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1

FRACTIONAL ORDER SMC FOR DC-DC BUCK CONVERTER  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper proposed a fractional order sliding mode control for DC-DC buck converter. The traditionally P, PI and PID type linear controllers are used to control the voltages. The DC-DC buck converter is nonlinear and time variant in nature. To control such system variable structure control based sliding mode controller (SMC) is used. The fractional order sliding mode control method not only eliminates chattering problem of integer order SMC, it gives good transient response of the system. Th...

Jagdale, S. D.; Nagarale, R. M.

2013-01-01

2

Modeling and State Control of Switched Mode DC-DC Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper presents a design methodologyuseful to control DC-DC converters. As a practicalexample, the authors show how to design a controllerfor a switched mode DC-DC buck converter. Since theswitched mode power converters are nonlinear systems,the authors used the state space averaging techniquesto obtain a linear model for the buck converter. Theconverter operates in the steady state continuousconduction mode using the state control method. Incomparison with other control methods, such asvo...

Trip, Nistor Daniel; Popescu, Viorel; Dudrik, Jaroslav

2010-01-01

3

Charger for NiMH batteries based on buck DC/DC converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper is presented charger for NiMH battery types AA. Charger is realized by Buck DC/DC converter and microcontroller. Microcontroller controls the work of Buck DC/DC converter by pulse width modulation and by measuring the current of battery charging. The current of charging is held constant by power electronics, and the time of charging is set by the user dependent of capacity of the battery. Standard battery chargers enable the recharge of NiMH b...

Lap?evi? Vladimir

2014-01-01

4

A New Zero Voltage Switching Buck-Boost Type DC-DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a new zero voltage switching isolated buck-boost DC-DC converter with active clamp circuit is proposed. The active clamp circuit in this converter not only absorbs voltage spikes across the main switch but also provides soft switching conditions for all switches. All switches are PWM controlled which simplifies the control implementation. One of the main advantages of this converter is the that it operating can operate at high power levels while soft switching conditions exist ...

Majid Delshad

2010-01-01

5

Design of a PEM Fuel Cell Simulator Based on DC-DC Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Modeling of fuel cells is getting more and more important as power fuel cell stacks being available and have to be integrated into real power systems. This paper presents a novel circuit simulator for a PEM fuel cell that can be used to design fuel cell based systems. The simulator is consisted of a DC-DC buck converter driven by PIC 16F877 microcontroller. The proposed circuit can be used in design and analysis of fuel cell power systems.

Georgi Georgievski; Arsov, Goce L.

2010-01-01

6

Incremental Conductance MPPT Algorithm for PV System Implemented Using DC-DC Buck and Boost Converter  

Directory of Open Access Journals (Sweden)

Full Text Available The two basic topologies of switch mode DC-DC converters (Buck and Boost are analyzed with a view of their use in PV (photovoltaic systems, as the photovoltaic generator exhibits non-linear characteristics due to the change in environmental condition and load variation. As the efficiency of PV panels is low it becomes mandatory to extract maximum power from the PV panel at a given period of time. Several MPPT algorithms with different types of converters are being proposed for extracting maximum power from the PV panel. It is found that the nature of load plays an important role in the choice of topology. This paper investigates the implementation issues of Incremental Conductance method with Buck and Boost Converters. Mathematical analysis and desirable steady-state operating point of the converters are derived to give satisfactory maximum power point tracking operation.

Dhananjay Choudhary

2014-08-01

7

Existence of horseshoe maps in current-mode controlled buck-boost dc/dc converters  

International Nuclear Information System (INIS)

In this paper, a buck-boost dc/dc converter under a typical current-mode control is studied. The existence of chaos is proven theoretically in this system. The proof consists of showing that the dynamics of the system is semiconjugate to that of the one-sided shift map, which implies positive entropy of the system and hence chaotic behavior. The essential tool is the horseshoe hypotheses proposed by Kennedy and Yorke, which will be reviewed prior to the discussion of the main finding. Moreover, the existence of chaos is also illustrated in the light of homoclinic intersections of stable and unstable manifolds

8

A STUDY OF ADAPTIVE FEED FORWARD AND FEEDBACK CONTROL METHODS FOR SLIDING MODE CONTROLLED DC-DC BUCK CONVERTERS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Switching frequency acts as a major role, while applying sliding mode control to dc-dc buck converter, switching frequency is affected by line and load variations. To reduce switching frequency deviation to line and load variations, an adaptive feed forward control is used, that varies hysteresis band according to the change of input voltage. Several methods of varying hysteresis band of the hysteresis modulator are possible. In this work adjusting the power supply is to be considered. An ada...

Nagaraj, H. N.; Rajanna, G. S.

2012-01-01

9

Mission Profile Based Optimization of a Synchronous-Buck DC-DC Converter for a Wearable Power System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A Wearable Power System (WPS) is a portable fuel-to-electrical energy converter that is carried on the body and is able to supply an average of 20 W for 4 days and has a total weight of less than 4 kg. Due to limited total weight of the system, each system part must have the highest efficiency to weight ratio. This paper presents the optimization of a synchronous buck DC-DC converter that is used to regulate the variable power source to a constant 14 VDC for the load. Higher switching frequen...

Vasic, Miroslav; Round, S. D.; Biela, J.; Kolar, J. W.

2009-01-01

10

Identifier-based adaptive neural dynamic surface control for uncertain DC-DC buck converter system with input constraint  

Science.gov (United States)

In this paper, an identifier-based adaptive neural dynamic surface control (IANDSC) is proposed for the uncertain DC-DC buck converter system with input constraint. Based on the analysis of the effect of input constraint in the buck converter, the neural network compensator is employed to ensure the controller output within the permissible range. Subsequently, the constrained adaptive control scheme combined with the neural network compensator is developed for the buck converter with uncertain load current. In this scheme, a newly presented finite-time identifier is utilized to accelerate the parameter tuning process and to heighten the accuracy of parameter estimation. By utilizing the adaptive dynamic surface control (ADSC) technique, the problem of "explosion of complexity" inherently in the traditional adaptive backstepping design can be overcome. The proposed control law can guarantee the uniformly ultimate boundedness of all signals in the closed-loop system via Lyapunov synthesis. Numerical simulations are provided to illustrate the effectiveness of the proposed control method.

Chen, Qiang; Ren, Xuemei; Oliver, Jesus Angel

2012-04-01

11

Radiation effects on DC-DC Converters  

Science.gov (United States)

DC-DC switching converters are circuits that can be used to convert a DC voltage of one value to another by switching action. They are increasing being used in space systems. Most of the popular DC-DC switching converters utilize power MOSFETs. However power MOSFETs, when subjected to radiation, are susceptible to degradation of device characteristics or catastrophic failure. This work focuses on the effects of total ionizing dose on converter performance. Four fundamental switching converters (buck converter, buck-boost converter, cuk converter, and flyback converter) were built using Harris IRF250 power MOSFETs. These converters were designed for converting an input of 60 volts to an output of about 12 volts with a switching frequency of 100 kHz. The four converters were irradiated with a Co-60 gamma source at dose rate of 217 rad/min. The performances of the four converters were examined during the exposure to the radiation. The experimental results show that the output voltage of the converters increases as total dose increases. However, the increases of the output voltage were different for the four different converters, with the buck converter and cuk converter the highest and the flyback converter the lowest. We observed significant increases in output voltage for cuk converter at a total dose of 24 krad (si).

Zhang, Dexin; Attia, John O.; Kankam, Mark D. (Technical Monitor)

2000-01-01

12

SIMPLIFIED APPROACHES FOR CONTROLLING DC-DC POWER CONVERTERS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper represents the design procedures of different compensation schemes for voltage mode controlled (VMC) dc–dc switching converters. Proportional integral derivative (PID) controllers, Fuzzy logic controllers (FLC), parallel combination of PID and FLC, and FLC tuned by PI controller have been investigated. MATLAB software is used to depict the buck converter performance with each compensator type when it is electrically simulated, and analytically modeled using its equivalent transfe...

Abdel Aziz, M. M.; Mahfouz, A. A.; Khorshied, D. M.

2012-01-01

13

Local Bifurcations in DC-DC Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Three local bifurcations in DC-DC converters are reviewed. They are period-doubling bifurcation, saddle-node bifurcation, and Neimark bifurcation. A general sampled-data model is employed to study the types of loss of stability of the nominal (periodic) solution and their connection with local bifurcations. More accurate prediction of instability and bifurcation than using the averaging approach is obtained. Examples of bifurcations associated with instabilities in DC-DC con...

Fang, Chung-chieh; Abed, Eyad H.

2012-01-01

14

Hysteretic Current Controlled Zvs Dc/Dc Converter For Automobile  

DEFF Research Database (Denmark)

A novel bi-directional dc-dc converter with ZVS and interleaving for dual voltage systems in automobiles is presented. A variable frequency extended band hysteretic current control method is proposed. In comparison with classical fixed frequency current control PWM, the reverse polarity peak current needed for ZVS operation is kept constant and no in excess circulating current losses at light load conditions are encountered. Inductor current ripple decreases with load reduction. Automatic changes in operation between buck and boost modes are accomplished without transient currents. Power circuit elements design is given. The four-stage interleaving is digitally controlled.

Cernat, M.; Scortarul, P.

2007-01-01

15

Fuzzy controlled resonant DC-DC converters  

Energy Technology Data Exchange (ETDEWEB)

The main purpose of the paper is to demonstrate the powerful property of a fuzzy inversion technique described earlier. A member of a new generation of a resonant DC-DC converter family is selected as controlled object. It is a dual channel step down converter. To demonstrate the powerful property of a fuzzy inversion technique, an adaptive fuzzy control algorithm was designed, and succesfully applied in simulation environment. Effectiveness of control theory applying the approximation of the inverse model is proved through results of simulation. (orig.)

Denes, I.; Szemes, P. [Technical Univ. of Budapest, Dept. of Automation (Hungary)

2000-07-01

16

HYBRID MODELING OF OPEN LOOP DC-DC CONVERTERS  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english Power electronic converters always have been circuits of difficult modelling because differential equations that describe them have discontinuities. Although this situation has been improved since the appearance of the Hybrid Systems theory, able to jointly describe both continuous and discrete beha [...] viors exhibited by some physical systems, nowadays it is possible to obtain very precise models which help us in the study and design of such circuits. An excellent option for the discrete part model (reactive system) is to use statecharts, since this powerful language has recently been implemented and named Stateflow as a part of the Simulink toolbox of Matlab. So, today, the complete modeling of some hybrid systems within Matlab environment is possible. In this work the open loop hybrid modeling and simulation of the well-known dc-dc converters named buck and boost, using Matlab-Simulink-Stateflow, is presented

Ekaitz, Zulueta; Teodoro, Rico; José María, González de Durana.

2003-12-01

17

SIMPLIFIED APPROACHES FOR CONTROLLING DC-DC POWER CONVERTERS  

Directory of Open Access Journals (Sweden)

Full Text Available This paper represents the design procedures of different compensation schemes for voltage mode controlled (VMC dc–dc switching converters. Proportional integral derivative (PID controllers, Fuzzy logic controllers (FLC, parallel combination of PID and FLC, and FLC tuned by PI controller have been investigated. MATLAB software is used to depict the buck converter performance with each compensator type when it is electrically simulated, and analytically modeled using its equivalent transfer function (TF. The comparative study Resultsemphasize that FLC tuned by PI controller is superior to the other control strategies because of fast transient response, minimum steady state error and good disturbance rejection under various variations of the operating conditions. Hence, it achieves the most tightly output voltage regulation.

M. M. ABDEL AZIZ

2012-02-01

18

High voltage conversion ratio, switched C & L cells, step-down DC-DC converter  

DEFF Research Database (Denmark)

The paper presents a high voltage conversion ratio DC-DC step-down topology obtained from a classical buck converter associated with an input switched-capacitor cell and an output switched-inductor cell. Analytical descriptions, the voltage and current limits of the main components are synthesized in a comparative form, related to the classical buck structure, in order to emphasis the advantages of the proposed converter. Digital simulations and experimental results obtained with a built prototype are compared. From the first evaluation, the proposed converter is expected to be effectively used at input to output voltage ratios higher than 20.

Pelan, Ovidiu; Muntean, Nicolae

2013-01-01

19

Transformerless High Step-Up Dc-Dc Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper proposes a transformer-less high step-up DC-DC converter which acts as an interconnection between DC systems. A new step up converter proposed in the paper is designed and simulated in a simulation environment. The conventional boost converter cannot have any control over the input current at a high duty cycle. Due to which, it draws considerable amount of current from the source which can create problems for the components used in DC-DC converter. Moreover, the voltage stress acro...

Surjagade, Amit S.; Bankar, Akshay B.; Rothe, J. P.

2014-01-01

20

Modified Multiport Dc-Dc Converter Topology For Smart Grid  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The development of a Solid State Transformer (SST) that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV) power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad active-bridge (QAB) converter which not only provides isolation for the load, but also for the PV and storage. The AC-DC stage is implemented with a pulse-widthmodulated (PWM) single phase rectifier. A unified gyrator-based average model is develope...

Dhamodharan Shanmugam

2013-01-01

 
 
 
 
21

Modeling of Linear-Assisted DC-DC Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper shows the modeling of a linear–assisted or hybrid (linear & switching) DC–DC converters. In this kind of converters, an auxiliary linear regulator is used, which objective is to cancel the ripple at the output voltage and provide fast responses for load variations. On the other hand, a switching converter, connected in parallel with the linear regulator, allows to supply almost the whole output current demanded by the load. The objective of this topology is to take advantage of...

Marti?nez Garci?a, Herminio; Conesa Roca, Alfons

2007-01-01

22

Sliding Mode Control of Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

DC-DC converters are used to convert DC voltage from one level to other. These converters are drastically used in industry as well as in research. One of the main limitations of these converters is unregulated supply of voltage and current. To overcome these problems there are various control techniques. This paper presents two such methods. This paper compares dynamic performance of buck Converter using PID controller and Sliding mode controller. Simulation of PI and Sliding mode control ...

Nagulapati Kiran

2014-01-01

23

High-Conversion-Ratio Bidirectional DC–DC Converter With Dual Coupled Inductors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a high-conversion-ratio bidirectional DC–DC converter with dual coupled inductors is proposed. In the boost mode, two capacitors are parallel charged and series discharged by the dual coupled inductors. Thus, high step-up voltage gain can be achieved with an appropriate duty ratio. In the buck mode, two capacitors are series charged and parallel discharged by the dual coupled inductors. The bidirectional converter can have high step-down voltage gain. The stress voltage of al...

Omid Khezri; Javad Javidan

2014-01-01

24

High Efficiency Interleaved Bi-Directional ZVS DC-DC Converter  

DEFF Research Database (Denmark)

A High Efficiency Interleaved Bi-Directional ZVS DC-DC converter is presented in this paper. This converter can be operated in both buck and boost mode. CoolMOS is used as a power device to achieve low conduction losses and fast turn off. The value of inductance is selected such that the CoolMOS drain-to-source voltage always falls to zero before it turns on and ZVS is achieved. Multiphase interleaved inductors are used to achieve high power and low ripple currents. Converter is operated at 50kHz and MATLAB Simulink simulation is performed. 6kW prototype converter is implemented in buck mode and simulation results are verified.

Zafar Ullah Khan, M.; Mohsin Naveed, M.

2013-01-01

25

A Pedagogical Approach for Modeling and Simulation of Switching Mode DC-DC Converters for Power Electronics Course  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The power electronics course is a rather challenging subject for instructors and undergraduate students pursuing Bachelor’s Degree in Electrical Engineering. To enhance teaching effectiveness and motivate self-learning capabilities of the students, this paper presents a pedagogical approach for mathematical modeling and simulation of switching mode DC-DC converters. The Buck and Boost converters are analyzed as benchmark systems to study the power converter modeling methodologies. And a...

Han Yang

2012-01-01

26

1.2 MW dc-dc converter  

Science.gov (United States)

A dc-dc converter has been developed to charge capacitors to 16 kV from a 400 V battery bank. It is designed to charge an 8.5 MJ bank nine times in 3 min. The converter is comprised of six modules, each producing 12.5 A of charging current, and an enclosure which houses the modules and provides control power and a master controller. The six 200 kW modules have a combined power rating of 1.2 MW. The pulse width modulation converter system operates at 24 kHz and contains inverters with power MOSFETs as the principal inverter components, 200 kW transformers and inductors, and full bridge rectifiers with fast recovery diodes. The converter modules have a volume power density of 1.0 MW/cu m and a mass power density of 1.2 kW/kg. The converter design and test results are described.

Homeyer, W. G.; Callanan, R. J.; Bowles, E. E.; Nerem, A.

1993-01-01

27

Performance Analysis Of Sensored And Sensorless Drive Of Bldc Motor Using Different Types Of Dc/Dc Converters In Matlab/ Simulink Platform  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract This paper presents a scheme for implementing two different DC/DC converters in the commutation circuitry of BLDC motor drive and corresponding output characteristic in both sensored and sensorless drive. Here we have considered Buck and Boost converters in order to provide a regulated supply to the commutation circuitry. The drive circuit is a closed loop system with a PI controller, Six-Switch Voltage Source Inverter (VSI) and one of the DC/DC converters among Buck and Boost. The p...

Sharda Jaiswal; Debjyoti Chowdhury; Madhurima Chattopadhyay

2014-01-01

28

Bi-Directional DC-DC Converter for PHEV Applications  

Energy Technology Data Exchange (ETDEWEB)

Plug-In Hybrid Electric Vehicles (PHEV) require high power density energy storage system (ESS) for hybrid operation and high energy density ESS for Electric Vehicle (EV) mode range. However, ESS technologies to maximize power density and energy density simultaneously are not commercially feasible. The use of bi-directional DC-DC converter allows use of multiple energy storage, and the flexible DC-link voltages can enhance the system efficiency and reduce component sizing. This will improve fuel consumption, increase the EV mode range, reduce the total weight, reduce battery initial and life cycle cost, and provide flexibility in system design.

Abas Goodarzi

2011-01-31

29

Direct switching control of DC-DC power electronic converters using hybrid system theory  

Energy Technology Data Exchange (ETDEWEB)

A direct switching control (DSC) scheme for power electronics converters was described. The system was designed for use in both traditional and renewable energy applications as well as in electric drive vehicles. The proposed control scheme was based on a detailed hybrid system converter model that used model predictive control (MPC), piecewise affine (PWA) approximations and constrained optimal control methods. A DC-DC converter was modelled as a hybrid machine. Switching among different modes of the DC-DC converter were modelled as discrete events controlled by the hybrid controller. The modelling scheme was applied to a Buck converter. The DSC was used to control the switch of the power converter based on a hybrid machine model. Results of the study showed that the method can be used to regulate output voltage and inductor currents. The method also provides fast transient responses and effectively regulates both currents and voltage. The controller can be used to provide immediate responses to dynamic disturbances and output voltage fluctuations. 23 refs., 7 figs.

Zhao, J.; Lin, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wang, C. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wayne State Univ., Detroit, MI (United States). Div. of Engineering Technology

2010-07-01

30

Buck Converter Animation  

Science.gov (United States)

This website from the Thayer School of Engineering at Dartmouth College features an animation of a buck converter. A buck converter is a step-down DC to DC converter. Its design is similar to the step-up boost converter, and like the boost converter it is a switched-mode power supply that uses two switches (a transistor and a diode), an inductor and a capacitor.

31

High Efficiency Interleaved Active Clamped Dc-Dc Converter with Fuel Cell for High Voltage Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A high efficiency interleaved ZVS active clamped current fed dc-dc converter is proposed in this paper specially used for fuel cell applications. As the fuel cell output is very low we are in need of a step up dc-dc converter. Here a current fed dc-dc converter is used. Two current fed dc-dc converters are interleaved by connecting their inputs in parallel and outputs in series. With this proposed methodology input current ripples in the fuel cell stacks can be reduced and a re...

Sona P.; Sheela Joseph

2014-01-01

32

Buck Converter Design Issues  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Switch Mode Power Supplies are very important components in present day electronics and have continued to thrive and grow over the past 25 years. This thesis looks inside how the SMPS have evolved over the passage of years with special emphasis to the Synchronous Buck Converter. It also discusses why there is a strong potential to further the study related to designs based around a Synchronous Buck Converter for portable applications. The main objective of the thesis is to look into the contr...

Rahman, Muhammad Saad

2007-01-01

33

Power Network impedance effects on noise emission of DC-DC converters  

Science.gov (United States)

The characterization of electromagnetic noise emissions of DC-DC converters is a critical issue that has been analyzed during the desing phase of CMS tracker upgrade. Previous simulation studies showed important variations in the level of conducted emissions when DC-DC converters are loaded/driven by different impedances and power network topologies. Several tests have been performed on real DC-DC converters to validate the Pspice model and simulation results. This paper presents these test results. Conducted noise emissions at the input and at the output terminals of DC-DC converters has been measured for different types of power and FEE impedances. Special attention has been paid to influence on the common-mode emissions by the carbon fiber material used to build the mechanical structure of the central detector. These study results show important recommendations and criteria to be applied in order to decrease the system noise level when integrating the DC-DC.

Esteban, M. C.; Arteche, F.; Iglesias, M.; Gimeno, A.; Arcega, F. J.; Johnson, M.; Cooper, W. E.

2012-01-01

34

Discontinuous Buck Converter  

Science.gov (United States)

This animation, created by faculty at Dartmouth University, is a discontinuous buck converter. The resource features other animations such as boost and discontinuous converters. They also add simple diode, bridge and half-wave rectifiers. Although simple in design, this can still be a useful resource for those interested in electrical engineering.

35

Performance of a Voltage Step-Up/Step-Down Transformerless DC/DC Converter: Analytical Model  

Science.gov (United States)

The authors present an analytical model for a voltage step-up/step-down DC/DC converter without transformers. The proposed topology is a combination of classic buck and boost converters in one single circuit but with differing operational principles. The converter is developed for a wind power autonomous supply system equipped with a hydrogen electrolytic tank and a fuel cell for energy stabilization. The main power source of the hydrogen-based autonomous supply system is energized by a synchronous generator operating on permanent magnets and equipped with a diode bridge. The input voltage of the converter in this case varies in the range 0-700 V, while its output DC voltage must be 540 V according to the demand of other parts of the system. To maintain the rated voltage, a special electrical load regulation is introduced. The calculations of the converter, the generator (equipped with a diode bridge) as element of the power system supply joint, and the load replaced by resistance are verified with PSIM software.

Suskis, P.; Rankis, I.

2012-01-01

36

Design and Implementation of a FLC for DC-DC Converter in a Microcontroller for PV System  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the design and implementation of a simple fuzzy logic controller (FLC for a DC-DC buck converter based on the PIC18F4550 microcontroller to control the lead acid battery charging voltage in solar cells applications. For cost consideration, an inexpensive 8-bit microcontroller is selected to program and implement the FLC proportional-integral. The obtained simulation and experimental results show the viability of the controller with a variation on the load of the buck converter showing a good performance on the design of the FLC, and it has also a smooth response with a small overshoot. The DC-DC converter designed in this work can be found applications in low cost photovoltaic (PV systems, although in the literature has been already reported this kind of devices with a better response [3-4], however these use a expensive microcontroller or its designs are very complex, and where these are not necessary for this kind of applications. Finally, a prototype PV system with 100 V/6 A has been implemented for verifying the feasibility of the CD-CD converter.

Abel García-B.

2013-07-01

37

DC/DC Power Converter for Super-Capacitor Supplied by Electric Power Splitter  

Science.gov (United States)

The aim of the article is design of DC/DC converter and discussing of problematic supply using electric power splitter. The electric power splitter with AC/DC converter is source for the DC/DC converter, which is dedicated for charging and discharging of hybrid car drive super-capacitor energy storage. The electric power splitter is synchronous machine with two rotating parts. First rotor contains permanent magnet and the second rotor contains three-phase windings. The amplitude of output voltage depends on difference between first and second rotor speed. The main role of the DC/DC converter is to optimize energy content in super-capacitor storage used to acceleration and deceleration driving period of the passenger car with hybrid electric vehicle (HEV) drive system using electric power splitter.

Haubert, T.; Mindl, P.

38

PHOTOVOLTAIC BASED HIGH-EFFICIENCY SINGLE-INPUT MULTIPLE-OUTPUT DC-DC CONVERTER  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this paper is to develop a photo voltaic power generation based high-efficiency multiple-output dc–dc converter. The proposed converter can boost the voltage of a low-voltage input power source to a controllable high-voltage dc bus and middle-voltage output terminals. In this paper, a coupled-inductor based dc–dc converter scheme utilizes only one power switch with the properties of voltage clamping and soft switching, and the corresponding device specifications are adequately ...

Kondalaiah?, J.; Rahul?, I.

2014-01-01

39

Experimental study of dynamic behaviors and routes to chaos in DC-DC boost converters  

International Nuclear Information System (INIS)

This paper illustrates an experimental study of a current-programmed DC-DC boost converter, with the aim of investigating possible pathways through which the converter may enter chaos. In particular, based on experimental measurements, it is shown that variations of input voltage and reference current can generate periodic, subharmonic, quasi-periodic and chaotic behaviors

40

Single Event Burnout in DC-DC Converters for the LHC Experiments  

Energy Technology Data Exchange (ETDEWEB)

High voltage transistors in DC-DC converters are prone to catastrophic Single Event Burnout in the LHC radiation environment. This paper presents a systematic methodology to analyze single event effects sensitivity in converters and proposes solutions based on de-rating input voltage and output current or voltage.

Claudio H. Rivetta et al.

2001-09-24

 
 
 
 
41

Modelling, simulation and construction of a dc/dc boost power converter: a school experimental system  

Science.gov (United States)

We introduce a dc/dc boost power converter as a didactic prototype intended to support courses on electric circuit analysis experimentally. The corresponding mathematical model is obtained, the converter is designed and an experimental setup is described, constructed and tested. Simplicity of construction as well as low cost of components renders the feasible introduction of this equipment in undergraduate laboratories.

Silva-Ortigoza, R.; Silva-Ortigoza, G.; Hernández-Guzmán, V. M.; Saldaña-González, G.; Marcelino-Aranda, M.; Marciano-Melchor, M.

2012-05-01

42

Buck-boost converter with fractional control for electric vehicles  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, non-integer order control is applied to improve the performance of a buck-boost dc-dc power converter with ultracapacitor based on state feedback techniques. The approach is based on stabilization in the Lyapunov's sense for linear rational-order systems. The ultracapacitor can overcome the classical problems of energy losses due to the use of batteries, giving more accuracy, autonomy and efficiency to the electrical vehicles.

Marti?nez Gonza?lez, Rube?n; Bolea Monte, Yolanda; Grau Saldes, Antoni; Marti?nez Garci?a, Herminio

2010-01-01

43

DC/DC converters for integration of double-layer condensers in onboard power supply; DC/DC-Wandler zur Einbindung von Doppelschichtkondensatoren in das Fahrzeugenergiebordnetz  

Energy Technology Data Exchange (ETDEWEB)

The paper discusses DC/DC converters for integration of double layer condensers into the onboard power system. First, requirements on DC/DC converters are listed and compared on the basis of three exemplary applications. A DC/DC converter concept is developed for decoupling transient high-power loads like electric steering systems. Three different topologies are compared using a specially developed method in order to find the best solution for the given application. In order to establish adequate criteria for selecting the switching frequency and inductivities of storage throttles, the influence of the trottle power change on the switching characteristics of the MOSFETs and on certain ranges of EMP interference emissions is investigated. As methods of optimising the operation of the synchronous rectifiers, parallel connection of Schottky diodes and synchronous rectifiers as well as the variation of the shut-off dead times of synchronous rectifiers were investigated. Further, a concept for converter control was developed in consideration of the intended application and topology. Finally, selected aspects for implementation of the DC/DC converter concept are presented as well as the results of experimental investigations.

Polenov, Dieter

2010-01-15

44

Soft Switched Multi-Output PWM DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a new soft switched cell that overcomes most of the drawbacks of the normal "hard switched-pulse width modulation" converter is proposed to contrive a new family of soft switched PWM converters. All of the semiconductor devices in this converter are turned on and off under exact or near zero voltage switching (ZVS and/or zero current switching (ZCS. No additional voltage and current stresses on the main switch and main diode occur. A push-pull converter equipped with the proposed snubber cell is analyzed in detail. The predicted operation principles and theoretical analysis of the presented converter are verified with a prototype of a 50W PWM push-pull multi-output converter with insulated MOSFET and for regulation of slave outputs magnetic amplifier post regulators are considered as post regulators. Moreover; this multioutput converter has a simple structure, low cost, and ease of control circuitry.

Rashmi Sharma

2013-07-01

45

Multi-Level DC-DC Converter for High Gain Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The output voltage from most renewable energy sources like photovoltaic arrays and fuel cells will be at low level. This must be stepped up considerably for practical utilization or grid connection. The presented multilevel boost converter DC-DC converter topology consists of the conventional boost converter and voltage doubler stages to provide high voltage gain. The proposed topology uses only one switch along with one inductor, (2N-1) diodes and (2N-1) capacitors for obtaining an output wh...

Girish Ganesan R; Prabhakar, M.

2013-01-01

46

A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase-shift modulation scheme, all the switches can realize zero-voltageswitching (ZVS) turn-on and bidirectional power flow can be controlled with phase-shift angle. The operating principles of the converter are descr...

Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.

2009-01-01

47

A DC-DC Converter with Wide Input Voltage Range for Fuel Cell and Supercapacitor Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper proposes a novel phase-shift plus duty cycle controlled hybrid bi-directional DC-DC converter based on fuel cells and supercapacitors. The described converter employs two high frequency transformers to couple the half-bridge and full-bridge circuits together in the primary side and voltage doubler circuit in secondary side. Boost type converter can limit the output ripple current of the fuel cells; hybrid full-bridge structure can change operating modes according to the differen...

Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.

2009-01-01

48

A High Voltage-lift Efficient Isolated Full Bridge DC-DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this study is to propose a high voltage lift isolated full bridge dc-dc converter. The proposed converter consists of an isolation transformer a low turn ratio to obtain high step up voltage gain. The secondary of the transformer connected with two boosting capacitors which connects parallel when power switches switch on period and discharged in series during the switch off period. In addition full bridge converter on primary side consists of clamping diode and capacitor, leakage e...

Gopi, A.; Saravanakumar, R.

2014-01-01

49

Symmetrical multilevel converters with two quadrant DC-DC feeding  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the technology sector of power electronics and control, the multilevel converter technology is still a rather new research area, but the application possibilities in the field of power drives and energy will demand more solutions with this promising technology. In the future, more converter systems will be realized with the multilevel topology. Up to now, multilevel converters have only been used in very particular applications, mainly due to the high costs and complexity of the multilevel...

Schibli, Nikolaus

2000-01-01

50

Full Wave Mode ZVT-PWM DC-DC Converters  

Energy Technology Data Exchange (ETDEWEB)

This paper proposes a full wave model ZVT-PWM boost converter. The converter with the auxiliary switch in a full wave mode makes possible soft switching operation of all switches including the auxiliary switch whereas the auxiliary switch is turned of with hard switching in the conventional converter. Therefore, the proposed converter reduces the turn-off switching loss and switching noise of the auxiliary switch without additional passive and/or active elements and high power density system can be realized. (author). 5 refs., 10 figs., 2 tabs.

Kim, Tae Woo; Ahn, Hee Wook; Kim, Hack Sung [Kumoh National University of Technology, Kumi (Korea)

2001-06-01

51

Pulse-width modulated DC-DC power converters  

CERN Document Server

This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,

Kazimierczuk, Marian K

2008-01-01

52

Monolithic Magnetic Modules for DC-DC Power Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Advances in planar magnetic technology have resulted in the development of high speed, high power density, magnetic components for use in electrical power converters. In particular, the use of such components will result in a substantial reduction in transformer and inductor volumes, and will encourage development of low-profile, lightweight, efficient power converters that conform readily to printed circuit topologies. This paper describes a single, plasma-spray fabrication process, which ov...

Varshney, U.; Davis Eichelberger Iii, B.; Neal, J.; Churchill, R.; Ngo, K.; Thibodeaux, R.

1997-01-01

53

High-Temperature SOI/SiC-Based DC-DC Converter Suite  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A complete design strategy (mechanical and electrical) for a 25 W 28 V/5 V dc-dc converter utilizing SiC and SOI electronics is presented. The converter includes a high-temperature SOI-based PWM controller featuring 150 kHz operation, a PID feedback loop, maximum duty cycle limit, complementary or symmetrical outputs, and a bootstrapped high-side gate driver. Several...

Lostetter, Alexander B.; Schupbach, Roberto M.; Jared Hornberger; Robert Shaw; Brice McPherson; Reese, Bradley A.

2008-01-01

54

Adaptive Non-singular Terminal Sliding Mode Control for DC-DC Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

DC-DC converters have some inherent characteristics such as high nonlinearity and time-variation, which often result in some difficulties in designing control schemes. An adaptive non-singular terminal sliding mode control method is presented in this paper. Non-singular terminal sliding mode control is used to make the converter reach steady state within a limited time, and an adaptive law is integrated to the non-singular terminal sliding mode control scheme to make the proposed control me...

Yu, Y.; Fan, L.

2011-01-01

55

LPV model for PV cell and fractional control of DC/DC converter for photovoltaic systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper deals with the fractional modelling of a DC-DC converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. A new model for PV cells is proposed in order to obtain a linear equation for V-I characteristic via scheduling dependence of temperature and irradiance. Due to the fractional nature of the ultracapacitors this kind of controller gives a suitable and good performance.

Marti?nez Gonza?lez, Rube?n; Bolea Monte, Yolanda; Grau Saldes, Antoni; Marti?nez Garci?a, Herminio

2011-01-01

56

Real-time hybrid model predictive control of switched dc-dc converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this research, a new method to control switching in dc-dc converters is presented using recent advances in hybrid optimal control theory. Herein, the switched state model of the converter is embedded into a continuously parameterized family of problems, and an embedded optimal control problem (EOCP) is formulated as the minimization of a user-defined performance index (PI). Solution of the EOCP produces a single (“optimal”) duty cycle control for each switch period which is implemented...

Neely, Jason C.

2010-01-01

57

High Step-Up DC-DC Converter for Distributed Generation System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study proposes a method which consists of High step up DC-DC converter with a coupled inductor for distributed generation system. Theoretically the conventional boost converter provides high step up voltage gain but in practical it is limited by reverse recovery problem of diode, effective series impedance of inductors and capacitors and switching losses. High charged current and conduction losses occur in the switch when voltage lift and switched capacitor techniques are used. In the pr...

Jayakrishnan, V. K.; Sarin, M. V.; Archana, K.; Elangovan, D.; Saravanakumar, R.; Praveen Kumar, M.

2013-01-01

58

Current-Steering Switching Policy for a SIDO Linear-Assisted Hysteretic DC/DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper proposes the use of linear-assisted switching power converters in the context of single-inductor dual-output (SIDO) applications. By combining a DC/DC ripplecontrolled switching power converter with the respective voltage linear regulators at each output, improved performance in terms of load and line regulations is obtained. To achieve that aim, a current-steering switching policy is proposed, together with a resource-aware circuit implementation. The ripple-based hysteretic...

Marti?nez Garci?a, Herminio; Silva-marti?nez, Jose?; Alarco?n Cot, Eduardo Jose?; Poveda Lo?pez, Alberto

2010-01-01

59

Bidirectional buck boost converter  

Science.gov (United States)

A bidirectional buck boost converter and method of operating the same allows regulation of power flow between first and second voltage sources in which the voltage level at each source is subject to change and power flow is independent of relative voltage levels. In one embodiment, the converter is designed for hard switching while another embodiment implements soft switching of the switching devices. In both embodiments, first and second switching devices are serially coupled between a relatively positive terminal and a relatively negative terminal of a first voltage source with third and fourth switching devices serially coupled between a relatively positive terminal and a relatively negative terminal of a second voltage source. A free-wheeling diode is coupled, respectively, in parallel opposition with respective ones of the switching devices. An inductor is coupled between a junction of the first and second switching devices and a junction of the third and fourth switching devices. Gating pulses supplied by a gating circuit selectively enable operation of the switching devices for transferring power between the voltage sources. In the second embodiment, each switching device is shunted by a capacitor and the switching devices are operated when voltage across the device is substantially zero.

Esser, Albert Andreas Maria (Niskayuna, NY)

1998-03-31

60

Soft switching DC/DC converter using auxiliary circuits  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.

Jaroslav Dudrik; Vladimír Ruš?in

2008-01-01

 
 
 
 
61

SUBCONTRACT REPORT: DC-DC Converter for Fuel Cell and Hybrid Vehicles  

Energy Technology Data Exchange (ETDEWEB)

The goal of this project is to develop and fabricate a 5kW dc-dc converter with a baseline 14V output capability for fuel cell and hybrid vehicles. The major objectives for this dc-dc converter technology are to meet: Higher efficiency (92%); High coolant temperature,e capability (105 C); High reliability (15 Years/150,000miles); Smaller volume (5L); Lower weight (6kg); and Lower cost ($75/kW). The key technical challenge for these converters is the 105 C coolant temperatures. The power switches and magnetics must be designed to sustain these operating temperatures reliably, without a large cost/mass/volume penalty.

Marlino, Laura D [ORNL; Zhu, Lizhi [Ballard Power Systems/Siemens VDO

2007-07-01

62

High Step Up Dc-Dc Converter For Non-Conventional Energy Source  

Directory of Open Access Journals (Sweden)

Full Text Available The demand for non-isolated high step-up dc–dc converters in applications such as dc backup energy systems for UPS, photovoltaicand fuel cell systems, and hybrid electric vehicles has been gradually increasing. This project proposes a non-isolated step-up dc–dc converter with an improved switching method. The proposed converter shows zero-voltage switching turn-on of the switches in continuous conduction mode as well as reduced turnoff switching losses using resonant PWM.As a result of the proposed switching method, the switching losses associated with diode reverse recovery become negligible even in the small duty cycle. The capacitance in the auxiliary circuit is significantly reduced compared to the pulse width modulation method. The duty cycle loss is further reduced resulting in increased step-up ratio.The result of the project is implemented in Simulation using MATLAB Simulink Software.

K. Kuralanban

2013-04-01

63

Design & Implementation of Zero Voltage Switching Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Zero voltage switching (ZVS buck converter is more preferable over hard switched buck converter for low power, high frequency DC-DC conversion applications. In Zero voltage switching converter, turn on & turn off of a switch occurs at zero voltage that results in lower switching losses. In this converter soft switching is achieved by using resonant components. The optimal values of resonant components are determined by using electric functions derived from circuit configuration. This type of soft switched resonant converter offers very low electromagnetic interference (EMI.This study presents the circuit configuration with least components to realize highly efficient zero voltage switching resonant converter. It’s feasibility is confirmed with the developed proto type model and experimental results are verified.

A.Suresh Kumar

2014-09-01

64

Isolated Bidirectional DC–DC Converter for SuperCapacitor Applications  

DEFF Research Database (Denmark)

This paper proposes a new bidirectional DC/DC converter for supercapacitor applications. The proposed converter has a parallel structure in supercapacitor side (where voltage is low and current is high) and a series structure in the other side. This structure increases efficiency of the converter. For current sharing in the parallel side of the proposed converter, two different methods are recommended and compared in this paper: Current balancing transformer (CBT) and two separate inductors (TSI). Simulation and experimental results show performance of the proposed converter.

Dehnavi, Sayed M. D.; Sen, Gökhan

2011-01-01

65

Optimization of Shielded PCB Air-Core Toroids for High-Efficiency DC-DC Converters  

CERN Document Server

The paper describes the design of optimized printed circuit board (PCB) air-core toroids for high-frequency dc-dc converters with strict requirements in terms of volume and noise. The effect of several design parameters on the overall inductor volume, on dc and ac winding resistance, and on the radiated noise will be investigated. PCB toroids are compared to standard air-core solenoids and other state-of-the-art air-core toroids both theoretically and experimentally: at first, using ANSOFT Maxwell and ANSOFT Q3D simulation tools, and subsequently, with laboratory measurements (irradiated noise, efficiency, and frequency response) on several prototypes. These very flexible and rather easy to manufacture inductors appear very attractive for compact high-frequency dc-dc converters where high efficiency, low volume, and low noise are of primary concern.

Orlandi, S; Buso, S; Michelis, S; Fuentes, C A; Kayal, M; Faccio, F; Spiazzi, G

2011-01-01

66

Dynamic Modelling & Controller Design for Z-Source DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the detailed mathematical modeling of Z-source dc-dc converter (ZSC in continuous conduction mode. Transfer function of ZSC is derived based on mathematical modeling with state space averaging method. This paper has been focused on dynamic modeling of open loop transfer function of ZSC along with design of closed loop controller. MATLAB based simulation results are presented for open loop and close loop system of ZSC.

Shilpa Sarode

2013-04-01

67

Synthesis of dissipative nonlinear controllers for series resonant DC/DC converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper describes analytical advances and practical experiences in a nonlinear controller design methodology for series resonant DC/DC converters. The control goal is to maintain the output voltage (which is the only measured variable) in the presence of large-load perturbations by varying the switching frequency. The proposed methodology utilizes large-scale, nonlinear switched, and generalized averaged models, and the resulting closed-loop system is exponentially convergent under typical...

Stankovic, Aleksandar M.; Perreault, David J.; Sato, Kenji

1998-01-01

68

High Efficiency Resonant DC/DC Converter Utilizing a Resistance Compression Network  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new topology for a high-efficiency dc/dc resonant power converter that utilizes a resistance compression network (RCN) to provide simultaneous zero-voltage switching and near-zero-current switching across a wide range of input voltage, output voltage, and power levels. The RCN maintains desired current waveforms over a wide range of voltage operating conditions. The use of ON/OFF control in conjunction with narrowband frequency control enables high efficiency to be maint...

Inam, Wardah; Perreault, David J.; Afridi, Khurram

2013-01-01

69

Design and Implementation of Digital Current Mode Controller for DC-DC Converters  

DEFF Research Database (Denmark)

In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required to be regulated by a closed-loop controller. The Peak Current Mode Control (PCMC) is one of the most promising control methods for dc-dc converters. It has been known for high bandwidth (speed), and inherent current protection. Increasing the controller bandwidth decreases the output filter size and cost. Analog controllers (including PCMC) are sensitive to temperature drift, component aging and noise. Digital controllers do not have the aforementioned drawbacks of analog controllers; but they have lower bandwidth than analog controllers due to the sampling and calculation delays. Generally, analog controllers have a bandwidth of 1/10 of the switching frequency. In the current state-of-the-art, the best reported digital PCMC hascrossover frequency of 1/15 of the switching frequency. In this PhD study a novel digital PCMC with negligible delay in the inner current loop has been proposed. The proposed solution has a bandwidth of 1/10 of the switching frequency; which is an improvement of 50% compared to the best reported digital solution, also the achieved crossover frequency is nearly equal to analog controller crossover frequency. Furthermore, the proposed solution offers an adaptive compensation slope; therefore the controlled converter can maintain a high bandwidth over wide range of the operating points. The proposed digital PCMC is modeled and the stability criteria are defined. The digital PCMC is implemented in a Field-Programmable Gate Array (FPGA). The experimental results verify the modeling method and the high predicted bandwidth of the proposed controller. Additionally, the small signal model of the isolated full-bridge boost converter is obtained and the modeling method is verified by experimental results. In modeling, the Equivalent Series Resistance (ESR) of the inductor and capacitor are also included. Analyzing the obtained model reveals that the small values of capacitor and inductor ESR results in a large resonance peak of complex poles in the voltage to duty cycle transfer function. High efficiency dc-dc converters essentially have low ESR in the capacitor and the inductor. Since the complex poles are eliminated in current mode control; applying the current mode control in high efficiency dc-dc converters results in much higher controller bandwidth.

Taeed, Fazel

2014-01-01

70

Modeling and Current Programmed Control of a Bidirectional Full Bridge DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Modelling of bidirectional full bridge DC-DC converter as one of the most applicable converters has received significant attention. Mathematical modelling reduces the simulation time in comparison with detailed circuit response; moreover it is convenient for controller design purpose. Due to simple and effective methodology, average state space is the most common method among the modelling methods. In this paper a bidirectional full bridge converter is modelled by average state space and for each mode of operations a controller is designed. Attained mathematical model results are in a close agreement with detailed circuit simulation.

Abdolreza Rahmati

2012-05-01

71

Modeling and Simulation of Sensorless Speed Control of a Buck Converter Controlled Dc Motor  

Directory of Open Access Journals (Sweden)

Full Text Available This paper investigate a sensorless speed control of a separately excited dc motor fed from a buck type dc-dc converter. The control system is designed in digital technique by using a two dimension look-up table. The performance of the drive system was evaluated by digital simulation using Simulink toolbox of Matlab.

Tagreed M. Ali

2010-01-01

72

Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to Obtain High DC Voltage  

Directory of Open Access Journals (Sweden)

Full Text Available In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with the use of nine stage Cockcroft-Walton (CW voltage multiplier. The proposed converter operates in CCM (continuous conduction mode, so that the converter switch stress, the switching losses are reduced. The DC voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls in DC-DC converter stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with low input pulsating DC (AC Voltage voltage where it is getting converted to high DC output voltage. The proposed converter switches operates at two independent frequencies, modulating (fsm andalternating (fsc frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.

Meghana G Naik,

2014-11-01

73

Design and Implementation of Anti-windup PI Control on DC-DC Bidirectional Converter for Hybrid Vehicle Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Well-regulated DC bus voltage is the important point to guarantee power demand fulfillment in hybrid vehicle applications. Voltage regulation can be achieved with control method that determines switching signal on DC-DC converter. This paper describes the design and small scale experiment results of bus voltage regulation control for  DC-DC bidirectional converter with battery and supercapacitor as energy sources. The control system consisted of two control loops. The outer loop got DC bu...

Muh. Zakiyullah Romdlony; Amin Amin

2012-01-01

74

Interleaved Self-Oscillating Class E Derived Resonant DC/DC Converters  

DEFF Research Database (Denmark)

A new method for achieving self-oscillating, self-interleaved operation of class E derived resonant DC/DC converters is presented. The proposed method is suitable for operation at frequencies in the Very High Frequency (VHF) band. Interleaved and self-oscillating modes of operation are achieved at the same time with very small number of additional passive components in the interconnection network. To verify the proposed technique, a 110MHz prototype resonant boost converter was designed; experimental results and comparison with SPICE simulation are presented. Peak measured efficiency was 89% in continuous operation.

Kovacevic, Milovan; Knott, Arnold

2012-01-01

75

Two-Phase Interleaved Buck Converter with a new Digital Self-Oscillating Modulkator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new Digital Self-Oscillating Modulator (DiSOM) for DC/DC converters. The DiSOM modulator alllows the digital control algorithm to sample the output voltage at a sampling frequency higher than the converter switching frequency. This enables higher control loop bandwidth than for traditional digital PWM modulators given a certain switching frequency. A synchronised version of the DiSOM modulator is derived for interleaved converters. A prototype interleaved Buck convert...

Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.

2007-01-01

76

Li-Ion Battery Charging with a Buck-Boost Power Converter for a Solar Powered Battery Management System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper analyzes and simulates the Li-ion battery charging process for a solar powered battery management system. The battery is charged using a non-inverting synchronous buck-boost DC/DC power converter. The system operates in buck, buck-boost, or boost mode, according to the supply voltage conditions from the solar panels. Rapid changes in atmospheric conditions or sunlight incident angle cause supply voltage variations. This study develops an electrochemical-based equivalent circuit mod...

Chien-Wei Ma; Jaw-Kuen Shiau

2013-01-01

77

Comparison of control schemes for a fuel cell hybrid tramway integrating two dc/dc converters  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a comparative study of two control schemes for the energy management system of a hybrid tramway powered by a Polymer Electrolyte Membrane (PEM) Fuel Cell (FC) and an Ni-MH battery. The hybrid system was designed for a real surface tramway of 400 kW. It is composed of a PEM FC system with a unidirectional dc/dc boost converter (FC converter) and a rechargeable Ni-MH battery with a bidirectional dc/dc converter (battery converter), both of which are coupled to a traction dc bus. The PEM FC and Ni-MH battery models were designed from commercially available components. The function of the two control architectures was to effectively distribute the power of the electrical sources. One of these control architectures was a state machine control strategy, based on eight states. The other was a cascade control strategy which was used to validate the results obtained. The simulation results for the real driving cycle of the tramway reflected the optimal performance of the control systems compared in this study. (author)

Fernandez, L.M.; Garcia, P.; Garcia, C.A. [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n, 11202 Algeciras (Cadiz) (Spain); Torreglosa, J.P.; Jurado, F. [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, n 28. 23700 Linares (Jaen) (Spain)

2010-06-15

78

Comparison of MPPT Algorithms for DC-DC Converters Based PV Systems  

Directory of Open Access Journals (Sweden)

Full Text Available The comparative study between two most popular algorithms technique which is incremental conductance algorithm and perturbs and observe algorithm. Two different converters buck and boost converter use for comparative in this study. Few comparison such as voltage, current and power output for each different combination has been recorded.MATLAB Simulink tools have been used for performance evaluation on energy point.

A.PRADEEP KUMAR YADAV

2013-01-01

79

Averaging Method for PWM DC-DC Converters Operating in Discontinuous Conduction Mode with Feedback  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a one-cycle-average (OCA discrete-time model for PWM dc-dc converter basedonclosed-loop control method for discontinuous conduction mode (DCM is presented. It leadstoexact discrete-time mathematical representation of the OCA values of the output signal evenatlow frequency. It also provides the exact discrete-time mathematical representation oftheaverage values of other internal signals with little increase in simulation time. A comparison ofthismodel to other existing models is presented through a numerical example of boostconverter.Detailed simulation results confirm the better accuracy and speed of the proposedmodel.

N.M. ADAMALI SHAH, Mohammed S. Al-Numay

2011-08-01

80

Analysis and design of PPFHB bidirectional DC-DC converter with coupled inductors  

DEFF Research Database (Denmark)

In this paper, a novel push-pull-forward half-bridge (PPFHB) bi-directional DC-DC converter with coupled inductors is proposed. All switches can operate under zero-voltage-switching (ZVS). The operation principle with phase-shift modulation scheme, characteristics of coupled inductors, the steady state relationship and small-signal model are analyzed. The voltage controller based on the small-signal model in z-domain is designed. A 500W prototype controlled by TMS320F2808 DSP is implemented and tested. Experimental results show the validity of the analysis and design.

Zhang, Zhe; Thomsen, Ole Cornelius

2009-01-01

 
 
 
 
81

Comparison of two different high performance mixed signal controllers for DC/DC converters  

DEFF Research Database (Denmark)

This paper describes how mixed signal controllers combining a cheap microcontroller with a simple analogue circuit can offer high performance digital control for DC/DC converters. Mixed signal controllers have the same versatility and performance as DSP based controllers. It is important to have an engineer experienced in microcontroller programming write the software algorithms to achieve optimal performance. Two mixed signal controller designs based on the same 8-bit microcontroller are compared both theoretically and experimentally. A 16-bit PID compensator with a sampling frequency of 200 kHz implemented in the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated.

Jakobsen, Lars TØnnes; Andersen, Michael Andreas E.

2006-01-01

82

A VHF Class E DC-DC Converter with Self-Oscillating Gate Driver  

DEFF Research Database (Denmark)

This paper describes the analysis and design of a DC-DC converter topology which is operational at frequencies in the Very High Frequency (VHF) band ranging from 30 MHz ? 300 MHz. The presented topology, which consists of a class E inverter, class E rectifier, and self-oscillating gate driver, is inherently resonant, and switching losses are greatly reduced by ensuring Zero Voltage Switching (ZVS) of the power semiconductor devices. A design method to ensure ZVS operation when combining the inverter, rectifier, and gate driver is provided. Several parasitic effects and their influence on converter operation are discussed, and measurement results of a 100 MHz prototype converter are presented and evaluated. The designed prototype converter verifies the described topology.

Andersen, Toke Meyer; Christensen, SØren K.

2011-01-01

83

A Two-stage DC-DC Converter for the Fuel Cell-Supercapacitor Hybrid System  

DEFF Research Database (Denmark)

A wide input range multi-stage converter is proposed with the fuel cells and supercapacitors as a hybrid system. The front-end two-phase boost converter is used to optimize the output power and to reduce the current ripple of fuel cells. The supercapacitor power module is connected by push-pull-forward half bridge (PPFHB) converter with coupled inductors in the second stage to handle the slow transient response of the fuel cells and realize the bidirectional power flow control. Moreover, this cascaded structure simplifies the power management. The control strategy for the whole system is analyzed and designed. A 1kW prototype controlled by TMS320F2808 DSP is built in the lab. Simulation and experimental results confirm the feasibility of the proposed two stage dc-dc converter system.

Zhang, Zhe; Thomsen, Ole Cornelius

2009-01-01

84

A DC-DC Converter with Wide Input Voltage Range for Fuel Cell and Supercapacitor Application  

DEFF Research Database (Denmark)

This paper proposes a novel phase-shift plus duty cycle controlled hybrid bi-directional DC-DC converter based on fuel cells and supercapacitors. The described converter employs two high frequency transformers to couple the half-bridge and full-bridge circuits together in the primary side and voltage doubler circuit in secondary side. Boost type converter can limit the output ripple current of the fuel cells; hybrid full-bridge structure can change operating modes according to the different input voltage; phase-shift with duty cycle control scheme is utilized to control the bidirectional power flow flexibly. All the switches can turn on under zero-voltage-switching condition (ZVS). The operating principles of the converter are described in details, and the experimental results based on the prototype controlled by DSP are presented to verify the validity of the analysis and design.

Zhang, Zhe; Thomsen, Ole Cornelius

2009-01-01

85

Four Quadrants Integrated Transformers for Dual-input Isolated DC-DC Converters  

DEFF Research Database (Denmark)

A common limitation of power coupling effect in some known multiple-input dc-dc converters has been addressed in many literatures. In order to overcome this limitation, a new concept for decoupling the primary windings in the integrated multiple-winding transformers based on 3-dimensional (3D) space orthogonal flux is proposed in this letter. And thus a new geometry core and relative winding arrangements are proposed in accordance with the orthogonal flux decoupling technology. Due to the four secondary windings are arranged in a quadratic pattern at the base core plate with the two perpendicular primary windings, a name of “four quadrants integrated transformers” (FQIT) is therefore given to the proposed construction. Since the two primary windings are uncoupled, the FQIT allows the two input power stages to transfer the energy into the output load simultaneously or at any timemultiplexing scheme, which can optimize the utilization of input sources, simplify the system structure and reduce the overall cost, so they are attractive for the hybrid renewable power system. Section IV initiates a discussion for the advantages of the FQIT. In order to verify the feasibility of the FQIT in multiple-input converter, a dualinput isolated boost dc-dc converter with the FQIT is designed and tested. The results have excellently demonstrated that the two input power stages can be operated independently and the correctness of all the analysis in the letter.

Ouyang, Ziwei; Zhang, Zhe

2012-01-01

86

A new DC-DC converter technology suitable to support grid connection of wave power energy converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Since 2002, the department of electricity at Uppsala university has pushed the Lysekil project. The project has a number of wave energy converters installed in the sea southwest of Lysekil. The purpose of this work is to design, build and test a DC-DC converter, which will later be used as a necessary part of the grid connection of a wave energy converter. Since a wave energy converter does not generate electricity at a constant frequency, it is not possible to use a gearbox. Instead, power i...

Back, Erik

2012-01-01

87

Isolated Bidirectional Full-Bridge DC–DC Converter with a Flyback Snubber  

Directory of Open Access Journals (Sweden)

Full Text Available An isolated bidirectional full-bridge dc–dc converter with high conversion ratio, high output power, and soft start-up capability is proposed in this paper. The use of a capacitor, a diode, and a flyback converter can clamp the voltage spike caused by the current difference between the current-fed inductor and leakage inductance of the isolation transformer, and can reduce the current flowing through the active switches at the current-fed side. Operational principle of the proposed converter is first described, and then, the design equation is derived. A 1.5-kW prototype with low-side voltage of 48 V and high-side voltage of 360 V has been implemented, from which experimental results have verified its feasibility.

Chitanya

2013-05-01

88

A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application  

DEFF Research Database (Denmark)

This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase-shift modulation scheme, all the switches can realize zero-voltageswitching (ZVS) turn-on and bidirectional power flow can be controlled with phase-shift angle. The operating principles of the converter are described in detail, ZVS conditions are discussed, parameters are designed, and the experimental results based on the prototype controlled by DSP are presented to verify the validity of the analysis and design.

Zhang, Zhe; Thomsen, Ole Cornelius

2009-01-01

89

A High Voltage-lift Efficient Isolated Full Bridge DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of this study is to propose a high voltage lift isolated full bridge dc-dc converter. The proposed converter consists of an isolation transformer a low turn ratio to obtain high step up voltage gain. The secondary of the transformer connected with two boosting capacitors which connects parallel when power switches switch on period and discharged in series during the switch off period. In addition full bridge converter on primary side consists of clamping diode and capacitor, leakage energy is recycled there by improving conversion efficiency. The proposed circuits simulated using PSIM software form input voltage of 48V, an output of 410 V obtained. These results and operations experimented and validated by implementing in hardware model at 20/40 Vdc, 20 Watts.

