Skocz do pozycji: 1.

Tytuł:

The modeling of centrifugal pump transients

Autorzy:

Szymczyk, J.
Karaśkiewicz, K.

Powiązania:

https://bibliotekanauki.pl/articles/175255.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

rotodynamic pumps
complete pump characteristics
transients

Opis:

Centrifugal pumps are part of larger hydraulic systems. These hydraulic machines can work not only in the pumping mode but in a number of other modes whose job description is possible using complete characteristics. Some of these modes, such as the turbine mode and the reversed turbine mode, may have practical significance. Knowledge of the transition from one steady state to another state allows to estimate instantaneous values such as, e.g., flow current and torque, which may be even a few times higher than nominal. The principal issues in these transients are amplitudes of parameters of these pumps and the time constants associated with the characteristics of the system.

Źródło:

Transactions of the Institute of Fluid-Flow Machinery; 2015, 130; 83-92
0079-3205

Pojawia się w:

Transactions of the Institute of Fluid-Flow Machinery

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 2.

Tytuł:

Improved method for simulating transients of turbulent pipe flow

Autorzy:

Zarzycki, Z.
Kudźma, S.
Urbanowicz, K.

Powiązania:

https://bibliotekanauki.pl/articles/280935.pdf

Data publikacji:

2011

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

unsteady pipe flow
transients
waterhammer
efficient numerical simulation

Opis:

The paper presents the problem of modelling and simulation of transients during turbulent fluid flow in hydraulic pipes. The instantaneous wall shear stress on a pipe wall is presented in the form of integral convolution of a weighting function and local acceleration of the liquid. This weighting function depends on the dimensionless time and Reynolds number. Its original, very complicated mathematical structure is approximated to a simpler form which is useful for practical engineering calculations. The paper presents an efficient way to solve the integral convolution based on the method given by Trikha (1975) for laminar flow. An application of an improved method with the use of the Method of Characteristic for the case of unsteady flow (water hammer) is presented. This method is characterised by high efficiency compared to traditional numerical schemes.
Artykuł przedstawia zagadnienie modelowania i symulacji przebiegów przejściowych podczas turbulentnego przepływu cieczy w przewodach ciśnieniowych. Chwilowe naprężenie styczne na ściance przewodu przedstawiono w postaci całki splotowej z funkcji wagi i przyspieszenia cieczy. Funkcja wagi dla naprężenia stycznego na ściance przewodu zależy od czasu bezwymiarowego i liczby Reynoldsa. Ma ona zawiłą postać matematyczną, dlatego aproksymowano ją do prostszej postaci, przydatnej do praktycznych obliczeń inżynierskich. Przedstawiono efektywny sposób rozwiązania całki splotowej, opierając się na metodzie podanej przez Trikha (1975) dla przepływu laminarnego. Podano zastosowanie ulepszonej metody symulacji naprężenia stycznego do metody charakterystyk podczas uderzenia hydraulicznego. Charakteryzuje się ona dużą efektywnością w stosunku do metody tradycyjnej.

Źródło:

Journal of Theoretical and Applied Mechanics; 2011, 49, 1; 135-158
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 3.

Tytuł:

Comparison of transformer modeling on riser pole arresters behavior during switching transients

Autorzy:

Abbaszadeh, A.
Abedi, M.
Doustmohammadi, A.

Powiązania:

https://bibliotekanauki.pl/articles/140474.pdf

Data publikacji:

2017

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

arresters
ATP software
ferroresonance
transformer
power system transients

Opis:

Arresters are widely used in power systems to protect other equipment against overvoltages. However, in some conditions, they can’t operate successfully. One of the disturbances leading to the failure of the riser pole arresters is the ferroresonance overvoltages. In this paper, at first the influence of different transformer simulation models of ATP software on the occurrence of ferroresonance is studied and then the effect of ferroresonance on the riser pole arrester has been scrutinized through the thermal and electrical performance of the arrester in an underground distribution system. The results show that the arrester temperature rises due to energy dissipation in a ferroresonance circumstance, which indeed may result into the explosion of the arrester. Also, applying different models of the transformer in the ATP software and comparing the results, it is shown that the available models do not show the same effect on the arrester.

Źródło:

Archives of Electrical Engineering; 2017, 66, 4; 717-730
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 4.

Tytuł:

Modeling transients in MV resonantly grounded industrial grid during single line to ground faults

Autorzy:

Warecki, Jurij
Gajdzica, Michał

Powiązania:

https://bibliotekanauki.pl/articles/377060.pdf

Data publikacji:

2019

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

electrical grid
grounding methods
transients overvoltage
transient intermittent faults

Opis:

Medium voltage distribution power grids mostly operate with ungrounded neutral points of transformer. The philosophy about these power supply systems based on the assumption that the electrical grid is more reliable. However the practice of operation showed that currents of single phase or multiple faults to ground depend mostly on the earth capacitances of cables connected to power grid and configuration and structure in relation to the main substation buses. Moreover, this kind of arcing ground faults on the ungrounded system causes transient overvoltages several times than nominal value. In the consequence, it may be dangerous for the electrical devices connected to the power system. The article focuses on the transient impact the equipment insulation due to faults in the middle voltage industrial grid with adjustable speed drives. The examination results of transient voltages across the system was presented. The Matlab/ Simulink Software was used to modeling system behavior during intermittent faults.

Źródło:

Poznan University of Technology Academic Journals. Electrical Engineering; 2019, 98; 65-75
1897-0737

Pojawia się w:

Poznan University of Technology Academic Journals. Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 5.

Tytuł:

Effect of Hydraulic Characteristics on Fluid Transients Analysis under Different Types of Control Valves

Autorzy:

Al-Zaidi, Basim M.
Ismaeel, Abaas J.

Powiązania:

https://bibliotekanauki.pl/articles/2202314.pdf

Data publikacji:

2022

Wydawca:

Polskie Towarzystwo Inżynierii Ekologicznej

Tematy:

hydraulic characteristics
fluid transients
valve

Opis:

In this study, several types of valves were used to study the impact of the valves types and closure characteristics on fluid transients. The valve closure curves, which are the variation of the effective valve opening as a function of percentage opening area, were derived for different selected valves. Six different types of valves were selected to study the effect of the valves types on fluid transient conditions. For simplification, a very simple pipeline system was assumed and presented in this study. The system is about two pipes connected in a series junction and they take the water from a constant-level reservoir at upstream and a valve at downstream. The duration of valve closure was taken as six seconds which plays an important role in the pressure development in the system. A method of characteristics is applied to compute the transient conditions under gradual closure of the valves. Valve data of various forms were compiled and reported as discharge and headloss coefficients as a function of valve opening. The effect of valve geometry and operation on the relative valve opening were compared. Discharge and headloss coefficients were also compared between valve types. The study concluded that transient conditions depend on the valve type. The comparison between the results of all valve types indicated that the changes in pressure and discharges depend on valve type where there is a difference in effective valve opening. It can be concluded that the valve with the highest value of valve effective opening has less effect on transient conditions, i.e., the faster changes of effective valve opening the larger the effect on transient conditions (discharge and the greater the magnitude of the pressure wave). This study would help to select the property valve in pipeline design.

Źródło:

Journal of Ecological Engineering; 2022, 23, 12; 111--123
2299-8993

Pojawia się w:

Journal of Ecological Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 6.

Tytuł:

Hydraulic transients analysis in pipe networks by the method of characteristics (MOC)

Autorzy:

Wichowski, R.

Powiązania:

https://bibliotekanauki.pl/articles/240954.pdf

Data publikacji:

2006

Wydawca:

Polska Akademia Nauk. Instytut Budownictwa Wodnego PAN

Tematy:

hydraulic transients
method of characteristics
single pipe
experimental measurement
pipe networks
numerical simulations

Opis:

The paper presents results of an experimental and theoretical study of the hydraulic transients in straight pipes and numerical simulations of unsteady flow in pipe networks. A mathematical model consists of a set of partial differential equations of hyperbolic type, which have been transformed by the method of characteristics into ordinary differential equations which are solved by the predictor-corrector method. Experimental tests have been performed, in order to examine the hydraulic transients phenomenon, in a single straight steel pipe. The experiments were carried out in the hydraulic laboratory of the Institute of Water Supply and Water Engineering, Environmental Engineering Faculty, Warsaw University of Technology. The numerical results show that the presented one dimensional model for a single pipe correctly describes the phenomenon since there is a good agreement with experimental maximum and minimum oscillations. In the paper, selected exemplary equations in a difference form for the pipe networks are also presented. One calculation example is given relating to the complex water-pipe network consisting of 17 loops, 48 pipelines and 33 nodes, supplied by two independent sources. Water-hammer throughout the whole pipeline network was caused by closing the gate valve at mid-point of one selected pipe. The results of the numerical calculations are presented in graphic form with respect to the final cross-sections of pipes.

