Charging Current Research Articles

"Next-Generation Four-Port Isolated Pv Ev Charger with Integrated Ac and Dc Charging Solutions"

This research introduces a pioneering 4-port isolated photovoltaic (PV) based electric vehicle (EV) charger designed to support both alternating current (AC) and direct current (DC) charging. The integration of four ports enhances charging flexibility and efficiency, catering to the evolving needs of electric vehicle users. The system harnesses solar energy through photovoltaic panels, ensuring a sustainable and eco-friendly charging solution. The isolation mechanism ensures safe and reliable charging by preventing ground loops and minimizing electrical hazards. By accommodating both AC and DC charging, the charger adapts to various EV models, offering a versatile and future-proof solution. This research contributes to the advancement of renewable energy integration into transportation infrastructure, promoting cleaner and more resilient mobility options in the growing electric vehicle market. DOI: https://doi.org/10.52783/pst.798

Self-Healable, High-Stability Anode for Rechargeable Magnesium Batteries Realized by Graphene-Confined Gallium Metal.

In this work, a self-healable, high-stability anode material for rechargeable magnesium batteries (RMBs) has been developed by introducing a core-shell structure of Ga confined by reduced graphene oxide (Ga@rGO). Via this Ga@rGO anode, a specific capacity of 150 mAh g-1 at a current of 0.5 A g-1 stable up to 1200 cycles at room temperature and a specific capacity of 100 mAh g-1 under an ultrahigh current of 1 A g-1 stable up to 700 cycles at a slightly elevated temperature of 40 °C have been achieved. Additionally, the ultrahigh rate, high-cycling stability, and long-cycle life of the anode are attributed to the stabilized structure; such a low-cost, simple, and environmentally friendly direct drop coating (DDC) method is developed to maximize the original state of the active materials. Remarkably, the self-healing ability of anodes is still presented under the ultrahigh charging current. This anode is promising for the development of high rate and high stability RMBs.

Development and functional testing of battery management system algorithm for an electric bicycle using hardware in the loop testbench

An embedded Battery Management System (BMS) ensures the effective functionality and longevity of the vehicle battery systems. Testing the BMS using the Hardware in Loop (HIL) approach effectively increases safety and reduces product development time in the manufacturing sector. This research aims to develop an efficient battery management system with two-level protection for electric bicycles and test its functionality in the HIL configuration. The bicycle traction model and battery management system were first developed using a model-based design. Further, the model is tested and validated using battery emulators in the HIL methodology. The battery management system receives input data, such as current, voltage, and temperature, and monitors these parameters. The first level of protection involves the vehicle user receiving the warning when the monitoring parameters values exceed the given first safety threshold. As per the second safety threshold values, the BMS trips off the charging or discharging process when the voltage is 51V, the charge current is 5A, the discharge current is -5A and the IC temperature is 80 degrees. Also, BMS balances the cells in 3.84 min using passive balancing. Additionally, the BMS delivers a controlled current of 2.5A for safe battery charging. This methodology increases safety by reducing the potential risks of testing the BMS algorithms in the actual electric bicycle.

Recycling drop-off centre: can it have an effect?

Municipalities in Greece hold the responsibility for establishing and organizing Green Points (a type of recycling drop-off centre), as mandated by law to have at least one within their jurisdiction. The aim of this study was to assess the recycling habits and opinions of the residents of the city of Larissa, with a specific focus on the potential impact of introducing a Green Point within the municipality area. Finally, a comparison was carried out to examine the differing viewpoints of individuals who recycle and those who do not, as well as the potential effects of a Green Point on them. A web-based qualitative questionnaire with closed-ended questions was deployed for the analysis. The key questions in the survey were clearly answered by 213 participants, providing strong indications. The local community is actively involved in recycling efforts and is generally satisfied with the current related system, but they feel that changes must be made. Although almost all the participants held a positive opinion on the potential location of a Green Point in their city, the majority of them disagreed with a potential increase in the current waste charges to support the operation of the Green Point. Non-recyclers cited time and space constraints as the primary reasons for not participating. The general consensus among participants is that a financial reward and/or fine can serve as a viable motivator for recycling. The primary distinctions between recyclers and non-recyclers are reflected in their beliefs about how powerful these motivators can be and how much they would increase the travel distance for recycling in the case of their existence.