A. Gopi

2014-05-01

90

Time delay control for fuel cells with bidirectional DC/DC converter and battery  

Energy Technology Data Exchange (ETDEWEB)

Transient behavior is a key property in the vehicular application of proton exchange membrane (PEM) fuel cells. A better control technology is constructed to increase the transient performance of PEM fuel cells. A steady-state isothermal analytical fuel cell model is constructed to analyze mass transfer and water transport in the membrane. To prevent the starvation of air in the PEM fuel cell, time delay control is used to regulate the optimum stoichiometric amount of oxygen, although dynamic fluctuations exist in the PEM fuel cell power. A bidirectional DC/DC converter connects the battery to the DC link to manage the power distribution between the fuel cell and the battery. Dynamic evolution control (DEC) allows for adequate pulse-width modulation (PWM) control of the bidirectional DC/DC converter with fast response. Matlab/Simulink/Simpower simulation is performed to validate the proposed methodology, increase the transient performance of the PEM fuel cell system and satisfy the requirement of energy management. (author)

Kim, Y.B. [Mechanical Engineering Department, Chonnam National University, Gwangju (Korea); Kang, S.J. [Mechatronics Engineering Department, Korea Polytechnic College V, Gwangju (Korea)

2010-08-15

91

Analyzing switched circuits to design DC-DC and DC-AC converters  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: English Abstract in spanish El propósito de este artículo es presentar un análisis alternativo de circuitos conmutados para diseñar generadores de onda cuadrada, SWG (del Inglés Square Wave Generator). Un SWG puede ser diseñado usando componentes electrónicos de bajo costo, lo cual permite al lector comprender como los convert [...] idores DC-DC y DC-AC basados en la aproximación conmutada es una opción económica para introducir conceptos del análisis de redes. Los resultados experimentales muestran que las técnicas usadas permiten calcular el rango de operación no solo de los componentes electrónicos sino también del efecto que el valor de la fuente de alimentación tiene en el desempeño de los generadores. Abstract in english The purpose of this paper is to present an alternative analysis of switched circuit to design square wave generators (SWG). A SWG may be designed by using low-cost electronic components, which allows to the readers to understand how DC-DC and DC-AC converters based on the switched approach is an eco [...] nomic option to introduce network analysis concepts. Experimental results show that used techniques allow calculate the frequency range operation not only of the electronic components but also the effect of the power supply value on the generators' performance.

F., Sandoval-Ibarra; J., Mercado-Moreno; A., Lopez; R., Martínez-Rivera; T., Alba-García.

2007-06-01

92

Designing and Parametric Variation of PI Controller for Buck Converter for Constant Voltage Applications  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we study on buck dc/dc converter of high efficiency by soft switching technique. The paper will focus on modeling, analysis, and design and simulation buck converter architecture. The converter is designed in CCM (continuous conduction mode. The voltage mode control strategy is proposed by using pulse width modulation (PWM with a proportional-integral (PI. The effectiveness of the step down converter is verified through simulation results using control oriented simulator like MATLAB/Simulink tools. The circuit operation, designs and simulation results are mentioned in this paper.

Sugandhra Pal Singh

2014-07-01

93

Dielectric Electro Active Polymer Incremental Actuator Driven by Multiple High-Voltage Bi-directional DC-DC Converters  

DEFF Research Database (Denmark)

This paper presents driving circuit for a recently invented dielectric electro active polymer (DEAP) incremental actuator. The basic operation of such an actuator is bioinspired from the movement of an inchworm. The actuator consists of three electrically isolated, and mechanically connected capacitive sub-actuators. It needs to be driven by three high voltage (~2.5 kV) DC-DC converters, to achieve the linear incremental motion. The topology used for this application is a bi-directional flyback DC-DC converter. The control of the incremental actuator involves, implementation of digital controller used for controlling charge and discharge sequences of the individual sub-actuators, and monitoring and adjustment of the output voltages of three high voltage DC-DC converters to provide over-voltage protection capability. Three power stages of the proposed converter were experimentally tested. The experimental results and efficiency measurements are shown.

Thummala, Prasanth; Zhang, Zhe

2013-01-01

94

High Step-Up DC-DC Converter for Distributed Generation System  

Directory of Open Access Journals (Sweden)

Full Text Available This study proposes a method which consists of High step up DC-DC converter with a coupled inductor for distributed generation system. Theoretically the conventional boost converter provides high step up voltage gain but in practical it is limited by reverse recovery problem of diode, effective series impedance of inductors and capacitors and switching losses. High charged current and conduction losses occur in the switch when voltage lift and switched capacitor techniques are used. In the proposed strategy a coupled-inductor and two capacitors is utilized to achieve high step-up voltage gain. High power loss and voltage spike on the switch is avoided using passive clamp circuit that recycles the leakage inductor energy. The operating principle and steady-state analysis are discussed. The Proposed topology was simulated using PSPICE SOFTWARE and the following results were obtained. For an input voltage of 24V, an output of 333V was obtained.

V.K. Jayakrishnan

2013-08-01

95

Multistability and Torus Reconstruction in a DC–DC Converter With Multilevel Control  

DEFF Research Database (Denmark)

By virtue of their limited size and relatively low costs, multilevel dc-dc converters have come to play an important role in modern industrial power supply systems. When operating in a regime of high corrector gain, such converters can display a variety of new dynamic phenomena associated with the appearance of additional oscillatory modes. Starting in a state where four pairs of stable and unstable period-6 cycles coexist with the basic period-1 cycle, the paper describes a sequence of smooth and nonsmooth bifurcations through which the cycles and their basins of attraction transform as the output voltage is increased. The paper also describes the birth of a multilayered resonance torus through a transverse pitchfork bifurcation of the saddle cycle on an ordinary resonance torus.

Zhusubaliyev, Zhanybai T.; Mosekilde, Erik

2013-01-01

96

New ZVZCS PWM DC-DC Converters with One Auxiliary Switch  

Energy Technology Data Exchange (ETDEWEB)

This paper presents new Zero-Voltage-/Zero-Current-Switching (ZVZCS) PWM DC-DC converters. The proposed soft-switching technique achieves ZVS and ZCS simultaneously at both turn-on and turn-off of the main switch and diode by using only one auxiliary switch. Also, the proposed soft-switching technique is suitable for not only minority but also majority carrier semiconductor devices. The auxiliary circuit of the proposed topology is placed out the main power path and therefore, there are no voltage/current stresses on the main switch and diode. The operating principle of the proposed topology is illustrated by a detailed study with a boost converter as an example. Theoretical analysis, simulation and experimental results are presented to explain the proposed schemes. (author). 10 refs., 9 figs., 1 tab.

Ryu, Seung Hee [LG Electronics Ins (Korea); Lee, Dong Yun; Hyun, Dong Seok [Hanyang University (Korea); Yoo, Sang Bong [Song Dam University (Korea)

2000-03-01

97

Analyzing switched circuits to design DC-DC and DC-AC converters  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this paper is to present an alternative analysis of switched circuit to design square wave generators (SWG. A SWG may be designed by using low-cost electronic components, which allows to the readers to understand how DC-DC and DC-AC converters based on the switched approach is an economic option to introduce network analysis concepts. Experimental results show that used techniques allow calculate the frequency range operation not only of the electronic components but also the effect of the power supply value on the generators' performance.El propósito de este artículo es presentar un análisis alternativo de circuitos conmutados para diseñar generadores de onda cuadrada, SWG (del Inglés Square Wave Generator. Un SWG puede ser diseñado usando componentes electrónicos de bajo costo, lo cual permite al lector comprender como los convertidores DC-DC y DC-AC basados en la aproximación conmutada es una opción económica para introducir conceptos del análisis de redes. Los resultados experimentales muestran que las técnicas usadas permiten calcular el rango de operación no solo de los componentes electrónicos sino también del efecto que el valor de la fuente de alimentación tiene en el desempeño de los generadores.

F. Sandoval-Ibarra

2007-06-01

98

Maximum Power Point Tracking Controller for Thermoelectric Generators with Peak Gain Control of Boost DC-DC Converters  

Science.gov (United States)

An analog maximum power point tracking (MPPT) circuit for a thermoelectric generator (TEG) is proposed. We show that the peak point of the voltage conversion gain of a boost DC-DC converter with an input voltage source having an internal resistor is the maximum power point of the TEG. The key characteristic of the proposed MPPT controller is that the duty ratio of the input clock pulse to the boost DC-DC converter shifts toward the maximum power point of the TEG by seeking the peak gain point of the boost DC-DC converters. The proposed MPPT technique provides a simple and useful analog MPPT solution, without employing digital microcontroller units.

Park, Jungyong; Kim, Shiho

2012-06-01

99

Closed loop control of ZVS half bridge DC-DC converter with DCS PWM Control  

Directory of Open Access Journals (Sweden)

Full Text Available

The main drawback of the conventional symmetric control is that both primary switches in the converter operate at hard switching condition. Moreover, during the off-time period of two switches, the oscillation between the transformer leakage inductance and junction capacitance of the switches results in energy dissipation and electromagnetic interference (EMI emissions due to reverse recovery of MOSFETs body diodes. The asymmetric (complementary control was proposed to achieve ZVS operation for HB switches. However, asymmetric stresses distribution on the corresponding components may occur due to the asymmetric duty cycle distribution for the two primary switches. A new control scheme, to be known as duty-cycle shifted PWM (DCS PWM control, is proposed and applied to the conventional HB dc–dc converters to achieve ZVS for both the  switches without adding extra components and without adding asymmetric penalties of the complementary control. The concept of this new control scheme is shifting one of the two symmetric PWM driving signals close to the other, such that ZVS may be achieved for the lagging switch due to the shortened resonant interval. Moreover, based on the DCS PWM control, a new half-bridge topology is proposed to achieve ZVS for both the main switches and auxiliary switch by adding an auxiliary switch and diode in the proposed half bridge. ZVS for the  switch is achieved by utilizing the energy trapped in the leakage inductance. There are two control schemes. One is open loop and the other is closed loop. In open loop scheme, the given dc-dc converter is operating under disturbance. This disturbance effect is eliminated in closed loop scheme.

 

JANAPATI SIVAVARA PRASAD

2012-10-01

100

Quasiperiodicity and Torus Breakdown in a Power Electronic DC/DC Converter  

DEFF Research Database (Denmark)

This paper discusses the mechanisms of torus formation and torus destruction in a dc/dc converter with relay control and hysteresis. We establish a chart of the dynamical modes in the input voltage versus load resistance parameter plane. This chart displays several different torus bifurcations along with their associated resonance tongues where periodic dynamics is observed. We show how a quintruple-turn torus is transformed into a single-turn torus in a homoclinic bifurcation and examine different mechanisms of torus destruction (via horseshoe formation and through period doubling). Particular emphasis is paid to following the changes of the stable and unstable manifolds in detail. (c) 2006 Published by Elsevier B.V. on behalf of IMACS.

Zhusubaliyev, Zhanybai; Soukhoterin, Evgeniy

2007-01-01

 
 
 
 
101

Multistability and hidden attractors in a multilevel DC/DC converter  

DEFF Research Database (Denmark)

An attracting periodic, quasiperiodic or chaotic set of a smooth, autonomous system may be referred to as a "hidden attractor" if its basin of attraction does not overlap with the neighborhood of an unstable equilibrium point. Historically, this condition has implied that the basin of attraction for the hidden set in most cases has been so complicated that special analytic and/or numerical techniques have been required to locate the set. By simulating the model of a multilevel DC/DC converter that operates in the regime of high feedback gain, the paper illustrates how pulse-width modulated control can produce complicated structures of attracting and repelling states organized around the basic switching cycle. This leads us to suggest the existence of hidden attractors in such systems as well. In this case, the condition will be that the basin of attraction does not overlap with the fixed point that represents the basic switching cycle.

Zhusubaliyev, Zhanybai T.; Mosekilde, Erik

2015-01-01

102

A High Efficiency DC-DC Converter Topology Suitable for Distributed Large Commercial and Utility Scale PV Systems  

Energy Technology Data Exchange (ETDEWEB)

In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements

Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Steigerwald, Robert L; Sabate, Juan A; Chi, Song; McCann, Adam J; Zhang, Li; Mueller, Frank

2012-09-01

103

Planar Integrated Magnetics (PIM) Module in Hybrid Bidirectional DC-DC Converter for Fuel Cell Application  

DEFF Research Database (Denmark)

In most power electronics converters, the overall volume is mainly determined by the number of parts and the size of passive components. Integrated magnetics and planar magnetics techniques therefore have been an excellent option in order to reduce the counts and the size of magnetic components, hereby increasing the power density of converters. In this paper, a new planar integrated magnetics (PIM) module for a phase-shift plus duty cycle controlled hybrid bi-directional dc-dc converter is proposed, which assembles one boost inductor and two transformers into an E-I-E core geometry, reducing the number of parts, the total volume of converter, as well as the total core loss of the magnetic components. AC losses in the windings and leakage inductance of the transformers are kept low by interleaving the primary and secondary turns of the transformers. To verify the validity of the design approach and theoretical analysis, a lab prototype employing the PIM module is implemented for a fuel cell application with 20~40 V input voltage and 400 V output voltage. Detailed results from the experimental comparisons demonstrate that the PIM module is fully functional and electromagnetically equivalent to the discrete magnetics and a significant reduction of size can be achieved by using the PIM module.

Ouyang, Ziwei; Zhang, Zhe

2011-01-01

104

Design Of Vswt With Lcl Resonant Dc-dc Converters For Rl Load  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper deals with design of variable speed wind turbine (VSWT) with LCL resonantDC-to-DC converter for stand-alone wind energy system with RL load. The wind turbinesystem consists of synchronous generator (SG), full bridge diode rectifier, buck DC- DCconverter and inverter with RL load is present. Based on this electrical model, a Simulinkmodel of the system are simulated by using MATLAB Simulink power system blocks. Thisconverter has advantages like reduced transformer size, reduced filt...

Vijaya Kumar, M.; Annamalai, M.

2012-01-01

105

Dynamic modeling of DC-DC converters with peak current control in double-stage photovoltaic grid-connected inverters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In photovoltaic (PV) double-stage grid-connected inverters a high-frequency DC-DC isolation and voltage step-up stage is commonly used between the panel and the grid-connected inverter. This paper is focused on the modeling and control design of DC-DC converters with Peak Current mode Control (PCC) and an external control loop of the PV panel voltage, which works following a voltage reference provided by a maximum power point tracking (MPPT) algorithm. In the proposed overall control structur...

Garcera? Sanfeliu?, Gabriel; Gonza?lez Medina, Raul; Figueres Amoro?s, Emilio; Sandia Paredes, Jesu?s

2012-01-01

106

Influence of the snubbers and matching transformer on an optimal trajectory controlled resonant transistor DC/DC converter  

Directory of Open Access Journals (Sweden)

Full Text Available This work examines a series resonant DC/DC optimal trajectory controlled converter during operation above resonant frequency, taking into account the influence of the snubbers and matching transformer. We obtain expressions for the load characteristics, boundary curves between possible modes and limits of the soft commutation area. Computer simulation and experimental observation confirm the theoretical results.

Bankov Dimitrov Nikolay

2012-01-01

107

Design and Implementation of Battery Charger with Power Factor Correction using Sepic Converter and Full-bridge DC-DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a design and implementation of a converter which has a high power factor for battery charger application. The converter is a combination of a SEPIC converter and a full-bridge dc-dc converter connected in two stages of series circuit. The SEPIC converter works in discontinuous conduction mode and it serves as a power factor corrector so that the shape of input current waveform follows the shape of input voltage waveform. The full-bridge dc-dc converter serves as a regulato...

Efendi Moh. Zaenal; Windarko Novie Ayub; Amir Faisal Moh.

2013-01-01

108

Multi-output DC-DC converters based on diode-clamped converters configuration : topology and control strategy  

DEFF Research Database (Denmark)

This study presents a new DC DC multi-output boost (MOB) converter which can share its total output between different series of output voltages for low- and high-power applications. This configuration can be utilised instead of several single output power supplies. This is a compatible topology for a diode-clamed inverter in the grid connection systems, where boosting low rectified output-voltage and series DC link capacitors is required. To verify the proposed topology, steady-state and dynamic analyses of a MOB converter are examined. A simple control strategy has been proposed to demonstrate the performance of the proposed topology for a double-output boost converter. The topology and its control strategy can easily be extended to offer multiple outputs. Simulation and experimental results are presented to show the validity of the control strategy for the proposed converter.

Nami, A.; Zare, F.

2010-01-01

109

Analysis of Dc/Dc converters with PWM and sliding mode controls  

International Nuclear Information System (INIS)

Static and dynamic performances of D C/D C converters with PWM and sliding mode controllers are investigated. To improve the performance of the PWM controller, a linear compensator is proposed and used. For sliding controller, important parameters such as sliding coefficients and filter time constant are carefully computed and used. Finally, a D C/D C buck converter with PWM and sliding controller is designed, modeled and constructed. Theoretical and experimental results are compared and the distinguished features and limitations of each control technique are presented

110

Designing Controller for Joined Dynamic Nonlinear PEMFC and Buck Converter System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Designing controller for a class of dynamical nonlinear model for Polymer Electrolyte Membrane Fuel Cell (PEMFC) is discussed in this paper inwhich the PEMFC system is used for powering a Notebook PC (Processing Computer). The power requirement of a Notebook PC varies significantly under different operational conditions. The proposed feedback controller is applied for the buck dc/dc converter to stabilize the load voltage at a desirable level under various operational conditions. The simulati...

Rahimi Khoygani, M. R.; Ghasemi, R.; Sanaei, D.

2014-01-01

111

High-Temperature SOI/SiC-Based DC-DC Converter Suite  

Directory of Open Access Journals (Sweden)

Full Text Available A complete design strategy (mechanical and electrical for a 25 W 28 V/5 V dc-dc converter utilizing SiC and SOI electronics is presented. The converter includes a high-temperature SOI-based PWM controller featuring 150 kHz operation, a PID feedback loop, maximum duty cycle limit, complementary or symmetrical outputs, and a bootstrapped high-side gate driver. Several passive technologies were investigated for both control and power sections. Capacitor technologies were characterized over temperature and over time at 300C∘, power inductors designed and tested up to 350C∘, and power transformers designed and tested up to 500C∘. Northrop Grumman normally-off SiC JFETs were used as power switches and were characterized up to 250C∘. Efficiency and mass optimization routines were developed with the data gained from the first prototype. The effects of radiation on SiC and SOI electronics are then discussed. The results of the first prototype module are presented, with operation from 25C∘ up to an ambient temperature of 240C∘ .

Brice McPherson

2008-08-01

112

Progress on DC-DC Converters for a Silicon Tracker for the sLHC Upgrade  

CERN Document Server

There is a need for DC-DC converters which can operate in the extremely harsh environment of the sLHC Si Tracker. The environment requires radiation qualification to a total ionizing radiation dose of 50 Mrad and a displacement damage fluence of 5 x 1014 /cm2 of 1 MeV equivalent neutrons. In addition a static magnetic field of 2 Tesla or greater prevents the use of any magnetic components or materials. In February 2007 an Enpirion EN5360 was qualified for the sLHC radiation dosage but the converter has an input voltage limited to a maximum of 5.5V. From a systems point of view this input voltage was not sufficient for the application. Commercial LDMOS FETs have developed using a 0.25 ?m process which provided a 12 volt input and were still radiation hard. These results are reported here and in previous papers. Plug in power cards with ×10 voltage ratio are being developed for testing the hybrids with ABCN chips. These plug-in cards have air coils but use commercial chips that are not designed to be radiatio...

Dhawan, S; Chen, H; Khanna, R; Kierstead, J; Lanni, F; Lynn, D; Musso, C; Rescia, S; Smith, H; Tipton, P; M. Weber, M

2009-01-01

113

Optimal Design and Tradeoff Analysis of Planar Transformer in High-Power DC–DC Converters  

DEFF Research Database (Denmark)

The trend toward high power density, high operating frequency, and low profile in power converters has exposed a number of limitations in the use of conventional wire-wound magnetic component structures. A planar magnetic is a low-profile transformer or inductor utilizing planar windings, instead of the traditional windings made of Cu wires. In this paper, the most important factors for planar transformer (PT) design including winding loss, core loss, leakage inductance, and stray capacitance have individually been investigated. The tradeoffs among these factors have to be analyzed in order to achieve optimal parameters. Combined with an application, four typical winding arrangements have been compared to illustrate their advantages and disadvantages. An improved interleaving structure with optimal behaviors is proposed, which constructs the top layer paralleling with the bottom layer and then in series with the other turns of the primary, so that a lower magnetomotive force ratio $m$ can be obtained, as wellas minimized ac resistance, leakage inductance, and even stray capacitance. A 1.2-kW full-bridge dc–dc converter prototype employing the improved PT structure has been constructed, over 96% efficiency is achieved, and a 2.7% improvement, compared with the noninterleaving structure, is obtained.

Ouyang, Ziwei; Thomsen, Ole Cornelius

2012-01-01

114

High Output Voltage Based Multiphase Step-Up DC-DC Converter Topology with Voltage Doubler Rectifiers  

Directory of Open Access Journals (Sweden)

Full Text Available High Output Voltage Based Multiphase Step-Up DC-DC Converter topology with voltage doubler rectifiers is presented in this paper. High output voltage is obtained due to the series combination of voltage doubler rectifiers on the secondary side of high frequency transformers. This topology is useful in the application where the output voltage is greater than the input. The two loop control strategy has been developed in order to analyze the stable and effective working of the converter topology. Therefore the working mode analysis of the converter topology has been described in detail. The multiphase step-up DC-DC converter topology is first simulated on MATLAB and then a prototype has been designed in order to verify the simulation and experimental results. Finally the simulation and experimental results are found to be satisfactory.

Liao Xiaozhong

2013-02-01

115

Investigation of DC-DC Converter Modeling from the Perspective of Control and Input-Filter Influence  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Modeling and control of switched-mode dc-dc converters has occupied a center stage in the field of modern power electronics due to their widespread military and industrial applications. Averaged modeling is most commonly applied as an effective tool to analyze dynamic behavior of a converter and to get physical insights into various dynamical phenomena. State-space averaged models are widely accepted in practice mainly because of their simplicity, generality and demonstrated practical utility...

Usman Iftikhar, Muhammad

2008-01-01

116

High Output Voltage Based Multiphase Step-Up DC-DC Converter Topology with Voltage Doubler Rectifiers  

Digital Repository Infrastructure Vision for European Research (DRIVER)

High Output Voltage Based Multiphase Step-Up DC-DC Converter topology with voltage doubler rectifiers is presented in this paper. High output voltage is obtained due to the series combination of voltage doubler rectifiers on the secondary side of high frequency transformers. This topology is useful in the application where the output voltage is greater than the input. The two loop control strategy has been developed in order to analyze the stable and effective working of the converter topolog...

Liao Xiaozhong; Shahnawaz Farhan Khahro; Xu Lingyu; Amir Mahmood Soomro

2013-01-01

117

Development of a Novel Bi-Directional Isolated Multiple-Input DC-DC Converter  

Energy Technology Data Exchange (ETDEWEB)

There is vital need for a compact, lightweight, and efficient energy-storage system that is both affordable and has an acceptable cycle life for the large-scale production of electric vehicles (EVs) and hybrid electric vehicles (HEVs). Most of the current research employs a battery-storage unit (BU) combined with a fuel cell (FC) stack in order to achieve the operating voltage-current point of maximum efficiency for the FC system. A system block diagram is shown in Fig.1.1. In such a conventional arrangement, the battery is sized to deliver the difference between the energy required by the traction drive and the energy supplied by the FC system. Energy requirements can increase depending on the drive cycle over which the vehicle is expected to operate. Peak-power transients result in an increase of losses and elevated temperatures which result in a decrease in the lifetime of the battery. This research will propose a novel two-input direct current (dc) dc to dc converter to interface an additional energy-storage element, an ultracapacitor (UC), which is shown in Fig.1.2. It will assist the battery during transients to reduce the peak-power requirements of the battery.

Li, H.

2005-10-24

118

Optimal Design and Tradeoffs Analysis for Planar Transformer in High Power DC-DC Converters  

DEFF Research Database (Denmark)

A planar magnetic is a low profile transformer or inductor utilizing planar windings instead of the traditional windings made of Cu-wires. In this paper, the important factors for planar transformer design including winding loss, core loss, leakage inductance and stray capacitance have been investigated individually. The tradeoffs among these factors have to be analyzed in order to achieve optimal parameters. Combined with a certain application, four typical winding arrangements have been compared to illustrate each their advantages and disadvantages. An improved interleaving structure with optimal behaviors is proposed, which constructs the top layer paralleling with the bottom layer and then in series with the other turns of the primary so that a lower magneto motive force (MMF) ratio m can be obtained as well as minimized AC resistance, leakage inductance and even stray capacitance. A 1.2-kW full-bridge DC-DC converter prototype employing the improved planar transformer structure has been constructed, over96% efficiency is achieved and a 2.7% improvement compared to the non-interleaving structure is obtained.

Ouyang, Ziwei; Thomsen, Ole Cornelius

2010-01-01

119

Implementation of Buck-Boost Converter with Coupled Inductor for Photo-Voltaic System  

Directory of Open Access Journals (Sweden)

Full Text Available The solar energy is a very interesting alternative on supplement the electrical system generation. In this paper, a photovoltaic based system is obtained from a boost cascaded with a buck converter along with Coupled inductor. Due to its novel operating modes, high efficiency can be achieved because there is only one switch operating at high frequency at a time, and the converter allows the use of power MOSFET and ultra-fast reverse recovery diode. This paper begins with theoretical analysis and modeling of this boost–buck converter. The model indicates that the coupled inductance will lead to an increase in the gain and the decrease in ripples. Finally, this paper analyzes and describes step by step the process of designing, and simulation of high efficiency low ripple voltage buck boost DC-DC converter for the photovoltaic solar conversion system

M.S. Subbulakshmi

2014-12-01

120

Non-Inverting Buck-Boost Converter for Fuel Cell Applications  

DEFF Research Database (Denmark)

Fuel cell DC/DC converters often have to be able to both step-up and step-down the input voltage, and provide a high efficiency in the whole range of output power. Conventional negative output buck-boost and non-inverting buck-boost converters provide both step-up and step-down characteristics. In this paper the non-inverting buck-boost with either diodes or synchronous rectifiers is investigated for fuel cell applications. Most of previous research does not consider  the parasitic in the evaluation of the converters. In this study, detailed analytical expressions of the efficiencies for the system composed of fuel cell system and interfacing converter, considering the parasitics, are presented. It is concluded that the implementation with synchronous rectifiers provides the highest efficiency in the whole range of the fuel cell power, and its efficiency characteristic is more suitable for fuel cell applications than the implementation with diodes.

Schaltz, Erik; Rasmussen, Peter Omand

2008-01-01

 
 
 
 
121

Planar integrated magnetics design in wide input range DC-DC converter for fuel cell application  

DEFF Research Database (Denmark)

In the most power electronics converters, the overall volume is mainly determined by the number of parts and the size of passive components. Integrated magnetics and planar magnetics techniques therefore have been an excellent option in order to reduce the count and the size of magnetic components, hereby increasing the power density of converters. A new planar integrated magnetics (PIM) technique for a phase-shift plus duty cycle controlled hybrid bi-directional DC/DC converter is presented and investigated in this paper. The main magnetic components including one boost inductor and two independent transformers are integrated into an E-I-E core geometry. Utilizing the flux cancellation as the principle of uncoupling, the transformers and the boost inductor are integrated, to reduce the total ferrite volume and core loss. The transformers and inductor are wound in the outer legs and the center legs respectively. The uncoupling effect between them is determined by the winding connections. The middle I-core provides a shared low reluctance flux path, uncoupling the two independent transformers. With the air gaps shift into the center legs, the magnetizing inductance of transformers will not be decreased due to there is no air gap throughout the flux paths generated by the two transformers. The new PIM structure can be extended to other topologies. To verify the validity of design approach and theoretical analysis, a lab prototype with PIM has been built, and tested. Comparing with the discrete structure, the result demonstrated a great improvement in profile and volume without sacrificing electrical performance.

Ouyang, Ziwei; Zhang, Zhe

2010-01-01

122

Design and Implementation of Anti-windup PI Control on DC-DC Bidirectional Converter for Hybrid Vehicle Applications  

Directory of Open Access Journals (Sweden)

Full Text Available Well-regulated DC bus voltage is the important point to guarantee the power demand in hybrid vehicle applications. Voltage regulation can be achieved with control method that build switching signal on DC-DC converter. This paper describes design and small scale experimental results of bus voltage regulation control of the DC-DC bidirectional converter with battery and supercapacitor as energy source. The control system consists of two control loops, the outer loop that get DC bus voltage feedback using PI anti-windup back calculation control method. This outer loop will generate a reference current for the inner loop that implement hysteresis control. The inner control loop will compare that reference curent with the source current obtained from the current sensor. Simulation and experimental results show that bus voltage is well-regulated under the load changes with 1% voltage ripple.

Muh. Zakiyullah Romdlony

2012-07-01

123

High voltage boost DC-Dc converter suitable for variable voltage sources and high power photovoltaic application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Important considerations of a photovoltaic (PV) source are achieving a high voltage and drawing currents with very little ripple component from it. Furthermore, the output from such a source is variable depending on irradiation and temperature. In this research, literature review of prior methods employed to boost the output voltage of a PV source is examined and their limitations identified. This research then proposes a multi-phase tapped-coupled inductor boost DC-DC converter that can achi...

Mwaniki, Fredrick Mukundi

2013-01-01

124

State Space Analysis and Modeling of DC-DC Converter With High Frequencies  

Directory of Open Access Journals (Sweden)

Full Text Available The design of the control law for power converter can be a complex task especially when high performance is required against load and line variations. This difficulty can further increase in the presence of input filters. Which are intentionally under damped to decrease the converter losses. In such cases, the peak current mode control facilitates the design of control law. The usual approach for the modeling of this type of control assumes constant current ripples in smoothing inductance. However, this assumption is somewhat restrictive and limits the validity of the model at high frequency. This paper presents a modeling approach which avoids this assumption, consequently leading to a better representation of the converter at high frequencies. In order to improve its performance with respect to load and line disturbances, this kind of control implicitly integrates a feed forward compensation. The application of the developed analysis is carried out on a buck converter; however, it is equally applicable to any other type of converter. Finally the results are simulated in MATLAB/Simulink environment.

