Nonlinear Control for a Single Phase Grid Connected Wind Energy System

The subject of this article is related to the problem of controlling the wind energy conversion system connected to the single-phase grid. The considered system consists of a wind turbine with a permanent magnet synchronous generator (PMSG), a three-phase uncontrolled rectifier, a buck-boost converter, and finally a single-phase inverter with an LCL filter. The purposes of the developed controller are: 1) extracting the maximum power from wind; 2) Regulating the DC link voltage at a constant value; 3) Correcting the power factor in order to eliminate the phase difference between the voltage and current of the grid and ensure that the produced current is sinusoidal. The wind energy conversion structure is detailed by a 6th-order mathematical model and regulated with two nonlinear techniques, namely sliding mode control (SMC) and integral sliding mode control (ISMC). The robustness and efficiency of the developed control strategy with respect to the change of the wind speed are proved by simulation in the Matlab/Simulink environment.