【摘要】 雷电流幅值累积概率分布是雷电活动规律的重要指标。通过对ADTD闪电定位系统监测的雷电资料的数理统计分析,采用IEEE工作组和《DL/T620-1997》推荐的公式对比分析了重庆地区的雷电流幅值累积概率的拟合效果。结果表明:雷电流幅值累积概率分布特征随极性存在显著差异,雷击大地密度随雷电流幅值不同而差异较大;同时,采用IEEE工作组推荐的公式拟合ADTD系统监测的雷电流幅值累积概率分布效果最佳,与IEEE推荐的雷电流幅值概率分布特征吻合;而采用《DL/T620-1997》中累积概率分布公式拟合,其结果与之采用概率分布特征差异较大;在此基础上获得了重庆地区的雷电流幅值累积概率分布公式,为防雷减灾活动提供了理论依据。更多还原

【Abstract】 The cumulative probability of lightning current amplitudes is one of the most significant parameters of lightning flash.Here presented are the statistical data of the first-stroke current of lightning flash, collected by LLS(Lightning Location System) of ADTD type.Negative first strokes have traditionally been considered to produce the worst stress on the earth.The positive strokes have about the same median current value as the negative first strokes and longer fronts,thus producing less stress.However,their duration is longer than that of the negative strokes.Therefore,we estimate the first-stroke current distribution in Chongqing using the empirical equations from the IEEE standards and the DL/T standards,respectively. It is found that the first-stroke current distribution is changed with the polarity and the density of lightning stroke is different with the intensity of lightning current.The LLS-inferred peak current distribution estimate equation according to the Task Force recommendations into IEEE standards is effective, because the results according to the Task Force recommendations into IEEE standards fit more suitably to the statistical data than those according to the power team recommendations into DL/T standards.更多还原