Maximum Current Value Research Articles

Study on the effect of pitching on wave energy converter devices due to a spring constant of 980 N/M

Having enough energy is crucial to living a healthy and fulfilling life. Energy is necessary for many of the actions and tasks that individuals carry out regularly. To increase national resilience and enhance the welfare of its citizens, Indonesia is thought to be a good place to use renewable energy through the development of its natural resources. The Wave Energy Converter is one of the energy producers (WEC). The Wave Energy Converter is a machine that uses the up-and-down motion of a chain through a pontoon to drive the rotation of a solenoid in a generator to produce electrical energy. The component that produces energy is the vertical movement of waves. Thus, the impact of the spring constant on ocean waves is examined in this work. Both planetary and non-planetary approaches were used in this study. Based on the research objectives and the experimental results on the pitching motion performance of the Wave Energy Converter machine, it can be concluded that the power without planetary gear in the analysis of potential energy and sea data identification is 0.43 Volts, and the highest is 4.2 Volts. The RPM range is 78.18 RPM at the minimum and 91.45 RPM at the maximum. 0.021 amps is the minimum and 0.043 amps is the maximum current value. The power range for planetary gear potential energy analysis and sea data identification is 58.5 volts to 168.36 volts. The RPM range is 78.18 RPM at the minimum and 91.45 RPM at the maximum. 1.93 amps is the least current value, and 14.01 amps is the maximum

Disturbance observer‐based finite‐time control of a photovoltaic‐battery hybrid power system

AbstractHerein, the load power control of the stand‐alone photovoltaic‐battery hybrid power system (HPS) has been investigated. The underlying HPS consists of a boost DC‐DC converter, a non‐isolated bidirectional half‐bridge converter, a photovoltaic (PV) panel, and a battery pack. On the PV side, a disturbance observer‐based finite‐time terminal sliding mode control (FTSMC) is used to regulate the DC bus to the desired voltage, in the presence of irradiation variation and load changes. On the battery side, the load power control system is constructed, based on a model predictive control (MPC) algorithm, with constraints on state‐of‐charge (SOC) and maximum current value of the battery to improve the battery life cycle and high reliability of the system. To highlight the benefits of the closed‐loop system, the analytical proofs and numerical analysis are presented from a comparative viewpoint. The experimentally derived results, by implementation on TMS320F28335 digital signal processing (DSP), are also presented and discussed for practical justification.

Exploring photocurrent effects as a function of CdS shell in ultrasmall quantum dots

In this study, we report the photocurrent effects in CdSe/CdS ultrasmall quantum dots (USQDs). The photocurrent effects can be observed when photons with energy higher than the band gap energy illuminate the USQDs, generating of charge carries. Here we use two types of USQDs to analyze these effects: CdSe and CdSe/CdS core/shell. The Raman spectrum was used to confirm the presence or absence of the shell. The CdSe USQDs exhibited a photocurrent effect consistent with the pattern typically observed in semiconductor materials. The sample exhibited a rise time of 1.26 s when the light was turned on and a decay time of 0.70 s when the light was turned off, reaching a maximum current value of 12.90 pA. However, an overshoot phenomenon was observed in the CdSe/CdS USQDs when the light was turned off. This effect is related to the accumulation of charge carriers that appear when the USQDs are subjected to an electric field and the presence of light. Thus, this accumulation caused by the potential barrier formed by the shell is released when the light is turned off. The sample exhibited a rise time of 2.28 s when the light was turned on and a decay time of 2.59 s when the light was turned off, reaching a maximum current value of 70.51 pA. Therefore, we have demonstrated that it is possible to explore the photocurrent effects in CdSe/CdS USQDs.

