Wyniki wyszukiwania - Biblioteka Nauki

1

Modified Topology and Modulation Technique for Z-Source Neutral-Point Clamped Inverter

100%

Akbari E. , Zishan F.

Power Electronics and Drives

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2022

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tom Vol. 7 (42)

210--226

EN

The impedance network makes it possible to increase and decrease the voltage, which is not available in normal inverters (voltage and current sources).This paper presents a modified topology and modulation technique for a three-phase Modified Z-Source Neutral-Point Clamped (MZS-NPC) inverter. A modulation scheme for the proposed topology is designed based on maximum gain control method to achieve the maximum voltage gain by simple implementation and balancing the neutral point voltage of the dc link. In order to supply the desired voltage to the critical load in an islanded micro-grid, a closed-loop ac voltage controller is realized in fuel cell or photovoltaic applications based on the proposed inverter. The ability to reinforce and validity of topology operations and modulation techniques has been demonstrated by simulation. It should be noted that the simulations are implemented in MATLAB / Simulink software.

2

Three-level modulation techniques to reduce instantaneous common mode voltage in induction machines

100%

Cusidó J. , Luna A. , Busquets S. , Bordonau J. , Rodríguez P. , Romeral L.

Electrical Power Quality and Utilisation. Journal

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2007

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tom Vol. 13, nr 2

33-38

EN

Problems on inverter motor drives such as bearing currents are introduced due to common mode voltages. Different solutions are proposed on literature, for two-level or multilevel inverter. Instantaneous zero common mode voltage by using a three-level inverted could be achieved. This paper proposes a commutation strategy that allows zero common mode voltage by using medium vectors, and also a new representation as a plane on the commutation space is defined which is called zero common mode voltage plane. On this defined plane, every turning vector fulfil this property. Simulations and experimental results clearly show method's efficiency.

3

Modeling and simulation of novel stepped DC coupled quasi Z-Multilevel Inverter for single phase systems

100%

Meenakshi T. , Suthanthira Vanitha N.

Archives of Electrical Engineering

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2016

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tom Vol. 65, nr 3

437--448

EN

This paper presents the modeling and simulation of a novel topology of quasi Z-Multilevel Inverter with stepped DC input. The proposed inverter incorporates a simple switching technique with reduced component count and is aimed at producing boosted multilevel output AC voltage. The inverter consists of two stages and the buck /boost operation is obtained by varying the shoot through period of the pulses obtained by maximum constant boost control with third harmonic injection. With all the advantages of the quasi Z-network, the proposed inverter eliminates the fly back diodes and capacitors present in a conventional Z-Multilevel Inverter. Further the stress on the devices is less which leads to reduction in component value and hence the cost. The novel stepped DC coupled Single Phase quasi Z-Multilevel Inverter is modeled and simulated in the MATLAB – SIMULINK environment and its performance is analyzed for varying input and switching conditions. The voltage and current waveforms across each stage of the inverter is analyzed and the results are presented for different levels of input.

4

Extended T-type inverter

100%

Rąbkowski J. , Kopacz R.

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2018

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tom Vol. 3 (38), No. 1

55--64

EN

This paper presents a new concept for a power electronic converter – the extended T-type (eT) inverter, which is a combination of a three-phase inverter and a three-level direct current (dc)/dc converter. The novel converter shows better performance than a comparable system composed of two converters: a T-type inverter and a boost converter. At first, the three-level dc/dc converter is able to boost the input voltage but also affects the neutral point potential. The operation principles of the eT inverter are explained and a simulation study of the SiC-based 6 kVA system is presented in this paper. Presented results show a serious reduction of the DC-link capacitors and the input inductor. Furthermore, suitable SiC power semiconductor devices are selected and power losses are estimated using Saber software in reference to a comparative T-type inverter. According to the simulations, the 50 kHz/6 kVA inverter feed from the low voltage (250 V) shows <2.5% of power losses in the suggested SiC metal oxide–semiconductor field-effect transistors (MOSFETs) and Schottky diodes. Finally, a 6 kVA laboratory model was designed, built and tested. Conducted measurements show that despite low capacitance (2 × 30 μF/450 V), the neutral point potential is balanced, and the observed efficiency of the inverter is around 96%.

