Rectifier

This paper represents the modeling and simulation of 2 MW Direct Drive permanent magnet synchronous generator (PMSG) Wind energy conversion system (WECS). The modeling of wind turbine and PMSG is carried out in simulink to determine its parameter. WECS consists different components namely Wind turbine, Generator, rectifier-inverter, controller system including transformer, grid etc. The PMSG and converter model are established in the d-q model. Renewable energy technologies offers clean, abundant energy gathered from self-renewing resources such as the sun, wind etc. As the power demand increases, power failure also increases. So, renewable energy sources can be used to provide constant loads. A new converter topology for hybrid wind/photovoltaic energy system is proposed. Hybridizing solar and wind power sources provide a realistic form of power generation. Simulation is carried out in MATLAB/ SIMULINK software and the results of the Cuk converter, SEPIC converter and the hybridize...

The reliability of a motor control based on a variable speed drive is an important issue for industrial applications. Most of these machines are inverter based induction motors and are used in specific and complex industrial installations. Unlike the induction motor, the feeding part is very delicate and sensitive to faults. In order to improve system performance, it is therefore very important for a researcher to know the impact of a fault on the whole of his drive system. This paper discusses the short-circuit fault of the DC-link capacitor of an inverter fed induction motor. The simulation results of this type of faults are presented and its impact on the behavior of the rectifier, the inverter as well as the induction motor analyzed and interpreted.

For the improvement of efficiency and power factor, a bridgeless single-phase ac-dc soft switched PWM cuk converter with multiplier control technique is proposed. This paper emphasizes more on the converter efficiency and power factor. The conduction losses and input current harmonics of the proposed converter is very less due to the absence of the input diode bridge and also during each switching cycle, only two semiconductor switches are present in the current path unlike other conventional Cuk converters. Soft switching (ZVS) technique is applied by using an auxiliary circuit to improve the efficiency of the proposed converter. Multiplier control technique is provided to regulate the output which also ultimately improves the efficiency. Power factor is almost unity due to less input current harmonics. The circuit configuration, principle of operation, design procedure and simulation results are presented.

In this study, 2.5 kW single-phase pulse-width modulated rectifier is simulated with three different control techniques to investigate the performance of controllers. Rectifier simulation is performed in Matlab / Simulink environment by using hysteresis current control, sinusoidal pulse width modulation and voltage oriented control techniques. In the performance comparison of the control techniques, considering the switching frequencies, the total harmonic content of the current drawn from the grid, the phase difference between the grid voltage and the grid current, and the DC bus voltage regulation at the output are considered as comparison criteria. The switching frequency is set to 35 kHz in sinusoidal pulse width modulation and voltage oriented control techniques. Since the switching frequency is variable in the hysteresis current control technique, the average and instantaneous switching frequency are calculated for different hysteresis band values. In the results with the technique, the switching frequency varies between 18.52 kHz and 47.6 kHz, while the average switching frequency is 34.6 kHz. As a result, the total harmonic distortion of the grid current with hysteresis current control, sinusoidal pulse width modulation and voltage oriented control techniques is 3.69%, 1.12% and 1.82%, respectively. The synchronization with the grid voltage is achieved with all techniques, and the DC voltage is regulated with active power. TEK FAZLI PWM DOĞRULTUCU KONTROL TEKNİKLERİNİN KARŞILAŞTIRILMASI Özet Bu çalışmada, 2.5kW gücünde tek fazlı darbe genişlik modülasyonlu doğrultucunun üç farklı kontrol yönteminde simülasyonu yapılarak bu yöntemlerin performansı incelenmiştir. Histerezis akım kontrolü, sinüzoidal darbe genişlik modülasyonu ve gerilim odaklı kontrol yöntemleri kullanılarak Matlab/Simulink ortamında doğrultucu simülasyonu gerçekleştirilmiştir. Kontrol yöntemlerinin performans karşılaştırmalarında anahtarlama frekansları dikkate alınarak şebekeden çekilen akımın toplam harmonik içeriği, şebeke gerilimi ile arasındaki faz farkı ve çıkıştaki DC bara gerilimi regülasyonu karşılaştırma kriterleri olarak ele alınmıştır. Sinüzoidal darbe genişlik modülasyonu ve gerilim odaklı kontrol yöntemlerinde anahtarlama frekansı 35 kHz seçilmiştir. Histerezis kontrol yönteminde anahtarlama frekansı değişken olduğundan dolayı farklı hata bandı değerleri için anahtarlama frekans değişimi hesaplanarak ortalama ve anlık anahtarlama frekansı tespit edilmiştir. Histerezis akım kontrol yönteminde anahtarlama frekansı 18,52 kHz ile 47,6 kHz aralığında değişirken ortalama anahtarlama frekansı 34,6 kHz olmuştur. Yapılan çalışma sonucunda histerezis akım kontrolü, sinüzoidal darbe genişlik modülasyonu ve gerilim odaklı kontrol yöntemlerinde şebeke akımı toplam harmonik bozulumu sırasıyla %3,69, %1,12 ve %1,82 olmuştur. Tüm yöntemlerde şebeke ile senkronizasyon sağlanmış ve DC bara gerilimi regülasyonu şebekeden aktif güç çekerek gerçekleştirilmiştir. Anahtar Kelimeler: Histerezis akım control, Sinüzoidal PWM, Doğrultucu Cite ISEN, E., (2021). "Comparative Study Of Single-Phase Pwm Rectifier Control Techniques", Mugla Journal of Science and Technology, 7(1), 44-52.

