Impact of wind generation uncertainty on power system small disturbance voltage stability: A PCM-based approach

The connection of wind generators with electric power system influences the system stability and nodal voltages. This paper performs uncertainty analysis to investigate the impact of wind generation variation on the small disturbance voltage stability. The probabilistic collocation method (PCM) is presented as a computationally efficient method to conduct the uncertainty analysis. It has been implemented in a simple system to demonstrate its applicability in analyzing wind generation uncertainty. More case studies on a larger system are conducted to obtain a deeper understanding of how the system voltage stability is affected by the integration of DFIG-based wind farms. As compared with the traditional Monte Carlo simulation method, the collocation method could provide a quite accurate approximation for the eigenvalue probabilistic distribution with fewer simulation runs.

► Voltage instability is possible when eigenvalue passes the origin.
► Small disturbance introduced by wind uncertainty influences eigenvalue distribution.
► Third order PCM model provides accurate approximation of the eigenvalue loci.
► PCM requires a much smaller number of model runs compared with Monte Carlo method.
► Voltage security information is obtained through calculation of the proposed PSDVS.