Prediction method for rapidly judging power system transient stability

Abstract

The invention relates to a prediction method for rapidly judging the power system transient stability. The technical characteristics of the prediction method comprise the following steps that the real-time measurement data of disturbed power angle trajectories are acquired by using a WAMS in each judgment period; a multicomputer system performs homological grouping on the measurement data; the power angle prediction trajectories in a period of time in the future are acquired by using an improved LS-SVR algorithm; the maximum value of the power angle is judged so as to perform stability judgment; the power angle prediction trajectories are split into two subsequences by using phase-space reconstruction and the standard deviation sigma and the standard deviation offset eta of each subsequence are calculated; and whether the standard deviation offset eta is less than 0 is judged so as to perform system stability judgment. Transient stability prediction is performed by using the phase-space reconstruction criterion so that the prediction time and the accuracy can be obviously enhanced in comparison with the conventional criterion, stability loss prediction time is improved to 1.1s from 1.4s, and thus the precious time is won for subsequent emergency control and the safety stability of the system can be enhanced.

Description

technical field [0001] The invention belongs to the technical field of power system transient stability prediction, in particular to a prediction method for quickly judging the power system transient stability. Background technique [0002] With the continuous development of large-scale interconnected power grids, the safe and stable operation of power grids is facing new challenges, so there are higher requirements for power system transient stability analysis methods. Traditional power system transient stability prediction methods mainly use the phase trajectory geometric characteristic criterion and the power angle difference threshold value criterion. Using the above criterion to predict has problems such as long prediction time and poor accuracy. Contents of the invention [0003] The purpose of the present invention is to overcome the deficiencies of the prior art, and provide a reasonably designed and highly accurate prediction method for quickly judging the transie...

AI Technical Summary

Problems solved by technology

The traditional power system transient stability prediction method mainly uses the phase trajectory geometric characteristic criterion and the power angle difference threshold value criterion. Using the above criterion to predict has problems such as long prediction time and poor accuracy.

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