Electrical Energy Transfer Research Articles

Enhancing Electrical Generator Efficiency through Advanced Technologies Flotation Magnets, Sealed Vacuums, and Liquid Hydrogen Cooling.

In the scientific endeavour to enhance the efficiency of modern electrical generators, three innovative technologies: flotation magnets, sealed vacuums, and liquid hydrogen-cooled electrical energy transfer wires offer electrical engineers promising solutions to the classical problems of entropic energy loss. These three technologies aim to reduce friction at moving components points of contact, reduce or negate air resistance to moving turbines, and achieve a state of near-zero electrical resistance in the wires which transfer this energy to storage devices. This paper explores how potentially these advanced electrical engineering techniques can be integrated into the current design and operation of electrical turbine generators, with the scope of potentially revolutionising their output performance and entropic energy efficiency.

Design of Resonant Converter of Trans cutaneous Energy Transfer System to Power Artificial Heart

Wireless technologies have matured to recharge the batteries of consumer devices efficiently. The benefit of the technology is being used by mobile communication devices, personal computation devices, and wearable entertainment devices. The wireless energy transfer techniques employ the transfer of electrical energy between two-tesla coils in surface contact and not by electrical contact through the phenomenon of electromagnetic induction. Many international consortiums have made guidelines for designing and manufacturing these devices. However, for active implantable medical devices such as artificial hearts, a large amount of electrical energy usually in the range of 15W to 30W needs to be transferred across the skin at a depth of 10mm to 30mm. The design needs to be optimized for maximum power transfer with the highest possible efficiency. Any loss in power will be reflected as heat energy and cause burns and tissue death. A transcutaneous energy transfer system is such type of wireless energy transfer mechanism across the skin to power implanted life-saving devices. In this paper, the design of a resonant converter and its performance is investigated to wirelessly transfer electrical power up to a tissue thickness of about 25mm.

The "energy gap law" for mid-infrared nanocrystals.

Colloidal quantum dots are of increasing interest for mid-infrared detection and emission, but device performances will vastly benefit from reducing the non-radiative recombination. Empirically, the photoluminescence quantum yield decreases exponentially toward the mid-infrared, which appears similar to the energy gap law known for molecular fluorescence in the near-infrared. For molecules, the mechanism is electron-vibration coupling and fast internal vibrational relaxation. Here, we explore the possible mechanisms for inorganic quantum dots. The primary mechanism is assigned to an electric dipole near-field energy transfer from the quantum dot electronic transitions to the infrared absorption of surface organic ligands and then to the multiphonon absorption of the quantum dot inorganic core or the surrounding inorganic matrix. In order to obtain luminescent quantum dots in the 3-10μm range, we motivate the importance of using inorganic matrices, which have a higher infrared transparency compared to organic materials. At longer wavelengths, inter-quantum dot energy transfer is noted to be much faster than radiative relaxation, indicating that bright mid-infrared colloidal quantum dot films might then benefit from dilution.

Reviewing the effect of aggregates in Rhodamine 6G aqueous solution on fluorescence quantum efficiency

Rhodamines constitute a class of dyes extensively investigated and applied in various contexts, primarily attributed to their high luminescence quantum yield. This study delves into the impact of aggregation on the thermal and optical properties of Rhodamine 6G (R-6G) solutions in distilled water. Examined properties encompass thermal diffusivity (D), temperature coefficient of the refractive index (dn/dT), fluorescence quantum efficiency (η), and energy transfer (ET). These parameters were assessed through thermal lens (TL) and conventional absorption and emission spectroscopic techniques. The dimerization of R-6G solutions was revisited, revealing that an increase in R-6G concentration alters the features of absorption and emission spectra due to dimer formation, resulting in unexpected behavior of η. Consequently, we introduce a novel model for the fraction of absorbed energy converted into heat (φ), which accounts for emissions from both monomers and dimers. Employing this model, we investigate and discuss the concentration-dependent behaviors of η for monomers (ηm) and dimers (ηd). Notably, our findings demonstrate that ηm values necessitate ηd = 0.2, a relatively substantial value that cannot be disregarded. Additionally, applying the Förster theory for dipole–dipole electric ET, we calculate microparameters for ET between monomers (CDD) and monomer–dimer (CDA). Critical ranges for ET in each case are quantified. Microparameter analysis indicates that ET between monomer–monomer and monomer–dimer species of R-6G dissolved in distilled water holds significance, particularly in determining ηm. These results bear significance, especially in scenarios involving high dye concentrations. While applicable to R-6G in water, similar assessments in other media featuring aggregates are encouraged.