A. Suresh Kumar, M. Sreenu

2012-08-01

125

SWITCH MODE PULSE WIDTH MODULATED DC-DC CONVERTER WITH MULTIPLE POWER TRANSFORMERS  

DEFF Research Database (Denmark)

A switch mode pulse width modulated DC-DC power converter comprises at least one first electronic circuit on a input side (1) and a second electronic circuit on a output side (2). The input side (1) and the output side (2) are coupled via at least two power transformers (T1, T2). Each power transformer (T1, T2) comprises a first winding (T1a, T2a) arranged in a input side converter stage (3, 4) on the input side (1) and a second winding (T1 b, T2b) arranged in a output side converter stage (5) on the output side (2), and each of the windings (T1a, T1 b, T2a, T2b) has a first end and a second end. The first electronic circuit comprises terminals (AO, A1) for connecting a source or a load, at least one energy storage inductor (L) coupled in series with at least one of the first windings (T1a, T2a) of the power transformers (T1, T2), and for each power transformer (T1, T2), an arrangement of switches being adapted to switch the current through the first winding (T1 a, T2a) between a first ON-state, a first OFF-state, a second ON-state with a polarity opposite to the first ON-state, and a second OFF-state, and/or being adapted to provide rectified current to the terminals (AO, A1) wherein the at least one energy storage inductor (L) is arranged so as to be charged, when all switches of the switching arrangements are conducting, and the current through the at least one first winding coupled in series to the energy storage inductor is in an OFF- state. The second electronic circuit comprises terminals (BO, B1) for connecting a load or a source, a single arrangement of switches being adapted to switch the current through the second windings (T1 b, T2b) of the power transformers (T1, T2) between a first ON-state, a first OFF-state, a second ON-state with a polarity opposite to the first ON-state, and a second OFF-state, and/or being adapted to provide rectified current to the terminals (BO, B1). The second windings (T1b, T2b) of the power transformers (T1, T2) are connected in series and coupled via the single arrangement of switches of the second circuit to the terminals (BO, B1) of the output side.

Nymand, Morten Technical University of Denmark,

126

Design and Implementation of Battery Charger with Power Factor Correction using Sepic Converter and Full-bridge DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a design and implementation of a converter which has a high power factor for battery charger application. The converter is a combination of a SEPIC converter and a full-bridge DC-DC converter connected in two stages of series circuit. The SEPIC converter works in discontinuous conduction mode and it serves as a power factor corrector so that the shape of input current waveform follows the shape of input voltage waveform. The full-bridge DC-DC converter serves as a regulator of output voltage and operates at continuous conduction mode. The experimental results show that the power factor of this converter system can be achieved up to 0.96.

Moh. Zaenal Efendi

2013-12-01

127

Design and Analysis of a 24 Vdc to 48 Vdc Bidirectional DC-DC Converter Specifically for a Distributed Energy Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The design of a bidirectional dc-dc power converter specifically for a distributed energy application is presented. The existing two different DC voltage battery bank of the distributed generation needs to interlink each other using a bi-directional dc-dc converter in order to minimize the unbalance of the output load currents of the three inverters connected to electric grid system. Through this connection, a current can flow from one system to another or vice versa depending on which system...

Cultura Ii, Ambrosio B.; Salameh, Ziyad M.

2012-01-01

128

DC-DC boost-flyback converter functioning as input stage for one phase low power grid-connected inverter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The paper treats about main problems of one phase DC-AC microinverters that allow single solar cell to be joined with the grid. One of the issues is to achieve high voltage gain with high efficiency in DC circuit, which is necessary for proper operation of inverter. The operating principles, results of practical implementation and investigations on boost-flyback converter, which meets mentioned demands, are presented. (high step-up DC-DC boost-flyback converter for single phase grid microinve...

Kawa Adam; Penczek Adam; Piróg Stanis?aw

2014-01-01

129

SPECTRAL ANALYSIS OF BUCK AND SEPIC CONVERTERS  

Directory of Open Access Journals (Sweden)

Full Text Available Switched mode power converters generate harmonic currents, which will be injected into the utility grid, causing distortion of the utility waveform. They also become a source for the generation of EMI, which may affect the communication systems. This work is about the design and evaluation of the two most frequently used SMPS used in step down mode of operation: the Buck converter and the Sepic converter working in step-down mode of operation. These converters were designed using optimized equations for their components ratings. Simulation results show that although the Buck output voltage is low in harmonics, it has high harmonic contents in currents circulating in its inductor and diode, and hence requires strong filtering. The Sepic converterhas lower harmonic contents than the Buck converter.

CHAKIB ALAOUI

2011-02-01

130

A Novel Dual-input Isolated Current-Fed DC-DC Converter for Renewable Energy System  

DEFF Research Database (Denmark)

In this paper, a novel isolated current-fed DC-DC converter (boost-type) with two input power sources based on multi-transformer structure, which is suitable for fuel cells and super-capacitors hybrid energy system, is proposed and designed. With particular transformer windings connection strategy, the proposed converter can draw power from two different DC sources with lower voltage and deliver it to the higher voltage DC bus or load individually and simultaneously. The detailed operation principle of the proposed converter has been analyzed in dual-input mode and single-input mode, respectively. Furthermore, the method to increase the number of input ports, the magnetic integration structure, and ground loop decoupling are discussed. Experimental results from the lab prototype converter with two DC voltage sources verify the validity of the theoretical analysis and design of the converter.

Zhang, Zhe; Thomsen, Ole Cornelius

2010-01-01

131

IMPLEMENTACIÓN DE UNA NUEVA TÉCNICA DE CONTROL DIGITAL PARA CONVERTIDORES DC-DC Y DC-AC / IMPLEMENTATION OF A NEW DIGITAL CONTROL TECHNIQUE FOR DC-DC AND DC-AC POWER CONVERTERS  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En este trabajo se presentan resultados experimentales que confirman la validez de una nueva técnica de control digital, por modulación de ancho de pulso (PWM- Digital), para convertidores de potencia DC-DC y DC-AC. El controlador PWM-Digital combina el esquema de control por promedio cero de la din [...] ámica del error (ZAD), ya reportado en la literatura, con el esquema de control por inducción al punto fijo (FPIC) aún en fase de experimentación. El diseño ha sido validado experimentalmente, usando la plataforma digital DSpace, en convertidores DC-DC y DC-AC de baja potencia. Los diagramas de bifurcaciones, calculados numéricamente en la etapa de diseño, concuerdan en un alto porcentaje con los obtenidos en la etapa experimental. Cuando el sistema opera en zona estable se obtiene buen comportamiento a la salida (regulación en el caso DC-DC y rastreo en el caso DC-AC), con bajo error y rechazo a perturbaciones. Abstract in english In this paper, we show numerical and experimental results obtained when a new PWM-digital control technique is applied to DC-DC and DC-AC converters. The controller combines ZAD (zero average dynamics) and FPIC (Fixed point inducting controller) strategies. The first one has been reported in the lit [...] erature in the last years and the second one is still in experimental phase. The design has been tested in an experimental way in low power DC-DC and DC-AC converters, using DSpace platform. Numerical and experimental bifurcation diagrams agree. When the system is working in a stable range it has very good performance, showing low error and robustness.

FREDY EDIMER, HOYOS VELASCO; FABIOLA, ANGULO GARCIA; JOHN ALEXANDER, TABORDA GIRALDO; GERARD, OLIVAR TOST.

2010-12-01

132

Hybrid electric system based on fuel cell and battery and integrating a single dc/dc converter for a tramway  

Energy Technology Data Exchange (ETDEWEB)

Research highlights: {yields} Hybrid electric power system for a real surface tramway. {yields} Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. {yields} New control strategy for the energy management of the tramway. {yields} Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.

Fernandez, Luis M., E-mail: luis.fernandez@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Pablo, E-mail: pablo.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Carlos Andres, E-mail: carlosandres.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, Francisco, E-mail: fjurado@ujaen.e [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, No. 28. 23700 Linares (Jaen) (Spain)

2011-05-15

133

DESIGN OF NON-LINEAR CONTROLLED ZCS – QR BUCK CONVERTER USING GSSA  

Directory of Open Access Journals (Sweden)

Full Text Available A Fuzzy controlled DC-DC buck converters which maintains the load for various load and line conditions is presented in this paper. Processors exhibit variation in load current dynamically from few mA to Amps during operation. In this paper efficiency optimization is carried out for light and heavy load scenarios for variations in supply by varying the duty cycle of switching device. The primary design objective is to maintain the load due to dynamic changes in load. A Fuzzy logic approach for DC-DC buck converter is applied to validate the proposed methods in a Zero Current Switching (ZCS Quasi Resonant (QR Buck Converter which is operated in Half – wave (HW mode at higher frequencies to substantially reduce switching loss and hence attain higher efficiency and power density. Analysis is done in four modes using an unified Generalized State Space Averaging (GSSA technique to obtain its mathematical model and this technique focus mainly on the low frequency behaviour of the circuit, giving a low order representation.

M. A. Panneerselvam

2012-07-01

134

Analysis and Design of a Bidirectional Isolated DC-DC Converter for Fuel Cell and Super-Capacitor Hybrid System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Electrical power system in future uninterruptible power supply (UPS) or electrical vehicle (EV) may employ hybrid energy sources, such as fuel cells and super-capacitors. It will be necessary to efficiently draw the energy from these two sources as well as recharge the energy storage elements by the DC bus. In this paper, a bidirectional isolated DC-DC converter controlled by phase-shift and duty cycle for the fuel cell hybrid energy system is analyzed and designed. The proposed topology mini...

Zhang, Zhe; Ouyang, Ziwei; Thomsen, Ole Cornelius; Andersen, Michael A. E.

2011-01-01

135

Digital Simulation of Closed Loop Zvs-Zcs Bidirectional Dc-Dc Converter for Fuel Cell and Battery Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A closed loop ZVS-ZCS bidirectional dc-dc converter is modeled and appropriate digital simulations are provided. With the ZVS-ZCS concept, the MATLAB simulation results of application to a fuel cell and battery application have been obtained whenever the input voltage exceeds the given 24V, at that time the load voltage will change from 180V to 230V. But due to this usage the load is disturbed and there is instability in the model. Using closed loop the output voltage is stabilized.

Subrahmanya Kumar Bhajana, V. V.; Rama Reddy, S.

2010-01-01

136

Swarming Speed Control for DC Permanent Magnet Motor Drive via Pulse Width Modulation Technique and DC/DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available This study presents an approach for the speed control of a permanent magnet DC motor drive via Pulse Width Modulation (PWM technique and a DC/DC converter. The Particle Swarm Optimization (PSO technique is used to minimize a time domain objective function and obtain the optimal controller parameters. The performance of the proposed technique has been evaluated using various types of disturbances including load torque variations. Simulation results illustrate clearly the robustness of the controller and validity of the design technique for controlling the speed of permanent magnet motors.

A.S. Oshaba

2013-05-01

137

SPECTRAL ANALYSIS OF BUCK AND SEPIC CONVERTERS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Switched mode power converters generate harmonic currents, which will be injected into the utility grid, causing distortion of the utility waveform. They also become a source for the generation of EMI, which may affect the communication systems. This work is about the design and evaluation of the two most frequently used SMPS used in step down mode of operation: the Buck converter and the Sepic converter working in step-down mode of operation. These converters were designed using optimized eq...

CHAKIB ALAOUI

2011-01-01

138

Simulation and Implementation of Soft-Switched Interleaved DC-DC Boost Converter for Fuel Cell Systems  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a soft-switched Interleaved DC-DC Boost Converter (IBC for fuel cell is simulated and implemented. The proposed two-phase IBC circuit consists of two identical boost converter connected in parallel and are controlled by interleaved switching signals. But in the conventional IBC switching loss increases with the number of switching devices. To solve this problem, this paper has proposed a soft switched IBC. Detailed analysis has been done to investigate the benefits of soft-switched IBC compared to that of conventional uncoupled and directly coupled IBC. The converter circuit is constructed using power MOSFET as power switch. The PWM is generated by PIC18F4450 microcontroller. In this paper, the analysis of the converter is presented which is verified by the results of simulation and experimentation.

R. Seyezhai

2012-06-01

139

Simulation and Implementation of Soft-Switched Interleaved DC-DC Boost Converter for Fuel Cell Systems  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a soft-switched Interleaved DC-DC Boost Converter (IBC for fuel cell is simulated and implemented. The proposed two-phase IBC circuit consists of two identical boost converter connected in parallel and are controlled by interleaved switching signals. But in the conventional IBC switching loss increases with the number of switching devices. To solve this problem, this paper has proposed a soft switched IBC. Detailed analysis has been done to investigate the benefits of soft-switched IBC compared to that of conventional uncoupled and directly coupled IBC. The converter circuit is constructed using power MOSFET as power switch. The PWM is generated by PIC18F4450 microcontroller. In this paper, the analysis of the converter is presented which is verified by the results of simulation and experimentation.

R. Seyezhai

2012-09-01

140

Decoupled Power Solution for Dual-input Isolated DC-DC Converters Using Four Quadrants Integrated Transformers (FQIT)  

DEFF Research Database (Denmark)

A common limitation of power coupling effect in some known multiple-input dc-dc converters has been addressed in many literatures. In order to overcome this limitation, a new concept for decoupling the primary windings in the integrated multiple-winding transformers based on 3-dimensional (3D) space orthogonal flux is proposed in this paper. And thus a new geometry core and relative winding arrangements are proposed in accordance with the rthogonal flux decoupling technology. Due to the four secondary windings are arranged in a quadratic pattern at the base core plate with the two perpendicular primary windings, a name of “four quadrants integrated transformers” (FQIT) is therefore given to the proposed construction. Since the two primary windings are uncoupled, the FQIT allows the two input power stages to transfer the energy into the output load simultaneously or at any timemultiplexing scheme, which can optimize the utilization of diversified power energy sources, simplify the system structure, improve the flexibility and reduce the overall cost, so they are attractive for the hybrid renewable power system. Section IV initiates a discussion for the advantages of the FQIT. In order to verify the feasibility of the FQIT in multiple-input converter, a dual-input isolated boost dc-dc converter employing with the FQIT is designed and tested. The results have excellently demonstrated that the two input power stages can be operated independently and the correctness of all the analysis in the paper.

Ouyang, Ziwei; Andersen, Michael A. E.

2012-01-01

 
 
 
 
141

Circuit Simulation for Solar Power Maximum Power Point Tracking with Different Buck-Boost Converter Topologies  

Directory of Open Access Journals (Sweden)

Full Text Available The power converter is one of the essential elements for effective use of renewable power sources. This paper focuses on the development of a circuit simulation model for maximum power point tracking (MPPT evaluation of solar power that involves using different buck-boost power converter topologies; including SEPIC, Zeta, and four-switch type buck-boost DC/DC converters. The circuit simulation model mainly includes three subsystems: a PV model; a buck-boost converter-based MPPT system; and a fuzzy logic MPPT controller. Dynamic analyses of the current-fed buck-boost converter systems are conducted and results are presented in the paper. The maximum power point tracking function is achieved through appropriate control of the power switches of the power converter. A fuzzy logic controller is developed to perform the MPPT function for obtaining maximum power from the PV panel. The MATLAB-based Simulink piecewise linear electric circuit simulation tool is used to verify the complete circuit simulation model.

Jaw-Kuen Shiau

2014-08-01

142

New non-linear control strategy for non-isolated DC/DC converter with high voltage ratio  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a non-isolated DC/DC converter with high voltage ratio is proposed to allow the interface between a low voltage power source like fuel cell and a high voltage DC bus. To take into account the low voltage-high density characteristics of power sources, a cascaded structure composed of two sub-converters has been chosen and allows obtaining a high voltage ratio. The choice of each sub-converter is based on the requirements of the source and its performances. Consequently, we have chosen a three-interleaved boost converter as the 1st sub-converter whereas the 2nd sub-converter is a three-level boost converter. The control of the whole system is realized thanks to energetic trajectories planning based on flatness properties of the system. The control of both the current and the balance of voltage across the output serial capacitors of the three-level boost converter is ensured by non-linear controllers based on a new non-linear model. Experimental results allow validating the proposed power architecture and its associated control. (author)

Shahin, A.; Huang, B.; Martin, J.P.; Pierfederici, S.; Davat, B. [Groupe de Recherche en Electronique et en Electrotechnique de Nancy - INPL - Nancy Universite, 2, Avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy Cedex (France)

2010-01-15

143

Dual-Input Isolated Full-Bridge Boost DC-DC Converter Based on the Distributed Transformers  

DEFF Research Database (Denmark)

In this paper, a new two-input isolated boost dc-dc converter based on a distributed multi-transformer structure which is suitable for hybrid renewable energy systems is investigated and designed. With a novel transformer winding-connecting strategy, the two input ports can be decoupled completely, so the proposed converter can draw the power from the two different dc sources, which have low output voltage, and transfer it to the dc bus, which has high voltage, separately or simultaneously. The detailed operation principles of the proposed converter have been analyzed in the dual-input mode and the single-input mode, respectively. The main advantage of the proposed topology is that the four transformers and the secondary rectifiers are fully utilized whether the converter is connected with two input power sources or only one input. Although the four transformers are employed, the nominal powers of each transformer and rectifier are both reduced by four times. Furthermore, some special issues on converter design, such as increasing number of the input ports, the magnetic integration and the ground loop decoupling are discussed. A 2 kW prototype was built and tested. Experiments on the converter’s steady-state and transient operations verified the validity of the analysis and design.

Zhang, Zhe; Thomsen, Ole Cornelius

2012-01-01

144

Analysis and Design of Bi-Directional DC-DC Converter in the Extended Run Time DC UPS System Based on Fuel Cell and Supercapacitor  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract-In this paper, an extended run time DC UPS system structure with fuel cell and supercapacitor is investigated. A wide input range bi-directional dc-dc converter is described along with the phase-shift modulation scheme and phase-shift with duty cycle control, in different modes. The delivered power and peak current are analyzed and calculated. The key parameters of the bi-directional dc-dc converter, the relationships between the input voltage, phase-shift angle,...

Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.; Schmidt, Jacob D.; Nielsen, Henning R.

2009-01-01

145

Bi-Directional Edge-Resonant Switched Capacitor Cell-Assisted Soft-Switching PWM DC–DC Converter For Renewable Energy Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a soft-switching pulse width modulation (PWM) non-isolated bi-directional dc–dc converter embedding an edge-resonant switched capacitor (ER-SWC) cell. The conceptual dc–dc converter treated herein can achieve high-frequency zero-current soft-switching turn-on and zero-voltage soft-switching turn-off operations in the active switches. Those advantageous properties enable a wide range of soft-switching operations together with a high-voltage step- up conversion ratio wit...

Saritha Thomas; Rabiya Rasheed

2014-01-01

146

TID and Displacement Damage Effects in Vertical and Lateral Power MOSFETs for Integrated DC-DC Converters  

CERN Document Server

TID and displacement damage effects are studied for vertical and lateral power MOSFETs in five different technologies in view of the development of radiation-tolerant fully integrated DC-DC converters. Investigation is pushed to the very high level of radiation expected for an upgrade to the LHC experiments. TID induces threshold voltage shifts and, in n-channel transistors, source-drain leakage currents. Wide variability in the magnitude of these effects is observed. Displacement damage increases the on-resistance of both vertical and lateral high-voltage transistors. In the latter case, degradation at high particle fluence might lead to a distortion of the output characteristics curve. HBD techniques to limit or eliminate the radiation-induced leakage currents are successfully applied to these high-voltage transistors, but have to be used carefully to avoid consequences on the breakdown voltage.

Faccio, F; Michelis, S; Faccio, Federico; Fuentes, C; Allongue, B; Sorge, R; Orlandi, S

2010-01-01

147

Battery charging characteristics in small scaled photovoltaic system using resonant DC-DC converter with electric isolation  

International Nuclear Information System (INIS)

The solar energy has been drawing attention of the whole world as a clean and infinite energy, since the globe resource, the globe ecology and so on came into question. The wide applications of the solar energy are being expected in a range from electric power plants to household systems. But the output power induced in the photovoltaic modules is influenced by an intensity of the solar radiation, a temperature of the solar cells and so on, so the various useful forms of the solar energy are being proposed for a purpose of stable power supply. a system described in this paper is a small scaled photovoltaic system with storage batteries. This paper describes the theoretical analyses of the photovoltaic system using a resonant DC-DC converter in order to clarify a desirable circuit condition, besides the experimental results of the battery charging characteristics are presented

148

Quasi-Periodicity and Border-Collision Bifurcations in a DC-DC Converter with Pulsewidth Modulation  

DEFF Research Database (Denmark)

The paper considers the dynamics of a dc-dc converter with pulsewidth modulation. The typical scenario for the transition to chaos in such systems proceeds via quasi-periodicity, resonance cycles, and torus destruction. Detailed bifurcation analysis shows that the resonance solutions arise via border-collision bifurcations (BCB) on a two-dimensional torus. The arrangement of the resonance domains within the parameter plane is related to the Farey series, and their internal structure is described. It is shown that transitions to chaos mainly occur through finite sequences of BCB. Some other possible causes of complex dynamics are considered, including a subcritical Neimark-Sacker (Andronov-Hopf) bifurcation and the associated hysteretic phenomena.

Zhusubalaliyev, Zh. T.; Soukhoterin, E.A.

2003-01-01

149

Design, Analysis and Implementation of a new topology of multi phase synchronous buck converter under current mode control  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a new PWM Multi phase DC-DC converter under current mode control with an auxiliary circuit which provides zero voltage switching in order to meet the power supply requirements of the processors of modern electronic equipments like laptops, mobiles, and PDAs etc which require more than 70 A current, lower voltage and better transient response.The multi phase topology benefits in high current, good efficiency and better current transient response. High current multi phase buck converters found applications in advanced data control, solid state lasers, communication equipment and Pentium processors etc. In this paper designed of three phase DC-DC converter 100W, 12V/1V under current mode control is discussed in detail and the simulation results are presented to support the theoretical analysis.

Nittala S K Sastry

2012-06-01

150

Stability analysis of a high-step-Up DC grid-connected two-stage boost DC-DC converter  

Directory of Open Access Journals (Sweden)

Full Text Available High conversion ratio switching converters are used whenever there is a need to step-up dc source voltage level to a much higher output dc voltage level such as in photovoltaic systems, telecommunications and in some medical applications. A simple solution for achieving this high conversion ratio is by cascading different stages of dc-dc boost converters. The individual converters in such a cascaded system are usually designed separately applying classical design criteria. However these criteria may not be applicable for the complete cascaded system . This paper first presents a glimpse on the bifurcation behavior that a cascade connection of two boost converters can exhibit. It is shown that the desired periodic orbit can undergo period doubling leading to subharmonic oscillations and chaotic regimes. Then, in order to simplify the analysis the second stage is considered as constant current sink and design-oriented analysis is carried out to obtain stability boundaries in the parameter space by taking into account slope interactions between the state variables in the two-different stages.

El Aroudi A.

2014-01-01

151

SIDO Buck Converter with Independent Outputs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The portable electronics market is rapidly migrating towards more compact devices requiring multiple high-integrity high-efficiency voltage supplies for empowering the systems. This paper demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3V. The main target is low cross regulation between the two outputs to supply independent load current levels while maintaining desired output voltage values well within a ripple...

Eachempatti, H.; Ganta, S.; Silva-marti?nez, Jose?; Marti?nez Garci?a, Herminio

2010-01-01

152

Efficiency and hardware comparison of analog control-based and digital control-based 70 W two-stage power factor corrector and DC-DC converters  

DEFF Research Database (Denmark)

A comparison of an analog and a digital controller driven 70 W two-stage power factor corrector converter is presented. Both controllers are operated in average current-mode-control for the PFC and peak current control for the DC-DC converter. Digital controller design and converter modeling is described. Results show that digital control can compete with the analog one in efficiency, PFC and THD.

Török, Lajos; Munk-Nielsen, Stig

2011-01-01

153

DC-DC Converters Using PID Controller and Pulse Width Modulation Technique  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a boost converter along with a flyback converter. The Zero Voltage Switching (ZVS technique is used to achieve soft switching. A bidirectional boost converter is connected with an output module as a Parallel Input Serial Output configuration. The flyback converter with Voltage Doubler Rectifier (VDR acts as an output module. This connection makes a bidirectional boost converter an active clamp circuit which is connected to the output side in order to extend the step up ratio. A converter with active clamp technique is used to recycle the leakage energy, to eliminate voltage spike due to coupled inductors and also to provide a mechanism to achieve ZVS. To overcome the efficiency degradation during light load due to load dependent soft switching of the ZVS, a control method using Pulse Width Modulation (PWM proportional to the load current is used.

R.Sudha

2014-01-01

154

Closed Loop DC-DC Boost Converter with Inverter for Small Scale Generation Plant  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper implements the single phase two level PWM inverter by using DC converter. DC voltage is boosted using dc to dc boost converter with the help of close loop topology. Here converter will be used to convert 24 volts DC voltage to 373 volts. The boosted DC voltage is converted in to AC with help of PWM inverter. Boosted DC voltage is fed with the inverter and that converts DC voltage into AC voltage. The cascaded H-Bridge type of inverter is used to achieve AC output voltage. The output of inverter is given to low-pass filter which will give 260 volts (RMS AC , 50Hz pure sinusoidal output voltage & finally this output is given to the load.

Manish Agarwal

2014-09-01

155

Isolated Full Bridge Boost DC-DC Converter Designed for Bidirectional Operation of Fuel Cells/Electrolyzer Cells in Grid-Tie Applications  

DEFF Research Database (Denmark)

Energy production from renewable energy sources is continuously varying, for this reason energy storage is becoming more and more important as the percentage of green energy increases. Newly developed fuel cells can operate in reverse mode as electrolyzer cells; therefore, they are becoming an attractive technology for energy storage grid-tie applications. In this application dc-dc converter optimization is very challenging due to the large voltage range that the converter is expected to operate. Moreover, the fuel-electrolyzer cell side of the converter is characterized by low voltage and high current. Dc-dc converter efficiency plays a fundamental role in the overall system efficiency since processed energy is always flowing through the converter; for this reason, loss analysis and optimization are a key component of the converter design. The paper presents an isolated full bridge boost dc-dc converter (IFBBC) designed for this new application focusing on losses analysis. The system topology is briefly discussed and the major concerns related to the system, cells stacks and converter operating points are analyzed. The dc-dc converter losses are modeled and presented in detail; the analysis is validated on adc-dc converter prototype rated at 6 kW 30-80 V 0-80 A on the low voltage side and 700-800 V on the high voltage side (for a grid-tie application). The prototype is based on fully planar magnetic, Si MOSFETs, Si IGBTs and SiC diodes; efficiencies up to ~96.5% and ~97.8% were demonstrated depending on the converter operating point.

Pittini, Riccardo; Zhang, Zhe

2013-01-01

156

DC-DC Converters in Wind Systems for Micro-generation: A Systematic Review  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a literature review analyzing four topics concerning wind systems for micro-generation: system topologies, system modeling, power converters design, and power converter controllers. The review also reveals the open research problems in the literature, and the opportunities to improve commonly adopted solutions.

Carlos Alejandro Ramírez

2014-08-01

157

High efficiency isolated DC/DC converter inherently optimized for fuel cell applications  

DEFF Research Database (Denmark)

The isolated full-bridge boost converter has been suggested as the best choice for fuel cell applications. Comparisons have been carried out in the literature using both stress factors and experimental verified designs to determine the optimal converter. Never the less, this paper suggests a different topology not previous used for fuel cell applications with some clear advantages. Taking into account the I-V characteristics of the fuel cell only emphasized the performance of the proposed converter and reveals its self as an optimal candidate for the fuel cell application.

Petersen, Lars Press; Jensen, Lasse Crone

2013-01-01

158

Modeling and control of isolated full bridge boost DC-DC converter implemented in FPGA  

DEFF Research Database (Denmark)

In this paper an isolated full bridge boost converter (IFBC) firstly is modeled. In the modeling part, a small signal equivalent of the converter is developed. From the small signal model, the converter transfer function is derived. Based on the obtained transfer function, challenges of controller design are discussed. In the next step a digital PI controller is designed and implemented in a FPGA to control the output voltage. Using the injection transformer method the open loop transfer function in closed loop is measured and modeling results are verified by experimental results. © 2013 IEEE.

Taeed, Fazel; Nymand, M.

2013-01-01

159

Design of DC-DC Converter and its Control for a Wind Generation System Connected to an Isolated Load  

Directory of Open Access Journals (Sweden)

Full Text Available A method to design a Buck converter and its control, which are associated to a wind generation system that is feeding an isolated load, is presented in this paper. To design the converter a Thevenin equivalent is deduced, which represents the behavior of the wind turbine, the permanent magnet synchronous generator, and the rectifier. The design of the converter elements guarantees input/output voltages and inductor current ripples of 5 % or less. The output voltage control is developed with a proportional-integral-derivative controller and as design criteria a damping of 0,707 and cutoff frequency of 1/5 converter commutation frequency are selected. The designed controller regulates the output voltage faced load perturbations and wind speed variations. 

