Date of Award


Document Type

Open Access Master's Report

Degree Name

Master of Science in Mechanical Engineering (MS)

Administrative Home Department

Department of Mechanical Engineering-Engineering Mechanics

Advisor 1

Gordon G Parker

Committee Member 1

Chee-Wooi Ten

Committee Member 2

Wayne W. Weaver


In this report model predictive control (MPC) is applied to a simulated, spherical, point absorber wave energy converter to maximize energy extraction. Constraints are applied to the buoy's displacement and the power take-off (PTO) generator force. The WEC's "truth” model uses nonlinear Froude-Krylov (FK) hydrostatic and hydrodynamic forces. This is in contrast with previous studies where linear approximations are used in the form of a hydrostatic stiffness force and a wave excitation force. The nonlinear forces become significant when the vertical displacement of the buoy exceeds about 40% of the buoy's radius. Two versions of MPC are compared where optimal PTO forces are calculated based on (1) a linear model, called LMPC, and (2) the nonlinear model, called NLMPC. For the cases considered, the energy absorbed using NLMPC is greater than for LMPC. Furthermore, the linear MPC solution, when applied to the truth model.