Zeitschriftenartikel: „Electric discharges – Computer simulation“

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Rodríguez-Serna, Johnatan M., Ricardo Albarracín-Sánchez, Ming Dong und Ming Ren. „Computer Simulation of Partial Discharges in Voids inside Epoxy Resins Using Three-Capacitance and Analytical Models“. Polymers 12, Nr. 1 (02.01.2020): 77. http://dx.doi.org/10.3390/polym12010077.

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Epoxy resin is one of the most common polymers used as part of the insulation system in key electrical assets such as power transformers and hydrogenerators. Thus, it is necessary to know their main characteristics and to evaluate their condition when subjected to High Voltage (HV). A brief review of epoxy resins’ applications as insulating materials is made, their main characteristics as insulating media are given, the improvements with nano-fillers are summarized and the main electric properties required for Partial Discharges (PD) modelling are listed. In addition, the theoretical background and state-of-the-art of the three-capacitance and analytical models for simulating PD in solid dielectrics, such as epoxy resins, are reviewed in detail. Besides, their main advantages and disadvantages are presented, some critical arguments to the modelling procedure and assumptions are made and some improvements are proposed, taking into account conclusions made from other authors using models related to the PD development process. Finally, a case study was simulated using a modified three-capacitance model and the analytical model. The PD rate, q-φ-n diagrams and the minimum, mean and maximum PD electric charge are compared with measurements reported in the literature. Simulation results are in reasonable agreement with measured values. Capacitance models can be implemented in general purpose electric circuit simulation packages; however, its simulation is computationally expensive. Additional to this, although the modified three-capacitance model is not as accurate as finite elements or analytical models, results are also in agreement with real data.

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Rocha, Gabriel Vianna Soares, Raphael Pablo de Souza Barradas, João Rodrigo Silva Muniz, Ubiratan Holanda Bezerra, Igor Meireles de Araújo, Daniel de Souza Avelar da Costa, Abner Cardoso da Silva, Marcus Vinícius Alves Nunes und Jucileno Silva e. Silva. „Optimized Surge Arrester Allocation Based on Genetic Algorithm and ATP Simulation in Electric Distribution Systems“. Energies 12, Nr. 21 (28.10.2019): 4110. http://dx.doi.org/10.3390/en12214110.

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The efficient protection of electric power distribution networks against lightning discharges is a crucial problem for distribution electric utilities. To solve this problem, the great challenge is to find a solution for the installation of surge arresters at specific points in the electrical grid and in a sufficient quantity that can ensure an adequate level of equipment protection and be within the utility’s budget. As a solution to this problem of using ATP (Alternative Transient Program), this paper presents a methodology for optimized surge arrester allocation based on genetic algorithm (GA), with a fitness function that maximizes the number of protected equipment according to the financial availability for investment in surge arresters. As ATP may demand too much processing time when running large distribution grids, an innovative procedure is implemented to obtain an overvoltage severity description of the grid and select only the most critical electric nodes for the incidence of lightning discharges, in the GA allocation procedure. The results obtained for the IEEE-123 bus electric feeder indicate a great reduction of flashover occurrence, thus increasing the equipment protection level.

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Barradas, Raphael Pablo de Souza, Gabriel Vianna Soares Rocha, João Rodrigo Silva Muniz, Ubiratan Holanda Bezerra, Marcus Vinícius Alves Nunes und Jucileno Silva e. Silva. „Methodology for Analysis of Electric Distribution Network Criticality Due to Direct Lightning Discharges“. Energies 13, Nr. 7 (01.04.2020): 1580. http://dx.doi.org/10.3390/en13071580.

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Direct lightning discharges in overhead distribution networks invariably cause serious insulation damage, frequently leading to the electric system’s partial or total shutdown. Installing lightning arresters can be very effective, and it is commonly used to minimize this problem; however, considering that typically, electric distribution grids exhibit a very large number of electrical nodes, the massive use of lightning arresters may not be economically viable. In this way, this article proposes a methodology for allocating lightning arresters that can significantly reduce the number of lightning arresters installed, but at the same time maintaining an adequate protection level for the distribution grid. The proposed methodology, named Direct Discharge Crossing (DDC), analyzes the network criticality based on two main factors, which are the overvoltage magnitudes and the number of flashovers provoked by lightning discharges, and defines a feeder lightning performance function that is used to indicate the recommended location for lightning arresters’ installation. The simulation studies are accomplished using the IEEE 34 bus distribution grid and ATP software to demonstrate the efficacy of the proposed solution, which is confirmed by the results presented.

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SETTAOUTI, A., und L. SETTAOUTI. „NUMERICAL SIMULATION OF THE FORMATION AND PROPAGATION OF STREAMER“. International Journal of Modern Physics C 18, Nr. 06 (Juni 2007): 957–71. http://dx.doi.org/10.1142/s0129183107011066.

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There has been considerable interest in non-thermal discharges over the past decade due to the increased number of industrial applications. The properties of discharges in electronegative gases are most frequently used for technological applications. For the improvement of performance in these applications, it is necessary to understand discharge dynamics experimentally and numerically. In this paper, a Monte Carlo simulation is carried out in sulfur hexafluoride (SF6) in uniform electric fields. The streamer propagation, electron, positive and negative ion distributions and space charge fields are studied in detail as time increases.

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Pu, Ziheng, Chenqu Zhou, Yuyao Xiong, Tian Wu, Guowei Zhao, Baodong Yang und Peng Li. „Two Dimensional Axisymmetric Simulation Analysis of Vegetation Combustion Particles Movement in Flame Gap under DC Voltage“. Energies 12, Nr. 19 (20.09.2019): 3596. http://dx.doi.org/10.3390/en12193596.

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In recent years, extreme high temperature weather occurs frequently, which easily causes forest fires. The forest fire is prone to the trip accident of the transmission line. Previous studies show that charged combustion particles cause electric field distortion in the gap below the transmission line, and trigger discharges near the conductor area. The motion and distribution characteristics of combustion particles in the gap have an important influence on the discharge characteristics. Therefore, the size and morphology of combustion particles are analyzed through combustion experiments with typical vegetation. The combustion particles are mainly affected by the air drag force, electric field force and gravity. The interaction and influence of temperature, fluid, electric field and the multi-physical field of particle motion are comprehensively analyzed. A two dimensional (2D) axisymmetric simulation model is established by simplifying the flame region. According to the heat release rate of vegetation flame combustion, the fluid temperature and velocity are calculated. Combined with the fluid field and electric field, the forces on particles and movement are calculated. The results can provide a basis for the analysis of the electric field distortion, and further study the discharge mechanism of the gap under the condition of vegetation flame.

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Skiba, Andrzej J. „Simulation of Atmospheric Discharge at Power Line“. AUTOMATYKA, ELEKTRYKA, ZAKLOCENIA 11 (30.09.2020): 8–14. http://dx.doi.org/10.17274/aez.2020.41.01.