Implementing generative adversarial networks for increasing performance of transmission fault classification

<p>An electrical power system is a network that facilitates the sourcing, transfer, and distribution of electrical energy. In the traditional power system, there are eleven types of faults that can occur in the system. This paper focuses on the classification of these faults over a stretch of 100 kilometres. The dataset used is synthetic and generated from a simulated model using MATLAB/Simulink software. Data augmentation is carried out during training to improve the accuracy of the classification. An indirect training approach through generative adversarial network (GAN) is used to classify these overhead transmission line faults. The random forest (RF) classification is used as the base learning model on the original dataset and it achieves accuracy of 84%. However, the base learner RF when used on GAN model generated augmented faulty data, it performs exceptionally well achieving 99% accuracy. One of the recent state-of-art methods is compared with this approach.</p>

Design of an Enhanced Dynamic Regulation Controller Considering the State of Charge of Battery Energy Storage Systems

In recent years, the escalating electricity demand in Taiwan has heightened the prominence and discourse surrounding the issue of power supply. With the enactment of the European climate law, global commitment to achieving net-zero emissions has gained momentum. Concurrently, the Taiwanese government has articulated the Taiwan 2050 net-zero emissions policy. To realize this objective, Taiwan has vigorously promoted renewable energy in recent years, increasing the proportion of renewable energy in its energy mix. However, confronted with the intermittent and unpredictable nature of renewable energy generation, challenges arise concerning the stability and quality of power supply. In response to the impact of integrating renewable energy into the grid, the Taiwan Power Company (Taipower) has introduced the day-ahead ancillary service market. Through this platform, power generation and battery energy storage systems (BESSs) engage in competitive bidding, fostering the integration of diverse distributed energy resources into the system. These resources serve as dispatchable assets for Taipower, contributing to grid stability by providing ancillary services. This study has developed an advanced dynamic regulation reserve controller by employing an industrial PC (IPC) in conjunction with a multifunctional power meter. Through real-time measurement of the power grid frequency by the multifunctional power meter, a sophisticated dynamic frequency reserve control strategy has been devised, taking into account the charging state of energy storage systems. This strategy exhibits high operational quality, effectively regulating the charging and discharging of energy storage systems. In addition to swiftly adjusting the current grid frequency, it encompasses the capability to facilitate the transfer of peak electrical energy. This effectively stabilizes the power grid, alleviating supply pressures during nighttime peaks and enhancing the overall supply stability of the power system.

Enhancing Wireless Power Transmission Efficiency via Resonant Coupling into Coil and Wire Parameters

The concept of wireless power transmission involves the transfer of electrical energy from a power source to an electrical load without wires. The technology has become widely used in various mobile, industrial, and medical fields. This innovation eliminates the need for wires and batteries, making it a convenient and safe option for all users. Inductive and resonant coupling are the most commonly used methods for wireless power transmission. This work delves into designing and developing wireless power transmission hardware. A wireless power system comprises a transmitter (primary coil) and a receiver (secondary coil). The primary coil produces a magnetic field by passing alternating current through it. The secondary coil is then positioned close to the primary coil. When the two devices make contact, the primary and secondary coils become magnetically linked, causing the power to transfer from transmitter to receiver. To optimize the wireless power transmission using a resonant coupling, the paper tests and analyzes how different wire diameters, coil diameters, and the number of coils affect the output power.

