牵引负荷对介质损耗因数测量的干扰分析

对电气化铁路牵引负荷的冲击特性及其对高压设备绝缘老化的检测系统的影响进行分析,在对负荷进行定性讨论的基础上探讨了冲击性电流增量的幅值对电容型设备测量参数介质损耗因数的影响,以三相综合电流为基础,通过向量分析揭示了负荷电流变化对高压套管监测电流的干扰,建立了针对高压套管的简化冲击干扰模型。分析结果表明:受冲击电流幅值的影响,高压套管介质损耗因数变化呈现一定的规律性,但由于初始综合电流不同,不同组套管会具有不同的变化规律。根据现场测试,以湖东牵引变电所为例,对变压器高压套管特征数据在线采集、分析,验证该干扰模型。

Analysis of Interference to Measurement of Dielectric Loss Factor Caused by Traction Load

The traction’s load of electrified railway influence the accuracy of the HV equipment insulation aging detection system online and on-site because of the characteristic of its impact. On the basis of three-phase comprehensive current theory, it mainly discussed the influence to the measuring parameters of dielectric loss factor by the impact current. According to the system’s internal interference analysis, establish impact interference model for transformer HV bushing. Results show that the dielectric loss measure of HV bushing will suffer the influence of impact current. When impact load exist, the dielectric loss factor measured will decrease, otherwise, it will increase. Through the on-site data measured in HuDong traction substation, validated it. But different group of three-phase HV equipment may follow different impact interference laws, due to the different initial comprehensive current. It depends on the actual situation.