The purpose of this assignment was to investigate, analyse and explain the operation of half wave and full wave, non-controlled, bridge rectifier circuits under a number of differing load conditions. A series of current, voltage and waveform measurements were then carried out in order to calculate power into the load, ripple factor, transformer utilisation factor and rectifier efficiency for each type of circuit. From the results obtained, it will be seen that the full wave rectifier circuit is a more efficient way to convert an ac supply to dc.

The original contribution of this work is contained in the following statements. A general mathematical model of auxiliary DC installations in power plants was developed in order to he used for analyzing short circuit conditions according to the references [I] and 121. It was concluded that the transient state during short circuit has to be taken into account. The essence of this new approach is the new mathematical model which takes into consideration not only resistances, but inductances and capacities of auxiliary DC elements as well as the active network in front of the rectifier. Based on this mathematical model, an original program package was developed and used for analyzing and dimensioning auxiliary DC installations in power plants according to 1101. The results obtained by means of the program package are relevant for dimensioning all elements of auxiliary DC installations, particularly when protection devices are considered Kqwora3: DC auxiliary installations, short-circuit, transient behavior, protection, selectivity

An ac-to-dc converter which draws sinusoidal and inphase current waveforms from the ac power source is described. Harmonic and power factor measurements obtained from a fieldeffect transistor (FET) converter operating at 45 kHz for a singlephase and a three-phase connection are presented. A stability analysis and design methodology are given.

