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1
Content available remote A home energy management algorithm in demand response events for household peak load reduction
Ahmed M. S., Mohamed A., Homod R. Z., Shreef H.
Przegląd Elektrotechniczny
|
2017
|
R. 93, nr 3
197--200
EN
In the last decades, home energy consumption has increased significantly due to increasing load demand in the residential sector. This paper presents a home energy management (HEM) algorithm to manage the home appliances in a house during a demand response (DR) event. The developed algorithm considers load appliances according to customer preference setting, priority of appliance, and comfortable lifestyle that can be changed at any given time and performs DR at appliance level. The load models are developed based on the operational and physical characteristics for the purpose of DR strategies. Appropriate residential load models are required to support the DR strategies and therefore air conditioner, water heater, electric vehicle and washing machine are chosen as the loads. The proposed HEM algorithm is shown to be effective in managing power consumption at appliances level and can maintain the total household power consumption below its demand limit (DL) without affecting the comfort level.
PL
W artykule predstawiono algorytm do zarządzania konsumpcja energii w gospodarstwach domowych. Algorytm zarządza enegią przy założonym poziomie dopuszczalnego limitu I bazuje na charakterystykach urządzeń podłączonych do sieci.
2
Content available remote Gravitational search optimization approach to improve fuzzy logic speed controller for induction motor drive
Ali J. A., Hannan M. A., Mohamed A.
Przegląd Elektrotechniczny
|
2016
|
R. 92, nr 8
200--205
EN
Fuzzy logic controller (FLC) is very useful for controlling speed and torque variables in the three-phase induction motor (TIM) operation. However, the conventional FLC has the exhaustive traditional trial and error procedure in obtaining membership functions (MFs). This paper presents an adaptive FLC design technique for TIM using a gravitational search algorithm (GSA) optimization technique. This technique provides the numerical values to limit the error and change in error of the MFs based on the evaluation results of the objective function formulated by the GSA. The root mean square error (RMSE) of the speed response is used as a fitness function. An optimal GSA- based FLC (GSAF) fitness function is also employed to tune and minimize the RMSE for improving the performance of the TIM in terms of changes speed and torque. Space vector pulse width modulation (SVPWM) technique is utilized to generate signals via voltage/frequency control strategy for variable frequency inverter. Results obtained from the GSAF are compared with those obtained through particle swarm optimization (PSO) to validate the developed controller. The robustness of the GSAF is better than that of the PSO controller in all tested cases in terms of damping capability and transient response under different load and speed.
PL
W artykule zaprezentowano adaptacyjny sterownik typu fuzzy logic przeznaczony do trójfazowego silnika indukcyjnego wykorzystujący algorytm optymalizacyjny badania grawitacyjnego. Jako funkcję fitness użyto błąd rms odpowiedzi prędkości. Do zasilania silnika wykorzystano metodę modulacji szerokości impulsu.
3
Content available remote Event-based S-transform approach for nonintrusive load monitoring
Khalid K., Mohamed A., Shareef H., Sabeeh M.
Przegląd Elektrotechniczny
|
2016
|
R. 92, nr 5
194--198
EN
In this study, a nonintrusive load monitoring system is developed by analyzing the power signal obtained from a single point of power meter installation to detect ON/OFF load activities. A mathematically designed model with backpropagation neural network is utilized in load pattern recognition to decompose the load operation. Leveraging its unique load signature profile, the S-transform approach is employed to extract the features from the aggregate power signal and analyze the detection of load start-up transient from signal processing. To improve the accuracy of load identification for unknown data, the power factor is used as an additive feature with 99.32% load recognition accuracy.
PL
W artykule analizowany jest system monitorowania obciążenia sieci. Wykorzystano sieć neuronową do rozpoznawania rodzaju Transformata S jest użyta do ekstrakcji danych z sygnału mocy. Dodatkowo do identyfikacji obciążenia użyto współczynnik mocy.
4
Content available remote Static Voltage Stability Analysis in a Distribution System with High Penetration of Photovoltaic Generation
Kamaruzzaman Z. A., Mohamed A.
