直流偏磁下500kV单相变压器振动噪声的试验研究  

Experiment on Vibro-Acoustic Characteristic of 500kV Single-Phase Transformer under DC-Bias

作　　者：李冰 王泽忠[1] 刘海波 李海明 刘健犇 Li Bing;Wang Zezhong;Liu Haibo;Li Haiming;Liu Jianben(Beijing Key Laboratory of High Voltage&EMC North China Electric Power University,Beijing 102206 China;State Key Laboratory of Power Grid Environmental Protection China Electric Power Research Institute,Wuhan 430074 China;State Grid East Inner Mongolia Electric Power Company,Hohhot 010010 China)

机构地区：[1]高电压与电磁兼容北京市重点实验室(华北电力大学),北京102206 [2]电网环境保护国家重点实验室(中国电力科学研究院武汉分院),武汉430074 [3]国网内蒙古东部电力有限公司,呼和浩特010010

出　　处：《电工技术学报》2021年第13期2801-2811,共11页Transactions of China Electrotechnical Society

基　　金：国家重点研发计划(2016YFC0800100);电网环境保护国家重点实验室开放基金(GYW51201901088)资助项目。

摘　　要：直流偏磁是电力变压器的一种非正常工作状态,直流流入变压器后将在铁心中产生直流磁通,导致变压器铁心出现半波饱和、励磁电流严重畸变、局部过热、振动噪声增加等一系列问题,并且大容量单相自耦变压器更易受到直流偏磁的影响,对电网的安全稳定运行产生了严重的威胁。该文利用两台参数一致的250MV·A/500kV变压器分别进行了空载和负载直流偏磁试验,对变压器直流偏磁下的电压畸变率、励磁电流、振动和噪声进行测量,并分析研究其直流偏磁下的变化趋势、分布规律和频谱特征。试验结果为大型变压器在实际运行情况下的直流偏磁耐受能力评估及直流偏磁下的振动噪声特性研究提供参考依据。DC bias is an abnormal working state of transformer.The main effect of a DC current flowing into a transformer winding is the half-cycle magnetic core saturation,as a result,a series of problems occur,such as the serious distortion of excitation current,partial overheating and increase of vibro-acoustic noise.The big capacity single-phase autotransformer has less tolerance to the DC bias current,which have a serious threat to the safe and stable operation of the power grid.In this paper,two identical 250MV·A/500kV transformers are used for DC bias experiments with and without load.The voltage distortion rate,excitation current,vibration and noise under DC bias of the transformer are measured,and the variation,distribution and harmonics spectrum characteristics under DC bias are analyzed.The test results would provide a reference for the assessment of DC endurance capability and the study of vibro-acoustic noise characteristics of large capacity transformers in actual operation.

关 键 词：大容量变压器 直流偏磁 负载试验 振动噪声 

分 类 号：TM153[电气工程—电工理论与新技术] TM41