Recent work demonstrated the benefits of preview wind measurements for turbine control. This paper investigates the basic design tradeoffs between turbine performance, preview time, and pitch actuator rate limits. A Region 3 rotor-speed tracking problem is formulated in continuous-time as an optimal control problem using a simple one-state rigid body turbine model. The exact analytical solution to this problem provides insight into the fundamental performance limits. These analytical results are compared with the performance of an H∞ preview controller simulated on a higher fidelity, nonlinear turbine model with realistic wind sensor models. The performance versus preview time characteristics of the H∞ controllers are in agreement with the predictions from the lower fidelity model. Thus, the analytical results obtained with the low-order model can provide design guidelines for the use of preview information in turbine control.
- Preview control
- wind turbines