Transformer Winding Stiffness Zoning for Vibration Noise Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Transformers generate significant noise due to symmetric vibrations in their windings, which are transmitted to the transformer tank, causing acoustic power issues at operating frequencies like 50 Hz and 60 Hz.

Innovation Solution

A winding design with multiple stiffness portions along the coil axis, where the middle portion has a higher stiffness than the ends, achieved by using spacers with varying moduli of elasticity, particularly using stiffer steatite for the middle portion to dampen vibrations and reduce noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If a single uniform winding portion is used, then the manufacturing is simple, but the noise emissions are significant due to symmetric vibrations

Engineering Contradiction:
Improvenoise emissionsVSAvoidwinding structure complexity
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The winding is divided into multiple winding portions (first, second, and third portions) with different stiffness characteristics along the coil axis. This segmentation allows different portions to have optimized mechanical properties, with the third portion having greater stiffness to reduce symmetric vibrations and noise emissions while maintaining overall structural integrity

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different winding portions are assigned different local stiffness properties. The third winding portion, located in the middle of the coil axis, has greater stiffness than the first and second portions. This local quality differentiation targets the specific region where symmetric vibrations cause the most noise, providing vibration reduction where needed without unnecessarily complicating the entire winding structure

Inventive Principle:
Principle #3Local quality

2Object-affected harmful factors

If the middle portion of the winding is made stiffer to reduce vibrations, then the noise emissions are reduced, but the manufacturing complexity increases

Engineering Contradiction:
Improvenoise emissionsVSAvoidwinding assembly ease
Core Design Contradiction:
Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The winding is segmented into distinct portions with the third portion having different stiffness characteristics. This segmentation enables targeted vibration reduction in the middle section while keeping the end portions simpler, balancing noise reduction performance with manufacturing feasibility

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The stiffness parameter is changed locally in the third winding portion compared to the first and second portions. By adjusting the stiffness parameter only where needed (in the middle portion), the design achieves vibration reduction without requiring a complete redesign of the entire winding structure, thus maintaining ease of manufacture for the majority of the winding

Inventive Principle:
Principle #35Parameter changes

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 design effectively reduces noise emissions by dampening the largest movements of the winding, resulting in a significant reduction in acoustic power, as shown in simulated results with noise reduction of at least -3.5 dB at 100 Hz.

Implementation Method 1

arranging a third winding portion having a greater stiffness in the middle part of the winding reduces/dampens the movement of the winding and thereby reduces noise emissions

Methodology Applied
Scientific EffectVibration damping: Damping

Data Source

PatentEP4322189A1A winding, a transformer and a transformer arrangement
Publication Date: 2024.02.14 HITACHI ENERGY LTD
  • EP4322189A1 patent drawingFigure 1
  • EP4322189A1 patent drawingFigure 2~3
  • EP4322189A1 patent drawingFigure 4

AI summary

The disclosure relates to a winding (110) for a phase winding of a transformer (20). The winding (110) comprises a plurality of winding portions (116) arranged along a coil axis (z). The plurality of winding portions (116) comprise a first winding portion (116a) arranged at a first end (110a) of the winding (110) and a second winding portion (116b) arranged at a second end (110b) of the winding (110). The winding (110) further comprises at least a third winding portion (116c) arranged along the coil axis (z) between the first winding portion (116a) and the second winding portion (116b). The first winding portion (116a) and the second winding portion (116b) have a first winding portion stiffness as seen along the coil axis (z) and the at least third winding portion (116c) has a second winding portion stiffness as seen along said coil axis (z). The second winding portion stiffness is greater than the first winding portion stiffness. The disclosure also relates to a transformer (20) comprising the winding (110) and to a transformer arrangement comprising the transformer (20).