土壤温度特性试验及其对圆环型直流接地极发热影响分析  

Analysis on the Temperature Characteristic of Soil and Its Influence on the Cirque Grounding Electrode Heating

作　　者：袁涛[1] 骆玲[1] 杨庆[1] 司马文霞[1] 王建东 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044 [2]三亚供电局生产技术部,海南省三亚市572000

出　　处：《中国电机工程学报》2013年第1期188-195,共8页Proceedings of the CSEE

基　　金：国家创新研究群体基金(51021005);国家重点基础研究发展计划(973项目)(2009CB724504);国家自然科学基金(51107153)~~

摘　　要：为了更全面的分析直流输电接地极的发热过程,优化接地极设计,针对2种不同质地的土壤样品进行了温升模拟试验研究,建立了土壤含水量、热参数以及土壤电阻率的温度特性。同时,结合试验结果,采用有限元方法,建立了电热动态耦合模型,仿真分析了单圆环、双圆环型接地极在直流输电系统长时间单极运行时的温升情况,与传统模型中未考虑土壤温升效应的仿真结果进行了对比。试验及仿真结果表明:土壤参数会随温度而变化,从而进一步影响接地极的发热升温,而温升过高可能导致接地极不能正常工作。因此,结合土壤温度特性对接地极进行设计,能更大程度的保证接地系统的安全运行。In order to have a comprehensive analysis of the grounding electrode heating process and optimize the electrode design, this paper selects two different textures of soil to have a temperature simulation experiment. The temperature characteristic of soil water content, soil thermal parameters and soil resistivity obtained from the experiment results. According to the soil temperature characteristic, the finite element method and the electric-thermal dynamical coupling model were integrated to simulate the temperature rise of the cirque grounding electrode in the monopole ground return mode in a long duration, and then compare with the calculation method without considering the effect of soil temperature rise. The results of experiment and simulation indicate that： soil parameters will vary with the temperature rise, lead to grounding electrode have further heating, and the worse temperature rise can result in abnormal operating of the grounding electrode. Therefore, combine soil temperature characteristic with the grounding electrode design can ensure more safety operation of the grounding system.

关 键 词：土壤热参数 温度特性 电热耦合 圆环型接地极 接地极温升 

分 类 号：TM86[电气工程—高电压与绝缘技术]