A transformer is composed of several key elements: a core, windings, insulation, bushings, a tap changer, terminals, and a tank

 A transformer is composed of several key elements: a core, windings, insulation, bushings, a tap changer, terminals, and a tank. The core, typically made of silicon steel laminations, provides a magnetic path for the energy transfer. Windings, usually copper or aluminum, are wrapped around the core and are electrically isolated but magnetically linked. Insulation protects the windings and core from each other and from external elements. Bushings connect the windings to external circuits, and a tap changer regulates output voltage. 

Core: The core's primary function is to provide a path for magnetic flux. It's usually made of laminated silicon steel to minimize eddy current losses. 

Windings: These are coils of wire (typically copper or aluminum) that carry the electrical current. The primary winding is connected to the input voltage, and the secondary winding is connected to the output. The number of turns in each winding determines the voltage transformation ratio. 

Insulation: Various insulating materials are used to prevent short circuits between the windings and the core, as well as between different parts of the windings. Common insulating materials include oil and cellulose (paper/pressboard), according to Corefficient. 

Bushings: Bushings are insulated terminals that allow the high-voltage and low-voltage windings to be connected to external circuits while providing insulation from the transformer tank. 

Tap Changer: This component allows for adjustments to the output voltage by changing the number of active turns in the winding. 

Terminals: These are the points where the windings are connected to the external circuit. 

Tank: The tank houses the core, windings, and other internal components and provides structural support and protection from the environment. It may also contain cooling systems. 

Other important components include:

Cooling Tubes:

Used in larger transformers to dissipate heat generated by the transformer's operation. 

Buchholz Relay:

Detects faults within the transformer and monitors the oil level, according to a YouTube video. 

Desiccant Dryer (Silica Gel Breather):

Absorbs moisture from the air to prevent water ingress and potential damage to the transformer's insulation.