Wind farm switching and protection of medium voltage transformers in air insulated technology for substation applications

Introduction

The worldwide demand for renewable energy is growing constantly, with wind power as one of the fastest growing sectors. To meet the current and future needs of network operators, manufacturers and designers of wind power systems need to be able to call on both advanced technologies and in-depth knowledge.



Approach

The wind onshore sector, even being one of the most efficient source of renewable technologies, must focus on continuous cost optimisation process. This we can see either in turbine manufacturers behaviours and in all other installation components including medium voltage components. The demand is going towards more and more bigger turbine power and efficiency that definitely means higher step up transformers cooperating with turbine generators. Additional accent is placed on service and maintaining wind farms in long term perspective since the most common demand for installation life time is at least 20 years.

Main body of abstract

Major global power and distribution manufacturers provides alternative solution starting from compact substations, breakers and fuse-switch combinations. This solutions are based on SF6 insulation technology mostly or like in case of switching devices on vacuum interrupting chambers.
However we see many advantages of above listed products we have not seen significant development in range of fuse-switch combination being worldwide, standard and cost optimised solution for switching and protection of distribution transformers in last decades.
ABB has many years of experience in collaborating with the wind industry and is a leading global supplier of components, systems and services. The range covers everything from customized power components through to the delivery of complete turnkey networks.
The global product portfolio of 36 kV air insulated fuse-switch combination is now expanded with NALFWind™ - a high performance load break switch with integrated fast acting current limiting fuses.
The ABB NALFWind™ 36 kV switch-fuse combination units are specially designed for use in wind electricity distribution environments where special fast acting HRC fuses are required to handle high levels of fault energies to provide protection and isolation on the windfarm electricity network, one of the fastest-growing renewable energy sectors.


Conclusion

The presented solution is very cost-effective proposal for transformer/network protection at 36 kV transformer substation for wind farms. The NALFWind offers high level of protection and is ready for network automation. And outdoor transformer substation provides easy access to all components that supports maintenance process optimization.


Learning objectives
Market applications are based on available technologies that sometimes create application standards due to lack of competitive alternatives. However the technology development is the process that never ends and may surprise us providing safe and also very cost effective solution for the wind industry, that has not been previously possible in this type of air- insulated switching portfolio. Wind market that place more and more attention on cost optimization welcomes this new solution that definitely may become very interesting option for 3 MW installations.