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Modelling electrical circuits by application of schemes containing elements with distributed parameters such as transmission lines has been applied in this research. Functions approximating voltage or current atmospheric discharges have been presented together with frequency spectra of these functions. The results of computer simulations obtained with the help of PSpice software have been presented for a simplified three-phase circuit subject to such discharge.

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He, He und Cui. „Charge-Simulation-Based Electric Field Analysis and Electrical Tree Propagation Model with Defects in 10 kV XLPE Cable Joint“. Energies 12, Nr. 23 (27.11.2019): 4519. http://dx.doi.org/10.3390/en12234519.

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The most severe partial discharges and main insulation failures of 10 kV cross-linked polyethylene cables occur at the joint due to defects caused by various factors during the manufacturing and installation processes. The electric field distortion is analyzed as the indicator by the charge simulation method to identify four typical defects (air void, water film, metal debris, and metal needle). This charge simulation method is combined with random walk theory to describe the stochastic process of electrical tree growth around the defects with an analysis of the charge accumulation process. The results illustrate that the electrical trees around the metal debris and needle are more likely to approach the cable core and cause main insulation failure compared with other types of the defects because the vertical field vector to the cable core is significantly larger than the field vectors to other directions during the tree propagation process with conductive defects. The electric field was measured around the cable joint surface and compared with the simulation results to validate the calculation model and the measurement method. The air void and water film defects are difficult to detect when their sizes are less than 5 mm3 because the field distortions caused by the air void and water film are relatively small and might be concealed by interference. The proposed electric field analysis focuses on the electric field distortion in the cable joint, which is the original cause of the insulation material breakdown. This method identifies the defect and predicts the electrical tree growth in the cable joint simultaneously. It requires no directly attached or embedded sensors to impact the cable joint structure and maintains the power transmission during the detection process.

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He, Miao, Miao Hao, George Chen, Xin Chen, Wenpeng Li, Chong Zhang, Haitian Wang, Mingyu Zhou und Xianzhang Lei. „Numerical modelling on partial discharge in HVDC XLPE cable“. COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, Nr. 2 (05.03.2018): 986–99. http://dx.doi.org/10.1108/compel-07-2017-0297.

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PurposeHigh voltage direct current (HVDC) cable is an important part in the electric power transmission and distribution systems. However, very little research has been carried out on partial discharge under direct current (DC) conditions. Niemeyer’s model has been widely used under alternating current (AC) conditions. This paper aims to intend to modify the Niemeyer’s model considering both electric field and charge dynamics under DC conditions, and therefore proposes a numerical model describing partial discharge characteristics in HVDC cable. Design/methodology/approachThis paper intends to understand partial discharge characteristics under DC conditions through numerical modelling. Niemeyer’s model that has been widely used under AC conditions has been modified, taking both electric field and charge dynamics under DC conditions into consideration. The effects of loading level or current through the conductor, cavity location and material properties on partial discharges have also been studied. FindingsElectrical conductivity is important in determining the characteristics of partial discharge under DC conditions and discharges tend to happen in short when the cavity field exceeds the inception level under the parameter values studied in the paper. Research limitations/implicationsBuilding the numerical model is the purpose of the paper, and there is lack in experiment and the comparison between the simulation results and experiment. Practical implicationsThe proposed model provides the numerical model describing partial discharge in HVDC cable and helps understand the partial discharge mechanism under DC voltage. Originality/valueTo the best of the author’s knowledge, this paper is a very early research on the numerical modelling work on partial discharge under DC voltage.

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Fujiwara, T., T. Shimada und K. Sugita. „Computer simulation of discharge development under an induced toroidal electric field“. Journal of Physics D: Applied Physics 18, Nr. 6 (14.06.1985): 1101–11. http://dx.doi.org/10.1088/0022-3727/18/6/013.

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Andrade, Arthur F., Edson G. Costa, Filipe L. M. Andrade, Clarice S. H. Soares und George R. S. Lira. „Design of Cable Termination for AC Breakdown Voltage Tests“. Energies 12, Nr. 16 (09.08.2019): 3075. http://dx.doi.org/10.3390/en12163075.

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International standards prescribe overvoltage tests to evaluate the insulating material performance of high-voltage cables. However, it is difficult to manage the electric fields at the cable ends when laboratory measurements are carried out because surface and external discharges occur at the cable termination. Therefore, this paper presents a procedure for designing cable terminations to reduce the electric field at the cable ends to appropriate levels even in the case of overvoltage tests. For this purpose, computer simulations of electric field distribution using the finite element method (FEM) were performed. A 35 kV cable model was employed as a sample. An voltage with RMS (root mean square) value of 300 kV was used as an overestimate of breakdown voltage for the internal insulating material. The cable termination model obtained through the proposed methodology allows an electric field reduction in air, preventing the occurrence of external discharges, and thus permitting the breakdown voltage measurement of the cable’s inner insulation.

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Liu, Yunpeng, Shuo Jiang, Zheng Zhong, Jianghai Geng und Fangcheng Lv. „Alternating Current Discharge Characteristics and Simulation Analysis of Rod-Plane Short Air Gaps under Salt Fog Conditions“. Energies 11, Nr. 9 (27.08.2018): 2251. http://dx.doi.org/10.3390/en11092251.

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In this paper, smog meteorological conditions in the natural environment is simulated by the salt fog method. The study of the alternating current (AC) discharge characteristics of rod-plane short air gaps in salt fog environments has important guiding significance for how to strengthen the external insulation strength of ultra-high voltage (UHV) transmission lines and electrical equipment in smog environments. The rod-plane short air gap is selected as the model to simulate the extremely uneven electric field. The AC discharge test is carried out in the salt fog environment with different conductivity, and the finite element method (FEM) is used to simulate the distribution of electric field in air gap under salt fog environment conditions. The results show that under clean fog conditions the AC discharge voltage in the air gap increased by 15.1% to 35.5% compared to that under dry conditions. With the increased conductivity of salt fog, the AC discharge voltage in air gap decreased by 4.1% to 9.2% compared to that under clean fog conditions, and the reduction is within 10%. The distortion of the electric field and the adsorption of free electrons in the gap by droplets lead to the decrease of the electric field intensity in the air gap. With the increase of the conductivity, the electric field intensity in the air gap increases slightly. Meanwhile, the influence of salt fog and its conductivity on the AC discharge voltage of rod-plane short air gap is examined, becoming saturated with the increase of the gap distance and the conductivity of salt fog.

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Guo, Z. N., T. M. Yue, T. C. Lee und W. S. Lau. „Computer simulation and characteristic analysis of electrode fluctuation in wire electric discharge machining“. Journal of Materials Processing Technology 142, Nr. 2 (November 2003): 576–81. http://dx.doi.org/10.1016/s0924-0136(03)00662-9.

