Offshore Conservator Tank Compartments to Reduce Oil Sloshing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Offshore substations face issues with sloshing movements of insulation liquid in conservator devices due to sea wave motion, which can damage components and cause false alarms, leading to potential failure and high maintenance costs.

Innovation Solution

A conservator device with horizontally divided compartments and flexible barriers that allow air and liquid to flow through porous or open-ended wall members, reducing sloshing and mitigating resonance frequencies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the conservator device uses a single large compartment, then the device complexity is reduced, but sloshing movements increase causing damage to components and false alarms

Engineering Contradiction:
Improveconservator device structureVSAvoidcomponent damage from sloshing
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The conservator device is divided into multiple compartments using vertical wall members, transforming a single large compartment into several smaller ones. This segmentation reduces the amplitude of sloshing movements in each compartment while maintaining the overall conservator function, thereby improving reliability without significantly increasing device complexity

Inventive Principle:
Principle #1Segmentation

2Reliability

If flexible barriers are used to separate air from liquid, then oxygen ingress is prevented, but the barriers are vulnerable to damage from sloshing forces

Engineering Contradiction:
Improveprevention of oxygen ingressVSAvoidbarrier resistance to sloshing forces
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

By dividing the conservator into multiple compartments, the sloshing forces acting on each barrier are significantly reduced compared to a single large compartment. This segmentation allows the use of flexible barriers that can effectively prevent oxygen ingress without being overly vulnerable to damage from hydrodynamic forces

Inventive Principle:
Principle #1Segmentation

3Reliability

If the conservator device is sealed with nitrogen, then oxygen ingress is completely prevented, but the device complexity and cost increase

Engineering Contradiction:
Improveprevention of oxygen ingressVSAvoidconservator device structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The compartmented structure with flexible barriers provides an alternative method to prevent oxygen ingress that does not require complete nitrogen sealing. This approach achieves similar reliability benefits while avoiding the increased complexity and cost associated with fully sealed nitrogen-filled systems

Inventive Principle:
Principle #1Segmentation

4Reliability

If wall members are made solid to reduce sloshing, then sloshing is reduced, but liquid flow through the wall members is blocked

Engineering Contradiction:
Improvereduction of sloshing movementsVSAvoidliquid flow through wall members
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The vertical wall members are designed with porous characteristics that allow liquid to flow through them while still providing structural division to reduce sloshing. This porous design enables the wall members to simultaneously achieve the dual functions of sloshing reduction and liquid permeability

Inventive Principle:
Principle #31Porous 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

Reduces sloshing-induced damage to components, enhances system stability, and minimizes maintenance costs by preventing oxygen ingress and reducing fatigue on barriers.

Implementation Method 1

The one or more wall members are liquid-permeable

Methodology Applied
Scientific EffectPermeation: Permeation

Implementation Method 2

Each respective barrier is flexible and attached to the tank such that the barrier fluidly separates a dry portion of the inner volume of the tank from a remaining portion of the inner volume of the tank

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP4672283A1A conservator device for use with an offshore electrical induction device
Publication Date: 2025.12.31 HITACHI ENERGY LTD
  • EP4672283A1 patent drawingFigure 1~3
  • EP4672283A1 patent drawingFigure 4~5
  • EP4672283A1 patent drawingFigure 6~7

AI summary

A conservator device (1) for use with an electric induction device (2), said electric induction device comprising a liquid-filled volume. The conservator device (1) comprises: a tank (3), one or more wall members (4) provided within an inner volume of the tank (3), said one or more wall members (4) being adapted to horizontally divide the inner volume of the tank (3) into a plurality of compartments (C). One or more of said compartments (C) is provided with a respective barrier (6) being flexible and attached to the tank (3) such that the barrier (6) fluidly separates a dry portion of the inner volume of the tank (3) from a remaining portion of the inner volume of the tank (3), wherein each dry portion of the inner volume of the tank (3) is fluidly connected to ambient air by a first port (8) of the tank (3). The tank (3) comprising a second port (7) adapted to enable a liquid connection between said remaining portion of the inner volume of the tank (3) and a liquid-filled volume of the electric induction device (2). Further, the one or more wall members (4) are liquid-permeable.