Types of Oils Used
Mineral oil and Synthetic oil are the majorly used transformer oil.
Mineral Oils
These are petroleum products, like Naphthenic-based transformer oil and Paraffinic-based transformer oil. Naphthenic-based transformer oils are known for their heat distribution, which is one of the main problems with transformers. This also has a good flowing feature and is wax-free under low temperatures. These types of oils are better for low-temperature. Even though it oxidizes easier, the product formed by this process (i.e., sludge) is soluble. Hence, it won’t obstruct the cooling system of the transformer.
Paraffinic-based transformer oil is obtained from paraffinic crude oil using solvent separation methods. This is known for its good thermal and oxidation durability and good high-temperature viscosity feature. Because of its high viscosity index due to the presence of wax, though the oxidation rate is lower than the naphthenic oils, the precipitant or the sludge is formed due to the oxidation. This might become an obstruction for heat dissipation. Since the rate of oxidation is low, cost-effective, and available, this oil is widely used in India.
Synthetic Oils
Synthetic oils which are generally silicone based were popular in the middle of the 70s. This is generally used in fire-prone areas because of its fire-retardant properties. It also has a few problems with low heat dissipation and high moisture-absorbing capacity. It is also costlier than mineral oil.
Mineral oil is hazardous directly for humans and the environment. This is mostly available as the by-product of refining crude oil to make gasoline and other petroleum products. This mainly consists of alkanes and cycloalkanes. And its poor biodegradability makes it potential long-term pollution for the environment. And also these are classified under carcinogenic substances by the World Health Organization.
Some of the advantages, when compared to mineral oil, are:
*Low volatility
*High fire point, so that it can be used in high-fire-risk places
*Lower pour point
*Greater moisture tolerance
*Improved function at high temperatures
*Non-toxic
*Bio-degradable.
Silicone-based oils are even less flammable but they are not only more expensive than esters but also less bio-degradable. Research is going on in the usage of vegetable-based oils like coconut oil. But it is found unsuitable for the cold climatic condition and also for voltages over 230kV. one can also say that the dissipation factor is reducing over the period which is not as usual as in the case of other transformer oils.
#trending #transformers #transformeroil #educational #educationalvideo #engineering #electrical #eee #typesof transformeroil #typeof transformeroil test #mostviralvideo
