Wind Turbine Generator Coil Repair Without Full Disassembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for repairing wind turbine generators with preformed coils require complete disassembly and result in compromised thermal conductivity, insulation, and service life due to moisture penetration and electromagnetic forces.

Innovation Solution

A method for repairing wind turbine generators by decoupling and replacing defective preformed coils within the generator housing, using connections like screw, plug, or welded joints, and injecting resin to secure new coils, ensuring equivalent thermal conductivity and insulation properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of repair

If the generator is completely disassembled for repair, then the defective coil can be replaced, but the thermal conductivity and insulation are compromised allowing moisture penetration

Engineering Contradiction:
Improvecoil replacementVSAvoidthermal conductivity and insulation
Core Design Contradiction:
Ease of repairVSReliability

Solution Approach 1:

The invention divides the repair process into segments: only the defective coil is removed and replaced, while the rest of the generator remains assembled. The slot insulation is selectively replaced only where needed, rather than completely disassembling and rebuilding the entire generator, thus maintaining thermal conductivity and insulation integrity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The repair applies local quality by replacing insulation materials only in the specific slots where coils are defective, rather than uniformly treating the entire generator. This localized approach preserves the thermal conductivity and insulation properties of unaffected areas while addressing repair needs.

Inventive Principle:
Principle #3Local quality

2Manufacturing precision

If the slot is completely cleared and rebuilt, then the insulation can be restored, but the service life is minimized due to electromagnetic forces causing relative movement

Engineering Contradiction:
Improveinsulation restorationVSAvoidservice life
Core Design Contradiction:
Manufacturing precisionVSDuration of action of stationary object

Solution Approach 1:

The invention applies preliminary action by pre-securing the new coil to the slot insulation using adhesive before inserting it into the slot. This preliminary bonding prevents relative movement between the coil and slot under electromagnetic forces during operation, thereby extending service life while maintaining insulation restoration.

Inventive Principle:
Principle #10Preliminary action

3Ease of repair

If the generator is disassembled and transported to a factory, then repair can be performed, but the cost increases and disassembly is required

Engineering Contradiction:
Improverepair capabilityVSAvoidrepair cost and complexity
Core Design Contradiction:
Ease of repairVSEase of manufacture

Solution Approach 1:

The invention enables self-service repair by providing a repair method that can be performed on-site at the wind turbine location without requiring complete disassembly or transport to a factory. The simplified procedure allows maintenance personnel to replace defective coils directly in the generator, reducing repair costs and complexity.

Inventive Principle:
Principle #25Self-service

4Manufacturing precision

If resin is applied to coating the winding overhangs, then the insulation is improved, but moisture can still penetrate the slot during operation

Engineering Contradiction:
Improveinsulation qualityVSAvoidmoisture penetration
Core Design Contradiction:
Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The invention introduces an intermediary substance - adhesive - that bonds the new coil to the slot insulation. This adhesive layer acts as an additional barrier against moisture penetration while maintaining the insulation quality provided by the resin coating, thereby addressing both insulation and moisture protection requirements.

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

The method allows for cost-effective repair without disassembly, improving thermal conductivity and insulation, reducing moisture sensitivity, and extending the service life of the generator.

Implementation Method 1

ensuring equivalent thermal conductivity and insulation properties

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 2

ensuring equivalent thermal conductivity and insulation properties

Methodology Applied
Scientific EffectElectrical insulation: Dielectric

Data Source

PatentEP4637001A1Method for repairing a generator with form coils, generator and wind turbine
Publication Date: 2025.10.22 WOBBEN PROPERTIES GMBH
  • EP4637001A1 patent drawingFigure 1
  • EP4637001A1 patent drawingFigure 2
  • EP4637001A1 patent drawingFigure 3a~3b

AI summary

Method for repairing a generator with preformed coils, in particular a generator of a wind turbine with preformed coils, comprising the steps of: decoupling (1010) the first and second terminals (18, 19) of a defective preformed coil (11) from two further ones of the plurality of preformed coils (10); separating (1020) the first and second coil heads (14, 16) of the defective preformed coil (11); separating (1030a) a slot closure wedge which closes a slot in which a first leg (12a) of the defective preformed coil (11) is inserted; removing (1040a) the first leg (12a) of the defective preformed coil (11) from the slot (38); inserting (1050a) a first leg (12a) of a new preformed coil (13) with an electrical conductor made of copper or aluminum;Inserting (1060a) a new slot closure wedge (39) into the slot (38) into which the first leg (12a) of the new preformed coil (13) was inserted, wherein the slot (38) is closed by the new slot closure wedge (39) in the direction of the air gap existing between the stator and rotor in the operating state; introducing (1070a) resin into the slot into which the first leg (12a) of the new preformed coil (13) was inserted; connecting (1080) the first leg (12a) to the second leg (12b); and coupling (1090) the first and second terminals to the first terminal and second terminal of the two further preformed coils (10).