An eco-friendly approach for bioelectricity production through microbial fuel cell using Musa acuminata as waste biomass

With the increasing population and industrialization, the demand of electricity is increasing day-by-day and high energy demands have adverse effects on fossil fuels consumption. The sustainable development goal (SDG) 7 focuses on green energy. Due to this, global attention is shifted from conventional sources to non conventional energy sources such as solar energy, wind energy, waste biomass, etc. This work explores the feasibility of a microbial fuel cell for bio-electricity production. The effect of different catholytes on bio electricity production is assessed. This research includes the fabrication of a H-shaped double chambered microbial fuel cell using two containers of 2 L each. Both the containers were connected with an agar salt bridge. The bioelectricity was produced from banana peel waste using potassium dichromate and potassium ferricyanide as catholyte and zinc rod and copper plate as electrodes. With potassium dichromate, the maximum value of voltage and current was found as 0.20 V and 0.112 mA respectively, while in case of potassium ferricyanide the maximum voltage and current obtained was 0.42 V and 0.55 mA respectively at 0.1 M concentration of catholyte. Substrates like glucose (10 % by weight) and sodium acetate (5 % by weight) was added in the banana peel slurry so as to make the microbial fuel cell more efficient. Further, impact of increase in potassium ferricyanide concentration from 0.1 to 0.5 M concentration on the generation of electricity was analysed and it was found that with increase in concentration of catholyte, voltage and current enhanced. The maximum voltage, current and power density found by increasing concentration of potassium ferricyanide from 0.1 to 0.5 M was 0.9 V, 3.36 mA and 1.055 W/m2. This study concludes that potassium ferricyanide is better oxidising agent than potassium dichromate. Microbial fuel cell can be a promising technology for bioelectricity production using banana peel waste.

Effect of Natural Dye Extracts on the Absorbance Characteristics of TiO2 in Dye-Sensitized Solar Cells

Natural dye extracts from Chinese Ixora (Ixora chinensis) flower, Cassod flower (Cassia Siamea), Cassava leaf (Manihot Esculenta), purple heart (Tradescantia Pallida) and Copper leaf (Acalypha Wilkesiana) have been explored as sensitizers for the fabrication of dye-sensitized solar cells. The properties of the dyes were investigated using the FTIR and they all showed broad absorption bands in the 3800 to 3000cm-1 wavelenght and strong presence of intermolecular H-bonds. The effect of dye extracts on the absorbance and transmittance features of TiO2 was well studied by the UV-VIS and the absorbance peak was in the case of sensitization with Manihot Esculenta seen to radically improve above 1.0 at 350nm wavelength. Finally, the current and voltage characteristics of the DSSC were studied in sunlight and at a peak sunlight intensity of 601m/w2, the Manihot and Cassod sensitized devices exhibited maximum voltage values of 115 and 84mV respectively and maximum current values of 4.32 and 2.99mA. These plants have shown great potential for application in fabrication of cost effective and environmentally friendly DSSCs.

Research on Leakage Current Waveform Spectrum Characteristics of Artificial Pollution Composite Insulator

In order to know about the change features of leakage current during the pollution flashover process of composite insulators, the study of the pollution flashover test on composite insulator under the pollutional condition is presented in the artificial fog cabinet. The characteristics of leakage current waveforms in time-domain and frequency-domain are measured and analyzed during the test. The analysis results show that there is a strong correlation among the fundamental harmonic, the third harmonic and fifth harmonic. The characteristics of leakage current spectrum are represented by the maximum value of leakage current (Im), total harmonic distortion (THD), and phase difference of fundamental leakage current (θ). During a near-flash event, the leakage current exhibits high amplitude, low harmonic content, and small phase difference between the fundamental leakage current and voltage. The research findings provide a basis for establishing a pollution flash warning system based on leakage current characteristic quantities.

A microfluidic study of acetate conversion kinetics in a microbial electrolysis cell: The role of age, concentration and flow on biofilm permeability

