Coordinated Control of Doubley Fed Induction Generator Virtual Inertia and Power System Oscillation Damping Using Fuzzy Logic

Doubly-fed induction generator (DFIG) based wind turbines with traditional maximum power point tracking (MPPT) control provide no inertia response under system frequency events. Recently, the DFIG wind turbines have been equipped with virtual inertia controller (VIC) for supporting power system frequency stability. However, the conventional VICs with fixed gain have negative effects on inter-area oscillations of regional networks. To cope with this drawback, this paper proposes a novel adaptive VIC to improve both the inter-area oscillations and frequency stability. In the proposed scheme, the gain of VIC is dynamically adjusted using fuzzy logic. The effectiveness and control performance of the adaptive fuzzy VIC is evaluated under different frequency events such as loss of generation, short circuit disturbance with load shedding. The simulation studies are performed on a generic two-area network integrated with a DFIG wind farm and the comparative results are presented between three cases: DFIG without VIC, DFIG with fixed gain VIC, and DFIG with adaptive fuzzy VIC. All the results confirm the proposed fuzzy VIC can improve both the inter-area oscillations and frequency stability.