一起220 kV变电站主变噪音异常案例

A Case of Abnormal Noise of Main Transformer in 220 kV Substation

正常运行的变压器发出持续均匀的“嗡嗡”声,是因为交流电流经过变压器绕组时,在铁芯中产生周期性变化的交变磁通,随着磁通的变化,引起铁芯的振动,从而发出均匀的“嗡嗡”声。如果声音不均匀或有其他异常声音出现,均属不正常运行声。声音的变化可以在一定程度上反应变压器内部或外部的异常情况。如变压器发出均匀沉重的“嗡嗡”声,无杂音,可能是变压器负荷增加引起的;变压器的“嗡嗡”声大而嘈杂,声音中有“叮当”等有规律的撞击声,可能是由于铁芯紧固螺栓等内部结构松动受到振动而引起的[1]。

A continuous and uniform“buzzing”sound occurs in the normal operation of the transformer.This is because when the AC current passes through the transformer winding,the periodic alternating magnetic flux is produced in the iron core.With the change of the magnetic flux,the vibration of the iron core will be caused and the uniform“buzz”sound will be emitted.If the sound is uneven or there are other abnormal sounds,it belongs to abnormal operation sound.The change of sound can reflect the abnormal situation inside or outside the transformer to a certain extent.If the transformer makes a uniform heavy“buzz”sound without noise,it may be caused by the increase of transformer load.The“buzz”of the transformer is loud and noisy,and there are regular impact noises such as“Ding Ding”in the sound,which may be caused by vibration caused by looseness of internal structure such as iron core fastening bolts[1].