There are many factors influencing transformer oil. All of them need to be checked – to provide a good and reliable work of transformers.
Contact with the atmosphere, high temperature and sunlight – are important factors that affect the quality of oil. And the higher the oxidation of transformer oil, the lower its dielectric strength. Oxidation can be estimated using parameters: reaction of water extract and acid number. They are key quality controls. The first shows the presence of insoluble acids in the oil , and the second – the number of milligrams of potassium hydroxide that is necessary to neutralize all the free acid. A good transformer oil should have a neutral reaction of water extract.
Low temperatures – and the pour point of oil is a very important parameter. The less is the temperature – the more is the viscosity of oil, which is leading to the slow circulation of insulating liquid in the oil-filled electrical equipment
Oil gradually decreases in the transformer tank, caused by evaporation. Therefore, it is necessary to conduct a regular topping up of dielectric fluid.
If during operation of transformer the insulated liquid fails to satisfy set requirements, it is necessary to activate the regeneration process. Regeneration – is a recovery of properties of transformer oils, which prolongs their further use for the intended purpose.
To slow the aging process of oil are used:
- Special thermosiphon filters are used filled with silica gel. They have good absorption properties, continuously removing aging products and restoring insulating liquids.
- Nitrogen protection against oxidation. Nitrogen pillows are generated in the transformer tank, to prevent contact of oil with the air,
In the absence of chemical insoluble impurities, water or coal – insulating liquid can be recovered by using
- sedimentation,
- filtration or
- centrifugation.
When treating insulating fluids it is very important to ensure uninterrupted supply of electricity to consumers. This is possible, either with a backup transformer, or using equipment for regeneration while a transformer is in operation. GlobeCore manufactures such systems.
CMM-R – a regeneration plant, restoring quality of transformer oil to set values by the use of a special sorbent – Fullers Earth. It has a high absorption capacity and removes products of oxidation and aging from the insulating liquid.
After saturation Fuller’s earth is directly restored in the equipment and can be used for further processing of transformer oil.