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Florkowski, Marek, Barbara Florkowska und Pawel Zydron. „Partial Discharges in Insulating Systems of Low Voltage Electric Motors Fed by Power Electronics—Twisted-Pair Samples Evaluation“. Energies 12, Nr. 5 (26.02.2019): 768. http://dx.doi.org/10.3390/en12050768.

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Power electronics switching devices currently represent the dominant technology for supplying low voltage (LV) electric motors. The fast switching processes exert a different class of stress on dielectric insulating materials than standard sinusoidal excitations. Such stresses result in an increase in the dynamic activity of the working electric field, which in turn lead to an increased likelihood of partial discharges (PD). The stator design of low voltage motor is often in form of random-wound windings, where the magnet wires (copper or aluminum round wires coated with thin layer of insulation) form a common system of coils with not precisely defined mutual position of particular turns, resulting in various turn-to-turn and coil-to-coil voltage distributions. Pulse Width Modulated (PWM) voltage waveforms from modern electronic inverters are characterized by very short rise times and presence of repetitively occurring overvoltages that can significantly stress the insulation of feeding cables and motors. These factors influence the inception and dynamics of PD and processes of space charge accumulation in electrical insulation. In this paper investigations performed on round magnet wire twisted-pair samples representing LV motor random-wound winding elements are presented. Special attention was afforded to the twist configurations, observed breakdown voltage and PD activity. To describe the field conditions for the formation of PD in the turn-to-turn insulation system, the results of numerical simulations of electric field distributions for winding wires with different diameters, modeled using the COMSOL program, were analyzed. PD created in the insulating systems of model twisted-pair systems were registered and analyzed using the phase resolved partial discharge analysis (PRPDA) method.

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Wan, Yi Peng, und Wei Yao. „Development of Battery Test System for Electric Vehicle“. Applied Mechanics and Materials 333-335 (Juli 2013): 1699–703. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.1699.

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In order to satisfy the test demand of Electric Vehicle batteries, after the analysis of the existing battery test systems, aiming at the problems of them, an EV battery test platform with high degree of simulation is designed, based on the upper and lower computer structure. The PC software is compiled, which could control the battery to discharge with constant current or constant power, or to simulate the real road status, by the communication with the lower computer through CAN bus and 485 bus. The corresponding control method to realize the discharging test with constant current is designed, also an interface to Excel which can read the configure information from Excel to realize the simulation of discharging test is designed. Several battery packs test are completed.

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Li, Zhang, Wu, Cheng und Du. „Particle Simulation Model for Self-Field Magnetoplasmadynamic Thruster“. Energies 12, Nr. 8 (25.04.2019): 1579. http://dx.doi.org/10.3390/en12081579.

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In order to clarify the discharge principle of the self-field magnetoplasmadynamic thruster (MPDT), a two-dimensional axisymmetric particle-in-cell/Monte Carlo collision (PIC/MCC) model is proposed. The spatial distribution and the collision characteristics of discharge plasma were calculated using this model. In addition, the influence of the operation parameters on the plasma was analyzed including the voltage and mass flow rate. The effectiveness of the model was verified by comparison to the experimentally induced magnetic field. It was found that the electrons were mainly accelerated by the electric field in the cathode sheath and the electric field shielding effect of plasma was obvious in the bulk plasma region. Due to the pinch effect, the charged particles were constrained near the cathode. The results of the present work implied that the PIC/MCC model provides an approach to investigate the plasma distribution and a kinetic description of particles for the discharge of the self-field MPDT.

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Petri, Lucas de Paula Santos, Emanuel Antonio Moutinho, Rondinele Pinheiro Silva, Renato Massoni Capelini, Rogério Salustiano, Guilherme Martinez Figueiredo Ferraz, Estácio Tavares Wanderley Neto, Jansen Paula Villibor und Suzana Silva Pinto. „A Portable System for the Evaluation of the Degree of Pollution of Transmission Line Insulators“. Energies 13, Nr. 24 (15.12.2020): 6625. http://dx.doi.org/10.3390/en13246625.

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Surface pollution is a major cause of partial discharges in high voltage insulators in coastal cities, leading to degradation of their surface and accelerating their aging process, which may cause visible arcing, flashovers and system faults. Thus, this work provides a methodology for the assessment of the condition of insulators based on an instrument which generates a severity degree to help the electric utility team schedule maintenance routines for the structures that really need it. The instrument uses a Raspberry Pi board as the processing core, a PicoScope oscilloscope for the data acquisition and an antenna as a partial discharge sensor. The algorithms are implemented in Python, and use artificial intelligence tools, such as a convolutional network and a fuzzy inference system. Laboratory test methods for the simulation of the field pollution conditions were successfully used for the validation of the instrument, which showed a good correlation between the pollution level and the severity degree generated. In addition to that, field collected data were also used for the evaluation of the proposed severity degree, which is demonstrated to be consistent when compared with the utility’s reports and the history of the selected areas from where data were collected.

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Yu, Kaijiang, Xiaozhuo Xu, Qing Liang, Zhiguo Hu, Junqi Yang, Yanan Guo und Hongwei Zhang. „Model Predictive Control for Connected Hybrid Electric Vehicles“. Mathematical Problems in Engineering 2015 (2015): 1–15. http://dx.doi.org/10.1155/2015/318025.

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This paper presents a new model predictive control system for connected hybrid electric vehicles to improve fuel economy. The new features of this study are as follows. First, the battery charge and discharge profile and the driving velocity profile are simultaneously optimized. One is energy management for HEV forPbatt; the other is for the energy consumption minimizing problem of acc control of two vehicles. Second, a system for connected hybrid electric vehicles has been developed considering varying drag coefficients and the road gradients. Third, the fuel model of a typical hybrid electric vehicle is developed using the maps of the engine efficiency characteristics. Fourth, simulations and analysis (under different parameters, i.e., road conditions, vehicle state of charge, etc.) are conducted to verify the effectiveness of the method to achieve higher fuel efficiency. The model predictive control problem is solved using numerical computation method: continuation and generalized minimum residual method. Computer simulation results reveal improvements in fuel economy using the proposed control method.

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Kaloko, Bambang Sri. „LEAD ACID BATTERY MODELING FOR ELECTRIC CAR POWER SOURCES“. Indonesian Journal of Chemistry 9, Nr. 3 (24.06.2010): 414–19. http://dx.doi.org/10.22146/ijc.21508.

