以雷电机理诠释大底盘建筑群电源SPD配置

Interpretation of Power SPD Configuration for Large‑chassis Buildings by Lightning Mechanism

引入雷电冲击电流分时段特性的重要机理,在细究电感特性的基础上,以电感线路电流不能突变为原理,解释说明雷击建筑物时的高电位在雷击“换路”一刹那间先于雷电流发生,并在大底盘建筑群内可靠传导,形成一全范围的高电位“等电位面”。据此得出结论:大底盘建筑群是一栋电位紧密关联的防雷建筑物,在装设电源SPD时应将大底盘地面上多栋物理形态分开的建筑合并视为完整的单一一栋建筑,并根据低压电源线路进出大底盘建筑群的不同情况分别按GB 50057-2010《建筑物防雷设计规范》第4.3.8条第4、5款进行电源SPD配置。

The important mechanism of lightning impulse current characteristics in different periods is brought in the interpretation,and based on the detailed study of the inductance characteristics and the principle that the inductance line current cannot be suddenly changed,it is explained that the high potential when lightning strikes buildings precedes the lightning current at the moment of lightning strike“circuit‑changing”,and it is reliably conducted in the large‑chassis buildings,forming a full range of high potential“equipotential surface”.Therefore,it is concluded that the large‑chassis buildings is a lightning protection building with closely related potentials.When installing the power SPD,multiple buildings with separate physical forms on the ground of the large chassis should be combined and deemed as a complete single building,and the power SPD configuration should be carried out according to the different situations of low‑voltage power lines entering and leaving the large‑chassis buildings in accordance with Items 4 and 5 of Article 4.3.8 of the Design Code for Protection of Structures against Lightning(GB 50057-2010).