Floating offshore wind turbine (FOWT) technology today has a high cost compared with fixed-base offshore or onshore wind turbine technology and is therefore not an economically attractive renewable energy resource. A primary cause of these economics is that the main components of state-of-the-art FOWTs—the turbine and the floating platform—are designed independently. Currently, floating platforms are designed to be large and heavy so that the wind turbine performs as if it were installed on a fixed base. Supported by the ARPA-e ATLANTIS program, GE Research and Glosten, Inc., are collaborating to take a radically different approach to design a 12 MW light weight FOWT. The weight reductions are achieved through a process of control co-design, platform actuation, and system optimization, which we approach in this effort in three steps.
In the first step, a baseline FOWT turbine is sized, modeled, and simulated, by integrating an offshore wind turbine alike GE’s Haliade X 12 MW turbine with Glosten’s PelaStar tension leg floating (TLP) platform design. This baseline turbine serves multiple purposes. It provides a benchmark for performance and cost metrics of a state-of-the-art FOWT design. Moreover, it gives insight in key system-level design-driving dynamics, which are used in the second step. In this step, the advanced control algorithms that operate the turbine are designed concurrently with the integrated structure of the FOWT. Active tendon control will be considered to enhance the controllability of the platform dynamics. The concurrent design of structure and controls will eliminate conservatism and suboptimality of the closed-loop dynamics, resulting in lower mass of key subsystems, like tower and platform. Pursuing further Levelized Cost of Energy (LCOE) optimality in step 3, a system-level approach is taken to numerically optimize the system dynamics and component interactions by simultaneous optimization of parameters of the FOWT design and the controls.
This project fits in the strategy of GE to develop competitive Floating Offshore Wind solutions, for which innovations are needed in the combination and integration of wind turbine technology with the variety of today’s existing floating platform technologies. The proposed design in this TLP-focused project achieves aggressive mass reductions in the platform and tower of over 35% compared to state-of-the-art FOWT designs, with a potential reduction of the resulting LCOE of more than 20% compared to the baseline.
Capabilities utilized for Control Co-design of Floating Offshore Wind Turbines project
Developing advanced multi-variable model-based control algorithms that leverage online models to provide stability and improve transient performance and operabilityRead more
Estimation & Modeling
Developing novel models for real-time use in controls, estimation and optimizationRead more