Dynamic voltage stability analysis of IEEE 9-bus system integrated with a double fed induction generator wind farm

The growing penetration of wind power, particularly through Doubly-Fed Induction Generators (DFIGs), significantly presents both opportunities and challenges for modern power systems. Despite the operational benefits of renewable generation, the inherent variability and converter-interfaced nature of DFIGs reduce the system’s equivalent inertia and its short-circuit power contribution, thereby challenging conventional voltage regulation and transient stability mechanisms. This study investigates the impact of DFIG-based wind farm integration on the voltage stability of the IEEE 3-machines 9-bus test system, with a focus on post-disturbance dynamic behavior. The analysis is conducted under a severe symmetrical three-phase fault applied to line 5–7, in near Bus 7. Using time-domain simulations in MATLAB/Simulink, the study assesses voltage recovery profiles, fault-induced voltage deviations, and the dynamic exchange of active and reactive power. The results indicate that the severity of the voltage transient and the subsequent recovery trajectory are highly dependent on the electrical distance from the fault location and the availability of dynamic reactive power support from both the wind farm and the network. Moreover, after fault clearance, a distinct voltage recovery period is required to restore prefault operating conditions, highlighting the role of dynamic voltage stability in systems with high penetrations of converter-interfaced generation.