Use of Critical Clearing Time for Transient Stability Preventive Control

Abstract

Deregulation of electric power industries has begun in many countries and power system operations have become more difficult. Therefore, power system operators should consider not only economic load dispatch but also on-line stability aspects. In this paper, we pay attention to one of the most important transient stability indices, Critical Clearing Time (CCT), and propose a new transient stability preventive control method using linear relationships between CCTs and generator rotor angles. A preventive control to achieve a more stable operating point is carried out by generator output rescheduling, which are determined using the relationships between CCTs and generator rotor angles.