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Successful commercialization of electric vehicles will require a confluence of technology, market, economic, and political factors that transform EVs into an attractive choice for consumers. The characteristics of the traction battery will play a critical role in this transformation. The relationship between battery characteristics such as power, capacity and efficiency, and EV customer satisfaction are discussed based on real world experience. A general problem, however, is that electrical energy can hardly be stored. In general, the storage of electrical energy requires its conversion into another form of energy. Electrical energy is typically obtained through conversion of chemical energy stored in devices such as batteries. In batteries the energy of chemical compounds acts as storage medium, and during discharge, a chemical process occurs that generates energy which can be drawn from the battery in form of an electric current at a certain voltage. A computer simulation is developed to examine overall battery design with the MATLAB/Simulink. Battery modelling with this program have error level less than 5%. Keywords: Electrochemistry, lead acid battery, stored energy

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Wan, Yi Peng, und Wei Yao. „Study on Mechanical Automation with Improvement of Battery Test System for Electric Vehicle“. Advanced Materials Research 738 (August 2013): 287–91. http://dx.doi.org/10.4028/www.scientific.net/amr.738.287.

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Aiming at the problems of the existing battery test system, a EV battery test platform with high degree of simulation is designed, based on the upper and lower computer structure after a lot of analysis. The PC software is also compiled, which could simulate the real road status, or to control the battery to discharge with constant current or constant power, by the communication with the lower computer through 485 bus and CAN bus. The corresponding control method to realize the discharging test with constant current is designed, also an interface to Excel which can read the configure information from Excel to realize the simulation of discharging test is designed. There are some curves I got are shown below. Several battery packs test are completed. Also, the improvement of battery test system for electric vehicle will make a great contribution in the field of mechanical automation

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Chen, R., Z. N. Guo, J. W. Liu, T. M. Yue und S. W. Chen. „A numerical model and computer simulation for machining particle reinforced metal matrix composites in electric discharge machining“. Materials Research Innovations 19, sup1 (April 2015): S1–392—S1–396. http://dx.doi.org/10.1179/1432891715z.0000000001577.

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Li, Jinsong, Hua Yu, Min Jiang, Hong Liu und Guanliang Li. „Numerical Modeling of Space–Time Characteristics of Plasma Initialization in a Secondary Arc“. Energies 12, Nr. 11 (03.06.2019): 2128. http://dx.doi.org/10.3390/en12112128.

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A numerical model based on the finite element simulation software COMSOL was developed to investigate the secondary arc that can limit the success of single-phase auto-reclosure solutions to the single-phase-to-ground fault. Partial differential equations accounting for variation of densities of charge particles (electrons, positive and negative ions) were coupled with Poisson’s equation to consider the effects of space and surface charges on the electric field. An experiment platform was established to verify the numerical model. The brightness distribution of the experimental short-circuit arc was basically consistent with the predicted distribution of electron density, demonstrating that the simulation was effective. Furthermore, the model was used to assess the particle density distribution, electric field variation, and time dependence of ion reactions during the short-circuit discharge. Results showed that the ion concentration was higher than the initial level after the short-circuit discharge, which is an important reason for inducing the subsequent secondary arc. The intensity of the spatial electric field was obviously affected by the high-voltage electrode at the end regions, and the intermediate region was mainly affected by the particle reaction. The time correspondence between the detachment reaction and the ion source generated in the short-circuit discharge process was basically consistent, and the detachment reactions were mainly concentrated in the middle area and near the negative electrode. The research elucidates the relevant plasma process of the secondary arc and will contribute to the suppression of it.

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Li, Chang He, Zhen Lu Han, Lin Gang Li und Guo Yu Liu. „Theoretical and Experimental Investigation into the Surface Roughness of Small-Hole EDM“. Key Engineering Materials 467-469 (Februar 2011): 656–61. http://dx.doi.org/10.4028/www.scientific.net/kem.467-469.656.

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The characteristic physical properties of titanium alloy materials of the electrical discharge machining (EDM) small hole is studied theoretically and experimentally. From the theory of EDM, based on the phenomenon of microcosmic surface on EDM small hole, the model of surface roughness is built, and the regulation between roughness and pulse width, peak electric current was analyzed, and the roughness empiric formula is developed by use of dyadic linear regression method. Furthermore, by computer simulation technology with established formula the results are derived for other people to public data simulation. After being simulated, the results show that the established model in this paper can accurately forecast the value of processing roughness Ra of commonly used in the processing parameters within the framework, provides a useful complement to titanium alloys for processing the theoretical study and practical application.

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SETTAOUTI, A., und L. SETTAOUTI. „MONTE CARLO SIMULATION OF POSITIVE CORONA DISCHARGE IN NITROGEN“. International Journal of Modern Physics C 21, Nr. 07 (Juli 2010): 943–54. http://dx.doi.org/10.1142/s0129183110015609.

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The corona discharge commonly occurs in many engineering devices and processes. Their application is still largely based on empirical knowledge; accordingly it is very important to predict the physical properties of corona discharge by the appropriate numerical method. To control corona discharge properly by understanding of corona discharge properties at different discharge stages, time-varying characteristics of discharge which are resulted from electron collision with the gas molecules should be investigated. A numerical study of a corona discharge in nitrogen in a point to plane geometry is presented. It is obtained by Monte Carlo method and concerns space-time evolution of electron and ion densities as well as electric field distributions along the discharge axis.

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Pelletier, Mathew, John Wanjura, Greg Holt und Paul Funk. „Methods for Protecting a Personal Computer and Data Acquisition Electronics Installed on Mobile Equipment“. AgriEngineering 1, Nr. 1 (16.10.2018): 4–16. http://dx.doi.org/10.3390/agriengineering1010002.

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Successful data acquisition on mobile platforms, such as tractors, requires the provision of protection for the sensitive electronics, as these platforms are inherently rife with electrical transients that have sufficient energy to cause damage to unprotected instrumentation. Unfortunately, though there are many protection options for industrial applications (i.e., those installed at 120VAC), off-the-shelf products for mobile protection are extremely limited and, after a survey, were determined to provide insufficient protection. The objective of this study was to identify the requirements for the protection of mobile platform instrumentation and equipment, and/or identify circuits that can perform this function. A literature review of electrical transients typical to automotive electronics was performed and circuit simulations were performed using open source software. Off-the-shelf circuit components were tested, via simulation, in various configurations until a design emerged that provided adequate protection from all surge classes. To ensure protection of valuable data, one of the design criteria was to ensure the circuit would continue to supply power to the personal computer (PC), and electronics, even during a load-dump event. The circuit was also designed to provide protection from electrical fast transients and electrostatic discharges. The reported circuit is capable of protecting a computer and data acquisition electronics installed on 12 VDC mobile equipment. This simple, inexpensive design meets Automotive Electronics Council requirements and uses readily available components without a specially fabricated circuit board.

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Qu, Lu, Yu Wang, Gang Liu, Minchuan Liao, Hansheng Cai, Tao Zhang, Yeqiang Deng und Xishan Wen. „Simulation Study on Positive Corona Discharge of Receptors on Rotating Wind Turbine Blade Tips under Thundercloud Electric Fields“. Energies 12, Nr. 24 (10.12.2019): 4696. http://dx.doi.org/10.3390/en12244696.

