Multi-objective optimization of wind turbine via controllers coordination and sensitivity analysis

In this paper, a sensitivity-analysis-based wind turbine optimization strategy is introduced to improve the power output stability while reducing the shaft and tower loads. Both generator torque and blade pitch are controlled coordinately to achieve the optimization. During the wind turbine control process, blade pitch and generator torque are controlled proportionally to the generator speed tracking error, which simplifies the controller structure, thus, the wind turbine performance can be evaluated with control variables sensitivities directly. The wind turbine performance is considered in output power stability, shaft bending moment and tower bending moment. Both load parameters are analysed in fatigue damage lifetime. A conflicting relationship is realized between the load-power characteristic during the optimization, and a global coordination solution is selected on the pareto optimal frontier. Essential, this work is an exploration for the quantitative analysis from the wind turbine load performance to the control variables sensitivities directly without the limitation of controller forms. Simulation results show the effectiveness of the proposed controller.