直流偏磁下开磁路电压互感器传变特性仿真研究  

Simulation study on transfer characteristics of voltage transformer with open magnetic circuit under DC magnetic bias

作　　者：王健 刘浩 刘俭 汪根荣 杜百稳 WANG Jian;LIU Hao;LIU Jian;WANG Genrong;DU Baiwen(China Electric Power Research Institute Co.,Ltd.,Wuhan 430074,China)

机构地区：[1]中国电力科学研究院有限公司,湖北武汉430074

出　　处：《中国测试》2022年第9期177-184,共8页China Measurement & Test

基　　金：国网总部科技项目(5100-202155308A-0-0-00)。

摘　　要：电压互感器的磁通在直流偏磁条件下将发生偏移,导致铁心工作在非线性区,造成电压互感器计量误差急剧增大。为克服传统电压互感器抗直流偏磁能力不足的问题,提出“T字型”铁心结构的开磁路电压互感器。分析开磁路电压互感器的抗直流偏磁原理,设计电气铁路用25 kV电压互感器参数,基于有限元方法计算不同直流偏磁电压下互感器的磁场分布特性和二次电压波形,利用三参数正弦曲线拟合算法获得互感器的比值误差和相位误差,采用RC元件和小互感器组成的补偿回路对误差进行补偿,使互感器满足0.5级现场计量要求。该研究可为抗直流偏磁电压互感器设计提供参考。The magnetic flux of voltage transformer will shift under the condition of DC magnetic bias,resulting in the iron core working in the non-linear zone and the measurement error of voltage transformer increasing sharply.In order to overcome the problem of insufficient ability to resist DC magnetic bias of traditional voltage transformer,the open magnetic circuit voltage transformer with‘T’core structure is proposed.The anti-DC magnetic bias principle of the voltage transformer with open magnetic circuit is analyzed,and the parameters of the 25 kV voltage transformer for electric railway are designed.Based on the finite element method,the magnetic field distribution characteristics and the secondary voltage waveforms of the transformer under different DC bias voltages are calculated.The ratio error and phase error of the transformer are obtained by using the three-parameter sine curve fitting algorithm.The compensation circuit composed of RC components and small transformers is used to compensate the error,so that the accuracy class of transformer meets the requirement of 0.5 class for on-site measurement.This research can provide reference for the design of anti-DC magnetic bias voltage transformer.

关 键 词：直流偏磁 电压互感器 开磁路 传变特性 误差 

分 类 号：TM451[电气工程—电器]