采用空间电荷分析的导线交流起晕电压测量

Measurement of AC Corona Onset Voltage Conductor by Space Charge Analysis

导线电晕现象是导线表面电场强度高于周围介质电气强度所产生的电气现象,与导线的空间结构、电压、大气环境等因素有关。导线起晕电压的准确测量可以优化导线及其电场结构,提高其电气强度,减小电晕损耗及干扰。基于分析电晕产生空间电荷的过程及其对电场的畸变作用,提出导线附近空间电荷的检测方法。通过导线与感应电极间杂散电容与取样电容分压的方式,分析交流电压下电晕空间电荷影响感应电压波形的规律。采用特征量提取法分析计算导线起晕电压。搭建导线交流电晕放电模拟实验平台,验证了特征量提取测量起晕电压方法的有效性。

Corona phenomenon of conductor is the electrical phenomenon that the electric field intensity of conductor surface is higher than that of surrounding medium,which is related to the spatial structure of conductor,voltage,atmospheric environment and other factors.The accurate measurement of the corona onset voltage can optimize the structure of the conductor and its electric field,reduce the corona loss,and improve the electrical strength.Based on the analysis of the process of space charge generated by corona and its distortion effect on electric field,a method of space charge detection around the conductor was proposed.By the voltage division mode of the stray capacitance between the conductor and the sensing electrode and the sampling capacitor,the rule that the corona space charge affects the induced voltage waveform under AC voltage was analyzed.The corona onset voltage of conductor was calculated by the method of feature extraction.The simulation experiment platform of conductor AC corona discharge was built to verify the validity of this method.