MULTI-OBJECTIVE ROBUST OPTIMIZATION DESIGN OF A FIXED-SPEED HORIZONTAL AXIS WIND TURBINE

The produced power and the thrust force exerted on the wind turbine are two conflicting objectives in the design of a floating horizontal axis wind turbine. Meanwhile, the variations in design variables and design environment parameters are unavoidable. The variations include the small variations in the design variables due to manufacturing errors, and the large variations in the wind speed. Therefore, two robustness indices are introduced in this paper. The first one characterizes the robustness of multi-objective optimization problems against small variations in the design variables and the design environment parameters. The second robustness index characterizes the robustness of multi-objective optimization problems against large variations in the design environment parameters. The robustness of the solutions based on the two robustness indices is treated as a vector defined in the robustness function space. As a result, the designer can compare the robustness of all Pareto optimal solutions and make a decision. Finally, the multi-objective robust optimization design of a fixed-speed horizontal axis wind turbine illustrates the proposed methodology.