On the mechanism of transient instability of power systems

A. N. Michel, V. Vittal

Research output: Contribution to journalArticlepeer-review

1 Scopus citations


In recent studies, it has been verified heuristically and experimentally (via simulations) that instability in power systems due to a fault occurs when one machine or a group of machines, called the critical group, loses synchronism with the remaining machines. Using energy functions associated with a critical group (rather than system-wide functions), transient stability results which are less conservative than other existing results, have been obtained. The existence and identity of a critical group is ascertained in these studies by off-line simulations. In this paper, we present results, for power systems with uniform damping, which establish analytically the existence and the identity of the critical group of machines due to a given fault. We also present a result to determine estimates of the domain of attraction of asymptotically stable equilibrium points in power systems. The results presented herein can potentially be used on-line to determine which machines belong to a critical group, and to use this information for corrective action (e.g., shedding of the critical generators or fast valving for these generators). The applicability of the present results is demonstrated by means of a specific example (a 162-bus, 17-generator model of the power network of the State of Iowa).

Original languageEnglish (US)
Pages (from-to)413-434
Number of pages22
JournalCircuits, Systems, and Signal Processing
Issue number3
StatePublished - Sep 1985
Externally publishedYes

ASJC Scopus subject areas

  • Signal Processing
  • Applied Mathematics


Dive into the research topics of 'On the mechanism of transient instability of power systems'. Together they form a unique fingerprint.

Cite this