Impact of wind generation mix on transient stability for an interconnected power system

The rapid growth of wind generation in many European countries is pushing power systems into uncharted territory. As additional wind generators are installed, the changing generation mix may impact on power system stability. This paper adopts the New England 39 bus system as a test system for transient stability analysis. Thermal generator models are based on a likely future plant mix for existing systems, while varying capacities of fixed-speed induction generators (FSIG) and doubly-fed induction generators (DFIG) are considered. The main emphasis here has been placed on the impact of wind technology mix on inter-area oscillations following transient grid disturbances. In addition, both rotor angle stability and transient voltage stability are examined, and results are compared with current grid code requirements and standards. Results have shown that FSIGs can reduce tie-line oscillations and improve damping following a transient disturbance, but they also cause voltage stability and rotor angle stability problems at high wind penetrations. In contrast, DFIGs can improve both voltage and rotor angle stability, but their power output noticeably oscillates during disturbances.