Why does the transformer keep buzzing?

1. The internal iron core or clamp of the distribution transformer is loose, the sound becomes louder, and there is intermittent noise. After testing, the load current is not large, the temperature is not high, the secondary no-load voltage is basically balanced, and the operation is not monitored; if the sound continues to increase, replacement and maintenance should be considered.

2. The system is short-circuited or grounded remotely, and the fuse is not blown in time (because the short-circuit current is not too large or the installation capacity of the fuse is too large). Under the action of the short-circuit current, the magnetic circuit of the magnetic flux is seriously damaged. Balanced, strong and uniform noise occurs.

3. When the turns are short-circuited, the short-circuited turns will produce serious local overheating, causing the transformer oil to boil locally, resulting in a "gurgling, gurgling" sound like a boiling pot. The tap-changer has poor contact or insulation breakdown, causing a "crackling" sound of discharge. In such a situation, the secondary no-load voltage of the distribution transformer will be seriously unbalanced, and the oil temperature will also rise. If you unscrew the oil filling hole of the oil pillow, you will smell a burnt smell. The distribution transformer should be stopped and sent to the factory for maintenance.