Przegląd Elektrotechniczny
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2015
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R. 91, nr 8
113--117
PL
W artykule analizowany jest wpływ podłączenia systemu fotowoltaicznego na na stabilność napięcia w radialnym systemie energetycznym IEEE 69. Analizowane są zależność P-V oraz indeks stabilności napięciowej IVSI. Podłączenie systemu fotowoltaicznego poprawia margines obciążenia sieci.
EN
This paper analyses the effect of grid-connected PV systems on static voltage stability using the IEEE 69 radial distribution system. The effect of integrating PV generators into power systems with higher PV penetration level and multiple numbers of PV generators is analyzed using PV curve and improved voltage stability index (IVSI). The P-V curve data show that grid-connected PV systems improve loading margin and voltage magnitude. The IVSI gives a positive output because systems with integrated PV generators reach the voltage collapse point.
5
Content available remote Rule-based Fuzzy and V/f Control for Induction Motor Speed Responses Using SVPWM Switching Technique
Ali J. A, Hannan M. A., Mohamed A.
Przegląd Elektrotechniczny
|
2015
|
R. 91, nr 3
133-136
EN
This paper describes the development of a three-phase induction motor (TIM) drive speed controller. A rule-based fuzzy logic controller (FLC) is developed for TIM speed control in non-linear systems. Speed control applications are tested by conducting simulations under different operating conditions. To achieve reliable TIM operation, the space vector pulse width modulation (SVPWM) scheme is used to generate gate signals for the three-phase, two-level inverter. The SVPWM technique demonstrates excellent performance in TIM speed control. The scalar control (V/f control), which is inexpensive, simple to implement in hardware, and applicable to medium- and high-speed rated TIM applications, is used to control the developed TIM. Results show that the implementation of rule-based fuzzy with V/f control and the SVPWM technique for TIM speed control provides superior performance, which is sufficiently robust and intelligent for real-time applications.
PL
Opisano nową metodę sterowania prędkością trójfazowego silnika indukcyjnego. Wykorzystano sterownik bazujący na logice rozmytej umożliwiający sterowanie w systemach nieliniowych. Do bramkowania sygnału dwupoziomowego przekształtnika wykorzystano wektorowa modulację szerokości impulsu SVPWM. Zastosowano też skalarny przetwornik V/f.
6
Content available remote Performance evaluation modeling a Microelectromechanical system based Finite Element piezoelectric Shear Actuated Beam
Sarker M. R., Mohamed A., Mohamed R.
Przegląd Elektrotechniczny
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2015
|
R. 91, nr 3
5-8
EN
This paper presents the modeling a Microelectromechanical systems (MEMS) based Piezoelectric shear actuated beam by using COMSOL Multiphysics software of version 4.3a. The overall dimensions model of the beam is of 0.1-m long, 0.03-m width and 0.018-m thickness. For this model the structural mechanics boundary conditions are of the cantilever beam is fixed at its surfaces at x = 0 and that all other surfaces are free. In this model applied, the different materials (i.e., Silicon, Titanium, Barium titanate, Lead zirconate titanate, Material) with voltages between the top and bottom surfaces of the piezoceramic domain (i.e., 15V, 35V) have been analyzed. Firstly, select the Structural Mechanics of the Piezoelectric Devices and analyzed changing the selecting physics. Secondly, defining the Geometry on deflection of sandwiched beam is setting the boundary condition and analyzed changing of the beam. Thirdly, the beam is composed of a 0.001-m thick flexible foam core sandwiched by two 0.002-m thick silicon and titanium layers. In the Fourth step, bend of beam is analyzed by changing both materials of sandwiched beam and mashing of the defection beam is display by changing both thickness and electric potential. Finally, the results of analysis allowed to conclude us to design a piezoelectric shear actuated beam with different ranges and resolutions, under the condition of changing both thickness and material of electrodes gives the optimum deflection of 0.0308-um and 0.0815-um under 15V input voltage with different materials.
