330 kV同塔双回输电线路下平行运行的380 V线路感应电压电流仿真计算

Induced voltage and current simulation of 380 V lineparallel operating under 330 kV double-circuit transmission lines

在西北经济走廊地区,为了最大程度的节省占地面积,提高经济效益,高压输电线路下存在低穿且并列运行的低压配电线路。当低压线路进行停电检修时,由于同塔多回高压输电线路的静电与电磁耦合产生的感应电压,感应电流会危害到检修人员的安全。因此,以西北地区罗山—灵州330 kV输电线路正常运行时的情况为例,利用电磁仿真软件ATP-EMTP搭建模型,从线路长度、电流大小、呼称高度以及偏离杆塔中心的距离4个方面分析对比其平行运行的380 V线路上的感应电压、感应电流的变化情况,计算不同作业方式下流过人体电流的数值。研究结果表明:静电感应电压主要与偏离杆塔中心距离和呼称高度有关,静电感应电流主要受低穿并列运行线路长度和呼称高度影响;电磁感应电压电流与低穿并列运行线路的长度、运行电流的大小、杆塔偏离中心距离这3个因素都有关;在检修作业时,综合考虑各项人体生理效应推荐值,建议选取方式2进行安全作业。

In the Northwest Economic Corridor region,the distribution lines with the low voltage ride through is built and parallel operates under high voltage lines in order to save the land occupation and improve the economic benefit.However,during the outage maintenance process of the low voltage line,the induction voltage and current generated by electrostatic effect and electromagnetic coupling of the multi-circuit high-voltage transmission lines may threaten the safety of maintenance personnel.On this background,the normal operation of Luoshan-Lingzhou 330kV transmission line in Northwest China is taken as an example and an ATP-EMTP simulation model is built in this paper.Then the variation of induction voltage and current on 380V line is compared and analyzed in the aspects of transmission line length,current magnitude,nominal height and the distance from the tower center.The magnitude of the current through human body is also calculated in different maintenance modes.The results show that the electrostatic induction voltage is mainly related to the nominal height of high voltage tower and the distance from the tower center.The electrostatic induction current is mainly affected by the nominal height of high voltage tower and the length of low voltage line.The electromagnetic induction voltage and current are influenced by the length of low voltage line,the magnitude of the operating current and the distance from the tower center.Comprehensively considered various recommended values of human physiological effects,the maintenance method of adding security grounding line is suggested to ensure the safety operation.