What is a prefabricated substation?

Prefabricated substation: It is a complete set of equipment pre-installed and type tested, usually composed of high-voltage power distribution equipment, transformers, and low-voltage power distribution equipment, and combined in one or several cabinets. Also called "box-type substation".

Box-type substations are suitable for residential quarters, urban public transformers, bustling downtowns, construction power supplies, etc. Users can choose box-type transformers according to different usage conditions and load levels.

The box-type transformer substation shell is made of steel plate or alloy plate, equipped with a double-layer top cover, and the box-type transformer has good heat insulation. The shell and frame are all anti-corrosion treatment, and American transformers have long-term outdoor use conditions. The shape and color can be coordinated with the environment. It is easy to install. A cable room is provided under the foundation of the box-type substation, and a manhole is provided in the low-voltage room to enter the cable room for work. In terms of volume, the European-style box substation has a larger product volume due to the internal installation of conventional switch cabinets and transformers. The American box substation has a small volume due to the integrated installation.

The high-voltage side of the box transformer is protected by load switches and current-limiting fuses. When a one-phase fuse is blown, use the striker of the fuse to open the load switch at the same time to avoid phase loss operation. The high-voltage power distribution cabinet and the low-voltage power distribution cabinet require the load switch to have the ability to cut off and transfer current. The low-voltage side adopts load switch and current-limiting fuse protection, the high-voltage side of American box substation adopts fuse protection, and the load switch only has the function of switching and cutting off the high-voltage load current, and the capacity is small. When one-phase fuse blown occurs on the high-voltage side, the voltage on the low-voltage side will decrease, and the under-voltage protection or over-current protection of the plastic case automatic air switch will be activated, and low-voltage operation will not occur. From the perspective of product cost, European-style boxes have become costly. From the perspective of product price reduction, there is still a large price reduction room for American box substations. On the one hand, the three-phase five-column iron core of American box substation can be changed to three-phase three-column iron core. On the other hand, the high-voltage part of American box substation can be modified from The transformer tank is moved out of the tank, occupying the space of the high-voltage room.