The American box-type transformer is a unified design of transformers, load switches, protective fuses and other equipment. The windings and cores of the transformer, high-voltage load switches and protective fuses are all in the same oil-filled box. There is no relatively independent high and low voltage. Switchgear. The box body is a fully sealed structure, using concealed high-strength bolts and silica gel to seal the box cover; the low-pressure chamber is independently set outside the fuel tank. The American box-type transformer is divided into two parts: front and rear. The front is the high and low voltage operating intervals. The operating intervals include high and low voltage bushings, load switches, off-load voltage regulating tap-changers, plug-in fuses, and pressure relief valves. , thermometer, oil level gauge, oil filling hole, oil drain valve, etc.; the rear is the box and heat sink.
European box-type substation (prefabricated substation) is a device that places high-voltage switchgear, distribution transformers and low-voltage distribution devices in three different compartments and realizes electrical connections through cables or busbars. The high and low voltage switch cabinets are relatively independent and compact and are pre-installed with the transformer in a box that can be hoisted and transported. The transformer room, high voltage room and low voltage room are all equipped with independent doors, so its volume is larger than that of the American box type.
The underground transformer is a compact combined power distribution facility in which the transformer, high-voltage load switch and protection fuse are installed in the oil tank. It is placed in the pit during installation. It does not occupy space, can be immersed in water for a certain period of time, and is maintenance-free. It is conducive to saving the area occupied by urban power distribution facilities, so it has broad application prospects in urban network transformation and construction.
