基于EMTP的电能表雷电浪涌过电压防护分析  

Analysis of Protection Against Lightning Surge on the Watt-Hour Meter Based on EMTP

作　　者：李霖 曹彤 荆臻 LI Lin;CAO Tong;JING Zhen(State Grid Shandong Electric Power Research Institute,Jinan 250002,China)

机构地区：[1]国网山东省电力公司电力科学研究院,济南250002

出　　处：《电瓷避雷器》2018年第6期64-68,共5页Insulators and Surge Arresters

摘　　要：随着电子式电能表的广泛应用,其受到的雷害威胁日益严重,迫切需要分析电能表雷电浪涌过电压以对其进行合理防护。利用EMTP软件建立简化的配电系统模型,计算电能表遭受的雷电浪涌过电压,讨论配电避雷器安装方式对电能表终端浪涌过电压的影响,研究电能表前端安装SPD的防护效果,最后分析柱上变压器距电能表不同距离和不同SPD接地电阻下电能表过电压。研究结果表明:流过电能表的电流和电能表的对地过电压波形均呈现较为明显的振荡,且波头时间较短。电能表的对地过电压幅值较高,极易超过其冲击耐受电压。对地过电压幅值随着避雷器安装密度的增加而降低,对应的过电压幅值累积概率分布曲线也整体左移。电能表的对地过电压随着柱上变压器距电能表距离的增加而增大。电能表前端安装SPD后能够有效降低浪涌过电压,但需要尽可能降低SPD接地电阻。With wide application of electronic watt-hour meter,it is faced with increasingly serious lightning disasters,which makes it a pressing need to analyze lightning surge on the watt-hour meter in order to take rational preventive measures. A simplified model of distribution power system was established in EMTP to calculate lightning surge overvoltage of the watt-hour meter. Influence of installation density of distribution arresters and front-end SPD on voltage-to-ground of the watt-hour meter was presented.Finally,voltage-to-ground of the watt-hour meter under with different line length and load types were also analyzed. Research results show that: wire current and voltage-to-ground of the watt-hour meter show obvious oscillations and voltage-to-ground may exceed impulse withstand voltage of the watt-hour meter easily. The whole curve of cumulative-probability distribution of overvoltage moves to the left with the increasing of installation density of distribution arresters. Voltage-to-ground of the watt-hour meter increases with the increasing of line length as well as ground resistance of SPD. Overvoltage of the watt-hour meter can be inhibited effectively when front-end SPD is installed,but it is essential to reduce the ground resistance as low as possible.

关 键 词：电子式电能表 配电线路 雷电浪涌 EMTP 

分 类 号：TM862[电气工程—高电压与绝缘技术]