Źródło:

Archives of Hydro-Engineering and Environmental Mechanics; 2006, 53, 3; 267-291
1231-3726

Pojawia się w:

Archives of Hydro-Engineering and Environmental Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 7.

Tytuł:

Transients under energizing multiple power filter circuits

Autorzy:

Warecki, J.
Gajdzica, M.

Powiązania:

https://bibliotekanauki.pl/articles/97327.pdf

Data publikacji:

2016

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

capacitor
reactor
harmonic filter
C–type filter
Static Var Compensator
transient overcurrent
transient overvoltage
dynamic overcurrent
dynamic overvoltage
switching transients

Opis:

The practice of operating reactive power compensation systems involving passive multiple filter circuits (FC) configured by single–tuned filters has shown, that it’s energizing can cause damage of the filter components. Impact of feasible FC configurations, including FC with a C–type filter, on switching overvoltages and overcurrents under the harmonic filters energizing were analyzed. Influence of the filters tuning on transient behavior has been shown. The transient analysis has been carried out by simulating of the FC within Matlab/Simulink software.

Źródło:

Computer Applications in Electrical Engineering; 2016, 14; 89-100
1508-4248

Pojawia się w:

Computer Applications in Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 8.

Tytuł:

Transients in Transformers with Non-Uniform Inductance and Capacitance Distributions

Autorzy:

Saied, M. M.

Powiązania:

https://bibliotekanauki.pl/articles/262695.pdf

Data publikacji:

2017

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Tematy:

distributed parameter circuits
electromagnetic transients
integro-differential equations
modeling
mutual parameters
non-uniform
power transformers
transient response
winding

Opis:

The electromagnetic transients in transformer windings exhibiting location–dependent inductances and capacitances are investigated in the time domain. Analytical functions describing this dependence are assumed and incorporated in the two integro–differential equations governing the transient voltage and current distributions. The boundary conditions are available from the source initiating the transients and the winding’s end termination. A numerical procedure is applied in order to get frequency domain solutions for the voltage and current in the form of Interpolating and Parametric Functions. The numerical Laplace inversion is then applied to these s–domain expressions. Results pertinent to transients initiated by step- and double-exponential impulse sources are presented and discussed. All possible transformers’ neutral connections are considered. The possible error introduced by neglecting either or both of the inductance and capacitance non-uniformities is addressed. Results indicate that the main error is attributed to neglecting the inductance non-uniformity, whereas the impact of the capacitance non-uniformity is relatively small. In most cases, the winding’s copper and insulation losses have a small effect on the transient response.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2017, 20, 1; 7-14
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 9.

Tytuł:

Numerical criterion for the duration of non-chaotic transients in ODEs

Autorzy:

Szczebiot, Ryszard
Kaczyński, Roman
Gołdyn, Leszek

Powiązania:

https://bibliotekanauki.pl/articles/2204683.pdf

Data publikacji:

2022

Wydawca:

Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej

Tematy:

numerical criterion
non-chaotic transients
limit cycle
ODEs systems
Van der Pol oscillator

Opis:

The paper proposes an original numerical criterion for the duration analysis of non-chaotic transients based on the Euclidean norm of a properly defined vector. For this purpose, transient trajectories, prior to their entering a small neighbourhood of the limit cycle, are used. The vector has been defined with its components constituting the lengths of the sections, which connect the origin of the coordinate system with appropriately determined transient trajectory points. The norm of the vector for the analysis of non-chaotic transients has also been applied. As an assessment criterion of transients, the convergence of the norm to small neighbourhood of the limit cycle with the assumed accuracy is used. The paper also provides examples of the application of this criterion to the Van der Pol oscillators in the case of periodic oscillations.

Źródło:

Acta Mechanica et Automatica; 2022, 16, 4; 388--392
1898-4088
2300-5319

Pojawia się w:

Acta Mechanica et Automatica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 10.

Tytuł:

A Study on the Low Frequency Transients in Power Transformers and Some Protection-Related Issues

Autorzy:

Saied, M. M.

Powiązania:

https://bibliotekanauki.pl/articles/1203944.pdf

Data publikacji:

2014

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Tematy:

transformer cores
inrush current
protection
transients
modeling
equivalent circuit
low frequency
nonlinear model
simulation

Opis:

This paper presents typical results for the non-linear low frequency transients following the energization of power transformers. The three operating conditions of no-load, full-load and internal faults are considered. A direct analytical procedure is applied for solving the corresponding set of differential equations describing the transformers equivalent circuit. The core representation is based on the use of curve fitting applied to their magnetization curves. The results include plots versus time for the supply current, the core flux, the magnetizing current as well as the internal induced voltage. Moreover, graphs for the hysteresis loops relating the instantaneous values of both the excitation current and the core flux are given. An approach is also presented for the numerical determination of the amplitudes of the different harmonics existing in any of these signals utilizing the corresponding equidistant samples. As examples, the DC offset as well as harmonics up to the fourth order are considered. It is shown that several useful features can be extracted from the results in both the time and harmonic domains that can assist in differentiating between overcurrents resulting from short-circuits or inrush phenomena.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2014, 17, 2; 9-16
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 11.

Tytuł:

Analysis of Transients in a 4-Level Flying Capacitor Converter: Time Domain Approach. Part 2: Small Normalised Voltage Command

Autorzy:

Reznikov, Boris
Ruderman, Alex
Galanina, Valentina

Powiązania:

https://bibliotekanauki.pl/articles/1193863.pdf

Data publikacji:

2020

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

4-level DC–DC converter
flying capacitor
natural balancing
transients

Opis:

A 4-level flying capacitor converter (FCC) operation is considered on a base of discrete state-space model. A transition matrix is obtained for a pulse width modulation (PWM) period for small normalised voltage command values [0, 1/3]. The transition matrix elements are expanded into power series by small parameters. The matrix eigenvalues are presented in the form of power series as well. Six separate transients are constructed for six possible initial FCC states on a PWM period. Inductor current and capacitors’ voltage transients are found for the voltage source power-up as the arithmetic average of the six separate transients. Finally, the discrete solutions are replaced by equivalent continuous ones. Simple and accurate formulas for inductor current and capacitors’ voltage transients demonstrate good agreement with simulation results.

Źródło:

Power Electronics and Drives; 2020, 5, 40; 41-57
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 12.

Tytuł:

Analysis of Transients in a 4-Level Flying Capacitor Converter: Time Domain Approach. Part 1: Large Normalised Voltage Command

Autorzy:

Reznikov, Boris
Ruderman, Alex
Galanina, Valentina

Powiązania:

https://bibliotekanauki.pl/articles/1193906.pdf

Data publikacji:

2020

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

4-level DC-DC converter
flying capacitor
natural balancing
transients

Opis:

A 4-level flying capacitor converter (FCC) operation is considered on a base of discrete state-space model. A transition matrix is obtained for a pulse width modulation (PWM) period for large normalised voltage command values [1/3, 1). The transition matrix elements are expanded into power series by small parameters. The matrix eigenvalues are presented in the form of power series as well. Six separate transients are constructed for six possible initial FCC states on a PWM period. Inductor current and capacitors’ voltage transients are found for the voltage source power-up as the arithmetic average of the six separate transients. Finally, the discrete solutions are replaced by equivalent continuous ones. Simple and accurate formulas for inductor current and capacitors’ voltage transients demonstrate good agreement with simulation results.

Źródło:

Power Electronics and Drives; 2020, 5, 40; 27-40
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 13.

Tytuł:

Vibration transients of reservoir-pipe-valve system caused by water hammer

Autorzy:

Miao, Yang
Jiang, Yuncheng
Qiu, Zaihui
Pan, Jun
Wang, Lu
Han, Zhenrong
Li, Kun
Zhang, Li
Zhang, Xiaolu

Powiązania:

https://bibliotekanauki.pl/articles/1839616.pdf

Data publikacji:

2020

Wydawca:

Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej

Tematy:

reservoir-pipe-valve system (RPV system)
water hammer
vibration
transients

Opis:

A severe oscillation, accompanied with an abnormal “click” sound, of a fuel feeding pipe system during valve closing, when the feeding flowrate reaches a certain value, is observed experimentally. A fluctuation model in which stiffness and damping coefficients of the vibration system are time varying is proposed. Each coefficient is composed of two parts, one of which is constant and the other is time varying. Based on this model, simulation transients of the vibration displacement, velocity and pressure in the pipe are presented. Simulations of the pressure transients are compared with experimental data detected by pressure transducer, which shows that both have fluctuations in the transient process at a large flowrate.