Integration of mobile power-hydrogen storage systems in distribution-level networks: A fuzzy information gap optimization framework

In recent years, renewable energy sources (RESs) have had unquestionably significant benefits. However, maximum penetration of RESs has always been challenging due to their intermittent nature. To address this challenge, this study advances a framework for the flexibility of the distribution network (DN) by employing transportable electrical storages (TESs) and transportable hydrogen storages (THSs). To do so, the TESs are considered to transfer electrical energy among high-penetrated and high-demand points. In addition, curtailed renewable power can be converted to green hydrogen and transferred to hydrogen refueling stations (HRSs) using the THSs. To further flexibility, this work considers an incentive-based demand response (DR) program and vehicle-to-parking lot (V2PL) capable plug-in electric vehicles (PEVs). Moreover, a binary-based method is developed to carry out the trajectory planning of the TESs and THSs and the Floyd algorithm is exploited to minimize traveling and simulation time. Furthermore, the fuzzy information gap decision theory (IGDT) is proposed to enhance the scheduling robustness against the uncertainty of RESs. The obtained results corroborated the positive impact of the TESs and THSs by declining the operation cost by about 4.8 %. Moreover, the proposed uncertainty management model is quite robust against RESs’ uncertainty by achieving about 37.5 % less operation cost.

Formation of plasma channel under high-voltage electric pulse and simulation of rock-breaking process

In the context of rock fragmentation, the application of high voltage electric pulses results in the transfer of electrical energy onto the surface of the rock material, leading to a rapid electrical breakdown and the formation of a plasma channel. The ionized plasma expands at a fast velocity, generating a shock wave that causes significant damage to the rock’s integrity. In this study, we develope a numerical model that couples electrical, thermal, and mechanical forces to simulate the formation of plasma channels within rocks due to high-voltage electric pulses. The model’s accuracy is verified through field tests, and the results indicate that the configuration of the high-voltage pulse waveform, electrode spacing, and conductor particles within the rock impact the pathway of plasma channel formation. Prior to the formation of the plasma channel, minimal changes are observed in temperature and stress levels, with the majority of electric pulse energy dedicated to the creation of the plasma channel. Following the establishment of the plasma channel, the application of the electric pulse continues, resulting in notable alterations in temperature and stress levels. When the duration of the action reaches 105 ns, the temperature and stress levels surpass 104 K and 50 MPa, respectively, leading to fracture and extensive damage to the rock. The outcomes derived from the numerical model’s calculations can help to facilitate the cross-integration between physics and civil engineering and contribute to a deeper understanding of the rock fragmentation process under high voltage electric pulses.

An optimized synchronous approach to DC/DC droop backstepping control considering voltage compensation in DC microgrids

This paper addresses the impact of widely distributed power electronic loads and their constant power operations on the stability of DC microgrids. A backstepping controller, based on droop control, is proposed as a solution for mitigating the issues of constant power load in these grids. The unique feature of this controller is its independence from inter-device communication, which enhances the expandability and scalability of the DC microgrid. To tackle the challenge of power side converters needing a subsequent level DC/DC converter for voltage adjustment, a synchronous optimization method is introduced. This method, incorporating voltage compensation, keeps track of local output power during system transients. It identifies when the droop coefficient ratio deviates from proportionality, using this deviation as the initiation point for algorithm optimization. This approach modifies the local droop curve, enabling synchronous optimization. Before being optimized, the controller under heavy load conditions cannot meet the requirements of maintaining bus voltage and accurately allocating power simultaneously. However, after optimization, the system can maintain bus voltage while still ensuring accurate power allocation after disturbances. Moreover, the controller before optimization requires a secondary DC/DC converter to transfer electrical energy from the variable DC bus to the main bus. The optimized controller can effectively eliminate voltage offset and directly connect the DC/DC converter to the main bus, eliminating the cost problem caused by the secondary converter.

