Spectral clustering-based voltage source converter based high voltage direct current transmission (VSC-HVDC) AC-DC system optimal splitting section search method

Abstract

The present invention relates to a spectral clustering-based voltage source converter based high voltage direct current transmission (VSC-HVDC) AC-DC system optimal splitting section search method. The method is characterized by comprising the steps of constructing an undirected edge weight graph G of a power system according to a power system structure; calculating an adjacent weight matrix W and a degree matrix A according to trend data; determining whether the system is unstable due to large disturbance; dividing a generating unit into k homolog groups according to a rotor power angle rocking curve after a generator is disturbed, and updating the adjacent weight matrix W and the degree matrix A; updating the adjacent weight matrix W and the degree matrix A according to a VSC-HVDC converter station placement; calculating a standardized Laplacian matrix LN; and clustering, according to the homolog group number k, feature vectors corresponding to the first k smallest feature values of the standardized Laplacian matrix LN, so as to determine the optimal splitting section, wherein the feature vectors are calculated by using a k mean value clustering algorithm. The method is scientific and reasonable, has high applicability and high reliability.

Description

Technical field [0001] The invention belongs to the technical field of power system transient safety and stability and control, and in particular relates to a method for searching the optimal splitting section of an AC / DC system containing VSC-HVDC based on spectral clustering. Background technique [0002] It can be known from the large blackout accidents that have occurred at home and abroad in recent years that although a series of measures have been taken to improve the stability of the system in the operation and design of the power system, it is still possible to encounter sudden failures to make the system lose stability. It is necessary to understand the phenomenon after the system loses stability and take corresponding measures to reduce the damage caused by the damage of stability, and quickly restore the system to stable operation. De-sequencing is an effective means to limit the collapse of the power system after a large disturbance. The large-scale blackout can be av...

AI Technical Summary

Problems solved by technology

Although heuristic search methods usually have the advantages of high flexibility and fast calculation speed, because these methods tend to converge locally rather than global minimum, there is no guarantee whether the final solution is the optimal solution

Transforming the NP problem of solving the optimal section into other relatively easy-to-solve problems is a current hot research direction. The spectral clustering algorithm can transform the actual NP problem into a minimum-cut problem in graph theory. Through the relaxation method, it can be obtained in The optimal solution in the real number threshold has high computational efficiency and will not lose the solution set, but if the traditional spectral clustering algorithm only considers solving the minimum cut and ignores the density distribution inside the subgraph after cutting, a certain subgraph usually appears The phenomenon that the interior only contains isolated nodes is not suitable for application in power systems to solve practical problems, but existing studies have shown that if the minimum norm cut criterion is used, the phenomenon of nodes being separated into groups can be avoided

Images