Abstract
Traditional voltage stability assessment methods do not include temporal
variation of renewable power generations like wind. This paper proposes
a novel methodology for probabilistic voltage stability assessment
methodology which can be used in conjunction with any of the existing
traditional voltage stability indices. Historical wind power data are
used to determine probabilistic distribution of wind power at future
instant based on wind power value at current instant. Based on the
probabilistic risk of increase and decrease of wind power at future
instant, two probabilistic voltage stability indices are computed. The
worse case value among the two indices are used as prediction of voltage
stability index at future instant, based on current system parameters.
Effectiveness of the proposed methodology in predicting proximity of the
system voltage collapse is illustrated through case studies and
time-series simulations. Results show that proposed methodology predicts
more realistic proximity to voltage collapse than traditional stability
assessments.