电力变压器剩磁的仿真拟合及验证  

Simulation fitting and verification of power transformer remanence

作　　者：孔煜斌 KONG Yubin(China Energy Engineering Group Shanxi Electric Power Engineering Co.Ltd.,Taiyuan 030001,China)

机构地区：[1]中国能源建设集团山西省电力勘测设计院有限公司,山西太原030001

出　　处：《兵器材料科学与工程》2025年第2期150-156,共7页Ordnance Material Science and Engineering

摘　　要：电力变压器在投入运行后铁芯内部会产生剩磁,导致在后续的空载合闸等操作中产生励磁涌流,对电网运行产生不利影响。因此预先对铁芯剩磁值进行测量研究,对于后续遏制励磁涌流的出现具有积极意义,而目前尚无合适的设备来对电力变压器剩磁进行准确测量。考虑到工程领域的电力变压器多为三相柱式的铁芯,本文选择方形铁芯为研究对象,寻找合适且能够准确测量铁芯剩磁值的方法,以便后续退磁,从而遏制励磁涌流出现。首先探究了铁芯剩磁的测量原理,基于场路耦合建立了测量回路中暂态物理量与剩磁值的关系,同时阐述了剩磁方向的概念及判断方法。其次,对方形铁芯的充磁过程、剩磁测量进行了有限元仿真建模及分析。分别对预设剩磁值与测量回路正向、反向输入能量值的关系建立了拟合曲线与表达式,并进行了统计学误差分析。最后搭建了剩磁测量平台,对单相变压器方形铁芯进行剩磁测量实验。结果表明:正向输入能量值拟合的剩磁值与实际预设剩磁值相对误差不超过4%,且剩磁值较小时拟合值比暂态电流法更准确。After being put into operation,the power transformer will have remanence in the iron core,resulting in the no⁃load closing operation of the excitation inrush current,which will have an adverse effect on the operation of the power grid.Therefore,measuring and studying the core remanence in advance is of positive significance for curbing the occurrence of excitation inrush current.However,there is currently no suitable equipment to accurately measure the remanence of power transformers.Considering that most power transformers in the engineering field have three⁃phase column cores,this article chooses square cores as the research object to find a suitable and accurate method for measuring the core's remanence value for subsequent demagnetization,thereby curbing the occurrence of excitation inrush currents.Firstly,the principle of magnetic measurement was explored,and the relationship between the temporary physical quantity of the measuring circuit and the remanence were establishedbased on field⁃circuit coupling.At the same time,the concept and judgment method of the remaining magnetic direction was illustrated.Secondly,the magnetization process and remanence measurement of the iron core were modeled and analyzed by finite element simulation.The relationship between the preset remanence value and the forward and reverse input energy value of the measurement loop was established,and the statistical error analysis was carried out.Finally,the platform of remanence measurement was built,and the remanence measurement experiment was carried out on the square core of single⁃phase transformer.The results show that the relative error between the remanence value fitted by the forward input energy value and the actual preset remanence value is less than 4%,and the fitting value is more accurate than the transient current method when the remanence value is small.

关 键 词：剩磁 能量值 有限元仿真 误差分析 

分 类 号：TM406[电气工程—电器]