Το βιβλίο αυτό απευθύνεται σε προπτυχιακούς φοιτητές ανώτατης εκπαίδευσης και ειδικά φοιτητές των Τεχνολογικών Εκπαιδευτικών Ιδρυμάτων. Εφαρμόζει μια δομημένη προσέγγιση κατά την οποία ο φοιτητής καλείται να εκτελέσει 10 διαφορετικές εργαστηριακές ασκήσεις, διάρκειας δύο διδακτικών ωρών, σε περιβάλλον MATLAB και SIMULINK. Η εκπαιδευτική προσέγγιση έχει ως κύριο στόχο να ωθήσει τον φοιτητή να εργαστεί χρησιμοποιώντας το λογισμικό από την πρώτη στιγμή για να εξοικειωθεί με βασικές αρχές, έννοιες και κυκλώματα των ηλεκτρονικών ισχύος. Γίνεται συνειδητή προσπάθεια αποφυγής εκτενής παρουσίασης του λογισμικού αλλά και του γενικότερου θεωρητικού υποβάθρου. Νέες έννοιες αλλά και λειτουργίες του λογισμικού εισάγονται σταδιακά, ώστε να διατηρηθεί το ενδιαφέρον, να αποφευχθεί η επανάληψη παρόμοιων βημάτων σε κάθε άσκηση και να μετριασθεί η ροή της πληροφορίας. Κάθε άσκηση ολοκληρώνεται με παράθεση των βασικών σημείων και των εκπαιδευτικών στόχων. Η προσέγγιση που περιγράφεται σε αυτό το βιβλίο ακολουθήθηκε κατά το χειμερινό εξάμηνο του 2014-2015 στο Τμήμα Ηλεκτρολόγων Μηχανικών Τ.Ε. του ΤΕΙ Κρήτης. Στο τέλος του κύκλου των ασκήσεων, οι φοιτητές κλήθηκαν να απαντήσουν σε σχετικό ερωτηματολόγιο. Το διδακτικό πλάνο καθώς και μια πρώτη ανάλυση των απαντήσεων των φοιτητών στο ερωτηματολόγιο παρουσιάστηκαν στο Πανελλήνιο Συνέδριο Ηλεκτρονικής και Τηλεπικοινωνιών (Pan-Hellenic Conference on Electronics and Telecommunications - PACET) του 2015. Η ανάλυση των απαντήσεων έδειξε ότι, σύμφωνα με την κρίση των φοιτητών, η συγκεκριμένη προσέγγιση βελτίωσε σημαντικά τις γνώσεις και την ευχέρεια χρήσης του συγκεκριμένου λογισμικού αλλά και τις βασικές γνώσεις τους για θεμελιώδεις έννοιες και ζητήματα της ευρύτερης επιστήμης του ηλεκτρολόγου μηχανικού. Παράλληλα πέτυχε να αυξήσει σημαντικά το ενδιαφέρον τους για τον τομέα των ηλεκτρονικών ισχύος αλλά και για το χρησιμοποιούμενο λογισμικό. Σημαντικό ποσοστό των φοιτητών θεώρησε τις γνώσεις που αποκτήθηκαν χρήσιμες για άλλα μαθήματα, για την εξομοίωση άλλων κυκλωμάτων στο μέλλον και για την πτυχιακή τους εργασία. Το γενικότερο ποσοστό ικανοποίησης έφτασε το 90%.

ABSTRACT The Full Bridge converter topology modulated in phase shift is one of the most popular converters used to obtain high efficiency conversion, especially in high power and high voltage applications. This converter topology combines the simplicity of fixed frequency modulations with the soft switching characteristic of resonant converters but, if a diode rectifier is used as output stage, it suffers of severe overshoot voltage spikes and ringing across the rectifier. In this paper, a new regenerative active snubber is widely studied and developed to reduce this drawback. The proposed snubber is based on a combination of an active clamp with a buck converter used to discharge the snubber capacitor. The snubber gate signal is obtained by using those of the phase shift modulation.

Control techniques for PWM rectifiers in ac adjustable speed drives are presented. In particular, the so-called virtual flux-oriented control (VFOC) and virtual flux-based direct power control (VF-DPC) schemes are described and compared with their voltage-based counterparts, that is, the voltage-oriented control (VOC) and voltage-based direct power control (V-DPC) techniques. Theoretical background is provided, and results of computer simulations and laboratory experiments are given, documenting advantages and disadvantages of the individual control strategies.

The design of an input filter for the six-pulse bridge rectifier is discussed. For industrial applications of mid-range power, two types of input filter are examined. It is shown that these filters with minimum number of components can meet most operational requirements if designed properly. The variation of performance factors with filter type and parameters are discussed. As the ultimate decision in selecting the filter components depends on the type of application, the design guidelines are deseribed. The materials for custom designing of the filter arl included. The features and advantages of each type of filter are outlined. For comparison purposes, several design examples are also included.

