Coordinated control parameter setting of DFIG wind farms with virtual inertia control

Abstract

Power systems with high penetration of renewables have low natural inertia and require alternative inertia support. For the natural inertia on the rotor, wind farms are expected to be an ideal choice to provide inertia response. However, virtual inertia may interfere with the small-signal stability of power systems. To guarantee both the frequency stability and the small-signal stability of power systems, taking doubly-fed induction generator (DFIG) as an example, a coordinated control parameter setting method of wind farms with virtual inertia control is proposed. An optimization model of control parameters is established. The damping ratio of the eigenvalue is set as the objective function to improve the small-signal stability. Besides, the inertia-dependent frequency constraints are considered in the optimization model to ensure the frequency stability. To solve the optimization model, a Newton-based eigenvalue optimization algorithm with the inertia-dependent frequency constraints is proposed based on the sensitivity analysis. Case studies demonstrate that the proposed method can effectively guide the control parameter setting of wind farms to ensure the frequency stability and improve the small-signal stability at the same time.