Finite Frequency H∞ Control for Doubly Fed Induction Generators with Input Delay and Gain Disturbance

Abstract

Due to the rapid development of wind power, the stable operation of doubly fed induction generators (DFIGs) has attracted much attention. This paper focuses on the finite frequency (FF) H∞ control for the DFIG with input delay, aiming to reduce the effects of current harmonic interferences and gain disturbances on the DFIG and improve the stability of the system. First, a DFIG state–space model with input delay under current harmonics was constructed. Second, based on the DFIG state–space model, an FF H∞ state-feedback controller was designed from the frequency domain perspective, which makes the DFIG stable and robust against harmonic interferences and gain disturbances. Third, via the generalized Kalman–Yakubovich–Popov (GKYP) lemma and the Lyapunov theory, the FF H∞ performance was evaluated in the form of linear matrix inequalities (LMIs), and then the state feedback FF H∞ controller was designed. Finally, the simulation results showed the efficiency of the proposed approach.