Transformer oil filtration improves insulation properties, increases longevity of the transformers, minimizes breakdown risks and enhances returns on investment. Failing filtration process, the transformer oil is vulnerable to forming electric arc which causes breakdown of the system.
Also overheating, electric discharge caused by ionisation of fluid and decreased insulation which hampers the transformer oil performance and authenticity.
Transformer oil filtration
In this next gen world where power is an inevitable part of human life, transformers gain equal prominence and are the backbone of high voltage power transmission. They step up or decrease voltage and ensure smooth supply of electricity.
Consequently, transformer maintenance is vital to ensure safety and detect faults before they turn hazardous. Besides, expenses related to repair works are also reduced which in turn proves to be good returns to transformer asset investments besides avoiding interruptions in power supply. Transformer maintenance could be either routine or based on requirement. Routine maintenance is known as preventive maintenance.
Transformer oil plays an important role in functioning of transformers since the oil surrounding the coils provide cooling, insulation besides safeguarding against corona and arcing which in turn might ignite fire or create electric sparks. Transformer oil is important for the functioning of transformers.Timely maintenance of transformer oil avoids replacement of insulating fluids and restores functionality.
Transformer oil filtration is a process in which solid particles, dissolved gases and moisture are eliminated. During usage, the oil absorbs oil and gets polluted by dirt and ageing products. Not only used oil, even unused fresh oil has probabilities of absorbing moisture from the air or getting polluted while being stored in barrels.
When the moisture content increases, the insulating efficiency of the oil is reduced. The electric properties of the oil are restored only through procedures like filtering, dehydration and degassing.
Consequences of transformer oil deterioration
The increasing requirements of transformers increase the demand for better dielectric strength and lower residual water of transformer oil. The timely treatment of insulating oil enhances insulation of the transformer. Failing such treatment, transformer failures occur due to arcing, overheating, corona discharges and diminished insulation strength.
Quality parameters of transformer oil
The prescribed attributes of the following elements decide the quality of transformer oil. They are colour, dielectric breakdown voltage, dissolved gas analysis, dissolved metals, flash point, interfacial tension, Furanic compounds, Karl Fischer moisture, liquid power factor, neutralization number, oxidation inhibitor content, polychlorinated biphenyls content, relative density, resistivity and visual examination.
Filtration process
The filtration machine comprises of inlet pump, filters, heaters, ionic reaction column, degassing and dehydration chamber, discharge pumps and vacuum pumps. The inlet pump which is protected against overpressure build-up is tested for vacuum. The provision of interlocking arrangement between inlet pump and high level float switch controls excessive rise of oil in the degassing and dehydration chamber.
The oil temperature is raised to 65 degrees Celsius and the latent heat separates moisture and gases. The viscosity of the oil is reduced and enables filtration process. The pressure valve controls rise of pressure beyond specified limits.
The solid particles are removed partially through the filter medium which has multi stages with coarse and fine filters. The sludge and dirt are removed by two ways namely filter candles and centrifugal action.
Cartridges of one micron size filters hold huge amounts of dust, which could be disposed easily. The draining of filtered oil is supported with appropriate aeration facilities. These strainers can be cleaned without dismantling the filter from the pipeline.
The filter candles may be edge filters or depth filters. Advancement is technology has replaced edge type paper filters with filter cartridges. Centrifugal action however replaces recurring costs of replacing filters.
Media contact
Company Name: Hering VPT
Contact Person: Detlev Bastek
Email: Send Email
Phone: +49 9831 8834666
Address: D-91550 Dinkelsbuhl,Ernst-Schenk-Str.10
Country: Germany
Website: http://www.hering-vpt.com/