Electric transmission line icing state assessment method

Abstract

The invention relates to an electric transmission line icing state assessment method based on the BP neural network and a fuzzy expert system. The method comprises the following steps that (1), ambient temperature and ambient relative humidity are obtained, whether the temperature and the humidity reach an icing condition is judged, and if yes, the step (2) is executed; (2), ambient temperature different delta T, icing duration F and icing thickness H are obtained, and the icing weighted value of ambient temperature difference, the icing weighted value of equivalent icing thickness and the icing weighted value of icing duration are calculated out; (3), the BP neutral network is used for carrying out data fusion on the icing weighted values, the line icing probability is calculated out, if the line icing probability is 0, an output line is not iced, and if the line icing probability is 1, the step (4) is executed; (4), the ambient temperature different delta T, the icing duration F and the icing thickness H obtained in the step (2) are used as input of the fuzzy expert system, and assessment results are output through fuzzy reasoning. Compared with the prior art, the method has the advantages of being precise in assessment and the like.

Description

technical field [0001] The invention relates to a method for evaluating the icing state of a transmission line, in particular to a method for evaluating the icing state of a transmission line based on a BP neural network and a fuzzy expert system. Background technique [0002] As we all know, among the various natural disasters suffered by the power system, ice disaster is one of the most serious threats. Compared with other accidents, ice disasters caused more serious losses to the power grid, ranging from flashover tripping of power transmission and transformation equipment and damage to hardware, to severe cases of disconnection of overhead lines, collapse of towers, and even paralysis of large-scale regional power grids . During ice disasters, traffic is blocked, communication is interrupted due to bad weather, ice and snow cover mountains, and it is extremely difficult to repair power, which often causes long-term power outages on the power grid, causing serious losses...

AI Technical Summary

Problems solved by technology

But its correlation is poor, and the data sample size for analysis is too small

Due to the short research and development time, the icing status assessment, fault diagnosis and early warning research of overhead lines based on massive field data have not yet been carried out, and no scientific utilization method has been proposed for the collected field data, resulting in a large amount of useful field data not being fully utilized

The functions of the line icing monitoring system of various domestic power grid companies generally include: data collection and processing, equipment management, statistical analysis, parameter setting, trend analysis, alarm service and icing growth trend analysis, etc., where the alarm only uses the set alarm threshold The unique single-value alarm mode, the alarm accuracy is not high

[0004] Due to technical defects and inaccurate measurement techniques, the current on-line icing monitoring technology needs to be continuously improved to improve the accuracy of assessment. Studies have shown that icing on transmission lines is greatly affected by meteorological factors, especially ambient temperature and relative humidity. have a decisive influence on the formation of icing

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