500kV变电站保护小间接地方式的研究

Study on grounding mode of relay cells of ?0 kV substations

利用矩量法(ＭｏＭ)和快速傅立叶变换(ＦＦＴ),对一个 ５００ｋＶ变电站遭受雷击时接地网的暂态地电位升进行了数值计算。对保护小间内一些关键点的暂态地电位升进行了分析研究。分析结果表明,保护小间内应该铺设接地网,并且保护小间的接地网与主地网应采用四点连接,连接点应该在保护小间的四个角上。

It is very important to predict the distribution of the potential in the relay cell when the lightning strikes at the 500 kV substation. The paper calculates the transient grounding potential rise of the grounding grid of the 500 kV substation stroke by lightning based on the method of moment (MoM) and the fast Fourier transform (FFT). The transient grounding potential rise of some key points is analyzed in the grounding grid of the relay cell. The result indicates that the grounding grid should be made in the relay cell. There are four connection points between the main grounding grid of the substation and the grounding grid of the relay cell. The four connection points should be at the corners of the relay cell.