Input-to-State Stability Based Control of Doubly Fed Wind Generator

This paper proposes a novel approach on controller design for a doubly fed wind generator based on input-to-state stability (ISS) theory. In order to guarantee the stability of the nonlinear system with external disturbances, a systematic methodology for constructing locally ISS stabilizing (LISS) control Lyapunov functions and designing the corresponding robust LISS control law is proposed. This method avoids the Hamilton-Jacobi-Isaacs (HJI) partial differential equation and the limitation of exact linearization. The proposed ISS control law is proved to be inverse optimal and can guarantee the stability of the wind generation system under external disturbances. The simulation studies verify the effectiveness of the proposed ISS controller. Compared with conventional proportional-integral (PI) controllers, and exact linearization-based nonlinear controllers, the proposed ISS controller has the ability to enhance the transient stability of the wind generation system during and after faults, and can significantly improve the dynamic performance of the system.