Nonlinear Model Predictive Control Based on Real-Time Iteration Scheme for Wave Energy Converters Using WEC-Sim

Guerrero-Fernandez, Juan Luis; Tom, Nathan Michael (ORCID:000000028489312X); Rossiter, John Anthony

doi:10.1115/omae2022-80972

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DOE OSTI · 1900022

Nonlinear Model Predictive Control Based on Real-Time Iteration Scheme for Wave Energy Converters Using WEC-Sim

Guerrero-Fernandez, Juan Luis·Tom, Nathan Michael (ORCID:000000028489312X)·Rossiter, John Anthony

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Abstract

One of several challenges that wave energy technologies face is their inability to generate electricity cost-competitively with other grid-scale energy generation sources. Several studies have identified two approaches to lower the levelised cost of electricity: reduce the cost over the device's lifetime or increase its overall electrical energy production. Several advanced control strategies have been developed to address the latter. However, only a few take into account the overall efficiency of the power take-off (PTO) system, and none of them solve the optimisation problem that arises at each sampling time on real-time. In this paper, a detailed Nonlinear model predictive control (NMPC) approach based on the real-time iteration (RTI) scheme is presented, and the controller performance is evaluated using a time-domain hydrodynamics model (WEC-Sim). The proposed control law incorporates the PTO system's efficiency in a control law to maximise the energy extracted. The study also revealed that RTI-NMPC clearly outperforms a simple resistive controller.

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Guerrero-Fernandez, Juan Luis, Tom, Nathan Michael (ORCID:000000028489312X), Rossiter, John Anthony. 2022-10-13. Nonlinear Model Predictive Control Based on Real-Time Iteration Scheme for Wave Energy Converters Using WEC-Sim. https://doi.org/10.1115/omae2022-80972

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