Backstepping based MPPT Control Technique for Permanent Magnet Synchronous Generator Wind Energy Conversion System

The unpredictable and stochastic speed of the wind makes the entire wind energy conversion system (WECS) highly nonlinear. In such situations, the controller aim is to maximize the extracted power (MP). At first stage, the dynamic model of the permanent magnet synchronous generator (PMSG) is developed and then the model is converted to Bronwsky form. Consequently, the overall system is subdivided into two subsystems i.e., a second order visible dynamic system and a first order internal dynamic system. The internal dynamics are proved stable i.e., the system under study is minimum phase. Now, the main task is that the output of the visible dynamic system should track a varying profile of the wind speed. This paper presents the nonlinear backstepping based maximum power point tracking (MPPT) algorithm to ensure the MP extraction from variable-speed (fixed pitch) WECS. MATLAB/Simulink tool is used for testing the proposed controller under variable wind speed profile. The simulation results validate the robustness of the proposed control scheme. Furthermore, backstepping is compared with feedback linearization (FL) control that clearly outshines our proposed strategy.