The present paper is an experimental study of the harmonic absorbed currents by three-phase rectifiers. Laboratory tests have been performed with a rectifier to characterize its absorbed harmonic currents (magnitude and phase angle). From these results, a database that characterizes rectifier harmonic behavior experimentally and allows the rectifier currents to be easily calculated is proposed. The database applicability is experimentally studied in two laboratory tests. The results are validated with PSpice simulations.

This paper represents the modelling and simulation of 2 MW Direct Drive PMSG Wind energy conversion system (WECS). The modelling of wind turbine and PMSG is carried out in simulink to determine its parameter. WECS consists different components namely Wind turbine, Generator, rectifier-inverter, controller system including transformer, grid etc. The PMSG and converter model are established in the d-q model.

This paper represents the modeling and simulation of 2 MW Direct Drive permanent magnet synchronous generator (PMSG) Wind energy conversion system (WECS). The modeling of wind turbine and PMSG is carried out in simulink to determine its parameter. WECS consists different components namely Wind turbine, Generator, rectifier-inverter, controller system including transformer, grid etc. The PMSG and converter model are established in the d-q model. Renewable energy technologies offers clean, abundant energy gathered from self-renewing resources such as the sun, wind etc. As the power demand increases, power failure also increases. So, renewable energy sources can be used to provide constant loads. A new converter topology for hybrid wind/photovoltaic energy system is proposed. Hybridizing solar and wind power sources provide a realistic form of power generation. Simulation is carried out in MATLAB/ SIMULINK software and the results of the Cuk converter, SEPIC converter and the hybridized converter are presented.

This paper proposes two methods of speed controlling for separately excited dc motor. The methods are
provided with their schematics and block diagram, the construction of each scheme was made in breadboard
at the first. This eases the testing and troubleshooting of the circuit, and each scheme was constructed in
separate breadboard. The results was obtained by using the oscilloscope and the digital multimeter, after
assuring of the results obtained, the next step was to fabricate the PCB and demonstrate it in separate boards
and jumper wires were used to route the connectors. It was found that the results obtained after fabricating the
PCB is similar to that while testing on the breadboard. Afterwards testing the motor was done for the both
schemes. The two methods are contributed to the same major factor on controlling the speed of the dc motor,
and it was achieved by varying the firing angle, and hence triggers the SCR. Regardless the construction of
each scheme, the results obtained proves the theoretical part, and scheme 2 is considered cost effective than
scheme 1 and on the other hand it is more reliable in term of size, construction and components availability
and accessibility.
Keywords: Thyristor, Firing angle, Half wave controlled rectifier.

Lab : Elda & kontrol PENGUKURAN PARAMETER PENYEARAH SATU FASA Nomor: Prodi : Teknik Otomasi Indrustri Semester: III I. Tujuan Percobaan : setelah praktikum diharapkan dapat mempraktikan :  Membangun rangkaian penyearah satu phasa setengah gelombang.  Melakukan pengukuran bentuk gelombang penyearah satu phasa setengah gelombang.  Mengetahui besarnya parameter penyearah satu phasa. II. Teori pengantar : Sumber tegangan arus searah (DC),selain dapat dihasilkan oleh sumbersumber tegangan seperti battery, juga dapat dihasilkan dari sumber tegangan arus bolak-balik dengan menggunakan rangkaian penyearah. Ditinjau dari sumbernya, rangkaian penyearah dapat diklasifikasikan sebagai penyearah 1 phasa. Sedangkan dari bentuk gelombangnya tegangan keluaranya dapat di klasifikasikan sebagai penyaearah setengah gelombangdan penyearah gelombang penuh. Rangkaian penyearah setengah gelombang, seperti ditunjukan pada gambar 1.1 dapat dikonstruksi dengan menggunakan sebuah dioda dan sebuah tranformator. Trasformator digunakan untuk mendapatkan nilai tegangan keluaran DC yang dikehendaki, sedang dioda menghasilkan tegangan keluaran satu arah pada setiap setengah siklus tegangan sumber. Gambar 1.1 penyearah satu phasa setengah gelombang

The aim of this paper is to present a review of recently used current control techniques for three-phase voltagesource pulsewidth modulated converters. Various techniques, different in concept, have been described in two main groups: linear and nonlinear. The first includes proportional integral stationary and synchronous) and state feedback controllers, and predictive techniques with constant switching frequency. The second comprises bang-bang (hysteresis, delta modulation) controllers and predictive controllers with on-line optimization. New trends in the current control-neural networks and fuzzy-logicbased controllers-are discussed, as well. Selected oscillograms accompany the presentation in order to illustrate properties of the described controller groups.

