摘要
基于分布式光纤温度测量系统(DTS)测量的温度曲线,识别和定位电缆的所有热点,提出一种有限元方法与基于梯度的优化方法的组合方法,结合电缆沿线最高温度点的结构和安装数据及负载电流,估算土壤热参数,进而实时评估地下电缆的载流量及热状态。以实际应用的一条230kV/500MVA电缆线路为例,对其长期运行额定载流量及紧急过负荷载流量进行了精确的评估,证明了该方法的正确性和有效性。为了恢复整个电缆的载流量,采用一种通过移除电缆沿线热点顶部填土的方法,通过对这种方法进行三维仿真分析,结果表明所提出的方法对于恢复电缆的载流量效果较为明显。
Based on the temperature profile of advanced distributed temperature sensing（DTS） system, all hotspots of an underground cable circuit can be readily identified and located. In this paper, a technique is developed to real-time assess underground cable ratings using cable construction and installation data, load current and estimated soil thermal parameters of the most serious hotspot, which ls accomplished through the use of the finite-element method（FEM） and a gradient-based optimization method. The technique is applied to a 230kV/500MVA cable circuit to show its effectiveness and accurateness in assessment of continuous and emergency ratings. In order to restore the full cable rating, a method is presented to mitigate the hotspot by means of removing top earth filling of a hotspot. The proposed improvement method is proved very useful through a three-dimension finite-element simulation.
出处
《电气技术》
2013年第10期1-1,2-5,18,共6页
Electrical Engineering
基金
江苏省产学研前瞻性联合研究项目(BY2012128)
关键词
电缆载流量
有限元法
优化方法
热点缓和
cable rating
finite element method
optimization method
hotspot mitigation
