Influence Of Cast Resin HV Transformer Shell Temperature On Transformer
Components of cast resin hv transformers include valve body (iron core, winding, insulation, lead wire), cooling device, pressure regulator, transformer housing, protection device (hygroscopic device, safety gas circuit, gas relay, oil conservator and temperature measurement) device, etc.) and outlet casing.
Cast resin hv transformers have many casings during operation, and the casings are made of steel plate, aluminum alloy or stainless steel. How to dissipate the heat generated by the transformer during operation and ensure the normal operation of the transformer is an important indicator of the advantages and disadvantages of designing indoor substations. This is also an important factor that must be considered in transformer design.
There are many reasons that affect the temperature rise of cast resin hv transformers. In addition to the heat generated by the transformer itself, the size of the cooling air channel, the height of the main body, etc., it is also related to the degree of protection of the enclosure and the ambient temperature and airflow.
The parameters of the transformer itself and the size of the cooling air passage should be adapted to the structure.
The cooling capacity of the housing also plays a decisive role in the transformer temperature system. If the air inside and outside the casing is not well circulated, the heat inside the casing will build up more and more. After long-term operation, the ambient temperature inside the casing will become higher and higher. The higher the temperature rise of the transformer and the higher the ambient temperature, the more dangerous the whole system is. Therefore, ventilation requirements inside and outside the enclosure must be emphasized.
The influence of the cast resin hv transformer case temperature on the transformer is as follows:
1. In China, when the temperature is the highest in summer, it is usually the time when the power load is the largest. The ambient temperature around the transformer is high and the load is heavy. Dry-type transformers are easily overloaded, and the temperature of the transformer casing naturally rises, affecting the output of the transformer.
2. In the national standard drawing, the area of the ventilation holes of the transformer shell is the effective area, and the effective area of the ventilation holes is less than 1. Some designs fail to notice the difference between open area and open area. The effective area and location of the ventilation holes lead to the fact that the effective ventilation area of the actual transformer room cannot meet the requirements of transformer operation.
3. The size of the distribution room of the new substation is limited by the column distance across the building. Some require that the external dimensions of the transformer should not be too large, and the distance between the transformer casing and the wall should be small, which directly affects the ventilation effect around the transformer.
