ISTET 2013
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Item Power processes quality estimation and compensation for poor quality in low-voltage electric networks(University of West Bohemia, 2013) Zagirnyak, Mykhaylo; Prus, V. V.; Nikitina, A. V.A method of power processes quality estimation and compensation for poor quality in industrial low-voltage electric networks is substantiated. Calculation relations for spectral presentation of power components and quality factors of electric power are improved in accordance with p-q-r-theory of instantaneous power. The structure of compensating device is grounded and a higher efficiency of nonlinear distortions compensation compared with the basic variant of p-q-r-theory is confirmed.
Item Combinatorial method for optimal sizing and placement of active power filters(University of West Bohemia, 2013) Lewandowski, Michał; Walczak, JanuszCombinatorial method for optimal sizing and placement of active power filters (APFs) has been presented in the paper. The main idea is to separate the sizing and placement parts of the algorithm to avoid calling the cost function during the APF sizing part of the algorithm, what allows to overcome some problems associated with nonlinearity and discontinuity of the APF cost function. The results confirm a high effectiveness of the method in comparison with the traditional approach. The main disadvantage of the method is a relatively large amount of computation caused by the combinatorial testing of all possible APF connection nodes.Item Solution of Skin-Effect Problems by means of the Hybrid SDBCI Method(University of West Bohemia, 2013) Aiello, G.; Alfonzetti, S.; Salerno, N.This paper presents a singular version of the hybrid FEM-DBCI method to solve skin effect problems in open boundary domains. This version consists of overlapping the fictitious truncation boundary with the integration one, as in the FEM-BEM method.Item Resistance of thin disks and rings(University of West Bohemia, 2013) Szymanik, Barbara; Gratkowski, StanisławIn this paper the following, classic problem [1] is taken into consideration: calculate the resistance between two, perfectly conducting contacts on the rim of a thin disk (t << a, where a indicates disk’s radius and t is its thickness) of conductivity σ. An example of a simple, approximate solution to above problem can be found in [2], however, it requires contacts to be sufficiently small (i.e. d >> δ, where δ is the contacts’ size and d indicates the distance between them). Our purpose was to find more general solution, valid for contacts of finite size. Moreover, we propose the extension of above problem to thin rings. The exact analytical method of solving the Laplace equation to find the scalar potential was used. Afterwards, the Ohm law to obtain the formulas for disks and rings resistance was utilized. Using the dilogarithm function we obtained simplified, approximate formulas for the disks and rings resistance.Item Behaviour of Ferrofluidic Liquid in Heat Pipe Affected by External Magnetic Field(University of West Bohemia, 2013) Doubek, Jiří; Musálek, Lubomír; Kyncl, Jan; Janiš, Roman; Kuba, JanThe process of transporting magnetic fluid in a heat pipe is modeled. Motion of the fluid is driven by several forces (gravitational force, surface tension, magnetic force and in a small extent also wettability). From the physical viewpoint, the task represents a coupled problem. The paper deals with its continuous mathematical model and its numerical solution. The methodology is illustrated by a typical example.Item Time synchronization in distributed sensor network(University of West Bohemia, 2013) Majchrzycki, Mateusz; Świetlicka, Aleksandra; Gugała, Karol; Karoń, Igor; Kolanowski, Krzysztof; Rybarczyk, AndrzejTime synchronization in a distributed sensor network is a key issue. Data from the sensors are properly synchronized are very good material for further analysis. In the paper a network of medical sensors is presented. It is important to obtain a properly synchronized data from the sensors. This guarantee that the data can be processed to detect correlation between different signals. For the purpose of accurate time synchronization, the simple and efficient algorithm is presented.Item Theoretical Model of Electromagnetic Flowmeter, Verification and Sensitivity Increasing(University of West Bohemia, 2013) Andreev, Andrey; Iatcheva, Ilona; Stancheva, RumenaThe paper deals with the analytical correlation between the obtained polarization voltage and the dielectric fluid velocity through the circular cross section of the polarization transducer. The aim is verification of the analytical results by the comparison