On-Load Tap Changer Ring Stack With Single Geneva Drive

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing on-load tap changers face challenges in reliable and efficient switching of tap connections without complex interconnected mechanisms, which can lead to reduced reliability and increased complexity.

Innovation Solution

A switching system comprising a rotatable ring stack with a Geneva mechanism, where a single driving wheel and Geneva ring enable simultaneous rotation of two current carrier rings, avoiding independent rotation and allowing for compact, robust, and reliable switching of both odd and even positions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple independent mechanisms are used to rotate the first and second current carrier rings independently, then each ring can be controlled separately, but the device complexity increases and reliability decreases

Engineering Contradiction:
ImproveIndependent control of current carrier ringsVSAvoidComplexity of interconnected mechanisms
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines the rotation control of the first and second current carrier rings into a single Geneva mechanism. The Geneva ring is mechanically coupled to both rings such that rotation of the Geneva ring causes simultaneous rotation of both current carrier rings, eliminating the need for separate independent control mechanisms while maintaining coordinated operation.

Inventive Principle:
Principle #5Merging (Combining)

2Measurement precision

If complex interconnected mechanisms are used to rotate current carrier rings independently, then precise positioning is achieved, but the switching reliability is reduced

Engineering Contradiction:
ImprovePositioning precision of current carrier ringsVSAvoidSwitching reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent employs a single Geneva mechanism to control both current carrier rings simultaneously, reducing the number of mechanical connections and potential failure points. The Geneva ring is mechanically coupled to both rings through a unified drive system, simplifying the mechanism while maintaining precise positioning capability through the inherent Geneva mechanism geometry.

Inventive Principle:
Principle #5Merging (Combining)

3Adaptability or versatility

If separate driving mechanisms are used for odd and even positions, then independent switching is enabled, but the overall system size and complexity increase

Engineering Contradiction:
ImproveIndependent switching of odd and even positionsVSAvoidSystem size
Core Design Contradiction:
Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent merges the driving mechanisms for odd and even positions into a single Geneva mechanism. The Geneva ring is simultaneously coupled to the first current carrier ring (for odd positions) and the second current carrier ring (for even positions), allowing both sets of contacts to be switched independently through a compact unified structure, thereby reducing overall system size.

Inventive Principle:
Principle #5Merging (Combining)

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 system achieves reliable and efficient switching operations between all tap positions with reduced complexity and size, ensuring continuous power supply during tap changes by using a single Geneva mechanism to drive both current carrier rings uniformly.

Implementation Method 1

the Geneva ring is mechanically coupleable with the driving wheel, such that the Geneva ring is rotatable by the driving wheel

Methodology Applied
Scientific EffectGeneva mechanism: Geneva Drive

Data Source

PatentEP4208884B1Switching system for an on-load tap changer, on-load tap changer and method for switching a tap connection of an on-load tap changer
Publication Date: 2024.03.06 HITACHI ENERGY LTD
  • EP4208884B1 patent drawingFigure 1
  • EP4208884B1 patent drawingFigure 2
  • EP4208884B1 patent drawingFigure 3

AI summary

Switching system for an on-load tap changer, on-load tap changer and method for switching a tap connection of an on-load tap changer A switching system for an on-load tap changer comprises: - a rotatable ring stack (130), wherein the rotatable ring stack (130) is part of an internal Geneva mechanism (121), - a drive system (120), wherein the ring stack (130) comprises: - a first current carrier ring (131) and a second current carrier ring (132) each of which is selectively electrically coupleable to one of a plurality of contact elements (111, 112) of the tap changer (100), and - a Geneva ring (133), wherein the drive system (120) comprises a driving wheel (122), wherein - the Geneva ring (133) is mechanically coupleable with the driving wheel, such that the Geneva ring (133) is rotatable by the driving wheel (122), - the first and the second current carrier rings (131, 132) each are coupled with the Geneva ring (133) such that a rotation of Geneva ring (133) causes a joint rotation of the first and the second current carrier ring (131, 132).