Combinatorial weighting method for lightning transformation effect evaluation of 500kV transmission lines

As the effective lightning protection measures can improve the lightning protection performance of transmission line and reduce line shielding failure rate, an assessment method based on combinatorial weighting method is proposed to formulate lightning protection measures in accordance with the e valuation process of screen-selection-optimization. Economic and technical analysis of several commonly used lightning transformations is performed first to verify their effectiveness. Then the combinatorial weighting method is applied to calculate the weight value of these measures relative to the target according to the relationship between objectives and guidelines, furthermore the theoretical optimal lightning protection measure is selected. The application of this method is illustrate d with a typical 500 kV transmission line under complex terrain, and the expected evaluation result shows the lightning protection performance can meet the transformation requirements. Thus this method can be suitably used as reference in practical engineering.