PL
W artykule zaprezentowano metodę projektowania układów typu MEMS na przykładzie piezoelektrycznego siłownika. Dla siłownika zaproponowano model numeryczny oraz warunki brzegowe. Przedstawiono obliczenia dla różnych materiałów i różnych konstrukcji.
7
Content available remote Managing the Distributed Generation Units in a Microgrid using a Fuzzy-PI Controller
Salam A. A., Mohamed A., Hannan M. A., Shareef H.
Przegląd Elektrotechniczny
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2015
|
R. 91, nr 10
148-153
EN
A power distribution system with distributed generations can operate as a microgrid under specific conditions. A microgrid can be operated under grid-connected and islanded modes seamlessly without disrupting the loads within the microgrid. This study analyzes the intelligent control of a microgrid with a pulse-width modulation-controlled voltage source inverter. Switching patterns are generated through a fuzzy proportional-integral (PI) controller. This study aims to develop a fuzzy-PI controller and compare its performance with that of a PI controller in controlling the voltage and frequency of a microgrid under disturbances in a Matlab/Simulink environment. Results show that the fuzzy-PI controller has higher capability, precision, and robustness than the PI controller in quickly restoring and stabilizing the microgrid. A simulation experiment is also performed to verify the greater validity and effectiveness of the microgrid equipped with the fuzzy-PI controller than with the PI controller. The developed fuzzy-PI controller can reduce the total harmonic distortion by 0.46%.
PL
W artykule analizowano inteligentne sterowanie mikrosiecią z wykorzystaniem przekształtnika sterowanego metodą modulacji szerokości impulsu. Jako sterownik wykorzystano proporcjonalno całkujący układ z logika rozmytą. Zbadano pracę układu w sieci z zakłóceniami. Stwierdzono znaczące przewagi kontrolera pracującego z logika rozmytą w porównaniu do układów konwencjonalnvch.
8
Content available remote Effect of grid-connected photovoltaic systems on static and dynamic voltage stability with analysis techniques – a review
Kamaruzzaman Z. A., Mohamed A., Shareef H.
Przegląd Elektrotechniczny
|
2015
|
R. 91, nr 6
134-138
EN
This paper presents an overview on the effect of grid-connected photovoltaic (PV) system on static and dynamic voltage stability and discusses the analysis techniques used to quantify the effect. A review on the published works showed that the PV system design, PV parameters and the distinct design of power system network affect system voltage stability. Furthermore, a discussion is also made on the optimization techniques used for determining optimum PV placement and sizing for the purpose of improving voltage stability.
PL
W artykule dokonano przeglądu metod analizy wpływu dołączenia systemu fotowoltaicznego na właściwości statyczne i dynamiczne sieci. Odpowiedni projekt wpływa na stabilność napięciową. Analizowano też metody optymalizacji położenia systemu.
9
Content available remote A Review of Techniques for Optimal Placement and Sizing of Electric Vehicle Charging Stations
Islam M. M., Shareef H., Mohamed A.
Przegląd Elektrotechniczny
|
2015
|
R. 91, nr 8
122-126
EN
Fossil fuel depletion and greenhouse gas emission from the burning of fossil fuels motivates policymakers to find an alternative road transport system. Electric vehicles (EVs) are considered as one of the best solutions in road transportation system as EVs can reduce the dependence on fossil fuel and diminish transportation-related emissions from carbon dioxide emission and other pollutants. The key issue in this system is recharging the EV batteries before they are exhausted. Thus, charging stations (CS) should be carefully located to ensure that EV users can access the stations within their driving range. This study represents a survey of the literature focused on the numerous optimization techniques employed from the last decade to determine the optimal EVCS placement and sizing problems.
PL
Zasadniczym problemem w rozwoju pojazdów elektrycznych jest zapewnienie nich naładowania przed pełnym rozładowaniem. Dlatego równie ważnym zagadnieniem jest właściwe rozplanowanie lokalizacji stacji ładowania. W artykule analizowane są różne techniki optymalizacji lokalizacji jak i wielkości stacji.