Carlos A. Ramírez Gómez

2013-11-01

160

State Space Analysis and Modeling of DC-DC Converter With High Frequencies  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The design of the control law for power converter can be a complex task especially when high performance is required against load and line variations. This difficulty can further increase in the presence of input filters. Which are intentionally under damped to decrease the converter losses. In such cases, the peak current mode control facilitates the design of control law. The usual approach for the modeling of this type of control assumes constant current ripples in smoothing inductance. Ho...

A Suresh Kumar, M. Sreenu

2012-01-01

 
 
 
 
161

Design and Control of a Multiple Input DC/DC Converter for Battery/Ultra-capacitor Based Electric Vehicle Power System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi-input converter is capable of bi-directional operation and is responsible for power diversification and optimization. A fixed switching frequency strategy is considered to control its operating modes. A portio...

Schaltz, Erik; Li, Zhihao; Onar, Omer; Khaligh, Alireza

2009-01-01

162

An Effective High Step-Up Interleaved DC-DC Converter Photovoltaic Grid Connection System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Within the photovoltaic (PV) power generation systems in the market, the ac PV module has shown obvious growth. However, a high voltage gain converter is concentrate for the module’s grid connection with dc-ac inverter. This paper proposed a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and numerous turns-ratio of a couple...

G. Lakpathi,; S. ManoharReddy,; K. Lakshmi Ganesh,; G. Satyanarayana,

2013-01-01

163

Analysis and Design of a Bidirectional Isolated DC-DC Converter for Fuel Cell and Super-Capacitor Hybrid System  

DEFF Research Database (Denmark)

Electrical power system in future uninterruptible power supply (UPS) or electrical vehicle (EV) may employ hybrid energy sources, such as fuel cells and super-capacitors. It will be necessary to efficiently draw the energy from these two sources as well as recharge the energy storage elements by the DC bus. In this paper, a bidirectional isolated DC-DC converter controlled by phase-shift and duty cycle for the fuel cell hybrid energy system is analyzed and designed. The proposed topology minimizes the number of switches and their associated gate driver components by using two high frequency transformers which combine a half-bridge circuit and a full-bridge circuit together on the primary side. The voltage doubler circuit is employed on the secondary side. The current-fed input can limit the input current ripple that is favorable for fuel cells. The parasitic capacitance of the switches is used for zero voltage switching (ZVS). Moreover, a phase-shift and duty cycle modulation method is utilized to control thebidirectional power flow flexibly and it also makes the converter operate under a quasi-optimal condition over a wide input voltage range. This paper describes the operation principle of the proposed converter, the ZVS conditions and the quasi-optimal design in depth. The design guidelines and considerations about the transformers and other key components are given. Finally, a 1- kW 30~50-V-input 400-V-output laboratory prototype operating at 100 kHz switching frequency is built and tested to verify the effectiveness of the presented converter.

Zhang, Zhe; Ouyang, Ziwei

2012-01-01

164

A New Active Soft Switching Technique for Pulse Width Modulated Full Bridge DC-DC Converters  

Directory of Open Access Journals (Sweden)

Full Text Available A new active soft switching circuit for Zero Voltage Switched Pulse Width Modulated (ZVS-PWM full bridge converter is presented in this paper. The proposed circuit has two auxiliary circuit cells (Auxiliary circuit cell-1, Auxiliary circuit cell-2, one for each ground referred active switch. Auxiliary circuit cell consists of an active switch, a diode, a resonant inductor and a capacitor, and a coupled winding derived from main power transformer. Auxiliary circuit when gated properly creates zero voltage across the main switch during its turn-on. Winding coupled to the power transformer helps in resetting auxiliary inductor current to zero and hence turn-off of auxiliary switch is lossless. Steady state operation of proposed circuit with necessary analytical expressions is presented. Circuit simulation results of the proposed active soft switched ZVS-PWM full bridge converter are presented.

Naga Brahmendra Yadav Gorla

2014-02-01

165

Design and Implementation of high frequency transformer for SMPS Based flyback DC-DC converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In switch mode power supplies (SMPS), flyback converters are very popular because of, design simplicity, low cost, multiple isolated outputs, high output voltages and high efficiency. They are preferred especially for low power applications. In this paper we have presented the design of transformer for variable DC input (18V to 60V) to 12V DC output. And observed the wave form across the switch, primary & secondary of the transformer.

Prashanth R.S.; Tavade, C. M.; Deshpande, L. M.; Hameed Miyan

2012-01-01

166

Design and Implementation of high frequency transformer for SMPS Based flyback DC-DC converter  

Directory of Open Access Journals (Sweden)

Full Text Available In switch mode power supplies (SMPS, flyback converters are very popular because of, design simplicity, low cost, multiple isolated outputs, high output voltages and high efficiency. They are preferred especially for low power applications. In this paper we have presented the design of transformer for variable DC input (18V to 60V to 12V DC output. And observed the wave form across the switch, primary & secondary of the transformer.

Prashanth R.S.

2012-12-01

167

A Novel Soft Computing Based Algorithm for the Control of Dynamic Uncertain Systems - An Application to DC-DC Converters  

Directory of Open Access Journals (Sweden)

Full Text Available Both Soft computing based controllers and sliding mode controllers have been utilized to regulate theoutput voltage of dc-dc converters in response to changes in the load and the input voltage. Althoughboth control techniques possess desirable characteristics, they have disadvantages which prevent themfrom being applied extensively. Many researchers have proposed the combination of sliding modecontrol and Soft computing based control to combine the advantages of both control techniques. Inliterature survey, it is found that the combination of the methods are proposed so that sliding modealgorithm is used in the design of Soft computing based controllers and the inputs to the controller areerror and change in error and the inherent stability property of sliding mode controller is not utilized.This paper presents a novel soft computing based sliding mode controller in which inputs are switchingfunction and change in switching function which combines the advantages of soft computing basedcontrollers, sliding mode controllers and integral controllers. Since soft computing is used in the designof sliding mode controller, the stability of the proposed controller is assured. In addition, it is well suitedfor digital control design and implementation. The proposed controller has been designed for a buckconverter and the controller is able to obtain the desired transient response without causing chatteringand error under steady-state conditions. The proposed controller is able to give robust performance interms of rejection to input voltage variations and load variations.

Abdul kareem

2011-05-01

168

Transformer less DcDc Converter with high Step up Voltage gain Method  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new circuit is proposed for a steep step-up of the line voltage. It integrates a switched-capacitor (SC) circuit with in a boost converter. An SC circuit can achieve any voltage ratio, allowing for a boost of the input voltage to high values. It is un regulated to allow for a very high efficiency. The boost stage has a regulation purpose. It can operate at a relatively low duty cycle, thus avoiding diode-reverse recovery problems. The new circuit is not cascadeinterconnection of the two pow...

K Raja Gopal, B. Gavaskar Reddy

2011-01-01

169

A prototype of a fuel cell PEM emulator based on a buck converter  

International Nuclear Information System (INIS)

After a brief introduction about fuel cell systems, and their modelling, this paper proposes a possible solution to emulate a proton exchange membrane fuel cell (PEM-FC) system by using a DC-DC buck converter. The fuel cell system, including all its auxiliaries and related control systems, is emulated by a buck converter realized experimentally and controlled in the DSPACE environment. The realization of the buck converter allows the behaviour of any fuel cells to be easily emulated since only the modification of the control law of the switch is necessary. The proposed emulator can be applied easily to other fuel cell systems if the polarization curve has the same current rate and maximum power. In this way it is possible to utilize the converter and perform the necessary tests to optimize a fuel cell system by avoiding the waste of hydrogen and the purchase of cells as well as any cell damage. With regard to current other types of emulators, the one presented here has the following characteristics: (1) all the auxiliaries of the system have been considered, each including its own control system, as in a real FCS, (2) the converter is a classical buck converter with a free-wheeling diode and is designed to have a high bandwidth and to be practically always in conduction mode (discontinuous mode appears only at very low currents) (3) the voltage control is made by a space-state controller, able to fix properly the closed loop poles of the system, thus guaranteeing the oles of the system, thus guaranteeing the desired bandwidth of the control system and (4) it can be used in laboratory as a stand-alone low-cost system for design and experimental purposes.

170

Advanced Energy Conversion System Using Sinusoidal Voltage Tracking Buck-Boost Converter Cascaded Polarity Changing Inverter  

Science.gov (United States)

This paper presents an advanced power converter employs a sinusoidal voltage absolute value tracking buck-boost DC-DC converter in the first power processing stage and a polarity changing full-bridge inverter in the second stage. The proposed power conversion system has the capability of delivering sinusoidal output and input current with unity power factor and good output voltage regulation. Consequently, the complete voltage regulator system, which is mainly suitable for new energy generation systems as well as energy storage systems, can be constructed compactly and inexpensively without DC link electrolytic capacitor. Also, the paper presents an auxiliary passive resonant circuit for soft switching operation. Simulation results using PSIM software are presented to verify the operation principles and feasibility of the proposed power conversion system.

Ahmed, Nabil A.

2011-06-01

171

Micro-Fabrication and Circuit Optimization for Magnetic Components of High-Efficiency DC-DC Converters  

Science.gov (United States)

Magnetic components are essential parts of power converters. Inductors with magnetic cores are investigated. An eddy current loss model for pot-core inductors is developed with finite elemental analysis (FEA). The reliability of inductors using magnetic cores in a high-temperature environment is investigated. Working in up to 150°C circumstance for a short periods is not destructive for the inductors. Optimization of toroidal inductors in a DC-DC converter is investigated. Parasitic capacitance and the capacitive loss in toroidal inductors are modeled. Standard circuit optimization is performed to explore the energy conversion efficiency of the toroidal inductors. Thermal analysis, light-load efficiency and relative permeability of the toroidal inductor design are also investigated. The toroidal inductor can achieve about 85% efficiency for 3 A DC current and 1 W/mm2 power density. Inductor-only efficiency of toroidal inductors is investigated with revised model. At 100 MHz operating frequency, toroidal inductors can achieve more than 97% inductor efficiency with power density range of 0.7 W/mm2 to 6 W/mm2. The performance of our nanograngular magnetic core is dependent on the angle of the poling magnetic field compared to the field during operation. Experiments on a serious of samples show that the poling angle can deviate by up to 15 degrees from ideal with only a small penalty in performance. The field-angle experiment is intended to prove integrated toroidal inductor process possible. A magnetic fixture model is proposed for large-scale toroidal inductor processing.

Tian, Rui

172

Multiple low frequency dual reference PWM control of a grid connected photovoltaic three phase NPC inverter with DC/DC boost converter  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.

Mechouma Rabiaa

2014-01-01

173

Analysis and design of a parallel-connected single active bridge DC-DC converter for high-power wind farm applications  

DEFF Research Database (Denmark)

This paper presents a parallel-connected Single Active Bridge (SAB) dc-dc converter for high-power applications. Paralleling lower-power converters can lower the current rating of each modular converter and interleaving the outputs can significantly reduce the magnitudes of input and output current ripples without increasing switching losses or device stresses. Analysis of both the input and output current characteristics and design aspects of the transformer, the filter inductor, and the input and output filter capacitors will be presented. Considering the high maintenance cost and fault tolerant requirements, this modular converter concept is expected to be highly beneficial especially for the offshore wind farm application.

Park, Kiwoo; Chen, Zhe

2013-01-01

174

Analysis and Design of Bi-Directional DC-DC Converter in the Extended Run Time DC UPS System Based on Fuel Cell and Supercapacitor  

DEFF Research Database (Denmark)

Abstract-In this paper, an extended run time DC UPS system structure with fuel cell and supercapacitor is investigated. A wide input range bi-directional dc-dc converter is described along with the phase-shift modulation scheme and phase-shift with duty cycle control, in different modes. The delivered power and peak current are analyzed and calculated. The key parameters of the bi-directional dc-dc converter, the relationships between the input voltage, phase-shift angle, ratio of the transformer and leakage inductance are analyzed and optimized. Build the system mathematic model and a novel input voltage combined with load current feedback using PI controller with anti-windup scheme to realize closed-loop control of the whole system, and verify the feasibility of the control scheme proposed by simulation. A 1kW prototype controlled by TMS320F2808 DSP is implemented and tested. Experimental results show the validity of design.

Zhang, Zhe; Thomsen, Ole Cornelius

2009-01-01

175

1 kW, 9 kV dc-dc converter module with time-sharing control of output voltage and input current  

Energy Technology Data Exchange (ETDEWEB)

The paper describes a dc-dc power module based on a single-stage current-fed converter structure. Control is made according to a time-sharing strategy allowing simultaneous regulation of output voltage and input current. This solution is suitable for high-performance space and avionic applications, giving high efficiency, compactness, and accuracy, speed and robustness of control. Theoretical analysis, design criteria, and experimental results are reported. Application to radar supplies is discussed.

Borgatti, R.; Stefani, R.; Bressan, O.; Bicciato, F. [F.I.A.R. Electronic Systems Group, Milan (Italy). Avionics Div.; Tenti, P.; Rossetto, L. [Univ. of Padova (Italy). Dept. of Electrical Engineering

1993-10-01

176

The design and development of a novel flyback planar transformer for high frequency switch mode DC-DC converter applications - part 1  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this work a step by step planar transformer design proccdare for Flybock switch-mode DC-DC converter application is presented. This transformer has a maximum dimention of 2cm x 2cm x 0.4cm aiming to achieve an efficiency of 99% at an operating frequency of 500kHz. This planar transformer is designed specially for thick film technology development.

Arshak, Khalil; Almukhtar, Basil

2000-01-01

177

Improved Dynamic Response of Buck Converter using Fuzzy Controller  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents comparative performance of Buck Converter in both open as well as closed loop. With the help state equations Mathematical Model of Buck Converter is designed in MATLAB/SIMULINK. The obtained output response of open loop Buck Converter is sluggish, not optimum and consists of peak overshoots. PI Controller is used in closed loop model of Buck Converter. Output Voltage is compared with a reference signal, which then is processed through a controller (PI/Fuzzy. The obtained signal is superimposed with a carrier signal and given to switching device used. To further optimize the performance of Buck Converter and eliminate the peak overshoot present in output response, Fuzzy controller is used. Here Suguno type Fuzzy is used.

Nagulapati Kiran

2014-03-01

178

Digital Linear and Nonlinear Controllers for Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Both linear PID controllers and fuzzy controllers are designed and implemented for a buck converter. Comparison between the two controllers is made in the aspect of design, implementation and experimental results. Design of fuzzy controllers is based on heuristic knowledge of the converter and tuned using trial and error, while the design of linear PID and PI controllers is based on the frequency response of the buck converter. Implementation of linear controllers is quite straightforward, wh...

Shyama M; Swaminathan, P.

2012-01-01

179

Design and Control of a Multiple Input DC/DC Converter for Battery/Ultra-capacitor Based Electric Vehicle Power System  

DEFF Research Database (Denmark)

Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi-input converter is capable of bi-directional operation and is responsible for power diversification and optimization. A fixed switching frequency strategy is considered to control its operating modes. A portion of New York City Cycle that includes these operation modes is used to perform the analyses.

Schaltz, Erik; Li, Zhihao

2009-01-01

180

Two phase interleaved buck converter for driving high power LEDs  

DEFF Research Database (Denmark)

The goal of this paper is to evaluate an interleaved buck topology for driving high current light-emitting diodes. Low output capacitor value allows the use of non-electrolytic capacitors extending the lifetime of the converter. Converter is operated as a constant, regulated current source which increases luminous efficacy of LED compared to PWM dimmed system. Because of the low dynamic resistance of LEDs the duty cycle of the converter does not change greatly with controlled current. By setting the input voltage of the buck converter to around twice the voltage of diode strings, converter can be operated close to the 50% duty cycle, where the ripple attenuation is the highest.

Beczkowski, Szymon; Munk-Nielsen, Stig

2011-01-01

 
 
 
 
181

Optimal Design of a Push-Pull-Forward Half-Bridge (PPFHB) Bidirectional DC–DC Converter With Variable Input Voltage  

DEFF Research Database (Denmark)

This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high-frequency transformer; this structure minimizes the number of the switching transistors and their associate gate driver components. With phase-shift control strategy, all the switches are operated under zero-voltage switching (ZVS) condition. Furthermore, in order to optimize the converter performance and increase efficiency, optimal design methods and criteria are investigated, including coupled inductors design, bidirectional power flow analysis, harmonics analysis, and ZVS range extension. Based on all the optimal parameters, higher efficiency can be achieved. Finally, prototypes are built in laboratory controlled by digital signal processor for comparison purpose. Detailed test results verify the theoretical analysis and demonstrate the validity of optimization design method.

Zhang, Zhe; Thomsen, Ole Cornelius

2012-01-01

182

Two-Phase Interleaved Buck Converter with a new Digital Self-Oscillating Modulkator  

DEFF Research Database (Denmark)

This paper presents a new Digital Self-Oscillating Modulator (DiSOM) for DC/DC converters. The DiSOM modulator alllows the digital control algorithm to sample the output voltage at a sampling frequency higher than the converter switching frequency. This enables higher control loop bandwidth than for traditional digital PWM modulators given a certain switching frequency. A synchronised version of the DiSOM modulator is derived for interleaved converters. A prototype interleaved Buck converter for Point of Load applications has been designed and built to test the performance of DiSOM modulator. The DiSOM modulator and a digital control algorithm have been implemented in an FPGA. Experimental results show that the converter has a very fast transient response when a loadstep is applied to the output. For a loadstep of 50% of nominal output current the output voltage overshoot is less than 2.5% of the nominal output voltage and the settling time is just 8 switching periods.

Jakobsen, Lars TØnnes; Andersen, Michael Andreas E.

2007-01-01

183

Methods of Battery Charging with Buck Converter Using Soft-Switching Techniques  

Directory of Open Access Journals (Sweden)

Full Text Available This paper is a detailed study on methods of battery charging with Buck Resonant converter using soft switching techniques like ZVS and ZCS. This study also presents the circuit configuration with the least components to realize a highly efficient solar energy battery charger with a zero-voltage and zero current switching resonant converter. The high-frequency resonant converter has numerous well-known advantages over the traditional hard-switching converters. The most important advantage is that it offers a lower switching loss and a higher power density. Additionally, the soft switching current waveform characterizes a lower electromagnetic interference (EMI. The operating principles and design procedure of the proposed charger with both zero voltage and zero current are thoroughly analyzed. The optimal values of the resonant components are computed by applying the characteristic curve and electric functions derived from the circuit configuration. Finally, a simulation model is implemented for charger circuit designed for a 12-V 4-Ah lead acid battery using zero voltage and zero current switching and MATLAB/SIMULINK software is used as the simulation tool. The proposed dc?dc battery charger has a straightforward structure, low cost, easy control, and high efficiency. Satisfactory performance is obtained from the experimental results.

S. Abinaya

2011-12-01

184

Computer simulations of optimum boost and buck-boost converters  

Science.gov (United States)

The development of mathematicl models suitable for minimum weight boost and buck-boost converter designs are presented. The facility of an augumented Lagrangian (ALAG) multiplier-based nonlinear programming technique is demonstrated for minimum weight design optimizations of boost and buck-boost power converters. ALAG-based computer simulation results for those two minimum weight designs are discussed. Certain important features of ALAG are presented in the framework of a comprehensive design example for boost and buck-boost power converter design optimization. The study provides refreshing design insight of power converters and presents such information as weight annd loss profiles of various semiconductor components and magnetics as a function of the switching frequency.

Rahman, S.

1982-01-01

185

Single phase AC-DC power factor corrected converter with high frequency isolation using buck converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Single phase ac-dc converters having high frequency isolation are implemented in buck, boost, buck-boost configuration with improving the power quality in terms of reducing the harmonics of input current. The paperpropose the circuit configuration, control mechanism, and simulation result for the single phase ac-dc converter.

R. Ramesh,; Subathra, U.

2014-01-01

186

?uk-Buck Converter for Standalone Photovoltaic System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents MPPT converter for battery charger. The converter combines both ?uk and buck converters to extract the maximum power from the sun while supplying a controlled constant current/voltage to the battery. The topology uses two control signals instead of one control signal; one for tracking the maximum power point, another for charging the battery providing constant current/voltage to the battery. The advantage of this converter is to exploit the maximum power of the PV array a...

El Khateb, Ahmad H.; Nasrudin Abd Rahim; Jeyraj Selvaraj

2013-01-01

187

Soft-Switched Dual-Input DC-DC Converter Combining a Boost-Half-Bridge Cell and a Voltage-Fed Full-Bridge Cell  

DEFF Research Database (Denmark)

This paper presents a new zero-voltage-switching (ZVS) isolated dc-dc converter which combines a boost halfbridge (BHB) cell and a full-bridge (FB) cell, so that two different type of power sources, i.e. both current-fed and voltage-fed, can be coupled effectively by the proposed converter for various applications, such as fuel cell and super-capacitor hybrid energy system. By fully using two high frequency transformers and a shared leg of switches, number of the power devices and associated gate driver circuits can be reduced. With phase-shift control, the converter can achieve ZVS turn-on of active switches and zero-current switching (ZCS) turn-off of diodes. In this paper, derivation, analysis and design of the proposed converter are presented. Finally, a 25~50 V input, 300~400 V output prototype with a 600 W nominal power rating is built up and tested to demonstrate the effectiveness of the proposed converter topology.

Zhang, Zhe; Thomsen, Ole Cornelius

2013-01-01

188

Interleaved Boost-Half-Bridge Dual–Input DC-DC Converter with a PWM plus Phase-Shift Control for Fuel Cell Applications  

DEFF Research Database (Denmark)

This paper presents an isolated dual-input DC-DC converter with a PWM plus phase-shift control for fuel cell hybrid energy systems. The power switches are controlled by phase shifted PWM signals with a variable duty cycle, and thus the two input voltages as well as the output voltage can be regulated effectively. By using the second input capacitor and the high side switches as an inherent active clamping circuit, zerovoltage switching (ZVS) for the power MOSFETs on the primary side, and zero-current switching (ZCS) for the diodes on the secondary side are achieved respectively to improve the performance of the proposed PWM converter. The principle of operation is analyzed and some design considerations are discussed. Simulation results using PLECS are given to verify the proposed analysis and design. An experimental converter prototype has been designed, constructed and tested in the laboratory to verify the validity of the theoretical analysis and also demonstrate the converter’s performance over wide variations in input voltage.

Zhang, Zhe; Andersen, Michael A. E.

2013-01-01

189

?uk-Buck Converter for Standalone Photovoltaic System  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents MPPT converter for battery charger. The converter combines both ?uk and buck converters to extract the maximum power from the sun while supplying a controlled constant current/voltage to the battery. The topology uses two control signals instead of one control signal; one for tracking the maximum power point, another for charging the battery providing constant current/voltage to the battery. The advantage of this converter is to exploit the maximum power of the PV array avoiding battery damage caused by variable MPPT voltage. The effectiveness of the proposed converter was tested in simulation in various operating conditions.

Ahmad H. El Khateb

2013-01-01

190

Design of a Fully Integrated Three-Level Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Dynamic response of a converter plays an important role in many applications which change load in a rapid manner, especially in POL (Point of load applicant ions. Here a new method for improving the dynamic response of a converter is presented. Here separate control schemes are implemented during steady state as well as transient load conditions. A three level buck converter topology with fast transient response is discussed here. This topology does not require a soft start up circuitry for three level buck converters. Simulation model is done in Matlab/Simulink and the result shows a great improvement in dynamic response of the system. The 3-level converter enables smaller inductors (1 NH than a buck, while generating a wide range of output voltages compared to a 1/2 model capacitor converter. The test-chip prototype delivers up to 0.85 a load current while generating output voltages from 0.4 to 1.4 V from a 2.4 V input supply. It achieves 77% peak efficiency at power density of 0.1 W/mm and 63% efficiency at maximum power density of 0.3 W/mm.

Y. Neelima*,

2014-08-01

191

Advanced High Power DC-DC Converter using A Novel Type Voltage Source Full-Bridge Soft-Switching PWM Inverter with High Frequency Transformer Link for Arc Welding Applications  

Science.gov (United States)

This paper presents a new circuit topology of full-bridge soft-switching PWM inverter linked DC-DC power converter composed of conventional full-bridge high frequency PWM inverter with high frequency transformer and an active quasi-resonant snubber consisting of an additional power switching device in series with DC busline and a lossless capacitor in parallel with DC busline. Under this proposed high frequency soft-switching PWM inverter linked DC-DC converter, four power switches in the full-bridge arms and DC busline series switch can achieve ZVS at turn-off commutation. By developing the advanced soft-switching PWM high frequency inverter type DC-DC converter, although the conduction power loss of DC busline series power switch increases a little, the total turn-off switching loss of full-bridge high frequency inverter power modules can be sufficiently lowered more and more in the higher frequency range of 60kHz. As a result, when the switching frequency of high frequency inverter power stage using IGBT power modules is designed so as to be more than about 10kHz, the more the switching frequency of inverter increases, the more this high frequency soft-switching DC-DC converter has remarkable advantage as for the power conversion efficiency as compared with the conventional hard-switching PWM inverter DC-DC converter. Its practical effectiveness of high power density and high performance is actually proved for TIG arc welding equipment in industry.

Morimoto, Keiki; Doi, Toshimitsu; Manabe, Haruhiko; Ahmed, Tarek; Hiraki, Eiji; Lee, Hyun-Woo; Nakaoka, Mutsuo

192

Digital Linear and Nonlinear Controllers for Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Both linear PID controllers and fuzzy controllers are designed and implemented for a buck converter. Comparison between the two controllers is made in the aspect of design, implementation and experimental results. Design of fuzzy controllers is based on heuristic knowledge of the converter and tuned using trial and error, while the design of linear PID and PI controllers is based on the frequency response of the buck converter. Implementation of linear controllers is quite straightforward, while implementation of fuzzy controllers has its unique issues. A comparison of experimental results indicates that the performance of the fuzzy controller is superior to that of the linear PID and PI controllers. The fuzzy controller is able to achieve faster transient response, has more stable steady-state response, and is more robust under different operating points.

Shyama M

2012-03-01

193

A 0.35?m 50V CMOS Sliding-Mode Control IC for Buck Converters  

DEFF Research Database (Denmark)

This paper presents a hysteretic (sliding mode) control IC for a buck DC/DC converter for use as an envelope tracking power supply to increase the efficiency of an RF power amplifier. The IC integrates a high-bandwidth error amplifier, a comparator with hysteresis, and a high-side driver for an external N-channel power MOSFET. The total control loop delay using the implemented IC is 35ns, this is shown to be a 30% reduction compared to a state-of-the-art discrete IC based solution. The presented results also show that it is viable to integrate a 100MHz operational amplifier on the same die as a high-voltage MOSFET driver operating with slew rates in excess of 5V/ns. The IC is demonstrated in a tracking power supply with 30W output power and 3?s rise/fall time, running from a 40V input. The complete IC, including pads, takes up 4mm2 in a 0.35?m 50V CMOS process.

HØyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2007-01-01

194

A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells  

Energy Technology Data Exchange (ETDEWEB)

A highly efficient DC to DC converter has been developed for low-voltage high-current solid oxide fuel cells. The newly developed 'V6' converter resembles what has been done in internal combustion engine that split into multiple cylinders to increase the output capacity without having to increase individual cell size and to smooth out the torque with interleaving operation. The development was started with topology overview to ensure that all the DC to DC converter circuits were included in the study. Efficiency models for different circuit topologies were established, and computer simulations were performed to determine the best candidate converter circuit. Through design optimization including topology selection, device selection, magnetic component design, thermal design, and digital controller design, a bench prototype rated 5-kW, with 20 to 50V input and 200/400V output was fabricated and tested. Efficiency goal of 97% was proven achievable through hardware experiment. This DC to DC converter was then modified in the later stage to converter 35 to 63 V input and 13.8 V output for automotive charging applications. The complete prototype was tested at Delphi with their solid oxide fuel cell test stand to verify the performance of the modified DC to DC converter. The output was tested up to 3-kW level, and the efficiency exceeded 97.5%. Multiple-phase interleaving operation design was proved to be reliable and ripple free at the output, which is desirable for the battery charging. Overall this is a very successful collaboration project between the SECA Core Technology Team and Industrial Team.

Jason Lai

2009-03-03

195

Accurate Sliding-Mode Control System Modeling for Buck Converters  

DEFF Research Database (Denmark)

This paper shows that classical sliding mode theory fails to correctly predict the output impedance of the highly useful sliding mode PID compensated buck converter. The reason for this is identified as the assumption of the sliding variable being held at zero during sliding mode, effectively modeling the hysteretic comparator as an infinite gain. Correct prediction of output impedance is shown to be enabled by the use of a more elaborate, finite-gain model of the hysteretic comparator, which takes the effects of time delay and finite switching frequency into account. The demonstrated modeling approach also predicts the self-oscillating switching action of the sliding-mode control system correctly. Analytical findings are verified by simulation as well as experimentally in a 10-30V/3A buck converter.

HØyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2007-01-01

196

Soft Computing Module of High Step-Up DC–DC Converter for PV Module using Simulink Environment  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Within the photovoltaic (PV) power-generation market, the  PV module has shown obvious growth. However, a high voltage gain converter is essential for the module’s grid connection through a dc–ac inverter. This paper proposes a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and the numerous turns-ratios of a coupled indu...

Vinoth Kumar, K.; Suresh Kumar, S.; Daison Stallon, S.

