What needs to be considered during offshore transformer service?

Transformers are the centrepiece of every wind turbine - including offshore wind farms. Although they are constructed differently to onshore transformers, they convert the electricity generated in the same way as onshore transformers and ensure that the electricity produced can be fed into the grid. In order to guarantee this important function safely and economically, even offshore, the transformers and their insulating oils must be in perfect condition. Read on to find out how you can eliminate unnecessary maintenance in this context and enable efficient offshore transformer maintenance with trained specialists. 

The offshore wind industry is a promising area of renewable energy and plays a central role in the energy transition concept. The topic is becoming increasingly important now that many countries have committed to reducing carbon emissions and switching to more sustainable energy sources.

This is why the diagnosis and maintenance of offshore transformers is important and will increase

Offshore wind farms, with their ability to take advantage of the steadier and stronger winds at sea and convert them into energy, represent a significant step forward in achieving sustainability goals. At the same time, the harsh marine environment is very challenging for all installations, especially for critical components such as transformers.

1. Ensure that offshore transformers operate at maximum efficiency
The salty air, high humidity and constant exposure to water require robust protective measures for transformers and their insulating oils. In addition to infrequent, essential on-site maintenance, these include the use of modern diagnostic tools to recognise signs of wear, corrosion or contamination in good time.
 
2. The number of offshore wind farms is growing rapidly
Offshore wind power capacity in the North Sea is set to increase to 120 GW by 2030 and 300 GW by 2050 - nine North Sea states (Belgium, Denmark, Germany, France, the UK, Ireland, the Netherlands, Norway and Luxembourg) already agreed on this in 2023. With these ambitious targets, the number and quantity of transformers, their insulating oils and the associated diagnostic and maintenance tasks will also increase.

3. First transformer maintenance intervals within the next 10 years:
All offshore transformers already in use are expected to be subject to their first maintenance within the next decade. This forecast emphasises the urgency of integrating advanced diagnostic and maintenance protocols. 

Continuous monitoring, including frequent, fully automated oil analyses, is recommended

The insulating oil in offshore transformers must be able to withstand high demands. If the transformer oil is no longer able to fulfil its tasks, this can lead to serious damage and extremely expensive failures.

To counteract this, regular, fully automated oil analyses and fully automated monitoring are recommended, especially offshore. This procedure ensures the operational safety and efficiency of offshore wind turbines and significantly extends the service life of transformers. 

It also allows offshore maintenance work to be organised in a more targeted and efficient manner.

Fully automatic monitoring systems ensure that operators reduce operating costs and optimise maintenance schedules without constant manual monitoring:

• These monitoring systems recognise trends and predict failures before they occur! 

Due to the high level of planning and extreme costs associated with offshore transformer maintenance, fully automated oil analyses and monitoring should be standard. This not only minimises the risk of catastrophic failure, but also significantly reduces potential downtime and costs.

On-site maintenance with professionally trained staff: How to avoid damage and expensive breakdowns during offshore transformer maintenance

If maintenance is recommended based on the results of the analysed data, the insulating oil of the transformer can be processed or regenerated by experienced staff.

Ensuring efficiency and safety with comprehensive checks and training

Offshore platform work is carried out by specially trained professionals. They have the necessary knowledge and experience to overcome the unique challenges of offshore environments and ensure that transformer maintenance is carried out safely and efficiently. 

Detailed health checks, such as cardiovascular tests, are standard to ensure the suitability and health of personnel. In addition, technical teams receive close training to keep them up to date with the latest technology and safety protocols.

Read the following article to find out which offshore operations Electrical Oil Services (EOS^®) can handle with regard to transformer oils and how the EOS^® experts proceed:

• EOS^® Offshore Services: Pioneering work under extreme conditions
  
  

Conclusion

Insulating oil in offshore transformers has the same functions as in onshore transformers: it serves as an electrical insulation medium and cools the transformer. The insulating oil in offshore transformers must be able to withstand high demands - if it is no longer able to fulfil its tasks, this can lead to serious damage to transformers and very expensive failures.

Fully automated oil analyses and fully automated monitoring should therefore be standard in order to eliminate unnecessary maintenance and enable efficient offshore transformer maintenance with highly trained specialists.

In this way, you can also reduce the maintenance costs of your offshore transformers and increase the safety and reliability of offshore wind turbines!

Even more interesting facts: Did you know that Electrical Oil Services (EOS^®) collects used insulating oil, recycles it and returns it to the cycle in as-new condition? We call this reuse of insulating oil on a sustainable basis the EOS^® Closed Loop model.

The following blog article presents the proven concept:

• How the circular economy works: the EOS^® Closed Loop model