Background

The typical wind turbine design process is sequential, where the turbine is first designed considering aerodynamic and structural aspects of the turbine’s blades using conservative estimates for structural loading and power capture. Once the model is finalized, only then is a controller developed to simulate realistic environments that the wind turbine must survive to be a feasible design. Typically, controllers are designed to mitigate issues or enable future design targets. However, if the effects of closed-loop control are accounted for during the design process, e.g., using a load reducing controller to design lighter blades, or by increasing power capture while still satisfying design constraints, the cost of wind energy can be reduced.

Technology Overview

Instead of using a single cost function that attempts to account for all aspects of wind turbine design, the technology developed by researchers at the University of Colorado Boulder solves specific wind turbine control problems that are directly related to the cost of energy. Firstly, the optimization procedure is demonstrated on below-rated torque control to increase power capture. Next, the pitch control parameters for above-rated pitch control are optimized to reduce fatigue or extreme loads on the tower or blades with a maximum generator speed constraint. Finally, the overall controller adapts to be “greedier” when conditions allow for it and to be “safer” when necessary.

Stage of Development

Technology Readiness Level (TRL): 5

Benefits

Increased power output
Increased revenue
Reduced chance of wind turbine shutdowns at great wind speeds
More dynamic controller

Applications

New wind turbines
Software update for existing wind turbines

Load Constrained Power Reference Control for Wind Turbines