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Specialist Materials for Industry and Science

Offshore Wind Energy

Offshore Wind Energy

Offshore Wind Turbine Transformers

Offshore wind energy continues to evolve and grow worldwide. Operating offshore presents its own unique challenges for experts, with dependability and safety being paramount concerns. Potentially corrosive atmospheres test reliability, and failures can result in expensive unplanned maintenance. It is therefore essential to specify a robust, oxygen stable liquid with a long, successful history.

MIDEL 7131 has established a strong reputation in this sector. It is the most popular dielectric fluid in this demanding arena, and its reputation is testament to MIDEL 7131's proven track record as a fire safe, high performance transformer fluid.

Benefits of MIDEL 7131 in Offshore Wind Transformers

Fire Safety

Fire safety is a crucial factor for wind turbine transformers, and MIDEL offers the perfect solution. At >300°C, MIDEL 7131 has a much higher fire point than mineral oil, and its 100% fire safety record greatly reduces the risk to your transformer. It is an FM Global® and UL® listed transformer fluid that is perfectly suited to installation within a turbine.

High Performance

Using MIDEL 7131 has advantages in comparison to installing dry-type transformers because its properties allow for a more compact design - an important consideration where space is limited. MIDEL 7131 filled transformers are also not as susceptible as dry-type systems to damage from vibrations and harmonic frequencies or as sensitive to water, micro-cracks and pollution.

Other benefits of using MIDEL 7131 in wind turbine transformers include:

  • Robust and stable at high temperatures over long periods
  • Suitable for use in hybrid and aramid designs
  • Allows for compact design; ideal for installation in tower or nacelle
  • Very low pour point (-56°C)
  • Self healing
  • Lower no-load losses than cast resin transformers, reducing energy consumption in low wind conditions
  • Excellent lubrication properties
  • Greater moisture tolerance than mineral oil and natural ester
  • No corrosive sulphur
  • Proven up to 433kV in power transformers

Greater Environmental Protection

Reliability a paramount critical factor when it comes to transformer insulation, but in a clean technology sector such as wind energy they should also be environmentally sound. In this respect, fluids such as mineral oil cannot compare to MIDEL 7131 because it is readily biodegradable according to OECD 301 and fully biodegradable according to IEC 61039.

Furthermore, it is non-toxic, not harmful to aquatic life and recoverable/dispersible at sea using standard methods, highlighting MIDEL 7131's suitability for offshore wind turbine transformers.

Any Questions?

The MIDEL team is acknowledged, for its superior customer service delivery. Our multilingual commercial team of transformer liquid experts are always available to provide technical support for our customers. Call +44 (0)161 864 5422 – we’re here to help.

For more information please see our Documents or Contact us.



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Products of M&I Materials Ltd.