Prescription charge policy acceptance among UK adults with and without long-term health conditions: a mixed-method survey

ObjectivesSince their introduction in 1952, per-prescribed item charges in England have continually risen. This study investigated the acceptability and impact of per-prescribed item charges, and awareness and use of initiatives...

Switching regulator based on an adaptive DC-DC buck converter for a lithium-ion battery charging interface

A switching regulator based on an adaptive DC-DC buck converter for a Li-ion battery charging interface is introduced in this paper with the aim of improving the efficiency of charging the Li-ion battery during the whole charging process. By using the battery voltage as feedback, an adaptive reference is generated. This reference is employed by the converter, which is in continuous conduction mode (CCM), to produce a wide adaptive output voltage that closely tracks the battery voltage, intended to serve as the power source for the multimode charging interface. The converter was implemented in a 180 nm complementary metal oxide semiconductor (CMOS) process and simulated using the Cadence Virtuoso tool. With an input voltage of 5 V and a switching frequency selected at 500 kHz, the simulation results show that the converter produces different charging currents for each battery charging mode, and an adaptive output voltage ranging from 2.8 V to 4.38 V, with the current ripple of 38 mA in CC mode and voltage ripple factor less than 1% in constant voltage (CV) mode. The average converter efficiency is 83.5%.

Temporary changes in current flow mechanisms in erbium-doped porous silicon

The paper discusses the basic mechanisms of conductivity in silicon MIS structures. The object of the study is porous silicon doped with an erbium impurity of an aqueous solution of erbium nitrate Er(NO3)3 • 5H2O by temperature annealing in a diffusion furnace at a temperature of 800°C for 1 hour. Comparative characteristics of the current-voltage and capacitance-voltage dependences are presented, describing the regular changes in the mechanisms of current flow and charge capture in the samples under study. The results of the work qualitatively and quantitatively describe the temporary change in the electrical characteristics of porous silicon, which can be taken into account by technologists for better understanding the mechanisms of current transfer in luminescent structures of porous silicon with erbium ions, as well as in the study and manufacture of light-emitting diodes based on it.

Influence of the magnetic field on the shunt resistance of an n+p-p+ silicon solar cell in the frequency modulation

A photovoltaic cell is a device that generates electricity directly from visible light. Several factors affect the conversion efficiency of solar cells. Parasitic resistances such as the shunt resistance is a fundamental parameter of the equivalent electrical model of the solar cell, which induces the leakage current of electrical charges when its value is low. It represents all leakage currents within the solar cell. It is also an indicator of good or poor quality of a solar cell, since a high value indicates low leakage current through the cell, and vice versa. A number of measurement techniques are used to determine the leakage current, in particular electrical current and voltage.

Influence mechanisms of ultraviolet irradiation aging on DC surface discharge properties of silicone rubber in dry and humid air

In the modern DC electrical transmission system, high-energy photons interact with silicone rubber (SIR) chains during long-term ultraviolet (UV) irradiation, it degrades the surface properties and triggers surface discharge (flashover) along the SIR-air interface, threatening the secure operation of the advanced electrical equipment. To further comprehend how UV-aging influences the flashover performance, in this work, the chemical bonds, surface charge transport parameters, and flashover performance of UV-aged SIR samples are characterized, and the influence mechanisms of UV-aging on surface discharge in dry and humid air are comprehensively clarified through the investigation from “molecular-mesoscopic-macroscopic” scales. The results indicate both degradation and oxidization reactions occur during UV-aging. The degraded molecular chains dominate the discharge in dry air, while oxidization reactions determine the discharge in humid environment: The degradation reactions reduce the surface trap depth and increase surface conductivity, leading to large surface leakage current and surface charge dissipation rate, causing flashover voltage in dry air increases and decreases as UV-aging time increasing. The oxidization of the chains introduces –OH and –COOH groups into chains, enhancing permittivity and adsorbing H2O molecules, significantly increasing surface leakage current, causing surface discharge voltage in humid air to decrease as UV-aging time increases.

