220kV GIS中断路器关合空载变压器所产生VFTO辐射电场的测量与波形特征分析  

Measurement and Analysis of the Transient Radiation Electric Field Excited by the Breaker When Closing the Unloaded Transformer in GIS

作　　者：孔旭[1] 郭飞[1] 梁涛[1] 陈宇浩[1] 刘浩军[2] 吴旭涛[3] 王绍飞[1] 李启[1] 谢彦召[1] 

机构地区：[1]电力设备电气绝缘国家重点实验室(西安交通大学),陕西省西安市710049 [2]西安高压电器研究院有限责任公司,陕西省西安市710077 [3]国网宁夏电力公司电力科学研究院,宁夏回族自治区银川市750001

出　　处：《中国电机工程学报》2016年第18期5087-5093,5134,共7页Proceedings of the CSEE

摘　　要：为研究变电站中开关动作所产生瞬态辐射场的波形特征,利用变电站停电检修的机会对220k V GIS中三相断路器操作所产生的VFTO辐射电场进行了测量与分析。首先针对变电站内复杂的电磁环境,研制了一套宽频带、抗电磁干扰能力强且传输距离远的光纤电场测量系统;然后选取了数个具有代表意义的测点,对断路器闭合空载变压器时所产生的VFTO辐射电场进行了测量;取得测量结果后,分别从时域和频域进行了波形特征与分布规律的分析。经分析可知:断路器对空载变压器的闭合操作可以在变电站中产生VFTO辐射场,脉冲电场的幅值可达7k V/m,前沿可达5ns,前沿陡度可达1.2(k V/m)/ns,该辐射场对工作在GIS中的电子设备具有潜在的威胁,因此需要研究VFTO辐射场的波形特征。研究结果表明:VFTO辐射电场一般为间隔数ms的脉冲群,每个脉冲为振荡衰减波且具有多个特征频率,按照不同特征频率的波形成分衰减速度的不同,可以将脉冲在时域上分为三个时期。In order to study the waveform characteristics of transient electromagnetic field excited by operation of switches in substations, this paper measured and analyzed the radiated electric field（E-field） during the very fast transient over-voltage（VFTO） progress in a 220 k V gas insulated substation（GIS）. The measured VFTO radiation E-field was excited by a three phase circuit breaker when closing the no-load transformer during the power-off maintenance of the GIS. First, an electro-optical E-field measurement system was developed and fabricated. This measurement system had many advantages, such as wide-band response, anti-interference and long transmission distance, compared with traditional E-field measurement method. Then three representative measuring points in the 220 k V GIS are chosen and the corresponding VFTO radiation E-field is measured. The measuring result is analyzed both in time and frequency domain. The measuring result shows that radiated electromagnetic field can be generated when the breaker close the no-load transformer. The highest amplitude of the radiated E-field can be 7k V/m, the fastest rise time can be 5ns, and the slope of the E-field can reach 1.2（k V/m）/ns. This kind of transient E-field can threaten the normal operation of the electric devices around the GIS. So, it is important to study the waveform characteristics of the VFTO radiation E-field. It can be concluded that VFTO radiation E-field is a group of pulses with millisecond intervals. Each pulse oscillates and attenuates with the time and has many characteristic frequencies. Furthermore, each pulse can be divided into three periods in time domain according to the different attenuation rate of different characteristic frequencies.

关 键 词：GIS 光纤 电小天线 VFTO 辐射电场 测量 

分 类 号：TM835.4[电气工程—高电压与绝缘技术]