特高压交流同塔双回输电线路邻近建筑物时畸变电场研究

Distorted Electric Field of the Building Near UHVAC Double Circuit Transmission Lines on the Same Tower

为了解特高压交流输电线路邻近建筑物时畸变电场,采用有限元法计算了1 000kV交流同塔双回输电线路邻近不同结构和材料建筑物时的工频电场。首先建立了含弧垂导线、钢架和空气场域的计算模型和有限元模型;然后计算分析了钢架附近地面、阳台和屋顶的工频电场,通过与实验模型比较验证了计算方法的有效性;最后分析了钢筋和砖土材料房屋楼顶的畸变电场,比较了2种房屋是否开窗时阳台和室内的场强。结果表明,有限元法可有效计算建筑物周围的工频电场;靠近导线侧房屋棱角及棱边附近工频电场畸变较大,钢筋和砖土房屋楼顶棱边中心处畸变电场分别为10.40kV/m和6.02kV/m,较不存在房屋时分别畸变了123.18%和29.18%;砖土材料对室内电场屏蔽效果较差,其一层室内最大场强可达4.82kV/m;开窗会使钢筋房屋阳台处电场从32.2mV/m增大到1.95kV/m,但砖土房屋阳台电场变化较小。

To research distorted electric field of the building near UHV AC transmission lines, a finite element method/FEM} was applied to calculate the distorted electric field produced by 1 000 kV AC double circuit transmission lines on the same tower, including the electric field of reinforced building and brick building. Firstly, the calculation model and finite element model of transmission lines with sag, steel frame and air field were established. Then, the electric field of the balcony, the roof and the surrounding area of the steel frame were calculated. UHV AC experiments verified the effectiveness of the calculation method. Finally, the distorted electric field of the reinforced building roof and the brick building roof are researched. In the cases of window opened and closed the electric field of both the balconies and indoors are compared. The results show that FEM can effectively calculate the distorted electric field of the buildings. The electric field of the building edges and building corners are seriously distorted. The electric field of the reinforced building roof and the brick building roof were 10.40 kV/m and 6.02 kV/m, respectively, distorted by 123. 61% and 29. 18%, respectively. The reinforced building had a stronger shielding effect on indoor electric field than the brick building, and the indoor electric field of the brick building reached 4.82 kV/m; the electric field change of the reinforced building was greater than that of the brick building by opening the window, while the electric field of reinforced building balcony reached 1.95 kV/m from 32.22 mV/m.