A new adaptive control is formulated for the pitch control of wind turbine with structural uncertainties.
The controller makes a trade-off between the maximum energy captured and the load induced.
The controller is designed to regulate generator speed and to mitigate component loads under turbulent wind field.
Case studies show that the blade root flapwise load can indeed be reduced at a slight expense of optimal power output.
In this research, a new adaptive control strategy is formulated for the pitch control of wind turbine that may suffer from reduced life owing to extreme loads and fatigue when operated under high wind speed and internal structural uncertainties. Specifically, we aim at making a trade-off between the maximum energy captured and the load induced. The adaptive controller is designed to both regulate generator speed and mitigate component loads under turbulent wind field when blade stiffness uncertainties exist. The proposed algorithm is tested on the NREL offshore 5-MW benchmark wind turbine. The control performance is compared with those of the gain scheduled proportional integral (GSPI) control and the disturbance accommodating control (DAC) that are used as baselines. The results show that with the proposed adaptive control the blade root flapwise load can be reduced at a slight expense of optimal power output. Moreover, the blade load mitigation performance under uncertain blade stiffness reduction is improved over the baseline controllers. The control approach developed in this research is general, and can be extended to mitigating loads on other components.
- Wind turbine;
- Pitch control;
- Load mitigation;
- Adaptive control;
- Turbulent wind field;
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