作　　者： ; ; ;

机构地区： 华南理工大学电力学院

出　　处： 《高电压技术》 2018年第3期772-778,共7页

摘　　要： 雷击是架空输电线路跳闸的主要原因,而基于标准雷电冲击下的绝缘子闪络判据应用于反击时有一定的局限性。为此在开展基于线路反击短尾波的仿真与试验研究中,基于PSCAD/EMTDC电磁暂态仿真软件建立了110 k V同塔双回鼓形塔的雷电反击模型,并仿真分析了雷击塔顶时杆塔呼高、接地电阻以及雷电流模型（双指数波、Heidler波等）对绝缘子两端短尾波波形电压的影响;基于现有冲击发生器设计了满足不同短尾波参数的短尾波冲击试验回路,并开展了试验研究。仿真结果表明,呼高较高时短尾波波头时间较短;接地电阻减小时短尾波峰值、波头和波尾时间都明显减小;而Heidler波与双指数波反击时产生的短尾波波形差异较大;绝缘子短尾波波头时间在0.2~2.0μs之间,波尾时间基本集中于5~10μs之间。试验结果显示,绝缘子的正负极性短尾波冲击U50%比标准雷电冲击U50%大约25%~30%,表明短尾波与标准波冲击下闪络判据差异较大故对反击耐雷水平的计算结果有着重要影响。后续将进一步开展闪络判据、海拔校正方法以及空气间隙雷击物理机理研究。 Lightning is the main reason for the trip of transmission line, however, the lightning flashover criterion based on standard lightning impulse has some limitations in back flashover criterion calculation, thus it is necessary to research the simulation and experiments on the short-tail voltage wave under transmission line back flashover. Based on the PSCAD/EMTDC simulation software, we established a back flashover model of the 110 k V double-circuit transmission line.Meanwhile, we simulated and analyzed the influences of the tower height, lightning current model（double exponential wave and heidler wave） and grounding resistance on the waveforms. Based on the present impulse voltage generator in the laboratory, the impulse voltage circuit that meets the requirement of different short-tail voltage waveform was designed, and the experiment was carried out. The results of simulation show that the wavefront of short-tail voltage wave is shorter if towers are higher. The peak, the wavefront, and the wavetail decrease obviously with the decrease of grounding resistance, and the short-tail voltage wave generated by double exponential current is different from that generated by heidler current. In addition, the wavefront is between 0.2~2.0 μs and the the wavetail mainly focuses on 5~10 μs. The experimenal results show that the insulator U50% under short-tail voltage wave is higher than that under standard lightning wave by 25%~30%, which shows that the backflashover criterion under these two kinds wave has a large difference, thus the waveform of impulse voltage greatly influences the backflashover withstand calculation result.

关 键 词： 防雷 同塔双回 反击 短尾波 冲击回路

领　　域： []