直流偏磁条件下高精度微型电流互感器的传变特性  

Transfer Characteristics of High Precision Micro Current Transformer under DC Bias

作　　者：李春来[1] 汤晓宇[2] 罗坤明[1] 兰雄 LI Chun-Lai;TANG Xiao-Yu;LUO Kun-ming;LAN-Xiong

机构地区：[1]河源职业技术学院,广东省智能低压电气设备工程技术研究中心,广东河源517000 [2]广东雅达电子股份有限公司,广东河源517000

出　　处：《仪表技术与传感器》2019年第5期124-126,共3页Instrument Technique and Sensor

基　　金：广东省科技厅高新技术产业化基金项目(2013B010101016);河源市科技计划基金项目(河科(2014)73号);2018年度省科技创新战略专项资金(纵向协同管理方向)项目(河科[2019]11号)

摘　　要：高精度微型电流互感器(CT)是高端智能电力仪表常用的前端取样器件,其传变特性受直流偏磁的影响。以 0.02 级微型电流互感器为例,通过实验数据来定量分析直流偏磁对 CT 传变特性的影响。研究表明,CT 传变特性受直流偏磁的影响,这种影响随直流偏磁电流的增大而增大;角差随直流偏磁电流的增大而向正方向变化,随直流偏磁电流的增大而呈非线性快速增长;当直流偏磁电流超过微型电流互感器一次侧交流电流有效值的 2%时,比差超出 0.02 级 CT 比差误差限值。直流偏磁将导致仪表测量偏小。High precision miniature current transformer (CT) is a common front end sampling device for high end intelligent power meters. Its transfer characteristics are affected by DC bias. Taking 0.02 class miniature current transformer as an example, the influence of DC bias on the transmission characteristics of CT is quantitatively analyzed by experimental data. The results show that the transmission characteristics of CT are affected by DC bias, which increases with the increase of DC bias current. The angular difference changes with the increase of DC bias current in the positive direction, and increases nonlinearly with the increase of DC bias current. When DC bias current exceeds 2% of the effective value of AC current on the primary side of micro current transformer, the ratio difference exceeds 0.02 CT error. DC bias canl lead to smaller instrument measurement.

关 键 词：直流偏磁 高精度微型电流互感器 传变特性 比差 角差 

分 类 号：TM452[电气工程—电器]