5

Degree of Fault Tolerance as a Comprehensive Parameter for Reliability Evaluation of Fault Tolerant Electric Traction Drives

88%

Bolvashenkov I. , Herzog H. G.

Transactions on Environment and Electrical Engineering

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2016

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tom Vol. 1, No. 3

50--61

EN

This paper describes a new approach and methodology of quantitative assessment of the fault tolerance of electric power drive consisting of the multi-phase traction electric motor and multilevel electric inverter. It is suggested to consider such traction drive as a system with several degraded states. As a comprehensive parameter for evaluating of the fault tolerance, it is proposed to use the criterion of degree of the fault tolerance. For the approbation of the proposed method, the authors carried out research and obtained results of its practical application for evaluating the fault tolerance of the power train of an electrical helicopter.

6

Single-source three-phase switched-capacitor-based MLI

88%

Jena K. , Gupta K. K. , Bhatnagar P. , Jain S. K. , Stala R. , Waradzyn Z. , Piróg S. , Penczek A. , Mondzik A. , Skała A.

Power Electronics and Drives

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2022

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tom Vol. 7 (42)

197--209

EN

This article proposes a novel three-phase inverter based on the concept of switched capacitors (SCs), which uses a single DC source. A three-phase, seven-level line-to-line output voltage waveform is synthesised by the proposed topology, which includes eight switches, two capacitors, and one diode per phase leg. The proposed topology offers advantages in terms of inherent voltage gain, lower voltage stresses on power switches, and a reduced number of switching components. Additionally, the switched capacitors are self-balanced, thereby eliminating the need for a separate balancing circuit. The proposed structure and its operating principle, the self-balancing mechanism of the capacitors, and the control strategy are all thoroughly explained in the article. The proposed topology has also been compared with some recent SC topologies. Lastly, the proposed topology has been shown to be feasible through simulation and experimentation.

7

Integrated Model Predictive Control of a Single-Phase Multilevel T-type Converter for a Photovoltaic Grid Connected System under Failure Conditions

75%

Boudja W. , Barra K.

Power Electronics and Drives

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2023

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tom Vol. 8 (43)

142-164

EN

The article presents two contributions: the first is an optimised control structure for photovoltaic grid connected systems (PVGCSs). The power chain is composed of two cascaded power converters, namely, a boost converter and a five-level T-type multilevel converter. Traditionally, each power converter is controlled by a separate mode control (SMC) from the other, which is computationally intensive since each converter requires its own control system, which is not practical. The suggested control, called integrated finite set model predictive control (IFS-MPC), allows controlling cascaded converters at the same time in one stage, instead of controlling them separately. Consequently, the overall implementation system is widely reduced. The second contribution of the article is a modified IFS-MPC called modified integrated finite set-model predictive control (M-IFS-MPC), which ensures the correct functioning of the grid-tied PV system under certain faults in converter components. Indeed, when one of the DC-link capacitors fails or when one of the auxiliary switches breaks down, by selecting an appropriate choice of the DC-link capacitors’ voltage reference, the proposed design allows a normal operation without intervention on the power circuit.

8

Stability analysis and efficiency improvement of IPFC using latest PR controller

75%

Gurijala S. B. , Kishore D. R. , Nittala R. , Godala R. R.