Źródło:

Journal of Theoretical and Applied Mechanics; 2020, 58, 4; 1037-1048
1429-2955

Pojawia się w:

Journal of Theoretical and Applied Mechanics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 14.

Tytuł:

Analysis of IGCT turn-on transients in circuit configurations with series connected diodes

Autorzy:

Tschirley, S.
Bernet, S.

Powiązania:

https://bibliotekanauki.pl/articles/262745.pdf

Data publikacji:

2006

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Opis:

This paper describes the effect of series connected diodes and their balancing networks m the clamp circuit in IGCT converters. It is shown, that the balancing of the clamp diodes has other requirements than the balancing of the series connected freewheeling diodes in the switch cell. The dynamic and static balancing of the clamp diodes is analyzed in detail.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2006, 12, 2; 33-39
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 15.

Tytuł:

Double Injection Current Transients in a-Si:H

Autorzy:

Nekrašas, N.
Genevičius, K.
Juška, G.

Powiązania:

https://bibliotekanauki.pl/articles/1813197.pdf

Data publikacji:

2008-03

Wydawca:

Polska Akademia Nauk. Instytut Fizyki PAN

Tematy:

73.50.Gr

Opis:

In this work we present results of both computer modelling and experimental studies of double injection current transients in amorphous hydrogenated silicon thin layers.

Źródło:

Acta Physica Polonica A; 2008, 113, 3; 845-849
0587-4246
1898-794X

Pojawia się w:

Acta Physica Polonica A

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 16.

Tytuł:

Long lasting transients in power filter circuits

Autorzy:

Warecki, J.
Gajdzica, M.

Powiązania:

https://bibliotekanauki.pl/articles/97714.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

inrush current
arc fumace transformer
harmonic filter
switching transient

Opis:

The practice of operating AC electrical arc fumace power supply systems has shown that energizing unloaded fumace transformer can cause long lasting transients in filter circuits of static VAR compensators used in the supply systems. Examination of the supply system configuration impact on switching transient behaviour has been carried out by example of a 50 MVA arc fumace unit. The transient analysis has been carried out through simulating by Matlab/Simulink software.

Źródło:

Computer Applications in Electrical Engineering; 2014, 12; 324-333
1508-4248

Pojawia się w:

Computer Applications in Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 17.

Tytuł:

Output characteristics of step-down (Buck) power converter

Autorzy:

Janke, W.
Bączek, M.
Walczak, M.

Powiązania:

https://bibliotekanauki.pl/articles/201669.pdf

Data publikacji:

2012

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

DC-DC converters
output characteristics
load transients

Opis:

The output characteristics of switched-mode dc-dc buck power converter are discussed. The shape of output characteristics is especially important for converters used for supplying modern processors. An output impedance is usually used for description of output characteristics. Many efforts are described in the literature to obtain the satisfastory features of closed-loop output impedance. Another approach, presented in the paper, is based on the concept of the output voltage response corresponding to the load conductance change, and is expressed by hr transmittance. Simulations of output characteristics of the buck converter in frequency and in time-domain have been performed for the ideal case as well as for a more realistic situation, with the parasitic resistances of converter elements included. The measurement results differ substantially from characteristics calculated for an ideal converter and are in good consistency with simulations including parasitics.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 4; 751-755
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 18.

Tytuł:

Simulation of the magnetostrictive actuator transients

Autorzy:

Idziak, P.
Kowalski, K.
Nowak, L.
Barlak, M.
Pochrybniak, C.

Powiązania:

https://bibliotekanauki.pl/articles/377166.pdf

Data publikacji:

2015

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

actuators
magnetostriction
electromagnetic field
transient analysis

Opis:

The paper deals with a magnetostrictive fast-acting actuator applied as a driving device for plasma valve. The actuator is characterized by a relatively small displacement (les then 0.1 mm), but with a very short response time – below 0.1 ms. System is designed for so called “high intensity plasma pulses gun” which is applied in the area of plasma physics and material engineering [1]. A structure with an axisymmetrical actuator energised by discharged pulses of a capacitor has been proposed. The field-circuit mathematical model of the dynamic operation of the actuator has been applied. The model includes: the equation of transient electromagnetic field in a non-linear ferromagnetic material and equation of electric circuit. Using the Borland Delphi 9.0 environment, the computer software has been elaborated. Results of simulation are presented.

Źródło:

Poznan University of Technology Academic Journals. Electrical Engineering; 2015, 83; 23-30
1897-0737

Pojawia się w:

Poznan University of Technology Academic Journals. Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 19.

Tytuł:

Comparison of different methods for excitation of synchronous machines

Autorzy:

Schmuelling, S.
Kreischer, Ch.
Gołȩbiowski, M.

Powiązania:

https://bibliotekanauki.pl/articles/1367718.pdf

Data publikacji:

2015

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel

Tematy:

AC machines
Brushless machines
Electromagnetic transients
Excitation system
Power system simulation

Opis:

The energy turnaround in Germany leads to new operating conditions for small and medium synchronous generators. Since the electricity generation through renewable energy sources, such as wind or photovoltaic, is highly volatile, generators have to run up from standstill into rated operation within several minutes. Hence, it is necessary to compensate a lack of electricity generation caused by wrong weather forecasts. Usually, gas turbine systems provide this possibility. The generator is used as a starter engine due to the connection to a frequency inverter. The excitation current is often provided by static excitation systems. Thus, it is possible to start from standstill and run up the drive until the gas turbine is able to generate a positive torque. A new excitation concept, based on an induction machine with a 3-phase rotor winding, is able to provide an excitation current at 0 rpm and eliminates the need for brushes. To verify the applicability for power systems, both systems are compared under different aspects. The control of the excitation current at different speeds and the possibility to settle shaft oscillations after electrical faults are aspects researched in the paper at hand. A power system simulation is performed with a synchronous machine connected to a grid. Both excitation systems are modeled by equivalent circuit diagrams in Matlab Simscape.

Źródło:

Maszyny Elektryczne: zeszyty problemowe; 2015, 3, 107; 89-93
0239-3646
2084-5618

Pojawia się w:

Maszyny Elektryczne: zeszyty problemowe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 20.

Tytuł:

Accidents of loss of flow for the ETTR-2 reactor: deterministic analysis

Autorzy:

El-Messiry, M.

Powiązania:

https://bibliotekanauki.pl/articles/146728.pdf

Data publikacji:

2000

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

design base accidents
LOFA
loss of flow
pump coastdown
reactor transients

Opis:

The main objective for reactor safety is to keep the fuel in a thermally safe condition with adequate safety margins during all operational modes (normal-abnormal and accidental states). To achieve this purpose an accident analysis of different design base accident (DBA) as loss of flow accident (LOFA), is required for assessing reactor safety. The present work concerns this transients applied to Egypt Test and Research Reactor ETRR-2 (new reactor). An accident analysis code FLOWTR is developed to investigate the thermal behaviour of the core during such flow transients. The active core is simulated by two channels: 1 - hot channel (HC), and 2 - average channel (AC) representing the remainder of the core. Each channel is divided into four axial sections. The external loop, core plene, and core chimney are simulated by different dynamic lumps. The code includes modules for pump coast down, flow regimes, decay heat, temperature distributions, and feedback coefficients. FLOWTR is verified against results from RETRAN code, THERMIC code and commissioning tests for null transient case. The comparison shows a good agreement. The study indicates that for LOFA transients, provided the scram system is available, the core is shutdown safely by low flow signal (496.6 kg/s) at 1.4 s where the HC temperature reaches the maximum value of 45.64°C after shutdown. On the other hand, if the scram system is unavailable, and at t=47.33 s, the core flow decreases to 67.41 kg/s, the HC temperature increases to 164.02°C, and the HC clad surface heat flux exceeds its critical value of 400.00 W/cm2 resulting from the fuel burnout.

Źródło:

Nukleonika; 2000, 45, 4; 229-233
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 21.

Tytuł:

Transients impact on power filter circuit sizing

Autorzy:

Warecki, J.
Gajdzica, M.

