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As the world transitions to renewable electrification to reduce CO2 emissions, remote island electrification remains a challenge. Although some islands are connected to the grid, many still rely on fossil fuels for electricity generation. Several studies indicate that renewable energy sources, such as wave energy, have the potential to make these islands self-reliant because of their substantial power potential. However, research on the control of power electronics converters for these systems remains limited. This paper proposes isolated grid-forming control for island electrification to address this gap using a wave energy converter and an energy storage system. Resistive loading control is implemented to optimize the power absorption of the generator. The result illustrates the establishment of the required AC voltage and 50 Hz frequency in the island load, ensuring harmonics compliance with the recommended standards. Experiments were conducted to test and validate the operation of different converter controls. The results also demonstrate the converter's ability to black-start the island load and automatically transition the load current with varying loads in a few milliseconds. Furthermore, the power quality produced by the wave energy converter presents one of its significant challenges. Therefore, the performance of two distinct converter technologies was compared. The performance of the IGBT converter was evaluated against that of the SiC-based converter in terms of power quality. The study demonstrates that the use of SiC enhances power quality in all switching frequencies tested, achieving the most significant reduction of 78% in current THD and 92% in voltage THD at the 25 kHz switching frequency, thus validating its advantages for wave energy converter applications.

The integration of artificial intelligence into the development and production of mechatronic products offers a substantial opportunity to enhance efficiency, adaptability, and system performance. This paper examines the utilization of reinforcement learning as a control strategy, with a particular focus on its deployment in pivotal stages of the product development lifecycle, specifically between system architecture and system integration and verification. A controller based on reinforcement learning was developed and evaluated in comparison to traditional proportional-integral controllers in dynamic and fault-prone environments. The results illustrate the superior adaptability, stability, and optimization potential of the reinforcement learning approach, particularly in addressing dynamic disturbances and ensuring robust performance. The study illustrates how reinforcement learning can facilitate the transition from conceptual design to implementation by automating optimization processes, enabling interface automation, and enhancing system-level testing. Based on the aforementioned findings, this paper presents future directions for research, which include the integration of domain-specific knowledge into the reinforcement learning process and the validation of this process in real-world environments. The results underscore the potential of artificial intelligence-driven methodologies to revolutionize the design and deployment of intelligent mechatronic systems.

With more electric vehicles introduced in society, there is a need for the further implementation of charging infrastructure. Innovation in electromobility may result in new charging and discharging strategies, including concepts such as smart charging and vehicle-to-grid. This article provides an overview of vehicle charging and discharging innovations with a cable connection. A MATLAB/Simulink model is developed to show the difference between an electric vehicle with and without the vehicle-to-grid capabilities for electricity grid prices estimated for Sweden for three different electric vehicle user profiles and four different electric vehicle models. The result includes the state-of-charge values and price estimations for the different vehicles charged with or without a bidirectional power flow to and from the electric grid. The results show that there is a greater difference in state-of-charge values over the day investigated for the electric vehicles with vehicle-to-grid capabilities than for vehicles without vehicle-to-grid capabilities. The results indicate potential economic revenues from using vehicle-to-grid if there is a significant variation in electricity prices during different hours. Therefore, the vehicle owner can potentially receive money from selling electricity to the grid while also supporting the electric grid. The study provides insights into utilizing vehicle-to-grid in society and taking steps towards its implementation.

Reliable access to drinking water and electricity can be a challenge, especially on islands. In this paper, desalination systems powered stand-alone by renewable energy sources are discussed, with a focus on wave power for the Swedish island Gotland. The objective is to evaluate the opportunity of using wave power for a desalination system on Gotland. The method includes assessing the electricity generation from a wave power park to power a desalination plant. The results show that the desalination plant would require 350 MWh annually, whereas the wave power plant could deliver 1891 MWh, supporting that it is technically feasible for a wave power park installed off the coast of Gotland to power a desalination plant.

Ocean waves have the potential to contribute to future renewable electricity production. A wave energy converter (WEC) is a technology developed to absorb the energy of the wave and convert it to another form of energy. The Uppsala University WEC (UU WEC) is a point absorber with a direct drive permanent magnet synchronous linear generator power take off. Among other parameters affecting the value of absorbed power for UU WEC are the buoy size, mass of the system consisting of the buoy and translator, and available wave energy at the site of interest. This study reviews the earlier static model that considered only static forces as the buoyancy and gravity forces and neglected all dynamic forces. The static model was proposed to simplify the early-stage design decision. Although the static model was applied to two UU WECs of different dimensions, the present study shows that the static model is not held for certain buoy and translator dimensions. As an alternative, the dynamic model which accounts for the impact of hydrodynamic forces and various translator masses is proposed. The dynamic model is based on Cummins' equation and the linear potential flow theory, and the damping force is approximated as a viscous damper with the constant damping coefficient optimizing the absorbed mechanical power under a particular sea condition. The dynamic model is applied to four fixed buoy geometries of two shapes (cylinder and cylinder with a moonpool), each of two different dimensions, but the method can be extended to other buoy shapes and dimensions. In addition, the impact of translator mass was assessed for two sites located on the west coast of Sweden and near Gran Canaria, Spain. A translator of 10–11 t promotes 16.8% higher annual average power absorption for a cylindrical buoy compared to a translator of 6 t for the same buoy. However, heavier translators up to 15 t provide only 1.1% increase in average annual absorbed power.