Archives of Electrical Engineering

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2021

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tom Vol. 70, nr 3

615--630

EN

The deviation from the ideal waveformcauses disturbances and failure of end-user load equipment. Power traveling a long distance from the generation plant to the end-user leads to deterioration of its quality, and the intensive utilization of power leads to serious issues in the grid resulting in power quality problems. To make the system effective and able to meet modern requirements, flexible AC transmission system (FACTS) devices should be installed into the grid. The interline power flow controller (IPFC) is the latest FACTS device, which compensates for both active and reactive power among multi-line systems. The converters used in the IPFC are crucial as they can be adjusted to regulate the power flow among the lines. This paper proposes a cascaded IPFC with hysteresis and proportional resonant voltage controllers. Some main drawbacks of controllers like steady-state errors and reference tracking of converters can be easily achieved by the PR controller, which makes the system efficient and can be used for a wide range of grid applications. Hysteresis and PR controllers are explained in detail in the following sections. A comparative analysis is carried out among control algorithms to choose the suitable controller which maintains stability in the system.

9

Implementation of the PWM gating and IGBT protection scheme for the grid-connected multilevel inverter applications

75%

Xu L. , Han Y. , Chen C. , Pan J. , Yao G. , Khan M. , Zhou L.

Przegląd Elektrotechniczny

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2010

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tom R. 86, nr 7

360-365

EN

A novel approach for implementation of the PWM gating and IGBT protection scheme is proposed for the grid-connected cascaded Hbridge multilevel inverter applications. The controller architecture based on the master/slave configuration is presented, with the main focus on the implementation issues of the bottom FPGA controller and IGBT drivers. The gating strategies and protection scheme are presented by introducing the hardware circuitry and the VHDL codes. Experimental results based on three H-bridge modules are provided for verification.

PL

Zaproponowano nową możliwość wykorzystania bramkowania PWM i protekcji IGBT w sieciowo połączonej kaskadzie wielopoziomowych przekształtników. Architektura kontrolera bazowała na konfiguracji master/slave. Strategia bramkowania i schemat zabezpieczeń zostały sprawdzone sprzętowo. Wyniki eksperymentu z trzema mostkowymi modułami typu H potwierdziły założenia. (Zastosowanie bramkowania PWM i zabezpieczenia IGBT w kratowo połączonym wielopoziomowym przekształtniku.

10

Wpływ algorytmów sterowania na właściwości zmodyfikowanej kaskady wielopoziomowego falownika napięcia

75%

Kot E.

Przegląd Elektrotechniczny

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2006

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tom R. 82, nr 7-8

105-108

PL

W artykule przedstawiono właściwości zmodyfikowanej kaskady wielopoziomowego falownika napięcia przy zastosowaniu różnych algorytmów sterowania. Szczególną uwagę zwrócono na porównanie przebiegów czasowych, wyjściowych napięć fazowych falownika, uzyskanych przy pomocy pakietu symulacyjnego PSpice oraz widm amplitudowych napięcia fazowego falownika obliczonych na podstawie podwójnego szeregu Fouriera. Pokazano przykład zbieżności wyników uzyskanych na drodze analitycznej z wynikami modelu eksperymentalnego.

EN

In this paper some properties of the modified cascade multilevel inverter for the high voltage, high power inverter applications have been presented. Simulation results of the output voltage of the inverter for five controls algorithms have been proposed and compared. Some experimental results have been presented, to confirm the results of theoretical analysis.

11

The conception of the use of multi-level inverters in the shipping shaft generator systems of high power

75%

Tarnapowicz D.

Zeszyty Naukowe / Akademia Morska w Szczecinie

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2010

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tom nr 22 (94)

67-70

EN

The fundamental problem of using the shaft generators of high power in the shipping systems is bound up with the stability of frequency. Electronic systems used nowadays are based on the thyristor inverters which entails vices of such solutions. The article presents the conception of the use of multi-level inverters built on the basis of fully controllable valves (transistors IGBT).This solution eliminates the defects of thyristor inverters.

PL

Zasadniczy problem stosowania w systemach okrętowych prądnic wałowych dużej mocy związany jest ze stabilizacją częstotliwości. Stosowane obecnie układy energoelektroniczne opierają się na wykorzystaniu falowników tyrystorowych, które implikują wady takich rozwiązań. W artykule przedstawiono koncepcję wykorzystania falowników wielopoziomowych, zbudowanych w oparciu o zawory w pełni sterowalne (tranzystory IGBT), które pozbawione są wad falowników tyrystorowych.

