一起1000 kV并联电抗器局部放电缺陷的诊断分析

Diagnosis and Analysis of a Partial Discharge Defect in a 1000 kV Shunt Reactor

针对1000 kV并联电抗器乙炔问题,综合采用铁芯夹件接地电流、高频脉冲电流法、特高频法以及超声波法等综合带电检测手段,提出采用特高频、高频局部放电联合定位及高频、超声波局部放电联合定位方法对该并联电抗器进行故障诊断与定位,最终确定出现乙炔原因为铁芯夹件之间绝缘故障。为有效降低环流并限制放电,提出采用铁芯夹件串接电阻的方式来减少放电现象的发生,实现了夹件接地电流降至原有的1/7,高频放电信号幅值降低到原来的1/5。所提方法能够为电抗器内部绝缘的故障诊断与处理提供参考。

The fault diagnosis and location of a 1000 kV shunt reactor acetylene over standard problem were carried out by using the integrated live detection methods such as iron clip grounding current,high frequency pulse current method,ultra high frequency(UHF)method and ultrasonic method.The joint location methods of UHF and high frequency partial discharge and the joint location methods of high frequency and ultrasonic partial discharge were proposed to diagnose and locate the fault of the shunt reactor.It was determined that the cause of acetylene exceeding the standard was the insulation fault between the core clamps.In order to effectively reduce the circulating current and limit the discharge,the method of connecting the core clamps in series with resistors was proposed to reduce the discharge phenomenon.The grounding current of the clamps was reduced to 1/7 of the original value,and the amplitude of high frequency discharge signal was reduced to 1/5 of the original value.The proposed method can provide references for fault diagnosis and treatment of internal insulation of reactor.