10
Content available remote Utilization of fuel cell energy source for distribution power generation: theory, modeling and review of research work
Zambri N. A., Mohamed A.
Przegląd Elektrotechniczny
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2014
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R. 90, nr 5
189--200
EN
The energy crisis is one of the most critical phenomena happening in today’s world. The depletion of fossil fuels, the rise in oil prices, and the increase in power demand are the main causes of this problem. Concern over environmental conditions and human health make renewable energy one of the most viable alternative solutions to this crisis. Among various types of renewable energy, fuel cell technology shows a great potential in the electrical energy sector for several reasons, such as high efficiency, clean operation, and immunity to the adverse effects of weather conditions. Recent works prove that fuel cell technology is expected to be a better choice for distributed generation purposes. Distributed generation, which is installed near load centers, can moderate the stress of high electricity demand in the mainstream utility grid. This paper presents an overview of fuel cell technology, with emphasis on fuel cell types, characteristics, and applications. The differences among the various fuel cell types and the dynamic models of each type required for simulation are also discussed. Focus is given to the application of fuel cells in a distributed generation system, the requirements of a fuel cell-based generating system, and issues in distributed generation integration. The present study also discusses the power conditioning unit, which is an important component in the fuel cell-based generating system, as well as its control strategy. Discussion is likewise made on the use of suitable energy storage units for the fuel cell distributed generation system, with regard to battery types and storage control. By adding energy storage units to the fuel cell system, the capabilities of the existing generation system can improve system stability performance.
PL
W artykule zaprezentowano przegląd technologii wytwarzania energii z wykorzystaniem ogniw paliwowych koncentrując się na analizie różnych typów i ich zastosowań. Szczególną uwagę zwrócono na zastosowanie ogniw paliwowych w rozproszonych systemach wytwarzania energii. Analizowano też układ kondycjonowania energii oraz jego sterowanie.
11
Content available remote Under Voltage Load Shedding Scheme Using Meta-heuristic Optimization Methods
Verayiah R., Mohamed A., Shareef H., Abidin I. Z.
Przegląd Elektrotechniczny
|
2014
|
R. 90, nr 11
162--168
EN
Load shedding has been extensively studied because of multiple power system failure occurrences worldwide. Reliable techniques are required to provide rapid and precise load shedding to avert voltage collapse in power networks. Meta-heuristic optimization approaches are currently the widely developed methods because of their robustness and flexibility in dealing with complex and non-linear systems. These methods include genetic algorithm, fuzzy logic control, particle swarm optimization, artificial neural network, ant colony optimization, big-bang big-crunch optimization, and many others. This study provides an overview of all the meta-heuristic methods implemented for under voltage load shedding in power systems.
PL
Pozbywanie się obciążenia jest istotne z punktu widzenia możliwego zapadu systemu przesyłu energii. Do tego celu wykorzystuje się optymalizację meta-heurystyczną głównie dzięki odporności i szerokim możliwościom. W skład metody wchodzą: algorytm genetyczny, logika rozmyta, algorytmy mrówkowe, sieci neuronowe. W artykule dokonano przeglądu tych metod.
12
Content available remote Review of Under-voltage Load Shedding Schemes in Power System Operation
Verayiah R., Mohamed A., Shareef H., Zainal Abidin I.
Przegląd Elektrotechniczny
|
2014
|
R. 90, nr 7
99--103
EN
A voltage collapse event is complex and localized in nature, but its effect is extensive. A vital effect of voltage collapse is total system collapse or blackouts, which will result in a significant loss to utility companies. Online monitoring of power system stability has thus become an important factor for electric power utilities. The final resort prevent the occurrence of a voltage collapse incident is the implementation of an undervoltage load shedding (UVLS) scheme. This paper focuses on the introduction of the UVLS scheme and presents an overview of the principles of the UVLS that are crucial to the design of such a protection scheme. This paper also presents the existing industrial practices and other research methods available to date.