12

Analysis, simulation and experimental validation of high frequency DC/AC multilevel inverter

75%

Toubal Maamar A. E. , Helaimi M. h. , Taleb R.

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tom R. 96, nr 8

16--19

EN

In this study, the analysis, simulation and realization of direct current to alternating current multilevel inverter are discussed. Inverter operation with the high-frequency mode is evaluated and tested for the validation of the topology. This inverter type will be used in an induction heating system or other industrial applications need high-frequency, periodic and alternating signals. The control signals of electronic switches are implemented via an open-source board, Arduino, composed of an Atmega2560 microcontroller. Simulation with MATLAB/Simulink environments and experimental results are presented, comparatively, for a comparison.

PL

W artykule zaprezentowano symulację, analizę I eksperymentalną weryfikację przekształtnika. DC/AC. Ten typ przekształtnika może być zastosowany w nagrzewaniu elektrycznym lub innych zastosowaniach wymagających prądu wcz.

13

Uśredniony model okrętowego kompensatora udarów mocy SN budowanego na podstawie czteropoziomowego falownika napięcia z diodami poziomującymi

63%

Grabarek M.

Przegląd Elektrotechniczny

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2016

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tom R. 92, nr 3

164--168

PL

Artykuł przedstawia uśredniony model kompensatora udarów mocy, budowany na podstawie falownika czteropoziomowego typu Diode Clamped i zasobnika superkondensatorowego, z przeznaczeniem do zastosowania w systemach elektroenergetycznych jednostek morskich. Opracowany model jest dedykowany do zadań związanych z syntezą i weryfikacją nadrzędnych algorytmów sterowania oraz symulacji izolowanych systemów elektroenergetycznych.

EN

Paper presents continuous average model of power surge compensator, based on a four level diode clamped inverter. The model is suitable for synthesis of control algorithms, as well for simulation of ship’s power conditioning unit designed to an active power surge smoothing in isolated power plants.

14

Multilevel neural network DTC with balancing strategy of sensorless DSSM using extended Kalman filter

63%

Elakhdar B. , Said B. , Sadouni R.

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tom Vol. 101, nr 2

96--104

EN

This paper presents direct torque control based on artificial neural networks of a double star synchronous machine without mechanical speed and stator ux linkage sensors. The estimation is performed using the extended Kalman filter, which is known for its ability to process noisy discrete measurements. The proposed approach consists of replacing the switching tables with one artificial neural network controller. The output vector of the artificial neural network controller is directed to a multilevel switching table to decide which reference vector should be applied to control the two five-level diode-clamped inverters. This inverter topology has the inherent problem of DC-link capacitor voltage variations. Multilevel direct torque control based on a neural network with balancing strategy is proposed to suppress the unbalance of DC-link capacitor voltages. The simulation results presented in this paper highlight the improvements offered by the proposed control method based on the extended Kalman filter under various operating conditions.

15

High performance of multilevel inverter reduced switches for a photovoltaic system

63%

Mohammed L. A. , Hussein T. A. , Sadoon A. T.

Przegląd Elektrotechniczny

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2022

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tom R. 98, nr 8

14--18

EN

In this paper, optimum switching angles are chosen from slime moiled algorithm (SMA), Artificial Bee Colony (ABC), Genetic algorithms (GA), Whale optimization algorithm (WOA), and Gray wolf algorithm (GWO). These angles are selected according to the lowest total harmonic distortion of output load voltage from reduced switches multilevel inverter. These algorithms are working together in a hybrid seduced to solve the nonlinear equation of switching angles determination. A 25-level inverter fed by isolated unequal PV panel as DC sources with reduced switches and sources is chosen for this study. Theoretical analysis and Simulation are accomplished using Matlab/Simulink for 25 level reduced switches multilevel inverter. The simulated results validated the practical outcomes.

