Advantages and disadvantages of oil immersed transformers

Oil immersed transformer refers to a transformer whose winding uses insulating oil as the insulating medium. Due to the much higher electrical and mechanical strength of oil compared to air, as well as its excellent insulation performance, the cooling method for oil immersed transformers can be natural cooling, forced air cooling, or forced air cooling. The windings of oil immersed transformers use impregnated insulating oil as the insulation medium, which can save a lot of energy. Therefore, it is widely used in power systems. Compared with dry-type transformers, oil immersed transformers have the following advantages:

1. The winding uses insulating oil as the insulation medium, which can effectively reduce the weight of the transformer.

2. Oil immersed transformers have good heat dissipation effects, which can reduce faults caused by poor heat dissipation during operation.

3. Oil immersed transformers have good moisture-proof performance.

1. Purpose

1. Oil immersed transformers are used as main transformers in high-voltage power systems. This transformer is generally used in various large and medium-sized power plants, substations, and industrial and mining enterprises.

2. The main purpose of oil immersed transformers is to provide electrical energy to load equipment as the main power source, meet the requirements of various voltage levels of electrical equipment, and meet the requirements of large capacity power system operation; As a basic electrical component, it is widely used in industrial and mining enterprises, national key construction projects, and large-scale engineering projects, such as nuclear power plants, thermal power plants, large hydropower stations, and railway electrification; As a basic electrical component, it is widely used in various small capacity electrical equipment and household appliances, such as televisions, refrigerators, air conditioners, washing machines, etc; As a fundamental electrical component, it is widely used in various computers, peripherals, and other electrical appliances.

3. Oil immersed transformers are one of the important equipment in power systems. With the development of social economy and science and technology, especially the application of computer technology and digital technology in the power system, oil immersed transformers will be further developed.

2. Technical parameters

(1) Rated capacity: refers to the rated voltage that a transformer can withstand during normal operation.

For rectifier transformers, in order to ensure that the voltage is raised to the rated value within the specified time, the voltage must be raised to the highest value during no-load operation; For inverter transformers, due to certain losses during the inverter process, the amplitude of voltage rise is limited, and the voltage must be increased to the rated value.

(3) No load current: refers to the current flowing through a transformer during no-load operation, which is the basis for calculating no-load losses. If the no-load current is too high, it will cause local overheating of the transformer and even burn out the winding.

(4) Short circuit current: refers to the current flowing through a transformer during a short circuit, and its value can be calculated by the electric force generated in the winding.

(5) Allowable continuous working time: refers to the maximum load that a transformer can withstand for one hour of continuous operation under a specified load. For inverter transformers and rectifier transformers, due to certain losses during the inverter process, the continuous working time generally does not exceed 15 minutes.