The purpose of the utility model is to provide a 3150KVA amorphous alloy dry-type transformer, which not only retains the advantages of moisture-proof, dust-proof, anti-fouling of Nomex paper-encapsulated type, compact structure, small size, but also has the advantages of good heat dissipation of open type.

The utility model discloses a dry-type transformer comprises an iron core, a cylindrical inner coil, a cylindrical outer coil, an insulating cylinder between the inner and outer coils, and is characterized in that: an axial ventilation air duct is arranged inside the inner coil or inside the outer coil. It is good that there is an axial ventilation duct inside the inner coil and inside the outer coil. The above-mentioned structural characteristics have greatly improved the heat dissipation conditions of dry-type transformers.
On the basis of the above-mentioned structure, in order to further improve the heat dissipation performance of the dry-type transformer of the utility model, the product is good and also has one or several of the following structural characteristics simultaneously:
an axial ventilation air duct is arranged between the insulating cylinder and the outer coil;
An axial ventilation duct is arranged between the insulating cylinder and the inner coil;
An axial ventilation duct is arranged between the inner coil and the core;
The outer coil is a segmented cylindrical type split along the axial direction, and a radial (i.e., horizontal) ventilation duct is provided between the outer coils of each section of the cylindrical type.
The utility model discloses an advantage: due to the existence of various ventilation air ducts, the heat dissipation capacity of dry-type transformer is enhanced. The utility model has the advantages of good electrical performance, high mechanical strength, low noise, good fire resistance, strong ability to adapt to the environment, strong ability to withstand thermal shock, small size, and has good heat dissipation, and overload capacity has been further improved.Background technology: At present, there are two kinds of dry-type transformers with H-class insulation, one is H-class insulation impregnated type, its coil is made of glass wire wrapped wire or Nomex paper wrapped wire, wound into a pie coil, after impregnating with insulating paint, the coil is not encapsulated, so it is also called open type. The big advantage of this transformer is that each turn is in contact with the cooling air, and the heat dissipation is very good, but the big disadvantage is that it is easy to deposit dust on the horizontal surface of the wire cake of the coil, and if the impregnated paint moisture resistance is not good, the transformer is easy to get wet, the anti-pollution ability is poor, and the volume is larger than that of the cylindrical coil.

The other is paper-encapsulated type, its coil is made of H-grade enameled wire or Nomex paper-wrapped wire, copper foil winding for layer coil, coil conductor and winding upper and lower ends are made of Nomex paper and insulating glue, after special process treatment, encapsulation and curing and air isolation. This kind of transformer has a very strong ability to prevent moisture, dust and pollution, and has a compact structure and small size, but the heat dissipation is not as good as that of the open type.