Modeling and validation of a small heave plate wave energy converter

• Developed a simplified lumped-parameter model for small heave plate WECs. • Validated model predictions against extensive experimental data. • The simplified model captured key WEC dynamics efficiently. • Linked laboratory behavior to ocean-relevant operational conditions. Wave energy converters (WECs) are increasingly being adapted for smaller-scale applications, such as powering unmanned oceangoing vehicles. For free-floating ocean platforms, there is a need for a simplified modeling framework that can be efficiently applied and used as a foundation for future optimization and design insight. We present the development and validation of a lumped-parameter model representative of a small heave plate WEC designed for short-period waves (1-5 s) typical of moderate wind conditions. The modeled system consists of a negatively buoyant drag plate and a surface buoy connected by a spring-damper power take-off (PTO) that captures the relative motion between the two bodies. To validate the model, a physical prototype of the heave plate WEC was constructed. A linear actuator simulated wave excitation, replicating the idealized vertical forcing experienced by a buoy in a wave field. Experiments varied wave conditions, system mass, and PTO parameters to assess their influence on the model and measured response. Results show that lower non-dimensional spring constants ( K *) improve broadband performance, while higher non-dimensional masses ( M *) yield only marginal increases in mean power. These findings confirm the model’s accuracy and provide guidance for optimizing WEC design for free-floating platforms.