This master’s thesis investigates the design, challenges, and protection mechanisms of electrical power distribution systems on ships with a particular emphasis on DC distribution systems. A key focus is on the challenges of DC systems, including protection difficulties and unique characteristics, as well as their environmental benefits and contribution to sustainability. The thesis dedicates a significant portion to the technical analysis of short-circuit currents in DC grids, offering methodologies for their calculation and protection devices like fuses and circuit breakers. Relevant standards such as IEC 61660 and IEC 60269-1 ground these discussions, ensuring their practical relevance. The thesis includes a detailed simulation model of the DC grid of a vessel, developed using MATLAB-Simulink. The simulation analyses several scenarios, including short circuits and different operational modes, by examining crucial system components such as generators, IGBTs, batteries, drives, and link capacitors. The simulations  showcase the efficacy of protective measures by examining the performance of fuses and circuit breakers in different scenarios. The simulation results of the DC grid's performance under different short circuit scenarios, with and without protective measures, provide valuable information for optimising these systems for maritime applications. The thesis concludes with an improved Simulink model incorporating enhanced battery protection, demonstrating the potential for increased safety and reliability in shipboard DC power distribution systems.