高压电力电缆土壤导热系数的反演与计算  

nversion of soil thermal conductivity for high voltage power cable

作　　者：覃喜 周文俊 吕鸣 姜玉菡 杨仕友[2] QIN Xi;ZHOU Wenjun;LYU Ming;JIANG Yuhan;YANG Shiyou(Zhejiang Huayun Power Engineering Design Consulting Co.,Ltd.,Hangzhou 310016,China;College of Electrical Engineering,Zhejiang University,Hangzhou 310027,China)

机构地区：[1]浙江华云电力工程设计咨询有限公司,浙江杭州310016 [2]浙江大学电气工程学院,浙江杭州310027

出　　处：《电工电能新技术》2024年第9期94-102,共9页Advanced Technology of Electrical Engineering and Energy

基　　金：浙江华云电力工程设计咨询有限公司科技项目(2019C01D01P04)。

摘　　要：温度和载流量是电缆运行状态及热稳定极限的重要指标参数,精确的土壤导热系数是电缆温度场准确计算的前提和基础。土壤导热系数受多种因素影响,呈现较大差异性和不确定性。为精确计算高压电力电缆实际运行工况下的温度场和载流量,本文提出了电力电缆实时土壤导热系数逆问题的数学模型和计算方法。开发了电缆表皮温度测量的分布式光纤测温系统,基于电缆表面采样点实时温度构建了分层土壤实时导热系数反演数学模型,并提出逆问题求解的改进遗传算法。实例计算结果表明,应用本文成果计算的实时或动态载流量比标称载流量高出38.08%。Temperature is a predominant variable to identify the operating state of buried cables,while ampacity is a performance metric for the thermal stability limit of cables.Because power cables are laid underground,precise constitutive parameters such as soil thermal conductivity are essential and fundamental for accurate calculation of the cable temperature field.However,the thermal conductivities of cable backfill soil and mother soil are affected by cable heat dissipation,region,climate and other factors,which result in significant differences and uncertainties,making it relatively difficult to accurately calculate the ampacity.In order to accurately calculate the temperature field and ampacity of high-voltage power cables under engineering operating conditions,this paper proposes a mathematical model and solution methodology for the real-time inversion of soil thermal conductivity for power cables.First,a distributed optical fiber temperature measurement system for the outer surface temperature of cables is developed to invert the soil thermal conductivity for power cables;then,based on the real-time temperature of typical sampling points on the cable skin,a mathematical model for the real-time inversion of the layered soil thermal conductivity is constructed.Finally,an improved genetic algorithm for solving the inverse problem is proposed.The numerical results show that the real-time or dynamic ampacity calculated using the proposed methodology is about 38.08%higher than the nominal ampacity.

关 键 词：逆问题 改进遗传算法 有限元 导热系数 

分 类 号：TM12[电气工程—电工理论与新技术]