PL

W niniejszym artykule optymalne kąty przełączania zostały wybrane spośród algorytmu śluzowatego (SMA), sztucznej kolonii pszczół (ABC), algorytmów genetycznych (GA), algorytmu optymalizacji wielorybów (WOA) i algorytmu szarego wilka (GWO). Kąty te są dobierane zgodnie z najniższymi całkowitymi zniekształceniami harmonicznymi napięcia obciążenia wyjściowego ze zredukowanych przełączników wielopoziomowych falowników. Algorytmy te współpracują ze sobą w hybrydzie, której celem jest rozwiązanie nieliniowego równania wyznaczania kątów przełączania. Do tego badania wybrano 25-poziomowy falownik zasilany przez izolowany nierówny panel fotowoltaiczny jako źródła prądu stałego o zredukowanych przełącznikach i źródłach. Analiza teoretyczna i symulacja są realizowane przy użyciu Matlab/Simulink dla 25 przełączników o zredukowanych poziomach wielopoziomowego falownika. Symulowane wyniki potwierdziły praktyczne wyniki.

16

Nowa koncepcja układu kondycjonowania energii elektrycznej w elektroenergetycznej sieci okrętowej

63%

Hashad M.

Przegląd Elektrotechniczny

|

2006

|

tom R. 82, nr 7-8

69-73

PL

W artykule przedstawiono nową koncepcję poprawy jakości energii elektrycznej w elektroenergetycznej sieci okrętowej poprzez poprawę jakości napięcia zasilającego. Idea tejże poprawy polega na "usztywnianiu" miękkiej sieci, jaką jest elektroenergetyczna sieć okrętowa. Wahania napięcia zasilającego można zmniejszyć stosując wielopoziomowy falownik napięcia, jako równoległe źródło napięciowe o stosunkowo małej impedancji wewnętrznej, jednocześnie zmniejszając wahania częstotliwości wynikające z załączenia dużych odbiorników.

EN

Ship shaft generators system- in contrary to wind generators- is not improved dynamically in last years. The main goal for wind generators is to delivery electrical energy to the electrical system however for ship shaft generators is quite different - to convert and transmit electrical energy from the main diesel motor. This goal is not as attractive as to generate energy. The new proposed concept based on applying multilevel inverter into ship electrical conditioning system to improve quality of electrical energy. The topology of multilevel inverter based on orthogonal vectors has been described and presented as well.

17

Kompensacja napięcia zaburzeń na wyjściu wielopoziomowych falowników napięcia

63%

Smoleński R. , Kempski A.

Przegląd Elektrotechniczny

|

2006

|

tom R. 82, nr 7-8

86-89

PL

W pracy przedstawiono analizę dotyczącą warunków pracy elementów indukcyjnych stosowanych w pasywnym filtrze napięcia zaburzeń wspólnych (CM). Zaproponowano teoretyczną metodę analizy, umożliwiającą określenie najgorszego - z punktu widzenia możliwości nasycania się dławika - przypadku, przy którym prąd magnesujący osiąga maksymalną wartość. Wykorzystano w tym celu przebieg napięcia CM na wyjściu N-poziomowego falownika. Pozawala to na sformułowanie wymagań projektowych, dotyczących parametrów dławika.

EN

This paper presents an approach to the problem of a magnetic saturation of CM chokes that accompanies the method of passive compensation of a common mode (CM) voltage in an inverter drive system. The theoretical analysis and experimental results show that the problem with magnetic saturation becomes less important in multilevel inverter drives, thus permitting a reduction of size, weight and cost of inductive components of filters in such drives.

18

Comparison of multilevel inverters with T-type inverter

63%

Lakshmi G. S. , Sreeshobha E. , Kumar S. N.

