典型敷设环境下超高压海底电缆的热特性

Thermal Characteristics of EHV Submarine Cable in Typical Layout Environments

典型敷设环境下超高压(extra-high voltage,EHV)交联聚乙烯(crosslinking polyethylene,XLPE)绝缘海底电缆系统的热特性研究对线路、性能优化和电网安全均有重要意义。首先采用有限元法分析了典型敷设环境下海底电缆的热场分布,然后以2条500 kV XLPE海底电缆为试验线路,在敷设环境为直埋、隧道内、穿管内和空气中,持续运行1年,得到了4种典型环境下海底电缆系统沿线的温度分布。研究结果表明:环境温度约为0~10℃时,穿管段的温度最高;环境温度约为10℃时,穿管段或空气段的温度最高且相近;环境温度约为10~40℃时,空气段的温度最高;穿管段和空气段是海底电缆系统实时温度测控的关键点和工程应用的薄弱点。该研究可为海底电缆系统的优化设计和运行维护提供借鉴。

Study on the thermal characteristics of extra-high voltage(EHV)crosslinking polyethylene(XLPE)submarine power cable in typical layout environments is of important significance for performance optimization and power system security.Firstly,the thermal field distribution of submarine power cable in typical layout environments was analyzed by the finite element method.Two 500 kV XLPE submarine power cable systems were taken as experimental lines under four typical layout environments such as being directly buried,inside tunnel,inside pipe,and in the air.After being continuously operated for one year,the temperature distribution along the submarine power cable systems was obtained.The results show that when the ambient temperatures is from 0℃to 10℃,the highest temperature of cable appears inside the pipe;when the ambient temperature is about 10℃,the highest temperature of cable appears inside the pipe or the air,and close to each other;when the ambient temperatures is from 10℃to 40℃,the highest temperature of cable appears in the air.The temperatures of submarine power cable system inside the pipe and in the air can be used as the key position of real-time temperature measurement and control,which are weak links in engineering application.The research may offer references for optimization design and operation maintenance of submarine power cable system.