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1

Small-signal transmittances of the non-ideal flyback switch-mode DC–DC converter

Bączek Maciej, Janke Włodzimierz, Kraśniewski Jarosław

Archives of Electrical Engineering

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2024

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Vol. 73, nr 1

1--15

EN

Small-signal transmittances of the power stage of a flyback converter in continuous conduction mode are derived on the averaged model obtained by the separation of variables approach. The precise knowledge of these transmittances is necessary in the design process of the converter control circuit. Apart from mathematical formulas for transmittances, the numerical calculations of the frequency dependencies of the transmittances for the assumed set of the converter parameters are presented with the parasitic resistances of components taken into account. The results of the calculations are compared with the measurements performed on the laboratory model of the converter and a good consistency is observed. It is concluded, that the results of the paper may be useful in the designing process of a control circuit of the flyback converter.

2

Closed loop voltage mode controlled high step-down/step-up positive output buck–boost converter

Udumula Ramanjaneya Reddy, Hanumandla Deepika, Bellapu Vijayalakshmi

Journal of Power Technologies

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2020

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Vol. 100, nr 3

255--262

EN

This work presents the positive output buck-boost (POBB) converter with single loop control and simple converter structure. The presented POBB converter achieves the square of the high step-down/step-up voltage conversion gain as compared with the traditional buck-boost (TBB) converter and also the output voltage polarity is positive. These advanced features facilitate work in a wider range of high-step-down/step-up positive output converters. In the high gain POBB converter the two controlled power switches are operated synchronously. The converter is designed to operate in continuous current mode (CCM), one in switch-on mode, during which the two inductors are energized and two capacitors are discharged, and the later one in switch-off mode, during which the two inductorsare deenergized and two capacitors are charged. The operating principles and the steady-state analysis of high step-don/ step-up POBB converter operating in CCM are presented in detail. Further, a closed loop voltage mode control (VMC) is designed and simulated to study the line and load regulations of POBB converter in both high step-down (buck mode) and high step-up (boost modes) respectively. Theoretical analysis and predictions of the closed loop VMC POBB converter have been validated using MATLAB/Simulink platform.

3

Dynamiczne wyznaczanie przegrzania stali za pomocą kontrolnego pomiaru temperatury likwidusu oraz ciągłego pomiaru temperatury stali w kadzi pośredniej maszyny COS

Węgrzyn Wojciech, Pieprzyca Jacek

Hutnik, Wiadomości Hutnicze

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2020

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Vol. 87, nr 6

160--167

PL

W artykule omówiono zastosowaną w praktyce metodologię dynamicznego wyznaczania przegrzania stali oraz jej wpływ na zwiększenie precyzji sterowania procesem ciągłego odlewania stali na maszynie COS. Przeprowadzono również analizę porównawczą metody alternatywnej kontrolnego pomiaru temperatury stali w kadzi pośredniej z wykorzystaniem przykładowych opomiarowanych sekwencji. Wskazano na potencjalne zagrożenia wynikające z bazowania podczas sekwencji ciągłego odlewania na pomiarze kontrolnym w porównaniu do pomiaru ciągłego oraz różnice występujące pomiędzy temperaturą likwidusu liczoną wg różnych modeli matematycznych i mierzoną czujnikiem zanurzeniowym.

EN

This article briefly reviews dynamic superheat of steel determination in practice and presents the outcomes for more accurate continuous casting process control. The competitive methods have been evaluated using casting sequences with both continuous and dip steel temperature measurement. The potential threats of operating a caster based on dip temperature only in comparison with continuous measurement have been indicated along with the differences in liquidus temperatures determined by various mathematical models and the physically measured value.

4

Large-signal input characteristics of selected DC–DC switching converters. Part I. Continuous conduction mode

Janke Włodzimierz, Bączek Maciej, Kraśniewski Jarosław, Walczak Marcin

Archives of Electrical Engineering

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2020

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Vol. 69, nr 3

739--750

EN

Large-signal input characteristics of three DC–DC converter types: buck, boost and flyback working in the continuous conduction mode (CCM), obtained by simulations and measurements are investigated. The results of investigations are presented in the form of the analytical formulas and the exemplary results of the measurements and two forms of simulations: based on the full description of the converter components and on the averaged models. The parasitic resistances of the converter components are included in the simulations and their influence on the simulation results is discussed.

