Power System Transient Stability Assessment Using Couple Machines Method

TL;DR

This paper introduces a hybrid direct-time-domain method for power system transient stability assessment that simplifies analysis by focusing on couple machines with high rotor speed differences, avoiding the need for COI calculation.

Contribution

It proposes a novel approach using couple machines and power-angle curve prediction for efficient transient stability analysis without COI.

Findings

Effective in transient stability assessment

Avoids the need for Center of Inertia calculation

Accurately predicts stability margin

Abstract

Analyzing the stability of the power system by using a few machines is promising for transient stability assessment. A hybrid direct-time-domain method that is fully based on the thinking of partial energy function is proposed in this paper. During post-fault period, a pair of machines with high rotor speed difference is defined as couple machines, and the stability analysis of the system is transformed into that of several pairs of couple machines. Based on the prediction of power-angle curve of couple machines within a sampling window after fault clearing, the proposed method avoids the definition of Center of Inertia (COI) and it can also evaluate the stability margin of the system by using the predicted power-angle curve. Simulation results demonstrate its effectiveness in transient stability assessment.