Induction motors are widely used AC motors in industrial area. Advanced semiconductor technology & use of microcontroller have made the speed control of induction motor easier. The proposed paper represents variable speed control application of induction motor using v/f method. In this system, the speed of the induction motor can be adjusted to user defined speed. The actual speed & reference speed is compared & the difference is adjusted by changing the firing angles of IGBTs. The system is tested & experimental results are recorded for variable speed under various load conditions.

1. Praktikum dapat memahami prinsip dasar penyearah tak terkontrol full – wave tiga phasa 2. Praktikum dapat menganalisa dan menyimpulkan hasil praktikum II. DASAR TEORI Penyearah diode gelombang penuh tiga phasa menggunakan sistem jembatan dengan enam buah diode R1, R3, dan R5 katodanya disatukan sebagai terminal positif. diode R4, R6, dan R2 anodanya yang disatukan sebagai terminal negative. Tegangan DC yang dihasilkan memiliki enam pulsa yang dihasilkan oleh masing-masing diode tersebut. Tegangan DC yang dihasilkan halus karena tegangan riak (ripple) kecil dan lebih rata. Urutan konduksi dari keenam diode dapat dilihat dari siklus gelombang sinusoida yang konduksi secara bergantian. Konduksi dimulai dari diode R1 + R6 sepanjang sudut komutasi 60°. Berturut-turut disusul diode R1 + R2, lanjutnya diode R3 + R2, urutan keempat R3 + R4, kelima R5 + R4 dan terakhir R5 + R6 Jelas dalam satu siklus gelombang tiga phasa terjadi enam kali komutasi dari keenam diode secara bergantian dan bersama-sama. Rangkaian penyearah 3 fasa seperti pada Gambar 2.3 Gambar rangkaian dan gelombang Full Wave Rectifier [1] [1] https://accurations.wordpress.com/2012/08/21/penyearah-diode-gelombang-penuh-tiga-phasa/

A circuit technique that reduces the boost-converter losses caused by the reverse-recovery current of the rectifier is described. The losses are reduced by inserting an inductor in the series path of the boost switch and rectifier to control the di=dt di=dt di=dt rate of the rectifier during its turn off. The energy from the inductor after the boost switch turn off is returned to the input or delivered to the output via an active snubber.

A systematic and accurate method is described for the calculation of the harmonic content of the six-pulse bridge rectifier with input filter. Both the converter output ripple and input distortion are included in the calculations. The accuracy of the results is verified by experiment. It is shown that, under certain conditions, the output ripple can be neglected, leading to derivation of simple and explicit formulas for the converter harmonics. Based on the approximate formulas thus developed, major effects of the input filter on the converter characteristics are discussed and graphically shown. It is found that the control range and the firing angle need to be redefined compatible with the characteristics of the rectifier in the presence of the input filter. In addition, the maximum active power delivered to the load is determined by the filter rather than the load.

High Voltage solid state Digital Capacitor IC
Reliability, availability, maintain free, and durability TECHNOLOGY PROVIDES TANGIBLE BENEFITS FOR over 100,000h life cycles. Now a day, AC to DC power converter such likes conventional fly-back technology SMPS are Power Factor (PFC) controllers and PFC/PWM combo controllers offer cost and energy saving solutions that address the demanding requirements of a diverse range of medium and high power Switch Mode Power Supply (SMPS) designs. But aluminum electrolytic capacitor makes decrease efficiency and life time failure.

