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From TPL Assessment to Design Optimization: Wave Energy Converter Control Co-Design Applied to the RM3

Journal Article · · Renewable Energy

The Reference Model (RM) project developed six marine energy converter concepts using a sequential design methodology, which, while widely adopted in the industry, often overlooks interactions between system components, resulting in suboptimal designs. One such example is the Reference Model 3 (RM3), a two-body point absorber wave energy converter (WEC). An assessment using the Technology Performance Level (TPL) revealed that RM3's low power-to-cost ratio, partly due to expensive steel construction, limits its techno-economic performance. This study aims to redesign RM3 by reducing its scale and employing control co-design to integrate WEC and Power Take-Off (PTO) dynamics, constraints, and cost considerations within an optimization framework. We demonstrate the limitations of RM3's current PTO design and explore the benefits of scaling down to enhance techno-economic viability by lowering material costs. Using WecOptTool, we conduct a parameter sweep over gear ratios and spring stiffnesses for various Commercial Off-The-Shelf generators in irregular wave conditions. Our findings emphasize the importance of aligning PTO components with WEC dynamics, showing that control co-design and strategic scaling can improve RM3's power-to-cost ratio. This study presents a transferable example of applied control co-design for other WECs, supporting early-stage developers in their design decisions.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Renewable Power Office. Water Power Technologies Office
DOE Contract Number:
AC36-08GO28308
OSTI ID:
2525868
Report Number(s):
NREL/JA-5700-92861; MainId:94643; UUID:14544568-4ed0-41b9-a508-04f974e975df; MainAdminId:75949
Journal Information:
Renewable Energy, Journal Name: Renewable Energy Vol. 241
Country of Publication:
United States
Language:
English

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