Calculation and Visualization of Power System Stability Margin Based on PMU Measurements

This paper introduces the concept of the Region Of Stability Existence (ROSE) and describes the framework for utilizing PMU data for computing of this region and operational margins. The approach presented in this paper is an automated process to continuously monitoring the transmission system in real-time environment by accurately calculating power system stability margins. Voltage constraints, thermal limits and steady-state stability are simultaneously monitored during the analysis. The region is shown on the planes of two phase angles and real powers. The paper also demonstrates the effect of remedial actions on the region. The approach is illustrated by using the ISO New England´s real-time model, SCADA data and PMU measurements. The study results show that this approach is effective in improving the reliability of the ISO New England´s transmission network and may be used for preventing major blackouts.