IoT-based real-time analysis of battery management system with long range communication and FLoRa

In the current scenario, the world is focused on renewable energy generation to achieve sustainability by 2030 regarding clean and affordable energy. Lithium-ion (Li-ion)-based Battery Energy storage (BES) is a prominent approach that is widely adopted for managing large-scale renewable energy generation. Battery Management Systems (BMS) play a critical role in optimizing battery performance of BES by monitoring parameters such as overcharging, the state of health (SoH), cell protection, real-time data, and fault detection to ensure reliability. Previous studies have concluded that the implementation of Internet of Things (IoT) with LoRa ensures effective real-time monitoring of the BMS of Li-ion batteries. This study proposed and implemented a customized LoRa and IoT-based hardware system with a gateway to acquire parameters such as terminal voltage, current, charge voltage, charge current, cycle, temperature, state of charge (SoC), and SoH, and log them into the cloud server. An OMnet++-based Framework for LoRa (FLoRa) simulation was implemented to analyze the power consumption and residual energy of the customized LoRa nodes. The simulation was configured with a spread factor of 7, a carrier frequency of 433 MHz, a bandwidth of 125 KHz, and a transmission power of 2 dBm. The simulation results indicated that Node 3 had the highest mean power consumption (0.028233) and total energy consumption (0.146592), whereas Node 0 exhibited the lowest mean power consumption (0.023413) and total energy consumption (0.070204). Additionally, a comprehensive dataset encompassing voltage, current, and time was created and utilized for precise calculations of the battery's capacity and state of health, with potential use in future predictions.

Impact of potential and temperature fluctuations on charge and heat transport in quantum Hall edges in the heat Coulomb blockade regime

We present a broad study of charge and heat transport in a mesoscopic system where one or several quantum Hall edge channels are strongly coupled to a floating Ohmic contact (OC). It is well-known that charge-current fluctuations emanating from the OC along the edge channels are highly susceptible to the OC charge capacitance in the heat Coulomb blockade regime (an impeded ability of the OC to equilibrate edge channels). Here, we demonstrate how potential and temperature fluctuations due to finite OC charge and heat capacities impact the heat-current fluctuations emitted from the OC. First, by assuming an infinite OC heat capacity, we show that the output heat-current noise is strongly dependent on the OC charge capacitance, following from a close relation between one-dimensional charge and heat currents. When also the OC heat capacity is finite, an interplay of potential and temperature fluctuations influences the heat transport. Concretely, we find that the effect of the charge capacitance on heat transport manifests in terms of a strongly increased energy relaxation time in the heat Coulomb blockade regime. Furthermore, we find expressions for a broad set of output observables, such as charge and heat auto- and cross correlations, as functions of input and OC fluctuations, depending on the relation between charge and energy relaxation times compared to the frequency of fluctuations and inverse (local) temperatures as well as on the number of edge channels attached to the OC. Finally, we show that a finite OC heat capacity transforms the full counting statistics of the output charge from Gaussian to non-Gaussian. Our findings provide opportunities to experimentally probe and harness the quantum nature of heat transport in strongly coupled electron circuits. Published by the American Physical Society 2024

Prospects for measuring the time variation of astrophysical neutrino sources at dark matter detectors

We study the prospects for measuring the time variation of solar and atmospheric neutrino fluxes at future large-scale xenon and argon dark matter detectors. For solar neutrinos, a yearly time variation arises from the eccentricity of Earth’s orbit and, for charged current interactions, from a smaller energy-dependent day-night variation due to flavor regeneration as neutrinos travel through Earth. For a 100-ton xenon detector running for ten years with a xenon-136 fraction of ≲0.1%, in the electron recoil channel a time-variation amplitude of about 0.8% is detectable with a power of 90% and the level of significance of 10%. This is sufficient to detect time variation due to eccentricity, which has amplitude of ∼3%. In the nuclear recoil channel, the detectable amplitude is about 10% under current detector resolution and efficiency conditions, and this generally reduces to about 1% for improved detector resolution and efficiency, the latter of which is sufficient to detect time variation due to eccentricity. Our analysis assumes both known and unknown periods. We provide scalings to determine the sensitivity to an arbitrary time-varying amplitude as a function of detector parameters. Identifying the time variation of the neutrino fluxes will be important for distinguishing neutrinos from dark matter signals and other detector-related backgrounds and extracting properties of neutrinos that can be uniquely studied in dark matter experiments. Published by the American Physical Society 2024

