Wind farms generation limits and its impact in real-time voltage stability assessment

This paper proposes a method to consider the impact of the wind farms maximum current limits on real-time voltage stability assessment. The approach is based in a multi-port equivalent of the system which makes possible to assess the effect of each wind farm limit on the stability boundary, the approach indicates the distance to the limit activation and the effect of each load in such a limit. The wind farm control schemes includes voltage control and it is represented as a constant current at its limit. A criteria to select the critical bus bar, based on the generator transformation coefficients, is presented. This methodology is tested in a platform that produces synthesized PMU measurements from time-domain simulations and critical boundary for the wind-farm limits are shown. The methodology is also tested for synchronous machines and its parallel structure is exploited when implemented in a High Performance Computing environment. A computational time under 2ms shows that the method is suitable for real-time applications.