Performance Comparison of Variable Speed PMSG-based Wind Energy Conversion System Control Algorithms

This paper presents a comparative analysis of three control algorithms for a wind turbine generator using a variable speed permanent magnet synchronous generator (PMSG). The design methodologies of the conventional PI-based controller, the Taylor series expansion linear approximation based (TSLA-based) controller and the feedback linearization based (FL-based) nonlinear controller are provided. The objective is to keep the wind turbine operating at its optimum rotor speed (MPPT control), while insuring the power transfer from the turbine to the generator, regardless of the wind speed. The controller gains of the nonlinear controller are determined via Linear Quadratic Optimal Control (LQOC) approach. The results show a better control performance for the nonlinear controller. This performance is characterized by fast and smooth transient responses as well as a zero steady state error and reference tracking quality.