Electrical Energy Research Articles

Smart grid deployment: from a bibliometric analysis to a survey

Smart grids are one of the last decades' innovations in electrical energy. They bring relevant advantages compared to the traditional grid and significant interest from the research community. Assessing the field's evolution is essential to propose guidelines for facing new and future smart grid challenges. In addition, knowing the main technologies involved in the deployment of smart grids (SGs) is important to highlight possible shortcomings that can be mitigated by developing new tools. This paper contributes to the research trends mentioned above by focusing on two objectives. First, a bibliometric analysis is presented to give an overview of the current research level about smart grid deployment. Second, a survey of the main technological approaches used for smart grid implementation and their contributions are highlighted. To that effect, we searched the Web of Science (WoS), and the Scopus databases. We obtained 5,663 documents from WoS and 7,215 from Scopus on smart grid implementation or deployment. With the extraction limitation in the Scopus database, 5,872 of the 7,215 documents were extracted using a multi-step process. These two datasets have been analyzed using a bibliometric tool called bibliometrix. The main outputs are presented with some recommendations for future research.

Experimental investigation of a hybrid photovoltaic-thermal energy system for hot air production

Solar energy as a non-fossil alternative energy source has become the best choice to overcome the problem of energy demand in most countries in the world. There are two different techniques to convert solar energy: photovoltaic (PV) panels to produce electricity and thermal collectors to generate heat. The two technologies can be combined to provide electrical and thermal energy either simultaneously or separately. In order to optimize the performance of a hybrid photovoltaic-thermal (PVT) solar air heater, it is necessary to collect experimental data on solar irradiation and temperature. This paper emphasized the development of a PVT energy system for hot air production in a temperature range of 50-55 °C. Additionally, experiments were constructed to monitor the information acquired from the proposed PVT solar air heater and the environment, such as hot air temperature, ambient temperature, and solar irradiation. The real-time monitoring system was set for five sample days. A microcontroller unit was used to control the hot air temperature and save the measurement data into memory. The experimental results showed that the proposed PVT solar air heater is capable of maintaining a certain level of hot air temperature throughout the day and night.

Investigations of high-Performance Ultrasonic Transducers based on PMN-PT Single Crystals

Ultrasonic transducers for NDE applications are commonly based on Lead Zirconate Titanate or PZT, an inorganic compound and ceramic perovskite material. Until now the advantages of PMN-PT are used in medical applications, but are not implemented in NDE. Lead Magnesium Niobate-Lead Titanate (PMN-PT) is well known for its high sensitivity and broad frequency spectrum. While conventional PZT materials have an electromechanical coupling factor K33 (a measure of the conversion between electrical and acoustic energy) of about 0.72, PMN-PT materials reach peak values of more than 0.93. For applications with low signal amplitudes, high electronic noise and small transducer elements, the performance of ultrasonic probes can be significantly enhanced by using Lead Magnesium Niobate-Lead Titanate (PMN-PT) instead of PZT. This single-crystal material offers significantly better piezo parameters and leads to a higher sensitivity and larger bandwidth. There is a better depth resolution possible with this transducers as practical tests have shown. Similar to PZT it can also be fabricated in 1-3 piezo- composite technology. In a cooperation between Fraunhofer IKTS, iBULe Photonics, and IFU Diagnostic Systems, PMN-PT ultrasonic transducers are developed and optimized. The performance of phased array probes and single element transducers was measured by a so called PCUS® pro electronic front end from Fraunhofer and compared with equivalent PZT-based probes. As a result various single element and phased array transducers with im-proved performances are available for NDT of typical aerospace materials and applications. These test setups were used to weigh up the advantages and disadvantages, such as achievable precision or costs, for the implementation of a PMN-PT-based UT matrix probe. Based on this, a wiring variant adapted to the PMN-PT was developed and optimised for the matrix setups by pre- assembling the matching layers. The most favourable setup turned out to be bonding the PMN- PT composites to the prefabricated matching layers together with a rigid-flexible PCB frame. This enabled direct wire bonding of 64 matrix elements to the matching PCB pads on the rigid frame.

Enhancing battery system identification: nonlinear autoregressive modeling for Li-ion batteries

Precisely characterizing Li-ion batteries is essential for optimizing their performance, enhancing safety, and prolonging their lifespan across various applications, such as electric vehicles and renewable energy systems. This article introduces an innovative nonlinear methodology for system identification of a Li-ion battery, employing a nonlinear autoregressive with exogenous inputs (NARX) model. The proposed approach integrates the benefits of nonlinear modeling with the adaptability of the NARX structure, facilitating a more comprehensive representation of the intricate electrochemical processes within the battery. Experimental data collected from a Li-ion battery operating under diverse scenarios are employed to validate the effectiveness of the proposed methodology. The identified NARX model exhibits superior accuracy in predicting the battery's behavior compared to traditional linear models. This study underscores the importance of accounting for nonlinearities in battery modeling, providing insights into the intricate relationships between state-of-charge, voltage, and current under dynamic conditions.

