雷电灾害风险评估中A_m因子的选取方法研究

Research on the Selection Method of Factor A_m in the Evaluation of Lightning Disaster Risk

雷电击中建筑物附近的有效截收面积A m是雷电灾害风险评估的基础因子之一,目前广泛应用标准IEC 62305—2规定的选取方法。计算中未考虑项目所在位置的雷电环境及项目特性,计算结果缺乏针对性。从雷击建筑物附近可能产生的风险出发,分析附近雷击点的危害方式及危害程度,探讨根据工程实际确定参数A m值的一般方法。得出结论:参数A m值应在分析确定可能造成危险的雷击点的最远距离的基础上定量计算,以保证计算结果的针对性、科学性。建筑物附近的雷击点以雷电电磁脉冲的形式对内部电气电子设备造成危害,危害程度与该点雷电流强度、建筑物规模及防护措施等因素有关。

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