Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Numerical Analysis on Hydraulic Power Take-Off for Wave Energy Converter and Power Smoothing Methods

Conference ·
 [1];  [1];  [1]
  1. National Renewable Energy Laboratory (NREL), Golden, CO (United States)
One of the primary challenges for wave energy converter (WEC) systems is the fluctuating nature of wave resources, which require the WEC components to be designed to handle loads (i.e., torques, forces, and powers) that are many times greater than the average load. This approach requires a much greater power take-off (PTO) capacity than the average power output and indicates a higher cost for the PTO. Moreover, additional design requirements, such as battery storage, are needed, particularly for practical electrical grid connection, and can be a problem for sensitive equipment (e.g., radar, computing devices, and sensors). Therefore, it is essential to investigate potential methodologies to reduce the overall power fluctuation while trying to optimize the power output from WECs. In this study, a detailed hydraulic PTO model was developed and coupled with a time-domain hydrodynamics model (WEC-Sim) to evaluate the PTO efficiency for WECs and the trade-off between power output and fluctuation using different power smoothing methods, including energy storage, pressure relief mechanism, and a power-based setpoint control method. The study also revealed that the maximum power fluctuation for WECs can be significantly reduced by one order of magnitude when these power smoothing methods are applied.
Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Wind and Water Technologies Office (EE-4W)
DOE Contract Number:
AC36-08GO28308
OSTI ID:
1482885
Report Number(s):
NREL/CP-5000-72834
Country of Publication:
United States
Language:
English