Single phase pad mounted power transformer is key equipment for voltage conversion in distribution networks and are widely used in outdoor low-voltage distribution scenarios. Its core function is to convert medium-voltage alternating current into low-voltage power to provide electricity for residential, commercial or small industrial users.
Introduction:
Single phase pad mounted power transformer is a single-phase designed, outdoor-installed sealed power transformer that operates by being fixed on a ground base. It is specifically designed for single-phase loads, distinct from three-phase transformers and also different from pole-mounted or underground transformers.
Core structure composition:
Iron core
Material: High-permeability silicon steel sheets, with hysteresis loss and eddy current loss reduced through lamination process.
Function: To form a magnetic circuit and transmit the magnetic field required for electromagnetic induction.
Winding
Material: Usually high-purity copper wire, with insulating paper or film wrapped on the surface.
Structure: It is divided into primary winding and secondary winding. The turns ratio of the winding determines the voltage conversion ratio.
Fuel tank and insulation cooling system
Fuel tank: Sealed steel shell, filled with insulating oil inside, it has both insulation and heat dissipation functions.
Cooling method: Mostly oil-immersed self-cooling, heat is transferred to the tank wall through the natural convection of the oil, and then dissipated through the casing. Some large-capacity models will add heat sinks to enhance heat dissipation.
Protective device
Pressure relief valve: When the internal pressure suddenly rises due to a fault, it automatically releases the pressure to prevent the fuel tank from exploding.
Temperature controller: Monitors the oil temperature and triggers an alarm when it exceeds the threshold.
Desiccant: Adsorbs moisture in the air to prevent insulating oil from getting damp and deteriorating.
Grounding device: The casing is forcibly grounded to avoid the risk of leakage.
Terminal blocks and housing
High-voltage side: Connect the medium-voltage cable through an insulating sleeve.
Low-voltage side: Connect the low-voltage distribution cabinet through copper bars or cables.
Shell: Made of corrosion-resistant steel, it has the functions of rainproof, dustproof and anti-vandalism, and the surface is usually coated with a sun protection layer.
Advantages:
Strong outdoor adaptability: With a sealed casing and insulating oil design, it can operate for a long time in rainy, snowy, high-temperature and sandy environments.
Easy installation: It can be directly fixed on the concrete base without the need to build a machine room and occupies a small area.
Low maintenance cost: The sealed structure design can effectively prevent insulating oil from being contaminated and deteriorating. Daily maintenance only requires checking whether the oil level is too low, whether the temperature is normal and whether the casing is intact.
Super safety: The grounding design and the provision of protective devices significantly reduce safety risks.