5

Large signal Simulink models of a boost converter in CCM and DCM modes

Błasiński W., Błasiński H.

Przegląd Elektrotechniczny

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2016

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R. 92, nr 3

11--15

EN

This paper presents simulation models of an open loop boost converter. The proposed models are applicable to both; continuous conduction mode CCM and discontinuous conduction mode DCM. We derive two variants of the model, applicable for instantaneous and averaged signal analysis. The proposed models are open loop systems, without control feedback, and they are useful for dynamic states simulations and in alternative control closed loop systems investigations. We implemented the models in Matlab/Simulink and compared the simulated waveforms with oscillograms recorded from a physical DC/DC system.

PL

W artykule przedstawiono modele symulacyjne zasilacza dławikowego podwyższającego napięcie wyjściowe dla sygnałów chwilowych i sygnałów uśrednionych. Modele uwzględniają dwa stany pracy zasilacza, ciągłego i nieciągłego prądu dławika. Modele dotyczą struktury otwartej układu, bez układu sterowania i sprzężeń zwrotnych. Mogą być wykorzystane do badania różnych struktur układów sterowania zasilacza. Przedstawiono struktury modeli z wykorzystaniem programu Matlab/Simulink oraz porównano przebiegi symulacji z przebiegami w układzie rzeczywistym.

6

Small-signal transmittances of DC-DC step-down PWM converter in various operation modes

Janke W.

Archives of Electrical Engineering

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2015

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Vol. 64, nr 3

505--529

EN

Small-signal transmittances: input-to-output and control-to-output of BUCK converter power stage working in CCM or DCM mode are discussed. Ideal converter case and converter with parasitic resistances are considered separately. Derivations of small-signal transmittances, based on different approaches to finding the converter averaged models, are presented and the results are compared. Apart from theoretical considerations, some results of numerical calculations are presented.

7

Comparison of transient states in step-down power converter (BUCK) in continuous and discontinuous conduction mode

Janke W., Walczak M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2014

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Vol. 62, nr 4

773--778

EN

The object of this paper is a step-down (BUCK) power converter working in the continuous conduction mode (CCM) or discontinuous conduction mode (DCM). Two types of transient states in a converter have been analyzed and observed experimentally: slow transients, described by averaged models of a converter and fast transients, in the course of a single switching period. The averaged models of converter working in CCM, presented in various sources are similar, with some differences concerning only the description of parasitic effects. The averaged models for DCM depend on the adopted modeling method. Models obtained by the switch averaging approach are second-order models (containing two reactive elements in equivalent circuit representation). Models obtained by the separation of variables approach are first-order models. The experimental results given in this paper show the first-order type of transients. Another group of experiments concern fast transients in the course of a single switching period. The oscillations of inductor voltage in the part of a switching period are observed for DCM.

8

Wpływ doświetlania lampami sodowymi i led na wybrane parametry wzrostu roślin rabatowych

Treder J., Klamkowski K., Treder W., Puternicki A., Lisak E.

Prace Instytutu Elektrotechniki

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2012

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Z. 256

143-154

PL

Ukorzenione sadzonki roślin rabatowych: fuksji 'Beacon' oraz irezyny 'Shiny Rose' uprawiano zimą w szklarni stosując doświetlanie lampami sodowymi (400 W) i LED (zestaw oświetleniowy DAPLON-plus/2011 skonstruowany w Instytucie Elektrotechniki, emitujący światło w zakresach: niebieskim, czerwonym i bliskiej podczerwieni). Doświetlanie stosowano w godzinach 6-18, wyłączając je, gdy natężenie naturalnego promieniowania docierającego do roślin było wyższe niż 200 W m-2. Rośliny kontrolne uprawiano bez doświetlania. Dla obydwu doświetlanych kombinacji natężenie napromieniowania mierzone na poziomie łanu liści wynosiło 150-190 ?mol m-2 s-1. Wybrane parametry wzrostu roślin (wysokość, rozkrzewienie, świeżą i suchą masę) oceniono po 6 tygodniach wzrostu. Uzyskane wyniki wskazują, że obydwa gatunki doświetlane lampami LED były bardziej zwarte, wytworzyły mniej pędów bocznych oraz miały mniejszą powierzchnię liści. Świeża i sucha masa nadziemnej części irezyny i fuksji była najwyższa w przypadku doświetlania światłem sodowym. Najniższe wartości analizowanych parametrów wykazano w przypadku roślin kontrolnych, niedoświetlanych.

