We know that oil-immersed transformers all have temperature, the application of oil-immersed transformers is indispensable for oil-immersed transformer oil, oil-immersed transformer oil has temperature, and the temperature of many oil-immersed transformer oils They all reflect the overall operation of the oil-immersed transformer, and maintain the continuous development and improvement of the role of the oil-immersed transformer. Generally speaking, the temperature of oil-immersed transformer oil can be measured accurately, so how to measure the temperature of oil-immersed transformer accurately?

Oil-immersed transformer temperature resistance:

Oil-immersed transformer temperature is limited by the high temperature resistance of insulating materials. The temperature resistance performance of transformers is different. The insulating layer of high voltage electrical equipment can be divided into seven high temperature resistance levels: Y, a, E, B, F, H, and C. Different types of insulating materials have different high temperature resistance capabilities. For example, the high temperature resistance of Class A insulating materials is 105 °C, while the high temperature resistance of Class B insulating materials such as biotite, laminated glass, and asbestos is 130 °C. The high temperature resistance of Class F insulating materials is 155°C, and that of Class C insulating materials is over 180°C. Generally, the flame retardant grades of oil-transformed oil-immersed transformers belong to grade a. That is, the temperature of the larger network hot spot of the electromagnetic coil cannot exceed 105°C, and the average temperature of the winding is 10°C higher than the oil temperature, and the oil temperature of the top layer of the oil-immersed transformer is higher than the oil temperature of the middle and lower layers. Therefore, monitoring the top oil temperature does not exceed 95 °C, which is actually equal to monitoring the electromagnetic coil temperature not exceeding 105 °C.

Oil-immersed transformer heat pipe cooling method:

Considering the avoidance of excessive oil deterioration, the higher the oil temperature, the faster the air oxidation rate of the oil, that is, the faster the oil embrittlement. Experiments confirmed that when the oil temperature increased by 10 °C, the air oxidation rate of the oil doubled. Therefore, the top oil temperature requires two standard values, normal and larger. For the strong oil air-cooled and guided air-cooled oil-immersed transformers, due to the improvement of the cooling method, the submersible gasoline pump is used to send the oil into the oil passage in the middle of the winding, which improves the actual effect of cooling and reduces the network hot spot temperature of the electromagnetic coil. , but because the fluidity of the oil becomes faster, the error of the average temperature between the top oil temperature and the winding is higher than that without the oil circulation system. Therefore, the control value of the top oil temperature is higher than that of the oil in the oil immersion overtemperature protection or air cooling method. Immersion transformer low.