Gaussian bare-bones Levy circulatory system-based optimization for power flow in the presence of renewable units

The Optimal Power Flow (OPF) is a vital issue in electrical networks to ensure the economical and safe operation to transfer electrical energy that is very complex, non-linear, and limited. In the electrical networks with Renewable Energy Sources (RES), the OPF problem is a much more complex and constrained optimization problem because incorporating the intermittent nature of RESs, including Wind Turbine (WT) and Photovoltaic (PV), which have been used in this article, and OPF is often used to optimize various problems. In this research, an effort has been made to modify and improve the performance of a new algorithm named Circulatory System-Based Optimization (CSBO) to a more powerful algorithm for complex OPF problems, and the result of this research was to present a more effective and powerful algorithm named Gaussian Bare-bones Levy CSBO (GBLCSBO). CSBO mimics the mating behavior of the circulatory system in the body. The IEEE 30-bus and 118-bus test networks are adopted to validate the capability of the suggested approach in minimizing four objectives, which include the total generation cost, voltage deviation, power loss, and pollution emission.Finally, to know the performance and strength of GBLCSBO for solving various OPF problems, several new powerful algorithms include Seagull Optimization Algorithm (SOA), Teaching-Learning-Based Optimization (TLBO), Gray Wolf Optimizer (GWO), Multi-Verse Optimizer (MVO) have been used to compare with GBLCSBO. Also, the CEC 2017 test functions were used to measure the performance of GBLCSBO in a broader range of optimization problems.The optimization results in both topics of OPF problems and various test functions compared with various algorithms showed that GBLCSBO is both strong and robust and has a suitable and comparative performance in a wide range of different optimization problems such as OPF. According to the obtained results, the GBLCSBO demonstrates high potential in solving OPF problems.

PV-based DC-DC buck-boost converter for LED driver

PV-based power generation is implemented in many places due to the exhaustion of carbon-based fuels and ecological challenges. The solar panels for electric power generation along with the battery for storing the extra power will help society during the future demand. This paper analyzes a tri-port converter and designs it for buck-boost operation using inductors and switches in the circuit. The voltage converter is designed to have electric Energy transfer from solar panel to LED lamp, solar panel to battery and battery to LED lamp. The voltage ratio of the proposed buck-boost voltage regulator is designed to be more as compared with the conventional buck-boost converter. Also, the proposed buck-boost Voltage regulator output voltage polarity is found to be the same as compared to the input voltage. The working battery is developed to have a bi-directional power flow to deliver power to the LED lamp and to store power from the solar panel. The switches are operated alternatively and make the mode of operation strategy simple. The design of the converter stability analysis of the system using a bode plot is done. The experimental results acquired from the prototype validate the design of the converter.

Peningkatan Pemahaman Siswa Dalam Pembelajaran IPA Materi Konsep Listrik Melalui Penggunaan Alat-Alat Listrik Di Kelas VI Sekolah Dasar

This study entitled "Improving students' understanding of science learning about the concept of electricity through the use of electrical tools in class VI of SD Negeri Pudakpayung 01, SD Negeri Pudakpayung 02, SD Negeri Pudakpayung 03". The focus of the problem of improvement in this report is (1) students' low understanding of the concept of electricity (2) students pay less attention to learning. (3) Students do not understand the daily test questions so that their scores are low. The objectives to be achieved from this research are (1) To describe the use of electric tools to increase student learning interest about "Presenting information about the transfer and change of electrical energy" in class VI students. (2) To analyze the impact of the use of electric teaching aids in science learning on improving the learning outcomes of class VI students. (3) To analyze the impact of the use of electric tools on science learning in increasing students' interest and attention to learning. This research begins with the teacher's perceived problems in learning. The activity is continued by analyzing and formulating problems, then planning research in the form of corrective actions, observing, and reflecting on the actions taken repeatedly ending until the level of student completeness can be achieved. From the results of the analysis and conclusions obtained from this study are (1) Learning by using concrete media in the form of electrical tools can increase the activity and involvement of grade VI students in learning science as the basic competency "Presenting information about the transfer and change of electrical energy". (2) The use of concrete visual aids in the form of electrical tools can increase students' understanding of class VI in science learning the basic competence "Presenting information about the transfer and change of electrical energy" (3) Through experimental and demonstration methods using electrical tools it turns out to be able to improve learning outcomes of class VI students in science learning basic competency "Presenting information about the transfer and change of electrical energy"

Voltage profile improvement and power loss minimization of new haven injection substation for optimal placement of DG using harmony search algorithm optimization technique