In this article, a modern precise full-wave Rectifier by using non-linear applications of op-amp circuit is presented. By using an appropriate design for proposed op-amp circuit, this circuit is designed as the output is not saturated. A precise full-wave rectifier can be designed for high frequencies. The objective of the proposed circuit is more focused on minimum and maximum input voltage. In the structure of this rectifier Fully-Differential circuit for op-amp circuit is used, and for ideal diode, contact diode is used. Output voltage simulation has been done by using Hspice software in 0.18 um technology.

The trend toward deploying inverters in interfacing distributed generation (DG) systems to the grid has raised the importance of control and power quality aspects of inverters. Using multilevel inverters in DG systems, one can achieve high power quality outputs with realistic switching frequency. The four-leg three-level inverter topology is proposed for DG applications in three-phase four-wire systems, for its full dc link utilization and low voltage ripple on the dc link capacitors. A novel algorithm of three-dimensional space vector modulation (3D-SVM) is proposed for controlling a four-leg threelevel inverter. The issues of vector selection and switching sequence determination are described. Simulation results are compared with those of a three-leg three-level inverter to assess the effectiveness of the proposed 3D-SVM and to establish the advantages of the four-leg three-level topology over conventional three-leg three-level one.

RF harvesting circuits have been demonstrated for more than 50 years, but only a few have been able to harvest energy from freely available ambient (i.e., non-dedicated) RF sources. In this paper, our objectives were to realize harvester operation at typical ambient RF power levels found within urban and semi-urban environments. To explore the potential for ambient RF energy harvesting, a city-wide RF spectral survey was undertaken from outside all of the 270 London Underground stations at street level. Using the results from this survey, four harvesters (comprising antenna, impedance-matching network, rectifier, maximum power point tracking interface, and storage element) were designed to cover four frequency bands from the largest RF contributors (DTV, GSM900, GSM1800, and 3G) within the ultrahigh frequency (0.3-3 GHz) part of the frequency spectrum. Prototypes were designed and fabricated for each band. The overall end-to-end efficiency of the prototypes using realistic input RF power sources is measured; with our first GSM900 prototype giving an efficiency of 40%. Approximately half of the London Underground stations were found to be suitable locations for harvesting ambient RF energy using our four prototypes. Furthermore, multiband array architectures were designed and fabricated to provide a broader freedom of operation. Finally, an output dc power density comparison was made between all the ambient RF energy harvesters, as well as alternative energy harvesting technologies, and for the first time, it is shown that ambient RF harvesting can be competitive with the other technologies.

This work presents a dual converter employed as a rectifier with power factor regulation and bidirectional power flow. The active and reactive power flowing into the converter is controlled using an optimized direct power control algorithm. The multilevel structure of the converter is exploited to control the voltage level in each sub converter by selecting the modulation method from one commonly found in the literature, with the option of clamping one of the sub converters. These modulation methods are used to control the power taken by each sub converter, providing limited DC link voltage regulation. The system is first simulated in SIMULINK and the results were experimentally validated using a digital signal processor (DSP) based test rig.

The diversified nature of power generation and load requirement make the power conversion as mandatory. The power conversion system involves a converter topology and switching strategy. The power converter becomes helpless if the nature of input changes. For example, for ac loads with dc inputs, an inverter module is preferred and it becomes useless if the input becomes ac. Hence a unique topological structure which can make any type of output from the input given is more appreciable. That is a single topology which can perform all types of power conversions, namely rectification, inversion, dc chopping and cyclo-conversion, is today's need. This paper proposes an unique power converter topology which can perform all above mentioned power conversions. The proficiency of the power converters is more depends on the switching strategy, that is the how the pulse patterns are generated. This paper also proposes two switching strategies for cyclo-conversion. The proposed half wave symmetry variable firing angle method (HWSVFAM) and quarter wave symmetry variable firing angle method (QWSVFAM) offer enhanced fundamental component at low total harmonic distortion (THD). Complete analysis of the proposed topology and the control strategies are done in MATLAB-Simulink tool.

