750kV输电线路悬式绝缘子的均压特性

Voltage Sharing Characteristics of Suspension Insulator for 750 kV Transmission Lines Maintenance

沿绝缘子串电位分布不均匀,改善输电线路绝缘子串电位分布对绝缘子的设计及运行、维护特别重要。为更好地控制绝缘子串电位、电场分布,基于有限元方法考虑铁塔、分裂导线、避雷线等因素的影响,建立了750kV输电线路绝缘子串三维电场计算模型,从而计算得到了沿绝缘子串的电位分布曲线。通过分析讨论不同均压环上抗位置、环径、管径对绝缘子串电位、电场分布的影响,进而确定合理的均压环结构参数。结果表明,仿真计算时分裂导线、铁塔的影响不可忽略;均压环结构参数优化后,单片绝缘子最大承受电压及均压环表面最大电场均得到了改善,沿绝缘子串电位分布更为均匀。

Due to the inhomogeneous potential distribution along the insulator strings,to improve the potential distribution of insulator strings are particularly important for the design,operation and maintenance of insulators.In order to better improve the potential distribution and electric field distribution along the insulator strings,according to the actual situation of the insulators,insulator three-dimensional electric field calculation models for the insulator strings of 750 kV transmission lines,considering the effects of tower,bundle conductors,shielding line and so on,were set up based on the finite element method（FEM）,and the curve of potential distribution along the insulator strings was obtained.The impact of some factors,such as the location of grading rings,the diameter of grading ring and the caliber of grading ring,on the potential distribution of insulator strings were analyzed,and then the optimal structure parameters of grading ring were determined.The results show that,when simulating the potential distribution of insulator strings,the effects of the bundled conductor and tower cannot be ignored.When calculating the potential distribution of insulator strings based on the optimization of structural parameters of grading ring,the maximum withstand voltage of single insulator and the maximum electric field of the surface of grading ring are significantly improved,the potential distribution along the insulator string is more uniform.