Transient stability evaluation method based on kinetic energy of post-fault trajectories

It is very important to maintain supply reliability under the deregulated environment. The transient stability problem is one of the major concerns in studies of planning and operation of power systems. Nowadays, the time domain simulation is the best available tool for allowing the use of detailed models and for providing reliable results. The main limitations of this approach involve large time of computations. Therefore, this paper proposes a transient stability evaluation method using minimum transient kinetic energy of post-fault trajectories. This method can estimate critical clearing times with only two points of the minimum transient kinetic energy even if the trajectories after a clearing time are stable or unstable. The validity of the proposed method is shown by simulation studies with the IEEJ EAST 10 machine 47 bus system.