标称3MV快速暂态过电压测量用传感器研制  

Voltage Sensor Development for VFTO Measurement with Nominal Voltage of 3 MV

作　　者：张璐 齐卫东 黄国强 张乔根[2] 孙蕾[3] 赵亚林 

机构地区：[1]国网陕西省电力公司电力科学研究院,西安710054 [2]西安交通大学电气工程学院,西安710049 [3]中国水电顾问集团西北勘测设计研究院,西安710065

出　　处：《高电压技术》2016年第6期1811-1818,共8页High Voltage Engineering

基　　金：国家自然科学基金(51177132);国家电网公司科技项目(5226sx15001T)~~

摘　　要：快速暂态过电压(VFTO)对特高压气体绝缘开关设备(GIS)造成极大威胁,有必要研制一种能准确测量MV级纳秒脉冲电压的传感器,为VFTO下GIS绝缘特性研究提供准确的测量手段。采用电容分压器加积分器的方案,研制了一种锥形电压传感器。通过计算和实测,对传感器结构尺寸、积分电阻、积分电容和传输电缆长度等参数进行了优化。结果表明:锥形结构的电压传感器较平板结构电压传感器分压比更大,频带更宽。积分电阻值应与传输电缆波阻抗相匹配,积分电容的最优值与积分电阻值、传感器电容值及传输电缆长度有关,一般处于100~200 p F之间。为避免VFTO在传输过程中的折反射,传输电缆长度一般不超过20 cm。标定结果表明,锥形电压传感器响应时间可低至4.8 ns,分压比高达43 402,带宽为7.8 Hz^73 MHz,可满足对MV级VFTO信号的准确测量。Very fast transient overvoltage（VFTO） greatly threatens ultra-high voltage gas insulated switchgear（GIS）. To supply an accurate measurement method for insulation characteristic research of GIS under VFTO, it is necessary to develop a voltage sensor for measuring nanosecond impulse voltage with magnitude of several megavolts accurately. The scheme of capacitive voltage divider and integral implement was adopted, and a conical voltage sensor was developed. The structure size of sensor, value of integral resistance, integral capacitance, and length of transmission cable were optimized by calculation and measurement. The results indicate that the voltage ratio of conical sensor is higher than that of plane sensor, and the frequency band of conical sensor is wider than that of plane sensor. The integral resistance should match with the wave resistance of transmission cable, and the optimum value of integral capacitance is between 100 p F and 200 p F, which is related with integral resistance, capacitance of sensor and the length of transmission line. To avoid refraction and reflection of VFTO in the process of transmission, the length of transmission cable usually does not exceed 20 cm. The calibration results show that the response time of conical voltage sensor is shorter than 4.8 ns, the voltage ratio of the sensor can reach up to 43 402 and the frequency band is between 7.8 Hz to 73 MHz, which can meet the measurement requirements of VFTO with magnitude of several megavolts.

关 键 词：气体绝缘开关设备 快速暂态过电压 锥形电压传感器 积分电阻 积分电容 传输电缆 

分 类 号：TM595[电气工程—电器] TP212[自动化与计算机技术—检测技术与自动化装置]