Latest generation of Environmentally Safe Transformers

Bio-SLIM®: Features and Benefits:

The Bio-SLIM® transformers share the following main features with the SLIM® range:
> they are up to 30 % smaller and lighter than conventional units with the same power ratings;
> they offer a 30 % higher power rating than a conventional transformer of the same volume;
> they can accept higher overloads, steep voltage surges, harmonics, transient phenomena, rapid load variations;
> they withstand a broader range of operating temperatures;
> they have up to 50 % lower no-load loss than dry-type and cast resin transformers; load loss is comparable;
> They produce less noise and emit a much lower electro-magnetic field than drytype and cast resin transformers thanks to their earthed tank;
> They can withstand more severe climatic conditions than the dry-type and cast resin transformers and need no special expensive conditioned enclosures.
These features result in numerous benefits for SLIM® and Bio-SLIM® users:
> these transformers can be installed in restricted spaces (in tower, in nacelle); are easier to transport, handle and remove;
> they are highly reliable, even in extreme conditions; that means less maintenance,fewer repairs, less downtime;
> they have an extended lifetime;
> they have a lower total cost of ownership (including installation, peripherals, insurance, maintenance, safety equipment).
The added value of the Bio-SLIM® comes from the use of a non-hazardous fully bio-degradable transformer fluid, which allows it to be used in environmentally sensitive locations, such as offshore and in water-catchments.
Esters are closer to mineral oils than to silicone fluid in their electrical and cooling performance and in their material compatibility. This allows a further optimization of the SLIM® design and has enabled CG Power Systems to extend the SLIM® range into the high-voltage (>36 kV) field.
SLIM® and Bio-SLIM® transformers, with their homogeneous insulation based on DuPont™ NOMEX® high-temperature insulation systems, both fully comply with the latest IEC 60076-14 standard.


Industry Leaders

Several prominent industry leaders have combined their know-how to create the Bio-SLIM® transformer. DuPont, with an unmatched talent in developing high-performance synthetic materials, contributed NOMEX® thermal insulating technology. The chemical industry has supplied an organic ester (such as MIDEL® 7131) as a non-hazardous, bio-degradable dielectric fluid. CG Power Systems, with acknowledged transformer engineering skills, has integrated these materials in an optimized design, utilizing their outstanding characteristics.
NOMEX® withstands high temperatures
NOMEX® thermal insulation technology is based on the use of DuPont™ NOMEX® paper and/or pressboard.
This material’s unique balance of electrical, thermal, physical and chemical properties results in a combination of economic, safety and environmental benefits in transformers, including improved reliability, more compact dimensions, lower weight, and greater reserve capacity to handle overloads.
NOMEX® withstands a continuous temperature of 220 °C with negligible thermal aging.
Synthetic ester as per IEC 61099 is the preferred dielectric fluid for transformers in environmentally sensitive locations.
The Federal German Office for the Environment has classified it as ‘non-water-hazardous’ and it is recognized
as ‘readily bio-degradable’ according to OECD standards.
Its electrical stability allows it to be operated at voltages above the medium voltage range (i.e. >36 kV).
Originally developed as an environmentally friendly replacement for polychlorinated biphenyls, synthetic esters
are fully recyclable, are halogen-free, are Class K3 as per IEC 61100 (fire point >300 °C and net calorific value
< 32 MJ/kg) and have excellent dielectric properties.
Experience Counts
Although this combination of materials is new, the Bio-SLIM® uses tried-and tested technology. NOMEX® was introduced more than 40 years ago; CG Power Systems’ experience with it goes back to the 1980s. Synthetic esters have been used in thousands of transformers without any reported fire incident since 1978;CG has been using it since 1994. Over 5,400 SLIM® transformers (>13,000 MVA) have been installed in various demanding applications, many of them in wind turbines, both on land and offshore.
CG Power Systems and the Environment
Emission-free wind turbines are economically the most promising source of renewable energy. Wind farms offshore and on land are sprouting in many parts of the world, playing a growing part in safeguarding our environment. Striving to make wind turbines even safer in environmental terms, CG Power Systems has developed the Bio-SLIM® range of transformers. These compact, high-performance transformers share the main features of the SLIM® range. Now, in addition, the Bio-SLIM® is cooled by a fully bio-degradable ester, an environmentally safe alternative to other dielectric fluids.