直流偏磁下大型变压器的振动和噪声特性分析及特征识别方法研究  

Analysis of Vibration and Noise Characteristics of DC-biased Large-scale Transformer and Research on Characteristics Recognition Method

作　　者：李唐兵 许加柱[2] 童涛 徐碧川 曾磊磊 LI Tangbing;XU Jiazhu;TONG Tao;XU Bichuan;ZENG Leilei(Electric Power Research Institute,State Grid Jiangxi Electric Power Co.,Ltd.,Nanchang 330096,China;College of Electrical and Information Engineering,Hunan University,Changsha 410082,China)

机构地区：[1]国网江西省电力有限公司电力科学研究院,南昌330096 [2]湖南大学电气与信息工程学院,长沙410082

出　　处：《电源学报》2025年第2期133-141,共9页Journal of Power Supply

基　　金：国网江西省电力有限公司科技资助项目(52182020009A)。

摘　　要：直流偏磁是引起大型变压器振动加剧和噪声增大的主要原因之一,全面掌握直流偏磁下大型变压器振动和噪声特征,对变压器的运行状态评估和降噪减振至关重要。以某一406 MVA超高压大型变压器为研究对象,开展振动和噪声特性研究:首先,基于场路耦合有限元法,仿真分析其在不同直流偏磁电流下的空载运行特性,以及不同直流偏磁下励磁电流规律,进而建立电路-磁场-固体力学-压力声学多物理场耦合模型,并考虑磁致伸缩的影响,求得直流偏磁下变压器不同测量点的振动位移有效值和噪声信号时频特性;然后,对变压器周围不同测量点进行声级测定,将仿真值与实测值进行对比,验证所提变压器振动噪声计算方法的有效性;最后,采用希尔伯特-黄变换HHT(Hilbert-Huang transform)方法提取直流偏磁下大型变压器的振动和噪声特征量,提出1种基于噪声信号本征模态函数能量比的变压器振动特征识别方法。该方法能有效识别变压器直流偏磁的严重程度,准确掌握变压器的运行状态,为及时采取抑制直流偏磁措施提供理论依据。Since DC bias is one of the main reasons for increases in the vibration and noise of a large-scale transformer,it is essential to fully understand the vibration and noise characteristics of large-scale transformers under DC bias for the evaluation of the operating state of transformers and the reduction of noise and vibration.A 406 MVA EHV large-scale transformer is taken as the research objective,and its vibration and noise characteristics are studied.First,based on the field-circuit coupling finite element method,the no-load operation characteristics under different DC bias currents are simulated and analyzed,and the law of excitation current under different DC biases is analyzed.Second,a multi-physics coupling model of circuit-magnetic field-solid mechanics-pressure acoustics is established,and the effective value of vibration displacement and the time-frequency characteristics of noise signal at different measuring points of the transformer under DC bias are obtained considering the influence of magnetostriction.Third,the sound level is measured at different measuring points around the transformer,and the simulated value is compared with the actual measured value to verify the effectiveness of the proposed calculation method for transformer vibration and noise.Finally,the Hilbert-Huang transform method is used to extract the vibration and noise characteristic quantities of one large-scale transformer under DC bias,and a transformer vibration characteristic recognition method based on the energy ratio of the noise signal intrinsic mode function is proposed.This method can effectively recognize the severity of DC bias of the transformer and accurately grasp its operating state,providing a theoretical basis for timely taking measures to suppress the DC bias.

关 键 词：直流偏磁 振动噪声 多物理场耦合 变压器 本征模态函数 

分 类 号：TM41[电气工程—电器]