In this paper, design procedure and characteristics of an RF energy harvesting circuit based on single-stage voltage multiplier rectifier have been discussed and analyzed. This circuit is capable to recycle RF energy at 2.45 GHz, and by connecting to a 2.45 GHz antenna, it is possible to form a complete rectenna device. The values of output dc voltage and power according to the received RF power have been measured and the best value of load resistance to harvest maximum output dc power has been selected by simulation.

For the improvement of efficiency and power factor, a bridgeless single-phase ac-dc soft switched PWM cuk converter with multiplier control technique is proposed. This paper emphasizes more on the converter efficiency and power factor. The conduction losses and input current harmonics of the proposed converter is very less due to the absence of the input diode bridge and also during each switching cycle, only two semiconductor switches are present in the current path unlike other conventional Cuk converters. Soft switching (ZVS) technique is applied by using an auxiliary circuit to improve the efficiency of the proposed converter. Multiplier control technique is provided to regulate the output which also ultimately improves the efficiency. Power factor is almost unity due to less input current harmonics. The circuit configuration, principle of operation, design procedure and simulation results are presented.

This work presents harmonic harvester Rectenna integrated power management circuitry for improving RF-DC power conversion efficiency. The circuitry is developed for battery charging or energy storage application; resistance emulation method is used to realize a matching load resistance at output terminals. The proposed technique is useful for harvesting near maximum output power from the dual rectifiers (fundamental and harmonics) independently. Also, it delivers the combined maximal power to the energy storage cell. The power management module based on dual input buck-boost converter with simple open loop control is utilized.

Induction motors are widely used AC motors in industrial area. Advanced semiconductor technology & use of microcontroller have made the speed control of induction motor easier. The proposed paper represents variable speed control application of induction motor using v/f method. In this system, the speed of the induction motor can be adjusted to user defined speed. The actual speed & reference speed is compared & the difference is adjusted by changing the firing angles of IGBTs. The system is tested & experimental results are recorded for variable speed under various load conditions.

The method of using Boost type of converter was proposed for a 300W single-phase rectifier in this paper. By designing the necessary techniques and methodology, the overall Power Factor (PF) and Total Harmonic Distortion would be improved to the expectation. The cause of having low PF and high THD for a diode-capacitor type of rectifiers is related to non-linearity of the input current. Method of re-shaping the input current waveform to be similar pattern as the sinusoidal input voltage is done by the Boost converter and the related controls that act as a Power Factor Correction (PFC) circuit. The results of the designed system were compared against with and without PFC control. The international standard IEC 61000-3-2 on harmonics was used as the reference to determine the performance of the project.

In this paper, the design and implementation of a model reference adaptive control (MRAC) applied to a three-phase three-level boost-type Vienna rectifier are presented. The proposed adaptive controllers are designed for inner loops, targeting to balance partial output DC bus voltages, while maintaining unity power factor and minimum AC line currents harmonics. The dqo nonlinear multiple-input multiple-output (MIMO) state space model of the rectifier is first overparameterized. Then, the controllers are designed based on adequate input-to-output linearization and Lyapunov-based parameters adaptation scheme, with a view to track the reference model and compensate the system parametric variations. The outer voltage loop is set consequently, assuming fast inner loops dynamics. The proposed control law is designed in Simulink/Matlab and executed in real-time on a 1.5 kW laboratory prototype using the DS1104 controller board of dSPACE. The experimental results are given under various operating conditions, including steady state operation at different power levels, unbalanced DC load steps, temporary phase loss and -30% AC supply voltage dip/ swell. The proposed control law ensures low output voltage ripple, minimum AC line-current THD, small overshoots and fast settling times, face to a wide clan of disturbances.

