Discretization modeling with pseudo real-time waves input of the hybrid wave-tidal energy converter based on non-linear motions rectification and coupling device

The discretization modeling methodology is proposed for dynamic analysis of Hybrid Wave-Tidal Energy Converters (HWTEC). By integrating the Pseudo Real-Time Wave (PRTW) simulation method based on random wave theory, it effectively reflects the actual random ocean waves characteristics and addresses the nonlinear response, without relying on continuous inputs. The discretization modeling method precisely determines and calculates the nonlinear dynamic response during the overrunning phase, enabling direct numerical solutions for nonlinear input and output parameters in the time domain, and eliminating the need for complex manual judgments. Validation through re-simulation of previous work shows an acceptable error of approximately 5 % in input and 0.5 % in output, demonstrating reliability. The proposed hybrid wave-tidal energy converter, based on the Non-Linear Motions Rectification and Coupling Device (NLMRCD), converts reciprocating wave motion into one-way motion and couples it with tidal rotation to enhance power output. It leverages the complementary and asynchronous distribution of wave and tidal energies, resulting in more stable output. Simulations reveal the impact of key parameters on output power and efficiency, achieving an average output power of 206.2 W and an efficiency of 40.8 %. The overrunning phase increases output power by 54.0 %, significantly enhancing output stability.