Transformer winding maximum temperature at?
From the heat point of view, each part of the winding are the same, the maximum temperature of the transformer winding in the worst part of the heat dissipation, generally in the middle of the inner winding.
National standard "dry-type transformers" GB6450-1986 on the dry-type transformer temperature limit to make the provisions. 1, the dry-type transformer coil, when the use of A-class insulation material, the ultimate operating temperature of 105 ℃, the maximum temperature rise should be less than 60 ℃; when the use of E-class insulation material, the limit operating temperature at 120 ℃ , The maximum temperature rise should be less than 75 ℃; when using B-class insulation material, the extreme working temperature at 130 ℃, the maximum temperature rise should be less than 80 ℃; when using F-class insulation material, the limit operating temperature at 155 ℃ , The maximum temperature rise should be less than 100 ℃; when the use of H-class insulation material, the limit operating temperature at 180 ℃, the maximum temperature rise should be less than 125 ℃; when using C-class insulation material, the extreme working temperature at 220 ℃ , The maximum temperature rise should be less than 150 ℃.
National standard (oil-immersed transformer) the top of the oil temperature is generally adjusted at 85 ℃, if more than 85 ℃, to analyze the reasons: 1, if it is because the room temperature is too high, heavy load and other slowly rising, you can continue to run more than 85 ℃, but The maximum temperature can not exceed 95 ℃ (when the transformer core core or winding is 105 ℃, will seriously damage the insulation, shorten the life or burn the transformer); 2, the transformer running at 85 ℃, the transformer oil temperature and room temperature difference can not exceed 55 ℃, if it is over, may be a serious overload, the voltage is too low, the current is too large, internal failure, etc., continue to run will seriously damage the insulation, shorten the life or burn the transformer.