Study of sub-synchronous interactions in DFIG-based wind farms using the selective modal analysis technique

摘要

In this paper, the selective modal analysis method (SMA) is used for studying subsynchronous control interactions (SSCI) between wind farms based on DFIG wind turbines and capacitive series compensated transmission lines. The SMA method uses a reduced number of state variables for reproducing the modes of interest, and its effectiveness depends heavily on an appropriate selection of these variables. It is shown that this task is not straightforward when is used for studying the SSCI phenomenon. A guide for selecting the correct set of variables is presented. In addition, a procedure based on a state transformation is used for reducing significatively the number of variables required to reproduce the modes associated to the SSCI.