Distance relays are utilized to protect transmission lines from any fault occurrences. However, there are still many distance relays that rely solely on measurements from the local terminal (standalone) to estimate fault impedance and determine the fault zone. This impedance-based method, which solely utilizes local terminal measurements, can be influenced by numerous unknown parameters, with fault resistance having the greatest impact. During transient periods, a DC component exists in fault current, which decays after a certain time. This DC component can cause the relay to perceive the fault current as higher than its actual value, thus affecting the apparent impedance estimated by the relay. This paper provides two enhancements on the standalone distance relay for accurate apparent impedance measurement which are for DC component and fault resistance. For the DC component, Fourier Transform was employed to extract the magnitudes of the fundamental and DC components of the fault current. The magnitude of the fundamental component was then subtracted from the magnitude of the DC component and passed to the relay algorithm. The result of the DC component compensation shows that the compensated apparent impedance is more secure and avoids falsely entering the lower zone, which could lead to relay maloperation. For further enhancement by eliminating the effect of fault resistance, this paper proposes using the reactance method to estimate fault location. This fault location is then utilized to estimate the total fault resistance as seen from the local terminal, allowing for a correct estimation of total fault impedance. The results demonstrate that the proposed method accurately determines actual fault locations and estimates apparent fault impedance with an average error of less than 1%.

Grounding enhancement materials (GEMs) are one of the additive materials which can change the grounding performance without lots of significant costs. The study aimed to assess the performance of laterite and peat soil, copper and galvanized conductors, and determine the effectiveness of additional materials in reducing grounding resistance. Altering soil characteristics can enhance the conductor's contact area, achieving lower grounding resistance without high costs. Hydrogel, silica gel, and charcoal ash were mixed with soil for testing. Grounding resistance values were measured and collected using the Fall-of-Potential Method using Kyoritsu Earth-Tester-Model-4102. The number of GEMs used were 300g and 600g. Hydrogel, silica gel, and charcoal ash added to soil reduced grounding resistance. Among the various Ground Enhancement Materials (GEMs) tested, hydrogel exhibited the most impressive performance, boasting the lowest grounding resistance at just 56% compared to the reference grounding system. Silica gel followed closely as the second-best performer, with an average grounding resistance of 77% relative to the reference system and lastly is charcoal ash with an average grounding resistance of 77% relative to the reference system. These GEMs significantly enhanced soil conductivity. Furthermore, when considering different soil types and conductor materials, it was observed that peat soil combined with galvanized conductors achieved notably lower grounding resistance in comparison to laterite soil and copper conductors, respectively.

This paper proposed beam steering MIMO antenna for 5G application at 3.5 GHz of mid-band. The beam steering performance is based on the integration of the driven parasitic element and switches. The RT Duroid 5880 is used as substrate with a thickness of 1.57mm. The geometry of the center rectangular patch antenna to achieve the desired resonance frequency which 3.5GHz. The integration of the HPNP 4005 PIN Diode with the parasitic element is tested which the antenna manages to steer the direction at −30°, 0° and +30° with gain of 6.4dBi. However, the driven element achieved the gain, total efficiency, directivity, and bandwidth of microstrip antenna such as 7.106dBi, 75.88%, 8.703dBi and 100MHz. In the proposed design, a simple biasing circuit is employed to control all the PIN Diodes switches. The $2 \times 2$ MIMO is built at antenna at 3.5GHz mid-band of 5G. The proposed MMO antenna could be potential for 5G application.

In this paper, the hybrid PSOGSA, which is a combined algorithm of Particle Swarm Optimization (PSO) and Gravitational Search Algorithm (GSA), is proposed to find the optimum locations for the lightning protection system on the 81- bus radial distribution system. Moreover, the System Average Interruption Frequency Index (SAIFI) is considered as the objective function and will be minimized. The main advantage of this work is the simplicity and convenience of finding an optimal solution using the proposed PSOGSA algorithm. Additionally, PSOGSA is also capable of finding the optimal locations for applying a lightning protection system (LPS) in a distribution network, while minimizing SAIFI and maintaining computational efficiency. To validate the effectiveness of the proposed algorithm, numerical simulations are carried out considering the interdependency between lightning phenomena and the distribution feeder characteristics, namely, the flashover rates due to direct and induced lightning. In addition, a comparison between PSO, GSA, and PSOGSA is made to compare and validate the performance of the algorithms. The results show that the latter is better at escaping from local optima and has a faster convergence than the standard PSO and GSA. PSOGSA also managed to achieve a higher reduction of 12.10% SAIFI after applying LPS on the optimal feeders, as compared to the 10.79% and 11.77% reduction of SAIFI by GSA and PSO, respectively. PSOGSA also has a faster convergence speed than PSO.

