地下电缆排管涡流损耗及经济性分析

为解决传输线电流在传统钢筋混凝土地下电缆排管中产生涡流损耗而造成电能浪费的问题,将有限元数值分析技术应用于地下复杂环境涡流-温度场的分析和计算。提出了地下电缆排管涡流-温度耦合场的三维有限元模型,兼顾求解速度和计算精度需求的剖分方法以及多物理耦合场的迭代求解方法。通过对典型钢筋混凝土结构地下电缆排管的涡流场和温度场的数值分析,得到了典型钢筋混凝土结构地下电缆排管中金属构件的涡流分布,整个场域的温度场分布和谐态工况下的电缆线芯的温度;并据此提出了玻璃纤维代替传统钢筋的解决方案,对比分析了两种结构电缆排管的技术特点和经济性能。数值分析结果表明,使用玻璃纤维筋电缆排管的替代方案在能够降低涡流损耗的同时具有更好的经济效益。

Analysis of the eddy current loss and economy study in underground cable duct

In order to solve the issue of the electrical energy loss which is generated by the eddy current in traditional underground steel rein-forced duct model, a finite element model and method was proposed to analyze the eddy current field and temperature field in the complex en-vironment underground model and a scheme of using the glass fiber reinforced polymer ( GFRP) instead of the steel in the underground duct was proposed. Moreover, the three-dimension eddy current-temperature coupled field was computed by adopting a fast convergence, high ac-curacy mesh technique and an iteration solver for coupled multi-physics field;The eddy current distribution of the metal component, tempera-ture field distribution of the whole model were obtained;also the temperature of the cable cores under a harmonic current condition was ana-lyzed. The technical and economic performances of the traditional and proposed model were compared. The results indicate that the scheme of using GFRP instead of steel can reduce the loss, and possess better economic performance at the same time.