Impact of large-scale wind penetration on transient frequency stability

Wind turbines such as doubly-fed induction generator (DFIG) are widely used in modern power system. Wind turbines are restricted to operate in a smaller range of frequency deviation than steam turbines. Increasing wind penetration decreases system inertia and worsens system frequency response. Mechanism of transient frequency stability (TFS) is discussed and a TFS index is proposed in this paper. Impact of wind penetration on TFS critical disturbance is analyzed on a provincial power system of China. Maximum wind penetration is calculated with TFS index. Spinning reserve and underfrequency load shedding (UFLS) are used to improve system TFS. Simulations show that TFS should be taken seriously for system with large-scale wind penetration.