Disturbance identification method used during intrusion of lightning waves in transformer substation

Abstract

The invention relates to a novel disturbance identification method used during intrusion of lightning waves in a transformer substation, which comprises the following steps of: (1) monitoring a voltage signal of a busbar in real time; (2) performing S transformation on the voltage signal in failure, and establishing a module time-frequency matrix of the voltage signal; and (3) calculating the amplitude of fundamental waves, the times of primary harmonic waves, and the maximum amplitude of the primary harmonic waves by using the module time-frequency matrix, wherein the drop of the amplitude of the fundamental waves of the voltage of the busbar serves as the evidence for judging faulted and non-faulted lighting or other interferences, and the times of the primary harmonic waves and the corresponding amplitudes thereof serve as the evidence for judging whether lighting stroke occurs. Characteristics of a disturbance signal are extracted by using an S transformation technology suitable for analyzing an instable signal; and identification data are established according to the times of the primary harmonic waves of a transient voltage signal and the corresponding amplitudes thereof, aswell as the drop difference of the voltages of the fundamental waves under different disturbance conditions; and moreover, the method has the advantages of simplicity, convenience, high sensibility and accuracy for identification, and is easy for engineering realization.

Description

technical field [0001] The invention relates to a disturbance identification method for lightning wave intrusion into a substation. Background technique [0002] The actual operation data of the power grid shows that more than 40% of the fault trips of transmission lines are caused by lightning strikes, and the extreme cases can be close to 80%. In recent years, with the rapid development of social economy, line tripping caused by external damage has become the second largest factor after lightning strikes, and most of them are caused by crane construction. For line faults with unsuccessful coincidence, according to the current dispatching operation regulations, it is required to send a force immediately to restore the power supply as much as possible to ensure the reliability of power supply and the stability of the power grid. It is possible for faults caused by natural causes such as lightning strikes, pollution flashovers, and bird damage. However, for faults caused by...

AI Technical Summary

Problems solved by technology

Although the recognition accuracy of this method is high, the structure of the artificial neural network is complex, a large amount of training is required, the amount of calculation is large, and the practicability is not strong.

[0011] It can be seen that the existing research on lightning strike recognition does not have a completely practical and effective method

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