Short-term N-2 risk evaluation method for electric transmission line in thunder and lightning weather

Abstract

The invention discloses a short-term N-2 risk evaluation method for an electric transmission line in thunder and lightning weather. The method comprises the following steps: 1) carrying out statistics on time of various thunder and lightning levels issued by the meteorological department in a statistical period in a region; and at the same time, obtaining thunder and lightning information in corresponding thunder and lightning pre-warming levels through a thunder and lightning positioning system; 2) correcting the historical thunder and lightning pre-warming levels by actual thunder and lightning thunderbolt density to obtain accurate thunder and lightning process numbers of the thunder and lightning levels; 3) calculating the line thunderstrike trip failure rate of the region in the thunder and lightning level D in the statistical period; and 4) carrying out short-term N-2 risk evaluation to an electric transmission line set with failure risk. The method disclosed by the invention can provide ground for decision analysis of operators for power grid dispatching to immediately take risk pre-control measures of transferring the line load in advance so as to ensure that the level of loss of load of the system is minimum or maintained in an acceptable state under the predicted meteorological effect, so that the power distribution reliability is improved, the economic loss of the power grid is reduced and the reliable operation capacity of the power grid is improved.

Description

technical field [0001] The invention relates to risk assessment of transmission lines in lightning weather, specifically a short-term N-2 risk assessment method for transmission lines in lightning weather based on historical lightning statistics and correction, and belongs to the field of power system risk and reliability assessment. Background technique [0002] Lightning is extremely harmful to the power supply system. First, it will cause overvoltage, phase-to-phase short-circuit faults, flashover discharges to burn insulators, trip circuit breakers, breakdown and burn electrical equipment; secondly, strong lightning currents will generate huge electricity Dynamic and thermal effects, which can damage or burn electrical equipment and cause fires. [0003] At present, when lightning occurs, the line failure rate used in power system reliability calculation is the total failure rate of all lines that cause line faults instead of considering the line failure rate in lightnin...

AI Technical Summary

Problems solved by technology

[0006] The duration of faults in modern power systems is greatly shortened, and it is difficult for a single fault to pose a major threat to the stability of the power grid.

The traditional N-1 criterion gradually began to fail to meet the requirements of safe and efficient operation of the modern power grid. It is of great significance to study the N-m fault risk of the power grid

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