雷电流波形参数检测视角下的±800kV直流输电线路反击电磁暂态分析  

Electromagnetic transient analysis of back flashover in ±800 kV DC transmission line to acquire lightning parameters

作　　者：束洪春[1] 曹璞璘[1] 张广斌[2] 张斌[1] 杨毅[1] 刘可真[2] 

机构地区：[1]昆明理工大学电力工程学院,云南昆明650051 [2]哈尔滨工业大学电气工程及其自动化学院,黑龙江哈尔滨150001

出　　处：《电力自动化设备》2011年第9期1-9,共9页Electric Power Automation Equipment

基　　金：国家自然科学基金资助项目(50977039;50847043;90610024;50467002;50347026)~~

摘　　要：从获取雷电流波形参数的角度出发,研究雷击特高压直流输电线路的避雷线档距中央、杆塔外撑角和塔顶时传输系统的行波响应,依据分布参数电路理论分析注入传输系统的雷电流在各电流通道中的电流行波波形。当雷击避雷线或避雷线与杆塔外撑角连接处未造成闪络时,避雷线与杆塔外撑角连接处的暂态电流含有大部分雷电流上升沿响应;当雷击塔顶未闪络时,大部分雷电流经杆塔直接流入大地。发生雷击闪络时,传输系统受到雷电流激励和闪络故障附加激励先后2次冲击,其波过程可视为2次冲击在传输系统引起的行波暂态响应。绝缘子闪络时,雷电流上升沿行波已经离开绝缘子传播,绝缘子闪络电流波形上升沿与注入传输系统的雷电流上升沿相差甚远。当雷击避雷线或杆塔外撑角连接处造成闪络时,杆塔外撑角连接处的暂态电流包含了绝大部分雷电流上升沿响应;在雷击塔顶造成闪络情况下,雷电流上升沿主要经杆塔流入大地,其他电流行波通道所含雷电流上升沿响应较少。无论雷击是否造成闪络,绝缘子闪络电流均不含有雷电流上升沿信息,故为了获取雷电流波形参数,需检测雷击点附近避雷线或避雷线与杆塔外撑角连接处的电流行波。In order to acquire the lightning parameters,the current responses are analyzed for different lightning striking cases：the shielding wire,the connection between shielding wire and tower,and the tower. The distributed resistance circuittheory is used to explain the transient currents in different channels. When lightning strikes the shielding wire or the connection between tower and shielding wire without flashover,the transient current of connection contains most of uprising lightning current. When lightning strikes the tower without flashover,most lightning current passes directly through tower to ground. When the lightning causes flashover,the power system is affected successively by lightning impulse and flashover impulse,and the wave process can be taken as the traveling wave transient response. Since the uprising lightning current has traveled away from the insulator when the flashover happens,its transient current is quite different from that in system. When lightning strikes the shielding wire or the connection between shielding wire and tower with flashover,its transient current contains most of the uprising lightning current. When lighting strikes the tower with tlashover,most of the uprising lightning current passes directly through tower to ground and other channels of transient current contain few uprising lightning current. The transient current of insulator contains no uprising lightning current in both cases. In order to acquire the lightning parameters ,the current traveling waves of the shielding wire or the connection between shielding wire and tower should be detected.

关 键 词：雷击 雷击避雷线档距中央 雷击杆塔外撑角 雷击塔顶 雷电流上升沿 直流输电 内络 绝 缘子:暂态分析 

分 类 号：TM727[电气工程—电力系统及自动化]