基于SVC的变电站中电磁辐射测试分析

Measurement and analysis of radiated emissions generated by SVC-based substations

安装新型静态无功补偿器(SVC)的变电站,其电磁兼容环境需要重新评估,以提出足够的电磁抗扰性措施。应用电磁场天线和光纤传输等技术,对4个不同类型的SVC变电站进行了现场测试和分析,结果表明SVC的高频电磁辐射集中在10kHz至3.5MHz,最大辐射强度为磁场0.87A/m和电场114V/m。将测量数据与当前国际电工委员会的IEC61000-4系列电磁兼容标准进行了相关比较,针对基于SVC的电磁辐射干扰提出两项抗扰性试验的具体改进建议。初步理论分析指出,晶闸管阀的开关特性和SVC结构的杂散参数是产生高频辐射干扰(谐波以上)的主要原因。

The electromagnetic compatible environments in substations installed with new SVC devices need to be re-evaluated, to provide sufficient immunity measures. Antennas and optical fibre transmission techniques were used for on-site measurements and data analysis at four different SVC-based substations. The high frequency electromagnetic emissions produced by the SVCs were mainly from 10 kHz to 3.5 MHz, with maximum emission amplitudes of 0.87 A/m and 114 V/m recorded for the H - and E -fields. The results were correlated to the present EMC standards IEC 61000-4 series, with two recommendations for changes in the immunity tests specifically for SVC-based emissions. A preliminary theoretical analysis indicats that the thyristor valve characteristics is the principal contributor to the high frequency radiated interference.