Online identification method of low-frequency oscillation mode of electric power system, online identification device of low-frequency oscillation mode of electric power system and electronic equipment

Abstract

An embodiment of the invention provides an online identification method of a low-frequency oscillation mode of an electric power system, an online identification device of the low-frequency oscillation mode of the electric power system and electronic equipment. The method comprises the following steps of based on operation measurement of the electric power system, sequentially using a stochastic subspace method and a clustering algorithm to obtain a first primary identification result; based on different combinations of operation measurement corresponding to the first primary identification result, obtaining a precise identification result of the low-frequency oscillation mode; based on each operation measurement of the electric power system, obtaining a second primary identification result; performing clustering analysis after the precise identification result is removed from the second primary identification result, and obtaining a missing mode; based on different combinations of theoperation measurement corresponding to the missing mode, obtaining a precise identification result of the missing mode; and using the whole of the two precise identification results as a final identification result of the low-frequency oscillation mode of the electric power system. The online identification method in the embodiment has the advantages that the low-frequency oscillation mode of theelectric power system can be more reliably, precisely and comprehensively identified, and the online monitoring of the low-frequency oscillation mode is realized.

Description

technical field [0001] The present invention relates to the technical field of power system analysis, and more specifically, relates to an online identification method, device and electronic equipment for a low-frequency oscillation mode of a power system. Background technique [0002] In the power system, when the generators run in parallel through the transmission line, if there is no damping in the system, under the action of the disturbance, the power flow between the generator rotors and the transmission line will continue to oscillate, because the oscillation frequency is very low , this phenomenon is called low-frequency oscillation. The low-frequency oscillation mode with weak damping or even negative damping will bring great harm to the safe and stable operation of the power system. Real-time identification of the low-frequency oscillation mode and its mode can be used to judge whether the system is stable, provide early warning information, and formulate vibration ...

AI Technical Summary

Problems solved by technology

However, the method based on mathematical model is vulnerable to the limitation of inaccurate modeling, which leads to low recognition accuracy, while the method based on large disturbance signal can only perform pattern recognition after a large disturbance occurs in the system but not when the system is running normally. Neither method is suitable for online real-time identification of oscillatory modes

The noise-like method uses the noise-like signal generated by the random disturbance in the system to identify the oscillation mode, but there are problems in this type of method that false modes may be identified, modes may be missed, and the identified modes may have large errors.

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