PL
W artykule opisano algorytm UVLS (Under Voltage Shedding Schemes) zastosowany do monitorowania stabilności systemu energetycznego I zapobiegania jego zapaściom. Artykuł jest przeglądem metod stosowanych w praktyce oraz prac badawczych w tej dziedzinie.
13
Content available remote Adaptive interval type2 fuzzy hysteresis-band current-controlled active power filter for power quality improvement
Jajarmi H. R. I., Mohamed A., Shareef H., Subiyanto
Przegląd Elektrotechniczny
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2014
|
R. 90, nr 9
140--145
EN
This paper presents a novel adaptive hysteresis current control based on interval type2 fuzzy logic for active power filter to eliminate harmonics and compensate for reactive power. A new method to generate reference compensating current for the fundamental active current component is also proposed using the recursive discrete Fourier transform. The switching frequency of the conventional fixed hysteresis band (HB) control during the fundamental period is varied; thus causing harmonic ripple of the load current. This problem can be solved using adaptive HB control strategy. In this study, a fuzzy logic controller is used for base control because of its advantages over other adaptive HB techniques, such as mathematical simplicity, ease in adding heuristic knowledge, and robust changes in system operating conditions. An interval type2 fuzzy-adaptive HB technique is utilized for the current control to enhance the switching signals produced by the voltage source inverter. Based on the supply voltage and the slope of the reference current, this controller changes the hysteresis bandwidth. To control the DC capacitor voltage, an interval type2 fuzzy logic based controller is developed. Simulation results of the shunt active power filter with an interval type2 fuzzy adaptive HB current controller are examined and compared with the conventional controller. The results verify the effectiveness of the proposed controller in reducing total harmonic distortion from 21.03% to 2.12% and reactive power from 2616 Var to 6.28Var.
PL
Zaprezentowano nową metodę adaptacyjnego sterowanie prądem w celu eliminacji harmonicznych i kompensacji mocy biernej. Wykorzystano aktywny filtr bazujący na logice rozmytej typu 2. Stosuje się adaptacyjne histerezowe sterowanie w celu poprawy sygnału przełączania wytwarzanego przez przekształtnik napięciowy. Sterownik zmienia szerokość histerezy bazując na wartości napięcia zasilaniam i szybkości zmian pradu. Zmniejszono zawartość harm onicznych z 21% do 2 % i moc bierna z 2616 Var do 6,3 VAR.
14
Content available remote Review of Voltage Sag Source Identification Methods for Power Quality Diagnosis
Kazemi A., Mohamed A., Shareef H., Zayandehroodi H.
Przegląd Elektrotechniczny
|
2013
|
R. 89, nr 8
143--146
EN
Voltage sag is considered as one of the most common power quality problems causing sensitive equipment to malfunction and many industrial process interruptions. Complains about the economic loss and equipment damage from industrial customers has stimulated the investigation on the voltage sag source location. As a result, many efforts have been made to know the location of voltage sags by utilizing various concepts. Generally, there are two broad categories of methods to locate voltage sags source, namely, single and multi-monitor based methods. Therefore, the purpose of this paper is to present a comprehensive review of articles that involves various methods to identify the location of voltage sag source. Accordingly, the concepts, advantages and disadvantages of these methods are discussed and tabulated for review. Although this paper does not exhibit a numerical performance comparison, most of the research publications under the subject of voltage sag source location methods have been sorted and appended for a rapid reference.
PL
Zapady napięcia są jednym z ważniejszych parametrów opisjących jakość energii. Mogą one powodować uszkodzenia urządeń i zakłócenia procesów przemysłowych. Artykuł omawia metody lokalizacji źródeł zapadów napięcia. Zaprezentowano przegląd publikacji opisujących ten problem uwypuklając zalety i wady każdej z metod.
15
Content available remote Renewable Energy Technologies and Hybrid Electric Vehicle Challenges
Azidin F. A., Hannan M. A., Mohamed A.