This work addresses the need for kinetic studies to identify potentially exploitable mechanisms involved in generating current from flow-based bioelectrochemical systems (BES). Unlike most kinetic studies, which focus on electron transport, we focus on chemical mass transport by controlling the relevant experimental parameters. This is accomplished using a microfluidic 3-electrode setup that recorded output current (I) from a mature Geobacter sulfurreducens electroactive biofilm (EAB) while accurate control is applied over acetate concentration ([Ac]) and flow rate (Q). Additionally, the flow mode (tangential and perpendicular) is controlled to apply expansive or compressive sheer forces against the EAB. A detailed analysis of the effects of the control variables on the current is based on data collected for nearly 1 year, the longest timeframe for a microfluidic BES experiment to date. All experimental parameters affect output, but we find that age is the dominant factor. After nearly 1 year, current densities were as high as 29.5 A m−1, which is higher than in any reported 3-electrode experiment on G. sulfurreducens EAB. We conclude that flow-based deacidification of the EAB led to increases to outputs during early growth stages, whereas at later times, the increases were related to improved EAB permeability to acetate. Additionally, after 5 months each flow mode provokes complementary kinetic properties based on measurements of apparent enzyme/substrate affinity (KM(app)) and maximum current (Imax) values. Therefore, in addition to providing fundamental insights into BES functionality, these findings also open the door to practical applications and offer a road map to further experimental optimization.

Development of a unique integrated bioreactor for simultaneous desalination and bioenergy and biohydrogen production

In the wastewater treatment challenge, it is really essential to develop integrated systems in reducing greenhouse gases, producing green energy and achieving sustainable development. In this regard, an integrated electro-biomembrane reactor was developed and performed in this study for simultaneous biohydrogen (bioH2) production from energetic poplar leaves using dark fermentation (DF) process, conventional H2 production, bioenergy production in the DF process, and saline water desalination in a single system. The results of this study showed that pH was the main controlling parameter in bioH2 production, and the superior production of 40.2 mL/g-biomass was obtained at a pH of 5.5. The maximum current and power density values were 2861.7 mW/m2 and 2819.4 mA/m2 at pH 5.5 under improved conditions. Furthermore, the maximum conventional H2 production was found to be 1341.6 mL using 2 M of KOH solution. Overall, the results further proved that the proposed integrated system can be a sustainable and promising process for industrial applications, considering its high desalination, energy production, and conventional and biological H2 production efficiencies.

The simulation study of high-performance micro-inductors Based on MEMS 3D coils

With the development of flexible electronics and microsystems, the demand for the miniaturization of electronic components is becoming increasingly urgent. Due to the advantages of miniaturization, low power consumption, and easy integration, the micro-inductors fabricated by microfabrication technology get more and more attention. However, the traditional two-dimensional inductors are no longer able to meet the growing needs of today’s society in terms of occupied areas, inductance values, and packaging costs. So, this paper proposes a three-dimensional structure thin film solenoid micro-inductor based on MEMS and analyzes it by using finite element method (FEM). The simulation focuses on recording the inductance values and quality factors of the micro-inductors with varying parameters in the frequency range of 0-2, 000 MHz. Additionally, the maximum current values corresponding to the micro-inductors with different parameters are recorded at the operating temperature of polyimide, specifically addressing the current-carrying capacity. The simulation result has certain theoretical guidance for high-performance micro-inductors design.

Hybrid battery energy storage for light electric vehicle — From lab to real life operation tests

The aim of the research presented in the paper is to improve the lifetime of lead-acid battery systems which are widely used in low-speed electric vehicles or utility vehicles, since the cycle life of lead-acid batteries is nonlinearly dependent on the depth of discharge and electrolyte temperature. The solution proposed here is to connect lead-acid batteries with a small lithium‑iron-phosphate battery using only a diode. This connection is simple and does not require the use of an actively controlled converter. The concept was tested at various levels of an experiment, from the initial calculation of cycle life improvement and simulation, through a laboratory experiment, all the way to operational environment tests. The results obtained confirmed the main assumptions of the study: decrease in the depth of discharge of lead-acid battery for the distance traveled of around 17 %—which would translate into a 30 % better cycle life according to the characteristics indicated by the producers—and decrease in the root mean square and maximum current values of lead-acid battery by around 40–50 % and 26 %, respectively. Range extension was also achieved in vehicles. The solution has been successfully introduced to the market and is now used in few light electric vehicles.

