What safety components exist in an oil immersed transformer?

As an important power conversion device in the power system, the stable operation of the oil-immersed transformer is crucial to ensure the safety and reliability of the power system. In order to ensure the safe operation of the oil-immersed transformer under various working conditions, a variety of safety components are designed. These safety components perform their respective functions and together constitute the safety protection system of the oil-immersed transformer.

1.Oil tank

As the basic component of oil-immersed transformers, the oil tank is used to contain transformer oil and cool the core and windings, ensure the tightness of the transformer, and prevent oil leakage.

2.Oil conservator

The oil conservator is cleverly installed on the oil tank, effectively isolating the inside of the oil tank from the outside air. Its design is like a horizontally rotating cylinder, aiming to reduce the contact area between the transformer oil and the air. At the same time, it is also equipped with an oil level gauge to facilitate the observation of the oil level. In addition, in order to prevent moisture intrusion and facilitate regular sampling tests, the oil conservator and oil tank are also equipped with equipment such as desiccant and oil drain valve.

3. ‌Safety airway‌:

The safety airway is an important protective device on the top cover of the oil tank, which is a long round steel cylinder. When a transformer fails and a large amount of gas is generated, it can prevent the oil tank from bursting and ensure safety. In recent years, domestic power transformers have gradually adopted pressure relief valves to replace traditional explosion-proof pipes to achieve higher action accuracy and shorter delay time.

4. Gas relay: Gas relay, also known as float relay, is connected to the safety gas duct and is used to monitor and judge the internal fault of the transformer. When the gas generated by the fault in the transformer reaches a certain level, the circuit is turned on to alarm; when the oil level drops sharply due to serious oil leakage, the circuit is quickly cut off; when a sudden fault occurs in the transformer and the oil flows to the oil pillow, the circuit is quickly cut off.

5.Oil purifier: 

The transformer oil purifier uses the temperature difference between the upper and lower oil temperatures to circulate the oil in the oil purifier. During this process, the silica gel in the oil purifier absorbs harmful substances in the oil such as moisture, free carbon and oxides, thereby purifying the transformer oil and maintaining its good electrical and chemical properties. 

6.Temperature measuring device: 

The temperature measuring device is mainly used to monitor the oil surface temperature of the transformer. For small oil-immersed transformers, mercury thermometers are usually used for measurement; for large oil-immersed transformers, pressure thermometers may be used. These temperature measuring devices can reflect the operating status of the transformer in real time, providing an important basis for operation and maintenance.

The safety components of oil-immersed transformers each have their own functions and together constitute the transformer's safety protection system. The design and manufacture of these components are subject to strict standards and tests to ensure the stable operation and safety performance of the transformer. During use, regular inspection and maintenance are equally important, which can timely discover and deal with potential safety hazards and ensure the stable operation of the power system.