环境因素对正直流架空导线起晕电压的影响  

Influence of Environmental Factors on Positive DC Corona Inception Voltage of Overhead Transmission Lines

作　　者：孟晓波[1,2] 卞星明[1,2] 赵雪松 曹晶[4] 杨迎建[4] 邬雄[4] 王黎明[1,2] 关志成[1,2] 

机构地区：[1]清华大学电机工程与应用电子技术系,北京100084 [2]清华大学深圳研究生院,深圳518055 [3]华北电网北京超高压公司,北京102401 [4]国网电力科学研究院,武汉430074

出　　处：《高电压技术》2010年第8期1916-1922,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2009CB724503);国家自然科学基金(50777033;50977048)~~

摘　　要：电晕放电是输电线路设计和运行中面临的重要问题之一。输电线路跨越高海拔地区,由于海拔高度升高、气压降低,将给输电线路的设计和运行带来很多特殊问题。同时,湿度和温度对输电线路导线电晕特性也有很大的影响。因此研究气压、湿度和温度对输电线路导线电晕特性、放电机理具有重要的学术意义和工程应用价值。利用气体放电理论建立导线电晕起始电压放电模型,系统地分析了气压、湿度、温度对导线电晕起始特性的影响。计算模型采用模拟电荷法计算空间电场分布,然后根据二次电子崩正离子数大于等于一次电子崩正离子数目的起晕电压判据计算出导线起晕电压。计算结果显示电晕起始电压随气压下降、温度升高而减小,主要原因是有效电离系数增大导致的电离区域的扩大;随湿度升高而减小,主要原因是高场强区域内碰撞电离能力的增强。The corona discharge effect is one of important problems in the design and operation of transmission lines. The transmission lines pass by the high altitude region with low air pressure, which brings many special problems to the design and operation of the transmission lines. Temperature and humidity also have obvious effects on the corona characteristics of the transmission lines. Consequently, it is significant to study the impact of air pressure, temperature and humidity on the corona characteristics and discharge mechanism of transmission lines. A computation mod el, which was established according to the gas discharge theory, was adopted to evaluate the corona inception voltage on conductors. The charge simulation method was introduced to the computation model to calculate the electric field intensity. Then the criterion of corona inception voltage, which considered whether the number of positive ions in the secondary avalanches was greater or equal to that in the primary avalanche, was used to calculate the corona inception voltage of conductors. The influences of air pressure, humidity and temperature on the corona inception voltage of conductors were analyzed systematically. The results show that, the corona inception voltage decreases as air pressure is lowered or temperature is raised. It is mainly due to the enlargement of ionization zone as a result of the increase of effective ionization coefficient. Simultaneously, the corona inception voltage decreases with humidity increasing for strengthening of collisional ionization intensity.

关 键 词：正直流电晕 起始电压 气压 湿度 温度 光滑导线 

分 类 号：TM851[电气工程—高电压与绝缘技术]