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Recent lightning simulation experiments have not simulated the influence of blade rotation in the long term after corona inception. This study uses a finite element method and considers the adhesion and collision processes of positive ions, aerosol ions, and neutral particles to establish a two-dimensional positive corona discharge model based on a multicomponent diffusion transport equation. The microscopic distribution of these three types of particles and the influence mechanism of charged particles’ migration under electric fields and wind were studied. The results show that ion migration is affected by both electric field and wind speed. The higher the wind speed, the larger is the deviation amplitude of charged particles along the direction of wind. With an increase in wind speed, the corona current on the receptor surface gradually increases. When the wind speed is 30 m/s, the corona current peak value increases by almost six times when compared with that when no wind is present. From this, it can be inferred that blade rotation reduces the concentration of positive ion in the receptor area, thereby facilitating electron avalanche and streamer-leader conversion.

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Wang, Yulong, Xiaohong Zhang, Lili Li, Jinyang Du und Junguo Gao. „Design of Partial Discharge Test Environment for Oil-Filled Submarine Cable Terminals and Ultrasonic Monitoring“. Energies 12, Nr. 24 (14.12.2019): 4774. http://dx.doi.org/10.3390/en12244774.

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Based on the principle of operating an oil-filled-cable operation and the explanation of the oil-filling process provided in the cable operation and maintenance manual of submarine cables, this study investigated oil-pressure variation caused by gas generated as a result of cable faults. First, a set of oil-filled cables and their terminal oil-filled simulation system were designed in the laboratory, and a typical oil-filled-cable fault model was established according to the common faults of oil-filled cables observed in practice. Thereafter, ultrasonic signals of partial discharge (PD) under different fault models were obtained via validation experiments, which were performed by using oil-filled-cable simulation equipment. Subsequently, the ultrasonic signal mechanism was analyzed; these signals were generated via electric, thermal, and acoustic expansion and contraction, along with electric, mechanical, and acoustic electrostriction. Finally, upon processing the 400 experimental data groups, four practical parameters—maximum amplitude of the ultrasonic signal spectrum, Dmax, maximum frequency of the ultrasonic signals, fmax, average ultrasonic signal energy, Dav, and the ultrasonic signal amplitude coefficient, M—were designed to characterize the ultrasonic signals. These parameters can be used for subsequent pattern recognition. Thus, in this study, the terminal PD of an oil-filled marine cable was monitored.

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Zhou, Quan, Mingqian Wen, Taotao Xiong, Tianyan Jiang, Ming Zhou, Xi Ouyang und Lai Xing. „Study on Insulation Breakdown Characteristics of Printed Circuit Board under Continuous Square Impulse Voltage“. Energies 11, Nr. 11 (25.10.2018): 2908. http://dx.doi.org/10.3390/en11112908.

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The widely distributed interconnects in printed circuit boards (PCBs) easily couple with high voltage under the action of electromagnetic pulses, which leads to insulation failure. In this study, the dielectric breakdown characteristics of four typical PCBs are studied under continuous square impulse voltage conditions. First, the electric field distribution in the four electrode models is simulated with the ANSYS software (ANSYS Maxwell 17.0). Electric field simulation results show the weak area of electric field distribution. On this basis, the possible breakdown patterns of PCB are analyzed. Second, the influence of factors, such as temperature, pulse duty ratio, interconnect insulation distance, and air pressure, on PCB breakdown voltage is studied through a breakdown test on the PCBs. Results show that the discharge between the single-layer electrodes of the PCBs is surface discharge, and the breakdown is that of a “gas–solid composite medium”. Meanwhile, the breakdown of a double-layer PCB is solid breakdown. Finally, scanning electron microscopy (SEM) produced by Tescan (Brno, Czech Republic) is performed to study the carbonization channel after PCB breakdown. SEM results reveal that the PCB carbonization channel is influenced by temperature and pressure in varying degrees.

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Krok, Roman. „Influence of work environment on thermal state of electric mine motors“. Archives of Electrical Engineering 60, Nr. 3 (01.09.2011): 357–70. http://dx.doi.org/10.2478/v10171-011-0031-6.

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Influence of work environment on thermal state of electric mine motors The paper presents a model for calculations of the temperature field in electric mine motors with a water cooled frame. That model was worked out with use of modified and improved thermal networks developed by the author for determining the temperature distributions in different types of ac machines. Thermal calculations for a selected type of 400 kW mining motor were performed with use of an original computer program. Their results were compared with those obtained from measurements. On the basis of the verified simulation results there was determined the influence of value changes of parameters characterising the work environment condition (ambient temperature, inlet temperature and cooling water discharge, degree of covering the casing with coal dust) on the mining motor thermal state.

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Yang, Shi-Chun, Hong He, Xiao-Yu Yan, Yu-Hang Chen, Yang Hua, Yao-Guang Cao, Jun Li, Hong-Hai Li und Sheng Yin. „Segmental Track Analysis in Dynamic Wireless Power Transfer“. Energies 12, Nr. 20 (14.10.2019): 3875. http://dx.doi.org/10.3390/en12203875.

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Electric vehicles have gained more and more attention because of the serious oil crisis and environmental problems. However, the disadvantages of the electric vehicle, such as short driving range, high battery cost, and inconvenient charging, are hindering its market development and expansion. The realization of on-road wireless power transfer technology can effectively solve the problems of short driving range, prevent the battery from being completely discharged to prolong its service life, and reduce requirement of on-board battery. In this paper, the charging mode and the compensation topology of wireless power transfer technology are discussed and then the equivalent circuit model of segmental wireless power transfer system is built. We carried out some magnetic field simulation to analyze how the track shape and length influence coupling coefficient, which is later verified by experiments.

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Michalczuk, M., L. M. Grzesiak und B. Ufnalski. „Hybridization of the lithium energy storage for an urban electric vehicle“. Bulletin of the Polish Academy of Sciences: Technical Sciences 61, Nr. 2 (01.06.2013): 325–33. http://dx.doi.org/10.2478/bpasts-2013-0030.

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Abstract This paper discusses benefits of introducing an ultracapacitor (UC) bank into a battery electric vehicle (BEV) powertrain. The case of 12kWh LiFePO4 battery pack is studied quantitatively. Simulation results refer, inter alia, to three main scenarios: fresh cells, half-used battery cells, and half-used ultracapacitors and batteries. Thermal modeling is incorporated into the simulation. Data from real world are considered: various driving cycles recorded using GPS receiver (incl. elevation), discharge curves from battery manufacturer, and UC equivalent series resistance (ESR) variations due to cycling according to real data reported in papers. Cost, as well as gravimetric and volumetric issues are presented. The key decisions referring to an energy storage for BEV being currently designed within the frame of ECO-Mobility Project are highlighted.

