## 1 Introduction
The integration of energy storage systems with lithium-ion batteries (Li-ion ESS) as backup energy sources further enhances the resilience and fault tolerance of these systems [22]. Hybrid electric propulsion systems, which combine traditional diesel generators with advanced energy storage systems such as lithium-ion batteries, offer promising solutions for reducing greenhouse gas emissions by using hardware-in-the-loop (HIL) simulations to analyze the interaction between diesel generators, battery storage systems, and propulsion components [23]. In order to achieve the best possible PMSM design, several models based on both traditional genetic algorithms and modern machine learning techniques have been proposed [24]. Utilizing the Symbiotic Organisms Search Algorithm (SOS), PMSM optimization in azimuth thruster type propulsion systems was achieved. The algorithm is judged to be an efficient solution, achieving reductions in core losses and oscillation torque of 12.5% and 60%, respectively [25]. Thus, the torque-speed profile in electric ship propulsion differs significantly from that in a typical electric vehicle. Therefore, the operation of the motor in the region of magnetic field attenuation, which is the great advantage of topologies with internally mounted magnets, is no longer necessary [26]. Another category includes superconducting motors that show particular advantages over induction motors and modern permanent magnet motors. Their main advantages are related to their high power density and torque and their overloading capabilities. They are mainly observed in military applications, as their costs are considered particularly high for conventional merchant ships [27]. One exception to this which has been used in small vessels is BLDC motors made from standard conventional materials with 3D printed technology, as presented in [28]. In addition, Vernier-type motors [29] have been investigated and tested, focusing on their optimization [30]; however, for reasons of manufacturing complexity, they are not preferred. The construction of electric motors for large volume ship propulsion systems is of great research interest. With the evolution of exhaust systems, LNG carriers have replaced steam and given rise to the creation of dual-fuel systems with electric propulsion [31]. Such systems include dual-fuel generators, which use both boil off gas (BOG) and heavy fuel oil (HFO). Propulsion engines are typically high-power induction motors of the order of 10-15 MW each, driven by variable speed drives with pulse-width modulation. Such an electric propulsion system was studied in [32]. Multiphase induction motors in marine applications show increased efficiency, reduced harmonic distortion, and minimized torque ripple. Their design requires adjustments to achieve the optimal winding arrangement [33]. In this study, the specifications that a motor should satisfy are determined. Then, through sensitivity analyses and the application of an optimization algorithm, an optimal geometry for an induction motor is obtained. In the context of ship electrification, the selection of electric propulsion systems must consider various operational constraints such as the installation space, continuous operation under varying loads, and the need for high efficiency to optimize fuel consumption. PMSMs offer distinct advantages in terms of power density and operational efficiency, while IMs remain a cost-effective and well-established alternative. Wound Rotor Induction Motors (WRIMs) offer significant advantages over Squirrel Cage Induction Motors (SCIMs) for high-power marine applications, primarily due to their ability to regulate rotor resistance via slip rings, enabling superior starting torque and controlled acceleration--critical for large vessels which need to overcome high inertia loads [34]. Unlike SCIMs, WRIMs allow for precise speed control without complex external converters, thereby enhancing adaptability to varying operational conditions [35].