Powiązania:

https://bibliotekanauki.pl/articles/97523.pdf

Data publikacji:

2015

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

capacitor
reactor
harmonic filter
transient and dynamic overvoltage
transient and dynamic overcurrent
equipment ratings

Opis:

The practice of operating multiple single-tuned filters in AC electrical arc furnace power supply systems has shown, that frequent energizing unloaded furnace transformer can cause damage of the filters. To examination of supply and filter system configuration impact on switching transient and dynamic overvoltages and overcurrents, an example of 50 MVA arc furnace unit was chosen. The transient analysis has been carried out by simulating within Matlab/Simulink Software. Using ANSI/IEEE Standards paper focuses on the selections of ratings for capacitors and air-core reactors used in multiple single-tuned harmonic filters configurations. Comparison of filter reactor and capacitor bank design based on steady state operation and transformer energizing was shown.

Źródło:

Computer Applications in Electrical Engineering; 2015, 13; 111-119
1508-4248

Pojawia się w:

Computer Applications in Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 22.

Tytuł:

Parks Transformation Based Formulation For Power Systems Transients Detection

Autorzy:

Ferraz, R. G.
Iurinic, L. U.
Filomena, A. D.
Bretas, A. S.

Powiązania:

https://bibliotekanauki.pl/articles/410529.pdf

Data publikacji:

2013

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

Park's transformation
transient detection
power systems

Opis:

This paper presents proposed developments of a new formulation and a full algorithm for transient detection by applying Parks transformation. This approach consist in transforming three-phase voltage or current signals into Parks components known as direct, quadrature, and zero axes components. The input signals are local measurements of a power transmission or distribution system. Then, transients are superimposed in three-phase signals that can be detected in Parks components through the finite difference between samples. A full algorithm for the transient detection is presented and envisions the possibility of being applied in real time. In order to demonstrate the proposed algorithms performance, four case studies are considered: capacitor energizing, distribution transformer energizing, permanent resistive fault, and high impedance fault. These cases were simulated on a typical Brazilian sub-transmission line using Alternative Transient Program. As demonstrated by the case studies, the proposed formulation introduces further improvements for transient detection in power systems.

Źródło:

Present Problems of Power System Control; 2013, 4; 5-23
2084-2201

Pojawia się w:

Present Problems of Power System Control

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 23.

Tytuł:

Obrazowanie termiczne stanów przejściowych przy załączaniu tyrystora
Thermal imaging of thyristor turn-on transients

Autorzy:

Kałuża, M.
Napiórkowski, K.

Powiązania:

https://bibliotekanauki.pl/articles/154464.pdf

Data publikacji:

2011

Wydawca:

Stowarzyszenie Inżynierów i Techników Mechaników Polskich

Tematy:

termowizja
przyrządy półprzewodnikowe mocy
thermovision
power semiconductor devices

Opis:

W artykule przedstawiono wyniki badań dotyczące możliwości zastosowania kamery termowizyjnej do rejestracji termogramów szybkich procesów przejściowych generacji ciepła w czasie załączania otwartej struktury półprzewodnikowej tyrystora. Badania wykazały możliwość rejestracji termogramów w czasie załączania przyrządu półprzewodnikowego mocy przy odpowiednim doborze niestandardowych ustawień pracy kamery termowizyjnej.
The paper presents the results of investigations on possible use of a thermal imaging camera for the recording of fast transient processes of heat generation during the switching of semiconductor structures in semiconductor power devices, based on measurements of a thyristor semiconductor structure. Using a measurement setup consisting of an IR camera and of a purpose build current pulse generator, the thermal behaviour of the T00-80 thyristor semiconductor structure during turn on was investigated. The thermograms were recorded at speeds reaching 1400 frames per second. Studies of the semiconductor structure of the thyristor mounted in a special holder showed the possibility of using a thermal camera for analyzing the behaviour of power semiconductor devices, however further increase in the temporal resolution of the recording process will be needed. One of the solutions will be to synchronize operation of a pulse generator and a thermal camera, including a controlled, variable time delay between current pulse generation and image acquisition.

Źródło:

Pomiary Automatyka Kontrola; 2011, R. 57, nr 10, 10; 1199-1201
0032-4140

Pojawia się w:

Pomiary Automatyka Kontrola

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 24.

Tytuł:

Określanie charakterystyk drganiowych silników turbinowych w stanach nieustalonych
Determining vibration characteristics in marine turbine engines in transients conditions

Autorzy:

Grządziela, A.

Powiązania:

https://bibliotekanauki.pl/articles/223192.pdf

Data publikacji:

2011

Wydawca:

Akademia Marynarki Wojennej. Wydział Dowodzenia i Operacji Morskich

Tematy:

silnik turbinowy
charakterystyki
drgania
turbine engine
characteristics
vibrations

Opis:

W artykule przedstawiono metodę wyznaczania charakterystyk drganiowych okrętowych turbinowych silników spalinowych. Zaproponowano sposób akwizycji danych z pomiarów w stanach nieustalonych oraz metodykę badań procesów drganiowych zachodzących w procesach zimnego i gorącego rozruchu oraz wybiegu wirnika wytwornicy spalin.
The paper presents a method for determining vibration characteristics in marine turbine engines. It proposes a way of data acquisition from measurements in transient conditions, as well as methodology for investigating vibration processes occurring under run-up and shut-down engine processes and rotor coasting of gas generator.

Źródło:

Zeszyty Naukowe Akademii Marynarki Wojennej; 2011, R. 52 nr 3 (186), 3 (186); 57-64
0860-889X

Pojawia się w:

Zeszyty Naukowe Akademii Marynarki Wojennej

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 25.

Tytuł:

On the Interaction Between Theory, Experiments, and Simulation in Developing Practical Learning Control Algorithms

Autorzy:

Longman, R. W.

Powiązania:

https://bibliotekanauki.pl/articles/908249.pdf

Data publikacji:

2003

Wydawca:

Uniwersytet Zielonogórski. Oficyna Wydawnicza

Tematy:

automatyka
robotyka
iterative learning control
ILC
2D systems
learning transients

Opis:

Iterative learning control (ILC) develops controllers that iteratively adjust the command to a feedback control system in order to converge to zero tracking error following a specific desired trajectory. Unlike optimal control and other control methods, the iterations are made using the real world in place of a computer model. If desired, the learning process can be conducted both in the time domain during each iteration and in repetitions, making ILC a 2D system. Because ILC iterates with the real world, and aims for zero error, the field pushes the limits of theory, modeling, and simulation, to predict the behavior when applied in the real world. It is the thesis of this paper that in order to make significant progress in this field it is essential that the research effort employ a coordinated simultaneous synergistic effort involving theory, experiments, and serious simulations. Otherwise, one very easily expends effort on something that seems fundamental from the theoretical perspective, but in fact has very little relevance to the performance in real world applications.

Źródło:

International Journal of Applied Mathematics and Computer Science; 2003, 13, 1; 101-111
1641-876X
2083-8492

Pojawia się w:

International Journal of Applied Mathematics and Computer Science

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 26.

Tytuł:

Investigation on ferroresonance due to power transformer energization in high voltage 400 kV transmission grid

Autorzy:

Polewaczyk, Mateusz
Robak, Sylwester
Szewczyk, Marcin

Powiązania:

https://bibliotekanauki.pl/articles/141509.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

ferroresonance
high voltage
Poincaré map
power system transients
PSCAD

Opis:

This paper presents a study on ferroresonance occurring in a high voltage 400 kV transmission grid due to energization of power transformer under no-load conditions. The system scenarios analyzed in the present paper are considered as critical for development and modernization plans as currently announced by the national grid operator in Poland. The PSCAD simulation model was developed and applied for several study cases of a system with double-circuit arrangement of a transmission line. It is shown that the ferroresonant oscillations can be initiated by two-phase switching operation of a line circuit breaker. The impact of the double-circuit length on the ferroresonance mode and severity is demonstrated with the use of the Poincaré map analysis and Short Time Fourier Transform. It is demonstrated that the length of the transmission line that is mutually coupled in the double-circuit arrangement has a significant impact on the ferroresonance occurrence and on its mode. As the ferroresonance can pose severe threat to the power system components due to the severe overvoltage and overcurrent oscillations, the analysis presented in this paper demonstrates the necessity of the ferroresonance analyses for any re-designed transmission system.

Źródło:

Archives of Electrical Engineering; 2019, 68, 4; 771-786
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 27.