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Oliveira, Janaína G., Johan Lundin und Hans Bernhoff. „Power Balance Control in an AC/DC/AC Converter for Regenerative Braking in a Two-Voltage-Level Flywheel-Based Driveline“. International Journal of Vehicular Technology 2011 (03.11.2011): 1–9. http://dx.doi.org/10.1155/2011/934023.

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The integration of a flywheel as a power handling can increase the energy storage capacity and reduce the number of battery charge/discharge cycles. Furthermore, the ability of recovering energy of the vehicle during breaking can increase the system efficiency. The flywheel-based all-electric driveline investigated here has its novelty in the use of a double-wound flywheel motor/generator, which divides the system in two different voltage levels, enhancing the efficiency of the electric driveline. The connection of two AC electrical machines (i.e., the flywheel and the wheel motor) with different and variable operation frequency is challenging. A power matching control applied to an AC/DC/AC converter has been implemented. The AC/DC/AC converter regenerates the electric power converted during braking to the flywheel machine, used here as power handling device. By controlling the power balance, the same hardware can be used for acceleration and braking, providing the reduction of harmonics and robust response. A simulation of the complete system during braking mode has been performed both in Matlab and Simulink, and their results have been compared. The functionality of the proposed control has been shown and discussed, with full regeneration achieved. A round-trip efficiency (wheel to wheel) higher than 80% has been obtained.

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Alvarez-Diazcomas, Alfredo, Adyr A. Estévez-Bén, Juvenal Rodríguez-Reséndiz, Miguel-Angel Martínez-Prado und Jorge D. Mendiola-Santíbañez. „A Novel RC-Based Architecture for Cell Equalization in Electric Vehicles“. Energies 13, Nr. 9 (08.05.2020): 2349. http://dx.doi.org/10.3390/en13092349.

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Nowadays, research on electric vehicles is increasing because they have the potential to decrease greenhouse-gas emissions dramatically in the transport sector. For these types of vehicles, the battery is one of the main components. The traction system needs a cell series connection to fulfill the energy requirements. Nevertheless, batteries differ from each other due to a normal dispersion in their capacity, internal resistance, and self-discharge rate. This paper presents a novel battery equalizer circuit using an RC-based topology to equalize two adjacent cells of a battery pack. It has the advantage of merging a resistor-based equalizer, a capacitor-based equalizer, and an RC-based equalizer in one circuit. In this way, it is possible to limit the current stress in the components of the circuit. The proposed method increases the equalization time by 35% for a threshold current of 4 A. However, it is possible design the system for another threshold current. Finally, the complexity of the controller is not compromised in the proposed architecture. The operation, analysis, and design of the architecture are presented and compared to the classic schemes. The theoretical analysis is validated through simulation results.

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Giorgi, Maria Grazia De, Antonio Ficarella, Donato Fontanarosa, Elisa Pescini und Antonio Suma. „Investigation of the Effects of Plasma Discharges on Methane Decomposition for Combustion Enhancement of a Lean Flame“. Energies 13, Nr. 6 (20.03.2020): 1452. http://dx.doi.org/10.3390/en13061452.

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The present work focuses on the impact of dielectric barrier discharge (DBD) plasma actuators (PAs) on non-premixed lifted flame stabilization in a methane CH4-air Bunsen burner. Two coaxial DBD-PA configurations are considered. They are composed of a copper corona, installed on the outer surface of a quartz tube and powered with a high voltage sinusoidal signal, and a grounded needle installed along the burner axis. The two configurations differ in the standoff distance value, which indicates the positioning of the high frequency/high voltage (HV) electrode’s upper edge with respect to the needle tip. Experimental results highlight that flame reattachment is obtained at a lower dissipated power when using a negative standoff distance (i.e., placing the needle upstream with respect to the corona). At 11 kV peak-to-peak voltage and 20 kHz frequency, plasma actuation allowed for reattaching the flame with a very low dissipated power (of about 0.05 W). Numerical simulations of the electrostatic field confirmed that this negative standoff configuration has a beneficial effect on the momentum sources, which oppose the flow and show that the highest electric field extends into the inner quartz tube, as confirmed by experimental visualization close to the needle tip. The modeling predicted an increase in the gas temperature of about 21.8 °C and a slight modification of the fuel composition at the burner exit. This impacts the flame speed with a 10% increase close to the stoichiometric conditions with respect to the clean configuration.

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Lysov, Nikolay, Alexander Temnikov, Leonid Chernensky, Alexander Orlov, Olga Belova, Tatiana Kivshar, Dmitry Kovalev und Vadim Voevodin. „Physical Simulation of the Spectrum of Possible Electromagnetic Effects of Upward Streamer Discharges on Model Elements of Transmission Line Monitoring Systems Using Artificial Thunderstorm Cell“. Applied Sciences 11, Nr. 18 (18.09.2021): 8723. http://dx.doi.org/10.3390/app11188723.

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The results of a physical simulation using negatively charged artificial thunderstorm cells to test the spectrum of possible electromagnetic effects of upward streamer discharges on the model elements of transmission line monitoring systems (sensor or antennas) are presented. Rod and elongated model elements with different electric field amplification coefficients are investigated. A generalization is made about the parameters of upward streamer current impulse and its electromagnetic effect on both kinds of model elements. A wavelet analysis of the upward streamer corona current impulse and of the signal simultaneously induced in the neighboring model element is conducted. A generalization of the spectral characteristics of the upward streamer current and of the signals induced by the electromagnetic radiation of the nearby impulse streamer corona on model elements is made. The reasons for super-high and ultra-high frequency ranges in the wavelet spectrum of the induced electromagnetic effect are discussed. The characteristic spectral ranges of the possible electromagnetic effect of upward streamer flash on the elements of transmission line monitoring systems are considered.

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Martinson, Emil, und Jerker Delsing. „Electric spark discharge as an ultrasonic generator in flow measurement situations“. Flow Measurement and Instrumentation 21, Nr. 3 (September 2010): 394–401. http://dx.doi.org/10.1016/j.flowmeasinst.2010.04.011.

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Kumar, Ravinder, Ankita Kumar und Inderdeep Singh. „Electric discharge drilling of micro holes in CFRP laminates“. Journal of Materials Processing Technology 259 (September 2018): 150–58. http://dx.doi.org/10.1016/j.jmatprotec.2018.04.031.

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37

Rashidizadeh-Kermani, Homa, Hamid Najafi, Amjad Anvari-Moghaddam und Josep Guerrero. „Optimal Decision-Making Strategy of an Electric Vehicle Aggregator in Short-Term Electricity Markets“. Energies 11, Nr. 9 (12.09.2018): 2413. http://dx.doi.org/10.3390/en11092413.

