In this paper, a new method is proposed for directly evaluating approximate lightning channel-base-current (CBC) parameters ($I_{m}$, (di/dt)_max, t_FD, and t_SD) and analytical function parameters (AFPs) of the CBC based on the measured lightning magnetic fields using a deconvolution and differential evolution (DE) method. This proposed method comprises two sequential steps. The first step is for determining the lightning CBC based on the measured magnetic field using modified transmission line model with exponential current decaying with height (MTLE) through deconvolution, while the second step is for evaluating the AFPs (Heidler's function) corresponding to the lightning CBC obtained from the first step. Data from the measured magnetic field above ground level (z = 10 m) at different horizontal distances (r = 9 km, 4.6 km, 2 km, and 50 m) from the lightning channel are considered for testing the proposed method. The sum of two Heidler's functions is used to represent the lightning CBC; and its parameters, namely I₀₁, I₀₂, τ₁₁, τ₁₂, τ₂₁, τ₂₂, n₁, and n₂ are identified using DE as a tool. Further, this methodology is helpful in the evaluation of the CBC parameters and mathematical modeling of the lightning CBC and the estimation of the lightning current through the channel using data from the measured magnetic field for different engineering return stroke models.

中文翻译：

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基于实测雷电磁场的近似通道基电流及其解析函数参数的评估

在本文中，提出了一种直接评估近似闪电通道基电流（CBC）参数的新方法（$I_{m}$, (迪/dt)_最大,吨_FD , 和吨_SD ) 和 CBC 的分析函数参数 (AFP) 基于使用解卷积和差分演化 (DE) 方法测量的闪电磁场。这种建议的方法包括两个连续的步骤。第一步是根据测量的磁场使用修正传输线模型确定闪电 CBC，其中指数电流随高度衰减（MTLE）通过反卷积，而第二步是评估与闪电 CBC 对应的 AFP（海德勒函数）从第一步得到。来自地面以上测量磁场的数据（z = 10 m) 在不同的水平距离 (r = 9 km、4.6 km、2 km 和 50 m）距离闪电通道被考虑用于测试所提出的方法。两个海德勒函数之和用于表示闪电CBC；及其参数，即一世₀₁ ,一世₀₂ ,τ₁₁、τ₁₂、τ₂₁ ,τ₂₂ ,n₁, 和 n₂使用 DE 作为工具进行识别。此外，该方法有助于评估 CBC 参数和闪电 CBC 的数学建模，以及使用来自不同工程回击模型的测量磁场数据估计通过通道的雷电流。