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Tytuł:
Analysis of capacitance of a cryogenic by-pass line for SIS100 particle accelerator at FAIR
Autorzy:
Tomków, Ł.
Trojanowski, S.
Ciszek, M.
Chorowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/140368.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
line capacitance
superconducting bus-bars
particle accelerators
Opis:
Safety and operation efficiency of the particle accelerators strongly depend on the quality of the supplied electric current and is affected by the electric properties of all elements of the circuit. In this paper the capacitance of the superconducting bus-bars applied in the cryogenic by-pass line for the SIS100 particle accelerator at FAIR is analysed. The unit capacitance of the bus-bars is calculated numerically and found experimentally. A 2D numerical model of a cross-section of the cable is applied. The capacitance is found with three methods. The stored energy, electric displacement field and charge gathered on the surfaces of the device are calculated and analysed. The obtained values are consistent. Experimental measurements are performed using the resonance method. The measuring system is undamped using a negative conductance converter. Small discrepancies are observed between numerical and experimental results. The obtained values are within the requirements of the accelerator design.
Źródło:
Archives of Electrical Engineering; 2018, 67, 4; 803-814
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical-stress analytical modeling for the design of coils in power applications
Autorzy:
Bellan, D.
Powiązania:
https://bibliotekanauki.pl/articles/140401.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
coils
mechanical stress
analytical modeling
line traps
PLC
Opis:
Modern electrical-power systems are often exploited for transmitting highfrequency carrier signals for communications purposes. Series-connected air-core coils represent the fundamental component allowing such applications by providing a proper filtering in the frequency domain. They must be designed, however, to withstand also the line short-circuit current. When a high-magnitude current flows through a coil, strong mechanical stresses are produced within the conductor, leading to possible damage of the coil. In this paper, an approximate analytical model is derived for the relationship between the maximum mechanical stress and the electrical/geometrical parameters of the coil. Such a model provides the guidelines for a fast and safe coil design, whereas numerical simulations are only needed for the design refinement. The presented approach can be extended to other applications such as, for example, the mechanical stress resulting from the inrush currents in the coils of power transformers.
Źródło:
Archives of Electrical Engineering; 2014, 63, 4; 579-590
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Method of estimating the exposure of the natural environment to 50 Hz electric and magnetic fields in power systems with distributed and centralized generations
Autorzy:
Zeńczak, M.
Powiązania:
https://bibliotekanauki.pl/articles/140965.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
distributed generation
electric field
magnetic field
power line
Opis:
The development of a distributed generation will influence the structure of the power transmission and distribution network. Distributed sources have lower power and therefore the lines of lower voltage are used. Therefore, the electric field intensity near such lines is lower. On the other hand magnetic field intensity may prove essential. The main aim of the paper is to present a method estimating the “ballast” of the natural environment at 50 Hz electric and magnetic fields in the power system, with distributed and centralized generation in real operating conditions.
Źródło:
Archives of Electrical Engineering; 2016, 65, 2; 295-304
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic field of complex helical conductors
Autorzy:
Budnik, K.
Machczyński, W.
Powiązania:
https://bibliotekanauki.pl/articles/141527.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Biot-Savart law
magnetic flux density
helical line
Opis:
Transmission of the electric power is accompanied with generation of low –frequency electromagnetic fields. Electromagnetic compatibility studies require that the fields from sources of electric power be well known. Unfortunately, many of these sources are not defined to the desired degree of accuracy. This applies e.g. to the case of the twisted-wire pair used in telephone communication; already practiced is twisting of insulated high-voltage three phase power cables and single-phase distribution cables as well. The paper presents a theoretical study of the calculation of magnetic fields in vicinity of conductors having helical structure. For the helical conductor with finite length the method is based on the Biot-Savart law. Since the lay-out of the cables is much more similar to a broken line than to strait line, in the paper the magnetic flux densities produced by helical conductor of complex geometry are also derived. The analytical formulas for calculating the 3D magnetic field can be used by a software tool to model the magnetic fields generated by e.g. twisted wires, helical coils, etc.
