Abstract:Reasonable designed ice-thickness on wires can protect the power grid against icing disaster and greatly reduce the overall construction cost of power grid projects. Therefore, the proper calculation of the diameter correction coefficients of ice thickness has important engineering application value.. The standard ice-thicknesses on different wire diameters are obtained through calculating with the diameter correction coefficients. However, the formulas for calculating diameter correction coefficients long in use are come from statistical fitting, that is restrictive in practical application. Based on the theoretical model of conductor icing and applied a simplified formula to calculate the droplets collision rate which is verified by comparison with the Finstad’s formula that has been universally accepted, a theoretical method for calculating the diameter correction coefficient is derived and applied to calculate and analyze the diameter correction coefficients under different icing types and meteorological conditions. The results show: the correction coefficient decreases with enlarging of the diameters in rime icing, contrarily it increases with enlarging of the diameters in glaze icing, and its value is between the preceding two''s under similar meteorological condition to rime&glaze mixed icing. Compared to the formula recommended by the new Chinese Power Industry Standard(DL/T5158-2012) and previous studies, the new theoretical method has preferable theoretical basis and universality, and is of practical value for anti-icing design of power transmission lines.