Fluted Condenser Bushing Epoxy Flow Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing cast condenser bushings face challenges in filling the condenser core with epoxy due to viscosity increase and potential premature hardening, leading to manufacturing defects and reduced production efficiency.

Innovation Solution

The use of a fluted, corrugated construction with large flute/corrugation size in the condenser layers allows epoxy to flow more freely, reducing the likelihood of voids and enabling faster filling of the mold before viscosity increases, using a conductor with a cork layer and PTFE tape to control epoxy bonding, and employing a method of wrapping conductive sheets around the conductor in a spiral fashion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If epoxy is used to fill the condenser core, then the condenser layers are encapsulated and electrically insulated, but the epoxy viscosity increases and hardens prematurely, making it difficult to fill the mold completely

Engineering Contradiction:

Improveencapsulation and electrical insulationVSAvoidmold filling speed

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The patent changes the physical parameters of the condenser core structure by introducing flutes with specific dimensions (depth, width, spacing) to modify how epoxy flows and distributes during the casting process, enabling complete mold filling before epoxy hardening

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The condenser core is segmented into multiple fluted sections that create channels for epoxy flow, allowing the epoxy to penetrate and fill the entire condenser core volume systematically rather than as a single mass, which improves filling efficiency

Inventive Principle:

Principle #1Segmentation

2Manufacturing precision

If the epoxy fills the mold slowly, then the epoxy can be properly distributed, but the epoxy hardens prematurely, causing voids and manufacturing defects

Engineering Contradiction:

Improveepoxy distribution uniformityVSAvoidabsence of voids and defects

Core Design Contradiction:

Manufacturing precisionVSReliability

Solution Approach 1:

The fluted structure segments the epoxy filling process into multiple flow paths through the flutes, ensuring uniform distribution of epoxy throughout the condenser core while maintaining continuous flow that prevents void formation

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The flutes create local variations in the condenser core structure that guide epoxy flow to specific areas needing coverage, ensuring uniform distribution while the overall design maintains continuous filling to prevent defects

Inventive Principle:

Principle #3Local quality

3Device complexity

If traditional smooth condenser core construction is used, then the structure is simple, but the epoxy cannot flow freely, leading to filling difficulties and production inefficiency

Engineering Contradiction:

Improvecondenser core structureVSAvoidproduction efficiency

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The condenser core is segmented into fluted sections that create flow channels, transforming the simple smooth structure into a segmented configuration that actively guides epoxy flow and improves filling efficiency

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The fluted structure creates a porous-like network of channels within the condenser core that facilitates epoxy penetration and flow, improving filling capability while maintaining structural integrity

Inventive Principle:

Principle #31Porous materials

Data Source

PatentUS10325700B1Condenser bushing, transformer and method for producing a condenser bushing

Publication Date: 2019.06.18 HITACHI ENERGY LTD

AI summary

A cast condenser bushing includes an electrical conductor; a plurality of condenser layers disposed about the conductor, each condenser layer including a fluted, corrugated electrical insulator and a conductive sheet; and epoxy encapsulating the plurality of condenser layers and forming an epoxy casting, wherein the epoxy is disposed within and between each condenser layer.