现场校准用磁调制式直流电流比较仪磁屏蔽结构仿真研究与设.doc

现场校准用磁调制式直流电流比较仪磁屏蔽结构仿真研究与设计* 林国营1，潘峰1，易斌1，1，徐雁2，柏航2 （1．广东电网有限责任公司电力科学研究院， 广州 510080； 2. 华中科技大学电气与电子工程学院， 武汉 430074） 摘要： 关键词：直流电流互感器；现场校准；直流电流比较仪；磁屏蔽中图分类号：TM933 文献标识码：B 文章编号： Simulation study and design of the magnetic shielding structure of the DC current comparator based on magnetic modulator for field calibration Lin Guoying1, Pan Feng1, Yi Bin1, Zhang Dingqu1, Xu Yan2, Bai Hang2 (1. Electric Power Research Institute of Guangdong Power Grid Co., Ltd., Guangzhou 510080, China. 2. School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China) Abstract: Strong electromagnetic interference and some uncertain environmental factors exit when the direct current (DC) transformer is calibrated on the work field. Therefore, the standard DC current comparator should not only have much high measuring accuracy, but also require the strong ability to resist electromagnetic interference. Firstly, the paper establishes the simulation model of the magnetic shielding structure of the direct current comparator (DCC) based on magnetic modulator with the ANSYS software, which is used as the reference for the field calibration. The influence of the thickness of the shielding, magnetic conductivity of the shielding material and gap on the magnetic shielding effectiveness is analyzed. According to the simulation results, the design of the magnetic shielding structure is carried out. Secondly, this paper analyzes the influence of the eccentric bus and interference magnetic field generated by the nearby conductor on the measuring accuracy of the DCC without and with the magnetic shielding structure respectively. In the end, the prototype of the DCC with the nominal parameter of 5000A:5A is developed. The testing results of the prototype confirm the simulation results and the effectiveness of the designed structure. The total accuracy of the developed DCC is up to 0.005 level, which is satisfied with the req