Giant spin caloritronic properties in spin-semiconductor graphene nanoribbons via zigzag edge extensions

In this work, we theoretically studied the spin caloritronic properties of 7-width armchair graphene nanoribbons with isolated zigzag edge extension (D-system), cove-to-zigzag edge extensions (D1-system), cove-to-cove edge extensions (D2-system), and zigzag-to-zigzag edge extensions (D3-system), respectively, by combining first-principles calculations with a non-equilibrium Green's function method. The results illustrate that the D-system and D1-system with sublattice imbalance show spin-semiconductor properties and obtain thermally induced pure spin current devoid of charge current due to the symmetric spin-up and spin-down channels around the Fermi level. Additionally, it observes substantial spin-dependent Seebeck coefficients Ssp, approximately −2.5 mV/K for the D-system and −3.0 mV/K for the D1-system, near chemical potential ±0.5 eV. More than that, the D1-system showcases a remarkable spin-dependent thermoelectric figure of merit, ZspT, at room temperature, approximately approaching 8 near the Fermi level. In contrast, the D2-system and D3-system only achieved charge-dependent thermoelectric figure of merit of about 0.5 due to the preservation of sublattice balance. Our findings provide important suggestions for designing spin caloritronic devices with high efficiency.

Bio-inspired vibration isolator with triboelectric nanogenerator for self-powered monitoring

Vibration isolators are used in many engineering projects, but their real-time monitoring and early warning still a challenge. This paper presents a novel bio-inspired vibration isolator with triboelectric nanogenerator (BVI-TENG), which can be applied on vibration isolation and structural health monitoring. To find the optimal combination of parameters to achieve quasi-zero stiffness, the relationships between the force–displacement and the stiffness-displacement are investigated. After establishing the dynamic model, the effects of the different parameters on the amplitude-frequency are explored by using the harmonic balanced method. To explore the vibration isolation performance, the force transmissibility is analyzed. It was found that BVI-TENG can isolate the low-frequency and even ultra-low frequency vibration. By setting up and testing the experimental prototype, the theoretical results are verified. The energy harvesting performance of BVI-TENG is investigated by analyzing the output current, output voltage and transfer charge under different frequency. By tuning the loading resistance, the maximum output power of BVI-TENG is found. More importantly, the structural health monitoring part of the BVI-TENG produces AC signal in the safe region, which can be harvested and stored, and the signal transforms immediately into DC signal when out from this region. The performances demonstrate that the BVI-TENG can be applied to vibration isolation and serves as a self-powered structural health monitoring device to meet the needs of the civil engineering, ocean platform, and industrial robot.

Probing the efficiency and mechanism of hydrogen permeation inhibition in pipeline steel by organic inhibitors

A hydrogen economy will require the use of steel pipelines to transport and store hydrogen. Methods and materials are urgently needed to prevent the embrittlement of steel pipelines in hydrogen service. In this work, we show that hydrogen permeation into pipeline steel can be mitigated by organic inhibitors, as demonstrated by a typical organic inhibitor benzotriazole (BTA) under simulated X65 steel pipeline cathodic protection conditions. Electrochemical and surface analytical techniques were used to probe the efficiency and mechanism of hydrogen permeation inhibition. In particular, a novel multi-electrode array method was designed to probe the inhibitor film by measuring local impedance and hydrogen charging currents. The ability and efficiency of BTA to inhibit hydrogen permeation were found to be closely associated with the formation and coverage of inhibitor films on steel surfaces. A model is proposed to illustrate the mechanism of hydrogen permeation inhibition by organic inhibitors.

