The classification of commonly used transformers can be summarized as follows.
1, according to the number of points:
1) single phase transformer: used for single-phase load and three-phase transformer set.
2) three-phase transformer: used in three-phase system up and down voltage.
2, according to cooling way points:
1) dry-type transformers: rely on air convection for natural cooling or increase fan cooling, more used in high-rise buildings, high-speed toll stations, electricity and local lighting, electronic circuits and other small capacity transformers.
2) oil immersed transformers: rely on oil as cooling medium, such as oil immersion, self cooling, oil immersed air cooling, oil immersed water cooling, forced oil cycle, etc..
3, according to the use of points:
1) power transformers: used in power transmission and distribution systems up and down voltage.
2) instrument transformers: such as voltage transformers, current transformers, measuring instruments and relay protection devices.
3) test transformer: can produce high voltage, electrical equipment for high voltage test.
4) special transformers: such as electric furnace transformer, rectifier transformer, adjustment transformer, capacitor transformer, phase-shifting transformer, etc..
4, according to winding form:
1) double winding transformer: used to connect two voltage levels in the power system.
2) three winding transformer: generally used in power system regional substation, connect three voltage levels.
3) autotransformer: a power system used to connect different voltages. The utility model can also be used as an ordinary step-up or down transformer.
5, according to the form of iron core:
1) core transformers: power transformers for high voltage applications.
2) amorphous alloy transformer: amorphous core transformers is a new magnetic material, the no-load current is decreased by about 80%, is the ideal transformer energy saving effect, especially suitable for rural and developing areas such as grid load rate low place.
3) shell Transformers: special transformers for large currents, such as electric furnaces, transformers, arc welding transformers, or power transformers for electronic instruments and television, radio, etc..