When we use the transformer, Xiaobian reminds you to pay attention to avoid accidents. Transformer water ingress and dampness is also an important part of transformer accidents and burnout. Many transformers are in water or continue to operate, so it poses a threat to the safety of power system. The reason why the separation transformer is simple and affected by water and moisture is as follows:
1、 Poor sealing of casing top connecting cap.
When the sealing performance of the connecting cap is not good, moisture enters the winding insulation along the lead, resulting in breakdown accident. The main reasons for poor sealing at the end of casing are unreasonable structure and incorrect rubber pad device.
2、 Damp during maintenance
During the maintenance of transformer hanging cover, the body is exposed to the atmosphere. When the air relative humidity is large, the insulation will absorb moisture in the air. This process starts from the surface insulation. The greater the relative humidity and the longer the time, the deeper the water penetration.
3、 Cracked brass tube of cooler
According to the rules, the cooler shall be subject to leakage test before installation, so as to detect the cracking defect of the cooler. Otherwise, it may lead to insulation breakdown accident. For example, for a 150MVA, l10kv power transformer, during operation, light and heavy gas protection action trips and explosion-proof simple oil injection. According to the inspection of the hanging cover, 24 sections of the lower part of phase a high-voltage winding were burned out, there were 4 short circuits, and the two melted holes were up to 100mm, which was caused by the rupture of the copper pipe of the cooler and the water entering the transformer.
Therefore, we must pay attention when using the transformer. Similarly, when purchasing transformers, you can't just look at the price. Quality is the most important.
