气压和污秽不均匀度对染污绝缘子泄漏电流的影响

Influence of Air Pressure and Non-uniform Pollution on the Leakage Current of Insulator

泄漏电流信号中包含了丰富的能够体现绝缘子运行状态的信息量。为此,以XP-70型瓷绝缘子为研究对象,在重庆大学输配电装备及系统安全与新技术国家重点实验室的人工雾室里进行了大量的交流人工污秽试验,分别研究了3种盐密、4种气压和5种不均匀度对绝缘子泄漏电流幅值的影响。试验结果表明:绝缘子整体平均盐密与上下表面污秽分布不均匀度和气压三者对绝缘子泄漏电流幅值的影响是相互独立的,泄漏电流幅值随着盐密的增加和气压的降低而均呈上升趋势,并且随着绝缘子上下表面污秽分布不均匀度的减小而呈下降趋势。还主要分析了绝缘子上下表面污秽分布不均匀度和气压对绝缘子泄漏电流幅值的影响机理。最后,利用最小二乘原理对试验结果进行拟合,得到了考虑盐密(ρESDD)、不均匀度(K)和气压(p)后的泄漏电流幅值的表达式,利用表达式可以估计绝缘子表面的污秽程度和分布特点。研究结果对于建立基于泄漏电流表征线路绝缘子的运行状态系统具有一定的参考价值。

Because signal of leakage current is rich in messages which can suggest the running state of the insulator,we experimentally researched AC artificial pollution of single XP-70 insulator in the artificial fog chamber in our Laboratory,and investigated the effects of three kinds of equivalent salt deposit density（ρESDD）,four kinds of air pressure（p） and five kinds of nonuniforminty（K） on the magnitude of leakage current.The experimental results show that the magnitude of leakage current of the insulator increases with the increase of the equivalent salt deposit density and the decrease of the air pressure,respectively,while decreases with the decrease of the non-uniformity.And their effects on the magnitude of leakage current of the insulator are independent each other.Moreover,we analyzed the mechanisms of the effects of non-uniform pollution distribution and air pressure on the magnitude of leakage current,and fitted the relation equations of ρESDD,K and p versus the magnitude of leakage current based on the principle of least square respectively,which could be used to estimate the polluted degree and pollution distribution of the surface of insulator.The results will be of great value for providing technical references to establish the system of the running condition of line insulators based on leakage current.