Przegląd Elektrotechniczny
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2013
|
R. 89, nr 8
150--156
EN
This paper introduces the utilization of selected renewable energy technologies such as solar cell, battery, proton exchange membrane (PEM) fuel cell (FC) and super-capacitors (SCs) in the electrical vehicle industry. Combination of multiple energy resources is imperative to balance the different characteristic of each resource. Concomitantly, the need of an efficient energy management system arises within the industry. Thus, existing system from past and present undergoing research papers are summarized to give a compact overview on the technology and know-how technique to readers.
PL
W artykule zaprezentowano wykorzystanie różnych źródeł energii odnawialnej – baterii słonecznych, baterii z protonową membraną i superkondensatorów w przemyśle motoryzacyjnym. Rozważano możliwość stosowania równocześnie różnych źródeł w celu zrównoważenia ich charakterystyk.
16
Content available remote Power Quality Analysis of Grid-Connected Photovoltaic Systems in Distribution Networks
Farhoodnea M., Mohamed A., Shareef H., Zayandehroodi H.
Przegląd Elektrotechniczny
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2013
|
R. 89, nr 2a
208--213
EN
This paper presents a dynamic PQ analysis on the effects of high-penetrated grid-connected photovoltaic (PV) systems in a distribution system under different weather conditions. To track practical considerations, all information on PV units and weather conditions given in this paper were collected from different solar panel producers and from the Malaysian Meteorological Department (MMD), respectively. A 1.8-MW gridconnected PV system in a radial 16-bus test system is modeled and simulated using Matlab/Simulink software to study the effects of this technology on the system under different levels of solar irradiation. The simulation results proved that the presence of high-penetrated grid-connected PV systems could cause power quality problems such as voltage raise, voltage flicker, and power factor reduction.
PL
W artykule przedstawiono analizę dynamicznych zmian mocy w dużym systemie fotowoltaicznym dołączonym do sieci, w przypadku rożnych warunków pogodowych. W badaniach wykorzystano rzeczywiste informacje pogodowe. Model sumacyjny stworzono w programie MatlabSimulink, a następnie sprawdzono jego działanie w warunkach różnego poziomu zadanego nasłonecznienia. Wyniki pokazały, że duże zespoły paneli PV, podłączone do sieci, mogą wywołać problemy z jakością energii.
17
Content available remote Optimal Sizing and Placement of Distributed Generation in Distribution System Considering Losses and THDv using Gravitational Search Algorithm
Abdul Kadir A., Mohamed A., Shareef H., Che Wanik M., Ibrahim A.A.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 4
132-136
EN
This paper presents a new method for determining optimal sizing and suitable placement for distributed generation (DG) in distribution system. A multi-objective function is created to minimise the total losses and average voltage total harmonic distortion (THDv) of the distribution system. The proposed method utilizes gravitational search algorithm (GSA )in the optimization process and its performance is compared with other optimization techniques such as particle swarm optimisation (PSO) and evolutionary programming (EP). The results show that the GSA performs better than PSO and EP by giving the best fitness value and convergence rate.
PL
W artykule opisano metodę optymalizacji rozmieszczenia i mocy generatorów energii w systemie rozproszonym. Opracowana została funkcja wielokryterialna, służąca do minimalizacji całkowitych strat i wskaźnik THD napięcia. Optymalizacja dokonywana jest z wykorzystaniem algorytmu GSA. Jego działanie zostało porównane z działaniem innych metod, jak PSO i EP. Przedstawiono wyniki porównania.
18
Content available remote Multi-Objective Optimization Based Approaches for Active Power Filter Design- A Comparison
Imani H. R., Mohamed A., Shareef H., Eslami M.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 6
98--103
EN
This paper introduces an optimal active power filter design method to compensate simultaneously current harmonics and reactive power of a nonlinear load. The power filter consists of a passive RL low-pass filter placed in series with the load and a pure active filter which has RL elements connected in series with insulated gate bipolar transistors (IGBT) based voltage source converter. The filter is supposed to inject a current into the connection node of the load and grid in order to eliminate current harmonics and its imaginary current. The voltage source converter is placed in a hysteresis feedback control loop to generate the reference current. The band width and output amplitude of the hysteresis controller are optimized with inductance of RL filters. In solving the optimization problem, three objective functions are considered which include minimizing current total harmonic distortion (THD), maximizing power factor and minimizing the IGBT bridge current. The four optimization methods applied are the goal attainment, max ordering, non-dominated sorting genetic algorithm-II and strength Pareto evolutionary algorithm 2 (SPEA2) methods. The results of the four optimization methods are compared and it is shown that the SPEA2 method gives the best performance in terms of minimizing current THD and maximizing the power factor.
