摘要
电容电流过大是电力电缆线路最重要的问题之一。为减小电力电缆线路的对地电容电流，对传统电力电缆进行了创新设计，在电力电缆线芯外添加了磁粉层而成为大电感电力电缆。介绍了大电感电力电缆电感和电容的计算方法。建立了大电感电力电缆和传统电力电缆的ANSYS有限元仿真模型，对它们的导体电阻、绝缘电阻、电感、电容、集肤效应和涡流损耗进行了对比分析；建立了2种电力电缆的基于MATLAB的对地电容电流仿真模型，并对它们的对地电容电流和接地故障时的暂态电容电流进行了对比分析。结果表明：大电感电力电缆能够满足传统电力电缆的基本技术要求；根据磁粉量的大小不同，大电感电力电缆的单位长度电感值可达传统电力电缆的2～10倍，电容电流比传统电力电缆减小10％～20％，涡流损耗比传统电力电缆减小1％；并且磁粉层越厚，电容值就越小。因此，增加磁粉层，不仅能减少电容，从源头上减少电力电缆的电容电流，而且能降低电力电缆的集肤效应和涡流损耗。
Excessive capacitance current has been one of the most important problems to power cable transmission lines. In order to reduce the line-to-ground capacitance current, we developed large-inductance power cable through adding a magnetic layer to the core of conventional power cable. Methods for calculating the inductance and capacitance of this large-inductance cable were presented. Moreover, we established finite element simulation models of both large-capacitance cable and conventional cable in ANSYS to compare them in the aspects of conductor resistance, insulation resistance, inductance, capacitance, skin effect, and eddy current loss. Capacitance current to ground and tran- sient capacitance current under grounding faults of the two kinds of cables were also compared using models of capacitance current to ground established in MATLAB. The results show that, while meeting all the basic technical requirements of conventional power cables, the large-inductance cable has inductance per unit length as 2-10 times much as that of conventional power cables, along with capacitive current will be reduced by 10%～20%, and eddy current loss will be reduced by 1%. The capacitance can be further decreased by thickening the magnetic layer. Therefore, by adding magnetic layer to power cables, not only it is able to reduce their capacitance which consequently lowers the earth capa- citance current, but also the skin effect and eddy current loss are suppressed.
出处
《高电压技术》
EI
CAS
CSCD
北大核心
2015年第8期2635-2642,共8页
High Voltage Engineering
基金
湖南省重大科技专项基金(06GK1003-1)~~
关键词
大电感电力电缆
磁粉
电感
电容电流
有限元分析
涡流损耗
large inductance power cable
magnetic particles
inductance
capacitance current
finite element analysis
eddy current loss
