Graph Partitioning Algorithms for Control of AC Transmission Networks: Generator Slow Coherency, Intentional Controlled Islanding, and Secondary Voltage Control

The vast size of a modern interconnected power grid precludes controlling and operating it as a single object. Subdividing a power grid into a number of internally coherent areas allows to cope with its inherent complexity and to enable more efficient control structures. This thesis focuses on discovering the power system structure to facilitate...

Slow Coherency Identification and Power System Dynamic Model Reduction by using Orthogonal Structure of Electromechanical Eigenvectors

Identifying generator coherency with respect to slow oscillatory modes has numerous power system use cases including dynamic model reduction, dynamic security analysis, or system integrity protection schemes (e.g., power system islanding). Despite their popularity in both research and industry, classic eigenvector-based slow coherency techniques...

Discovering Clusters in Power Networks from Orthogonal Structure of Spectral Embedding

This paper presents an integrated approach to partition similarity graphs, the task that arises in various contexts in power system studies. The approach is based on orthogonal transformation of row-normalized eigenvectors obtained from spectral clustering to closely fit the axes of the canonical coordinate system. We select the number of...

Controlled islanding of power networks based on graph reduction and spectral clustering

Intentional controlled islanding aims to split the power system into self-sustainable islands after a severe disturbance, but prior the uncontrolled network separation. Given its nature (i.e. last resort for blackout prevention), this emergency control technique must be adopted as quickly as possible. This paper proposes a computationally...