Przegląd Elektrotechniczny

|

2023

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tom R. 99, nr 6

14--18

EN

This paper provides a comparison analysis of various types of multilevel inverters with T-Type inverters. The primary goal of this work is to examine the operation of T-type multilevel inverters with various multilevel inverters. The inverter used in our paper is based on a multilayer bidirectional DC-DC converter that can be used in EV applications. The proposed design incorporates two power switches as well as an additional capacitor to balance the currents of the multilayer T-type (MLI) capacitor over the course of a drive pattern or during fault conditions. Due to the highfrequency cycle-by-cycle current security between CN and CP, the large electrolytic capacitors in T-type MLI have been replaced with longer-lasting film capacitors in this design. Because of this, the dimensions and weight of the converter would be reduced by 20%.

PL

Artykuł zawiera analizę porównawczą różnych typów falowników wielopoziomowych z falownikami typu T. Podstawowym celem tej pracy jest zbadanie pracy falowników wielopoziomowych typu T z różnymi falownikami wielopoziomowymi. Falownik zastosowany w naszym artykule oparty jest na wielowarstwowej dwukierunkowej przetwornicy DC-DC, która może być wykorzystana w aplikacjach EV. Proponowany projekt obejmuje dwa przełączniki zasilania, a także dodatkowy kondensator do równoważenia prądów wielowarstwowego kondensatora typu T (MLI) w trakcie wzorca napędu lub w warunkach awarii. Ze względu na zabezpieczenie prądowe cykl po cyklu o wysokiej częstotliwości między CN i CP, duże kondensatory elektrolityczne w MLI typu T zostały w tym projekcie zastąpione trwalszymi kondensatorami foliowymi. Dzięki temu wymiary i waga konwertera zostałyby zmniejszone o 20%.

19

Power balancing control strategies for the cascaded H-bridge multilevel DSTATCOM

63%

Han Y. , Xu L. , Mansoor Khan M. , Chen C.

Przegląd Elektrotechniczny

|

2011

|

tom R. 87, nr 2

212-219

EN

This paper proposes a novel power balancing control scheme for the cascaded H-bridge (CHB) DSTATCOM. The principle of the carrier phase-shifted pulse-width modulation (CPS-PWM) and the mathematical model of the CHB-DSTATCOM are presented. The power balancing mechanism and the stable control region are analyzed using the phasorial diagram representation. The current loop controller is designed by using root locus approach, and the dc-link voltage balancing controller is synthesized based on the devised power balancing mechanism. The simulation results obtained from the alternative transient program (ATP) are presented and evaluated. The validity and effectiveness of the control scheme is confirmed by the simulation and experimental results.

PL

Zapropnowano nową metodę równoważenia mocy w kaskadowym H-mostkowym SSTATCOM. Zaprezentowano zasadę modulacji przesunięcia fazowego i szerokości impulsu CPS-PWM i model matematyczny CHB-DSTATCOM. Równoważenie mocy i analiza stabilnego sterowania zostały przeprowadzone przy użyciu diagramu fazowego. Kontroler pętli prądowej został zaprojektowany przy użyciu obwiedni pierwiastkowej a kontroler napięcia dc-link jest syntetyzowany na podstawie balansu mocy. Przedstawiono symulowane rezultaty. Symulacje i eksperymenty potwierdziły skuteczność metody.

20

Comparative analysis of different inverters and controllers to investigate performance of electrosurgical generators under variable tissue impedance

63%

Mahdi A. J. , Abood Saber H. , Mohammed Ridha A. , Mohammed M. J.

Acta Innovations

|

2023

|

tom no. 48

61--74

EN

Electrosurgical generators (ESGs) are currently the most widely used surgical technology for clinical operations. The main disadvantage of ESGs is their output power is irregular due to the variable tissue impedance. The heat dissipation caused by the high amount of thermal energy generated leads to medical complications for both patient and surgeon. In this research, various inverter topologies and power controllers are investigated to specify the best structure that ensures best performance. The type of inverter topologies investigated are three level and five level, while the PID structures investigated are integer order (IO-PID) and fractional order (FO-PID). The simulation results indicate that FO-PID with five level inverters is better than IO-PID with three level inverters in terms of minimum heat dissipation rate and THD of the output voltage and current.