摘要
随着气体绝缘全封闭组合电器(GIS)的广泛使用,由隔离开关和断路器操作引起的快速暂态过电压(VFTO)带来的危害越加明显。以某典型500 kV GIS智能变电站为计算原型,研究500 kV GIS变电站VFTO对电子式互感器的电磁骚扰。以噪声源和传播路径为基础,通过建立噪声耦合近似模型,实现对电子式互感器干扰信息的定性分析研究。通过分析发现,互感器耦合路径上的耦合电容C_L和C_N越小,VFTO噪声耦合效率越低,VFTO对电子式互感器的噪声影响也越小。研究结果表明,低频段通过修正C_L和C_N实现对电磁干扰的抑制,高频段采用滤波和屏蔽最为有效。通过现场实测证实,未安装防护装置情况下,测得数字采集卡输入端耦合VFTO最高幅值达到9.9 kV,采用电磁兼容综合防护措施后,VFTO最高幅值为0.61 V。
With the widespread use of the gas insulated switchgear（ GIS）,the harm of very fast transient overvoltage（ VFTO） caused by the disconnecting switch（ DS） and the circuit breaker（ CB） operation becomes increasingly obvious. One 500 k V GIS smart substation is used as a prototype to study the impact of VFTO electromagnetic interference on electronic transformers in 500 k V GIS substation. Base on the noise source and the transmission pathway,a noise coupling model has been set up in order to analyze the VFTO electromagnetic interference on electronic transformers qualitatively. It has been found that the decrease of the coupling capacity of transformer,i. e. CL,and CN,will contribute to the low noise coupling effect of VFTO. The conclusion shows that the most effective method for interference reduction is to revise CL,CNin the low frequency and add low band filter and shielding box in the high frequency. It has been proved by experimental data that the VFTO maximum amplitude is reduced from 9. 9 k V to 0. 61 V by using this method.
出处
《电工技术学报》
EI
CSCD
北大核心
2016年第1期85-90,共6页
Transactions of China Electrotechnical Society
关键词
VFTO
电子式互感器
噪声耦合模型
干扰抑制
Very fast transient overvoltage
electronic transformer
noise coupling model
interference reduction
