摘要
高压直流电缆接头的内部温升是反映其运行状态的重要指标。基于线路热场特性和接头结构特征,提出一种计及轴向传热效应的高压直流电缆接头等效稳态热路模型,建立对应热平衡方程及详细求解流程,并以±160kV直流电缆接头为例,进行稳态温度场的求解及分析。研究结果表明,模型计算数据与有限元仿真解的偏差较小,在各线芯节点上的温度偏差未超过1℃,证明所建立模型具有足够的精度;沿线芯的轴向温度分布呈现中间接头高、两侧本体低的特征,即存在由接头向本体的热量传递;随着线芯电流的增大及环境温度的升高,接头轴向传热范围变大,推荐绝热边界距离为5m;利用所建立模型提出一种基于接头表面温度推算线芯温度的反演方法,可结合接头表面实测温度数据,确定线芯温度分布,实现对接头运行状态及导体连接件电阻的评估。
Internal temperature rise of high voltage direct current(HVDC)cable joint is essential indicator to reflect its operation status.Based on thermal characteristic of cable line and structural features of joints,steady-state thermal circuit mode of HVDC cable joints considering axial heat transfer effect was proposed.Model-based thermal equilibrium equations were established,and detailed solution process was introduced.±160 kV DC cable joint was taken as a case to demonstrate the solution and analysis of steady-state thermal field.Results showed that the deviation between calculation data of thermal circuit model and solution of finite element method(FEM)model was small,temperature deviation on each conductor node was less than 1℃,which testified the sufficient accuracy of thermal circuit model.Axial temperature distribution characteristic along the central conductor was calculated to show that temperature was higher in the middle of joint and lowers down to the end,indicating the existence of heat transfer from joint to cables on both sides.With the higher load current and ambient temperature,the range of axial heat transfer from the joint becomed wider,and the adiabatic boundary distance was recommended to be 5 m.In addition,a method was proposed on how to deduce conductor temperature from surface temperature of the joint.Based on it,temperature data measured on the joint surface could be effectively utilized to determine temperature distribution of the central conductor,which was helpful for the evaluation of joint status and conductor connector resistance.
作者
王星洁
刘潇镁
蔡文博
刘英
徐海宁
杨红军
韩俊杰
WANG Xingjie;LIU Xiaomei;CAI Wenbo;LIU Ying;XU Haining;YANG Hongjun;HAN Junjie(State Grid Wenzhou Electric Power Supply Company,Wenzhou 325000,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;State Grid Zhoushan Electric Power Supply Company,Zhoushan 316000,China)
出处
《电线电缆》
2025年第6期9-18,共10页
Wire & Cable
基金
国家电网浙江省电力有限公司科技项目(5211WZ230007)。
关键词
高压直流电缆接头
稳态温度场
轴向传热效应
等效稳态热路模型
导体连接件电阻
HVDC cable joints
steady-state temperature field
axial heat transfer effect
equivalent steady-state thermal circuit model
conductor connector resistance
