On-load tap changer gear coupling for space-constrained installation

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Solution Overview

Problem

Existing on-load tap-changers face challenges in being space-efficient and adaptable to varying spatial conditions during transport and installation, particularly when replacing or transporting transformers with limited space constraints.

Innovation Solution

The on-load tap-changer design incorporates a direct mechanical coupling between gears, allowing simultaneous actuation of the selector and diverter switch units by a single drive shaft, with a flexible arrangement of the motor drive and control cabinet to accommodate varying spatial requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the motor drive and control cabinet are mounted externally on the transformer housing, then the on-load tap-changer can be operated independently, but the space required during transport and installation increases

Engineering Contradiction:
Improveindependent operation capabilityVSAvoidspace during transport
Core Design Contradiction:
Ease of operationVSVolume of moving object

Solution Approach 1:

The control cabinet is mounted inside the transformer housing, nesting one component within another. This eliminates the need for external mounting space while maintaining independent operation capability, as the control cabinet can still function autonomously within the transformer's internal space.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The transformer housing serves dual functions: as the protective enclosure for the transformer and as the mounting structure for the control cabinet. This multi-functionality reduces the need for additional external space while maintaining operational independence.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Device complexity

If the on-load tap-changer is designed with fixed mounting configuration, then the structure is simplified, but the adaptability to different spatial conditions at installation site is reduced

Engineering Contradiction:
Improvemounting structureVSAvoidspatial adaptation capability
Core Design Contradiction:
Device complexityVSAdaptability or versatility

Solution Approach 1:

The mounting configuration is made adjustable rather than fixed. The control cabinet can be positioned at different locations on the transformer housing and the drive shaft can be coupled to different gears, allowing adaptation to various spatial conditions while maintaining relatively simple structural elements.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The mounting system is divided into separate, independently adjustable components. The control cabinet mounting position can be adjusted separately from the drive shaft coupling position, allowing flexible adaptation to different spatial requirements without redesigning the entire structure.

Inventive Principle:
Principle #1Segmentation

3Productivity

If the drive shaft is coupled to both gears simultaneously, then both selector and diverter switch are actuated together, but the mechanism complexity increases

Engineering Contradiction:
Improveswitching operation efficiencyVSAvoidgear coupling mechanism
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

A coupling mechanism serves as an intermediary between the drive shaft and the two gears. This coupling allows the drive shaft to transmit motion to both gears simultaneously or selectively, enabling coordinated actuation of both switches while keeping the individual gear mechanisms relatively simple.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 design enables space-saving installation and transport of the tap-changer, allowing flexible adaptation to different spatial conditions at the installation site and during transport, optimizing space utilization in vehicles or substations.

Implementation Method 1

The first gear and the second gear are directly mechanically connected to one another such that the gears can be actuated simultaneously

Methodology Applied
Scientific EffectMechanical coupling: Gear

Data Source

PatentEP4042461B1On-load tap changer
Publication Date: 2025.08.20 REINHAUSEN GMBH DE
  • EP4042461B1 patent drawingFigure 1~2
  • EP4042461B1 patent drawingFigure 3A~3B
  • EP4042461B1 patent drawingFigure 4A

AI summary

An on-load tap-changer (10) for switching, without interruption, between winding taps (N1,...NJ,... NN) of a tapped transformer (1), said on-load tap-changer comprising: - at least one selector unit (30) for preselecting, without power, a designated winding tap (NJ); - at least one load transfer switch unit (40) for actually transferring a load from the previous winding tap (NJ-1) to the preselected winding tap (NJ); - at least one gear mechanism (50) comprising a first gear (31) and a second gear (41), said first gear (31) being associated with the selector unit (30) and said second gear (41) being associated with the load transfer switch unit (40); - and a driveshaft (60) that is operated by a motor drive (70), wherein: - the first gear (31) and the second gear (41) are directly mechanically operatively connected to each other so that the gears (31, 41) are operated simultaneously; - and the driveshaft (60) can drive either the first gear (31) or the second gear (41).