摘要
±660 kV高压直流输电线路是世界上首条该电压等级的线路,大跨越段是耐雷性能比较薄弱的部分,因此有必要对其耐雷特性进行更加详细的研究。笔者利用改进的EGM,考虑雷电对导线、地线和大地三者击距的差异、风偏影响、地形影响和导线工作电压影响等,对中国±660 kV高压直流输电线路的大跨越段进行了绕击耐雷性能分析。仿真结果表明,随着地面倾角的增加,导线工作电压对绕击跳闸率的影响减小,但不容忽视,因此计算中必须考虑导线工作电压。随着风速和地面倾角的增大,绕击跳闸率呈加速度增长。当地面倾角大于20°,风速大于20 m/s时,大跨越线路的绕击跳闸率超过指标要求0.1次/(100 km.a)。鉴于大跨越线路大都处于地理和气候条件恶劣的地方,因而要加强线路的雷电防护措施,从而提高大跨越线路的绕击耐雷性能。
±660 kV HVDC transmission line is the world＇s first line in this voltage grade. The lightning protection performance of long span line is the relatively weaker part in the whole transmission line. So it is necessary to carry out a more detailed investigation. In this paper, an improved EGM is proposed to evaluate the shielding failure tripout rate of ±660 kV HVDC transmission line. The striking distances to conductors, shield wires and ground are differentiated. Furthermore ,the influences of ground obliquity, wind deflection and operating voltage of phase conductors are taken into account. The simulation results show that the impacts of conductor voltage to the shielding failure trip-out rate decrease with the increasing ground obliquity. But the impacts should not be ignored and the conductor should be considered. Also, the shielding failure rate accelerates with the increase of the ground obliquity and the wind speed. When the ground obliquity is more than 20° and the wind speed is more than 20 m/s,the shielding trip-out failure rate of long span transmission line exceeds the indicator 0.1 times/（100km.a）. Furthermore, given the long span transmission lines generally lie in bad geographical and climatic conditions, thus it is critical to take effective lightning protection measures to improve the shielding failure lightning protection performance.
出处
《高压电器》
CAS
CSCD
北大核心
2013年第4期54-59,共6页
High Voltage Apparatus
基金
山东电力集团公司电力科学研究院基金项目(KY2013-10)~~
