Predicting Post-contingency Stability Margin Using Synchrophasors

This paper proposes a region-wise dynamic stability assessment scheme to real-time predict stability margin of a power system after given contingencies. The proposed scheme is able to efficiently and strategically conduct simulations to dynamically determine a security region of the system's operating conditions. By means of phasor measurement units (PMUs), the location of the current operating point can be determined within or outside of the security region to predict the system's post-contingency stability margin. The margin information is valuable for system operators to obtain timely awareness of potential instability and take preventive control actions when necessary. The proposed scheme is demonstrated on Tenaga Nasional Berhad system by simulation studies to show its performance.