Product introduction:

Buried transformers, also known as underground transformers, domestically call this compact substation equipment that places transformers, high-voltage load switches, fuses, etc. in dry oil tanks as underground combined transformers. It is installed in a pit, does not occupy surface space, and can be submerged in water for a period of time. It is suitable for urban distribution networks such as urban residential quarters, industrial parks, and urban traffic arterial roads. The use of underground transformers can save the area of urban power distribution facilities and improve the utilization rate of urban land.

The pre-installed underground box transformer is our company’s concept of advocating green power, optimizing the urban environment, learning advanced foreign technology, incorporating modern urban ecological design concepts, and gradually burying the transformer underground for installation.

The company uses advanced technology to carefully create a new generation of underground power distribution equipment, a pre-installed underground box change. This product is composed of underground combined transformer, outdoor low-voltage cabinet, light box type low voltage protective shell and prefabricated underground combined transformer base. It is a complete set of underground power distribution equipment pre-assembled in the factory. Light box type cable branches can also be added according to user needs. Box and light box type high voltage metering provides a perfect solution for 10kV power distribution. The provided pre-installed underground boxes are transformed into urban power grids and provide new and reliable technical equipment for the transformation of urban power grids. In the environmental constraints, favorable conditions for power grid transformation in areas where land and housing are tight. It is mainly used to replace traditional civil construction forms of substations, European-style box-type substations, and American-style box-type substations to realize new power products with substation and power distribution functions.

Model and meaning

Features 

•The underground box substation has the characteristics of corrosion resistance, waterproof, low temperature rise, low noise, easy installation, and maintenance-free; it is a typical energy-saving product.
•The fuel tank is made of low-alloy structural steel, and its comprehensive mechanical properties, welding performance and low-temperature toughness are all very good. The tank body adopts hot-spray zinc technology and supplemented by plastic spraying, which has strong corrosion resistance.
•Using a fully sealed structure, the exposed parts of the high and low voltage terminals are isolated from the environment by imported sealing and waterproof materials. When the local buried transformer is installed, it is placed in a pit. When the local pit is flooded or even submerged, the buried transformer can still operate safely, can resist flood disasters, and can effectively improve the reliability of the power supply system.
•Using a unique heat sink structure to ensure the heat dissipation capacity and rust resistance of the heat sink.
• The protective shell of the low-voltage cabinet adopts a patented outdoor light box-type protective shell, and both sides of the light box-type outer wall can be installed with all-weather advertising boards, using small, green and energy-saving LED light-emitting components.
•The foundation of the underground transformer is a pre-assembled structure, which can be prefabricated with different materials flexibly according to customer requirements.

Technical Parameters

Underground combined transformer appearance structure low-voltage side

The low-voltage cable of the underground combined transformer is generally led to the low-voltage distribution box installed on the ground nearby as shown in the figure below. Low-voltage circuit breakers, fuses, meters and other electrical equipment required by users of low-voltage junction boxes.

① ① Low voltage terminal②Low voltage cable③Low voltage outlet box

Schematic diagram of underground combined transformer

1. Two-position load switch
2. Plug-in fuse
3. High-voltage casing
4. Hanging
5. Non-excitation tap changer
6. Low pressure casing
7. Pressure relief valve
8. Temperature and oil level gauge
9. Grounding terminal
10. Oil filling plug

Schematic diagram of underground combined transformer

Ring type

Terminal type