Abstract
The Hawaiʻi Marine Energy Center (HMEC) is actively investigating high-flow hydraulic pump characteristics for oscillating wave surge energy converter (OWSEC) applications. The motivation for this research stems from previous lessons learned during the Hawaiʻi Wave Surge Energy Converter (HAWSEC) project. Bound by off-the-shelf constraints, the initial high-flow variant of the HAWSEC power take-off (PTO) system resulted in suboptimal performance due to insufficient flow rates and higher-than-expected energy reflection. While high-flow PTOs have been theorized to reduce energy dissipation compared to high-head systems, initial efforts supporting this hypothesis were inconclusive.
By removing off-the-shelf component constraints, this research explores the potential for a fully optimized high-flow hydraulic pump that minimizes energy losses. To achieve this, a co-design methodology is employed using a linear impedance model of the pump to optimize energy throughput. This approach allows for a systematic investigation of the dynamic interactions between the hydraulic pump and the wave collector, ensuring optimal impedance matching for efficient power transfer.
The study further validates the linear impedance model by comparing its performance with a fully coupled nonlinear Simscape-WECSim model. This comparison extends the fidelity of the linear modeling approach by capturing the complex dynamics of the high-flow hydraulic system and provides more accurate PTO power projections.
This research contributes to the ongoing development of wave energy technologies in the community by presenting preliminary findings on an optimized high-flow hydraulic pump that addresses previous limitations encountered with off-the-shelf components. Future work will focus on experimental validation of the optimized design and further refinement of modeling techniques to enhance predictive accuracy.