Fuzzy reference model $H_{\infty}$ integral fuzzy maximum power tracking of WECS based-on DFIG

This paper presents a new fuzzy control design for maximum power point tracking (MPPT) of wind energy conversion systems (WECS) using a doubly fed induction generator (DFIG) based on
$H_{\infty}$
optimal control. In the first place, a new nonlinear reference model is developed for describing the optimal dynamic of the doubly fed induction generator (DFIG). In the second place, the nonlinear dynamic behaviour of the real system and its reference model are represented by a Takagi-Sugeno (TS) fuzzy model. Then, using a fuzzy proportional integral state feedback controller, a novel MPPT strategy for DFIG-based wind energy conversion systems is investigated. The
$H_{\infty}$
criteria performance is used to design a robust fuzzy proportional integral state controller under varying wind speed. The
$H_{\infty}$
stabilisation conditions are generated and given in terms of linear matrix inequalities (LMI). The estimation of the largest set invariance conditions are proposed as a LMI convex optimization problem. Finally, simulation results show that the proposed fuzzy integral state controller gives a good disturbance rejection and MPPT rapid convergence in the presence of wind's gusts.