Reducing model complexity of DFIG-based wind turbines to improve the efficiency of power system stability analysis

Abstract

The growing number of doubly-fed induction generator (DFIG) based wind farms has significantly increased the model complexity and simulation burden for power system stability analysis. In this paper, a novel method to assess the modeling adequacy of DFIGs for small-signal stability analysis is introduced. By evaluating the damping torque contribution to stability margin from different DFIG dynamic model components, the proposed method provides a quantitative index to show the participation level of each DFIG model component in affecting power system damping performance. In addition, five DFIG model reduction schemes are established, and a novel strategy to reduce individual DFIG model complexity based on the participation level is proposed. The effectiveness of the proposed strategy has been demonstrated in the New England test system. It can be concluded that the proposed DFIG model reduction for dynamic studies is undoubtedly beneficial to system planner and operator, in the way of improving computational efficiency when analyzing large-scale power systems with the increasing penetration of wind energy.