Wyniki 1-10 spośród 11 dla zapytania: authorDesc:"Mahammad A. HANNAN"

D-STATCOM Pulse Selection and Transformer Configuration for Harmonic Elimination

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The sensitive industrial loads and critical commercial operations suffer from harmonics problems which can cost significant loss per incident based on process down-time, loss production, idle work forces and other factors. To overcome such problems, utility companies have made efforts to improve the quality and reliability of their electric power by introducing distribution static compensator (D-STATCOM). However, up to now, many research are going on D-STATCOM control scheme, suitable pulse and transformer design, dc capacitance effect and involvement with many power quality problems. This paper deals with the modelling and simulations of D-STATCOM model focus with the pulse selection, transformer design configuration and test distribution system. The issue of harmonics in the D-STATCOM is addressed by considering a 24-pulse so as to eliminate the generated harmonics. The harmonics eliminating performance of the D-STATCOM in 12-pulse, 24-pulse and 48-pulse are also investigated. Streszczenie. W artykule opisano budowę modelu i symulacje kompensatora statycznego D-STATCOM. Przedstawiono zagadnienie liczby pulsów, konfiguracji transformatora oraz przeprowadzono testy systemu energetycznego. Analizie poddano zagadnienie eliminacji wyższych harmonicznych w układach 12-, 24- oraz 48-pulsowym. (Dobór liczby pulsów i konfiguracji transformatora kompensatora D-STATCOM - eliminacja wyższych harmonicznych) Keywords: D-STATCOM, Pulse selection, harmonics, inverter transformer, power quality Słowa kluczowe: D-STATCOM, wybór liczby pulsów, harmoniczne, transformator falownikowy, jakość energii. Introduction D-STATCOM is a solid state, three phase inverter based power controller which is connected in shunt to a distribution feeder through a coupling transfer that matches the inverter ac output voltage to the distribution system voltage [1]. Thus, D-STATCOM is used to protect the distribution system from power quality disturbances [2]. The main comp[...]

Effect of DC Capacitor Size on D-STATCOM Voltage Regulation Performance Evaluation

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This paper describes the modelling and simulation of distribution static compensator (D-STATCOM) focused with effect of DC capacitor size and voltage regulation. Different capacitor values have been investigated to reduce the load ripple voltage during the charging and discharging of the capacitor. The optimum capacitor valuse has been determined to obtained the lowest ripple voltage within the rage of 8%. Capacitive and inductive mode of D-STATCOM operation have been also investigated and obtained results proved that the capability of the D-STATCOM in regulating the system voltage is near to the rated value of 1.0 p.u. Streszczenie. W artykule przedstawiono sposób budowy modelu i symulacje kompensatora pasywnego D-STATCOM, ze naciskiem na analizę wpływu pojemności kondensatorów oraz regulacji napięcia na jego działanie. Badania wykonano dla różnych pojemności i wyznaczono optymalną, zapewniającą najmniejsze wahania napięcia (w zakresie 8%). Analizie poddano działanie kompensatora przy charakterze pojemnościowym i indukcyjnym. (Badanie wpływu pojemności kondensatora DC na skuteczność regulacji napięcia kompensatora pasywnego D-STATCOM) Keywords: D-STATCOM, DC capacitor, power quality, voltage ripple, voltage regulation. Słowa kluczowe: D-STATCOM, kondensator DC, jakość energii, wahania napięcia, regulacji napięcia. Introduction D-STATCOM is a kind of custom power device which is used to regulate the system voltage and thereby protect the distribution system from power quality disturbances such as voltage sags, swells, voltage flicker and voltage unbalance [1, 2]. The main components of the D-STATCOM are the inverter using either GTO or IGBT, dc capacitor, coupling transformer and control system. It can be regarded as an active energy-exchanging device because it utilizes the passive energy storage component to realize the energy storing and exchanging and the switches to control the reactive power flow between different phases of a d[...]

