A Vessel Propulsion Controller based on Economic Model Predictive Control

The importance of reducing energy expenditure in vessel propulsion is underlined by recent environmental mandates in the maritime sector. Vessel propulsion is a multi-objective problem, since the overall energy expenditure of the powertrain must be minimized, while the vessel speed must be maximized. This paper proposes an economic model predictive control (EMPC) approach, which can accommodate powertrain efficiency maps and thus evaluate candidate input trajectories in terms of energy efficiency. The proposed EMPC controller utilizes recent theoretical developments in order to guarantee stability. Simulation results are presented in comparison to a standard MPC scheme, for two different vessel sizes under environmental disturbances, and are evaluated in terms of the overall energy expenditure and the settling time to the desired vessel speed. It is demonstrated that the proposed approach achieves a reduction in energy consumption of up to 1.9% in a rough sea scenario.