The main importance of a power grid is to transfer electrical energy from the production to the consumption, while maintaining an acceptable reliability and voltage quality for all customers. The role of electrical power distributions to have centralized plants distributing electricity through Distributed Generation (DG) which reduces the Power Loss on transmission and distribution station and also improve voltage profile by optimization. This research work analyzes New Haven injection substation for optimal placement of DG generation based on wind power renewable energy source to the Distribution network and voltage stability using Harmony Search Algorithm. The model developed was simulated using MATLAB/SIMULINK software. The work applied new improved Harmony Search Algorithm for integration of renewable energy generation in the distribution network with positive impact on the operation of the voltage stability between 0.95 to 1.05p.u and reactive power distribution improvement through minimization of line losses. The total power system Loss without and with DG are 338.712KW and 307.9KW. Also, the voltage profiles of the sixteen faulty buses are stabilized for efficient performance of substation. Hence, the percentage of power system improvement is 27.23%. Therefore from the results, there is reduction of power Loss when DG is applied and optimised in the power system.

Enhancement of underwater shock wave by coupling electrical explosion and al-powder-suspension combustion: Facing advanced reservoir stimulation technology

The development of fossil energy requires eco-friendly and high-efficient approaches, especially in contemporarily low-carbon scenarios. Using the high-power pulsed discharge to induce fractures has drawn increasingly academic and industrial attention in reservoir stimulation. Therein, the electrical wire explosion is commonly adopted as the pulsed discharge load to transfer electrical energy to mechanical one (shock wave and plasma bubble) efficiently. To strengthen mechanical loadings, a discharge capsule with a metallic wire inside Al-powder suspension has been designed and tested. Experiments were performed with a μs-timescale pulsed power source with stored energy from 150 to 750 J, and the electrical explosion were diagnosed via high-speed photography, electrophysical, and mechanical measurements. The experiment shows that there is an optimal concentration of Al-powder suspension in order to obtain the maximum peak pressure of shock wave for a given discharge condition. Too high or low concentrations of the aluminum powder will cause a lower peak pressure. This paper shows that at the stored energy of 500 J, when the concentration of Al-powder suspension is 20 g/L, the peak pressure can reach 4.81 ± 0.27 MPa, which is 2.01 times as large as the shock wave generated by the electrical explosion under the same conditions in pure water. Through the electrophysical measurement, it is found that the aluminum powder almost does not affect the phase transition of the wire. However, in the subsequent plasma formation, the gaseous reaction products make the discharge channel more complex and in a higher pressure density state, which is shown by the increase of channel resistance. Through the backlit images taken by the high-speed camera, it is obvious that two discrete strong shock waves can be seen in the Al-powder-suspension environment.

Evaluation of the limiting conditions for operation of a large electrochemical energy storage system

In the last decade, a considerable role has been given to the development of renewable energy sources (Gielen et al., 2019) [1]. However, the unsteadiness of the wind load and insolation is a significant constraint for the transition to non-conventional renewable energy sources (NCRES) - wind turbines and solar panels (Barra et al., 2021) [2]. The use of energy storage systems (ESS) is a necessary factor in the energy transition (Ademulegun et al., 2021) [7]. However, the electrical energy transfer from typical electrochemical energy storage devices to the consumer is accompanied with the dissipation of part of this energy as heat (Henke et al., 2020) [26]. For this reason, it is advisable to assess the overheating of such storage devices, which may lead to a significant decrease in capacitive and resource characteristics (Collath et al., 2022) [43], and in some cases even to ignition and explosions (Murarka et al., 2022) [44]. The article defines the limiting conditions for the operation of electrochemical energy storage devices in a typical autonomous local energy system.