2012-01-01

197

Characterization of an integrated buck converter using infrared thermography  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study deals with new integrated systems for power electronics applications including wide-gap semiconductors. Integration of Silicon carbide (SiC) components provides for instance new perspectives with higher temperature operating points than conventional Silicon (Si) semiconductors. The present work intends to study an integrated buck converter composed of a Silicon IGBT (Insulated-Gate Bipolar Transistor) and a Silicon carbide diode. By means of in...

Vivie?s, Noelle; Haussener, Marion; Welemane, He?le?ne; Trajin, Baptiste; Vidal, Paul-etienne

2014-01-01

198

On-chip SIDO buck converter with independent outputs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The portable electronics market is rapidly migrating towards more compact devices requiring multiple high-integrity high-efficiency voltage supplies for empowering the systems. This paper demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3 V. The main targets are low cross regulation between the two outputs to supply independent load current levels while maintaining desired output voltage values well within the accepta...

Marti?nez Garci?a, Herminio; Silva-marti?nez, Jose?

2013-01-01

199

Soft Computing Module of High Step-Up DC–DC Converter for PV Module using Simulink Environment  

Directory of Open Access Journals (Sweden)

Full Text Available Within the photovoltaic (PV power-generation market, the  PV module has shown obvious growth. However, a high voltage gain converter is essential for the module’s grid connection through a dc–ac inverter. This paper proposes a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and the numerous turns-ratios of a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the leakage inductor energy of the coupled inductor is efficiently recycled to the load. These features explain the module’s high-efficiency performance. The detailed operating principles and steady-state analyses of continuous, discontinuous, and boundary conduction modes are described. A 15V input voltage, 200V output voltage, and 100W output power prototype circuit of the proposed converter has been implemented; its maximum efficiency is up to 95.3% and full-load efficiency is 92.3%.

K. Vinoth Kumar

2012-12-01

200

A NEW GENERATION VLSI APPROACH FOR THE PWM CONTROL OF AN INTEGRATED FOUR-PORT DC-DC CONVERTER  

Directory of Open Access Journals (Sweden)

Full Text Available In the recent years, the increase in the petroleum prices, the rapid run out tendency of fossil fuel reserves and their unavoidable harmful effects and political instabilities in the regions of energy sources have been accelerated the studies on the renewable energy systems. Although various renewable energy power generations are in practice today, the most popular is using photovoltaic (PV arrays and wind generators. Since PV and wind sources can meet the required demand but either source alone provides an intermittent supply and energy storage is needed to deliver a reliable supply. However these two sources complement each other. A combined plant (hybrid therefore has higher availability than either individual source and so needs less storage capacity. This paper proposes a novel converter topology that interfaces four power ports: two sources (PVand wind source, one bidirectional storage port, and one isolated load port. Power electronic converter is needed to interface and concurrently control multiple renewable energy sources with the load along with energy storage in stand-alone or grid-connected residential, commercial and automobile applications. The power electronic interface also contains some level of monitoring and control functionality to ensure that the distributed energy system can operate as required. In the proposed scheme, a unique VLSI chip called Digital Signal Controller (DSC is used to implement the controller operation which has the features of both microcontroller and digital signal processor (DSP. In this work, dsPIC30F2010 DSC chip is used to program the phase shift angles and generate the PWM pulses for the converter switches. The results of proposed system are recorded and analyzed. The experimental results have verified the proposed scheme of PWM control. The proposed topology and control is particularly relevant to battery-backed power systems having multiple renewable sources.

SANGAMESH SAKRI

2012-12-01

 
 
 
 
201

A high voltage DC-DC converter driving a Dielectric Electro Active Polymer actuator for wind turbine flaps  

DEFF Research Database (Denmark)

The Dielectric Electro Active Polymer (DEAP) material is a very thin (~80 ?m) silicone elastomer film with a compliant metallic electrode layer on both sides. The DEAP is fundamentally a capacitor that is capable of very high strain. The property that the polymer changes its shape, as a result of the electrostatic forces generated by an applied voltage, can be used in actuators, for instance to adapt the trailing edges of wind turbine blades, for maximum efficiency and increased energy output. Conventional actuator technologies have not proven feasible solutions for driving the wind turbine flaps. With the DEAP based high power actuator, it is expected to make a reliable and light solution with superior controllability. The current DEAP technology requires high DC voltage in the range of kV to fully utilize the DEAP material as an actuator. In this paper we propose a flyback converter topology to obtain high voltage at low current, for driving the DEAP actuator. Simulation and experimental results for uni-directional flyback converter topology are shown.

Thummala, Prasanth; Zhang, Zhe

2012-01-01

202

Analysis and Design of Multi Input Dc–Dc Converter for Integrated Wind PV Cell Renewable Energy Generated System  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this paper is to propose amulti-input power converter for the hybrid system in order tosimplify the power system and reduce the cost. The proposedconverter interfaces two unidirectional input ports and abidirectional port for storage element in a unified structure. Italso utilizes four power switches that are controlled independentlywith four different duty ratios. The renewable power systemhybridizes PV and Wind as main source & Battery Power forbackup energy source. Three different power operation modes aredefined for the converter based on utilization state of the battery asfollows: 1 An operation type wherein power is delivered to loadfrom hybrid renewable energy sources; 2A single type whereinonly one renewable energy source supplies power to the load withbattery discharging; 3 An operation type wherein power isdelivered to load from renewable sources along with batterycharging. A simple and cost effective control with DC-DCconverter is used for maximum power point tracking (MPPT andhence maximum power is extracted from the source .Theintegration of the hybrid renewable power system is implementedand simulated using MATLAB/SIMULINK.

S. Ramya

2012-11-01

203

A Novel Over-Current Protection Technique Applied to Peak-Current Type DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available The change of the over-current protection point of the power switches, caused by slope compensation, is analyzed in detail. It is discovered that the peak current protecting value increases as the duty cycle decreases. As a result, the safety operation of the switches is damaged greatly. A novel solution to improve over-current protection with constant peak current limitation is proposed by inducing synchronous slope compensation into the current limit function instead of the original constant voltage. The design principle and method of the protection circuit based on a UC3846 PWM controller for the interleaved dual-forward converter is presented. Experimental results are given to verify the analysis.

Yan Xing

2010-06-01

204

Battery Management System—Balancing Modularization Based on a Single Switched Capacitor and Bi-Directional DC/DC Converter with the Auxiliary Battery  

Directory of Open Access Journals (Sweden)

Full Text Available Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small as possible. Without an appropriate balancing system, the individual cell voltages will differ over time and battery system capacity will decrease quickly. These issues will limit the electric range of the electric vehicle (EV and some cells will undergo higher stress, whereby the cycle life of these cells will be shorter. Quite a lot of cell balancing/equalization topologies have been previously proposed. These balancing topologies can be categorized into passive and active balancing. Active topologies are categorized according to the active element used for storing the energy such as capacitor and/or inductive component as well as controlling switches or converters. This paper proposes an intelligent battery management system (BMS including a battery pack charging and discharging control with a battery pack thermal management system. The BMS user input/output interfacing. The battery balancing system is based on battery pack modularization architecture. The proposed modularized balancing system has different equalization systems that operate inside and outside the modules. Innovative single switched capacitor (SSC control strategy is proposed to balance between the battery cells in the module (inside module balancing, IMB. Novel utilization of isolated bidirectional DC/DC converter (IBC is proposed to balance between the modules with the aid of the EV auxiliary battery (AB. Finally an experimental step-up has been implemented for the validation of the proposed balancing system.

Mohamed Daowd

2014-04-01

205

Stability Aspects in One-Cycle Controlled Buck Converters  

Directory of Open Access Journals (Sweden)

Full Text Available The paper aims to investigate issues related to one cycle controlled buck converters stability, in the situation when the integration capacitor discharging is performed through a non-zero value resistor, as it happens in practice. It is known that in this case the exponential discharge makes capacitor voltage theoretically never reach zero. Under these conditions, instability phenomena are expected when the discharge time is short, that is at high duty cycles. The stability condition is analytically derived with respect to the control voltage. It is shown that instability occurs with period doubling leading to a half switching frequency subharmonic. Computer simulations confirm the validity of theoretical considerations.

GURBINA, M.

2014-02-01

206

Integrated design & control of a buck boost converter  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english This paper presents the integrated design and control of a buck boost converter (BBC). In the proposed methodology the design tool provides simultaneously the controller tuning and BBC design parameters in such a way that some closed-loop pre-specified static and dynamic behavior is obtained. This a [...] pproach contrasts with the traditional methodology, where the design of BBC is performed without taking into account its dynamical behavior. An optimization procedure is used to obtain the electronic components of the BBC and the tuning parameters of the controller, minimizing an objective function that considers the set of performance specifications. Although the methodology can be applied to any converter and any control strategy, in this particular case an ideal BBC and a Sliding Model Control (SMC) strategy are used. Some simulation results show the advantages and principally the flexibility that can be obtained with this approach.

Martin J. Pomar, Garcia; Julio E., Normey-Rico; Gloria, Gutierrez; César de, Prada.

2009-09-01

207

A 1500 mA, 10 MHz on-time controlled buck converter with ripple compensation and efficiency optimization  

Science.gov (United States)

A 1500 mA, 10 MHz self-adaptive on-time (SOT) controlled buck DC—DC converter is presented. Both a low-cost ripple compensation scheme (RCS) and a self-adaptive on-time generator (SAOTG) are proposed to solve the system stability and frequency variation problem. Meanwhile a self-adaptive power transistor sizing (SAPTS) technique is used to optimize the efficiency especially with a heavy load. The circuit is implemented in a 2P4M 0.35 ?m CMOS process. A small external inductor of 0.47 ?H and a capacitor of 4.7 ?F are used to lower the cost of the converter and keep the output ripple to less than 10 mV. The measurement results show that the overshoot of the load transient response is 8 mV @ 200 mA step and the dynamic voltage scaling (DVS) performance is a rise of 16 ?s/V and a fall of 20 ?s/V. With a SAPTS technique and PFM control, the efficiency is maintained at more than 81% for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%.

Jiale, Yu; Danzhu, Lü; Zhiliang, Hong

2012-01-01

208

A 1500 mA, 10 MHz on-time controlled buck converter with ripple compensation and efficiency optimization  

International Nuclear Information System (INIS)

A 1500 mA, 10 MHz self-adaptive on-time (SOT) controlled buck DC—DC converter is presented. Both a low-cost ripple compensation scheme (RCS) and a self-adaptive on-time generator (SAOTG) are proposed to solve the system stability and frequency variation problem. Meanwhile a self-adaptive power transistor sizing (SAPTS) technique is used to optimize the efficiency especially with a heavy load. The circuit is implemented in a 2P4M 0.35 ?m CMOS process. A small external inductor of 0.47 ?H and a capacitor of 4.7 ?F are used to lower the cost of the converter and keep the output ripple to less than 10 mV. The measurement results show that the overshoot of the load transient response is 8 mV at 200 mA step and the dynamic voltage scaling (DVS) performance is a rise of 16 ?s/V and a fall of 20 ?s/V. With a SAPTS technique and PFM control, the efficiency is maintained at more than 81% for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%. (semiconductor integrated circuits)

209

ASDTIC control and standardized interface circuits applied to buck, parallel and buck-boost dc to dc power converters  

Science.gov (United States)

Versatile standardized pulse modulation nondissipatively regulated control signal processing circuits were applied to three most commonly used dc to dc power converter configurations: (1) the series switching buck-regulator, (2) the pulse modulated parallel inverter, and (3) the buck-boost converter. The unique control concept and the commonality of control functions for all switching regulators have resulted in improved static and dynamic performance and control circuit standardization. New power-circuit technology was also applied to enhance reliability and to achieve optimum weight and efficiency.

Schoenfeld, A. D.; Yu, Y.

1973-01-01

210

Research of an Efficient LED Lighting Driver Based on Boost-Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Boost-Buck converter is widely used in LED lighting drivers. In this paper, Boost-Buck main circuit related characteristics are firstly discussed, and then a new Boost-Buck high power efficient double loop control strategy is built by adopting error amplifier and integrator control method. It is demonstrated that the new system has many advantages such as high efficiency, fast response, strong anti-interference, good stability after analyses and simulations of its wo...

Renbo Xu; Yongzhi Li; Lixin Zhong; Jiaming Liu

2014-01-01

211

Nonlinear program based optimization of boost and buck-boost converter designs  

Science.gov (United States)

The facility of an Augmented Lagrangian (ALAG) multiplier based nonlinear programming technique is demonstrated for minimum-weight design optimizations of boost and buck-boost power converters. Certain important features of ALAG are presented in the framework of a comprehensive design example for buck-boost power converter design optimization. The study provides refreshing design insight of power converters and presents such information as weight and loss profiles of various semiconductor components and magnetics as a function of the switching frequency.

Rahman, S.; Lee, F. C.

1981-01-01

212

Design Of Converter For Low Power Photovoltaic Conversion System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The solar energy conversion system is an alternative for conventional power generating system. It has no running cost due to freely available and non polluting solar radiations. The voltage which is available from solar array is variable and to obtain a stable voltage from solar panels, DC-DC converters are required for constant power production. There are mainly three converters namely Buck, Boost and Buck-Boost converters which can be used for either increasing or decreasing the voltage. Th...

Swapnil Zadey, Subroto Dutt

2013-01-01

213

Milliwatt dc/dc Inverter  

Science.gov (United States)

Compact dc/dc inverter uses single integrated-circuit package containing six inverter gates that generate and amplify 100-kHz square-wave switching signal. Square-wave switching inverts 10-volt local power to isolated voltage at another desired level. Relatively high operating frequency reduces size of filter capacitors required, resulting in small package unit.

Mclyman, C. W.

1983-01-01

214

Automated design approaches for power electronics converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The design of dc-dc power converters is formulated as a multi-objective optimization problem, in which the objectives are to minimize the total converter mass and power loss. The design approach is demonstrated using buck converter modules as examples. The impacts of major converter components, including the energy storage inductor, output filter capacitor, semiconductor switching devices and associated heat sink are incorporated. To further alleviate the effect of large number of design para...

Wang, Shengyu

2010-01-01

215

Sliding-Mode Control Design of a Boost-Buck Switching Converter for AC Signal Generation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a sliding-mode control design of a boost???buck switching converter for a voltage step-up dc???ac conversion without the use of any transformer. This approach combines the step-up/step-down conversion ratio capability of the converter with the robustness properties of sliding-mode control. The proposed control strategy is based on the design of two slidingcontrol laws, one ensuring the control of a full-bridge buck converter for proper dc???ac conversion,...

Biel Sol??, Domingo; Guinjoan Gispert, Francisco; Fossas Colet, Enric; Chavarr??a Ro??, Javier

2004-01-01

216

Dual-Input Soft-Switched DC-DC Converter with Isolated Current-Fed Half-Bridge and Voltage-Fed Full-Bridge for Fuel Cell or Photovoltaic Systems  

DEFF Research Database (Denmark)

This paper introduces a new zero-voltage-switching (ZVS) isolated DC-DC converter with two input ports which can be utilized in hybrid energy systems, for instance, in a fuel cell and super-capacitor system. By fully using two high frequency transformers, the proposed converter can effectively integrate a current-fed boost half-bridge (BHB) and a full-bridge (FB) into one equivalent circuit configuration which has dual-input ability and additionally it can reduce the number of the power devices. With the phase-shift control, it can achieve zero-voltage switching turn-on of active switches and zero-current switching (ZCS) turn-off of diodes leading to negligible reverse recovery loss. Voltage conversion ratio is higher compared to the conventional boost converter owing to the BHB circuit and the corresponding control. Finally, a 25~50 V input, 300~400 V output prototype with a 600 W nominal power rating are built up and tested to demonstrate the effectiveness of the proposed converter topology.

Zhang, Zhe; Thomsen, Ole Cornelius

2013-01-01

217

Simulation and Implementation a Non-Isolated Buck Converter at ZCS Condition  

Directory of Open Access Journals (Sweden)

Full Text Available A new soft-switching resonant inverting-buck converter with high efficiency is presented. The proposed converter steps down and inverts the input voltage. The zero-current-switching (ZCS technique is employed to reduce switching losses and Electromagnetic Interferences (EMI. An LLC resonant network is utilized to provide soft-switching conditions for all semiconductor devices. Experimental results verify the integrity of the proposed converter operation and the presented theoretical analysis.

Nahid Hematian

2013-10-01

218

Interleaved Buck Converter with Variable Number of Active Phases and a Predictive Current Sharing Scheme  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The efficiency of an interleaved Buck converter is typically low at light load conditions because of the switching losses in each of the switching stages. Improvements in the converter efficiency can be achieved by dynamically changing the number of active phases depending on the load current. This paper addresses the issues related to the transient response of the converter when the number of active phases is changed by a digital control scheme. The problem arises bec...

Jakobsen, L. T.; Garci?a Sua?rez, Oscar; Oliver Rami?rez, Jesu?s Angel; Alou Cervera, Pedro; Cobos Ma?rquez, Jose? Antonio; Andersen, M. A. E.

2008-01-01

219

Transfer function modeling and analysis of the open-loop Buck converter using the fractional calculus  

International Nuclear Information System (INIS)

Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus, the transfer function modeling and analysis of the open-loop Buck converter in a continuous conduction mode (CCM) operation are carried out in this paper. The fractional order small signal model and the corresponding equivalent circuit of the open-loop Buck converter in a CCM operation are presented. The transfer functions from the input voltage to the output voltage, from the input voltage to the inductor current, from the duty cycle to the output voltage, from the duty cycle to the inductor current, and the output impedance of the open-loop Buck converter in CCM operation are derived, and their bode diagrams and step responses are calculated, respectively. It is found that all the derived fractional order transfer functions of the system are influenced by the fractional orders of the inductor and the capacitor. Finally, the realization of the fractional order inductor and the fractional order capacitor is designed, and the corresponding PSIM circuit simulation results of the open-loop Buck converter in CCM operation are given to confirm the correctness of the derivations and the theoretical analysis

220

Comparison of 3 self-starting step-up DC:DC converter topologies for harvesting energy from low-voltage and low-power microbial fuel cells  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper describes and evaluates 3 original step-up converter architectures able to harvest energy from low-voltage and low-power generators. Design and sizing are made according to specifications issued from the stringent characteristics of microbial fuel cells. The maximum harvested power is 10mW under input voltage Vin=0.3V (33mA input current). The considered converters include self-oscillating circuits for autonomous operation. The 2 first topologies are respectively adapted from boost...

Degrenne, Nicolas; Allard, Bruno; Buret, Franc?ois; Morel, Florent; Adami, Salah-eddine; Labrousse, Denis

2011-01-01

 
 
 
 
221

Soft switching buck-boost converter for photovoltaic power generation; Taiyoko hatsuden no tame no soft switching shokoatsu converter  

Energy Technology Data Exchange (ETDEWEB)

A soft switching method with small switching loss was proposed for the purpose of increasing the efficiency of a DC-DC boost converter which converted a DC current generated by solar cells to a variable DC current. Existing current converters are supplemented by using a snubber circuit around the switch so as to protect the switch by a hard switching action. However, with an increase of the output current, snubber loss is increased, reducing the efficiency. In order to solve this problem, the partial resonant switch method was applied to the converter; with this method of partially forming a resonant circuit only at the time of turning on/off of the switch, the switching loss was reduced through the soft switching, thereby making the proposed converter operate with high efficiency. Moreover, the resonant element of the partial resonant circuit using a snubber condenser, the energy accumulated in the condenser was regenerated on the power supply side without loss of snubber. With the regenerated energy, the proposed converter was provided with a smaller ratio of switching to use than the conventional converter. 4 refs., 7 figs., 1 tab.

Lee, H. [Kyungnam University (Korea, Republic of)

1996-10-27

222

Implementation of Buck-Boost Converter with Coupled Inductor for Photo-Voltaic System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The solar energy is a very interesting alternative on supplement the electrical system generation. In this paper, a photovoltaic based system is obtained from a boost cascaded with a buck converter along with Coupled inductor. Due to its novel operating modes, high efficiency can be achieved because there is only one switch operating at high frequency at a time, and the converter allows the use of power MOSFET and ultra-fast reverse recovery diode. This paper begins with theoretical analys...

Subbulakshmi, M. S.; Vanitha, D.

2014-01-01

223

Interleaved Buck Converter with Variable Number of Active Phases and a Predictive Current Sharing Scheme  

DEFF Research Database (Denmark)

The efficiency of an interleaved Buck converter is typically low at light load conditions because of the switching losses in each of the switching stages. Improvements in the converter efficiency can be achieved by dynamically changing the number of active phases depending on the load current. This paper addresses the issues related to the transient response of the converter when the number of active phases is changed by a digital control scheme. The problem arises because the current in the individual phases of the interleaved Buck converter will not be equal immediately after the controller has changed the number of active phases. This paper proposes a current equalisation scheme that adjusts the duty cycle of each phase in a manner that ensures equal average inductor current in all active phases in one or two PWM periods. The current equalisation scheme relies on the measurement of the output current and the knowledge of a few converter parameters and it does not require a measurement of the current in each phase. A digital PWM modulator has been designed that allows the current equalisation scheme to work. Simulations and measurements for a four phase interleaved Buck converter are presented and shows that the predictive current equalisation scheme can equalise the phase currents in a single PWM period.

Jakobsen, Lars TØnnes; Garcia, O.

2008-01-01

224

Square wave series voltage compensator with high frequency DC-DC converter; Compensador serie de tensao em onda quadrada com conversor CC-CC de alta frequencia  

Energy Technology Data Exchange (ETDEWEB)

The square wave series voltage compensator is an equipment used to mitigate voltage sags. In the case of occurrence of a voltage disturbance, the compensator acts generating a square wave voltage to supply the missing voltage. The energy inserted for the compensation is taken from the electrical grid, by a linear source. The purpose of this paper is to present a switching shunt converter instead of a linear one, with the same output parameters in order to increase the power density. This efficiency is demonstrated by simulations. (author)

Moreira, Angelo Roberto Rodrigues Resende; Caetano, William Douglas; Pires, Igor Amariz; Silva, Arlete Vieira da [Centro Universitario de Belo Horizonte (UnBH), MG (Brazil)], e-mails: angelogalo2005@hotmail.com, wdouglasbh@gmail.com, igor_amariz@yahoo.com.br, arlete.silva@prof.unibh.br

2011-07-01

225

Zero-Voltage and Zero-Current Switching Buck-Boost Converter for PV Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A ZVS and ZCS buck boost converter is presented for PV panel applications. The salient points are that all the switching devices are under zero-current switching during turn-on and zero-voltage switching during turn-off. The active switches in the converter undergo zero-capacitive turn-on losses unlike switches in other soft-switched topologies. The switches do not experience any over voltage/over current stress proportional to load as in resonant converters. This soft-switching technique ...

Prem, Athulya P.; Sudhin Govind; Ravi, Chinnu P.

2014-01-01

226

Modelling and Simulation of Closed Loop Controlled Buck Converter Fed Pmbldc Drive System  

Directory of Open Access Journals (Sweden)

Full Text Available Permanent Magnet Brushless DC Motor (PMBLDC is one of the best electrical drives that has increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. This makes the interest of modeling an ideal PMBLDC motor and it’s associated Drive System in simple and lucid manner. In this paper the drive system is proposed with a buck converter topology. It has the advantages of reduced switching losses, low inductor power loss, reduced ripple by using a pi-filter, which in turn makes the DC link voltage to be stable. The modeling and simulation of the PMBLDC motor is done using the software package MATLAB/SIMULINK. The operation principle of the buck converter is analyzed and the simulation results are presented in this paper to verify the theoretical analysis.

R. Dhanasekaran

2011-04-01

227

Filter based non-invasive control of chaos in Buck converter  

International Nuclear Information System (INIS)

A non-invasive method for controlling chaos in the voltage-mode Buck converter is proposed by using a hybrid active filter based feedback controller in this Letter. The harmonic balance method is applied to obtaining the bifurcation-point equations of the controlled system. Hence, a stability-boundary diagram is constructed, through which the control parameters are chosen correctly. The results of simulation and experiment are given after all

228

A Positive Buck Boost Converter with Mode Select Circuit and Feed Forward Techniques Using Fuzzy Logic Controller  

Directory of Open Access Journals (Sweden)

Full Text Available The portable devices development of semiconductor manufacturing technology, conversion efficiency, power consumption, and the size of devices have become the most important design criteria of switching power converters. For portable applications better conveniences extension of battery life and improves the conversion efficiency of power converters .It is essential to develop accurate switching power converters, which can reduce more wasted power energy. The proposed topology can achieve faster transient responses when the supply voltages are changed for the converter by making use of the feed forward network .With mode select circuit the conduction & switching losses are reduced the positive buck–boost converter operate in buck, buck–boost, or boost converter. By adding feed-forward techniques, the proposed converter can improve transient response when the supply voltages are changed. The designing, modeling & experimental results were verified in MATLAB/ Simulink. The fuzzy logic controller is used as controller.

Latha. S. C

2014-11-01

229

The High Power factor Buck-boost PWM Converter of Soft Switching  

Energy Technology Data Exchange (ETDEWEB)

Power conversion system must be increased switching frequency in order to achieve a small size, a light weight and a low noise. However, the switches of converter are subjected to high switching power losses and switching stresses. As a result of those, the power system brings on a low efficiency. In this paper, the authors propose a DC-DC boost converter of high power by partial resonant switch method (PRSM). The switching devices in a proposed circuit are operated with soft switching and the control technique of those is simplified for switch to drive in constant duty cycle. The partial resonant circuit makes use of a inductor using step up and a condenser of loss-less snubber. Also the circuit has a merit which is taken to increase of efficiency, as it makes to a regeneration at input source of accumulated energy in snubber condenser without loss of snubber in conventional circuit. The result is that the switching loss is very low and the efficiency of system is high. The proposed converter is deemed he most suitable for high power applications where the power switching devices are used. (author). 11 refs., 8 figs., 1 tab.

Park, K.W.; Suh, K.Y.; Lee, S.H.; Lee, H.W. [KyungNam University (Korea, Republic of); Cho, P.J. [Cho Sun Beer Co. (Korea, Republic of)

1997-04-01

230

Zero-Voltage and Zero-Current Switching Buck-Boost Converter for PV Applications  

Directory of Open Access Journals (Sweden)

Full Text Available A ZVS and ZCS buck boost converter is presented for PV panel applications. The salient points are that all the switching devices are under zero-current switching during turn-on and zero-voltage switching during turn-off. The active switches in the converter undergo zero-capacitive turn-on losses unlike switches in other soft-switched topologies. The switches do not experience any over voltage/over current stress proportional to load as in resonant converters. This soft-switching technique can also be applied to other classical switched mode power converters. A detailed analysis of the converter under steady state is discussed and simulation results obtained are presented.

Athulya P Prem

2014-12-01

231

Design Of Converter For Low Power Photovoltaic Conversion System  

Directory of Open Access Journals (Sweden)

Full Text Available The solar energy conversion system is an alternative for conventional power generating system. It has no running cost due to freely available and non polluting solar radiations. The voltage which is available from solar array is variable and to obtain a stable voltage from solar panels, DC-DC converters are required for constant power production. There are mainly three converters namely Buck, Boost and Buck-Boost converters which can be used for either increasing or decreasing the voltage. This paper presents mobile charging circuit with a PV source. The circuit structure of the proposed system adopts buck converter combined PWM MPPT technique. In this research, buck converter is used as a charger for charging mobile battery. The input voltage can typically change from (12V initially, down to (5V, and provide a regulated voltage within the range of the 4.5V required for the charging of mobile batteries.

SWAPNIL ZADEY, SUBROTO DUTT

2013-06-01

232

The Series Connected Buck Boost Regulator Concept for High Efficiency Light Weight DC Voltage Regulation  

Science.gov (United States)

Improvements in the efficiency and size of DC-DC converters have resulted from advances in components, primarily semiconductors, and improved topologies. One topology, which has shown very high potential in limited applications, is the Series Connected Boost Unit (SCBU), wherein a small DC-DC converter output is connected in series with the input bus to provide an output voltage equal to or greater than the input voltage. Since the DC-DC converter switches only a fraction of the power throughput, the overall system efficiency is very high. But this technique is limited to applications where the output is always greater than the input. The Series Connected Buck Boost Regulator (SCBBR) concept extends partial power processing technique used in the SCBU to operation when the desired output voltage is higher or lower than the input voltage, and the implementation described can even operate as a conventional buck converter to operate at very low output to input voltage ratios. This paper describes the operation and performance of an SCBBR configured as a bus voltage regulator providing 50 percent voltage regulation range, bus switching, and overload limiting, operating above 98 percent efficiency. The technique does not provide input-output isolation.

Birchenough, Arthur G.

2003-01-01

233

Modeling and dynamics analysis of the fractional-order Buck—Boost converter in continuous conduction mode  

Science.gov (United States)

In this paper, the fractional-order mathematical model and the fractional-order state-space averaging model of the Buck—Boost converter in continuous conduction mode (CCM) are established based on the fractional calculus and the Adomian decomposition method. Some dynamical properties of the current-mode controlled fractional-order Buck—Boost converter are analysed. The simulation is accomplished by using SIMULINK. Numerical simulations are presented to verify the analytical results and we find that bifurcation points will be moved backward as ? and ? vary. At the same time, the simulation results show that the converter goes through different routes to chaos.

