Fault-tolerant load frequency control for DFIG-based interconnected wind power systems

Abstract

This paper investigates the fault-tolerant load frequency control (LFC) design of interconnected wind power systems. For this, a doubly-fed induction generator (DFIG)-based wind farm is integrated into the interconnected power systems. Distinct from the existing works, the communication time-delay is taken into the area control error (ACE) signals of interconnected wind power systems. Also, compared with the traditional LFC scheme, a fault-tolerant H∞ LFC scheme is presented with known and unknown actuator fault against load disturbances and wind speed fluctuations. Then, the asymptotic stability conditions are derived in the linear matrix inequalities (LMIs) form by utilizing the Lyapunov–Krasovskii functional (LKF) method and Wirtinger-based inequality technique under the designed LFC scheme with H∞ performance. Finally, numerical examples are given to validate the applicability and superiority of the designed LFC scheme.