Microgrids are among the promising green transition technologies that will provide enormous benefits to the seaports to manage major concerns over energy crises, environmental challenges, and economic issues. However, creating a good design for the seaport microgrid is a challenging task, considering different objectives, constraints, and uncertainties involved. To ensure the optimal operation of the system, determining the right microgrid configuration and component size at minimum cost is a vital decision at the design stage. This paper aims to design a hybrid system for a seaport microgrid with optimally sized components. The selected case study is the Port of Aalborg, Denmark. The proposed grid-connected structure consists of renewable energy sources (photovoltaic system and wind turbines), an energy storage system, and cold ironing facilities. The seaport architecture is then optimized by utilizing HOMER to meet the maximum load demand by considering important parameters such as solar global horizontal irradiance, temperature, and wind resources. Finally, the best configuration is analyzed in terms of economic feasibility, energy reliability, and environmental impacts.

Marine sector decarbonization is another important battlefield for meeting the goal of climate action and ensuring the fulfillment of ambitions for a zero-emission society. Driven immediately by the policy incentives such as Energy Efficiency Design Index (EEDI) from International Maritime Organization(IMO), carbon taxation and labeling, a series of innovations centered around marine transportation are emerging from both industry and academia. As an efficient energy system form, the microgrid is playing an increasingly important role as the system constitution form for various marine energy systems. With specific concern about multi-energy integrations, the conventional definition of the microgrid needs also to be extended for an integrated energy system. In this paper, we will first introduce the extended concept of the microgrid as an integrated energy system and its applications in the marine sector, and then present the state of the art for the control, operation, and system integration for it and its clusters. The challenges and opportunities for marine integrated energy microgrids will also be discussed to shed light on future research.

For many offshore activities, including offshore oil and gas exploration and offshore wind farm construction, it is essential to keep the position and heading of the vessel stable. The dynamic positioning system is a progressive technology, which is extensively used in shipping and other maritime structures. To maintain the vessels or platforms from displacement, its thrusters are used automatically to control and stabilize the position and heading of vessels in sea state disturbances. The theory of dynamic positioning has been studied and developed in terms of control techniques to achieve greater accuracy and reduce ship movement caused by environmental disturbance for more than 30 years. This paper reviews the control strategies and architecture of the DPS in marine vessels. In addition, it suggests possible control principles and makes a comparison between the advantages and disadvantages of existing literature. Some details for future research on DP control challenges are discussed in this paper.

Electric and Hybrid Propulsion Muzaidi Othman, Namireddy Praveen Reddy, Pramod Ghimire, Mehdi Karbalaye Zadeh, Amjad Anvari Moghaddam, Josep M. Guerrero Norwegian University of Science and Technology, Trondheim, Norway Aalborg University, Aalborg, Denmark University of Malaysia Perlis, Malaysia

Onboard hybrid power systems with low -emission energy carriers are a promising solution for green shipping replacing conventional diesel engine -based energy systems. However, there are several existing challenges related to these new low -emission energy solutions that need to be investigated. A full-scale infrastructure for testing and verification of such systems is one of the important steppi...

Trending in the maritime industry nowadays, is towards an energy efficient and fuel saving. Moreover, concerns regarding global warming issues caused by massive air pollution in sea area by the ship combustion engine and depletion of fossil fuels have attracted attention and opportunities for many parties. The electric propulsion has been used in ship for many years. It has triggered the concept of all electric ship where all electrical equipment including electric propulsion, connected to the electrical networks to achieve better fuel consumption with less emission. However, the main generation in the ship is still diesel generators. Connecting more generator in parallel is normal practice to cater the load. However, due to the nature of non-linear characteristic in thermal unit, such as diesel generator, based on specific fuel consumption (SFC) curve, the generator loading is not efficient when running the generator with low load factor or higher SFC. Thus, the effective energy scheduling is needed among the generators so that the generators is operated in optimum point. The case study in this paper is ferry, with a conversion from traditional diesel mechanical power to electric propulsion powered by diesel generator as a main source and energy storage as secondary source. This paper analyzes how much the operating cost of the scheduled system implemented in this practical electric ferry based on an estimation of SFC curve considering the dynamic load profile.