Yang, Ning-Ning; Liu, Chong-Xin; Wu, Chao-Jun

2012-08-01

234

Modeling and dynamics analysis of the fractional-order Buck—Boost converter in continuous conduction mode  

International Nuclear Information System (INIS)

In this paper, the fractional-order mathematical model and the fractional-order state-space averaging model of the Buck—Boost converter in continuous conduction mode (CCM) are established based on the fractional calculus and the Adomian decomposition method. Some dynamical properties of the current-mode controlled fractional-order Buck—Boost converter are analysed. The simulation is accomplished by using SIMULINK. Numerical simulations are presented to verify the analytical results and we find that bifurcation points will be moved backward as ? and ? vary. At the same time, the simulation results show that the converter goes through different routes to chaos. (general)

235

A High Step-Down Interleaved Buck Converter with Active-Clamp Circuits for Wind Turbines  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a high step-down interleaved buck coupled-inductor converter (IBCC) with active-clamp circuits for wind energy conversion has been studied. In high step-down voltage applications, an IBCC can extend duty ratio and reduce voltage stresses on active switches. In order to reduce switching losses of active switches to improve conversion efficiency, a IBCC with soft-switching techniques is usually required. Compared with passive-clamp circuits, the IBCC with active-clamp circuits ha...

Chih-Lung Shen; Cheng-Tao Tsai

2012-01-01

236

Reduce Energy Losses and THD in Buck Converter Using Control Algorithm  

Directory of Open Access Journals (Sweden)

Full Text Available The paper will focus on modeling, analysis, and design and simulation buck converter architecture. This architecture is used for automotive dual power system to reduce filters, dynamic response and power. The converter is designed in CCM (continuous conduction mode. The voltage mode control strategy is proposed by using pulse width modulation (PWM with a proportional-integralderivative (PID. The effectiveness of the step down converter is verified through simulation results using control oriented simulator like MATLAB/Simulink tools.The proposed circuits operate at constant frequency and are regulated by conventional pulse width modulation (PWM using dedicated PWM and PID control techniques. The circuit operation, mathematical analysis, designs and simulation results for continuous current mode (CCM operation are mentioned in this paper.

Vipul C. Rajyaguru, Keerti S.Vashishtha, K. C. Dave

2012-04-01

237

Design and Analysis of PI like Fuzzy Logic Controlled Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a novel design of Proportional and Integral (PI - like Fuzzy Logic Controller (FLC for Buck converters that integrates linear control techniques with Fuzzy Logic .The design procedure allows the small signal model of the converter and linear control design techniques to be used in the initial stages of FLC design. This simplifies the small signal design and stability assessment of the FLC.By exploiting the Fuzzy Logic structure of the controller, heuristic knowledge is incorporated in the design, which results in a nonlinear controller with improved Performance over linear PI controllers. The major advantage of the proposed design method for FLC is that compared to other methods is trial and error effort in the design is greatly reduced. MATLAB/SIMULINK is used for implementation and results shows the performance of the converter.

M.SIVA RAMA KRISHNA

2013-06-01

238

Performance Comparison of Various Control Algorithms for an Asynchronous Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available The control of power electronic circuits is a challenging field of research due to the requirements imposed by the applications. A controller design for a Buck converter which steps down a given dc value to a desired regulated dc value is the system taken into consideration in this study. The controller designed for Buck converter has to control rise time, peak overshoot, settling time, bandwidth which are affected by the load and line variations. Quarter Amplitude Decay (QAD, Internal Model Control (IMC and Pole placement techniques are used to obtain the parameters of the PID controller. The performances of these tuning procedures are evaluated and the comparison is tabulated. It is found that the controller tuned by pole placement method gives less rise time and settling time with negligible overshoot. But transfer function of pole-placement base controller is quite complex and has high number coefficients which is difficult to realize in real time systems. QAD based PID controller has less rise time and settling time but it has peak over shoot which will produce voltage spikes in real time systems. Hence an IMC based PID controller which has acceptable rise time and settling time with no peak overshoot is realized in real form by using operational amplifiers. The performance is evaluated and tabulated under varying load and reference voltage conditions.

S. AugustiLindiya

2014-01-01

239

Steady-state analysis of dead-time effect on bidirectional buck converters  

DEFF Research Database (Denmark)

Half-bridge inverters, full-bridge inverters and bidirectional buck converters share a common topological structure, in which two switches and two diodes are present. In such a topology, a dead time between the two signals controlling the switches is inserted. This influences the relationship between output voltage, input voltage and duty cycle as a function of the output current. In the literature, the dead-time effect has been studied in relation with inverters, active filters, voltage regulated modules and high-precision power amplifiers, and dead-time compensation techniques have been proposed. However, the measurement of the current is normally required for all dead-time compensation strategies, which can be a problem when the current approaches or crosses zero. In this paper, the operation of a bidirectional buck converter in the region around zero current has been analytically analyzed. It has been shown that in a region around zero there is no dead-time effect. The analytical expression of the bordersbetween the areas where the dead-time effect is positive, zero or negative has been given. Moreover it has been shown that between these three areas, there are four other transitional areas. The analytical analysis has been confirmed by simulation and experimental results.

Bidoggia, Benoit; Maheshwari, Ram Krishan

2012-01-01

240

A Tapped-Inductor Buck-Boost Converter for a Dielectric ElectroActive Polymer Generator  

DEFF Research Database (Denmark)

Energy harvesting applications based on Dielectric ElectroActive Polymer (DEAP) generators have been in the spotlight in recent years after the latter ones’ documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter. In addition, the effective operational range of the converter is usually limited by the lack of commercially-available, high-efficient, high-voltage, low-power semiconductor devices. In this paper, a high-efficient bidirectional tapped-inductor buck-boost converter, addressing high step-up and high step-down voltage conversion ratios, is proposed for energy harvesting applications based on DEAP generators. The high-side switch of the converter is replaced by a string of three non-matched, non-thermally-coupled, off-the-shelf MOSFETs, extending its effective operational range. Experiments conducted on a standalone DEAP generator validate the applicability of the proposed converter by demonstrating energy harvesting of 0.42 J, at 0.75 Hz and 60 % delta-strain, characterized by a world-first; energy density equal to 2 J per kg of active material.

Dimopoulos, Emmanouil; Munk-Nielsen, Stig

2014-01-01

 
 
 
 
241

Active pre-filters for dc/dc Boost regulators / Pre-filtros activos para reguladores dc/dc elevadores  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: English Abstract in spanish Este artículo propone un pre-filtro activo para mitigar los armónicos de corriente generados por reguladores elevadores clásicos, los cuales producen rizados de corriente proporcionales al ciclo de trabajo. Por tanto, altos voltajes de salida, i.e., altos factores de transformación de voltaje, produ [...] cen armónicos de corriente que se deben filtrar para evitar daños o pérdidas de potencia en la fuente. Tradicionalmente, estas componentes se filtran usando condensadores electrolíticos, lo que introducen problemas de confiabilidad debido a su alta taza de falla. En contraste, la solución propuesta usa un convertidor dc/dc, basado en la conexión paralela de celdas canónicas Boost, para filtrar el rizado de corriente generado por el regulador Boost, lo que mejora la confiabilidad del sistema. Esta solución, además, incrementa la eficiencia total y el factor de transformación de voltaje. Finalmente, la solución se valida usando simulaciones y resultados experimentales. Abstract in english This paper proposes an active pre-filter to mitigate the current harmonics generated by classical dc/dc Boost regulators, which generate current ripples proportional to the duty cycle. Therefore, high output voltage conditions, i.e., high voltage conversion ratios, produce high current harmonics tha [...] t must be filtered to avoid damage or source losses. Traditionally, these current components are filtered using electrolytic capacitors, which introduce reliability problems because of their high failure rate. The solution introduced in this paper instead uses a dc/dc converter based on the parallel connection of the Boost canonical cells to filter the current ripples generated by the Boost regulator, improving the system reliability. This solution provides the additional benefits of improving the overall efficiency and the voltage conversion ratio. Finally, the solution is validated with simulations and experimental results.

C. A, Ramos-Paja; R, Giral; C, Carrejo.

2014-08-01

242

Mode shift and stability control of a current mode controlled buck-boost converter operating in discontinuous conduction mode with ramp compensation  

International Nuclear Information System (INIS)

By establishing the discrete iterative mapping model of a current mode controlled buck-boost converter, this paper studies the mechanism of mode shift and stability control of the buck-boost converter operating in discontinuous conduction mode with a ramp compensation current. With the bifurcation diagram, Lyapunov exponent spectrum, time-domain waveform and parameter space map, the performance of the buck-boost converter circuit utilizing a compensating ramp current has been analysed. The obtained results indicate that the system trajectory is weakly chaotic and strongly intermittent under discontinuous conduction mode. By using ramp compensation, the buck-boost converter can shift from discontinuous conduction mode to continuous conduction mode, and effectively operates in the stable period-one region. (general)

243

MPPT Using Fuzzy Logic Control and Buck Converter for Photovoltaic System  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a fuzzy logic control (FLC is proposed to control the maximum power point tracking (MPPT for a photovoltaic (PV system. The proposed technique uses the fuzzy logic control to specify the size of incremental current in the current command of MPPT. As results indicated, the convergence time of maximum power point (MPP of the proposed algorithm is better than that of the conventional Perturb and Observation (P&O technique. The simulation results have been used to verify the effectiveness of the algorithm. The proposed method produces good efficiency with low switching loss. The nonlinearity and adaptiveness of fuzzy controller provided good performance under parameter variations such as solar irradiation. Tracking of the maximum power point (MPPT plays an important role in photovoltaic(PV power systems because they maximize the power output from a PV system for a given set of conditions, and therefore maximize they module efficiency. This work presents a fuzzy logic controller based MPPT algorithms using design of dc to dc new buck converter for photovoltaic applications. The introduction of fuzzy c

C.Thulasi Priya*1,

2014-05-01

244

Buck-boost converter for simultaneous semi-active vibration control and energy harvesting for electromagnetic regenerative shock absorber  

Science.gov (United States)

Regenerative semi-active suspensions can capture the previously dissipated vibration energy and convert it to usable electrical energy for powering on-board electronic devices, while achieve both the better ride comfort and improved road handling performance at the same time when certain control is applied. To achieve this objective, the power electronics interface circuit connecting the energy harvester and the electrical loads, which can perform simultaneous vibration control and energy harvesting function is in need. This paper utilized a buck-boost converter for simultaneous semi-active vibration control and energy harvesting with electromagnetic regenerative shock absorber, which utilizes a rotational generator to converter the vibration energy to electricity. It has been found that when the circuit works in discontinuous current mode (DCM), the ratio between the input voltage and current is only related to the duty cycle of the switch pulse width modulation signal. Using this property, the buck-boost converter can be used to perform semi-active vibration control by controlling the load connected between the terminals of the generator in the electromagnetic shock absorber. While performing the vibration control, the circuit always draw current from the shock absorber and the suspension remain dissipative, and the shock absorber takes no additional energy to perform the vibration control. The working principle and dynamics of the circuit has been analyzed and simulations were performed to validate the concept.

Li, Peng; Zhang, Chongxiao; Kim, Junyoung; Yu, Liangyao; Zuo, Lei

2014-04-01

245

Integrated module inverter using a zeta DC-DC converter with feedforward MPPT (Maximum Power Point Tracking) control; Inversor modulo integrado utilizando um conversor CC-CC zeta com controle MPPT feedforward  

Energy Technology Data Exchange (ETDEWEB)

This work presents the study and development of a processing power system that could be used in the connection of renewable energy sources to commercial power grid. The system consists of a ZETA converter associated with a bridge inverter operating at low frequency. The Zeta converter, operating in discontinuous conduction mode (DCM), plays the main role in this arrangement, producing a rectified sinusoidal current waveform synchronized with the electric grid. The function of the full-bridge inverter, connected in cascade with the Zeta converter, is to reverse every 180 deg the current generated by the Zeta converter. Initially it presents the analysis of the Zeta converter operating in DCM, as well as a design criterion. Following by the control strategy and the experimental results for the proposed system are presented and discussed. (author)

Lopez, Henrique Fioravanti Miguel

2009-08-15

246

Efficient Design to Meet High Power Density Applications Using DC-DC Energy Conversion  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In order to meet higher power applications in power electronics system this proposed with implantation using DC-DC energy conversion with resonant converter. Present generation there is a huge amount of markets has increased the demand for high efficiency and high power density applications. But Conventional adopted pulse width modulation includes small weight, low power, low efficiency, due to high switching frequencies in diodes. The proposed system implements a half-bridge ...

Ashok, L.

2014-01-01

247

Adaptive Fuzzy Control of a Fuel Cell/DC-DC Convertor System  

Directory of Open Access Journals (Sweden)

Full Text Available Maintaining a fuel cell system in a correct operating status requires good system control. An adaptive fuzzy control scheme is proposed in this study for the fuel cell/DC-DC converter system to realize constant voltage output under different loads. PID controller and fuzzy controller are used to compare with the proposed adaptive fuzzy controller. Simulation results show that the adaptive fuzzy controller can provide attractive control effects such as faster response characteristic and better steady-state behavior.

Fan Li-Ping

2013-01-01

248

DC-DC Conversion Powering Schemes for the CMS Tracker Upgrade  

CERN Document Server

The CMS experiment foresees upgrades of its silicon pixel and strip detectors for the luminosity upgrade of the Large Hadron Collider (LHC), CERN. Due to an increase in the number of readout channels and higher complexity, larger currents will have to be provided to the detector. Since cable channels are difficult to access and space for cables is limited, this would lead to excessively large resistive power losses in the supply cables, which increase with the current squared. CMS has therefore chosen a novel powering scheme based on DC-DC converters, which allows power to be delivered at a higher voltage and consequently lower current. The development of low-mass, low-noise DC-DC converters for application in CMS is presented, including studies of switching noise, magnetic emissions and power efficiency as well as system tests with silicon strip and pixel modules. A scheme for the integration of DC-DC converters in the silicon pixel detector, currently foreseen to be exchanged around 2016, will be discussed.

Feld, Lutz; Klein, Katja; Merz, Jennifer; Sammet, Jan; Wlochal,Michael

2011-01-01

249

Analysis of Planar E+I and ER+I Transformers for Low-Voltage High-Current DC/DC Converters with Focus on Winding Losses and Leakage Inductance  

DEFF Research Database (Denmark)

In this paper an analysis of two planar transformers designed for high-current switching applications is presented. Typical converter application is represented by fuel and electrolyser cell converters. The transformer designs are based on E+I and ER+I planar cores while the analysis focuses on winding resistance and leakage inductances which represent the main concerns related to low-voltage high-current applications. The PCB winding design has a one to one turn ratio with no interleaving between primary and secondary windings. The main goal was to determine if ER planar core could provide a significant advantage in terms of winding losses compared to planar E cores. Results from finite element analysis highlight that low frequency winding resistance is lower for the ER core since it is dominated by the lower mean turn length however, as the AC-resistance becomes dominating the winding eddy current losses increases more in the ER core than in the E core design. Calculated and simulated leakage inductances for the analyzed cores do not show relevant differences. A laboratory prototype based on E64 planar core is used as reference. Laboratory measurements highlight that FEM analysis provides more realistic results when computing the winding AC-resistance.

Pittini, Riccardo; Zhang, Zhe

2012-01-01

250

A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system  

Science.gov (United States)

Interest on Dielectric ElectroActive Polymer (DEAP) generators has aroused among scientists in recent years, due to the former ones' documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter. On top of that, the shortage of commercially-available, high-efficient, high-voltage, low-power semiconductor devices limits the effective operational range of the power electronic converter. In this paper, a bidirectional tapped-inductor buck-boost converter is proposed, addressing high- efficient high step-up and high step-down voltage conversion ratios, for energy harvesting applications based on DEAP generators. The effective operational range of the converter is extended, by replacing its high-side switch with a string of three serialized MOSFETs, to accommodate the need for high-efficient high-voltage operation. Experiments conducted on a single DEAP generator - part of a quadruple DEAP generator energy harvesting system with all elements installed sequentially in the same circular disk with a 90° phase shift - validate the applicability of the proposed converter, demonstrating energy harvesting of 0.26 J, at 0.5 Hz and 60% delta- strain; characterized by an energy density of 1.25 J per kg of active material.

Dimopoulos, Emmanouil; Munk-Nielsen, Stig

2014-03-01

251

A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system  

DEFF Research Database (Denmark)

Interest on Dielectric ElectroActive Polymer (DEAP) generators has aroused among scientists in recent years, due to the former ones' documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter. On top of that, the shortage of commercially-available, high-efficient, high-voltage, low-power semiconductor devices limits the effective operational range of the power electronic converter. In this paper, a bidirectional tapped-inductor buck-boost converter is proposed, addressing high-efficient high step-up and high step-down voltage conversion ratios, for energy harvesting applications based on DEAP generators. The effective operational range of the converter is extended, by replacing its high-side switch with a string of three serialized MOSFETs, to accommodate the need for high-efficient high-voltage operation. Experiments conducted on a single DEAP generator - part of a quadruple DEAP generator energy harvesting system with all elements installed sequentially in the same circular disk with a 90 phase shift - validate the applicability of the proposed converter, demonstrating energy harvesting of 0.26 J, at 0.5 Hz and 60 % delta-strain; characterized by an energy density of 1.25 J per kg of active material.

Dimopoulos, Emmanouil; Munk-Nielsen, Stig

2014-01-01

252

Experimental Studies Towards a DC-DC Conversion Powering Scheme for the CMS Silicon Strip Tracker at SLHC  

CERN Document Server

The upgrade of the CMS silicon tracker for the Super-LHC presents many challenges. The distribution of power to the tracker is considered particularly difficult, as the tracker power consumption is expected to be similar to or higher than today, while the operating voltage will decrease and power cables cannot be exchanged or added. The CMS tracker has adopted parallel powering with DC-DC conversion as the baseline solution to the powering problem. In this paper, experimental studies of such a DC-DC conversion powering scheme are presented, including system test measurements with custom DC-DC converters and current strip tracker structures, studies of the detector susceptibility to conductive noise, and simulations of the effect of novel powering schemes on the strip tracker material budget.

Klein, K; Jussen, R; Karpinski, W; Merz, J; Sammet, J

2009-01-01

253

An efficiency improved single-phase PFC converter for electric vehicle charger applications  

DEFF Research Database (Denmark)

This paper presents an efficiency improved single-phase power factor correction (PFC) converter with its target application to plug-in hybrid electric vehicle (PHEV) charging systems. The proposed PFC converter features sinusoidal input current, three-level output characteristic, and wide range of output DC voltage. Moreover, the involved DC/DC buck conversion stage may only need to convert partial input power rather than full scale of input power, and therefore the system overall efficiency can be much improved. Through proper control of the buck converter, it is also possible to mitigate the double-line frequency ripple power that is inherent in a single-phase AC/DC system. Both simulation and experimental results are presented to show the effectiveness of this converter.

Zhu, Dexuan; Tang, Yi

2013-01-01

254

A Single Phase to Three Phase PFC Half-Bridge Converter Using BLDC Drive with SPWM Technique.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a buck half-bridge DC-DC converter is used as a single-stage power factor correction (PFC) converter for feeding a voltage source inverter (VSI) based permanent magnet brushless DC motor (BLDC) drive. The front end of this PFC converter is a diode bridge rectifier (DBR) fed from single-phase AC mains. The BLDC is used to drive a compressor load of an air conditioner through a three-phase VSI fed from a controlled DC link voltage. The speed of the compressor is controlled to ach...

Srinu Duvvada; Manmadha Kumar B

2014-01-01

255

Diseño estático de un convertidor DC/DC reductor-elevador bidireccional  

Directory of Open Access Journals (Sweden)

Full Text Available This paper shows a buck-boost converter static design with 3 switches and cascade connection. The main application of the converter is the battery management on uninterruptible power supplies, cotrolling energy flow and regulating the DC supply voltage for the different battery operation modes as source and sink.

Marcela González Valencia

2010-06-01

256

Diseño estático de un convertidor DC/DC reductor-elevador bidireccional  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper shows a buck-boost converter static design with 3 switches and cascade connection. The main application of the converter is the battery management on uninterruptible power supplies, cotrolling energy flow and regulating the DC supply voltage for the different battery operation modes as source and sink.

Marcela González Valencia; Alfonso Alzate Gómez

2010-01-01

257

Exploration of Charge Recycling DC-DC Conversion Using a Switched Capacitor Regulator  

Directory of Open Access Journals (Sweden)

Full Text Available The increasing popularity of DVFS (dynamic voltage frequency scaling schemes for portable low power applications demands highly efficient on-chip DC-DC converters. The primary aim of this work is to enable increased efficiency of on-chip DC-DC conversion for near-threshold operation of multicore chips. The idea is to supply nominal (high off-chip voltage to the cores which are then “voltage-stacked” to generate the near-threshold (low voltages based on Kirchhoff’s voltage law through charge recycling. However, the effectiveness of this implicit down-conversion is affected by the current imbalance among the cores. The paper presents a design methodology and optimization strategy for highly efficient charge recycling on-chip regulation using a push-pull switched capacitor (SC circuit. A dual-boundary hysteretic feedback control circuit has been designed for stacked loads. A stacked-voltage domain with its self-regulation capability combined with a SC converter has shown average efficiency of 78%–93% for 2:1 down-conversion with ILoad (max of 200 mA and workload imbalance varying from 0–100%.

Mircea R. Stan

2013-07-01

258

A Closed Form Expression for Predicting Fast Scale Instability in Switching Buck Converters  

Directory of Open Access Journals (Sweden)

Full Text Available Fast scale instability is an undesired phenomenon in switching converters. In past studies, its prediction has been mainly carried out by deriving discrete time models and then linearizing the system in the vicinity of a fixed point. However, the results obtained from such an approach cannot be applied for design purpose except for simple cases of current mode control. Alternatively, in this paper, this phenomenon is analyzed by using a unified formal symbolic approach which can be applied for different control strategies. This approach is based on expressing the condition for fast scale instability occurrence using Fourier series and then converting the result into a matrix form expression which depends explicitly on the system parameters making the results directly applicable for design purpose. Under certain practical conditions concerning these parameters, the matrix form expression can be approximated by standard polynomial functions depending on the operating duty cycle. The approximating polynomial functions are widely related to the well known Clausen polynomial functions. The results presented in this work clearly generalize the well known stability condition of current mode control.

El Aroudi Abdelali

2012-07-01

259

Period-doubling bifurcation in two-stage power factor correction converters using the method of incremental harmonic balance and Floquet theory  

Science.gov (United States)

In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC—DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated post-regulator DC—DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis.

Wang, Fa-Qiang; Zhang, Hao; Ma, Xi-Kui

2012-02-01

260

Convertidor buck-boost controlado digitalmente con histeresis cero mediante un dsp; Back-Booost Converter digitally controlled by zero hysteresis method, using DSP  

Directory of Open Access Journals (Sweden)

Full Text Available En este trabajo se estudia el comportamiento de un convertidor electrónico en configuración buck-boost. Elobjetivo del controlador es hacer el rastreo de señales sinusoidales usando un controlador con histéresiscero, es decir que el usuario pueda tener a la salida cualquier señal a un nivel más alto de potencia y conla característica que esta señal deseada es regulada variable en frecuencia, en amplitud y forma de onda.El controlador es rápido pues se comprobó en el laboratorio que ante perturbaciones en la carga y en laseñal de referencia, se comporta adecuadamente. Se implementó el convertidor usando un inversormonofásico en configuración de medio puente y se controla el sistema con un prototipo rápido de control(RCP DS1104 en tiempo real. In this work, we analysed the behaviour of a buck-boost electronic converter. The objective of the zerohysteresis controller is to track user defined sinusoidal signals, usually featuring high power level andvariable frequency, amplitude and wave form. The controller was implemented in the laboratory, whereload and reference signal disturbances were introduced. The controller achieved a fast and adequatebehaviour. The converter was implemented using a half bridge monophasic inverter, and a rapid controlprototyping (RCP DS1104 in real time for the control task.

Fredy Edimer Hoyos Velasco

2011-02-01

 
 
 
 
261

Achieving Maximum Power from Thermoelectric Generators with Maximum-Power-Point-Tracking Circuits Composed of a Boost-Cascaded-with-Buck Converter  

Science.gov (United States)

We propose a way of achieving maximum power and power-transfer efficiency from thermoelectric generators by optimized selection of maximum-power-point-tracking (MPPT) circuits composed of a boost-cascaded-with-buck converter. We investigated the effect of switch resistance on the MPPT performance of thermoelectric generators. The on-resistances of the switches affect the decrease in the conversion gain and reduce the maximum output power obtainable. Although the incremental values of the switch resistances are small, the resulting difference in the maximum duty ratio between the input and output powers is significant. For an MPPT controller composed of a boost converter with a practical nonideal switch, we need to monitor the output power instead of the input power to track the maximum power point of the thermoelectric generator. We provide a design strategy for MPPT controllers by considering the compromise in which a decrease in switch resistance causes an increase in the parasitic capacitance of the switch.

Park, Hyunbin; Sim, Minseob; Kim, Shiho

2015-01-01

262

Variable-frequency Pulse-Width-Modulation (PWM) for zero voltage switching in a boost dc-dc regulator  

Science.gov (United States)

A technique for operating a pulse width modulated (PWM) dc-dc regulator in the boost mode while switching the MOSFET when the drain-to-source potential is near zero volts was developed and is described. This is accomplished by using frequency-modulation in addition to pulse width modulation. Zero-voltage switching will provide power converter designers an alternative for designing high frequency converters with minimal transient turn-on losses, the predominant form of converter losses experienced in high frequency operation. High frequency operation will result in smaller reactive components, which produce higher power density converters, as well as increasing the transient response of the regulated converter. In addition to allowing for high frequency operation, the design exhibits many desirable power switch properties, such as limiting the peak voltage to the output voltage level and operating with the minimum possible current levels for a given power requirement. A circuit built and tested utilizing zero-voltage switching in a regulated boost converter verified the principles of operation for yielding a high efficiency, high frequency converters.

Hunter, Daniel S.

1990-03-01

263

Investigation of Buck Converter Radiated Emissions (150 kHz - 30 MHz) Measured according to CISPR 25  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Electromagnetic compatibility and compliance with relevant standards is imperative for commercial success for any type of electronic equipment. Since more and more electronics are constantly added into today’s vehicles, this is a highly significant matter in the automotive business. The primary source of electric energy in an on-road vehicle is typically a 12 or 24 volt battery; this makes voltage step down converters ubiquitous in virtually any automotive electronic system. In strive for e...

Murase, John Takeshi

2013-01-01

264

ZVS Operating Region of Multiresonant DC/DC Boost Conveter  

Directory of Open Access Journals (Sweden)

Full Text Available Electromagnetic phenomena that occur during stable operation in resonant circuits of multiresonant ZVS boost converter are described, which can be applied in many fields of the needs of DC voltage electricity. The operating region of the converter is defined which assures the circuit’s operation in which semiconductor elements are switched at zero voltage (ZVS. Conditions delimiting the ZVS operating region are provided. Analysis of the circuit’s operation is based on results of simulation testing by means of Simplorer software.

Elzbieta Szychta

2007-01-01

265

DC-DC Type High-Frequency Link DC for Improved Power Quality of Cascaded Multilevel Inverter  

Science.gov (United States)

Multilevel inverters are emerging as a new breed of power converter options for power system applications. Recent advances in power switching devices enabled the suitability of multilevel inverters for high voltage and high power applications because they are connecting several devices in series without the need of component matching. Usually, a transformerless battery energy storage system, based on a cascaded multilevel inverter, is used as a measure for voltage and frequency deviations. System can be reduced in size, weight, and cost of energy storage system. High-frequency link circuit topology is advantageous in realizing compact and light-weight power converters for uninterruptible power supply systems, new energy systems using photovoltaic-cells, fuel-cells and so on. This paper presents a DC-DC type high-frequency link DC (HFLDC) cascaded multilevel inverter. Each converter cell is implemented a control strategy for two H-bridge inverters that are controlled with the same multicarrier pulse width modulation (PWM) technique. The proposed cascaded multilevel inverter generates lower voltage total harmonic distortion (THD) in comparison with conventional cascaded multilevel inverter. Digital simulations are carried out using PSCAD/EMTDC to validate the performance of the proposed cascaded multilevel inverter.

