Sizing and energy management of a medium hybrid electric boat

Abstract

Fuel consumption is viewed as a fundamental problem in boats which are to operate on sea for a long time without need to refueling. In this paper, hybridization of a conventional medium-sized boat to reduce fuel consumption is considered. For this purpose, the optimal sizes for the main components, electric motor, internal combustion engine, and battery and generator are calculated via a constrained particle swarm optimization algorithm which considers accelerating and speeding expectations as the constraints. Furthermore, a new fuzzy-thermostat controller whose parameters are tuned via optimization is proposed to manage the energy flow between the main components. To estimate the fuel consumption, a backward-forward simulation approach based on the quasi-static maps of the diesel engine and electric motor is employed. Moreover, the boat resistance forces are calculated for a typical driving cycle at both displacement and planning modes. Simulation results reveal that hybridization of the conventional boat leads to a 40 % reduction in fuel consumption without violating the performance constraints.

Recent developments in energy storage systems for marine environment

“…These design factors cause the fully installed energy density of lithium NMC battery packs to be around half of that for automotive battery packs -86 W h kg À1 for the Ellen Eferry vs. 160 W h kg À1 for a Tesla Model 3. 31,32 Because lithium NMC marine battery installations require so much compromise to be made safe, there is significant scope for using lower performance but safer chemistry to achieve similar or better overall performance. A good example is lithium iron phosphate (LFP), which has around 65% of the specific energy of NMC but is far safer and replaces expensive and problematic nickel and cobalt with highly abundant iron and phosphorous.…”

A Comprehensive Review of Modeling and Optimization Methods for Ship Energy Systems

“…It was demonstrated that the strategy could be adapted to different hydrogen hybrid vessel sizes. In [80] a PSO algorithm was implemented for the component sizing, to reduce the fuel consumption, and a fuzzy logic controller was utilized for optimally splitting the energy between the diesel generators and the batteries. The proposed fuzzy-PSO method reduced the fuel consumption up to 40%, compared to the original conventional boat.…”

Optimising design and power management in energy-efficient marine vessel power systems: a literature review

“…Studying a series hybrid of a DC grid type, Soleymani et al (2015) optimised the sizing of the machinery. A particle swarm optimisation (PSO) algorithm was used for rightsizing a combustion engine, generator, electric motor and battery pack.…”

“…Sciberras and Grech (2012) and Sciberras and Norman (2012) studied a motor yacht with parallel topology to find an optimum solution between the two conflicting objectives of fuel consumption and physical size of the system. Instead of continuous scaling of the components as done by Soleymani et al (2015), the authors used a database of discrete components for a more reallife selection of available components. Using a rule-based control strategy, the control values for the components were set based on the velocity demand, battery SOC and the operating limits of the components.…”