Distribution Transformer Construction

Distribution transformers are fundamental components in electrical power transmission systems, responsible for delivering lower voltages to end users, such as homes and businesses. In this article, we will discuss the construction of distribution transformers and the materials commonly used in their manufacturing.
Distribution transformers are built with two basic components: the core and the windings. The core is a stack of thin laminations made from electrical-grade steel, which reduces eddy currents and energy losses. The core is assembled in the shape of a rectangle, with the windings inserted in the center. The primary and secondary windings are wrapped around the core in layers with insulating material in between. These windings are made from copper or aluminum, depending on the specific application and cost considerations.
The primary winding is connected to the transmission network at high voltage, while the secondary winding provides power at low voltage to homes and businesses. The insulation of the transformer is essential to prevent electrical arcing and maintain safe operation. Insulation provides electrical resistance and physical barriers between the windings and the transformer's body, controlling the distribution of electrical energy.
Transformer oil, or insulating oil, is used to improve the insulation properties of the transformer. The oil also helps to cool the transformer, absorbing the heat generated in the core and windings, which can damage the transformer over time. The oil is typically added to the transformer during the manufacturing process.
The transformer is usually transported as a sealed unit and installed on a concrete pad. The electrical connections are made through bushings with insulating material, connecting the high voltage primary to the incoming transmission lines, and the low voltage secondary to the outgoing distribution lines. The transformer is then energized, and the electrical performance is tested to ensure that it meets the required specifications.
Finally, it is essential to maintain distribution transformers regularly, to ensure their safe and efficient operation. Routine maintenance includes oil level checks, cleaning bushings, and repair or replacement of damaged components.
In conclusion, the construction of distribution transformers is a critical process that combines electrical, mechanical, and material engineering. The materials used in the manufacturing, such as electrical-grade steel, copper or aluminum windings, and insulating oil, are carefully selected to ensure the transformer's proper operation and longevity. The safe and efficient operation of distribution transformers is essential to maintaining reliable electrical power delivery for homes and businesses.