LQR Control for a Multi-MW Wind Turbine

This paper addresses linear quadratic regulation (LQR) for variable speed variable pitch wind turbines. Because of the inherent nonlinearity of wind turbine, a set of operating conditions is identified and then a LQR controller is designed for each operating point. The feedback controller gains are then interpolated linearly to get control law for the entire operating region. Besides, the aerodynamic torque and effective wind speed are estimated online to get the gain-scheduling variable for implementing the controller. The potential of the method is verified through simulation with the help of MATLAB/Simulink and GH Bladed. The performance and mechanical load when using LQR are also compared with that when using PI controller.

Authors:

• Trung-Kien Pham
• Yoonsu Nam
• Hyungun Kim
• Jaehoon Son

Keywords:

• variable speed variable pitch wind turbine
• multi-MW size wind turbine
• wind energy conversion system
• LQR control.

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