基于超高频传感器的电力变压器局部放电定位研究  

Research on Partial Discharge Location of Power Transformer Based on UHF Sensor

作　　者：席禹 林冬 于力 陈波 XI Yu;LIN Dong;YU Li;CHEN Bo(Digital Grid Research Institute,China Southern Power Grid,Guangzhou 510000,China)

机构地区：[1]南方电网数字电网研究院有限公司,广东广州510000

出　　处：《绝缘材料》2022年第12期80-86,共7页Insulating Materials

基　　金：中国南方电网有限责任公司科技项目(670000KK52200134)。

摘　　要：局部放电(partial discharges,PD)是导致电力变压器绝缘故障的重要因素,因此,局部放电源的定位对于变压器的评估和维修至关重要。本文提出一种基于超高频(ultra high frequency,UHF)传感器的局部放电定位技术,采用在变压器内部安装传感器的方法来克服外部电晕放电等测量干扰问题,通过对单个UHF传感器进行适当的信号处理来准确地识别电力变压器内的单个局部放电源。为了验证这一方法,在变压器油中进行了点对球放电(point to sphere discharge,PS)、表面放电(surface discharge,SD)和悬浮电位放电(floating potential discharge,FP)3类局部放电实验,验证支撑这一方法的5个条件的准确性。结果表明:局部放电活动产生的UHF信号独立于局部放电类型,并且包含从局部放电源到超高频传感器过程中特有的畸变特性,也包含了其在结构位置中特定的信号特征。因此,证明了单个UHF传感器识别变压器内单个局部放电源的可行性。Partial discharge(PD)is an important factor leading to insulation faults of power transformers.Therefore,the location of PD sources is crucial for the assessment and maintenance of transformers.In this paper,a PD location technology based on ultra high frequency(UHF)sensor was proposed.The sensor was installed inside the transformer to overcome the measurement interference problems such as external corona discharge.Through proper signal processing on the single UHF sensor,a single PD source in the power transformer could be accurately identified.In order to verify this method,three kinds of PD experiments,namely point to sphere discharge(PS),surface discharge(SD),and floating potential discharge(FP)were carried out in transformer oil to verify the accuracy of five conditions supporting this method.The results show that the UHF signal generated by PD activity is independent of the type of partial discharge,and contains the unique distortion characteristics in the process from the PD source to the UHF sensor,as well as the specific signal characteristics in the structure position.Therefore,it is proved that it is feasible for a single UHF sensor to identify a single PD source in the transformer.

关 键 词：超高频 电力变压器 局部放电 放电源定位 

分 类 号：TM411[电气工程—电器]