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Efforts to reduce global greenhouse gas (GHG) emissions have significant implications for the maritime sector. Reducing global emissions requires that newly built ships become more energy efficient or that all subcomponents of ship systems improve their individual or overall energy efficiency. As a result, ship electrification, which is considered to be the most viable proposed method to achieve the emissions reduction goal, will place a large burden on the ship electrical system. The projected load will lead to improvements in all aspects of the electrical system (power generation, distribution, and consumption). This paper addresses the optimization of the distribution system, or specifically the important subcomponent, the main switchboard, through previously developed improvements, starting from the definition of the switchboard parameters, through the modification of the busbar configuration area and the implementation of novel sensor technology, to ultimately optimize the design compared to an existing solution.

The laboratory facilities of the faculty play an important role in training future maritime electrical engineers. With the electrification of the marine industry, the importance of understanding electrical laboratory equipment is increasing. Technological advances will expose future maritime electrical engineers to increasingly complex systems, circuits, and topologies. In this paper, the focus is on a widely used component, the self-commutated power converter. The aim of the paper is to familiarize the students with the topology of the converter used in the laboratory exercises. The used converter is built on black-box principle i.e., the students cannot see the discrete components. The schematic that can be seen on the converter itself represents the mains filter and the dU/dt filter on blackbox principle, i.e. the manufacturer does not provide any technical details about the filters. The model of the converter with mains and dU/dt filters is created using Matlab/Simulink Simscape components. To validate the model, the voltage and current waveforms measured on the actual device using an oscilloscope and the original manufacturer's software are compared with the simulated output waveforms.

Optimization of a ship's high voltage (HV) switchboard at the individual switchgear level with the aim of improving the overall energy efficiency is achieved by reducing various influencing factors. The optimized switchgear design still has to meet the conditions regarding thermal, electrical and mechanical stress. Therefore, new designs of AirInsulated Switchgear (AIS) are subjected to various type tests to verify their compliance with the relevant standards before they can be used in an electrical system. In preparation for type testing, various computer- based simulations must be performed to predict the behaviour of the proposed design. These predictions help to keep the overall production cost to a minimum, as various problems that lead to type test failure can be identified in advance. One of the type tests to be fulfilled is the temperature rise test, where the thermal stress of the busbars at rated current is analysed, with rise limits defined according to IEC 62271-1. In this paper, the temperature rise analysis of several selected three-phase busbar systems for use in a newly proposed AIS design using FEM and CFD is presented. In order to save computational time, simplified models are used for the first selection, where the electromagnetic losses of the busbars are used as the source of heating and natural air convection is also considered. The objective of the simulation is to select a busbar configuration that has the lowest temperature rise and electromagnetic losses, which ultimately contributes to the overall energy efficiency of a ship's electrical distribution system.

The training and practice of future marine engineers in the field of marine electrical systems in realistic conditions presents several risks, especially if the training is regarding high voltage electrical systems. In order to minimize the aforementioned risks, the training should be conducted on a simulation model that can adequately simulate the behaviour of the analysed systems so that the quality of the training is not affected. In this paper, the steady-state behaviour of an induction motor fed by a two-level voltage source inverter (2L-VSI) is investigated. Lucas-Nulle devices allow the measurement and recording of a large number of values such as voltage, current, slip, power factor, active power, reactive power, power, voltage and current frequency spectrum, modulation signal. In this work, the objective is to build a simple space vector modulation signal generator using "black box" library components in Simulink and use the measurement to validate the parameters of the inverter and induction motor. The results of the Simulink model on the motor side show good agreement with the measurement result, indicating that the motor parameters are correctly determined.