This paper presents the optimal design and specifies the dimension, energy planning and evaluates the performance of a microgrid to supply the electricity to the load by using integrated microgrid. The integrated system consists of PV, wind turbine and a battery for grid-connected. This paper also analyzes the performance of the designed system based on seaport located in Copenhagen, Denmark as a case study. The analysis is performed by using Hybrid Optimization Model for Electric Renewables (HOMER) software which includes optimization and sensitivity analysis result. The simulation result indicates that the implementation of microgrid technologies would be a convenient solution to supply the electricity to the load applied (shipboard).

Concerns about the impact of global warming caused by air pollution and depletion of fossil fuels have attracted attention and opportunities in transportation especially in maritime industry. In all electric ships, the electrical equipment including electric propulsion is connected to the common ship electrical network to achieve better fuel consumption with less emission. However, the low-load factor of the parallel diesel generators (DGs) in some operating conditions, can negatively affect the fuel consumption rate. As an alternative, two or more power sources such as batteries and renewable-based prime movers can be integrated into the system aboard to improve the overall system performance. By optimal scheduling of the power sources, poor low-load efficiency can be avoided and controllable units can be dispatched in an emission-aware and cost-effective manner. This paper analyzes how much the operating cost of a shipboard system can be improved (based on estimation of specific fuel consumption (SFC) curve of a real system) considering the dynamic load profile with and without energy storage systems (ESSs). The case study in this paper is a ferry with a conversion from traditional diesel mechanical power to electrical propulsion powered by DGs and ESSs.

Strict regulation on emissions of air pollutants imposed by the maritime authorities has led to the introduction of hybrid microgrids to the shipboard power systems (SPSs) which acts toward energy efficient ships with less pollution. A hybrid energy system can include different means of generation such as renewables (e.g., solar PV, wind power) and conventionals (e.g., diesel engines) as well as energy storage systems (ESSs) such as batteries, fuel cells and flywheels. To optimally manage different energy sources in a shipboard microgrid while meeting different technical/environmental constraints, it is necessary to set up an energy management system. This paper provides an overview of hybrid shipboard microgrids and discusses different methods of power and energy management in such systems which are essential for control, monitoring and optimizing the overall system performance in various mission profiles.

The development of electrical power systems in maritime applications like ships, ferries, vessels and seaports are calling for more advanced technologies integrating power electronics, energy storage devices, control and supervisory systems and onboard communications. The challenges of those electrical isolated systems are being solved in other terrestrial microgrid applications, so that many ideas and concepts can be shifted and adapted in order to reduce the fuel consumption in marine applications. Compared with terrestrial microgrid applications, the concept of AC and DC SMGs are presented in this paper. Several relevant technologies and standards are provided to ensure adequate power quality and fuel efficiency in ship systems. However, there are still technological challenges and de-risking studies related to the control, protection and management of the system to be performed yet.

This paper presents a three-phase switched-battery multilevel (SBM) inverter for solar photovoltaic (PV) applications. The proposed inverter requires less number of power MOSFETs and gate drivers, and therefore, it is expected to be more compact and reliable than the conventional cascaded H-bridge multilevel (CHBM) inverter. For example, sixty units of power MOSFETs are required to construct a three-phase 11-level CHBM inverter, whilst a SBM inverter with the same number of levels needs only 27 units. The switching losses of the SBM inverter are expected to be lower than that in conventional PWM-controlled inverters because the power MOSFETs in the SBM inverter are switched at a much lower frequency. In addition, the proposed inverter has an integrated charge mode operation which is very suitable for solar PV applications. The performance of an 11-level SBM inverter has been evaluated using PSIM software and the simulation results confirm that the proposed inverter is capable of producing low total harmonic distortion (THD) AC voltages without the need of bulky filters.

This paper provides a case study in solar radiation and the potential evaluation of solar energy harvesting at 6.431°N, 100.185°E, in Kangar, Perlis, Malaysia. As a state located in the Northern region, Perlis is highly potential in the development of a solar energy harvesting system. However,in order to start harvesting the solar energy as an alternative electricity utility source, it is essential to investigate the amount of solar radiation received at the location beforehand. This paper, defines the parameters of solar radiation and shows the geometrical relationship of its natural resources in order to determine the potentiality. The value of solar radiation was collected from the installed weather station and from the calculation based on the equations.