【作者】 张智；

【导师】 司马文霞；

【作者基本信息】 重庆大学 ， 电气工程， 2013， 硕士

【摘要】 输电线路因雷击引起的事故给电力系统的安全运行带来了极大的考验，对国民经济的发展、人民的日常生活影响也非常大，最大限度的减少输电线路雷击事故一直是电力科技工作者所追求的。绝缘子串并联间隙是一种输电线路“疏导型”防雷保护装置，可以作为输电线路传统“堵塞型”防雷保护方式的有力补充。同时，并联间隙防雷保护装置安装方便、经济适用，具有广阔的应用前景。在本实验室已开展的并联间隙防雷保护性能研究的基础上，本文主要针对绝缘子串带并联间隙绝缘配合、并联间隙导弧性能和结构优化问题开展了深入的研究，对绝缘子串带并联间隙装置的理论研究和工程应用具有重要的学术价值和指导意义。以寻求我国输电线路绝缘子串合适的并联间隙距离为目标，本文在海拔高度为2100m的南方电网特高压工程技术（昆明）国家工程实验室，对220kV复合绝缘子（FXBW4–220/100）加装环形和棒形并联间隙、220kV瓷绝缘子（XP–70）加装棒形并联间隙，开展了标准雷电冲击闪络特性试验研究和标准操作冲击闪络特性试验研究。试验结果表明：相同间距下，复合绝缘子串带环形并联间隙的雷电和操作冲击50%闪络电压均较带棒形并联间隙稍高；瓷绝缘串带棒形并联间隙的雷电冲击50%闪络电压高于复合绝缘子串带棒形并联间隙。基于链式电弧模型，本论文建立了环形并联间隙电弧运动模型，仿真计算了不同短路电流水平下的电弧运动过程。电弧运动仿真结果还得到了燃弧试验结果的有效验证。此外，利用该模型分析了环形并联间隙电弧运动影响因素。结果表明：该环形并联间隙电弧运动仿真模型能够较为准确的反映电弧在间隙电极上的运动快慢和趋势。环形并联间隙带开口设计可以改善电极上短路电流分布，提高电弧疏导性能；电弧在环形并联间隙上的运动时间随短路电流的增大近似指数规律减小；环形并联间隙曲率半径越大，电弧疏导也越快。基于220kV绝缘子串并联间隙冲击闪络特性试验结果，本文分析了绝缘子串与并联间隙的绝缘配合情况，并建立输电线路雷击模型，计算加装并联间隙前后线路的雷击跳闸率，推荐了并联间隙间距。结果表明：220kV复合绝缘子加装环形并联间隙的间距为1744mm，加装棒形并联间隙的间距为1844mm，220kV瓷绝缘子加装棒形并联间隙的间距为1722mm。并联间隙装置能起到定位雷击闪络点，有效保护绝缘子的功能。同时，不过分提高线路雷击跳闸率，满足线路操作过电压要求。更多还原

【Abstract】 The transmission line accidents caused by lightning strikes bring about a great dealof trouble to safety operation of power system, and have a significant impact to thenational economy and the daily life of the people. Minimize transmission line lightningaccident rate has been the pursuit of the power of science and technology workers. Theparallel gap connected to both ends of the insulator string is a guiding type lightningprotection device for transmission line. It can serve as a strong complement totraditional transmission line lightning protection methods. The parallel gap lightningprotection device(PGLPD) is economical、easy to install and has broad applicationprospects. Based on the PGLPD lightning protection performance study that has beenconducted by our laboratory, this article is mainly for insulation coordination、arc-guiding performance of the PGLPD. It is of great significance for theoreticalresearch and instructing engineering applications of the PGLPD.Aim at determining the suitable distance of parallel gap for transmission lineinsulator in our country. The standard negative lightning impulse and standard positiveswitching impulse flashover characteristics experiments on220kV compositeinsulator(FXBW4–220/100) with ring shape and rod shape PGLPD and220kVporcelain insulator(XP–70) with rod shape PGLPD separately were carried out in theNational Engineering Laboratory (Kunming) for UHV Engineering Technology wherelocate at the2100altitude area. The results show that the lightning impulse50%flashover voltage and switching impulse50%flashover voltage of composite insulatorwith ring shape PGLPD is higher than the porcelain insulator with rod shape PGLPD;the lightning impulse50%flashover voltage of porcelain insulator with rod shapePGLPD is higher than the composite insulator with rod shape PGLPD when the distancebetween the electrodes is same or closed.Based on the chain arc model, this paper founded the arc movement simulationmodel applied to ring shape PGLPD. The arc movement process with differentshort-circuit current level was simulated. The simulation results were validated by thearc-burning experiment results. Using this model, the influence factors of arc movementon the ring shape PGLPD were analyzed. The results show that the arc movementsimulation model on the ring shape PGLPD can accurately reflect the speed and trendsof arc movement. The ring shape PGLPD with an opening design can improve short-circuit current distribution on the electrode, which raising the arc-guidingperformance. The arc movement time on the ring shape PGLPD approximatelyexponentially decreases with short-circuit current increasing. The larger radius of ringshape PGLPD is, the faster the arc moves.Based on the impulse flashover characteristics experiment results of220kVinsulators with PGLPD, the insulation coordination situation between insulator andPGLPD were analyzed in this paper. Founding the transmission lines lightning model,this paper calculated the lightning trip rate and recommended the distance of PGLPD.The results show that the PGLPD can play the role of locating lightning flashover pointand protect insulator effectively when220kV composite insulator with1744mm ringshape PGLPD or1844mm rod shape PGLPD and220kV porcelain insulator with1722mm rod shape PGLPD. Meanwhile, the transmission line lightning trip rate willnot rise too much and the distance between the electrodes meet the requirement ofswitching impulse voltage withstanding value for220kV transmission line in china.更多还原