How to Solve the Problem of Abnormal Sound and Odor of Oil-immersed Transformer

Oil-immersed transformers generally have obvious characteristics when they fail, such as: strange sound, white smoke and unpleasant irritating smell. Once the oil-immersed transformer fails, it is necessary to carry out related repair work. How does the oil-immersed transformer handle these problems?

If the oil-immersed transformer fails internally or the components in the oil-immersed transformer are overheated, it will cause changes in the odor and color of the oil-immersed transformer oil and components. These changes require attention in the work. Here are some common questions:

(1) The fastening part of the casing terminal is loose or the nose of the lead wire is slippery, etc., the contact surface is severely oxidized, the contact is overheated, the color is darkened and the gloss is lost, and the surface plating is also damaged.

(2) The oil-immersed transformer has poor magnetic disconnection capability and uneven magnetic field distribution, which will cause eddy currents, causing local overheating of the oil-immersed transformer tank and causing discoloration of the paint.

(3) The explosion-proof membrane of the explosion-proof pipe will cause water and moisture to enter the oil-immersed transformer, resulting in the emulsification of the insulating oil and the insulation strength of the oil-immersed transformer.

(4) The casing is corona and flashover due to fouling. Casing flashover discharges can cause aging due to heat generation, damage to insulation and even explosion, and ozone odor.

(5) The cooling fan and the oil pump will burn out and emit a scorching odor.

(6) In addition, excessive moisture absorption, damage to the gasket, excessive amount of water entering the oil chamber, etc. may cause discoloration of the moisture absorbent.

The above description can only be used as a preliminary judgment on the scene of the oil immersed transformer failure. Because the failure of an oil-immersed transformer is not just a visual reflection of one aspect, it involves many factors, sometimes even illusions. Therefore, only by detailed measurement and analysis can the fault cause be accurately and reliably identified, the nature of the accident be identified, and reasonable treatments should be proposed to eliminate the fault as soon as possible.