[01] John Sami, Department of Mechanical Engineering, University of Western Australia, Perth, Australia. [02] Karim Khalil, Department of Mechanical Engineering, University of Western Australia, Perth, Australia.

A small scale wind turbine blade is studied using blade element momentum (BEM) theory. A difficult goal in the implementation of the BEM theory is the correct representation of the lift and drag coefficients at post-stall regime. A method based on the Viterna equations is implemented for producing airfoil data at the post-stall regime and results are compared with various mathematical models. Results showed the high capability of this method to predict the lift and drag coefficients for airfoils, resulting in better power curve estimation. The implemented model for wind turbine load estimation is applied for a the variable-speed variable-pitch (VSVP) wind turbine and the results show a considerably increased in turbine annual energy production (AEP) about 16.78% compared with the NREL phase VI turbine.

Variable-Speed Variable-pitch Wind Turbine, BEM Theory, Annual Energy Production, Post-stall Region

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