2019 International Conference on Electromechanical and Energy Systems (SIELMEN)最新文献

{"title":"Upon the Influence of Charge Image on the Electric Field Intensity","authors":"A. Sălceanu, E. Lunca, B. Alistar, S. Ursache","doi":"10.1109/SIELMEN.2019.8905895","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905895","url":null,"abstract":"The paper is dedicated to studying the contribution of underground image of overhead power lines to the actual electric field strength at a certain point of interest in their immediate vicinity. More precisely, it is about the image of an electric charge; accordingly, an analytical method is developed, allowing as the linear charge density to be calculated based on the effective (r. m. s.) phase voltage and also, the calculation of the electrical potential at the surface of the live conductor. The analytical results were the basis for the validation of some simulations performed with CST Studio and EMFACDC for various power line configurations. An application has been developed to study the influence of soil conductivity and permittivity, the results being compared with the (theoretically) extremes: perfectly conductive and perfect insulator cases. The results showed an increase of about 65% of the electric field strength in wet soil, relative to dry soil. This conclusion is an argument that nuances the rather widespread, superficial approach that, from the point of view of the formation and the influence of electrical charge image in the soil, any soil is a perfect conductor. Finally, a number of achievable recommendations are done, aiming on reducing the exposure to electric fields generated by overhead high-voltage power lines (OhHVPLs).","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122374878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental Pollution Control","authors":"Pascu Mihail Sebastian, C. Romeo, Ursan George-Andrei","doi":"10.1109/SIELMEN.2019.8905843","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905843","url":null,"abstract":"As we know, environmental pollution has become one of the most debated issues of contemporaneity and one of the first order for the management of the company. Man and the environment are inseparable entities, the existence of man being dependent environmental factors, and environmental factors (air, water, soil) can be modified, following their use by humans. Thus it appears pollution, an implicit aspect of life, in the development of which some products result from physiological processes and from human and animal activity, become residues that can disturb living well according to nature and their quantity. With the great scientific advances, their quantity and nature has changed fundamentally. In the last for decades, the process of degradation of environmental factors on our planet has evolved more and more worryingly, the amount of pollutants reaching numbers beyond any imagination. Removing pollution is a problem to correct the errors that cause it.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129486609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SIELMEN 2019 Committees","authors":"","doi":"10.1109/sielmen.2019.8905881","DOIUrl":"https://doi.org/10.1109/sielmen.2019.8905881","url":null,"abstract":"","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123688608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simulation and Measurement of the Radiofrequency Electromagnetic Field Generated by a LTE Base Station","authors":"O. Bejenaru, E. Lunca, V. David","doi":"10.1109/SIELMEN.2019.8905851","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905851","url":null,"abstract":"In this study, the radiofrequency electromagnetic field from a LTE-2600 base station installed in a suburban environment is assessed by both simulations and in-situ measurements. The simulations were performed using EMF-Estimator, a software that implements the methodology described in ITU-T Recommendation K.70 to calculate the cumulative radio frequency exposure levels in the vicinity of transmitting antennas, while the measurements were conducted using a portable N9912A FieldFox spectrum analyzer equipped with a handheld log log-periodic antenna. The simulated and measured electric fields at 18 test points around the LTE base station correlate within acceptable limits, indicating typical RF exposure levels below 2.25% of the exposure limit established by the International Commission on Non-Ionizing Radiation Protection for the general public.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121690594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical Modeling of Unsteady Air Flow with Vortices on Wind Turbine Blades","authors":"V. Radulescu","doi":"10.1109/SIELMEN.2019.8905802","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905802","url":null,"abstract":"Generally, in the classical theory of the wind turbines, at the end of profiles appears an inverse flow of three-dimensional vortices, with significant effects on the turbines efficiency and the lifting coefficient. The turbines distribution in wind parks is essential, due to this wake-effect. In the present paper, this three-dimensional vortex was studied numerically by solving the Navier-Stokes equations, with supplementary corrections imposed by the characteristics of the compressible fluid flow. Supplementary have been analyzed the influence of pressure distribution, blade shape and Reynolds number on the vortices development. A comparison between the numerical and experimental results registered for almost two years was accomplished. The pressure distribution in both cases is in good agreement for blades having as a cross-section, profile NACA 0015. It was used the Navier-Stokes flow solver, associated with a grid with different mesh distribution. The effects of the stream diffusion were neglected for the separated flow, by considering large secondary vortices with the effect of the lift-off. These new considerations will allow a better understanding of vortices formation. Finally, are mentioned some conclusions and references.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128004517","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermal Analysis of Hybrid Tankless Heating System","authors":"G. Pintilie, A. Plesca, D. Lucache","doi":"10.1109/SIELMEN.2019.8905813","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905813","url":null,"abstract":"The paper presents a thermal analysis of the heating system without a hybrid tank, which could be transferred in an extended application regarding the automatic production mode of hot water, from a preset input value to a high output value. This paper describes an automatic hybrid heating system, a miniboiler combined with a tankless heating system, which has the advantage of using a smaller space and thus lower costs. The main purpose is to obtain and maintain a higher temperature of the heated water according to different parameters (inlet temperature, outlet temperature, amperage, time and water flow). Temperatures can be measured in constant or transient mode. The aim is to achieve a faster evolution of the temperature for as long as possible. The method used consists in measuring the inlet-outlet and intermediate temperature by means of K-type thermocouples. Each thermocouple sends a millivolt signal, which can be transmitted via the PLC input analogue to it, and can provide complete data on the behavior of the heating system. he data provided can create the premise to identify the weaknesses of such a system, the actual consumption and subsequently the parametric perfection, to find new material used in the construction of the system and alternative energy sources for the supply of these systems.