导线全面工频起晕电压测量新方法

New Method for Measuring Comprehensive Voltage Corona Onset Voltage of Wire

电晕放电会带来诸多危害,起始电晕电压的测量对于改进电气设备绝缘结构,提高起晕电压具有重要的意义,为此提出了一种测量导线起始电晕电压的新方法,即在导线附近安装非接触式电压传感器。导线发生电晕放电时电极表面出现的电离层改变了传感器分压比,因此利用分压比导数最大值可确定起始电晕电压。在介绍传感器测量的基本原理并通过工频试验验证传感器的测量精度后根据电晕套理论设计工频起晕试验,借助光子数切线法进行了对比研究。结果表明传感器可以准确测量导线全面起晕电压值,且通过传感器分压比的变化可以描述工频电晕的伏库特性。该方法简单便捷,易于实现,适合进行电晕试验研究。

It is important to measure corona onset voltage.We put forward a new measurement method of AC corona onset voltage,namely,installing a non-contact voltage sensor by the wire.When corona discharge occurs on the surface of the wire,ionosphere of line surface changes the sensor ratio,and changes of the sensor ratio can be used to measure corona discharge and corona onset voltage,thus a sensor model is established.The results of power frequency voltage tests indicate that the sensor has good precision.According to corona layer model theory,AC onset corona experiment is designed,and comparison with the photons tangent method indicates that the method can accurately measure the comprehensive corona onset voltage value.Analysis of AC experimental data shows that changes of sensor ratio can describe frequency corona characteristics.The method is simple and convenient,easy to realize,suitable for the engineering application and corona experimental studies.