耦合因素对特高压交流同塔双回线路不平衡度的影响分析及相序优化  

Influences of coupling factors on imbalance of dual UHVAC transmission lines installed on same tower and optimization of phase sequence arrangement

作　　者：张龙伟[1] 吴广宁[1] 朱军[1] 吴静文[1] 石超群[1] 范建斌[2] 

机构地区：[1]西南交通大学电气工程学院,四川成都610031 [2]中国电力科学研究院,北京100192

出　　处：《电力自动化设备》2014年第7期124-128,共5页Electric Power Automation Equipment

基　　金：国家电网公司科技项目(2011-WG-4)~~

摘　　要：针对特高压同塔输电线路之间更强的电磁耦合作用加剧了电流不平衡度的问题,利用PSCAD/EMTDC软件建立了特高压交流同塔双回输电线路模型,分析了输电线路之间的电磁耦合作用以及架设耦合地线对电流不平衡度的影响,确定了线路导线的最优排列方式。分析结果表明:当一回线路处于重载而另一回线路处于轻载情况时电流不平衡度较大,当双回线路同时处于重载情况时电流不平衡度较小;当交流线路呈逆相序排列时,不平衡度处于较低水平;架设耦合地线时,穿越负序不平衡度和穿越零序不平衡度增加,而环流负序不平衡度和环流零序不平衡度减小;耦合地线横向位置对电流不平衡度影响较大,其架设高度对电流不平衡度影响较小。Aiming at the intense current imbalance caused by the stronger electromagnetic coupling between UHV transmission lines installed on the same tower,a corresponding model is established with PSCAD/ EMTDC for analyzing the influences of the electromagnetic coupling between transmission lines and the installed coupling ground wire on the current imbalance and determining the optimal phase sequence arrangement. The analytical results show that,the imbalance is bigger when one is heavily loaded while another one is slightly loaded;it is smaller when both lines are heavily loaded;it is smaller when AC lines are arranged in reverse phase sequence;when the coupling ground wire is installed,the imbalances of through negative-sequence and through zero-sequence increase while those of circulating negative-sequence and circulating zero-sequence decrease;the influence of the transverse position of coupling ground wire on the current imbalance is bigger while that of its height is smaller.

关 键 词：特高压输电 交流输电 同塔双回线路 不平衡度 电磁耦合 耦合地线 相序 模型 

分 类 号：TM721.2[电气工程—电力系统及自动化] TM723