The Impact of Power Quality on VFD Application in Motor Fan Dust Collector

The technology to control the motor speed according to load requirements is variable frequency drive (VFD). The motor fan dust collector operates using a VFD to reduce the speed during idle smelting conditions. In addition to energy efficiency, the power quality of the electrical energy system is important to consider. Nonlinear loads from VFDs cause harmonics in the industry that affect electrical power. Power quality measurement and analysis to determine the harmonic and unbalance values of voltage and current are important for improving power quality. This paper discusses the effect of VFDs on power quality, as a real case study, data from existing VFDs in the steel industry are taken to analyze power quality. A large current harmonic of 45% occurs when the VFD decrease the motor speed during idle smelting operation and drops to 5% when the motor speed returns to full speed during smelting operation on. The average maximum current unbalance value is 10.8% and the voltage unbalance is 0.36%, which is still below the standard maximum limit whether the motor is at full or low speed.

Enhanced electron transport and optical properties of experimentally synthesized monolayer Si9C15: a comprehensive DFT study for nanoelectronics and photocatalytic applications.

Two-dimensional silicon-carbide (SixCy) materials stand out for their compatibility with current silicon-based technologies, offering unique advantages in nanoelectronics and photocatalysis. In this study, we employ density functional theory and nonequilibrium Green's function methods to investigate the electronic properties, electron transport characteristics, and optoelectronic qualities of experimentally synthesized monolayer Si9C15. Utilizing the modified deformation potential theory formula, we unveil Si9C15's significant directional anisotropy in electron mobility (706.42 cm2 V-1 s-1) compared to holes (432.84 cm2 V-1 s-1) in the a direction. The electrical transport calculations reveal that configurations with a 3 nm channel length demonstrate an ON state when biased, reaching a peak current of 150 nA. Moreover, this maximum current value escalates to 200 nA under tensile strain, marking an increase of approximately 100 times compared to the 5 nm channel, which remains in an OFF state. Si9C15 exhibits high light absorption coefficients (∼105 cm-1) and suitable band edge positions for water splitting at pH 0-7. Applying 1-5% tensile strain can tune the conduction band minimum and valence band maximum closer to the standard redox potentials, enhancing photocatalytic water splitting efficiency. Remarkably, under illumination at pH 0 and 7, Si9C15 can spontaneously catalyze water splitting, demonstrating its potential as a highly efficient photocatalyst. Our findings emphasize the importance of strain control and device length optimization for performance enhancement in nanoelectronics and renewable energy applications, positioning Si9C15 as a promising material for high-performance field-effect transistors and photocatalytic water splitting.

Generation of Current in Thermoelectric Generator by Absorption of Heat Using ANSYS Thermal

Thermoelectric power generation is a renewable energy conversion process that directly converts heat to electricity. This research proposes a novel fluid-thermal-electric multi-physics numerical model for predicting the performance of a thermoelectric-producing system. On the ANSYS platform, numerical simulations are done along with the exhaust temperature and mass flow rate. The range of hot end temperatures is from 100 to 450 degrees Celsius. Similarly, the cold end temperature can reach a maximum of 25 degrees Celsius and a minimum of 10 degrees Celsius. When the temperature at the generator's hot end rises, it means the temperature at the generator's cold end must fall. It means both have an inverse relation to each other. The maximum heat absorbed at the hot junction is 32.762 W and the minimum heat absorbed at the hot junction is 4.6305 W. Hence the maximum and minimum current values produced in this paper by the thermoelectric generator are 72.156 A & 10.816 A respectively. The hot side heat exchanger's position of the thermoelectric modules has a significant impact on output. Combining the benefits of many models are advised to construct an inclusive thermoelectric generator system for use in real-world applications.

Effect of coating type on electrode degradation and its life in resistance spot welding of a low carbon steel

In this study, the degradation occurring on the surface of the electrodes used in resistance spot welding of hot dip galvanized and galvannealed low carbon steels are examined and the life of the electrodes are tested. Several characterization studies are carried out on the surface and cross-sections of CuCrZr-based electrodes, following the life tests that are carried out according to SEP 1220 standard, and it is observed that a more convex degradation surface is formed on the electrode surface used in the welding of galvannealed steel compared to the galvanized one. This geometry indicates that the induced current is more stable. Depending on the increase in the number of spots, coating type and the amount of convexity, it is determined that the phases formed on the electrode surface also differ. Although the coating type has no significant effect on the welding strength value and no significant difference is observed in the maximum current values, a longer life is determined in the electrode used for the welding of galvannealed steel. It has been identified that the dominant mechanism affecting electrode life is the coating type, which is directly related to electrode degradation.