Tytuł:

Combined monitoring and time-frequency analysis for transients in wind energy systems

Autorzy:

Łobos, T.
Sikorski, T.
Amarís, H
Alonso, M
Florez, D

Powiązania:

https://bibliotekanauki.pl/articles/1395766.pdf

Data publikacji:

2010

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

power quality monitoring
wind energy
wind power plant

Opis:

The aim of this paper is the application of selected time-varying power quality indices combined with detailed time-frequency analysis for assessment of transients in wind energy system. Presented proposition utilizes short-term harmonic distortion in voltage (STHDV) characteristic as an indicator for detail local time-frequency analysis of the transients. Introduced ideas can be treated as hybrid system absorbing both power quality indices and time-frequency representation.

Źródło:

Computer Applications in Electrical Engineering; 2010, 8; 261-269
1508-4248

Pojawia się w:

Computer Applications in Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 28.

Tytuł:

Analytical calculations of surges caused by direct lightning strike to underground intrusion detection system

Autorzy:

Aniserowicz, K.

Powiązania:

https://bibliotekanauki.pl/articles/200287.pdf

Data publikacji:

2019

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

lightning
transients
overvoltages
analytical modeling
underground cable
błyskawica
transjenty
przepięcia
modelowanie analityczne
kabel podziemny

Opis:

The paper presents an analysis of overvoltages caused by a direct lightning strike in intrusion detection system equipped with underground radiating cable sensors. Waveforms of currents and voltages in the system components are calculated using analytical formulas basing on a transmission-line model in the frequency domain. The time-domain waveforms are computed using the inverse fast Fourier transform (IFFT). Three network configurations of the intrusion detection system are analyzed.

Źródło:

Bulletin of the Polish Academy of Sciences. Technical Sciences; 2019, 67, 2; 263-270
0239-7528

Pojawia się w:

Bulletin of the Polish Academy of Sciences. Technical Sciences

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 29.

Tytuł:

Modelling of synchronous generators for the analysis of frequency transients above 1 Hz/s

Autorzy:

Assenkamp, Alf

Powiązania:

https://bibliotekanauki.pl/articles/2135729.pdf

Data publikacji:

2022

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

control system
distributed energy systems
frequency support
generator model
RoCoF
synchronous generators
synchronous machines

Opis:

Large synchronous generators are of high importance for the stability of power systems. They generate the frequency of the system and stabilize it in case of severe grid faults like trips of large in-feeders or loads. In distributed energy systems, in-feed via inverters will replace this generation in large parts. Modern inverters are capable of supporting grid frequency during severe faults by different means on the one hand. On the other hand, higher Rates of Change of Frequency (RoCoF) after incidents need to be accustomed by future systems. To be able to analyse the RoCoF withstand capability of synchronous or induction generators, suitable models need to be developed. Especially the control and excitation system model need enhancements compared to models proposed in standards like IEEE Std 421.5. This paper elaborates on the necessary modelling depth and validates the approach with example results.

Źródło:

Archives of Electrical Engineering; 2022, 71, 3; 687--700
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 30.

Tytuł:

Analysis of Transients in a Three-Level DC–DC Flying Capacitor Converter. Time Domain Approach

Autorzy:

Reznikov, Boris
Ruderman, Alexander
Galanina, Valentina

Powiązania:

https://bibliotekanauki.pl/articles/1193695.pdf

Data publikacji:

2019

Wydawca:

Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej

Tematy:

three-level DC–DC converter
flying capacitor
transient
natural balancing

Opis:

The paper considers a discrete state-space model for transients in a three-level flying capacitor DC–DC converter. A transition matrix is obtained for a pulse width modulation (PWM) period. The matrix elements are expanded into a power series using a selected small parameter. The matrix eigenvalues that determine the natural balancing dynamics transients are presented in the form of power series as well. Four separate transients are constructed based on four possible PWM period initial states (topologies). Inductor current and capacitor voltage transients are found for the voltage source power-up as the arithmetic average of the four separate transients. The discrete solutions are replaced by continuous ones. The resulting transients that are elementary functions of the circuit parameters, PWM period, and voltage reference demonstrate good agreement with the simulation results.

Źródło:

Power Electronics and Drives; 2019, 4, 39; 33-45
2451-0262
2543-4292

Pojawia się w:

Power Electronics and Drives

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 31.

Tytuł:

Fuel feed to diesel at a start regime

Autorzy:

Fedyanov, E.
Slavuckiy, V.
Kanygin, Z.

Powiązania:

https://bibliotekanauki.pl/articles/246126.pdf

Data publikacji:

2009

Wydawca:

Instytut Techniczny Wojsk Lotniczych

Tematy:

starting duty
features of process of giving
nozzle valve lifting
injection pressure
transients
cyclic fuel delivery

Opis:

Some factors defining starting properties of diesel engines are considered. Features of process of fuel feed on a starting mode are analyzed. Basic possibility of steering by processes of mixture forming and combustion is proved at a small speed of a crankshaft. Developed a design procedure of process of fuel feed in a diesel engine at a start regime. On the basis of the theory of transients in a fuel system, the reasons of deterioration of indicators of fuel feed process are explained at a start regime of diesel engine. Possibilities of a method of increase of initial pressure in a delivery highway by prostrating scrolling of a crankshaft with idle spray jets are investigated. The method of intensification of fuel feed process patented by authors used in diesel engine at a start regime. The results of numerical experiments confirming improvement of indicators of process of injection at high-speed speeding up of the pump of a high pressure are resulted: Increase maximum and an average pressure, cutting-down of duration of fuel feed process. The paper concentrates on possibility of improving fuel fed process at the starting regime by means of high speed forcing the fuel pump and the initial pressure rising by an earlier camshaft rotation with out of work injectors.

Źródło:

Journal of KONES; 2009, 16, 1; 111-116
1231-4005
2354-0133

Pojawia się w:

Journal of KONES

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 32.

Tytuł:

Study of transients in multiple power filter circuit comprising C-type filter

Autorzy:

Warecki, J.
Gajdzica, M.

Powiązania:

https://bibliotekanauki.pl/articles/377600.pdf

Data publikacji:

2018

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

capacitor
reactor
C–type filter
single-tuned passive filter
switching transient
transient overvoltage
transient overcurrent

Opis:

Passive filters are widely used to mitigate the effect of load harmonics on the supply power grid. Topology selection of the filters is based on the frequency bandwidth to be suppressed. Filter topologies comprising single-tuned filters and damped filters are the most popular in industrial power system applications. The article focuses on the influence of the damped C-type 2nd harmonic filter on the transients behavior under arc transformer energization in the arc furnace power supply system compensated by SVC. The examination results of transient currents and voltages across capacitors and reactors of the 3rd and 5th passive filters are compared for two topologies of the SVC filter circuits: with and without C-type filter. The Matlab/Simulink Software was used to modeling filter behavior during unload transformer switching-on.

Źródło:

Poznan University of Technology Academic Journals. Electrical Engineering; 2018, 95; 105-115
1897-0737

Pojawia się w:

Poznan University of Technology Academic Journals. Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 33.

Tytuł:

Characteristics simulations of the electrodynamic railgun different constructions and their measurement verification

Autorzy:

Piekielny, Paweł
Tomczuk, Bronisław
Waindok, Andrzej

Powiązania:

https://bibliotekanauki.pl/articles/27309948.pdf

Data publikacji:

2023

Wydawca:

Polska Akademia Nauk. Czasopisma i Monografie PAN

Tematy:

3D field analysis
analysis of transients
analytical models
electrodynamic accelerator
experimental verification
field-circuit modeling
projectile velocity

Opis:

Dynamic characteristics for three types of railgun constructions were simulated and measured in this work. The simplest construction is the iron-less (IL) railgun, while the two other ones (IC and ICPM) have an iron-core. The iron-core permanent magnet (ICPM) railgun additionally has permanent magnets. To compare their characteristics, similar dimensions of the rails and iron cores were adopted, and the same power supply system was used. Numerical magnetic field analyses and our analytical models have been used to determine the electromagnetic parameters. They were verified experimentally. The transient states of the railguns were studied with our field-circuit mathematical model, and their results were also verified by experiments.

Źródło:

Archives of Electrical Engineering; 2023, 72, 4; 951--969
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 34.

Tytuł:

Simulations of Fast Transients in typical 25 kV a.c. railway power supply system
Symulacje stanów nieustalonych w typowym 25 kV a.c.układzie zasilania trakcji

Autorzy:

Chmielewski, T.
Dziadkowiec, A.