Źródło:
Archives of Electrical Engineering; 2013, 62, 4; 533-540
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An approach to power system harmonic analysis based on triple-line interpolation discrete Fourier transform
Autorzy:
Liu, Ling
Zhang, Jinsong
Powiązania:
https://bibliotekanauki.pl/articles/2135741.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
electrical harmonic estimation
interpolation DFT
triple-line interpolation
Opis:
The discrete Fourier transform (DFT) is a principal method for power system harmonic analysis. The fundamental frequency of the power system increases or decreases following load changes during normal operation. It is difficult to achieve synchronous sampling and integer period truncation in power harmonic analysis. The resulting spectrum leakage affects the accuracy of the measurement results. For this reason, a windowed interpolation DFT method for power system harmonic analysis to reduce errors was presented in this paper. First, the frequency domain expression of the windowed signal Fourier transform is analyzed. Then, the magnitude of the three discrete spectrum lines near the harmonic frequency point is used to determine the accurate position of the harmonic spectrum. Then, the calculation of the amplitude, frequency, and phase of harmonics is presented. The tripleline interpolation DFT can improve the accuracy of electrical harmonic analysis. Based on the algorithm, the practical rectification formulas were obtained by using the polynomial approximation method. The simulation results show that the fast attenuation of window function sidelobe is the key to reduce the error. The triple-line interpolation DFT based on Hanning, Blackman, Nuttall 3-Term windows has higher calculation accuracy, which can meet the requirements of electrical harmonic analysis.
Źródło:
Archives of Electrical Engineering; 2022, 71, 3; 549--558
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Load flow and contingency analysis for transmission line outage
Autorzy:
Aeggegn, Dessalegn Bitew
Salau, Ayodeji Olalekan
Gebru, Yalew
Powiązania:
https://bibliotekanauki.pl/articles/140622.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
contingency analysis
DIgSILENT software
line outage
Newton Raphson method
Opis:
In recent years, power systems have been pushed to operate above their limits due to the increase in the demand for energy supply and its usage. This increase is accompanied by various kinds of obstructions in power transmission systems. A power system is said to be secured when it is free from danger or risk. Power systems security deals with the ability of the system to withstand any contingencies without any consequences. Contingencies are potentially harmful disturbances which occur during the steady state operation of a power system. Load flow constitutes the most important study in a power system for planning, operation, and expansion. Contingency selection is performed by calculating two kinds of performance indices; an active performance index (PIP) and reactive power performance index (PIV) for a single transmission line outage. In this paper, with the help of the Newton Raphson method, the PIP and PIV were calculated with DIgSILENT Power Factory simulation software and contingency ranking was performed. Based on the load flow results and performance indexes, the Ethiopian Electric Power (EEP) North-West region network is recommended for an upgrade or the reactive power or series compensators should be constructed on the riskiest lines and substations.
Źródło:
Archives of Electrical Engineering; 2020, 69, 3; 581-594
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reliable digital dead-time generator for the GaN HEMTs based H-bridge converters
Autorzy:
Svarny, Jiri
Powiązania:
https://bibliotekanauki.pl/articles/949890.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
dead-time generator
delay-line
GaN HEMTs
H-bridge driver
Opis:
The paper deals with hardware solution of a fully digital dead-time generator. The circuit is applicable to the H-bridges based on any type of semiconductor switching devices including SiC, IGBT, Si-MOSFET and up-to-date GaN HEMTs. The generation of dead-times is ensured by commercially available silicon delay lines. High temperature stability is obtained by self-compensation of propagation delay of logic elements thanks to the symmetry of design topology. The circuit can be set-up to generate dead-times in the range from 10 ns to 500 ns. Longer dead-times are also available by simple cascading of the silicon delay lines. The key motivation for development of the circuit was unavailability of ready to use integrated solutions on the market. Moreover, contrary to the other solutions the proposed circuit is immune to prospective oscillations of an input PWM signal. The paper brings a detailed analysis of the circuit principle, results of the verification of a sample solution and an example of practical application as well.
Źródło:
Archives of Electrical Engineering; 2020, 69, 4; 781-792
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamic and steady state performance comparison of line-start permanent magnet synchronous motors with interior and surface rotor magnets
Autorzy:
Ogbuka, C.
Nwosu, C.
Agu, M.