PL
Przedstawiono metody optymalizacji projektowania aktywnych filtrów mocy umożliwiające kompensację prądów harmonicznych i mocy biernej przy obciążeniu nieliniowym. Analizowany filtr składa się z pasywnego filtru dolnoprzepustowego RL połączonego szeregowo z obciążeniem i filtrem aktywnym. Filtr aktywny mam elementy R:L dołączane z wykorzystaniem tranzystora IGBT.
19
Content available remote Investigation of harmonic generation from dimmable LED lamps
Uddin S., Shareef H., Hannah M.A., Mohamed A.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 4
151-155
EN
The purpose of this paper is to investigate harmonic generation from dimmable Light Emitting Diode lamps (LEDs) which are used in residential and commercial applications as an energy efficient lighting systems. It is done by conducting laboratory tests on various LED lamps and tapping the load current behavior under different conditions. Then the frequency domain analysis is performed to investigate the generated harmonics. Harmonic levels of different wattage, various branded dimmable and non dimmable LED bulbs along with dimmable compact fluorescent lamps are experimentally evaluated and compared. Experimental result shows that, all LED lamps generate very high level of harmonic during dimming operation which may affect the power quality of AC mains.
PL
W artykule opisano zagadnienie emisji harmonicznych przez ściemnianą diodę LED, wykorzystywaną do oświetlania pomieszczeń. Przeprowadzono próby laboratoryjne w różnych warunkach pracy, a na ich podstawie analizy generowanych harmonicznych. Pod tym kątem dokonano porównania działania badanych diod z innymi energooszczędnymi rozwiązaniami.
20
Content available remote Hybrid Proton Exchange Membrane Fuel Cell with Battery Energy Storage for Stand-Alone Distributed Generation Applications
Zambri N. A., Mohamed A., Shareef H., Che Wanik M.
Przegląd Elektrotechniczny
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2013
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R. 89, nr 5
161-166
EN
Hybrid power sources with energy storage elements that supply renewable energy can overcome the lack of renewable energy sources, especially with respect to load-tracking issues. Poor load-following characteristics and slow response to rapid load changes are some of the drawbacks of proton exchange membrane fuel cells (PEMFCs) because of the gas processing reaction and the fuel cell dynamics. This load tracking problem can be solved by adding an energy storage element, such as a battery or an ultra-capacitor to the system. This paper focuses on modeling of a stand-alone hybrid distributed generation (DG) system using the MATLAB/Simulink software. The model utilizes PEMFC as the main energy source, whereas the battery functions as energy storage to compensate for the limitations of PEMFC. Furthermore, the three main types of batteries are compared via simulation to identify the most suitable battery types for DG applications. The main objective of this paper is to analyze a hybrid model based on the power output across the fuel cell and in the battery terminal. Simulation results show that the delay and load-tracking problems in the PEMFC model have been resolved by the existence of the battery in the hybrid model.
PL
W artykule opisano model i badania symulacyjne hybrydowego systemu generacji energii elektrycznej. Układ złożony jest z komórek paliwowych jako głównego źródła energii oraz baterii służącej do kompensacji energii przy dynamicznej zmianie obciążenia. Dodatkowo dokonano symulacyjnego porównania zastosowania trzech typów baterii. W badaniach wykorzystano oprogramowanie Matlab-Simulink. Otrzymane wyniki potwierdziły skuteczność działania rozwiązania z dodatkową baterią.
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