Considering wind speed variability in real-time voltage stability assessment using Thévenin equivalent methods

In this paper, wind speed models are used to consider its variability in real-time voltage stability assessment using Thévenin equivalent methods. A stochastic differential equation was used to produce a set of wind speeds required for the simulation scenarios together with a very short-term forecast based on a probabilistic method, which provides the means for including anticipation in the stability assessment.

This is achieved by representing the variation in the wind as an uncertainty in the Thévenin equivalent parameters, which are used for wide-area assessment, and studying corresponding changes in the stability boundary for a specific time horizon. The methodology was tested with time domain simulation a cigré benchmark system for network integrations of renewables, where the approach successfully represented the final Thévenin Equivalent parameters with a maximum error of 2.5% of the estimated variables, for a time horizon of 1 minute in the used forecast.