Efficient Low-Power Recovery Circuits for Bio-implanted Micro- Sensors

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This paper presents a modified sub-electronic circuit with low-power recovery circuits to be implemented in implanted micro-sensor used to stimulate the human and animals’ nerves and muscles. The system based on ASK modulation techniques operated with 13.56 MHz according to industrial, scientific, medical (ISM). The modulation index is 12.6% to achieve minimum power consumption to avoid the tissue heating. The system consists of external part with modified class-E power amplifier efficiency 87.2%, and internal part consists of a voltage doubling rectifier with selfthreshold cancellation and efficient low-dropout voltage regulator based on series NMOST transistor using 0.35 μm technology to offer very stable 1.8 DC V. The produced voltage used to power the sub-electronic implanted device with steady voltage even in any changing with the implanted load resistance. The mathematical model is given. The design is simulated using OrCAD PSpice 16.2 software tools and for real-time simulation, the electronic workbench MULISIM 11 has been used to simulate the class-E power amplifier. Streszczenie. W artykule przedstawiono zmodyfikowany układ pół-elektroniczny do zastosowania w implantowych mikro-czujnikach stymulujących pracę ludzkich i zwierzęcych nerwów i mięśni. Urządzenie posiada obwód odzyskiwania mocy w przypadku obniżonego zasilania w układzie. W proponowanym rozwiązaniu zastosowano modulację ASK o częstotliwości 13.56MHz i indeksie 12.6% w celu minimalizacji zużycia energii. Przedstawiono także model matematyczny urządzenia. Badania symulacyjne przeprowadzono w środowisku OrCAD PSpice 16.2 oraz MULISIM 11 do symulacji w czasie rzeczywistym wzmacniacza mocy klasy E. (Sprawny układ odzyskiwania mocy w implantowych mikro-czujnikach). Keywords: ASK modulation; Class-E power amplifier; Rectifiers; Bio-implanted devices; Voltage regulators. Słowa kluczowe: modulacja ASK, wzmacniacz klasy E, prostownik, urządzenia implantowane, regulator n[...]

Lane Departure Detection and Transmisson using Hough Transform Method

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Vehicles need to be re-advancing by video transmission among vehicles for safety and cooperative deriving. The video images captured from camera could help the driver to monitor the surroundings as well as transmit the compressed images over vehicular communication network. Video over wireless communication has a lot of potential applications in intelligent transportation systems (ITS).Video streaming utilizes high bandwidth data links to transmit information. The high-bandwidth systems required larger equipment, better line-of-sight, and more complex mechanism for reliable transmit ion over the network. The intended platform for the system described in this study, is to develop a software defined algorithm for automatic video compression and transmission. The proposed algorithm is able to robustly find the left and right boundary of the lane using Hough Transform method and transmit over the network. Therefore the limitations of high-bandwidth equipment become more significant in a tactical scenario. The results show that the proposed method works well on marked roads and transmission in various lighting conditions. Streszczenie. W artykule przedstawiono algorytm kompresji i transmisji obrazów do zastosowania w komunikacji bezprzewodowej w sieci samochodowej. Przy pomocy transformacji Hough algorytm określa lewą i prawą granicę pasa i przesyła dane do sieci. Przeprowadzono badania weryfikujące działanie algorytmu, które wykazały jego skuteczność na oznaczonych drogach przy różnych warunkach oświetlenia. (Zastosowanie transformacji Hough w detekcji wyjazdu z pasa i transmisji danych). Keywords: Video Transmission, Wireless Communications, Lane departure, Segmentation, Filter and Thresholding. Słowakluczowe: transmisja wideo, komunikacja bezprzewodowa, wyjazd z pasa, segmentacja, filtracja, progowanie. Introduction Now a day’s we observe that most researchers focused on increasing need for traffic safety systems to reduce the risk of [...]

Rule-based Fuzzy and V/f Control for Induction Motor Speed Responses Using SVPWM Switching Technique DOI:10.15199/48.2015.03.32

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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. Streszczenie. 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. Fuzzy logic sterownik wykorzystujący modulację SVPWM do kontroli szybkości silnika indukcyjnego Keywords: Fuzzy logic control, Induction motor, V/f controller, SVPWM, Inverter. Słowa kluczowe: Logika rozmyta,. Silnik indukcyjny, sterowanie prędkością Introduction Three-phase induction motor (TIM) drives are widely used in many applications, such as in utility companies, industrial plants, machine tools, and robotics. For TIM drive applications, the motor drive speed controller should be both efficient and robust [1]. Many types of TIM speed controllers have been utilized in previous works. For example, the proportional-integral-derivative (PID) controller[...]