Anodic MAO coating formation on Ti-25Ta alloy

This study aims to produce an anodic layer using the micro-arc oxidation (MAO) technique on the Ti-25Ta alloy by changing the threshold current value in surface treatment processes (1.0, 1.5, 2.0, and 2.5 A). The MAO treatment processes were carried out by applying a voltage of 300 V for 60 s, and the maximum current value was changed. The results showed that increasing the current limit value resulted in an increase in the amount of rutile phase in the films, as well as an increase in the coating's thickness and contact angle. Furthermore, all coatings showed good adhesion with the Ti-25Ta substrate.

Enhanced Electricity Generation and Heavy Metal Removal by a Rutile–Biochar Cathode MFC

The issue of heavy metal pollution has gradually emerged as a significant global concern. Microbial fuel cells (MFCs) hold immense potential for clean energy production and pollutant treatment. However, their limited power generation efficiency hampers the large-scale implementation of MFCs. The porous microstructure of biochar and the excellent physical and chemical properties of rutile render both materials promising catalysts with positive potential. In this study, we employed biochar as a carrier for rutile to fabricate a novel rutile–biochar (Rut-B) composite material, investigating its efficacy in enhancing MFC power generation efficiency as a cathode catalyst, as well as its application in heavy metal pollutant degradation. Scanning electron microscopy (SEM) results confirmed the successful preparation of biochar-loaded rutile composites. The MFC achieved maximum current density and power density values of 152.26 mA/m2 and 9.88 mW/m2, respectively—an increase of 102.7% and 224% compared to the control group without the addition of Rut-B. Furthermore, the biochar-loaded rutile MFC exhibited excellent performance in degrading heavy metal pollutants; within 7 h, the Pb2+ degradation rate reached 92.4%, while the Zn2+ degradation rate reached 84%. These rates were significantly higher than those observed in the control group, by factors of 437.2% and 345%, respectively. The cyclic degradation experiments also demonstrated the outstanding stability of the system over multiple cycles. In summary, this study successfully combined natural rutile with biochar to create an efficient electrode catalyst that not only enhances electricity generation performance but also provides an environmentally friendly and cost-effective approach for remediating heavy metal pollution.

PENGARUH ARUS EKSITASI TERHADAP ARUS STATOR MOTOR SINKRON 3 FASA DENGAN VIRTUAL INSTRUMENT

The three-phase current value of a synchronous motor has a great impact on its long-term reliability and performance under load. Therefore, maintenance and monitoring must be performed to determine the performance of synchronous motors. A virtual instrument and its LabView software can be used as a method to determine the operating current value of a synchronous motor. The device used in the study contains a synchronous motor as a load, and his LabView-equipped controller is used to execute commands during synchronous motor testing. NI MyDAQ is used as an input to the controller prior to using LabView, so it can be customized for use as an input to motors and controllers. Power is supplied by adjusting the motor input voltage to 380 volts and the controller input voltage to 220 volts. The purpose of the research is to develop tools and simulation software for synchronous motors that use voltage regulators to react to variations and determine minimum and maximum voltage values to determine motor performance. As a result of examination, the motor output reached a maximum current value of 0.4A at idle and a maximum controller current value.

