复合绝缘子直流冰闪试验方法的比较

国内外的运行经验和研究表明,由覆冰引起的输电线路绝缘子串绝缘特性下降是导致电网事故的重要原因之一。绝缘子覆冰试验目前尚无统一的标准,研究绝缘子覆冰试验方法有重要的意义。因此以FXBW-±800/530型短样、FXBW-110/100型两种复合绝缘子为试品,在人工气候室研究了试验方法对覆冰复合绝缘子直流冰闪特性的影响,并比较分析了不同试验方法的差异。结果表明:试验方法对覆冰复合绝缘子的冰闪电压有明显的影响,采用不同的试验方法获得的试验结果有差异。复合绝缘子在相同覆冰水电导率、覆冰程度和覆冰状态以及相同的试验条件下,采用平均闪络法获得的平均闪络电压Uav最高,采用最恒压升降法获得的50%闪络电压U50%其次,采用U型曲线法获得的最低闪络电压Uf,min次之,采用最大耐受法获得的最大耐受电压Uws最低。不同的试验方法获得的试验结果存在内在联系,可以根据试验的具体情况,选择适当的试验方法。

Comparisim of DC Flashover Test Methods for Ice-covered Composite Insulators

For lack of uniform standards of icing test for insulator,the study on the methods for icing insulator test is of significance.Taking two types of composite insulator,short-like FXBW-±800/530 and FXBW-110/100,as examples,we studied the influence of various test method on flashover performance of insulator in the artificial climate chamber.The results show that,the impact of various test method on flashover performance of composite insulator is remarkable,and the experimental results obtained by using different test methods are discrepant.The average flashover voltage(Uav) obtained by using average flashover voltage method is highest,the 50% withstand voltage(U50%) obtained by using up and down method is the second,the lowest flashover voltage(Uf,min) obtained by using U-curve method is the third,and the maximum withstand voltage(Uws) obtained by the maximum withstand voltage method is the lowest.There is an intrinsic relationship among the test results obtained by various test methods.Therefore,the appropriate test method can be selected according to the specific testing circumstances.