Mechatronic product development is a complex and multidisciplinary field that encompasses various domains, including, among others, mechanical engineering, electrical engineering, control theory and software engineering. The integration of artificial intelligence technologies is revolutionizing this domain, offering opportunities to enhance design processes, optimize performance, and leverage vast amounts of knowledge. However, human expertise remains essential in contextualizing information, considering trade-offs, and ensuring ethical and societal implications are taken into account. This paper therefore explores the existing literature regarding the application of artificial intelligence as a comprehensive database, decision support system, and modeling tool in mechatronic product development. It analyzes the benefits of artificial intelligence in enabling domain linking, replacing human expert knowledge, improving prediction quality, and enhancing intelligent control systems. For this purpose, a consideration of the V-cycle takes place, a standard in mechatronic product development. Along this, an initial assessment of the AI potential is shown and important categories of AI support are formed. This is followed by an examination of the literature with regard to these aspects. As a result, the integration of artificial intelligence in mechatronic product development opens new possibilities and transforms the way innovative mechatronic systems are conceived, designed, and deployed. However, the approaches are only taking place selectively, and a holistic view of the development processes and the potential for robust and context-sensitive artificial intelligence along them is still needed.

The electrification of remote islands has long been a subject of research interest, primarily because of their historical reliance on fossil fuels, leading to a significant carbon footprint. Recent advancements in wave energy converters offer a promising avenue to make these islands more self-sustainable while considerably reducing carbon emissions. However, the persistent issue of voltage dips due to weaker grids continues to pose a challenge. This study introduces a multi-mode converter control strategy with the goal of electrifying remote islands, employing a linear generator-based wave energy converter in a unified electrical model. Various scenarios, including voltage dips and mainland grid disconnection, are simulated using MATLAB/Simulink. The study demonstrates the converter's ability to transition swiftly and smoothly in response to these scenarios, ensuring an uninterrupted power supply. Furthermore, the analysis indicates that the power quality at the point of common coupling remains well within acceptable standards.

Power electronic inverters play a crucial role in modern power systems. They are designed to have fault ride-through capabilities, allowing them to continue operating even during fault conditions. The study focuses on unsymmetrical faults that occur in the presence of inverter-interfaced distributed generators with voltage support capability, which involves the compensation of positive and negative voltage sequences during faults to maintain voltage stability. Different fault scenarios are simulated in MATLAB/Simulink using a detailed model of the distribution system, including the inverter-interfaced distributed generators and their control strategies. The results demonstrate that inverter-interfaced distributed generators with local voltage support can improve the system’s fault ride-through capability by reducing voltage drops and unbalances. Overall, this research contributes to a better understanding of fault behavior in power distribution systems with inverter-interfaced distributed generator voltage support.

The modelling of a three-phase four-leg four-wire grid-forming inverter in a low voltage distribution system 18-bus European Cigre under unbalanced conditions in an autonomous distribution network is presented. The case study has two types of inverters control strategy: (i) grid-forming to supply all the system demand in the interval of the intentional supply interruption and (ii) grid-following to integrate photovoltaic renewable energy resources into power systems. The model suggests a control scheme with two loops: An inner current loop with a proportional-integral controller and an outer voltage loop with a proportional controller, both in the synchronous reference frame (dq0), in which dq-axis are decomposed in positive and negative sequences. Simulation results, carried out using the PSCAD software, showed the effectiveness of the suggested control strategy with smooth synchronization where the grid-forming inverter was able to form a network with an unbalanced degree lower than 2%, sinusoidal voltage and frequency within standard limits 49.5-50.5 Hz.

With more electric vehicles introduced in society, there is a need for further implementation of charging infrastructure. Innovation in electromobility may result in new charging and discharging strategies, including novel concepts such as smart charging, vehicle-to-grid and vehicle-to-everything. Access to charging infrastructure and novel ideas on charging or discharging may contribute to driving the transition towards e-mobility. This article aims to provide an overview of vehicle charging and discharging innovations with a cable connection, including an example of a MATLAB/Simulink model of vehicle-to-grid dynamics.