A Nonlinear Control Design to Improve the Dynamic Stability of a Multi-Machine Power System with DFIG-Based Wind Turbines

This paper proposes a nonlinear control approach for a multi-machine power system with DFIG-based wind turbines. The proposed approach aims at coordinating the design of the controllers of the doubly fed induction generator and that of the Static Synchronous Compensator (STATCOM) device. Its main objectives are to improve the transient and voltage stability of the inter-connected system. The nonlinear approach is based on the zero dynamics technique. The effectiveness of the proposed approach was evaluated via eigenvalue analysis and transient simulations. Further assessments of its dynamic performance were performed by considering a three phase fault condition. The obtained results were compared to that of a traditional power oscillation damping (PRINT) approach. Significant improvements in the transient behavior and power stability of the inter-connected power system are among the main positive features of the proposed design.