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This paper proposes the problem of decision making of an electric vehicle (EV) aggregator in a competitive market in the presence of different uncertain resources. In the proposed model, a bi-level problem is formulated where, in the upper-level, the objective of the aggregator is to maximize its expected profit through its interactions and, in the lower-level, the EV owners minimize their payments. Therefore, the objectives of the upper and the lower-level are contrary. To solve the obtained nonlinear bi-level program, Karush-Kuhn-Tucker (KKT) optimality conditions and strong duality are applied to transform the initial problem into a linear single-level problem. Moreover, to deal with various uncertainties, including market prices, EVs charge/discharge demands and the prices offered by rivals, a risk measurement tool is incorporated into the problem. The proposed model is finally applied to a test system and its effectiveness is evaluated. Simulation results show that the proposed approach has the potential to offer significant benefits to the aggregator and EV owners for better decision-making in an uncertain environment. During different situations, it is observed that with increasing risk-aversion factor, as the aggregator tries to hedge against volatilities, its purchases from day-ahead and negative balancing markets decreases significantly. However, the participation of EV aggregator in the positive balancing market increases accordingly to make more profit.

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Guan, Jen-Chiun, Bo-Chiuan Chen und Yuh-Yih Wu. „Design of an Adaptive Power Management Strategy for Range Extended Electric Vehicles“. Energies 12, Nr. 9 (28.04.2019): 1610. http://dx.doi.org/10.3390/en12091610.

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The cruising distance of the range extended electric vehicle (REEV) can be further extended using a range extender, which consists of an engine and a generator, i.e., a genset. An adaptive power management strategy (PMS) based on the equivalent fuel consumption minimization strategy (ECMS) is proposed for the REEV in this paper. The desired trajectory of the state of charge (SOC) is designed based on the energy-to-distance ratio, which is defined as the difference between the initial SOC and the minimum allowable SOC divided by the remaining travel distance, for discharging the battery. A self-organizing fuzzy controller (SOFC) with SOC feedback is utilized to modify the equivalence factor, which is defined as the fuel consumption rate per unit of electric power, for tracking the desired SOC trajectory. An instantaneous cost function, that consists of the fuel consumption rate of the genset and the equivalent fuel consumption rate of the battery, is minimized to find the optimum power distribution for the genset and the battery. Dynamic programming, which is a global minimization method, is employed to obtain the performance upper bound for the target REEV. Simulation results show that the proposed algorithm is adaptive for different driving cycles and can effectively increase the fuel economy of the thermostat control strategy (TCS) by 11.1% to 16%. The proposed algorithm can also reduce average charging/discharging powers and low SOC operations for possibly extending the battery life and increasing the battery efficiency, respectively. An experiment of the prototype REEV on a chassis dynamometer is set up with the proposed algorithm implemented on a real-time controller. Experiment results show that the proposed algorithm can increase the fuel economy of the TCS by 7.8% for the tested driving cycle. In addition, the proposed algorithm can reduce the average charge/discharge powers of TCS by 7.9% and 11.7%, respectively.

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Liu, Yingpei, Yan Li, Haiping Liang, Jia He und Hanyang Cui. „Energy Routing Control Strategy for Integrated Microgrids Including Photovoltaic, Battery-Energy Storage and Electric Vehicles“. Energies 12, Nr. 2 (18.01.2019): 302. http://dx.doi.org/10.3390/en12020302.

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The Energy Internet is an inevitable trend of the development of electric power system in the future. With the development of microgrids and distributed generation (DG), the structure and operation mode of power systems are gradually changing. Energy routers are considered as key technology equipment for the development of the Energy Internet. This paper mainly studies the control of the LAN-level energy router, and discusses the structure and components of the energy router. For better control of the power transmission of an energy router, the energy routing control strategy for an integrated microgrid, including photovoltaic (PV) energy, battery-energy storage and electric vehicles (EVs) is studied. The front stage DC/DC converter of the PV system uses maximum power point tracking (MPPT) control. The constant current control is used by the bidirectional DC/DC converter of the battery-energy storage system and the EV system when they discharge. The DC/AC inverters adopt constant reactive power and constant DC voltage control. Constant current constant voltage control is adopted when an EV is charged. The control strategy model is simulated by Simulink, and the simulation results verify the feasibility and effectiveness of the proposed control strategy. The DG could generate reactive power according to the system instructions and ensure the stable output of the DC voltage of the energy router.

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Panchal, Satyam, Krishna Gudlanarva, Manh-Kien Tran, Roydon Fraser und Michael Fowler. „High Reynold’s Number Turbulent Model for Micro-Channel Cold Plate Using Reverse Engineering Approach for Water-Cooled Battery in Electric Vehicles“. Energies 13, Nr. 7 (02.04.2020): 1638. http://dx.doi.org/10.3390/en13071638.

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The investigation and improvement of the cooling process of lithium-ion batteries (LIBs) used in battery electric vehicles (BEVs) and hybrid electric vehicles (HEVs) are required in order to achieve better performance and longer lifespan. In this manuscript, the temperature and velocity profiles of cooling plates used to cool down the large prismatic Graphite/LiFePO4 battery are presented using both laboratory testing and modeling techniques. Computed tomography (CT) scanning was utilized for the cooling plate, Detroit Engineering Products (DEP) MeshWorks 8.0 was used for meshing of the cooling plate, and STAR CCM+ was used for simulation. The numerical investigation was conducted for higher C-rates of 3C and 4C with different ambient temperatures. For the experimental work, three heat flux sensors were attached to the battery surface. Water was used as a coolant inside the cooling plate to cool down the battery. The mass flow rate at each channel was 0.000277677 kg/s. The k-ε model was then utilized to simulate the turbulent behaviour of the fluid in the cooling plate, and the thermal behaviour under constant current (CC) discharge was studied and validated with the experimental data. This study provides insight into thermal and flow characteristics of the coolant inside a cooing plate, which can be used for designing more efficient cooling plates.

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Lai, Ching-Ming, Jiashen Teh, Yuan-Chih Lin und Yitao Liu. „Study of a Bidirectional Power Converter Integrated with Battery/Ultracapacitor Dual-Energy Storage“. Energies 13, Nr. 5 (06.03.2020): 1234. http://dx.doi.org/10.3390/en13051234.

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A patented bidirectional power converter was studied as an interface to connect the DC-bus of driving inverter, battery energy storage (BES), and ultracapacitor (UC) to solve the problem that the driving motor damages the battery life during acceleration and deceleration in electric vehicles (EVs). The proposed concept was to adopt a multiport switch to control the power flow and achieve the different operating mode transitions for the better utilization of energy. In addition, in order to improve the conversion efficiency, the proposed converter used a coupled inductor and interleaved-pulse-width-modulation (IPWM) control to achieve a high voltage conversion ratio (i.e., bidirectional high step-up/down conversion characteristics). This study discussed the steady-state operation and characteristic analysis of the proposed converter. Finally, a 500 W power converter prototype with specifications of 72 V DC-bus, 24 V BES, and 48 V UC was built, and the feasibility was verified by simulation and experiment results. The highest efficiency points of the realized prototype were 97.4%, 95.5%, 97.2%, 97.1%, and 95.3% for the UC charge, battery charge, UC discharge, the dual-energy in series discharge, and battery discharge modes, respectively.

