Design and material selection of wind turbine generator transformers

by C Carelsen, M Hlatshwayo, J Haarhoff and G Stanford, Powertech Transformers

 

Published in: Transformers and Substations Handbook: 2014

Chapter 1: Design and manufacture of transformers - page 20

Enquiries: Email:
Carel.carelsen@pttransformers.co.za
Mluleki.hlatshwayo@pttransformers.co.za
Gareth.stanford@pptransformers.co.za
Johan.haarhoff@pptransformers.co.za

 

Read the full article on Design and material selection of wind turbine generator transformers in PDF format.

 

Wind turbine generator transformers are subject to different operating conditions from distribution and power transformers. In the electrical design, there are different fast transients, harmonics and non-sinusoidal loadings, and different loading factors that need to be considered. From a mechanical design perspective, the dynamic load and losses result in a different drive for the design and testing criteria. These changes bring about the need to re-examine the materials used, such as the insulation paper for thermal hot-spots, cooling oil for environmental reasons, or the core steel to optimise losses.

Electrical design: The operating conditions of wind step-up transformers are distinct from those of distribution and power transformers. Their designs should be such that they withstand amongst others: very fast transients, harmonics and non-sinusoidal current loading, loading factors and frequency variations.

Mechanical design: Transformer performance can only be achieved if there is perfect harmony between the electrical and mechanical designs. The mechanical design complements the electrical design by means of design concept and material choices, to achieve the most cost effective design to suit customer specifications, and reduce the carbon footprint (losses).

Transformer specifications such as IEC 60076, usually omit specific material requirements, focusing rather on design and performance. Wise selection of materials can improve the design of the transformer in term of performance and cost.

 

Take note

  • Wind turbine generators are subject to different operating conditions from distribution and power generators.
  • Wise material selection can improve the cost and performance of the design.
  • Losses for wind turbine transformers should be as low as possible.