Inertial and primary frequency response model of variable-speed wind turbines

Increase of converter-connected renewable power generation such as variable-speed wind turbines (VSWTs) decreases the system inertia constant, which reduces the frequency stability of the power system. Thus, it will be necessary to include these renewables in the inertial response and primary frequency control (PFC) of future power systems. In this study, the participation of VSWTs in frequency support is studied. First, the importance of inertial response and PFC is discussed. Then, the linearised model of VSWT with inertial and primary frequency response capabilities is presented and compared against the non-linear model. Finally, this model is integrated in a system frequency response model that consists of various power plants. Different operational scenarios are simulated to investigate the impact of wind turbines with and without emulated inertia and primary frequency response on frequency stability.