of the analytically calculated voltage between the electrodes and its numerically obtained value applying FEM (QuickField 5.6). As the result of the inverse problem solution (Response Surface Methodology, Design of Experiments and Flexible Tolerance Method) the optimal constructive parameters and the exciting magnetic field distribution are determined guarantying maximal outgoing signal and consequently increasing the device sensitivity.Item The shrink-fit using the rotation heating(University of West Bohemia, 2013) Kotlan, Václav; Koudela, LukášHard-coupled model of rotation heating of a ferromagnetic clamping head is presented. The problem is described by three coupled partial differential equations whose coefficients are temperature-dependent functions. The system is solved numerically in the monolithic formulation and results from different software are compared together. The methodology is illustrated by a concrete example which was built and measured. The results are evaluated and discussed.Item Testing of a TSI unit – an electronically controlled engine with a gasoline direct injection system(University of West Bohemia, 2013) Putz, Łukasz; Typańska, DorotaThe article presents a detailed analysis of the TSI (Turbo Straight Injection) gasoline direct injection system used in the vehicles manufactured by Volkswagen Group. The work presents the characteristic construction elements of this type of engine together with the descriptions of their influence on its operation. Next, it presents the results of engine power, torque, pollution emission levels, and fuel consumption tests conducted for the Skoda Superb 1.8 TSI and a comparison of the results with the results obtained for an equivalent engine with indirect fuel injection – Skoda Superb 1.8 T.Item Terahertz inspection of dielectric and composite materials using Synthetic Aperture Focusing Technique(University of West Bohemia, 2013) Lopato, PrzemyslawNondestructive evaluation using terahertz frequency electromagnetic waves is becoming more and more popular. Similar operating principle allows the use of inverse algorithms derived from the ultrasonic technique (UT). In this paper algorithm and results of synthetic aperture focusing technique (SAFT) applied to pulsed terahertz inspection of dielectric and composite objects are presented. The results of both measurements and FDTD simulations are processed by implemented SAFT algorithm.Item Synthesis And Properties Direct Shaping Of An Additive Subset Of Non-Conventional Combined Independent Brushless Exciting Devices For Synchronous Generators(University of West Bohemia, 2013) Plastun, AnatolyAlgorithm of the directed formation of properties of structures for additive subset of independent brushless exciting devices for synchronous generators is considered in the paper. The set of exciting device power part elements is synthesized, allowing to apply nonconventional methods of magnetic and electric combination with the purpose of reduction of expenses for active and constructive materials, as well as labor expenditures for manufacture of the power part of the exciting device. The basic electric circuit of the nonconventionally combined brushless exciting device power part was implemented in practice of Russian electromechanical engineering. The scope of use and advantages of brushless nonconventionally combined exciting devices is shown.Item Surface Plasmon Resonance of Nanoshell Particles with PMMA-Graphene Core(University of West Bohemia, 2013) Tarparelli, Richard; Iovine, Renato; La Spada, Luigi; Vegni, LucioIn this contribution we propose a numerical investigation of a new type of nanoshell particles. The structure consists of a core/shell particle with a PMMA (PolyMethyl MethAcrylate)-Graphene core and Au thin shell. The proposed particles exhibit a strong near electric field intensification when an electromagnetic plane wave in the Visible regime is applied. The optical properties are evaluated and discussed in terms of resonant behavior and the near electric field distribution. Finally, the sensitivity performance of the structure is analyzed for biosensing applications.Item Study of Low Frequency Electric Field Treatment of Granular Materials(University of West Bohemia, 2013) Iatcheva, Ilona; Bojilov, Gancho; Saykova, IlonaThe aim of the work is precise investigation of low frequency electrical field treatment of natural granular materials (seeds and grains). The components of electric field strength, current density, power losses and mechanical force along the surface of the grain have been obtained and estimated. The theoretical approach is based on AC conduction theory. The local models of each elementary