Powiązania:
https://bibliotekanauki.pl/articles/141537.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
PMSM
line-start
damper winding
airgap torque
reluctance torque
saliency
Opis:
A comprehensive comparison of the dynamic and steady state performance characteristics of permanent magnet synchronous motors (PMSM) with interior and surface rotor magnets for line-start operation is presented. The dynamic model equations of the PMSM, with damper windings, are utilized for dynamic studies. Two typical loading scenarios are examined: step and ramp loading. The interior permanent magnet synchronous motor (IPMSM) showed superior asynchronous performance under no load, attaining faster synchronism compared to the surface permanent magnet synchronous motor (SPMSM). With step load of 10 Nm at 2 s the combined effect of the excitation and the reluctance torque forced the IPMSM to pull into synchronism faster than the SPMSM which lacks saliency. The ability of the motors to withstand gradual load increase, in the synchronous mode, was examined using ramp loading starting from zero at 2 s. SPMSM lost synchronism at 12 s under 11 Nm load while the IPMSM sustained synchronism until 41 seconds under 40 Nm load. This clearly suggests that the IPMSM has superior load-withstand capability. The superiority is further buttressed with the steady state torque analysis where airgap torque in IPMSM is enhanced by the reluctance torque within 90E to 180E torque angle.
Źródło:
Archives of Electrical Engineering; 2016, 65, 1; 105-116
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Voltage induced by currents in power-line sagged conductors in nearby circuits of arbitrary configuration
Autorzy:
Budnik, K.
Machczyński, W.
Szymenderski, J.
Powiązania:
https://bibliotekanauki.pl/articles/140488.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power line
catenary
vector potential
overhead circuit
induced voltage
mutual inductance
Opis:
The study presents a calculation method of the voltage induced by power-line sagged conductor in an inductively coupled overhead circuit of arbitrary configuration isolated from ground. The method bases on the solution utilizing the magnetic vector potential for modeling 3D magnetic fields produced by sagging conductors of catenary electric power lines. It is assumed that the equation of the catenary exactly describes the line sag and the influence of currents induced in the earth on the distribution of power line magnetic field is neglected. The method derived is illustrated by exemplary calculations and the results obtained are partially compared with results computed by optional approach.
Źródło:
Archives of Electrical Engineering; 2015, 64, 2; 227-236
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fault location technique using GA-ANFIS for UHV line
Autorzy:
Banu, G.
Suja, S.
Powiązania:
https://bibliotekanauki.pl/articles/141254.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
GA – ANFIS
fault location
Fault resistance
one end data
UHV line
Opis:
This paper presents an improved approach for locating and identifying faults for UHV overhead Transmission line by using GA-ANFIS. The proposed method uses one end data to identify the fault location. The ANFIS can be viewed either as a Fuzzy system, neural network or fuzzy neural network FNN. The integration with neural technology enhances fuzzy logic system on learning capabilities are proposed to analyze the UHV system under different fault conditions. The performance variation of two controllers in finding fault location is analyzed. This paper analyses various faults under different conditions in an UHV using Matlab/simulink. The proposed method is evaluated under different fault conditions such as fault inception angle, fault resistance and fault distance. Simulation results confirm that the proposed method can be used as an efficient for accurate fault location on the transmission line.
Źródło:
Archives of Electrical Engineering; 2014, 63, 2; 247-262
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of the impact of 220 kV SISFCL on the distance protection for transmission line
Autorzy:
Luo, Y.
Shi, T.
Huang, L.
Powiązania:
https://bibliotekanauki.pl/articles/141728.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
SISFCL
distance protection
EMTDC/PSCAD
220 kV transmission line
setting method
Opis:
As the most typical application of superconducting technology, the Saturated Iron core Superconducting Fault Current Limiter (SISFCL) is a kind of ideal high voltage limiter, which can achieve noticeable limiting endless stream and has wide application prospect. However, the selectivity and sensitivity of the distance protection (DP) in the high voltage transmission network would be affected by the impedance characteristics of SISFCL. For these problems, firstly the structure and the working principle of the SISFCL are introduced briefly. Secondly, the impact mechanisms of 220 kV SISFCL on the original distance protection for the transmission line (TL) are analyzed. Then two methods of eliminating influences are deduced from the previous analysis and an improved setting method based on SISFCL for distance protection is proposed. Finally, we used EMTDC/PSCAD software to build the 220 kV SISFCL and distance protection model in the transmission network. The simulation results demonstrate that the proposed setting strategy can effectively improve the selectivity and sensitivity of distance protection and provide a reference for the practical applications of SISFCL applied to the transmission line.
