模拟雷电流多分量组合脉冲与通道光强度关系

Relationship between simulated multi-component waveforms of the lightning current pulse and channel light intensity

搭建了集中参数链式网络电路,输出3组模拟雷电流多分量组合脉冲波形,含3个模拟回击脉冲和15个模拟M分量脉冲及跟随的连续电流。采用红光敏感型(探测波长范围200~1000 nm,峰值响应600 nm)和近红外敏感型(探测波长范围400~1000 nm,峰值响应800 nm)两种光电探测器,对放电间隙辐射光强进行探测,同步测量了通道电流。分析了电弧通道内电流与光强脉冲波形特征参数之间的相关性,结果发现,光强峰值与电流峰值以及光强10%~90%上升时间和电流10%~90%上升时间之间均存在线性关系。雷电流多分量组合脉冲转移电荷量与光强-时间积分也线性相关,为通过光学观测反演雷电流转移电荷量提供了依据。总体上,相对于红光敏感型光电探测器,近红外敏感型光电探测器输出的光强波形能更好地吻合模拟雷电流多分量组合脉冲波形变化趋势,从而有望更准确地对放电转移电荷量进行反演。

Three categories of multi-component waveforms of lightning current,composed of three simulated return-stroke pulses and fifteen simulated M-component pulses along with the underlying background current,are generated by the ladder network formed by series connected inductor-and-capacitor elements.Two types of photodetectors,namely,a red-light sensitive one with a detection wavelength range of 200-1000 nm peaking at 600 nm,and a near-infrared sensitive one with a detection wavelength range of 400-1000 nm peaking at 800 nm,were used to record the luminosity of the discharge gap channel.Parameter correlations were analyzed between the simulated lightning multi-component current and the corresponding channel luminosity.Results show that the peak luminosity is linearly correlated with the peak current,and that there is also a linear relationship between the luminosity 10%-90%rise time and current 10%-90%rise time.Correspondingly,the resulting luminosity-time integral is linearly related to the current charge transfer.An important implication of this result is that the channel optical observation may well be suitable for the inversion of lightning current transfer charge.In general,however,compared to that from the red-sensitive photodetector,the luminosity waveform from the near-infrared sensitive photodetector is observed to better match the evolution trend of current,which implies that it might allow for a more accurate estimation of the current transfer charge.