Three-phase oil-immersed transformers have a voltage regulation range function with an oil reservoir.

A brief introduction to its key features:
Three-phase design and oil-cooled: Adopting a three-phase winding structure, it meets the transmission requirements of three-phase alternating current power systems; the core and windings are immersed in insulating transformer oil, using the convective circulation of the oil to transfer heat to the oil tank wall or radiator, ensuring the heat dissipation efficiency of the equipment under high load.
Voltage regulation function: Through the tap changer (on-load or off-load tap changers), voltage regulation is achieved, allowing the tap to be switched within a certain range of the rated voltage (usually ±5% or ±2.5%) to compensate for the voltage fluctuations in the power grid and ensure stable output voltage, meeting the voltage requirements of different loads.
Function of the oil reservoir: As an accessory device of the oil tank, the oil reservoir stores a certain amount of transformer oil to balance the volume expansion of the oil due to temperature changes, avoiding abnormal pressure in the oil tank; at the same time, it reduces direct contact between the oil and air, delays oil oxidation and moisture absorption, and cooperates with the desiccator to further protect the oil quality and extend the service life of the transformer.
This type of transformer combines the compatibility of three-phase power supply, the reliability of oil-cooled cooling, the flexibility of voltage regulation, and the protection function of the oil reservoir. It is widely used in medium and high-voltage power transmission and distribution networks and is a key equipment for ensuring the stable operation of the power system.