The plain of El-Outaya is located in arid zone of the Saharan Atlas in southern Algeria. The groundwater are characterized by an Important and variability of the salinity. The geology indicates that the plain is constituted by evaporitic rocks. The Dj. El Melah (trias) takes a very important place in the geology of the plain by its lithological composition and its abnormal contacts with the formations around.  Evaporation in the area is very important and consumes the majority of the precipitations.  The heterogeneity of the aquifer of neogene is caused by the presence of clay in variable proportions. The combination between the tools, geological, hydrodynamic, statistical and chemical in the study of the mineralisation allowed us to determine its origin and its evolution in the space.  The analysis of groundwater samples indicates the presence in strong concentrations of Cl-, SO42-, Na+ and Mg2+.

This paper discusses the robust control of a grid-connected doubly-fed induction generator (DFIG) controlled by vector control using a nonlinear feedback linearization strategy in order to ameliorate the performances of the control and to govern the developed stator active and reactive power in a linear and decoupled manner, in which an optimal operation of the DFIG in subsynchronous operation is given, as well as the control stator power flow with the possibility of keeping stator power factor at a unity. The use of the state-all-flux induction machine model gives place to a simpler control model. So, to achieve this objective, the Lyapunov approach is used associated with a sliding mode control to guarantee the global asymptotical stability and the robustness of the parametric variations.