Development of Two-Time-Scale CUEP/BCU method applied for stability analysis of power systems

Abstract

In transient stability analysis context, direct methods (energetic methods) appear as a fast solution for on-line stability analysis, and among them the CUEP (Controlling Unstable Equilibrium Point) method associated with the BCU (Boundary Controlling Unstable Equilibrium Point) numerical algorithm rises as the most effective direct method in transient stability assessment. However, traditional CUEP/BCU method does not take advantage of the several time scales in the dynamic of these systems, what leads to: (i) excessively conservative stability analysis and (ii) numerical difficulties in CUEP calculations. The Two-Time-Scale (TTS) CUEP/BCU method takes advantage of the existence of fast and slow time scales in the power system mathematical model to overcome the aforementioned shortcomings, but with extra gains: (i) small order formulation of the fast and slow subsystems and (ii) possibility of assessing different stability problems (transient and voltage stability) associated with different time scales (short and mid-term stability). The present research project proposes development for the TTS CUEP/BCU method in the following directions: (i) to extend the TTS CUEP/BCU theory for more general power system models (singular perturbed models with multiple time scales and differential-algebraic models), (ii) to extend the TTS CUEP/BCU method for transient and voltage mid-term stability analysis, and (iii) to apply the TTS CUEP/BCU method for complex power systems' models. (AU)