Gravitational search optimization approach to improve fuzzy logic speed controller for induction motor drive DOI:10.15199/48.2016.08.54

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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. Streszczenie. 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. Optymalizacja typu grawitacyjne badanie jako metoda poprawy jakości sterownika fuzzy logic zastosowanego do silnika indukcyjnego Keywords: Fuzzy logic control, gravitational search algorithm, particle swarm optimization, induction motor, inverter. Słowa kluczowe: sterowanie fuzzy logic, algorytm grawitacyjnego badania, silnik indukcyjny [...]

Light Vehicle Energy Management System using Multi-Power Sources

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This paper describes the modelling of the energy management system (EMS) of light vehicles using hybrid multi-power source systems. The hybrid system included a fuel cell (FC), a battery, supercapacitors (SC) and a photovoltaic cell. The battery was used as the primary power source for driving the vehicle. Other sources were used as supplemental power sources for medium range vehicle usage. The control algorithm was developed as a switching mechanism used to trigger between the energy sources based on the drive of the vehicle power system as a means of examining the electrical power flow. The control algorithm was used to manage the switching operation of power supplies for the EMS during light vehicle operation. The results showed that the models were operating efficiently based on the switching control algorithm and management of the energies from various sources. Streszczenie. Opisano modelowaniem system zarządzania energią lekkich pojazdów. W skład systemu wchodzą: bateria, superkondensator i bateria fotowoltaiczna. Szczególną uwagę zwrócono na mechanizm przełączania między źródłami energii. (System zarządzania energią w lekkich pojazdach mechanicznych) Keywords: Fuel cell, PV, supercapacitors, energy management system. Słowa kluczowe: lekkie pojazdy mechaniczne, bateria, zarządzanie energią. Introduction Light vehicles, such scooters or auto rickshaws, are important modes of transportation in many Asian countries, including Malaysia and Indonesia [1, 2]. The energy source of these vehicles comes from fossil fuels that have a negative impact on the cities through pollution and noise. Multi-power sources from renewable energies can be implemented as an alternative fuel source in electric light vehicles. The renewable energies that can be used practically in vehicles include FC, solar, battery and SC. These four energy sources may be used in concert so that vehicles may have sufficient power and energy capacity in the future. Thi[...]

Harmonics and thermal characteristics of low wattage LED lamps

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This paper presents harmonics and thermal characteristic of Light Emitting Diode (LEDs) Lamps which are used in residential and commercial applications as energy efficient lighting bulbs. It is done by performing experimental tests on various LED lamps available in the market. The current drawn by several LED lamps are first measured to investigate the electrical characteristics. These measurements provide current harmonic characteristic of individual lamps. Then various configurations of LEDs were connected to a laboratory scale feeder to analyze the diversity factors. Furthermore, heat generation levels of the tested LED lamps are investigated to measure the thermal characteristics of LED lamps. The results show that individual LED bulbs produce considerable amount of harmonics but it could be reduced by combining various types of LED bulbs. Furthermore, the diversity factor could be improved if LED lamps are mixture with Compact Fluorescent Lamps (CFLs). Results also shows that the thermal characteristic of LED lamps is much better compare to the performance of CFLs. Streszczenie. W artykule przedstawiono analizę harmonicznych oraz charakterystyki termiczne żarówek z diodami LED, stosowanymi komercyjnie w lampach. Badania przeprowadzono na losowo wybranych lampach dostępnych na rynku. Wskazano rozwiązania mogące zredukować ilość generowanych harmonicznych. (Charakterystyka harmonicznych i termiczna żarówek małej mocy z diodami LED) Keywords: LEDs, CFLs, Harmonic Distortion, Diversity factors, Power quality. Słowa kluczowe: LED, CFL, zakłócenia harmonicznymi, jakość energii, współczynnik niejednoczesności. Introduction Recent research reports highlight that, Light Emitting Diode Lamps (LEDs) has almost 2 times better efficiency compared to Compact Fluorescent Lamps (CFLs) and 8 to10 times more efficient then incandescent lamps. Also the life time of LED is much longer than other types of lamp and they are environmentally friendly due t[...]

