摘要
直流偏磁会改变计量用电流互感器(TA)的传变特性,影响仪表测量、电能计量的准确性。通过建立等效电路模型,仿真直流偏磁前后励磁电流波形变化情况,定性分析出直流偏磁电流造成TA误差增大。基于TA电磁关系方程,利用全波傅里叶算法导出了TA传变误差的解析表达式。仿真算例验证了理论分析结果的正确性,定量给出了不同因素和直流偏磁共同作用下TA的三维误差曲线,表明比差、角差随直流偏磁电流的增大而增大,为计量用TA的设计和参数整定提供了科学依据。
Direct current (DC)flowing with the first winding current of current transformers (CT) causes a DC component in the magnetizing current. And it directly impacts the accuracy of measurement and power metering. This paper qualitatively analyses that errors of CTs increase with DC bias uses the equivalent circuit models and simulation of magnetizing current. Based on a full-wave Fourier algorithm, a suitable approximate solution of electromagnetic equation provides expressions for the ratio error and phase displacement. Simulation and case study are given to verify the above analysis results, and the computed results agree well with the simulated ones. The 3D error curves are quantitatively obtained to show that the ratio error and phase displacement increase with the DC bias, which provides scientific basis for measuring the design and specifications of the CT.
出处
《高压电器》
CAS
CSCD
北大核心
2013年第11期104-109,共6页
High Voltage Apparatus
关键词
电流互感器
直流偏磁
比差
角差
current transformer
DC bias
ratio error
phase displacement
作者简介
田晓倩(1987-),女,硕士研究生,研究方向为现代电磁测量技术,从事电流互感器直流偏磁方面的研究工作。
李宝树(1955-),男,教授,硕士研究生导师,研究方向为现代电磁测量技术和现代电能质量。
申路(1989-),男,硕士研究生,研究方向为直流偏磁抑制措施。