermal degradation resistance
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent uses aliphatic polyamide as a composite material that combines multiple desirable properties: inherent moisture resistance, thermal stability, and mechanical strength. This single material replaces the conventional cellulosic materials and resolves the contradiction by providing both reliability and manufacturability without the drawbacks of the former.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The invention changes the material parameter from cellulosic to aliphatic polyamide, which fundamentally alters the chemical and physical properties. This parameter change enables the insulation to resist thermal degradation and moisture while maintaining ease of manufacture and assembly.

Inventive Principle:
Principle #35Parameter changes

2Ease of manufacture

If cellulosic insulation materials are used in transformers, then low cost is achieved, but moisture absorption and electrical strength degradation increase

Engineering Contradiction:
ImprovecostVSAvoidmoisture absorption
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

Aliphatic polyamide is a composite material with inherent hydrophobic properties that resist moisture absorption. This material property directly addresses the contradiction by eliminating the hygroscopic nature of cellulosic materials while maintaining cost-effectiveness and manufacturing simplicity.

Inventive Principle:
Principle #40Composite materials

3Temperature

If cellulosic insulation materials are exposed to heat, then thermal energy is present in the system, but aging rate increases and electrical qualities degrade

Engineering Contradiction:
Improveheat dissipationVSAvoidservice life
Core Design Contradiction:
TemperatureVSDuration of action of stationary object

Solution Approach 1:

The material parameter change from cellulosic to aliphatic polyamide fundamentally improves thermal stability. The new material maintains its mechanical and electrical properties at elevated temperatures, allowing the transformer to operate at higher temperatures without accelerated aging, thus extending service life while maintaining effective heat dissipation.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

Aliphatic polyamide is a thermally stable composite material that resists thermal degradation. This material property enables the insulation to withstand operating temperatures without the rapid aging and electrical quality degradation associated with cellulosic materials.

Inventive Principle:
Principle #40Composite materials

4Reliability

If cellulosic insulation materials are used, then reasonable performance is achieved, but mechanical strength reduction due to moisture content increases

Engineering Contradiction:
Improveinsulation performanceVSAvoidmechanical strength
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

Aliphatic polyamide is a composite material with inherent moisture resistance that maintains mechanical strength in humid environments. This material property directly resolves the contradiction by providing both reliable insulation performance and sustained mechanical strength without the moisture-induced degradation of cellulosic materials.

Inventive Principle:
Principle #40Composite materials

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 aliphatic polyamide insulation material significantly improves the performance of transformers by maintaining mechanical strength and electrical insulation properties even under high temperatures and moisture exposure, reducing aging rates and enhancing thermal conductivity, thus extending the transformer's operational life.

Implementation Method 1

The internal turn insulation is generally placed directly on the rectangular magnet wires and wrapped as paper tape... The purpose of these spaces is to remove the heat from the core and coil structure through convection of the medium, and also help to improve the insulation strengths

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

Cellulose has a strong affinity for water (hygroscopic) and thus will not share the moisture equally with the insulating liquid. The moisture absorption process is considerably slowed after the cellulose has been oil impregnated

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Data Source

PatentEP2606498B1Improved polyamide electrical insulation for use in liquid filled transformers
Publication Date: 2020.04.15 WEINBERG MARTIN
  • EP2606498B1 patent drawingFigure 1~4
  • EP2606498B1 patent drawingFigure 5~7

AI summary

A transformer assembly is provided that includes a housing, transformer oil disposed within the housing, a plurality of coils of electrically conductive wire, and aliphatic polyamide insulation material operable to insulate the coils disposed within the oil. The plurality of electrically conductive coils is disposed in the housing and in contact with the transformer oil. The aliphatic polyamide insulation material includes stabilizing compounds and nano-fillers. The stabilizing compounds provide thermal and chemical stability for the insulation material.