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Baboraik, Abdulrahman, und Alexander Usachev. „New model of explanation for phase angle pattern of online partial discharge measurement in winding insulation of turbine generator“. Journal of Electrical Engineering 72, Nr. 1 (01.02.2021): 66–77. http://dx.doi.org/10.2478/jee-2021-0010.

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Abstract On-line partial discharge (PD) measurement in electrical insulation of the turbine generator (TG) is an essential approach to control the quality of insulation and to avoid any undesired shutdowns of TG. Although in the last few decades the number of research in PD on-line monitoring methods in the stator winding of TG has increased significantly, it is still not clear yet why PD only appears at certain phase angles of the AC cycle in the phase resolved partial discharge (PRPD) pattern. Moreover, there is not yet any clarification on how the winding configuration of stator may affect PD phase angle pattern. For this reason, this work examines detailed study of the impact of the winding diagram on PD occurrence in the stator winding of real turbine generator class TVF-60-2 (60 MW, 10.5 KV). In addition, a computer simulation of various sizes of ellipsoidal cavities from 0.1 to 2.5 mm between conductor bar and stator core were carried out by using Laplaces equation in Finite Element Analysis (FEA) software ComSol to investigate the relation between the cavity size and coefficient of electric field. As a result of that, the phase angle of PD occurrence in the stator winding will highly depend on the configuration of bars connection, and the computer simulation has helped identifying the PD inception voltage and applied voltage of various ellipsoidal defects size. These two results have helped proposing an initial new theoretical model of explanation the relationship between voltage distributions and phase angle of PD occurrence to determine the degradation level of insulation caused by ellipsoidal defects in the insulation bars of the stator winding which can be used for stator windings of TG rated 6 kV and higher. This model is the initial step to develop a further comprehensive model of explanation for PRPD patterns which will consider all other types of defects as well as the space charge effects from the previous PD.

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Mehta, Dhruvesh, Prasanta Kundu und Anandita Chowdhury. „Development of energy efficient, cost-optimized transformer with low partial discharges“. Modelling, Measurement and Control A 91, Nr. 2 (30.06.2018): 59–65. http://dx.doi.org/10.18280/mmc_a.910205.

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Campagna, Nicola, Vincenzo Castiglia, Rosario Miceli, Rosa Anna Mastromauro, Ciro Spataro, Marco Trapanese und Fabio Viola. „Battery Models for Battery Powered Applications: A Comparative Study“. Energies 13, Nr. 16 (06.08.2020): 4085. http://dx.doi.org/10.3390/en13164085.

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Battery models have gained great importance in recent years, thanks to the increasingly massive penetration of electric vehicles in the transport market. Accurate battery models are needed to evaluate battery performances and design an efficient battery management system. Different modeling approaches are available in literature, each one with its own advantages and disadvantages. In general, more complex models give accurate results, at the cost of higher computational efforts and time-consuming and costly laboratory testing for parametrization. For these reasons, for early stage evaluation and design of battery management systems, models with simple parameter identification procedures are the most appropriate and feasible solutions. In this article, three different battery modeling approaches are considered, and their parameters’ identification are described. Two of the chosen models require no laboratory tests for parametrization, and most of the information are derived from the manufacturer’s datasheet, while the last battery model requires some laboratory assessments. The models are then validated at steady state, comparing the simulation results with the datasheet discharge curves, and in transient operation, comparing the simulation results with experimental results. The three modeling and parametrization approaches are systematically applied to the LG 18650HG2 lithium-ion cell, and results are presented, compared and discussed.

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Chen, S. L., und Q. C. Hsu. „Studies on electric-discharge machining of non-contact seal face grooves“. Journal of Materials Processing Technology 140, Nr. 1-3 (September 2003): 363–67. http://dx.doi.org/10.1016/s0924-0136(03)00761-1.

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Zeng, Miaomiao, Peng Zhang, Yang Yang, Changjun Xie und Ying Shi. „SOC and SOH Joint Estimation of the Power Batteries Based on Fuzzy Unscented Kalman Filtering Algorithm“. Energies 12, Nr. 16 (14.08.2019): 3122. http://dx.doi.org/10.3390/en12163122.

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In order to improve the convergence time and stabilization accuracy of the real-time state estimation of the power batteries for electric vehicles, a fuzzy unscented Kalman filtering algorithm (F-UKF) of a new type is proposed in this paper, with an improved second-order resistor-capacitor (RC) equivalent circuit model established and an online parameter identification used by Bayes. Ohmic resistance is treated as a battery state of health (SOH) characteristic parameter, F-UKF algorithms are used for the joint estimation of battery state of charge (SOC) and SOH. The experimental data obtained from the ITS5300-based battery test platform are adopted for the simulation verification under discharge conditions with constant-current pulses and urban dynamometer driving schedule (UDDS) conditions in the MATLAB environment. The experimental results show that the F-UKF algorithm is insensitive to the initial value of the SOC under discharge conditions with constant-current pulses, and the SOC and SOH estimation accuracy under UDDS conditions reaches 1.76% and 1.61%, respectively, with the corresponding convergence time of 120 and 140 s, which proves the superiority of the joint estimation algorithm.

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Rubtsov, N. M., G. I. Tzvetkov und V. I. Chernysh. „The effect of the electric field on the kinetics of dichlorosilane oxidation in the absence of discharge“. Kinetics and Catalysis 41, Nr. 3 (Mai 2000): 307–12. http://dx.doi.org/10.1007/bf02755366.

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Matsugi, K., Y. Wang, T. Hatayama, O. Yanagisawa und K. Syakagohri. „Application of electric discharge process in joining aluminum and stainless steel sheets“. Journal of Materials Processing Technology 135, Nr. 1 (April 2003): 75–82. http://dx.doi.org/10.1016/s0924-0136(02)01040-3.

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Kumar, Ravinder, und Inderdeep Singh. „A modified electrode design for improving process performance of electric discharge drilling“. Journal of Materials Processing Technology 264 (Februar 2019): 211–19. http://dx.doi.org/10.1016/j.jmatprotec.2018.09.014.

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Wang, Tingzhang, Chunya Wu, Henan Liu, Mingjun Chen, Jian Cheng und Su Dingning. „On-machine electric discharge truing of small ball-end fine diamond grinding wheels“. Journal of Materials Processing Technology 277 (März 2020): 116472. http://dx.doi.org/10.1016/j.jmatprotec.2019.116472.

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