硕论 乡村振兴背景下农村集体产权制度改革研究——以枣庄市台儿庄区为例 (5).docxVIP

摘 要 雷电灾害严重影响人们的正常生活，从设施损坏到发生大面积的停电事故，因此防雷电灾害依然是电力系统安全稳定运行的关键。据统计，雷击事故不仅会造成输电线路杆塔的单相闪络，甚至造成两回同跳的严重跳闸事故。 本文根据十堰山区的特殊地形与地貌﹑复杂线路结构等因素，采雷电事故频繁发生，当地电力系统的稳定受到严重威胁。在过去的五年中，该地区220kV线路多次发生雷击闪络事故，造成事故的原因多数为雷电所引起的杆塔反击跳闸，对十堰地区电力系统的安全稳定运行造成恶劣影响。本文对该地区的220kV两条输电线路发生的故障进行事故分析和事故复现，并对该地区的反击耐雷性能进行评估，采取差异化防雷为防雷准则，制定防雷策略，对减少该地区杆塔的跳闸率，提升电力系统的安全稳定运行有着参考意义。 本文对防雷评估过程中所做的工作包括输电线路杆塔上雷电感应电压的计算、雷电主要参数的详细分析、Bergeron算法的介绍以及电磁暂态软件EMTP中的典型模块进行详细阐述，为十堰地区的220kV输电线路反击事故的分析与建模提供了理论支撑。利用EMTP电磁暂态软件建立220kV单回与双回输电线路雷电反击模型，并以数据验证该模型的理论可靠性，用于计算输电线路的反击耐雷水平。分析了不同因素对220kV单、双回输电线路反击耐雷性能的影响规律。仿真结果表明，工频电压的相位直接决定了导线闪络的次序；影响杆塔反击耐雷水平最关键的因素是接地电阻的大小，根据试验数据得出同塔双回输电线路的接地电阻最好低于10Ω；平衡高绝缘也对杆塔反击耐雷水平有明显提升，而采用不平衡绝缘方式可避免双回同时跳闸事故的发生。 关键词：220kV输电线路，杆塔，雷击，防雷保护 Abstract Lightning disaster seriously affects peoples normal life, from the damage of facilities to the occurrence of large-scale blackout accidents, so the prevention of lightning disaster is still the key to the safe and stable operation of the power system. According to statistics, lightning accident will not only cause single-phase flashover of transmission line tower, but also cause serious tripping accident of two circuits at the same time. According to the special topography, complex line structure and other factors in Shiyan mountain area, lightning accidents occur frequently, and the stability of local power system is seriously threatened. In the past five years, lightning flashover accidents occurred many times on 220kV transmission lines in this area. Most of the accidents were caused by tower counterattack trip caused by lightning, which had a bad impact on the safe and stable operation of power system in Shiyan area. In this paper, the fault analysis and recurrence of two 220kV transmission lines in this area are carried out, and the lightning resistance performance of the area is evaluated. The differentiated lightning protection is adopted as the lightning protection criterion, and the lightning protection strategy is formulated, which has reference signifi