What is the role of the oil in the transformer?
Jul 29, 2020
Transformers are usually divided into dry-type transformers and oil-immersed transformers. Only oil-immersed transformers need to be filled with transformer oil. In oil-immersed transformers, the role of transformer oil is insulation and heat dissipation.
The main function of transformer oil:
(1) Insulation: Transformer oil has much higher insulation strength than air. The insulating material is immersed in oil, which not only improves the insulation strength, but also protects it from moisture.
(2) Heat dissipation: Transformer oil has a large specific heat and is often used as a coolant. The heat generated during the operation of the transformer causes the oil close to the iron core and windings to expand due to heat. Through the upper and lower convection of the oil, the heat is dissipated through the radiator to ensure the normal operation of the transformer.
(3) Arc suppression effect: On the oil circuit breaker and the on-load voltage regulating switch of the transformer, an arc will be generated when the contacts are switched. Because the transformer oil has good thermal conductivity, and can separate a large amount of gas under the high temperature of the arc, and generate a large pressure, the arc extinguishing performance of the medium is improved, and the arc is quickly extinguished.