Pristine and modified silicene based volatile organic compound toxic gas sensor: a first principles study

In this work, we have investigated the sensitivity of two Volatile Organic Compounds (VOCs), formaldehyde (FD) and acetaldehyde (AD) on the surface of two-dimensional (2D) Armchair Silicene Nanoribbon (ASiNR) by analysing the structural, electronic and transport properties using density functional theory (DFT) and non-equilibrium Green's function (NEGF) formalism. Different models of ASiNR have been considered viz; pristine, Al-doped, P-doped, Al/P co-doped and vacancy-defected ASiNR. The findings revealed that the vacancy-defected models shows a significant increase in the adsorption energies for both VOCs compared to other models. Apart from that, in all the models, the current increases with the applied voltage and the maximum value of current was found in Al/P co-doped model at a higher bias voltage of 2 V. The variation of the computed transmission spectrum peaks from −2 to 2 eV of energy values also confirms the sensitivity of the proposed models towards the VOC molecules. Moreover, the projected device density of states (PDDOS) revealed that all the models remain semiconducting before and after adsorption, which completely agrees with the transmission spectrum. Furthermore, Al/P co-doped model shows high sensitivity of 68% and77% towards FD and AD molecules respectively. Thus, it is concluded that the modeled ASiNR VOC gas sensors will aid in sensing cancer.

Analisis Efektivitas Daya Dan Energi Pada Sistem Pembersih Solar PV 2 × 50 Wp dengan Metode Lateral Movement

The implementation of the solar cell itself often has problems in its operation. One of the factors that affect the performance of PLTS is that the dirty solar panel cover glass is covered with dust or dirt so that it blocks the intensity of sunlight entering the solar panel which results in a reduced output of the solar panel. A 2x50 Wp solar pv cleaning tool was made to overcome the problem of reduced solar pv output due to the influence of dirt adhering to the pv cover glass. The cleaning tool that has been designed is expected to maximize the quality of power and energy that will be generated by solar pv. The solar pv dirt cleaning tool is used on the research object of the PLTS system in the Renewable Lab, Navy Building, State Polytechnic of Malang. Making a cleaning tool design using Solidworks software, with the reason being able to get a 3D picture of the planned pv dirt cleaner. The cleaning tool works with the help of a battery/power supply as its electrical power. There are 3 dc motors connected to brushes, wheels and water pumps. The cleaning tool moves in a lateral movement (sideways movement) from corner to corner 3 times, then the brush rotates to clean the solar cell cover glass from dirt. In the cleaning process, it can be assisted by using water provided and sprayed by a water pump. The average Vmp and Imp values are 19.72 V and 1.64 A. From the Vmp and Imp values, the average Pmp calculation results are 32.60 W for solar pv after cleaning. Before cleaning, the average maximum voltage (Vmp) and maximum current (Imp) values are 18.43 V and 1.05 A. From the Vmp and Imp values, the average Pmp calculation is 19.65 W.

Characteristics and causes of voltage observed at the current feeder of high-temperature superconducting WISE conductor

The HTS (high-temperature superconducting) conductor is a feasible candidate for constructing magnets for next-generation fusion devices because of its higher critical current in a high magnetic field. A new concept of the HTS-WISE (Wound and Impregnated Stacked Elastic tapes) conductor has been studied aiming to apply the fusion reactor magnet. Here, the WISE-U conductor is composed of stacked thirty REBCO tapes (10 mm width, 65 μm thickness, I c = 370 A @77 K, s.f.) wrapped by a stainless-steel coil tube which is inserted into the metal pipe. The 4 m-long REBCO tapes are folded with a radius of curvature of 35 mm in a hairpin-like structure. A low-melting-point metal U-Alloy 60 whose melting point is 60°C is poured into the pipe for impregnation to make the non-insulation conductor. The REBCO tapes and the current feeder made of oxygen-free copper were also impregnated with the U-Alloy 60 to connect. This fabrication method has the advantage of being easier to fabricate than the technique of connecting each tape using indium foil. The energization test results showed that a maximum current value of 16.9 kA was recorded at B = 5 T and T = 30 K, however, a burnout occurred in the current feeder before the critical current was determined. Then, the improved WISE conductor has been designed and tested which showed a maximum of 19kA was reached in the self-field and 20K. However, burnout still occurred in the current feeder section. In those experiments, the superconducting section has not been damaged at all. If this burnout had been avoided, a higher current-carrying capacity could have been obtained. Identifying the cause of burnout and improving the current feeder is required.