| CPC G01R 31/085 (2013.01) [G01R 31/003 (2013.01)] | 4 Claims |

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1. A method for providing an additional lightning protection measure of a whole transmission line, comprising:
performing a quantitative analysis on a tripping risk of a whole line due to a lightning shielding failure according to a multi-dimensional analysis method for a tripping risk of a whole transmission line due to a lightning shielding failure;
identifying a weak link of the whole line based on a lightning shielding failure risk value; and
providing the additional lightning protection measure for the weak link;
wherein the multi-dimensional analysis method for a tripping risk of a whole transmission line due to a lightning shielding failure comprises the following steps:
step 1: extracting a size parameter of a main tower head, an insulation configuration for a line, a quantity of monitored thunderstorm days, and an average altitude for the line, and calculating a ground wire protection angle, a striking distance, and a corrected insulator flashover voltage by a processor;
step 2: setting an analysis group based on the protection angle, a terrain, a nominal height, and the quantity of thunderstorm days, and calculating the lightning shielding failure risk value of the line in each case based on a shielding principle of the transmission line by the processor;
step 3: analyzing, based on a calculation result in step 2, main factors affecting a lightning shielding failure risk of the line, and selecting a typical combination of a tower protection angle, the terrain, the nominal height, and the quantity of thunderstorm days based on an existing terrain proportion or a ground wire protection angle setting collected for the transmission line by the processor; and
step 4: extracting a weight of the selected typical combination of the tower protection angle, the terrain, the nominal height, and the quantity of thunderstorm days in step 3 based on a terrain proportion and tower usage of a whole line in a same area, and performing a quantitative analysis on a tripping risk of the whole line due to a lightning shielding failure by the processor;
wherein in step 4, the tripping risk of the whole line due to the lightning shielding failure is analyzed through weighted averaging of the typical combination:
![]() wherein hj represents a height of a jth type of tower; βj represents a proportion of a tower whose nominal height is hj; SFFφi,hjθ represents a lightning shielding failure risk when the tower protection angle is θ, the nominal height is hj, and an inclination angle of the ground is φi; αi represents a proportion of a section corresponding to a terrain whose inclination angle of the ground is φi to the whole line; and SFFeq represents the lightning shielding failure risk of the whole line; and
wherein the lightning shielding failure risk value of the line in each case of the typical combination is sorted by the processor to obtain a high-risk typical combination, in the line, a link whose nominal height, terrain, quantity of thunderstorm days, and protection angle are closer to the high-risk typical combination is the weak link.
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