The implementation of an optimized neural network in a hybrid system for energy management

In the face of increasing global energy demand and volatile energy prices, many countries are searching for solutions to ensure their energy independence. One of the most popular solutions is to incorporate renewable energy sources in their energy systems. While there are many advantages to integrating renewable energy sources, it is important to note that their intermittent operation can present challenges. Energy storage and smart grid management systems are key solutions to overcome these challenges and ensure sustainable, reliable use of renewable energy sources. In this article, we present an intelligent electrical energy management system for hybrid energy systems. This management system is based on a multi-layer neural network that has undergone an architecture optimization phase to improve the accuracy of real-time energy management and simplify its implementation. The management model that was built demonstrated highly good performance across a range of test circumstances.

Improving the protection system in the distribution networks integrated with photovoltaic cells by changing the ratio of X/R

Due to the increased demand for electrical energy, many countries were prompted nowadays to search for new sources. One important source is the photovoltaic energy. However, despite the great benefits of this source, some defects where observed when linking to distribution networks (negative impact on the protection system). Hence, an approach of improving the protection system in distribution networks integrated with photovoltaic cells is presented in this paper. The protection system improvement is proposed by changing the impedance to resistance ratio (X/R) values of the networks cables, which leads to increasing the overcurrent relays' response speed when a fault occurs. A comparative analysis with different cable reactance values was conducted. The electrical transient analyzer program (ETAP) software was used to investigate and validate the effects on the relay’s response times. Amriya Fallujah power station, located in Iraq, was investigated as a case study. Simulation results show that it is possible to increase the response speed of the overcurrent relay by reducing X/R of the network cables. For more validation, the distance relay was used to compare the best improvement results of changing the X/R ratio with the results of changing the type of relay, which also shows the strength of the proposed method.

A Multi-Stage Framework for Coordinated Scheduling of Networked Microgrids in Active Distribution Systems Considering Economic and Environmental Impact of Hydrogen Refueling and Charging Stations

Due to the increase in electric energy consumption and the significant growth in the number of electric vehicles (EV) at the level of the distribution network, new networks have started using new fuels such as hydrogen to improve environmental indicators and at the same time better efficiency from the excess capacity of renewable resources. In this article, the services that can be provided by hydrogen refueling stations and charging electric vehicles in the optimal performance of microgrids have been investigated. The model proposed in this paper includes a two-stage stochastic framework for scheduling resources in microgrids, especially hydrogen refueling stations and electric vehicle charging. In this model, two main goals of cost minimization and greenhouse gas emissions are considered. In the proposed framework and in the first stage, the service range of microgrids is determined precisely according to the electrical limitations of distribution systems in emergency situations. Then, in the second stage, the problem of energy management in each microgrid will be solved centrally. In this situation, various indicators including the output energy of renewable sources, smart charging of hydrogen and electric vehicle charging stations (EV/FCV) and flexible loads (FL) are evaluated. The final mathematical model is implemented as a multivariate integer multiple linear problem (MILP) using the GUROBI solver in GAMS software. The simulation results on the modified IEEE 118-Bus network show the positive effect of the presence of flexible loads and smart charging strategies by charging stations. Also, the numerical derivation shows that the operating costs of the entire system can be reduced by 4.77% and the use of smart charging strategies can reduce greenhouse gas emissions by 49.13%.

Techno-economic study of a hybrid photovoltaic-diesel system for a remote area in southwest Algeria

Exploiting natural sun and wind resources in remote and isolated areas is undoubtedly an excellent decision to generate electrical energy due to their availability and cleanliness. Various systems were used to generate this energy, such as photovoltaics (PV), wind turbine sand other energy systems. Moreover, for optimum energy use, some of these systems are combined either with each other or with other conventional systems, such as diesel generators with PV systems (i.e., hybrid systems). This work aims to present a technical-economic study of PV/diesel autonomous hybrid systems to supply electrical power for an isolated house located in a hot desert climate, Adrar. For optimizing the hybrid systems, hourly input data of solar radiation and load were used according to two configurations, where the annual load is 11.2 kWh/day. The findings showed that the diesel system had a high cost, with a cost for energy of $0.407/kWh and a fuel price of $0.140/l. Among the hybrid power systems but with significant pollution, the proposed hybrid system 2 kw photovoltaic and diesel generator with 2.3 kW has important economic feasibility, where the energy cost amounted to $0.172/kWh. In addition, CO2 emissions are reduced by approximately 5 tons every year compared to an independent diesel generator system.

