Oil-Immersed Distribution Transformers: Working Principle and Maintenance

2023-09-12

The Working Principle of Oil-Immersed Distribution Transformers

Oil-immersed distribution transformers consist of the following main components:

Core: The core is made up of stacked silicon steel sheets, forming a magnetic circuit.
Windings: Windings are made of copper wire and are wound around the core. The high-voltage winding is on the outer side, while the low-voltage winding is on the inner side.
Oil Tank: The oil tank surrounds the windings and core, providing cooling and insulation.
The working principle of oil-immersed distribution transformers is as follows:

High-voltage current flows through the high-voltage winding, creating a magnetic field in the core.

The magnetic field passes through the low-voltage winding, inducing current in the low-voltage winding.

Low-voltage current is then supplied from the low-voltage winding.

Advantages and Disadvantages of Oil-Immersed Distribution Transformers

Oil-immersed distribution transformers have the following advantages:

High Efficiency: Oil-immersed distribution transformers typically operate at an efficiency of 90% or higher.

Long Service Life: These transformers generally have a service life of 20 years or more.

Reliable Operation: Oil-immersed distribution transformers exhibit good resistance to interference and can operate in various environmental conditions.

However, they also come with certain disadvantages:

Large Size: These transformers are usually quite bulky in terms of size.

Heavy Weight: Oil-immersed distribution transformers tend to be heavy due to their construction.

High Maintenance Costs: Regular maintenance is required for these transformers to ensure their proper functioning.

How to Choose an Oil-Immersed Distribution Transformer

When selecting an oil-immersed distribution transformer, several factors need to be considered:

Capacity: The transformer’s capacity should meet the load requirements.

Voltage Rating: The voltage rating of the transformer should match the voltage level of the electrical grid.

Installation Method: The installation method of the transformer should be compatible with the site conditions.

Maintenance of Oil-Immersed Distribution Transformers

Regular maintenance is essential for oil-immersed distribution transformers to ensure their longevity and reliable performance. Maintenance tasks include:

Oil Level Check: The oil level should be maintained within the designated range on the oil tank.

Oil Quality Check: The oil should be clear and free from impurities.

Insulation Testing: Insulation testing should meet relevant standards and requirements.

In summary, oil-immersed distribution transformers are vital components of electrical distribution systems, and their proper selection and maintenance are critical for ensuring a reliable and efficient power supply.