grain region accounted simultaneously for the dielectric system dispersion and conductive system contributions. The field distribution has been studied using the finite element method and QuickField 5.6 software package.Item Short term electricity forecasting using smart meter data(University of West Bohemia, 2013) Ząbkowski, Tomasz; Gajowniczek, KrzysztofSmart metering is a quite new topic that has grown in importance all over the world and it appears to be a remedy for rising prices of electricity. Forecasting electricity usage is an important task to provide intelligence to the smart gird. Accurate forecasting will enable a utility provider to plan the resources and also to take control actions to balance the electricity supply and demand. The customers will benefit from metering solutions through greater understanding of their own energy consumption and future projections, allowing them to better manage costs of their usage. In this proof of concept paper, our contribution is the proposal for accurate short term electricity load forecasting for 24 hours ahead, not on the aggregate but on the individual household level.Item Peculiarities of 3D finite element modeling of a synchronous reluctance motor with a distributed winding(University of West Bohemia, 2013) Dmitrievskii, Vladimir; Prakht, VladimirIn this paper a new approach to modeling a radial flux electrical machines is proposed. This approach significantly simplifies the geometry of the electrical machine winding due to removing the front parts domains.Item Neural controller implementation in embedded system with use of FPGA coprocessor(University of West Bohemia, 2013) Gugała, Karol; Swietlicka, Aleksandra; Kolanowski, Krzysztof; Karón, Igor; Majchrzycki, Mateusz; Rybarczyk, AndrzejIn this paper we propose implementation of neural control system as embedded system with coprocessor in extensible processing platform.Item Multiobjective Geometry Optimization of a SPMSM Using an Evolutionary Algorithm(University of West Bohemia, 2013) Caramia, Raffaele; Palka, Ryszard; Wardach, Martin; Piotuch, RafalThis paper presents a methodology for the optimization of a Surface mounted Permanent Magnet Synchronous Motor (SPMSM) with 4 poles and 24 slots. In particular, it is focused on a multiobjective optimization using a genetic algorithm developed in Matlab with Optimization Toolbox that is coupled with Maxwell 14. The first one has been used for the optimization and the post-processing of the data, the second one for the Finite Element (FE) analysis and for the geometry creation. Aim of the optimization was to maximize the nominal torque and minimize the mass of a motor.Item Measurement and computation of power losses in soft magnetic composite materials(University of West Bohemia, 2013) Dmitrievskii, Vladimir; Prakht, Vladimir; Klimarev, VladimirIn this paper a new macroscopic FEM-oriented methods of mathematical modeling and a classification of electrical losses in SMC materials is discussed, the experimental data are provided and its processing is considered.Item Mathematical modelling a single-phase flux reversal machine(University of West Bohemia, 2013) Dmitrievskii, Vladimir; Prakht, Vladimir; Dmitrievskii, AntonIn this paper a new FRM construction with the increased power-to-weight ratio is described. A technique of electromagnetic calculation based on solving magnetostatic problems is developed for this construction.Item Mathematical analysis of random telegraph noise in low-power applications of MOSFETs(University of West Bohemia, 2013) Engert, Sonja; Toepfer, Hannes; Granzner, Ralf; Schwierz, FrankSilicon MOSFETs are active switching elements which form the basis for most currently available digital circuits. Especially in information technology the growth in circuit complexity and data throughput leads to an increase in power consumption. For this reason, the energy efficiency of transistors has become a major design issue. A common way to increase the energy efficiency of these devices is to reduce the signal level, which finally leads to the so-called sub-threshold operation. An advantage of this approach is that it can be applied to common structures so that new device concepts are not necessarily required. However, the reduction in the signal level leads unavoidably to a degradation of the signal to noise ratio. Especially random telegraph noise has a significant influence on the circuit behavior. In this work this type of noise is studied mathematically. A stochastic simulation model was developed and a method was provided by which it can be determined how low the supply voltage can be chosen in order to keep the noise influence sufficiently low.
