基于解析数值法的配电房母排磁场屏蔽

鉴于室内配电房广泛使用的平板形大电流母排,根据母排实际尺寸、位置参数等构建了其工频磁场分布的计算模型,将解析法与数值分析相结合求得空间各点的磁感应强度,以便于磁场屏蔽效能的研究.考虑了配电房母排普遍采用的两种排列方式,着重讨论第一种排列方式对应三种屏蔽方案的屏蔽效果,经计算得出第三种方案的屏蔽效果较为理想.接着研究第三种方案对应屏蔽材料、屏蔽板和母排间距离、屏蔽板厚度和高度等对屏蔽效能的影响.结果显示通过增大材料的磁导率、增加屏蔽板厚度和高度、减小屏蔽板与母排间距离,屏蔽效能呈明显增大趋势.最后针对上述特征给出了提高屏蔽效能的可行建议,以降低配电房周围的磁污染,从而减小对电子设备的干扰和人体健康的影响.

Magnetic Field Shielding for Indoor Distributing Substation Busbars Based on Analytical-Numerical Method

Considering plane busbars with large current being generally used in indoor distributing substation, the paper presents the calculational model for the power frequency magnetic field (PFMF) based on dimension and structure factors and so on. Analytical approach and numerical approach are combined to calculate the magnetic inductive intensity in the space nearby the busbars so as to research shield efficiency. Considering two ranking modes adopted busbars, the paper emphasizes on discuss on shielding efficiency of the first sequence mode corresponding to three types of shielding programs. It is found by calculation that the third shield result is more ideal. In following, effectiveness of shielding materials, distance between shielding board and busbars, shielding board thickness and height to shield efficiency is researched to the third shield project. The results show that shielding efficiency is significantly increasing trend by increasing permeability material, increasing shielding plate thickness and height, reducing distances between shielding plate and busbars. Finally, feasible advises are put forward to improve shielding efficiency to reduce magnetic pollution surrounding the distribution.