Abstract
Experimental tank testing of wave energy converters (WECs) with representative mooring systems is challenging due to scaling limitations and the difficulty of reproducing full-scale, highly dynamic mooring loads in laboratory environments. Real-time hybrid simulation (RTHS) is a viable method to accelerate WEC development; however, its application to WEC-mooring interaction remains limited by communication delays, force-tracking challenges, and synchronization requirements between numerical and physical domains. This work develops and experimentally tests a mooring-focused RTHS framework for scaled WEC testing. A multi-stage framework is proposed: (1) physics-based hydrodynamic modeling for characterization of WEC dynamics; (2) software-only virtual RTHS for controller and filter development; and (3) physical implementation on a single-DOF linear test bed (LTB) with hardware-in-the-loop actuation to evaluate real-time performance under realistic actuator dynamics, system delays, and measurement noise. Two RTHS configurations are evaluated using the LTB. A single-loop configuration isolates mooring load, demonstrating dynamic force reproduction with less than 1.5% RMS error and delays below 10 ms. A dual-loop configuration incorporates reactive, nonlinear body dynamics, resulting in RMS errors just under 3%. Results show that the framework can emulate mooring forces under regular wave conditions while maintaining stable real-time operation, enabling earlier, lower-cost investigation of WEC–mooring interactions.