The distribution transformer is an important part of the power system, which is used to transform the power input from the high-voltage transmission line into low-voltage power suitable for users. It is a kind of BCM4318EKFBG Static transformer realizes the transformation of electric energy through the principle of electromagnetic induction. Distribution transformers are widely used in industry, agriculture, commerce, residential power and other fields.
1、 Basic structure
The distribution transformer is composed of iron core, coil and shell. The iron core is made of laminated silicon steel sheets, which is used to improve the permeability of the transformer and reduce the magnetic loss. The coil includes high-voltage coil and low-voltage coil, which are respectively wound on both sides of the iron core and isolated by insulating materials. The enclosure is used to protect the internal components of the transformer and has the functions of isolation, cooling and protection.
2、 Features
1. Small size and light weight: compared with the generation transformer, the power of the distribution transformer is smaller, and its size and weight are relatively small.
2. Reliable operation: the distribution transformer adopts closed core and winding structure, with high stability and reliable operation.
3. Energy saving and high efficiency: the iron loss and copper loss of distribution transformer are low, and the energy efficiency is high.
4. Convenient maintenance: the distribution transformer has simple structure, convenient maintenance and long service life.
3、 Operating principle
The working principle of distribution transformer is based on Faraday's law of electromagnetic induction, that is, when the current in one winding changes, the induced electromotive force will be generated in the other winding. When the AC current is connected to the winding on the HV side, the corresponding electromotive force will be generated in the winding on the LV side, thus realizing the transmission and conversion of electric energy.
4、 Classification
1. Classification by use: distribution transformers can be divided into power plant transformers, substation transformers, industrial transformers, rural transformers, urban transformers, special purpose transformers, etc.
2. Classification by cooling mode: distribution transformers can be divided into natural cooling transformers and forced cooling transformers.
3. According to the connection mode of transformers, distribution transformers can be divided into three-phase transformers and single-phase transformers.
4. Classification by structure: distribution transformers can be divided into oil immersed transformers and dry-type transformers.
5、 Supply mode
There are two power supply and distribution modes for distribution transformers, namely, single-phase power supply and three-phase power supply.
1. Single phase power supply and distribution: applicable to some small power power systems, mainly used in residential areas, commercial buildings and other places.
2. Three phase power supply and distribution: applicable to high-power power system, mainly used for distribution network of industrial and mining enterprises and power system.
6、 Operation and maintenance
In order to ensure the normal operation of the distribution transformer, certain operation and maintenance work should be carried out. Common maintenance work includes the following aspects:
1. Clean insulating oil: filter and replace the insulating oil regularly to keep the cleanliness of insulating oil.
2. Check the insulation condition: regularly check the insulation condition of winding and iron core, and timely deal with problems found.
3. Check the wiring: regularly check the wiring of the transformer to ensure good wiring.
4. Check the cooling system: regularly check the working condition of the cooling system to ensure good cooling effect.
5. Check the mechanical parts: regularly check the mechanical parts of the transformer, such as connecting bolts, grounding devices, etc., to ensure that they are intact.
7、 Common fault analysis
Common faults include the following:
1. Insulation damage: the insulation material of the transformer may be damaged due to aging, moisture or external force, leading to the decline of insulation performance or even failure. This will cause insulation breakdown of the transformer, which may cause fire in serious cases.
2. Poor contact of copper wire: the connection of copper wire inside the transformer may be loose, oxidized or corroded, resulting in poor contact, which may lead to the rise of line resistance, heating or even short circuit fault.
3. Cooling system failure: the cooling system of the transformer includes cooling oil and radiator. If the cooling oil leaks, the circulating system is blocked or the radiator is dirty and blocked, the transformer may overheat, or even cause a fire.
4. Overload or short circuit: Overload means that the load carried by the transformer exceeds the rated capacity, and long-term overload will lead to overheating of the transformer winding, which will lead to failure. Short circuit refers to the direct contact between two or more windings of the transformer, resulting in a sharp increase in current and damage to the transformer.
5. External factors: such as lightning strike, power grid failure, power equipment failure and other external factors may also lead to the failure of distribution transformers.
8、 Development history
The development of distribution transformers can be traced back to the end of the 19th century, when people began to study and apply transformer technology due to the development needs of the power system. With the continuous development of the power system, distribution transformers have gradually become an indispensable part of the power system.
In the early days, distribution transformers were mainly oil immersed, in which insulating oil played the role of insulation and heat dissipation. With the progress of technology, oil immersed transformers have been widely used and become one of the most common types of transformers in the power system at that time.
With the increasing requirements of power system on transformer performance, people begin to develop new dry-type transformers. Compared with oil immersed transformers, dry-type transformers do not need insulating oil and have higher safety and reliability. Therefore, in some special occasions, dry-type transformers have gradually replaced oil immersed transformers.
In addition, with the continuous progress of science and technology, people began to research and apply new materials and technologies, such as the improvement of insulation materials, the application of temperature sensors, etc., which further improved the performance and reliability of distribution transformers.
In general, distribution transformers are constantly developing and improving to meet the needs of the power system. In the future, with the increasing demand of power system for energy, distribution transformers will continue to develop to provide more efficient and reliable power conversion services.
