基于电场的快速暂态过电压测量

Measurement of VFTO Based on Electric Field Sensor

提出了一种基于电场的VFTO测量方法,以实现气体绝缘变电站(Gas Insulated Substations GIS)开关操作引起的快速暂态过电压(Very Fast Transient Overvoltage VFTO)的测量。通过MEMS电场传感器测量GIS母线周围的电场,进行大量试验确定电场强度与母线电压的线性关系,并对传感器进行标定,实现VFTO的测量。从理论上对GIS变电站不同负载的VFTO建模并进行仿真数值计算;使用扫频法、方波响应法对电场传感器的响应特征进行了测试,高频截止频率>134 MHz;在实验室内进行了高幅值电压测量实验,在云南电网公司超高压试验研究基地进行GIS变电站现场VFTO测量实验,结果表明利用电场传感器能够进行快速暂态过电压的测量。

A measurement system based on electric field sensor was proposed, which is used to achieve the measure- ment of very fast transient overvoltage （VFTO） caused by switching operation of gas insulated substations （ GIS ）. Used the miniature electric field sensor to measure electric field of GIS bus bar, calculated the linear relationship between electric field intensity and the voltage of bas bar according to experiments for hundreds times, calibrated the sensor, finished the measurement of VFTO. Firstly, analyzed the VFTO waveform characteristics and the requirements of measurement system;then, made VFFO modeling of different loads on the GIS;tested the response characteristics of the sensor which has the high-frequency cut-off frequency higher than 134 MHz ;test the high am- plitude of voltage measurements in the laboratory, finally the measurement system was applied in the ultra-high volt- age test base of Yunnan power grid electric power research institute and measured for hundreds times, indicating the reliability of measurement of VFTO on electric field sensor.