Power Amplifier Frequency Controller Using feedback control techniques for Bio-implanted Devices DOI:10.15199/48.2015.12.07

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Switch mode power amplifier is used in biomedical devices widely. The power amplifier supplies the required operating power to the implanted devices. Zero voltage switching (ZVS) operation of class-E power amplifier leads to convert DC voltage to AC with high efficiency and workings frequency. Frequency has a great function in powering most of the biomedical implanted devices. Frequency shift caused by inductors and capacitors used in the circuit can cause load variation or changing in mutual displacement or they may lead to instability and data loss of the implanted devices. So switching-mode frequency control is the key problem in the biomedical device powering system. This paper focused on the design of a frequency controlled power amplifier to improve the controller's efficiency in terms of speed and better results. The objective of this work is to control the operating frequency. Feedback control method is used by using proportional integral derivative controller (PID), proportional integral (PI) and voltage controlled oscillator (VCO) to reduce the phase shift and settling time. The Bode plot and Nyquist stability criterion analyses show that the developed power amplifier frequency controller is stable and perform well to improve the controller efficiency. Streszczenie. W artykule opisano wzmacniacz mocy używany w technice bio-implantów. Wzmacniacz klasy E z operacją ZVS przekształca stałe napięcie na napięcia AC. Kontrola częstotliwości tego napięcia ma ważne znaczenie ponieważ częstotliwość może się zmieniać przy obecności elementów L, C w układzie. W pracy opisano metode kontroli częstotliwości tego napięcia. Kontrola częstotliwości wzmacniacza mocy wykorzystywanego do zasilania bio-implantów Keywords: Biomedical implanted devices, Frequency control, PID controller, class-E power amplifier, voltage controlled oscillator (VCO) Słowa kluczowe: wzmacniacz mocy klsy E, bio-implanty, kontrola częstotliwości Introduction Recently, [...]

Traffic Sign Classification based on Neural Network for Advance Driver Assistance System DOI:10.12915/pe.2014.11.44

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Traffic sign is utmost important information or rule in transportation. In order to ensure the transportation safety the automotive industry has developed Advance Driver Assistance System (ADAS). Among the ADAS system, development of TSDR is the most challenging to the researchers and developers due to unsatisfying performance. This paper deals with, automatic traffic sign classification and reduces the effect of illumination and variable lighting over the classification scheme by using neural network according to the traffic sign shape. There are three main phase of the classification scheme such as; pre-processing using image normalization, feature extraction using color information of 16-point pixel values and multilayer feed forward neural network for classification. An accuracy rate of 84.4% has been achieved by the proposed system. Overall processing time of 0.134s shows the system is a fast system and real-time application. Streszczenie. W artykule opisano metodę automatycznego rozpoznawania I klasyfikacji znaków drogowych z przenaczeniem do inteligentnych systemów wspomagania kierowcy ADAS. Do tego celu wykorzystano sieci neuronowe przeprowadzając normalizację obrazu, ekstrakcję cech i klasyfikację. Osiągnie™o dokładność rozpoznawania rzędu 84% przy przeciętnym czasie rozpoznawania około 0.13 s. Rozpoznawanie i klasyfikacja znaków drogowych z wykorzystaniem sieci neuronowych Keyword: Traffic sign classification; advance driver assistance system; image normalization; neural network. Słowa kluczowe: rozpoznmawanie znaków drogowych, sieci neuronowe, system ADAS doi:10.12915/pe.2014.11.44 Introduction Traffic sign and classification is part of the Traffic Sign Recognition (TSR) system and it is one of the developed systems under Advance Driver Assistance (ADAS) which help to improve the safety issue on the road. In this era of industrialization, the gradual increase of roads and traffic occurs and thus the number of traffic ac[...]

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