Transient Stability Assessment Using Individual Machine Equal Area Criterion Part II: Stability Margin

In the second part of this two-paper series, the stability margin of a critical machine and that of the system are first proposed, and then the concept of the nonglobal stability margin is illustrated. Based on the crucial statuses of the leading unstable critical machine and the most severely disturbed critical machine, the critical stability of the system from the perspective of an individual machine is analyzed. At the end of this paper, comparisons between the proposed method and classic global direct methods are demonstrated.