Powiązania:

https://bibliotekanauki.pl/articles/266311.pdf

Data publikacji:

2013

Wydawca:

Politechnika Gdańska. Wydział Elektrotechniki i Automatyki

Tematy:

railway
lightning
PSCAD
trakcja
przepięcia piorunowe

Opis:

Railway power lines as any other outdoor overhead conductors are exposed to lightning strokes. Overvoltages generated by a lightning surge may severely decrease the overall system reliability due to possible damages of powering and signalling equipment. Hence an appropriate design of lightning protection is crucial. This paper presents computer simulations of lightning phenomenon (Fast Transients) in a typical railway catenary system conducted in PSCAD software. Detailed numerical model consisted of cables, overhead catenary lines, surge arresters, transformers and rails. A few modelling approaches were used and compared. The outcome of such analysis can be helpful in determining possible overvoltages in railway system along with a proposal of ratings and locations of additional surge arresters’ installation.
Treść artykułu skupia się na symulacyjnych badaniach przepięć piorunowych w sieci zasilania trakcji elektrycznej. W oparciu o model typowego systemu 25 kV a.c., przeprowadzono porównanie odpowiedzi układu w przypadku zmiany podejścia do modelowania elementów takich jak napowietrzna sieć trakcyjna, czy też szyny.

Źródło:

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej; 2013, 36; 43-46
1425-5766
2353-1290

Pojawia się w:

Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 35.

Tytuł:

Transformer Modelling for the Frequency and Transient Analyses, with Non-Uniform Inductance Emulating the Inter-Turn Magnetic Coupling

Autorzy:

Saied, M. M.

Powiązania:

https://bibliotekanauki.pl/articles/262677.pdf

Data publikacji:

2014

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Tematy:

distributed parameter circuits
frequency response
modeling
power system transients
power transformers
resonance
non-uniform

Opis:

A new procedure for analyzing power transformer windings with location-dependent circuit parameters, such as the series inductance, is presented. This dependence is introduced in order to take the inter-turn mutual inductive coupling into consideration. It can be expressed either by analytical expressions or even in a tabulated form. The paper addresses both the frequency and time domain analyses. They are based on replacing the winding by an adequate number of equivalent cascade connected two-ports. In contrast to the usual practice of applying the simple medium line representation, each of these two-ports is treated as a long transmission line. Their A, B, C, D generalized circuit constants will be therefore generally location-and frequency-dependent. The analyses will be conducted in the complex s-domain. The corresponding time-domain results can then be obtained by applying a numerical inverse Laplace transform. Expressions for the winding’s input impedance with different treatments of the transformer’s neutral point will be derived for any assumed number of the equivalent two-ports. Results pertinent to the frequency characteristics including the resonance frequencies are presented. The paper also describes the winding’s transient response to the application of two standard voltage stimuli. The suggested approach is validated by its application to a case study for which an analytical closed-form solution is available. The analysis of windings exhibiting nonuniformities in more than one equivalent.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2014, 17, 1; 1-11
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 36.

Tytuł:

Compared analysis of the transients and the steady states of squirrel-cage motor and LSPMSM

Autorzy:

Barański, M.
Idziak, P.
Łyskawiński, W.

Powiązania:

https://bibliotekanauki.pl/articles/97457.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

squirrel-cage motor
line start permanent magnet synchronous motor
starting process
heating
functional parameters

Opis:

In the paper the transients under starting process and the steady states of squirrel-cage motor (IM) and line start permanent magnet synchronous motor (LSPMSM) have been compared. The original stator of 3 kW induction motor type Sg 100L-4B, was used in both structures. In order to determine opportunities to increase energy parameters of LSPMSM the heating curves of both motors were compared. In LSPMSM the rotor with aluminum and copper cage was used. The basic operating parameters of the two structures which are characterized by identical stators were tested. Particular attention has been given to the transient under starting process. Efficiency, power factor and current in the stator windings obtained during measurements for both structures have been presented. The paper focuses on achieving a much higher output power for LSPMSM than an induction motor of the same size. The selected results of experimental tests were shown.

Źródło:

Computer Applications in Electrical Engineering; 2014, 12; 265-274
1508-4248

Pojawia się w:

Computer Applications in Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 37.

Tytuł:

Transients of electrical and mechanical quantities of a brushless DC motor - computations, measurements

Autorzy:

Ciurys, M.
Dudzikowski, I.

Powiązania:

https://bibliotekanauki.pl/articles/141324.pdf

Data publikacji:

2011

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

maszyna elektryczna
silnik bezszczotkowy
magnes trwały
silnik BLDC
obliczenia
pomiary
electrical machines
BLDC motors
permanent magnets
computations
measurements

Opis:

The paper presents a method of computing electrical and mechanical variables of BLDC motors. It takes into account electrical, magnetic and mechanical phenomena in the power supply-converter-BLDC motor-load machine system. The solution to the problem is the so-called circuit-field method. The results determined with the use of time stepping finite element method were used as the parameters of equations of the developed mathematical model. Losses in the motor, losses in transistors and diodes of the converter as well as the actual back EMF waveforms, variable moment of inertia and variable load torque are accounted for. The designed laboratory stand and the test results are presented in the paper. The experimental verification shows the correctness of the developed method, algorithm and program. The developed computational method is universal with respect to different electromechanical systems with cylindrical BLDC motors. It can be applied to electromechanical systems with BLDC motors operating at constant but also variable load torque and moment of inertia.

Źródło:

Archives of Electrical Engineering; 2011, 60, 1; 23-34
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 38.

Tytuł:

Transient recovery voltage analysis for various current breaking mathematical models: shunt reactor and capacitor bank de-energization study

Autorzy:

Oramus, P.
Chmielewski, T.
Kuczek, T.
Piasecki, W.
Szewczyk, M.

Powiązania:

https://bibliotekanauki.pl/articles/140943.pdf

Data publikacji:

2015

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

arc modelling
overvoltages studies
EMTP-ATP program
transients analysis

Opis:

Electric arc is a complex phenomenon occurring during the current interruption process in the power system. Therefore performing digital simulations is often necessary to analyse transient conditions in power system during switching operations. This paper deals with the electric arc modelling and its implementation in simulation software for transient analyses during switching conditions in power system. Cassie, Cassie-Mayr as well as Schwarz-Avdonin equations describing the behaviour of the electric arc during the current interruption process have been implemented in EMTP-ATP simulation software and presented in this paper. The models developed have been used for transient simulations to analyse impact of the particular model and its parameters on Transient Recovery Voltage in different switching scenarios: during shunt reactor switching-off as well as during capacitor bank current switching-off. The selected simulation cases represent typical practical scenarios for inductive and capacitive currents breaking, respectively.

Źródło:

Archives of Electrical Engineering; 2015, 64, 3; 441-458
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 39.

Tytuł:

Investigation of the stator inductances of the expanded Park model and an approach on parameter identification using the evolution strategy

Autorzy:

Schmuelling, Ch.
Kreischer, Ch.
Gołebiowski, M.

Powiązania:

https://bibliotekanauki.pl/articles/141147.pdf

Data publikacji:

2016

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

evolution strategy
FEM
Park equations
Park theory
synchronous machines
transients

Opis:

Commonly, the Park model is used to calculate transients or steady-state operations of synchronous machines. The expanded Park theory derives the Park equations from the phase-domain model of the synchronous machine by the use of transformations. Thereby, several hypothesis are made, which are under investigation in this article in respect to the main inductances of two different types of synchronous machines. It is shown, that the derivation of the Park equations from the phase-domain model does not lead to constant inductances, as it is usually assumed for these equations. Nevertheless the Park model is the most common analytic model of synchronous machines. Therefore, in the second part of this article a method using the evolution strategy is shown to obtain the parameters of the Park model.

Źródło:

Archives of Electrical Engineering; 2016, 65, 3; 585-599
1427-4221
2300-2506

Pojawia się w:

Archives of Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 40.

Tytuł:

The Transient Performance of Partially-Undergrounded Overhead Lines in the Presence of Corona

Autorzy:

Saied, Mohamed M.

