Session: 09-05-04 Wave Energy: Power Take Off Systems

Submission Number: 181476

The Study of Power Take-Off System Sizing for Wave Energy Converter Array 

With the development of wave energy converters (WECs), large-scale commercialization of these technologies is expected in the near future. To achieve higher power capacity targets, WECs will need to be deployed in arrays. Since a WEC array typically consists of multiple individual converters within a relatively limited offshore area, the hydrodynamic interactions among WECs have garnered significant research attention. Studies have shown that these interactions impact factors such as array configuration, the geometric shape of the WECs, and the size of WEC buoys. As a core component of WECs, Power Take-Off (PTO) systems are crucial not only for influencing the dynamic response of the WEC but also in terms of economic cost. Proper PTO sizing has been shown to reduce costs for standalone WEC systems, yet studies on PTO sizing have not yet extended to array-scale deployments. The primary objective of this work is to explore the interplay between PTO sizing, WEC array configuration, and the techno-economic performance of WEC arrays.

In this study, we define the reference WEC array as five individual heaving point absorbers. The array's hydrodynamics are predicted numerically using an open-source boundary element method tool, Nemoh. Here, the PTO size is represented by the maximum force the system can provide. Since PTO force capping introduces nonlinear effects, we use a spectral-domain model approach to simulate the behavior of the WEC array, incorporating force capping nonlinearity through statistical linearization. Additionally, a preliminary economic model is developed to evaluate the costs of WECs with varying PTO sizes. To assess how configuration affects PTO sizing, three typical WEC array configurations are examined, allowing for the comparison of optimal PTO sizes of each WEC across different configurations. Finally, this study reveals the impact of PTO sizing within WEC arrays on improving overall techno-economic performance, that levelized cost of energy in this work.

 

 

Presenting Author: Jian Tan Delft University of Technology

Presenting Author Biography: Dr. Jian Tan is a Post-Doctoral Fellow at the Offhsore Engineering group. Jian obtained his PhD from TU Delft in 2022. His research is focused on the design and development of wave energy converters, including spectral-domain modeling, wave-to-wire analysis, and PTO systems.

Authors:

Jian Tan Delft University of Technology
Chen Xi Zhejiang University
Avni Jain Delft University of Technology
George Lavidas Delft University of Technology
Hongyi Jiang Zhejiang University
Zhen Guo Zhejiang University