Types And Characteristics Of Power Transformers

The classification of commonly used power transformers can be summarized as follows:
1. Divide according to phase number:
(1) Single-phase power transformer: used for single-phase loads and three-phase power transformer sets.
(2) Three-phase power transformer: used to increase and decrease voltage in three-phase systems.
2. According to cooling method:
(1) Dry-type power transformer: relies on air convection for cooling, and is generally used for small-capacity power transformers such as local lighting and electronic circuits.
(2) Oil-immersed power transformer: relies on oil as the cooling medium, such as oil-immersed self-cooling, oil-immersed air cooling, oil-immersed water cooling, forced oil circulation, etc.
3. According to usage:
(1) Power transformer: used to increase and decrease voltage in power transmission and distribution systems.
(2) Instrument transformers: such as voltage transformers, current transformers, used in measuring instruments and relay protection devices.
(3) Test transformer: It can generate high voltage and conduct high-voltage tests on electrical equipment.
(4) Special transformers: such as electric furnace transformers, rectifier transformers, adjusting transformers, 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 regional substations of power systems to connect three voltage levels.
(3) Autotransformer: used to connect power systems with different voltages. It can also be used as an ordinary step-up or step-down transformer.
5. According to the core form:
(1) Core transformer: power transformer used for high voltage.
(2) Amorphous alloy transformer: Amorphous alloy iron core transformer is made of new magnetic conductive materials, and the no-load current is reduced by about 80%. It is a distribution transformer with ideal energy-saving effect. It is especially suitable for loads in rural power grids and developing areas. places with lower rates.
(3) Shell type transformer: special transformer for large current, such as electric furnace transformer, welding transformer; or power transformer for electronic instruments, TV, radio, etc.