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"114 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128196519","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of the Operational Method for Calculating the Mode of the Electrical Grid Circuit with Distributed Loads","authors":"V. Dmitrii","doi":"10.1109/SIELMEN.2019.8905864","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905864","url":null,"abstract":"The development of the renewable source component for electricity production leads to an increase in the number of sources connected to the low voltage network and to difficulties in calculating the transient regime. The purpose of this paper is to present a new way of applying the operational method for calculating the regime in circuits with the distributed load, which is not limited by the order of the differential equation and that describes the dynamic processes in the analyzed circuit. As a method of calculating currents in the circuit of a network with tasks and sources of distributed generation, the method of loop currents was selected. The method allows the equations of the voltage balance to be drawn up, so that in each of loop circuit there is only one element of the transverse chains connected in the network power outlets. This ensures that the values of the loop currents with the currents in the respective transverse element coincide, whether we consider the connected load or the distributed source of generation. Knowing the values of currents in the loop of the circuit allows calculation of all derived parameters: voltage drop, loss of power, examination the regime in the natural evolution course in the network, so from the transient regime to the permanent regime. It has been shown that, for the topology of the electrical networks with active-inductive components, the roots of the characteristic equation of the differential equations describing the equilibrium state of the instantaneous voltages in the network circuits can be determined without great difficulties. The analytical solutions allow for calculating the instantaneous values of the loop currents and the voltage drops in the connection nodes of the load and the sources of generation distributed at the low voltage network. The proposed method of applying the operational method is robust both for determining the characteristics of the transient regime at any point of the supply network, and for the parameters of the permanent regime.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134152627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flexible Polynomial Mathematical Model of a Photovoltaic Power Plant","authors":"Chalbash Oleg, Berzan Vladimir","doi":"10.1109/SIELMEN.2019.8905849","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905849","url":null,"abstract":"Solar energy is an important source of clean energy. The purpose of this work is to argue and develop adequate mathematical models that take into account most factors influencing the efficiency of the conversion of the solar energy by photovoltaic power plants. The research methodology is based on a comprehensive analysis of mathematical models of exponential and polynomial form used to describe the current-voltage and volt-watt characteristics characteristics of photovoltaic cells, modules and platforms with PV panels in the mode of electric energy generation. An equation of exponential form is accepted as the basic equation for describing the current – voltage characteristics. A concept and algorithm for formalizing the construction of a mathematical model of a flexible mathematical polynomial model and determining its constant coefficients are proposed. As an approximating function for constructing a polynomial model, the Bernstein polynomial (Bezier function) of the 5th degree is used, using six nodal points. A method for correcting an approximating polynomial has been developed, which consists in changing the coordinates of the selected reference points of the current-voltage curve approximation function when the temperature, insolation and shading of the surfaces of photovoltaics elements change. The accuracy of the approximation of the exponential function by a polynom is estimated. The maximum approximation error does not exceed 1.47%. The feasibility and efficiency of using the polynomial model in calculating the production of electric energy by photovoltaic plants in a given time interval (day, month, year) is shown.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"11 12","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134446800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Computational Aspects Concerned with the Optimized Use of Wavelet Package Trees","authors":"Scărlătescu Lucian Cristian, M. Nicolae, P. Nicolae, I. Nicolae, D. Purcaru","doi":"10.1109/SIELMEN.2019.8905839","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905839","url":null,"abstract":"Decompositions of electric waveforms relying on the Wavelet Package Transform (WPT) provide numerous advantages but requires a significant amount of computational resources (runtime and memory). Previous study of some of the authors were concerned with special properties provided by the weights of energies supplied by odd harmonics in the final nodes of a WPT trees with 5 levels. New researches were made now considering the better sampling rate of modern data acquisition systems. Another topology, with 7 levels, was studied, and interesting results relative to much higher harmonic orders (up to the rank of 256) were obtained with respect to both even and odd harmonic orders. Studies on artificial waveforms polluted with a single harmonic were made firstly, revealing interesting aspects relative to clusters of nodes affected by the same group of harmonic orders. Different pairing patterns of odd and even harmonics were revealed, along with decisions on nodes being more relevant for certain harmonics. Afterward, studies on possible practical application of final nodes sensitivity to limited ranges of harmonic orders were made. The obtained results provide the support for simple computational techniques meant to reduce as much as possible the computational resources required by the WPT analysis.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131077792","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sensorless Predictive Control for PMSM Using MRAS Observer","authors":"M. Nicola, C. Nicola","doi":"10.1109/SIELMEN.2019.8905815","DOIUrl":"https://doi.org/10.1109/SIELMEN.2019.8905815","url":null,"abstract":"This article presents a sensorless MPC (Model Predictive Control) for a PMSM (Permanent Magnet Synchronous Motor) in which the rotor speed is provided by a MRAS (Model Reference Adaptive System) observer, and general control strategy is FOC (Field Oriented Control) type. The results of the numerical simulations show the superiority of the MPC control system compared to the FOC type control system in the case of parameter variation and rapidly varying torque load with a random component. The relatively low complexity of the number of arithmetic operations required to implement the estimation and control algorithms recommends the implementation of an embedded system in real time in future works.","PeriodicalId":129030,"journal":{"name":"2019 International Conference on Electromechanical and Energy Systems (SIELMEN)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133043019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}