On Power System Controlled Separation

Abstract

This paper describes verification of five conjectures related to power system controlled separation. It attempts to verify that the location of uncontrolled separation (loss of synchronism or out-of-step operation) is independent of the location and severity (short-circuit duty or duration) of the initial faults, that the location depends on the prevailing network configuration and load level, and that it takes place one operation at a time (cascades). Verification of these conjectures would allow controlled separation during a disturbance in real-time, using the present communication and protection systems, and results in a minimal load and generation imbalance. Two actual power systems were used, a 50-bus system to establish the procedure for controlled separation and a 640-bus interconnection to apply the procedure. Data representing static and dynamic behavior of the two power systems were obtained from the operating utilities, and the many required simulations were conducted using EPRI Power System Analysis Package (including IPFLOW and ETMSP programs).

System splitting strategy considering power system restoration

“…Multiple case studies are developed to demonstrate the effectiveness of the algorithm to different system conditions. It is important to note that there are a few seconds for controlled islanding after the system suffers a severe fault [16]. Based on the simulation results, it can be seen that the proposed extended ICI algorithm can meet the requirement of real-time controlled islanding while planning a parallel power system restoration in case of any eventuality.…”

Constrained spectral clustering‐based methodology for intentional controlled islanding of large‐scale power systems

“…In our methodology, the value of r is the number of islands to be created. This value corresponds to the number of identified coherent groups of generators [4][5][6][7][8][9][10][11][12][13], as current practices (e.g., [23,24]) suggest that the number of islands should be equal to the number of coherent groups obtained after the severe disturbance. Note that, nevertheless, the proposed methodology can determine an islanding solution for any given number of islands.…”

“…ICI is an adaptive control strategy for systems under emergency and in extremis states [1][2][3][4][5]. After a severe contingency, ICI intentionally separates the bulk network into several self-sustaining electrically isolated islands.…”

“…Since including all of these in the ICI problem may result in a very complex problem that could not be solvable in a limited timeframe, only a subset of constraints can be considered [13]. The exclusion of some constraints and the inherent characteristics of the system mean that additional corrective measures [1][2][3][4][5] are necessary to ensure that each island retains its stability and security margins in the post-islanding stage [5][6][7][8][9][10][11][12][13].…”

“…4 The paper is organised as follows. Section 2 presents the background material on spectral graph clustering, and introduces the ICI problem considered in this paper.…”