Comprehensive evaluation of a novel pilot-scale UVA-LED photoreactor for water treatment applications: Characterization, catalytic efficiency, energy performance and economic viability

A comprehensive assessment was conducted on a novel pilot plant employing a tubular photo-reactor configuration integrated with UVA-LED technology for advanced municipal wastewater treatment applications. The plant consists of eight UVA-LED strips (150 LEDs/strip, 348–400 nm with peak emission at 370 nm) achieving a maximum irradiance of 28.1 W/m2 at 100 % power of the LED, symmetrically distributed across two borosilicate tubes. The iron concentration (0.025–0.100 mM) and UVA-LED irradiance (1.4–28.1 W/m2) combined effect on the photo-Fenton process efficiency was thoroughly examined in synthetic tap water and synthetic municipal wastewater treatment plant (MWWTP) secondary effluent using sulfamethoxazole as model microcontaminant. In general, an LED intensity threshold from which process efficiency reaches a plateau maximum value was found. The determination of the electrical energy per order (EEO) showed higher energy efficiencies as LED intensity decreases, iron concentration increases, and the water matrix is simpler. The lowest EEO obtained was 0.009 kWh/m3·order for 0.10 mM iron concentration in synthetic MWWTP secondary effluent at 5 % LED intensity. The economic study revealed that the weight of operating costs is more significant than the weight of investment costs, regardless of the selected operating conditions. Working with an iron concentration of 0.10 mM helps reduce the total costs, while operating either under excess LED intensity or insufficient LED intensity negatively impacts the total treatment cost. The lowest treatment cost (0.19 €/m3) was obtained with 0.10 mM iron concentration at only 10 % LED intensity. A comparison with the same process driven by natural solar radiation in a raceway pond reactor demonstrated the feasibility of the novel photo-reactor design in terms of treatment cost.

Advanced control scheme of doubly fed induction generator for wind turbine using second sliding mode control

This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator(DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC).Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.

Tổng hợp vật liệu LiNi0,9Mn0,05Co0,05O2 bằng phương pháp phản ứng pha rắn (NMC9.5.5-PR) ứng dụng chế tạo pin ion liti

Nickel-manganese-cobalt (NMC) transition metal oxide-based layered structural materials are evaluated a promising material for applications as cathode in lithium-ion batteries. In this study, we have successfully synthesized nickel-rich NMC material LiNi0.9Mn0.05Co0.05O2 by solid-state reaction method (NMC9.5.5- PR). The CR2032-type lithium-ion battery is also successfully fabricated from NMC material to serve the study of electrochemical properties. The NMC9.5.5-PR material exhibits outstanding discharge specific capacity when providing a maximum specific capacity of up to 212.4 mAh/g at a current density of 10 mA/g. However, the cycle efficiency survey results show that the NMC9.5.5-PR material has some disadvantages (only maintaining 81.6% of the discharge specific capacity after 50 continuous charge-discharge cycles at current density of 10 mA/g). These electrochemical properties indicate that it is necessary to further improve the cyclic efficiency of NMC9.5.5-PR material but preserving its outstanding electrical energy storage capacity. Successfully accomplishing this goal, we believe that NMC-9.5.5-PR or a material based on NMC9.5.5-PR will be one of the suitable materials to fabricate positive electrodes used in lithium-ion batteries.

Particle swarm optimization based sliding mode control for maximum power point tracking in solar PV systems

One of the most significant renewable energies is photovoltaic (PV) energy, however it has a low efficiency due to its variable maximum power point that depends on weather conditions. In order to guarantee the system's best performance, intelligent algorithms can effectively track this point in real-time utilizing the maximum power point tracking (MPPT) method. Consequently, it is crucial to maximize the use of the solar energy that has been captured as well as the PV system's generated electricity. Variations in solar irradiance affects the amount of electric energy obtained from solar arrays. For efficient extraction of electricity from solar PV systems, MPPT algorithms are required. Sliding mode control (SMC) can be used in the control of nonlinear systems. However, the effectiveness of SMC can be improved by the choice of the sliding coefficients. In this paper, optimal search using particle swarm optimization (PSO) is used in the design of the sliding manifold. Results obtained via simulations showed that MPPT tracking efficiencies obtained for the PSO based SMC and the conventional SMC are 99.65% and 96.79% respectively. That means, PSO based SMC is 2.86% better than conventional SMC.