Powiązania:

https://bibliotekanauki.pl/articles/262791.pdf

Data publikacji:

2019

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Tematy:

distributed parameter circuits
non-uniform lines
power transmission lines
line modeling
transients
power networks
mixed
overhead-cable lines
partial undergrounding
distributions
mathematica

Opis:

The paper presents a method for investigating the electromagnetic transients of partially under-grounded high voltage overhead transmission lines in the presence of corona. It is based on a time domain model in which the corona is simulated by distributed voltage-dependent shunt current sources. The line segments and the inserted cable section are represented by a single equivalent transmission element having location-dependent circuit parameters per unit length. The numerical solution of the resulting set of differential equations yields the distributions of the voltage, the longitudinal current and the shunt corona current (per unit length) as functions of location and time. The presented two-, three-dimensional and contour plots proved to be helpful in discussing these distributions and in identifying any eventual current and/or voltage concentrations. The developed computer code in Mathematica can handle any time waveform of the source initiating the transients, any line termination as well as any lengths of the overhead line and cable section.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2019, 21, 1; 1-8
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 41.

Tytuł:

Analiza procesów zachodzących podczas załączania transformatora pieca łukowego zasilanego z układu z filtrami wyższych harmonicznych
Transients analysis during arc furnace transformer energization in environment of harmonic filters

Autorzy:

Warecki, J.
Gajdzica, M.

Powiązania:

https://bibliotekanauki.pl/articles/377163.pdf

Data publikacji:

2014

Wydawca:

Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej

Tematy:

prąd rozruchowy
transformator piecowy
filtr wyższych harmonicznych

Opis:

Praktyka eksploatacji układów zasilania pieców łukowych prądu przemiennego pokazała, że wielokrotne komutacje technologiczne transformatorów piecowych mogą stać się przyczyną uszkodzenia transformatora systemowego i innych urządzeń sieci zasilającej. W pracy zbadano wpływ konfiguracji sieci zasilającej na charakter procesów przejściowych jednostki piecowej średniej mocy 50 MVA. Analizę zachodzących procesów przejściowych w układzie zasilania pieca łukowego przeprowadzono stosując model zrealizowany w pakiecie Matlab/Simulink.
The practice of operating AC electrical arc furnace power supply systems has shown that frequent energizing unloaded furnace transformer can cause damage of the system transformer and other system devices. To examination of supply system configuration impact on switching transient nature an example of 50 MVA arc furnace unit was chosen. The transient analysis has been carried out by simulating within Matlab/Simulink software.

Źródło:

Poznan University of Technology Academic Journals. Electrical Engineering; 2014, 79; 279-287
1897-0737

Pojawia się w:

Poznan University of Technology Academic Journals. Electrical Engineering

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 42.

Tytuł:

Modelowanie matematyczne procesów rozruchu układów napędowych podnośników budowlanych
Mathematical modelling of transients in drives of building elevating devices

Autorzy:

Kharchenko, Y.
Sobkowski, S.

Powiązania:

https://bibliotekanauki.pl/articles/328348.pdf

Data publikacji:

2005

Wydawca:

Polska Akademia Nauk. Polskie Towarzystwo Diagnostyki Technicznej PAN

Tematy:

podnośnik
układ napędowy
rozruch
modelowanie matematyczne
diagnostyka
elevator
drive syatem
starting-up
mathematical modelling
technical diagnostics

Opis:

W pracy rozpatruje się wyniki modelowania matematycznego procesów rozruchu układów napędowych podnośników budowlanych. Analizę zjawisk dynamicznych wykonano poprzez wspólne całkowanie równań ruchu elementów układu oraz równań stanu elektromagnetycznego silnika asynchronicznego. Zbadano wpływ masy ładunku i masy przeciwwagi na działające siły dynamiczne w linach.
Results of mathematical modelling of processes of start-up of drives of building elevating devices are analyzed. Calculation of dynamic processes is carried out by joint integration of the equations of movement of elements of systems and the equations of the electromagnetic phenomena in asynchronous engines. Influence of structure of the device and its mechanical characteristics on dynamic efforts in elastic parts is investigated.

Źródło:

Diagnostyka; 2005, 35; 37-42
1641-6414
2449-5220

Pojawia się w:

Diagnostyka

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 43.

Tytuł:

Control of operability of Peltier modules in cooling systems based on the analysis of transient operating modes

Autorzy:

Kuzichkin, Oleg Rudolfovich
Konstantinov, Igor Sergeevich
Vasilyev, Gleb Sergeevich
Surzhik, Dmitry Igorevich

Powiązania:

https://bibliotekanauki.pl/articles/1845461.pdf

Data publikacji:

2021

Wydawca:

Polska Akademia Nauk. Czytelnia Czasopism PAN

Tematy:

thermoelectric system
agriculture
complex
transients
peltier effect
identification algorithms

Opis:

The paper is devoted to the control of operability of Peltier modules based on the analysis of transient modes of their operation. Advantages of using low-power thermoelectric modules for the development of thermoelectric plants with adaptive control systems for the needs of the agricultural complex, which significantly reduce their cost characteristics, are shown. The problem of using the stationary mode of their operation, associated with the low efficiency of the modules, as well as the dynamic mode, associated with the presence of transient processes, is indicated. It is noted that overcoming this problem requires solution of the task of automation of reliability providing the well-known approaches to its solution are shown, for which the key advantages and disadvantages are given. An approach is proposed to complex control of the operability and quality of thermoelectric modules during their expluatation in three components of the physical process of thermoelectric conversion (Peltier thermoelectric effect, electrical and thermal transfer phenomena) by analyzing transients in the system based on identification algorithms. To justify it, the necessary equations and mathematical relations are given. Aprobating of the proposed approach was carried out experimentally by determining the time constants for operable and defective commercially available modules and showed its significant advantages over the standard verification procedure.

Źródło:

Archives of Thermodynamics; 2021, 42, 2; 31-42
1231-0956
2083-6023

Pojawia się w:

Archives of Thermodynamics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 44.

Tytuł:

Rozrusznik samochodowy z bezszczotkowym silnikiem prądu stałego
Car starter with brushless direct current motor

Autorzy:

Ciurys, M.
Dudzikowski, I.

Powiązania:

https://bibliotekanauki.pl/articles/320357.pdf

Data publikacji:

2006

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH

Tematy:

rozruszniki samochodowe
silniki bezszczotkowe
magnesy trwałe
obliczenia
stany dynamiczne
car starters
brushless direct current motors
permanent magnets
computations
transients

Opis:

Opracowano model matematyczny, algorytm i program obliczeń przebiegów czasowych wielkości elektrycznych i mechanicznych w układzie: akumulator - rozrusznik samochodowy z bezszczotkowym silnikiem prądu stałego (BLDC) - silnik spalinowy. Opracowany model matematyczny, algorytm i program obliczeń uwzględniają, m.in.: zmienność momentu bezwładności układu korbowego silnika spalinowego, zmienność momentu kompresji i dekompresji gazów w cylindrach oraz zależność momentu tarcia silnika spalinowego od prędkości chwilowej wału korbowego. Obliczono przebiegi czasowe wielkości elektrycznych i mechanicznych w analizowanym układzie.
A mathematical model, algorithm and program for calculations of electrical and mechanical quantities transients in the system: accumulator — starter with brushless direct current motor - combustion engine were developed (Figs 1, 2, 3). The developed mathematical model, computational algorithm and program take account of the combustion engine crankshaft moment of inertia variations as well as the variations of both the compression and decompression torque in the cylinders and the combustion engine friction torque dependence on the instantaneous crankshaft speed. Transients of electrical and mechanical quantities in the analysed system were calculated (Figs 4, 5).

Źródło:

Elektrotechnika i Elektronika; 2006, 25, 2; 129-132
1640-7202

Pojawia się w:

Elektrotechnika i Elektronika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 45.

Tytuł:

A new closed loop speed control strategy for a vector controlled three-phase induction motor drive

Autorzy:

Tripathi, A.
Dey, A.
Dwivedi, B.
Singh, B.
Chandra, D.

Powiązania:

https://bibliotekanauki.pl/articles/262777.pdf

Data publikacji:

2008

Wydawca:

Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

Tematy:

space vector modulation
VSI
induction motor model
transients
steady state value

Opis:

This paper presents a completely mathematical equations based model on control of torque and speed of a three-phase indirect vector controlled VSI fed cage induction motor drive that is controlled through the space vector modulated method. This enables a wide range of acceptability of the model for various values of load and for various types and ratings of induction motors. The uniqueness of the model lies in the fact that the deviations in the torque and speed on sudden application of reference step change in speed values are minimum i.e. when any sudden change in the speed reference is desired, the speed and torque waveforms reveal that the time taken in coming back to their final steady state values is very less and the motor overcomes the perturbation with negligible transients. The same is verified through the simulated results.

Źródło:

Electrical Power Quality and Utilisation. Journal; 2008, 14, 1; 67-72
1896-4672

Pojawia się w:

Electrical Power Quality and Utilisation. Journal

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 46.

