| 引用本文: | 李春来,汤晓宇,黄业安,罗坤明,肖运海.计量用TA在直流偏磁条件下传变特性的实验与分析[J].电力自动化设备,2011,31(7): |
| LI Chunlai,TANG Xiaoyu,HUANG Yean,LUO Kunming,XIAO Yunhai.Measurement and analysis of transfer characteristic for metering CT with DC magnetic bias[J].Electric Power Automation Equipment,2011,31(7): |
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| 摘要: |
| 直流偏磁会改变计量用电流互感器（TA）的传变特性，直接影响仪表测量、电能计量的精度。地磁风暴、直流输电系统、线路故障、人为加入直流分量等都会使TA产生直流偏磁。理论分析表明，直流分量不产生变化磁通，其作为励磁电流改变铁心工况，产生各次谐波，影响TA的正确传变。以计量仪表常用的0.1级TA04－5 A／5 mA为例，通过实验数据来分析研究直流偏磁对TA传变特性的影响。研究表明，直流偏磁使计量用TA的比差向负方向变化，角差向正方向变化，并且这种影响随着直流偏磁电流的增大而增大，尤其是角差呈非线性快速增长，直流偏磁最终导致电力仪表测量、电能计量偏小。 |
| 关键词: 电能计量 互感器 直流偏磁 传变特性 比差 角差 |
| DOI： |
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| 基金项目:广东省科技厅高新技术产业化基金资助项目（2010- B010900011） |
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| Measurement and analysis of transfer characteristic for metering CT with DC magnetic bias |
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LI Chunlai1, TANG Xiaoyu2, HUANG Yean1, LUO Kunming1, XIAO Yunhai1
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1.Department of Electronic and Information Engineering，Heyuan Polytechnic，Heyuan 517000，China;2.Guangdong Yada Electronics Co.，Ltd.，Heyuan 517000，China
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| Abstract: |
| The transfer characteristic of CT（Current Transformer） changes due to DC magnetic bias，which directly impacts the accuracy of measurement. Theoretical analysis indicates that，without magnetic flux variation，the DC component changes the core condition，produces harmonics and affects the transfer characteristic of CT，acting as the excitation current. With the experimental data of CT04-5 A／5 mA，the influence of DC magnetic bias on the transfer characteristic of metering AT is analyzed，which show that，the ratio error changes in negative direction and the phase displacement changes in positive direction，resulting in smaller measurement. |
| Key words: electric power measurement electric transformers DC magnetic bias transfer characteristic ratio error phase displacement |
