基于双联合定位法的500 kV变压器内部放电诊断分析

Diagnosis and Analysis of Internal Discharge in 500 kV Transformer Based on Joint Positioning Method

单一使用常规的超高频法、超声波法以及高频电流法进行带电检测变压器局部放电存在局限性。同时,变电站电磁环境干扰大、变压器运行中持续振动干扰以及其金属封闭结构导致变压器内部局部放电检测与定位成功率低。提出了双联合定位法,即高频电流与特高频联合定位以及声电联合定位法,利用该方法准确判断一起500 kV变压器内部放电的故障,返厂解体检查情况与现场定位结果完全一致,验证了该方法的有效性。

There are limitations in using common ultra high frequency method,ultrasonic method and high frequency current method individually to detect internal discharge in transformer.At the same time,the large electromagnetic environment interference of substation,continuous vibration interference during the operation of transformer,and its metal closed structure cause the low success rate of detection and location of internal partial discharge.A joint positioning method is proposed,that is,acoustic and electrical joint positioning method with high frequency current and ultra high frequency joint positioning,which can accurately judge the failure of internal discharge in 500 kV transformers.The disassembly inspection of the transformer after returning to the factory is completely consistent with the results of on-site positioning,which verifies the effectiveness of the proposed method.