摘要
笔者首先根据电磁场理论分析雷击大地时在导线上产生的感应过电压分布情况。其次,通过引入击距的概念计算各种雷电流幅值在导线上产生的感应雷过电压最大值,并得出造成感应雷过电压的最小雷电流幅值。结合以上两者分析,提出在绝缘子串发生闪络之前,附近避雷器率先动作以达到防止绝缘闪络的目的,因此根据感应雷过电压分布情况和避雷器动作条件求取避雷器的感应雷过电压保护范围,得出避雷器感应雷保护范围与雷电流幅值存在正相关性的结论。最后,根据计算实例和实际情况得出不同避雷器安装密度对感应雷和直击雷的防护效果,为电力部门对10 kV配电线路避雷器的配置提供依据。
Based on the electromagnetic field theory, this paper analyses the distribution of induced overvoltage in wire which is caused by lightning striking to ground; then calculates the maximum of induction overvohage caused by kinds of current amplitude in wire by introducing the concept of ＇striking distance＇ and obtains the minimum of lightning current amplitude creating the induced overvoltage. Combining with both analyses above, this paper puts forward that before the insulator string flash over happens, lightning arresters nearby takes action to prevent the insulation flash over. Therefore according to the distribution of induction lightning overvoltage and the condition of movement of lightning arrester, the induction overvoltage protection range of lightning arrester is calculated, and it is a concluded that there is a positive correlation between the current amplitude and induction lightning protection scope of the lightning arrester. At last, based on the calculation examples and actual situation, the protective effect of different lightning arrester installation density on the induction lightning and direct striking lightning is gotten, which provides the basis for configuration of 10 kV distribution line arrester.
出处
《高压电器》
CAS
CSCD
北大核心
2013年第4期122-127,共6页
High Voltage Apparatus
关键词
避雷器
保护范围
感应雷
电磁场
动作电压
安装密度
最大感应雷过电压
击距
lightning arrester
protective range
induction stroke
electromagnetic field
operating voltage
installation density
the maximum of induced overvoltage
striking distance
