Sensorless nonlinear control based on integral backstepping technique for PMSG- based wind energy conversion system

Abstract

This article addresses the control of the wind energy conversion system (WECS) based on a permanent magnet synchronous generator (PMSG) connected to the grid through a three-phase rectifier and an inverter followed by an L filter. Two observers have been developed to estimate the mechanical torque of the PMSG and the rotor flux. Integral backstepping control (IBC) has been employed to regulate the wind energy conversion system. Its objective is to achieve maximum power point tracking while maintaining the bus voltage at its reference and regulating the injected power into the grid to ensure a unity power factor. The developed control approach has been tested using Matlab/Simulink and compared with the linear PI controller. Simulation results demonstrate, on one hand, the robustness, efficiency, and superiority of the nonlinear technique employed, and on the other hand, the dynamic performance of the developed observers.