There are two types of transformers: dry-type transformers and oil immersed transformers. Even though they have the same objective, these transformers differ significantly.This article will focus on the differences between dry-type transformers and oil-immersed transformers to compare which one is better.
1.Structural features
A dry type transformer is a power transformer whose windings and core are not immersed in insulating oil, but are insulated and cooled by air or other insulating media. This type of transformer is mainly made of dry solid insulating materials, usually including epoxy resin, glass fiber, etc. Since there is no liquid insulating medium, it is called a dry-type transformer.
An oil-immersed transformer is a transformer that uses insulating oil as a medium. Its main function is to reduce high-voltage electrical energy to applicable low voltage electrical energy to meet the power requirements of different equipment. Insulating oil plays a cooling and insulating role in oil-immersed transformers to ensure the normal operation of the transformer.
2.Environmental friendliness
Dry type transformers are generally superior in terms of environmental friendliness. Since no insulating oil is used, no liquid waste is generated and no liquid leakage occurs. In addition, the insulation materials of dry-type transformers are generally more environmentally friendly, such as the use of solid insulation materials such as epoxy resin.
Oil immersed transformers use insulating oil as an insulating medium and cooling medium, and insulating oil may contain harmful substances such as polychlorinated biphenyls (PCBs), which may cause environmental pollution if not handled properly. In addition, due to the presence of liquid oil, oil-immersed transformers also have safety risks during transportation and handling.
3.Performance characteristics
The main advantages of oil-immersed transformers are:
High reliability;
Good insulation performance;
Good cooling effect;
Strong overload capacity;
Relatively low maintenance cost;
However, oil-immersed transformers also have some disadvantages, such as oil seepage, oil leakage and other problems that may occur during long-term operation, which not only affects the working efficiency of the equipment, but also may pollute the environment and even cause safety problems such as fire. In addition, the internal structure of the oil-immersed transformer is relatively complex, and the technical level of the maintenance personnel is required to be high.
The main advantages of dry-type transformers are:
Strong fire resistance;
Environmentally friendly and pollution-free;
High mechanical strength;
Flexible installation;
Temperature monitoring and protection;
However, dry-type transformers also have some limitations, such as high manufacturing costs, which to a certain extent limits their application in some low-cost projects. At the same time, dry-type transformers can generally only be installed indoors. Their ability to resist harsh environments is relatively poor, and their adaptability to extreme environments such as high humidity and high temperature is limited. In addition, the leakage reactance of dry-type transformers is large, and the winding temperature rise may also be high, affecting the insulation performance.
4.Application scenarios
Dry-type transformers are suitable for applications that require high environmental safety and durability, such as indoor power distribution systems and high-rise buildings; while oil-immersed transformers are suitable for large power systems, especially in applications that require high power and high voltage, such as power transmission stations and factories. When choosing a transformer type, it is necessary to comprehensively consider the specific application requirements, environmental conditions, and safety requirements.
5.Maintenance
Dry-type transformers are simpler to maintain than oil-immersed transformers. They do not involve the management of insulating oil and the maintenance of the cooling system, but they still require regular inspection and maintenance of the state of the insulation material. Oil immersed transformers require more maintenance work, including the management of insulating oil, oil level monitoring, and the maintenance of the cooling system, but they can provide better cooling effects and insulation performance.
Oil-immersed transformers and dry type transformers each have their own advantages and disadvantages. The choice of which type of transformer should be based on a comprehensive consideration of multiple factors such as specific application scenarios, safety requirements, and operation and maintenance requirements. This can give full play to their strengths while minimizing the impact of their weaknesses.