Proceedings 2 20 01 12 2 I IE EE EE E I In nt te er rn na at ti io on na al l C Co on nf fe er re en nc ce e o on n C Co on nt tr ro ol l S Sy ys st te em m, , C Co om mp pu ut ti in ng g a an nd d E En ng gi in ne ee er ri in ng g (ICCSCE 2012) 23 -25 November 2012 P PA AR RK KR RO OY YA AL L P Pe en na an ng g R Re es so or rt t Batu Ferringhi, Penang Malaysia Organizer IEEE Control System Society Chapter Malaysia

A new method for power factor compensation of a three-phase bridge uncontrolled rectifier with a dc filter and nonlinear load is proposed. The method is based on the Rectifier with Near Sinusoidal Currents called RNSIC, which functions as power factor compensation in a wide range of load currents. The decrease of input currents harmonics, below the limits imposed by IEEE 519/1992 and IEC 61000-3-4 international standards, allows the decrease of THD, hence the increase in real power factor. Experimental results from prototypes bench are shown to confirm the validity of proposed method.

Este trabajo presenta el diseño, simulación e implementación de un transformador electrónico de baja potencia, cuya salida de voltaje efectivo se puede controlar de forma inalámbrica a través de WIFI, por medio de una interfaz de usuario en un teléfono móvil. La metodología usada en este proyecto está conformada por 4 etapas, un rectificador, un inversor, un sistema de control de los inversores y un reductor de ferrita. El inversor tiene un diseño de puente completo y se implementó utilizando MOSFET. El sistema de control puede variar la frecuencia y el ciclo de trabajo de las señales a la salida, cambiando de fase las señales de control, logrando así la funcionalidad de reducir el voltaje eficaz de salida. Se realizaron simulaciones del diseño circuital utilizando PsPice Orcad. Se realizó la implementación y el modelo matemático del transformador electrónico construido. El transformador diseñado opera con voltaje de entrada máximo de 120 Vrms a 60 Hz a frecuencias entre 20 kHz y 30 kHz, las cuales son controladas a través de la interfaz de usuario; puede reducir una señal de entrada de 120 Vrms 60 Hz a un voltaje eficaz entre 10 Vrms y 20 Vrms a una potencia máxima de 50 W. Este proyecto presenta la viabilidad de desarrollar transformadores electrónicos con voltaje de salida variable, controlados de forma remota por medio de tecnología IoT.

In this paper, a new approach to improve power factor and reduce harmonics generated by a three-phase diode rectifier type utility interface is proposed. The proposed approach is passive and consists of a novel interconnection of a s t a r / d e l t a transformer between the ac and dc sides of the diode rectifier topology (see ). This novel interconnection,

Control scheme of an Induction Generator (IG) associated with a wind turbine system. The turbine is used to drive the IG in order to feed an isolated DC load. It receives the required active power from the generator through a rectifier and a DC bus. The models of the system components are developed and used in the system control scheme. Mathematical relations treating the system components are presented and studied. The generator and the turbine dynamic performances are analyzed. The simulation results of the system entire control have shown that the proposed methodology is an efficient and promising control procedure. I.

This paper is an outcome of a wide research on RF energy harvesting techniques presented so far along with the development and implementation of the new idea of using a matching network with and without including parallel capacitance. While working with variable signal power in RF energy harvesting there is always a problem with nonlinear behavior of rectifying diode in harvesting circuit, to overcome the same a variety of matching networks are proposed in this manuscript with the variable RF power along with the variable load. Simulation results shows that output has been achieved upto 1.8Volts with maximum power conversion efficiency up to 79% at-10 dBm input power. Experimental results represented DC output of 1.62 volts at a frequency of 900 MHz with-10 dBm input power. Optimization technique is used to select parameters value which maximizes output voltage and efficiency. Variation of load resistance and input power plays a major role in output voltage and conversion efficiency. Comparison of the same is also presented in this particular research paper.

A new precise full-wave Rectifier by using non-linear applications of operational Amplifier circuit is In this article presented. By using an appropriate design for proposed op-amp circuit, this circuit is designed as the output is not saturated. A precise full-wave rectifier can be designed for high frequencies. The objective of the proposed circuit is more focused on minimum input voltage. In the structure of this rectifier op-amp circuit proposed is used, and for ideal diode, connec ted diode is used. Output voltage simulation has been done by using Hspice software in 0.18 um technology.