Onsager relations between spin currents and charge currents

Onsager relations between spin currents and charge currents

Junction-Controlled-Diode-Embedded SiC-MOSFET for Improving Third Quadrant and Turn-On Characteristics

In this paper, we propose a novel 1200V SiC MOSFET featuring the embedded junction-controlled-diode (JCD-MOSFET) and demonstrate its static and dynamic characteristics through TCAD simulations. Without sacrificing blocking and conduction performance, the adoption of JCD can effectively reduce knee voltage to 1.7V based on unipolar carrier conduction mode. Due to the reduced peak reverse recovery current and reverse recovery charge, the JCD-MOSFET achieves 30.8% lower turn-on losses than conventional MOSFET. Meanwhile, the fabrication process for the JCD-MOSFET is the same as conventional MOSFET without an extra mask. This proposed JCD-MOSFET prototype shows great potential in target applications in the near future.

Corrosion behavior of predominant Halodesulfovibrio in a marine SRB consortium and its mitigation using ZnO nanoparticles

Formation of Sulfate Reducing Bacteria (SRB) biofilm accelerates microbiologically influenced corrosion (MIC). The aim of this study was to investigate both the corrosivity of a marine SRB consortium on carbon steel coupons and its mitigation in the presence of ZnO. Metagenomics analysis revealed that Halodesulfovibrio (78.9%) was predominant and could be related to MIC. The analysis also showed a remarkable shift from a highly corrosive SRB consortium in the control bioreactors to a far less corrosive consortium when ZnO was added to the bioreactors. Further results indicated that the corrosion rate of the SRB consortium was 8.17 mpy on the carbon steel coupons. In the ZnO-treated bioreactors, the count of SRB and MIC in the carbon steel coupons simultaneously reduced. Moreover, Confocal Laser Scanning Microscopy and profilometry analysis determined that ZnO could significantly decrease the amount of biofilm and the corrosion rate. Electrochemical experiments revealed higher corrosion current density (icorr) and lower charge transfer resistance (Rct) in the control bioreactors relative to the ZnO-treated bioreactors. We introduce Halodesulfovibrio as a potentially important corrosive genus in a marine SRB consortium. Additionally, ZnO could be considered a proper candidate to control the corrosion induced by Halodesulfovibrio.

One-loop analysis of β decays in SMEFT

We perform a loop-level analysis of charged-current (CC) processes involving light leptons and quarks within the Standard Model Effective Field Theory (SMEFT). This work is motivated by the high precision reached in experiment and Standard Model calculations for CC decays of mesons, neutron, and nuclei, and by a lingering tension in the Cabibbo universality test. We identify the SMEFT operators that induce the largest loop-level contributions to CC processes. These include four-quark and four-fermion semileptonic operators involving two third-generation quarks. We discuss the available constraints on the relevant effective couplings and along the way we derive new loop-level bounds from K → πνν¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\pi \ u \\overline{\ u} $$\\end{document} on four-quark operators involving two top quarks. We find that low-energy CC processes are quite competitive with other probes, set constraints that do not depend on flavor-symmetry assumptions, and probe operators involving third-generation quarks up to effective scales of Λ ≃ 8 TeV. Finally, we briefly discuss single-field ultraviolet completions that could induce the relevant operators.

Longitudinal kinematic imbalances in neutrino and antineutrino interactions for improved measurements of neutrino energy and the axial vector form factor

Current and future accelerator neutrino oscillation experiments require an improved understanding of nuclear effects in neutrino-nucleus interactions. One important systematic uncertainty is introduced by the collective impact of nuclear effects which bias the reconstruction of the neutrino energy, such as the nuclear removal energy. In this manuscript, we introduce a novel observable for accelerator neutrino oscillation experiments, the visible longitudinal momentum imbalance, reconstructed in charged-current quasielastic interactions from the outgoing charged lepton and nucleon. We demonstrate it to be minimally dependent on the neutrino energy and sensitive to sources of bias in neutrino energy reconstruction. Furthermore, we show how the use of the longitudinal imbalance in antineutrino interactions in a target containing hydrogen allows for an improved, high-purity selection of the interactions on hydrogen. This approach offers the potential for precise measurements of the nuclear axial vector form factor as well as of the antineutrino flux. Published by the American Physical Society 2024