Tytuł:

Przebiegi nieustalone prądu i momentu elektromagnetyczneco podczas rozruchu w silnikach indukcyjnych wysokoobrotowych
Transients of current and electromagnetic torque during start-up in high-speed induction motors

Autorzy:

Zielińska, M.J.
Zieliński, W.G.
Zieliński, W.

Powiązania:

https://bibliotekanauki.pl/articles/1373753.pdf

Data publikacji:

2009

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Napędów i Maszyn Elektrycznych Komel

Tematy:

silnik indukcyjny
silnik wysokoobrotowy
rozruch

Opis:

High-speed motors are produced in Poland outside the machine-building industry. Only a few motors, adapted to specific purposes, are manufactured, for example, by plants that produce rolling-element bearings. These motors have found their application in driving high-speed grinders in bearing ring raceway production lines. The properties of motors fed with high-frequency voltage result mainly from the use of a closed slot in the rotor and the high frequency of supply voltage. The use of the closed rotor slot causes strong saturation of the magnetic circuit by the leakage flux around the slot. Taking account of the phenomenon of saturation of the magnetic circuit due to the leakage flux around the closed rotor slots is a complex issue. In the present article, this phenomenon was taken into consideration by introducing into the mathematical model of the motor, derived for a linear magnetic circuit, rotor leakage inductance dependent on rotor current. The relation was determined experimentally.

Źródło:

Maszyny Elektryczne: zeszyty problemowe; 2009, 82; 249-252
0239-3646
2084-5618

Pojawia się w:

Maszyny Elektryczne: zeszyty problemowe

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 47.

Tytuł:

Time and electric energy losses minimization in speed control of induction motors

Autorzy:

Kawecki, L.
Niewierowicz, T.

Powiązania:

https://bibliotekanauki.pl/articles/205536.pdf

Data publikacji:

1999

Wydawca:

Polska Akademia Nauk. Instytut Badań Systemowych PAN

Tematy:

optymalizacja
sterowanie optymalne
zasada maksimum
electric energy losses minimization
electromagnetic transients
induction motors
machine control
optimal control
optimal frequency starting
speed control

Opis:

The paper presents a method for solving the problem of the simultaneous time and electric energy losses minimization during the frequency speed control of induction motors with the electromagnetic transients. To solve this vector optimization problem, the optimization index in the form of linear combination of the scalar indexes is assumed and the Pontryagin maximum principle is used. Examples of solution for two cases of optimal frequency starting of two induction motors are presented.

Źródło:

Control and Cybernetics; 1999, 28, 2; 331-353
0324-8569

Pojawia się w:

Control and Cybernetics

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 48.

Tytuł:

Technical solutions for the control and command system of a Plasma Focus device

Autorzy:

Martin, D. I.
Zoita, V. I.
Cotruta, D. A.
Jianu, A. V.
Ighigeanu, D. I.
Bestea, V. I.

Powiązania:

https://bibliotekanauki.pl/articles/147621.pdf

Data publikacji:

2001

Wydawca:

Instytut Chemii i Techniki Jądrowej

Tematy:

control system
electromagnetic transients
galvanic separation
plasma focus

Opis:

The paper presents the technical problems related to the electrical control and command system (ECC system) for the plasma focus installation IPF-4/5A having the following main parameters: 1 MA plasma current and 40 kJ energy stored at 20 kV charging voltage. The ECC system applies 23 interlocked logical commands, acquires and processes 28 logical states, acquires, processes and displays continuously the main slow-varying signals coming from IPF-4/5A subassemblies. All the plasma focus installation operational sequences are governed by strict hard and soft interlocking using in parallel two control and command systems: one based on PC-control methods and another based on classical control techniques.

Źródło:

Nukleonika; 2001, 46, suppl. 1; 89-91
0029-5922
1508-5791

Pojawia się w:

Nukleonika

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 49.

Tytuł:

Effect of Rho-associated kinase inhibition on actin cytoskeleton structure and calcium response in glioma C6 cells

Autorzy:

Targos, Berenika
Pomorski, Paweł
Krzemiński, Patryk
Barańska, Jolanta
Rędowicz, Maria
Kłopocka, Wanda

Powiązania:

https://bibliotekanauki.pl/articles/1041182.pdf

Data publikacji:

2006

Wydawca:

Polskie Towarzystwo Biochemiczne

Tematy:

glioma C6
actin cytoskeleton
RhoA
ROCK
calcium transients

Opis:

The role of actin cytoskeleton functional state in glioma C6 cell morphology and calcium signaling was investigated through modification of myosin II activity by blocking Rho-associated kinase with the specific inhibitor Y-27632. Treatment of glioma C6 cells with ROCK inhibitor resulted in actin cytoskeleton reorganization and also in the changed shape and distribution of mitochondria. Changes in the distribution of ER, the main calcium store in glioma C6 cells, were not visible. The inhibition of myosin II activity influences the first phase of calcium signaling evoked by agonist, and both phases of thapsigargin-evoked calcium response. We suggest that the observed increase in Ca2+ release from intracellular stores induced by IP3 formation as well as inhibition of SERCA ATPase is at least in part related to severely affected mitochondria. Enhancement of capacitative calcium entry evoked by thapsigargin is probably associated with the reorganization of the acto-myosin II system. ATP-induced calcium response presents no changes in the second phase. We observed that ATP stimulation of Y-27632 pretreated cells leads to immediate morphological rearrangement of glioma C6 cells. It is a consequence of actin cytoskeleton reorganization: formation of stress fibers and relocation of phosphorylated myosin II to actin filaments. It seems that the agonist-evoked strong calcium signal may be sufficient for myosin II activation and the stress fiber organization. This is the first work showing the dependence between the functional state of the acto-myosin II system and calcium signaling stressing the reversible character of this relationship.

Źródło:

Acta Biochimica Polonica; 2006, 53, 4; 825-831
0001-527X

Pojawia się w:

Acta Biochimica Polonica

Dostawca treści:

Biblioteka Nauki

/5

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Skocz do pozycji: 50.

Tytuł:

Program PSCAD/EMTDC jako wygodne narzędzie do modelowania linii napowietrznych
Modelling of Overhead Lines by the PSCAD/EMTDC

Autorzy:

Smolarczyk, A.
Chmielak, W.

Powiązania:

https://bibliotekanauki.pl/articles/158669.pdf

Data publikacji:

2016

Wydawca:

Sieć Badawcza Łukasiewicz - Instytut Elektrotechniki

Tematy:

linie napowietrzne
stany przejściowe
modelowanie
PSCAD/EMTDC
overhead lines
transients in power systems
power system modelling
PSCAD/EMTDC software

Opis:

W artykule opisano jeden z programów do symulacji zjawisk dynamicznych występujących w systemie elektroenergetycznym. Program o nazwie PSCAD/EMTDC jest powszechnie używany do modelowania fragmentów systemu elektroenergetycznego i zjawisk w nich występujących. Przedstawiono dostępne w programie modele linii napowietrznych, które mogą zostać wykorzystane do modelowania takich sytuacji jak stany łączeniowe (załączenia, wyłączenia) linii, zwarcia w linii. W programie linie napowietrzne można zamodelować ręcznie za pomocą elementów pasywnych typu R, L, C, z wykorzystaniem gotowych czwórników typu PI, za pomocą gotowych modeli typu Bergeron Model, Frequency Dependent (Mode) Model, Frequency Dependent (Phase) Model. Pokazano przykładowy sposób zamodelowania linii WN 110 kV z wykorzystaniem słupów kratowych typu B2 za pomocą modelu typu Frequency Dependent (Phase) Model.
The article describes one of the programs for the simulation of dynamic phenomena occurring in the power system. The program called PSCAD/EMTDC is commonly used to model the parts of the power system and phenomena occurring in them. The models of the overhead lines that can be used for modelling situations such as switching states of the line, short-circuit line have been presented. Overhead lines can be manually modelled using passive R, L, C elements by using prepared PI section elements, using prepared Bergeron Model, Frequency Dependent (Mode) Model, Frequency Dependent (Phase) Model. It was shown how to model a high-voltage line 110 kV with the use of type B2 towers by the Frequency Dependent (Phase) Model.

Źródło:

Prace Instytutu Elektrotechniki; 2016, 272; 31-48
0032-6216

Pojawia się w:

Prace Instytutu Elektrotechniki

Dostawca treści:

Biblioteka Nauki

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