EN

Rooted cuttings of fuchsia 'Beacon' and iresine 'Shiny Rose' were cultivated in greenhouse during winter months (November, December). Supplemental lighting was applied from 6 do 18 using High Pressure Sodium Lamps (HPS, 400 W) or LED lamps (DAPLON-plus/2011, model elaborated in Electrotechnical Institute, Warsaw). Lamps were switched off when natural irradiation was higher than 200 W m-2. Control plants were grown in natural light conditions - without supplemantal lighting. For both treatements with supplemental lighting light intensity on plant canopy was 150-190 ?mol m-2 s-1. The growth parameters (plant height, branching, fresk and dry weight) were evaluated after 6 weeks of cultivation In greenhouse. Obtained results showed that both bedding plants iresine and fuchsia grown with LED lamps were more compact, with shorter side shoots and with lower leaf area. Fresh and dry weight of iresine and fuchia were the highest in conditions with HPS lamps. According to expectations the control plants, grown without supplemental lighting, had significantly shorter stems with less side shoots, the lowest fresh and dry weights and the lowest leaf area. Plants grown with supplemental ligting using HPS and LED lamps,had higer chlorophyll content in leaves (expressed as CCM and SPAD values), comparing to control plants.

9

Influence of CCM, CBC-MAC, CTR and stand-alone encryption on the quality of transmitted data in the high-performance WSN based on Imote2

Rusinek D., Księżopolski B.

Annales Universitatis Mariae Curie-Skłodowska. Sectio AI, Informatica

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2011

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Vol. 11, no. 3

117--127

EN

In this paper we examine the influence of different types of encryption and authentication on the quality of transmitted data in the high-performance WSN based on Imote2. The performance has been tested in the wireless sensor network using Collection Tree Protocol. The examined types and modes of encryption are provided by the hardware of used sensor platforms Intelmote2 and its integrated radio chip CC2420. The presented results can be helpful to choose which cryptographic modules should be implemented according to the acceptable packet loss.

10

Combinatorial discovery approaches accelerate the development of bioresorbable medical implants

Kohn J.

Engineering of Biomaterials

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2009

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Vol. 12, no. 89-91

258--259

11

Modelowanie technologii produkcji kukurydzy uprawianej na CCM

Hołaj J., Zaliwski A. S.

Inżynieria Rolnicza

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2008

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R. 12, nr 2(100)

43-50

PL

W pracy przedstawiono model służący do wyboru korzystnej technologii produkcji kiszonki z rozdrobnionych kolb kukurydzy (CCM). Pozwala on na tworzenie wariantów technologii przez zmianę zabiegów agrotechnicznych. Zmiany zużycia środków obrotowych dają dodatkową możliwość zwiększenia liczby wariantów. Wybór technologii przeprowadza się na podstawie analizy nakładów pracy i kosztów bezpośrednich produkcji kukurydzy na CCM. Znaczącą pozycją w kosztach bezpośrednich produkcji są koszty materiałów, przede wszystkim nawozów. Baza danych modelu obejmuje m.in. odmiany, technologie produkcji i ceny. Obliczane są nakłady pracy, koszty bezpośrednie produkcji i nadwyżka bezpośrednia produkcji. Model użyto do analizy technologii produkcji CCM w kombinacji trzech powierzchni (1 ha, 5 ha i 25 ha) i czterech sposobów nawożenia. Długotrwały efekt ekonomiczny nawożenia analizowano przy pomocy programu ZeaSoft.

EN

A model for selecting a profitable production technology of CCM is presented. The model makes it possible to create technology variants through the change of field operations. The change of working assets gives an additional possibility to multiply the number of variants. The selection of technology is conducted on the basis of the analysis of labour layouts and direct costs of CCM production. A significant item in the direct costs of production is the cost of materials, primarily the cost of fertilisers. The database of the model comprises, among others: varieties, production technologies and prices. The outputs of the model are labour layouts, direct production costs and direct income. The model was used to analyse CCM production technology variants - a combination of three areas (1 ha, 5 ha and 25 ha) and four ways of fertilisation. The multiyear economic effect of fertilization was analysed with the ZeaSoft computer program.