Research Article Sizing and Dynamic Modeling of a Power System for the MUN Explorer Autonomous Underwater Vehicle Using a Fuel Cell and Batteries Mohamed M. Albarghot , 1 M. Tariq Iqbal , 2 Kevin Pope, 1 and Luc Rolland 3 1 Department of Mechanical Engineering, Memorial University of Newfoundland, St. John’s, NL, Canada 2 Department of Electrical Engineering, Memorial University of Newfoundland, St. John’s, NL, Canada 3 Department of Automation and Controls, University of West Scotland, Scotland, UK Correspondence should be addressed to Mohamed M. Albarghot; mma216@mun.ca Received 5 January 2019; Accepted 27 February 2019; Published 16 April 2019 Academic Editor: Johan E. Hustad Copyright © 2019 Mohamed M. Albarghot et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Te combination of a fuel cell and batteries has promising potential for powering autonomous vehicles. Te MUN Explorer Autonomous Underwater Vehicle (AUV) is built to do mapping-type missions of seabeds as well as survey missions. Tese missions require a great deal of power to reach underwater depths (i.e., 3000 meters). Te MUN Explorer uses 11 rechargeable Lithium- ion (Li-ion) batteries as the main power source with a total capacity of 14.6 kWh to 17.952 kWh, and the vehicle can run for 10 hours. Te drawbacks of operating the existing power system of the MUN Explorer, which was done by the researcher at the Holyrood management facility, include mobilization costs, logistics and transport, and facility access, all of which should be taken into consideration. Recharging the batteries for at least 8 hours is also very challenging and time consuming. To overcome these challenges and run the MUN Explorer for a long time, it is essential to integrate a fuel cell into an existing power system (i.e., battery bank). Te integration of the fuel cell not only will increase the system power, but will also reduce the number of batteries needed as suggested by HOMER sofware. In this paper, an integrated fuel cell is designed to be added into the MUN Explorer AUV along with a battery bank system to increase its power system. Te system sizing is performed using HOMER sofware. Te results from HOMER sofware show that a 1-kW fuel cell and 8 Li-ion batteries can increase the power system capacity to 68 kWh. Te dynamic model is then built in MATLAB/Simulink environment to provide a better understanding of the system behavior. Te 1-kW fuel cell is connected to a DC/DC Boost Converter to increase the output voltage from 24 V to 48 V as required by the battery and DC motor. A hydrogen gas tank is also included in the model. Te advantage of installing the hydrogen and oxygen tanks beside the batteries is that it helps the buoyancy force in underwater depths. Te design of this system is based on MUN Explorer data sheets and system dynamic simulation results. 1. Introduction Te MUN Explorer AUV is an autonomous underwater vehicle used for missions such as mapping, surveillance, oceanographic data gathering, environmental monitoring, mine detecting, and coastal defence [1]. One of the challenges facing the MUN Explorer is the power system’s capacity to complete its missions. To improve the system’s energy capacity, the MUN Explorer AUV is taken as a real example to do sizing and to build a dynamic model. Te MUN AUV has a length of 5.3 m, a diameter of 0.69 m, and a dry weight of 820 kg. In water, the fooded front and back sections of the AUV make the mass around 1400 Kg, with an average speed of 1.5 m/s, graphing over 80 Km. Some components have also been integrated into the vehicle such as computers and sensors. Hydrogen production by Proton Exchange Membrane (PEM) water electrolysis is a promising method that has been successfully developed and integrated into renewable and hydrogen energy-based systems. Renewable energy sources, such as solar and wind, are desirable for hydrogen production due to random variations and signifcant current density capabilities [2]. PEM water electrolysis technology that gen- erates hydrogen primarily emits water moisture, nitrogen, and oxygen [3]. Energy storage or backup power systems are Hindawi Journal of Energy Volume 2019, Article ID 4531497, 17 pages https://doi.org/10.1155/2019/4531497