Extended equal-area criterion: an analytical ultra-fast method for transient stability assessment and preventive control of power systems

Abstract

A unified approach to transient stability assessment of multimachine power systems is presented. It originates from the equal-area criterion applied to a two-machine equivalent of the system, combined with an analytical procedure totally free from any step-by-step numerical integration. The extended equal-area criterion thus devised provides analytical tools for transient stability analysis and sensitivity assessment. In turn, the latter furnishes transient stability limits and paves the way to control. Means to embed these transient stability techniques in a unified security assessment context are developed. Applications to system planning, operation planning and real-time operation are investigated and many practical uses are suggested. The method is scrutinized by a systematic exploration of 10 different power systems and many contingency scenarios, resulting in over 2500 simulations.