基于闪电定位系统（LLS）的闪电密度.一般原则

[中文适用范围]： This document introduces and discusses all necessary measures to make reliable and homogeneous the values of ground flash density, NG and ground strike point density, NSG, obtained from lightning location systems (LLSSs) in various countries. Only parameters that are relevant to risk assessment are considered. Le présent document décrit et étudie l'ensemble des mesures nécessaires pour produire des valeurs fiables et homogènes de NG à partir des différents LLS nationaux. Seuls les paramètres essentiels à l'évaluation du risque sont pris en compte. [外文原描述]： IEC 62858:2019 introduces and discusses all necessary measures to make reliable and homogeneous the values of ground flash density, NG and ground strike point density, NSG, obtained from lightning location systems (LLSs) in various countries. Only parameters that are relevant to risk assessment are considered. This second edition cancels and replaces the first edition published in 2015. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: - Two informative annexes are introduced dealing with the determination of lightning density for risk calculation (Annex A) and ground strike point calculation methods (Annex B).