Types and characteristics of power transformers

The power transformer is divided according to the number of phases

(1) Single-phase power transformer; used for single-phase load and three-phase power transformer group.

(2) Three-phase power transformer; used for step-down voltage of three-phase system

2. The power transformer is divided according to the cooling method

(1) Dry-type power transformer: rely on air convection for cooling, generally used for local lighting, electronic circuits and other small-capacity power transformers

(2) Oil-immersed power transformer: rely on oil for cooling properties, such as oil-immersed self-cooling, oil-immersed air-cooled, oil-immersed water-cooled, forced oil circulation, etc.

3. Power transformers are divided by use

(1) Power transformer: used for raising and lowering voltage of power transmission and distribution system

(2) Instrument transformers: such as voltage transformers, current transformers, used for measuring instruments and relay protection devices.

(3) Test transformer: It can generate high voltage and conduct high voltage test on electrical equipment.

(4) Special transformers: such as electric furnace transformers, rectifier transformers, adjustment transformers, etc.

4. The power transformer is divided according to the winding form:

(1) Double-winding transformer: used to connect two voltage levels in the power system

(2) Three-winding transformers are generally used to connect and learn full voltage levels in power stations in power system areas.

(3) Autotransformer: used to connect power systems of different voltages. It can also be used as a back-through step-up or step-down transformer.

5. The power transformer is divided according to the form of iron core

(1) Core transformer; power transformer for high voltage

(2) Amorphous alloy transformer: Amorphous alloy core transformer is a new type of magnetically conductive material, and the no-load current drops by about 80%. It is a distribution transformer with an ideal energy-saving effect and is especially suitable for rural power grids and developing areas. lower place.

(3) Shell-type transformers: special transformers for large currents, such as electric furnace transformers, welding transformers; or power transformers for electronic instruments, TVs, radios, etc.