AgCu/TiO2 hot-electron device for solar water splitting: the mechanisms of LSPR and time-domain characterization

More and more metal/semiconductor nanostructures have been served as a hot-electron device with the localized surface plasmonic resonance (LSPR) effect to boost hydrogen evolution from solar water splitting. In this work, bimetallic AgCu with optimal ratio are deposited onto TiO2 nanopore/nanotube arrays to construct AgCu/TiO2 photoanode for photoelectrochemical water splitting, a novel simulation characterization to visualize the LSPR process is proposed. The near electric field enhancement and plasmon resonance energy transfer mechanisms of single Ag and Cu are inferred by time-domain characterization, illustrating the contradictory photocurrent under AM 1.5 illumination with its LSPR effect based on the particle size. The variation of local electric field over time within the interfaces of AgCu bimetals and bimetal/TiO2 models reveals the migration of hot electrons from Ag into Cu and the synergetic effect of different LSPR mechanisms. The resulting higher photoelectrochemical activities of AgCu/TiO2 also verifies the positive roles of the coexistence of AgCu on electron generation and energy transfer to interband excitation of TiO2.

Augmented random search based inter-area oscillation damping using high voltage DC transmission

The high voltage DC (HVDC) Transmissions are under rapid development all over the world. The HVDC transmission not only provides a low-loss electric energy transfer path, but also acts as an alternative tool for damping inter-area oscillations in modern electric power systems. In this paper, we proposed a novel reinforcement learning based HVDC oscillation damping controller using the augmented random search (ARS) algorithm. By leveraging the wide-area information such as voltages, phase angle, machine speeds, the ARS was able to determine the modulation power of HVDC to effectively damp inter-area oscillations. The proposed research overcomes the challenges of setting optimal controller parameters of the HVDC under various system transient events. The proposed ARS-based HVDC power oscillation damping control approach was tested on a simplified Western American large-scale power system model called minniWECC. Extensive studies have demonstrated the superiority of the proposed ARS-based HVDC control approach over conventional power oscillation damping methods.

Distributed reinforcement learning energy management approach in multiple residential energy hubs

Energy management optimization in residential buildings plays an essential role in addressing the problem of energy crisis in the world. This paper introduces a novel method to optimize the energy scheduling for multiple residential buildings in an interconnected framework through transferring energy concepts. To this end, a distributed reinforcement learning energy management (DRLEM) approach is proposed to manage the energy scheduling in multi-carrier energy buildings. In such facilities, equipped with the micro-combined heat and power (micro-CHP) and the gas boiler, the possibility of heat and electrical energy transfer among energy hubs is provided. The effectiveness of the proposed method is verified in a test residential interconnected energy hubs (EHs). Results show a noticeable improvement in energy costs while transferring energy concept is available. In a test frame consisting of three residential EHs, the proposed DRLEM approach in an interconnected mode leads to a daily cost reduction of 3.3% and wasted heat energy decrement of about 18.3% in a typical day compared to the independent mode. Furthermore, in peak tariff energy hours, EHs tend to share their produced excess energy about 23% more than low tariff energy hours to reduce overall energy price.

Research on Broadband Matching Method for Capacitive Micromachined Ultrasonic Transducers Based on PDMS/TiO2 Particles.

The study of impedance matching between a transducer and its working medium is an important part of acoustic transducer design. The traditional quarter wavelength matching (Q-matching) scheme is not suitable for broadband capacitive micromachined ultrasonic transducers. To mitigate this issue, a 0-3 composite broadband matching layer based on polydimethylsiloxane (PDMS) substrate/TiO2 particles is designed to achieve electrical insulation and efficient acoustic energy transfer of underwater capacitive micromachined ultrasonic transducer (CMUT) devices. In this work, the coherent potential approximation model is used to analyze the properties of 0-3 composite materials. Samples are prepared for performance testing to determine the proportion of TiO2 particles that enable the 0-3 composite materials to have the same longitudinal acoustic impedance as water. The CMUT device is packaged by a spin coating and pouring process, and its performance tests are carried out. The experimental results show that the central frequency of the transducer remains at 1.74 MHz, the -6 dB fractional bandwidth increases from 97.3% to 100.3%, the 3 dB directional main beam width increases from 8.3° to 10.3°, the side lobes decrease significantly, and the device has good reception sensitivity. These values imply that the 0-3 composite material has good matching performance, and this matching scheme has the advantages of high efficiency and wide bandwidth. This broadband matching method endows CMUTs with great advantages in underwater detection systems, and it facilitates underwater ultrasonic imaging of CMUT.