Źródło:
Archives of Electrical Engineering; 2018, 67, 1; 151-163
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of inductances and induced currents in cryogenic by-pass line for SIS100 particle accelerator at FAIR
Autorzy:
Tomków, Łukasz
Trojanowski, Stanisław
Ciszek, Marian
Chorowski, Maciej
Powiązania:
https://bibliotekanauki.pl/articles/141153.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
line inductance
mutual inductance
induced currents
superconducting bus-bars
particle accelerators
Opis:
Quality of electric current delivered to the magnets of a particle accelerator is essential for safety and reliability of its operation. Even small discrepancies strongly affect the properties of particle beams. One of the sources of the disturbances is the appearance of induced currents caused by the electromagnetic interactions between the elements of the machine. In this paper the calculations of induced currents in by-pass lines of a SIS100 particle accelerator are presented. In order to find the values of the currents the self-inductances and mutual inductances of the by-pass lines are found. Due to the complex geometry of the line, especially of Ω-shaped dilatations, the numerical approach was employed. The calculations show that the size of induced currents increases with the distance between the cables in an individual bus-bar. The maximum discrepancy of the magnetic field in a dipole magnet is found to be 7.7 μT. The decrease of distance between the cables allows one to obtain a discrepancy of 1.2 μT.
Źródło:
Archives of Electrical Engineering; 2019, 68, 3; 485-496
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimization of electric and magnetic field intensities in proximity of power lines using genetic and particle swarm algorithms
Autorzy:
Król, K.
Machczyński, W.
Powiązania:
https://bibliotekanauki.pl/articles/141588.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
power line
electric field
magnetic field
optimization
genetic algorithm
particle swarm algorithm
Opis:
The paper presents optimization of power line geometrical parameters aimed to reduce the intensity of the electric field and magnetic field intensity under an overhead power line with the use of a genetic algorithm (AG) and particle swarm optimization (PSO). The variation of charge distribution along the conductors as well as the sag of the overhead line and induced currents in earth wires were taken into account. The conductor sag was approximated by a chain curve. The charge simulation method (CSM) and the method of images were used in the simulations of an electric field, while a magnetic field were calculated using the Biot–Savart law. Sample calculations in a three-dimensional system were made for a 220 kV single – circuit power line. A comparison of the used optimization algorithms was made.
Źródło:
Archives of Electrical Engineering; 2018, 67, 4; 829-843
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Design of broadband power line communication module for automatic meter reading
Autorzy:
Chen, Xia
Liu, Ling
Powiązania:
https://bibliotekanauki.pl/articles/949869.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
automatic meter reading
low-power consumption
long-distance transmission
power line communication
Opis:
Low-power consumption and long-distance transmission are two problems that have to be solved by the application of broadband power line communication for the automatic meter reading system. To reduce the power consumption of the communication module, based on the analysis of the composition of the power consumption, some methods are proposed. From the communication chip level and the module circuit level, the design scheme of low-power consumption is given. To solve the problem of transmission distance, a frequency band of 2.44 MHz~5.6 MHz is used as the main working frequency band. The communication module supports multiple frequency bands. Using this feature, the optimal frequency band is adaptively selected for communication and automatic switching, which further improve the transmission distance. Field application shows that the above methods effectively decrease the power consumption of the communication module and extend the transmission distance.
Źródło:
Archives of Electrical Engineering; 2020, 69, 4; 771-780
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modeling of frequency response of transformer winding with axial deformations
Autorzy:
Gawrylczyk, K. M.
Banaszak, S.
Powiązania:
https://bibliotekanauki.pl/articles/140733.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
transformer
winding
frequency response analysis (FRA)
lumped parameters method
transmission line method
Opis:
One of important methods used for diagnostics of a transformer’s active part is Frequency Response Analysis (FRA). It allows to determine the mechanical condition of windings, their displacements, deformations and electric faults, as well as some problems with internal leads and connections, core and bushings. Still pending problem is interpretation of measurements results. One of approaches is application of computer modeling to simulate various failure modes and connected with them changes in FRA response. The paper presents two types of models, one based on lumped parameters with RLC elements, and one based on distributed parameters with TLM method. Both methods give similar results, comparable to real measurements of simulated coil.
Źródło:
Archives of Electrical Engineering; 2014, 63, 1; 5-17
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł

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