This paper presents a comparative analysis of control methods to achieve an optimal PV module output voltage and to track the maximum power point from photovoltaic PV systems under changeable conditions such as (Temperature and solar irradiances) and load changes, with the help of Perturb and Observe “P&O ” algorithm that provides the reference voltage. The PV system consists of a solar module and a DC/DC converter; in this case a boost converter is used, connected to a load. The first is to use the integral and derivative (PI) controller, while in the second a Backstepping, with and without integral action, is used. The study is done for a centrifugal pump driven by permanent magnet DC motor. The parameters considered for the comparison are the extracted power from the PV system under changeable conditions such as the temperature and the irradiances and signal ripples. Simulations used to demonstrate the efficiency of the compared methods in presence of the environmental perturbations and load changes.

This paper presents a practical and communication-independent energy management system (EMS) for a DC microgrid supply within the firezone of a cruise ship. The proposed approach prioritizes operational reliability and fault tolerance under emergency conditions, where communication availability and control complexity should be minimized. The proposed DC microgrid integrates photovoltaic systems (PVs), fuel cell systems (FCs), and lithium-iron-phosphate (LFP) battery energy storage systems (BESSs), coordinated through a rule-based EMS combined with droop-controlled converters. The electrical topology considered in this study is a collaborative development of the project consortium of the publicly funded project Sustainable DC Systems (SuSy), featuring a novel configuration with two independent horizontal busbars for the Cabin Area Distribution (CAD) and Technical Area Distribution (TAD). The EMS can manage two operational scenarios: (i) regular operation, with two decentralized droop controls where power generation is distributed among all generators based on their respective capacities, and a power curtailment strategy is applied to prevent overcharging of BESSs; and (ii) irregular operation, where a fault on one of the vertical busbars triggers the use of reserved battery storage capacity on both sides of the ship and activates load-shedding to ensure continued operation of critical loads and sustain grid functionality. The effectiveness of the proposed architecture is validated through detailed MATLAB/Simulink simulations. Under regular conditions, the EMS achieves stable voltage regulation, balanced power sharing, and efficient energy curtailment. During fault conditions, the battery storage on both sides successfully supports the critical loads. The fuel cells are operated in power-controlled mode effectively up to their full rated 6$\mathrm{k}$$\mathrm{W}$ capacity while the DC bus voltage stabilization is ensured by the battery energy storage systems. These results validate the proposed EMS as a robust and low-complexity solution for maritime DC microgrids, offering stable voltage regulation, effective load prioritization, and resilient operation of critical loads.