Evaluating Methods for Control of an Offshore Floating Turbine

Developing wind turbines on floating offshore platforms is a topic of growing interest. By using a floating platform, wind turbines can be located in areas with good resources and near to major load centers. However, there can be technical challenges with this approach, and one is the observed unstable interaction between the pitch speed controller and the platform motions. In this paper, we consider several controls-based methods for resolving this issue for a commercial-scale turbine on a tension-leg platform. The design of each method is reviewed and each is shown to resolve the unstable interaction. The methods are then compared through load suite analysis to assess the strengths and weaknesses of each approach. Finally, we present proposals for refining and combining these methods and further approaches for performance improvement that could be considered.Copyright © 2014 by ASME and Alstom Power Inc.