ANALISA SISTEM ELEKTRONIK POWER STEERING UNTUK PENGEMBANGAN KENDARAAN LISTRIK FAKULTAS TEKNIK UNRAM

Recenly conventional vehicles use fossil fuels, however these fuels are non-renewable energy sources and their availability in nature is very limited. If they are explored continuously then one day they will run out, so it is very necessary to save and innovate to use these sources. Other renewable energy sources, one of which is electrical energy, where this electrical energy can be generated from various sources such as water, solar, biomass and so on. Besides that, the use of electrical energy for vehicles is currently very relevant because it is environmentally friendly, that is, it does not produce CO or CO2 gas like conventional vehicles, so this energy is known as green energy. Indonesia has the potential to produce electric cars because the availability of nickel is very abundant to be processed into batteries, as a provider or energy storage for electric cars, our country has a very big opportunity to produce electric cars. To make this happen, it is deemed necessary to carry out comprehensive studies such as power steering so that comfort and safety can be achieved. The most suitable power steering is the electric power steering (EPS) type because the energy required comes from the battery. The method applied in this research is an experimental method, by measuring torque requirements on various roads, the roads chosen are asphalt roads, block paving roads and dirt roads. Based on this data, an EPS test bench then created which was able to measure the input and output torque of the EPS and look for the power consumed by the system. Road conditions can cause differences in torque requirements, in block paving road conditions the greatest torque requirement is 2.77 Nm and the smallest occurs in asphalt road conditions at 1.62 Nm. EPS testing shows that it is only loaded up to 25% with an input torque of 1,652 Nm resulting an output torque of 3,924 Nm with an electrical power consumption of 6,31 watts.

PENGARUH VARIASI TINGGI SUDU TURBIN DARI TINGGI BASIN TERHADAP DAYA DAN EFISIENSI TURBIN VORTEX

Electrical energy is a very important need for human life in various aspects, both on a large and small scale. One of the efforts to reduce the use of fossil fuels is to use natural resources that are not limited and can be renewed. Micro Hydro Power Plant (MHP) is an alternative source of electricity for the community, one of which is a vortex turbine. The vortex turbine is one type of micro hydro turbine that utilizes a whirlpool as a blade drive. This study examines the effect of blade height variations of 25%, 30%, and 35% of the basin height on power and efficiency. The results showed that the largest turbine power at 25% blade height variation from the basin height with a discharge of 0.009 m3/s was 3.294 Watt with an efficiency of 51.10%. The largest turbine power at an angle variation of 30% of the basin height with a discharge of 0.009 m3/s is 3.364 Watt with an efficiency of 50.66%. The largest turbine power at an angle variation of 35% of the basin height with a discharge of 0.009 m3/s is 4.062 Watt with an efficiency of 62.35%. Turbine power based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine power produced and turbine efficiency based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine efficiency produced.

Smart Car Parking System and Generation of Piezoelectric Energy

Abstract: In the past few years, parking has become a costly commodity in virtually every major urban region on the earth, and scarcity is a contributing factor to traffic jam and air pollution in urban areas. The most popular method to obtain a parking place is to do it manually, in which the drivers looks for a parking area either through experience or by luck. This method takes time and effort, and it may result in the worst-possible situation of not finding a parking place if vehicle is in a place with a high vehicle density. An effort is made here to park the vehicle as well as to find a parking space for the vehicle with a framework of Smart Parking System(SPS) which is based on the law of conservation of energy in we basically convert the elements from mechanical energy into electrical energy. This document Allow user to Automatically find a free site for parking at low cost without wasting much fuel and time.

Energy Harvesting System

Abstract: This paper presents a novel energy harvesting system designed to harness ambient mechanical energy using piezoelectric sensors, with the Arduino Uno microcontroller serving as the central processing unit. The system's primary objective is to convert mechanical vibrations into electrical energy, storing it for potential use in powering low-energy electronic devices. The proposed setup incorporates piezoelectric materials strategically positioned to capture mechanical vibrations from various sources. The core of the system is an Arduino Uno microcontroller, programmed to efficiently manage the energy harvesting process. The harvested energy is stored in a rechargeable battery, ensuring a consistent power supply for applications with intermittent energy demands. To validate the effectiveness of the system, a light bulb is employed as a demonstrative load, allowing for real-time observation of the energy harvesting capabilities. The paper details the experimental setup, including the placement and configuration of piezoelectric sensors, the Arduino Uno programming logic, and the integration of a light bulb for visual confirmation of the generated current. Performance metrics such as voltage output, current production, and power generation efficiency are thoroughly analyzed under varying environmental conditions and mechanical vibrations. Results demonstrate the feasibility of the proposed energy harvesting system, showcasing its potential as a sustainable power source for low-power electronic devices. The combination of piezoelectric materials, Arduino Uno control, and a practical load application illustrates a promising approach to energy harvesting, paving the way for advancements in self-sufficient and ecofriendly power solutions

