摘要
电流互感器(CT)感应取电是目前输电线缆在线监测设备最有效的供能方式。但输电线缆低电流会导致CT无法取能,进而会导致设备供能死区情况发生,危及电力系统安全。因此提出了一种基于锰锌铁氧体与硅钢片串联组合式CT磁芯结构以解决CT低电流取能问题。为验证该磁芯结构低电流取能的有效性,通过采用叠加磁通法给出组合式磁芯结构不同材料占比λ与初始磁导率的关系,进而得到满足实际项目需求的λ值。为了验证理论分析的正确性,搭建了一套CT取能实验平台。实验结果表明,在输电线缆低电流为12 A时,组合式磁芯结构比常规硅钢片取能CT的感应电压提高约30%,重量减少约15%,整体功率提高约24%,进而最大限度解决了供能死区问题,具有一定的工程实用价值。
Current transformer(CT)inductive energy extraction is the most effective power supply method for online monitoring equipment of power transmission cables.However,the low current of the transmission cable will cause the CT to fail to obtain energy,which will lead to the occurrence of equipment energy supply dead zone,and endanger the safety of the power system.Therefore,a CT magnetic core structure based on series combination of Mn-Zn ferrite and silicon steel sheet was proposed to solve the problem of CT low current energy extraction.In order to verify the effectiveness of the low-current energy extraction of the core structure,the relationship between the ratioλof the different materials of the combined core structure and the initial permeability was obtained by using the superimposed magnetic flux method,and then the value ofλthat meets the actual project requirements was obtained.A CT energy extraction experimental platform was set up to verify the correctness of theoretical analysis.The experimental results show that when the low current of the transmission cable is 12 A,the combined magnetic core structure can increase the induced voltage by about 30%,reduce the weight by about 15%,and increase the overall power by about 24%compared with the conventional silicon steel sheet energy extraction CT,and the problem of energy supply dead zone is solved to the maximum extent,which has a certain engineering practical value.
作者
程志远
吴龙飞
李峥
隋立程
吴晓婷
CHENG Zhiyuan;WU Longfei;LI Zheng;SUI Licheng;WU Xiaoting(College of Electrical Engineering,Shanghai University of Electric Power,Shanghai 200090,China)
出处
《电气传动》
2022年第16期26-31,36,共7页
Electric Drive
基金
国家自然科学基金(51977127)。
关键词
低电流
互感器取能
磁导率
输电线缆
low current
transformer energy extraction
permeability
transmission cables
