Design of a Nonlinear Robust Adaptive Controller for a Grid-Connected Doubly-Fed Induction Generator Wind Turbine

A robust adaptive nonlinear controller is designed for a Doubly-Fed Induction Generator (DFIG) wind turbine supplying a power grid. The controller main objective is to guarantee that the generator active and reactive power are kept constant despite grid voltage and frequency variations. A model based control design method is proposed. The controller structure and equations are obtained following a backstepping control design method using the DFIG reduced order model. Grid parameters are assumed unknown during the design. Therefore the controller is provided with an adaptation module that readjusts automatically controller parameters when the grid condition changes. Simulations are used to assess the proposed DFIG controller effectiveness.