Design and Implement a BTMS using Phase Change Material - A Review

Abstract: This paper presents a comprehensive review of the design and implementation of Battery Thermal Management Systems (BTMS) utilizing Phase Change Materials (PCM). The thermal management of batteries is crucial for ensuring optimal performance, safety, and longevity, particularly in electric vehicles and renewable energy storage applications. Phase change materials offer unique advantages for thermal management, including high latent heat storage capacity, thermal conductivity, and temperature regulation capabilities. This review discusses the fundamentals of PCM-based BTMS design, including PCM selection, integration methods, and system optimization techniques. Additionally, recent advancements, challenges, and future directions in PCM-based BTMS are explored, providing valuable insights for researchers, engineers, and industry practitioners in the field of energy storage systems.

Self-Powered Hybrid Motion and Health Sensing System Based on Triboelectric Nanogenerators.

Triboelectric nanogenerator (TENG) represents an effective approach for the conversion of mechanical energy into electrical energy and has been explored to combine multiple technologies in past years. Self-powered sensors are not only free from the constraints of mechanical energy in the environment but also capable of efficiently harvesting ambient energy to sustain continuous operation. In this review, the remarkable development of TENG-based human body sensing achieved in recent years is presented, with a specific focus on human health sensing solutions, such as body motion and physiological signal detection. The movements originating from different parts of the body, such as body, touch, sound, and eyes, are systematically classified, and a thorough review of sensor structures and materials is conducted. Physiological signal sensors are categorized into non-implantable and implantable biomedical sensors for discussion. Suggestions for future applications of TENG-based biomedical sensors are also indicated, highlighting the associated challenges.

Lignocellulosic Residues from Fruit Trees: Availability, Characterization, and Energetic Potential Valorization

Reducing the carbon footprint of energy production is one of the most pressing challenges facing humanity today. Lignocellulosic biomass residues from fruit production industries show promise as a viable energy source. This paper presents a study of the Italian context concerning the utilization of orchard lignocellulosic residues for energy production as electricity or bioethanol. The potential of various orchard residues was assessed through chemical and physical analyses, and an equivalent electrical energy of about 6441.62 GWh or an amount of 0.48 Mt/y of bioethanol was obtained based on the average annual dry residue mass availability of about 3.04 Mt/y. These data represent 9.30% of the national electrical energy production from renewable sources, as well as 6.21% of the Italian demand for gasoline in 2022. Electricity generation from these residues has shown its potential as a reliable and sustainable baseload power source, as well as a source of renewable transportation fuel. The studied process could be a valuable reference to expand these concepts on a global scale to achieve a greener and more sustainable energy future.

Performance Evaluation and Thermal Stabilization of Photovoltaic Panels Using Phase-Change Materials

Photovoltaic (PV) is a widely used technology that generates power from solar energy. The solar radiations reaching PV panels are converted into electrical energy and heat, however the panel temperature increases, leading to a decrease in performance. This issue can be resolved using cooling methods. Phase-change materials (PCMs) are utilized in passive cooling methods, which do not consume energy, store the heat from the panel and cool them. In this study, sodium acetate trihydrate (PCM-1), palmitic acid (PCM-2), and an eutectic mixture of stearic acid and palmitic acid (PCM-3) were placed in a container and integrated into monocrystalline and polycrystalline PV panels to examine the impact of PCM on various performance metrics including power output, energy efficiency, and PV panel surface temperature. The experiments are carried out in Izmir, which has a hot climate condition in summer months. The solar irradiance of Izmir city and standard test condition of 1000 W/m2 were applied to the panels in the experiments. Results showed that the maximum temperature decreased, compared to the reference panel (without PCM), by 22.84% and 14.4%, respectively, when using PCM-1 and eutectic mixture in the monocrystal panel at 1000 W/m2 in August. The power and efficiency increased by 24.97% and 24.95%, respectively, for the polycrystalline panel in July. These results indicate that PCMs enhanced the cooling and increased the performance of the PV panels with high surface temperatures due to intense solar irradiation.