Sadikin, Muhammad; Senjyu, Tomonobu; Yona, Atsushi

2013-06-01

266

Grid converter for LED based intelligent light sources  

DEFF Research Database (Denmark)

The purpose of this thesis was to investigate the applicability and effects of digital control to line connected switched mode power supplies with power factor correction. The main approach was cost effectiveness with high efficiency. This involved hardware design for increased switching frequency to reduce the size of the magnetic components. A description of different grid regulations was given followed by a set of converter topologies and controllers. Different control techniques were pointed out. Among the listed topologies and control solutions few were selected for further analysis, design and implementation. Many of different hardware and control solutions available on the market were investigated. Most of the commercial power supplies are controlled by dedicated analog controllers in form an integrated circuit. Thus a survey was conducted to analyze the available state-of-art analog controllers and their implemented control algorithms. As digital control has to be competitive with the existing solutions it was investigated what digital signal processing solutions exist. A performance and cost comparison was also presented. The chosen converter topologies were thoroughly analyzed. Different converters were chosen for different power levels. At low power simple boost converter as power factor corrector (PFC) and a RCD-clamped forward converter was chosen as DC-DC converter. This with has double output and coupled lter inductor. To design a digital controller with the tools of the classical control theory a small signal linearized model of the converter is needed. Detailed modeling and linearizing of the boost converter is presented. At high power level interleaving technique is frequently used to reduce the current stress on the switching components. Though the number of magnetic components is increased they became smaller in size resulting in smaller current ripple through them. An interleaved boost converter with two legs is selected as PFC converter. It was shown that the small signal model of theinterleaved converter is similar to the simple boost converter. Only the simple inductor has to be replaced by the paralleled inductors of each leg. This statement is valid only if the total inductor current is controlled rather than controlling the current in each leg. As second stage a phase-shifted full-bridge converter with synchronous rectication and current doubler was selected. It was shown that for output current and voltage control this topology can be modeled as a interleaved synchronous buck converter. As it can be seen interleaving technique is also present in this topology. For this topology a fuzzy logic voltage controller is proposed and compared to the traditional PI controller. After modeling the converters controllers can be designed. The controller design was interconnected with the hardware design and control platform. Thus two dfferent prototypes were designed and built with two dierent digital controllers and the controller design, analysis and implementation was based on these two case studies. The first prototype was a 70 W two-stage PFC and DC-DC converter with boost and forward converters. Average current mode control was selected, designed, simulated an implemented for the boost PFC converter. The two-loop control structure (fast internal current loop and lower bandwidth external voltage loop) was designed for nominal power but system behavior was also analyzed for low-load conditions. The controller was simulated in Matlab/Simulink using PLECS library and embedded Matlab function. All the parameters were treated and scaled just as they appear in the ADC interrupt of the 16 bit fixed point dsPIC30F1010 microcontroller. Peak current control was implemented for the forward converter, using analog comparator module of the digital-signal controller. The waveforms, eciency and power factor results were compared to the performance of an identical two stage 70 W power supply controlled with an analog PFC/PWM integrated circuit. The second prototype was a 600 W two-stage PFC and DC-DC converter with i

Török, Lajos

2011-01-01

267

Digital Sliding-Mode Controller For High-Frequency DC/DC SMPS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Digital control technique is becoming an attractive alternative for high-frequency switching mode power supply (SMPS). This paper introduces a fully synthesizable digital sliding-mode (SM) controller for high-frequency dc/dc SMPS. The proposed SM controller is associated with a digital pulsewidth modulation (DPWM) block to operate at constant and high switching frequency compared to already published approaches. The digital SM controller is experimentally validated by means of field-programma...

Guo, Shuibao; Lin-shi, Xuefang; Allard, Bruno; Gao, Yanxia; Yi, Ruan

2010-01-01

268

Control en modo deslizante aplicado a la generación de señal en convertidores conmutados DC/DC  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Tradicionalmente, el diseño de sistemas de control en convertidores conmutados DC/DC se ha realizado mediante técnica de modulación de anchura de pulsos (PWM); sin embargo, la utilización de la teoría de sistemas de estructura variable aplicada a las topologías convertidotas, así como la teoría de control no lineal permiten obtener características de mayor robustez en insensibilidad frente a variaciones paramétricas y perturbaciones externas. De este modo, existe la posibilidad de d...

Biel Sole?, Domingo

1999-01-01

269

Basic circuits to design switched-based DC-DC converters  

Directory of Open Access Journals (Sweden)

Full Text Available El propósito de este artículo es doble. Por un lado, se presentan conceptos básicos de circuitos conmutados para diseñar un convertidor CD–CD y, por el otro, se rescatan definiciones de electrónica de potencia asociadas a redes eléctricas simples. En el análisis de esas redes es necesario tomar en cuenta no solo las no idealidades de los convertidores sino también cómo minimizar pérdidas de potencia. Porque las perdidas de potencia pueden ser minimizadas aumentando la frecuencia de reloj de los convertidores conmutados, se presentan resultados experimentales de generadores de reloj. Estos circuitos fueron implementados con componentes de bajo costo.

F. Sandoval-Ibarra

2007-01-01

270

Implementation of DC-DC converter with maximum power point tracking control for thermoelectric generator applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A heavy duty vehicle looses approximately 30-40 % of the energy in the fuel as waste heat through the exhaust system. Recovering this waste heat would make the vehicle meet the legislative and market demands of emissions and fuel consumption easier. This recovery is possible by transforming the waste heat to electric power using a thermoelectric generator. However, the thermoelectric generator electric characteristics makes direct usage of it unprotable, thus an electric power conditioner is ...

Jahanbakhsh, David

2012-01-01

271

Modular DC/DC Converter for DC Distribution and Collection Networks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A major change in the electrical transmission and distribution system is taking place in Europe at the moment. The shift from a centralised energy production to a distributed generation profoundly changes the behaviour of the grid. Environmental or social issues associated with the construction of new power lines to relieve bottlenecks, together with aged equipment dating from the 1960s, pose some serious challenges to government, the research communi...

Kenzelmann, Stephan

2012-01-01

272

Usign Planar Transformers in Soft Switching DC/DC Power Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In recent years, the demand for wide applications of highly regulated, reliable power supplies, and the desire to have smaller size, lighter weight and higher efficiency of power electronics systems has been increased. The tallest and heaviest components on printed-circuit-boards are often magnetic components. The answer for miniaturization and material performance can be planar magnetic technology. This paper focuses on the power planar magnetic circuits, with respect to application possibil...

Gabriel Kacor; Pavol Spanik; Ivan Feno

2004-01-01

273

Usign Planar Transformers in Soft Switching DC/DC Power Converters  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years, the demand for wide applications of highly regulated, reliable power supplies, and the desire to have smaller size, lighter weight and higher efficiency of power electronics systems has been increased. The tallest and heaviest components on printed-circuit-boards are often magnetic components. The answer for miniaturization and material performance can be planar magnetic technology. This paper focuses on the power planar magnetic circuits, with respect to application possibilities of these alternative and attractive magnetic components in modern, soft switching, low profile power supplies.

Pavol Spanik

2004-01-01

274

Selection Criteria and Analysis of LCC Resonant DCDC Converters for Automotive Applications  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a technique is developed for the selection of LCC topologies for automotive applications. All available LCC topologies are categorised based on the order of their voltage gain expression. Source/sink requirement for automotive applications is specified based on which some topologies are found to be realizable. Voltage gain expressions for these topologies are obtained and plotted. From the voltage gain plot, two candidate topologies are chosen. Closed form expressions for current gain, stress across resonant tank elements, circulating reactive power and stored energy in the tank are obtained. In addition, the optimum value of Q which results in smallest possible resonant tank is determined and is found to be 0.545.

Prabhakar Mahalingam

2009-06-01

275

A DC-DC Converter-Based PEM Fuel Cell System Emulator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Proton Exchange Membrane Fuel Cell (PEMFC) is being investigated as an alternate power source for various applications as transportation and emergency power supplies. Fuel cell systems are characterized by high costs and complex auxiliary devices. For this reason, a fuel cell emulator can be used as a suitable and economic alternative to a real one for developing and testing a fuel cell power conditioning system. The fuel cell emulator must be able to reproduce the FC nonlinear output vol...

Rezzak, Daoud; Khoucha, Farid; Benbouzid, Mohamed; Kheloui, Abdelaziz; Mamoune, Abdeslam

2011-01-01

276

FC/Battery Power Management for Electric Vehicle Based Interleaved DC-DC Boost Converter Topology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Due to the fact that the environmental issues have become more serious recently, interest in renewable energy systems, such as, fuel-cells (FCs) has increased steadfastly. Among many types of FCs, proton exchange membrane FC (PEMFC) is one of the most promising power sources due to its advantages, such as, low operation temperature, high power density and low emission. However, using only PEMFC for electric vehicle may not be feasible to satisfy the peak demand changes especially during accel...

Benrabah, Ali; Khoucha, Farid; Herizi, Omar; Benbouzid, Mohamed; Kheloui, Abdelaziz

2013-01-01

277

Design of Feedback Controller for Boost Converter Using Optimization Technique  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper a new method of controller design for boost type dc-dc converter is proposed. A feedback controller for DC-DC boost converter is designed to obtain constant output voltage of 24v.The optimal values of feedback controller is obtained using Genetic Algorithm (GA). Design equations are derived and it is modeled in MATLAB. Extensive simulation is carried out with linear controller parameters and the results are presented. To compare the output ...

Sesha Giri Rao Galam; Raghu, S.; Rajasekaran, N.

2012-01-01

278

Recovery Act: Integrated DC-DC Conversion for Energy-Efficient Multicore Processors  

Energy Technology Data Exchange (ETDEWEB)

In this project, we have developed the use of thin-film magnetic materials to improve in energy efficiency of digital computing applications by enabling integrated dc-dc power conversion and management with on-chip power inductors. Integrated voltage regulators also enables fine-grained power management, by providing dynamic scaling of the supply voltage in concert with the clock frequency of synchronous logic to throttle power consumption at periods of low computational demand. The voltage converter generates lower output voltages during periods of low computational performance requirements and higher output voltages during periods of high computational performance requirements. Implementation of integrated power conversion requires high-capacity energy storage devices, which are generally not available in traditional semiconductor processes. We achieve this with integration of thin-film magnetic materials into a conventional complementary metal-oxide-semiconductor (CMOS) process for high-quality on-chip power inductors. This project includes a body of work conducted to develop integrated switch-mode voltage regulators with thin-film magnetic power inductors. Soft-magnetic materials and inductor topologies are selected and optimized, with intent to maximize efficiency and current density of the integrated regulators. A custom integrated circuit (IC) is designed and fabricated in 45-nm CMOS silicon-on-insulator (SOI) to provide the control system and power-train necessary to drive the power inductors, in addition to providing a digital load for the converter. A silicon interposer is designed and fabricated in collaboration with IBM Research to integrate custom power inductors by chip stacking with the 45-nm CMOS integrated circuit, enabling power conversion with current density greater than 10A/mm2. The concepts and designs developed from this work enable significant improvements in performance-per-watt of future microprocessors in servers, desktops, and mobile devices. These new approaches to scaled voltage regulation for computing devices also promise significant impact on electricity consumption in the United States and abroad by improving the efficiency of all computational platforms. In 2006, servers and datacenters in the United States consumed an estimated 61 billion kWh or about 1.5% of the nation's total energy consumption. Federal Government servers and data centers alone accounted for about 10 billion kWh, for a total annual energy cost of about $450 million. Based upon market growth and efficiency trends, estimates place current server and datacenter power consumption at nearly 85 billion kWh in the US and at almost 280 billion kWh worldwide. Similar estimates place national desktop, mobile and portable computing at 80 billion kWh combined. While national electricity utilization for computation amounts to only 4% of current usage, it is growing at a rate of about 10% a year with volume servers representing one of the largest growth segments due to the increasing utilization of cloud-based services. The percentage of power that is consumed by the processor in a server varies but can be as much as 30% of the total power utilization, with an additional 50% associated with heat removal. The approaches considered here should allow energy efficiency gains as high as 30% in processors for all computing platforms, from high-end servers to smart phones, resulting in a direct annual energy savings of almost 15 billion kWh nationally, and 50 billion kWh globally. The work developed here is being commercialized by the start-up venture, Ferric Semiconductor, which has already secured two Phase I SBIR grants to bring these technologies to the marketplace.

Shepard, Kenneth L

2013-03-31

279

Stability Analysis Of Sepic Converter Using Matlab/Simulink  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract: DC-DC converter is a converter where we are regulating the input voltage to get the desired output voltage which is either greater than or equal to or less than the input voltage with positive or negative polarity. A lot of dc-dc converters are available in the world out of which SEPIC (Single-Ended Primary-Inductor Converter) converter is one of them. To analyse the converter, a lot of techniques are available. This paper presents the use of MATLAB/SIMULINK to study the stability o...

Sidharth Sabyasachi; Pratyusha Mohanty

2014-01-01

280

A Novel V-I Converter Used in the Slope Compensation of a Boost Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A novel voltage to current circuit used in the slopecompensation of a boost DC-DC converter is proposed.Compared with the normal V-I converter, it has a better linearrelation and a larger input voltage range. It can implementslope compensation of the power converter, eliminate thesub-harmonic oscillation and decrease the noise infectioneffectively.

Yuan-kai Jian; Gang-jun Xie

2012-01-01

 
 
 
 
281

Power Converters Secure Electronics in Harsh Environments  

Science.gov (United States)

In order to harden power converters for the rigors of space, NASA awarded multiple SBIR contracts to Blacksburg, Virginia-based VPT Inc. The resulting hybrid DC-DC converters have proven valuable in aerospace applications, and as a result the company has generated millions in revenue from the product line and created four high-tech jobs to handle production.

2013-01-01

282

Analysis and Design of Embedded Controlled Parallel Resonant Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Microcontroller based constant frequency controlled full bridge LC parallel resonant converter is presented in this paper for electrolyser application. An electrolyser is a part of renewable energy system which generates hydrogen from water electrolysis. The DC power required by the electrolyser system is supplied by the DC-DC converter. Owing to operation under constant frequency, the filter designs are simplified and utilization of magnetic components is improved. This converter has advantages like high power density, low EMI and reduced switching stresses. DC-DC converter system is simulated using MATLAB, Simulink. Detailed simulation results are presented. The simulation results are compared with the experimental results.

P. CHANDRASEKHAR

2009-07-01

283

New Geometry Integrated Inductors in Two-channel Interleaved Bidirectional Converter  

DEFF Research Database (Denmark)

A new geometry of integrated inductors for twochannel interleaved bidirectional converter is presented in this paper. The new geometry module integrates two individual inductors by stacking three I-cores. The middle I-core provides a shared flux path with low reluctance which uncouples the two inductors. The air gaps are constructed by separating the I-cores using copper foil windings with well-defined thickness. In this work, inverse connection and direct connection for the two integrated inductors have been analyzed. For the inverse connection, a unique saturation behavior in the middle I-core has been shown. The integrated inductors with new geometry make it possible to build low-profile, low-cost, flexibility DC/DC converters, and it can be extensively designed for low-voltage and high-current required by modern digital applications. Experiment results obtained from a 48V-12V 30A two-phase interleaved buck converter, demonstrates the difference in the inverse connection and the direct connection. Both efficiencies are above 91% from half to full output current.

Ouyang, Ziwei; Thomsen, Ole Cornelius

2010-01-01

284

A Single Phase to Three Phase PFC Half-Bridge Converter Using BLDC Drive with SPWM Technique.  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a buck half-bridge DC-DC converter is used as a single-stage power factor correction (PFC converter for feeding a voltage source inverter (VSI based permanent magnet brushless DC motor (BLDC drive. The front end of this PFC converter is a diode bridge rectifier (DBR fed from single-phase AC mains. The BLDC is used to drive a compressor load of an air conditioner through a three-phase VSI fed from a controlled DC link voltage. The speed of the compressor is controlled to achieve energy conservation using a concept of the voltage control at DC link proportional to the desired speed of the BLDC. Therefore the VSI is operated only as an electronic commutator of the BLDC. The stator current of the BLDC during step change of reference speed is controlled by a rate limiter for the reference voltage at DC link. The proposed BLDC drive with voltage control based PFC converter is designed, modeled and its performance is simulated in Matlab-Simulink environment for an air conditioner compressor driven through a 1.5 kW, 1500 rpm BLDC motor. The evaluation results of the proposed speed control scheme are presented to demonstrate an improved efficiency of the proposed drive system with PFC feature in wide range of the speed and an input AC voltage.

Srinu Duvvada

2014-07-01

285

Isolated and soft-switched power converter  

Science.gov (United States)

An isolated and soft-switched power converter is used for DC/DC and DC/DC/AC power conversion. The power converter includes two resonant tank circuits coupled back-to-back through an isolation transformer. Each resonant tank circuit includes a pair of resonant capacitors connected in series as a resonant leg, a pair of tank capacitors connected in series as a tank leg, and a pair of switching devices with anti-parallel clamping diodes coupled in series as resonant switches and clamping devices for the resonant leg. The power converter is well suited for DC/DC and DC/DC/AC power conversion applications in which high-voltage isolation, DC to DC voltage boost, bidirectional power flow, and a minimal number of conventional switching components are important design objectives. For example, the power converter is especially well suited to electric vehicle applications and load-side electric generation and storage systems, and other applications in which these objectives are important. The power converter may be used for many different applications, including electric vehicles, hybrid combustion/electric vehicles, fuel-cell powered vehicles with low-voltage starting, remote power sources utilizing low-voltage DC power sources, such as photovoltaics and others, electric power backup systems, and load-side electric storage and generation systems.

Peng, Fang Zheng (Knoxville, TN); Adams, Donald Joe (Knoxville, TN)

2002-01-01

286

Analysis and Implementation of Efficient BLDC Motor Drive with Different Converter Systems  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This Paper deals with analysis of efficient BLDC motor drive with various converter systems. Performance of the drive system is compared based on THD and PF at the AC mains with the following converter topology: Conventional DC-DC converter, SEPIC and CSC converter. The complete drive system is designed and modeled in MATLAB/Simulink environment for speed control over a wide range.

Angeline Jayachandran*1,; Lakshmi, G. R. P.

2014-01-01

287

Analysis of Photovoltaic Fed Partially Isolated Three-Port Full Bridge Converter with the Centralised Controller  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper analysis of an efficient topology of the three-port full bridge dc-dc converter is presented. This topology is promising with the view points of centralised control, compact design as it is capable of interfacing many numbers of ports with less number of switches, low cost, simple and fast power flow management with reduced conversion process. In a stand-alone system this topology is used to interface renewable energy sources and the load along with the energy storage device. Thus the proposed topology interfaces three ports: as one source port, one bidirectional storage port and an isolated output port. The key feature of this converter is that it performs buck-boost operation on the input port side to obtain power balance in the system with the centralised controller. The centralised controller was implemented by using proportional Integral (PI controller. Such that it is used to track maximum power from the Photovoltaic (PV system and to regulate output voltage by controlling the charging and the discharging characteristics of the battery. Zero voltage switching (ZVS is also achieved in all the switches by using the energy stored in the leakage inductance of the transformer, output filter inductance and capacitance.

Venmathi M

2014-07-01

288

Embedded Control of LCL Resonant Converter Analysis, Design, Simulation and Experimental Results  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Objective of this paper is to give more insight into CCM Operation of the LCL Converter to obtain op-timum design using state-space analysis and to verify the results using PSPICE Simulation for wide variation in loading conditions. LCL Resonant Full Bridge Converter (RFB) is a new, high performance DC-DC con-verter. High frequency dc-dc resonant converters are widely used in many space and radar power supplies owing to their small size and lightweight. The limitations of two element reso...

Christober Asir Rajan, C.; Selvaperumal, S.

2009-01-01

289

SMALL-SIGNAL ANALYZING OF SEPARATELY EXCITED DC MOTOR FED DC - DC CHOPPER  

Directory of Open Access Journals (Sweden)

Full Text Available Choppers are widely used in order to get smooth speed characteristics of DC motors. If the load or input voltage is changed, a feedback control technique is used to get the constant speed. To design the proper feedback control, the transfer function of the chopper-motor combination should be kno\\vn. ln this study, the effort was given to obtain the general black diagram, inciurling the field current and a?1na ture current of chopper-fed DC motor. It can be seen from the black diagram that the chopper circuit modifies the transfer function of the DC motor. DC-DC DARBEL E Y?C? iLE YABANCI UYARTIMLI DC KÜÇÜK S?NY AL ANAL?Z? ÖZET BESLENEN MOT O RUN DC motorlardan düzgün bir h?z karakteristi?i elde etmek için darbeleyiciler çok kullaml?r. E?er yük ya da giri? gerilimi de ?i ?irse, sabit h?z elde etmek için geribeslemeli kontrol tekni?i kuJlan?l?r. Uygun bir geribesleme kontrolu tasarlamak iç? darbeliyici-motor kombinasy onunun transfer fonksiyonu bilinmelidir. -Bu çal??ma da, darbeleyici ile beslenen DC motorun alan ak?m? ve endüvi ak?m?n? da kapsayan genel blok diya?ra?n?n? elde et???ek için çaba gösterilmi?tir. Blok diyagram?ndan görülebilec e?i gibi, darbeleyici devresi DC motorun tra nsfer fonksiyonunu de?i?tirmektedir. I. INTRODUCTI ON Choppers are widely used for speed control of DC separately excited motors as they offer high efficiency, quick response, wide speed control range and regeneration down to very low speeds [ 1] . All chopper circuits can be classified into two groups. (a Load ind ependent choppers? in which the output voltage waveform is either a square wave or can be approximated by a square \\vave. (b Load dependent choppers, in which charging of the commutating capacitor is govemed by load current. In such cases, the output voltage wavefo?m is neither a square wave nor can be approximated by a square wave. Various methods of analyzing of DC motors fed by a chopper with square wave output volta ge are reported in

?SMA?L CO?KUN

1999-12-01

290

HI-BRIDGE RESONANT SOFT-SWITCHED BOOST CONVERTER  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a high step-up DC-DC converter. The proposed converter comprises of a boost converter with an auxiliary switch and resonant circuit. The resonant circuit consists of a resonant inductor, two resonant capacitors, two diodes and an auxiliary switch. These resonant components make partial resonant path for the main and auxiliary switch to perform soft switching under the zero voltage condition using the resonant circuit. The proposed boost converter improves the whole system?...

Elangovan S, Marimuthu M.

2013-01-01

291

The use of power DC-DC converters and gyrators structures for energy processing in photovotaic solar facilities  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This article provides a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain the ...

Marti?nez Garci?a, Herminio

2014-01-01

292

A NEW GENERATION VLSI APPROACH FOR THE PWM CONTROL OF AN INTEGRATED FOUR-PORT DC-DC CONVERTER  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In the recent years, the increase in the petroleum prices, the rapid run out tendency of fossil fuel reserves and their unavoidable harmful effects and political instabilities in the regions of energy sources have been accelerated the studies on the renewable energy systems. Although various renewable energy power generations are in practice today, the most popular is using photovoltaic (PV) arrays and wind generators. Since PV and wind sources can meet the required demand but ...

SANGAMESH SAKRI; Rathod, Kaveri P.; Jayaramaih, G. V.

2012-01-01

293

Non-isolated high ratio DC-DC converter for fuel cell and electrolyzer - GaN transistors  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Development of renewable energy seems inevitable to face the energy challenge of today and tomorrow. However, the power generation of promising renewable sources such as solar or wind power is intermittent and unpredictable due to the dependence of the these sources to the weather. In order to overcome the discontinuous nature of the electricity production and the mismatch between production and consumption, electrical energy storage is needed. In this context, hydrogen battery is one of the ...

Videau, Nicolas

2014-01-01

294

Simulation of High Step-Up DC–DC Converter for Photovoltaic Module Application using MATLAB/SIMULINK  

Digital Repository Infrastructure Vision for European Research (DRIVER)

As per the present scenario lot of power shortages are there in all over the world especially country like India the grid transferring problem is also high. Almost the power from the fossil fuels are becoming so less some of the examples of the fossil fuels are (coal, lignite, oil, and gases).So most of them looking in forward for the power from green or renewable based energies like solar, wind, biomass, tidal etc. Which does not cause any pollution to the environment. In this paper the simu...

Daison Stallon, S.; Vinoth Kumar, K.; Suresh Kumar, S.; Justin Baby

2013-01-01

295

Tribute to Paul Buck  

Directory of Open Access Journals (Sweden)

Full Text Available Paul Buck passed away on January 16, 2008. Respected and admired by his colleagues and friends, he left a legacy of lifelong commitment to ecology and botany. Paul was a founding member of the Board of Directors of the Oklahoma Native Plant Society in 1987, and, after serving on its board for several subsequent terms, he was the second recipient of the ONPS Service Award.

Constance Murray

2008-12-01

296

Bidirectional converter interface for a battery energy storage test bench  

DEFF Research Database (Denmark)

This paper presents the bidirectional converter interface for a 6 kV battery energy storage test bench. The power electronic interface consists a two stage converter topology having a low voltage dc-ac grid connected converter and a new dual active bridge dc-dc converter with high transformation ratio. The dc-dc converter controls the battery charge/discharge current while the grid converter controls the common dc-link voltage and the grid current. The applied control structures and the hardware implementation of both converters are presented, together with their interaction. Experimental results of the test bench show good performance for the bidirectional power flow with a maximum operating power of 100 kW.

Trintis, Ionut; Thomas, Stephan

2011-01-01

297

Implementation of Three Level Integrated AC-DC Converter with Pulse Width Modulation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, implementation of three-level integrated ac–dc converter with pulse width modulation is presented. The proposed converter combines with the operation of the boost power factor correction and the three-level dc–dc converter. The converter is made to operate with two independent controllers which are combined in a single converter. Input controller does PFC and regulates dc bus, output controller regulates the output voltage. Converter operation is explained and power factor ...

Deepak Singh, K.; Rathi, Manish G.

2014-01-01

298

DESIGN AND SIMULATION OF PWM FED TWO-PHASE INTERLEAVED BOOST CONVERTER FOR RENEWABLE ENERGY SOURCE  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Recently dc-dc converters is serving many purposes and is usually required in any applications which has low output voltage such as Fuel cells, Batteries, photo voltaic cells. For designing high efficiency fuel cells which is a clean energy source and has a high energy storage capability, a suitable dc-dc converter is required. One of the challenges in designing the boost converter for high power application is to how to handle the high current at the input side. Among the various topologies ...

Mounica Ganta, Pallamreddy Nirupa

2013-01-01

299

Boost Converter Animation  

Science.gov (United States)

This animation, created by faculty at Dartmouth University, is a boost converter. The resource features other animations such as buck and discontinuous converters. They also add simple diode, bridge and half-wave rectifiers. Although simple in design, this can still be a useful resource for those interested in electrical engineering.

300

Design and Implementation of Power Converters for Hybrid Wind-Solar Energy Conversion System with an Implementation of MPPT  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents the design and implementation of power converters for wind conversion systems. The power converter can not only transfer the power from a wind generator, but also improve the stability and safety of the system. The proposed system consists of a Permanent magnet synchronous generator (PMSG); a DC/DC boosts converter, a bi-directional DC/DC converter and a full-bridge DC/AC inverter. The wind generator is the main power source of the system, and the battery is used for energ...

Sridhar Babu, G.

2013-01-01

 
 
 
 
301

Boost Converter with Three-State Switching Cell and Integrated Magnetics  

DEFF Research Database (Denmark)

Fuel cell systems often require high voltage gain and dc-dc step-up converter is a critical part. Scope of this paper is integration of inductor and transformer on a single core. Usage of integrated magnetics improves utilization of magnetic core and thus size and weight of the converter may be reduced.

Klimczak, Pawel; Munk-Nielsen, Stig

2009-01-01

302

A Self-Oscillating Control Scheme for a Boost Converter Providing a Controlled Output Current  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Most switched mode power supplies provide a regulated voltage at their output. However, there are applications requiring a controlled current. Among others are battery chargers, test equipment for converters driven by solar cells, and LED drivers. This paper describes a dc–dc power converter realizing such a current source. The converter is based on a boost converter, supplied by a voltage source and acting as a current source. The boost converter can increase the output voltage above the i...

Knott, Arnold; Pfaffinger, Gerhard R.; Andersen, Michael A. E.

2011-01-01

303

Multi Port Single Stage Power Electronics Converter and Wind PFC Converter for DC Micro Grid Applications  

Directory of Open Access Journals (Sweden)

Full Text Available In this study multi port AC/DC-DC single stage power electronics converter proposed for grid power supply. The topology includes reduced number of active element and passive element. Passive element is used to provide to achieve improved voltage gain and to reduce the voltage stress of input side switches. The active-clamp circuits are used to recycle the energy stored in the leakage inductors and to improve the system performances. Here two input port (wind and battery unit and output port connected to dc grid, battery act as charge unit and source. Efficient wind power conversion is achieved by PFC boost dc-dc converter. Controlled and high step up voltage is supplied to multi-port converter from wind source.

M. Hemachandran

2014-08-01

304

Comparison of PID and Fuzzy Controlled DC to DC Converter with Inductor Resistance.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The DC-DC boost converter reveals highly non-linear and non-minimum phase properties, is very difficult task to design a controller that is healthy against load variation. For this purpose a Fuzzy PID Controller is proposed to control DC-DC boost converter which has a practical inductor and a series resistance. A balancing ProportionalIntegral-Differential (PID) controller to the parallel-damped passivity-based controller PD-PBC is also proposed for removing the steady state error even though...

Anand, R.; Melba Mary, P.

2013-01-01

305

An Effective Wind Energy System based on Buck-boost Controller  

Directory of Open Access Journals (Sweden)

Full Text Available In Domestic Wind Machines, if the wind speed is low, the output voltage is not sufficient to charge the battery as it is lower than the rated charging voltage of the battery. This limits the overall efficiency of the Wind Machine to 20%. This study proposed to design and develop a Buck Boost Controller for the effective utilization of the wind machine. By implementing a controller based Buck Boost converter, the voltage produced at the lower wind speeds can also be utilized effectively by boosting it to the rated charging voltage of the battery. Also if the wind speed is high (>14 m/s, the DC output voltage will increase to more than 65 V. The converter bucks this high voltage to the nominal battery charging voltage (52 V, thereby protecting the battery from over charging voltage. Thus the effective utilization of the wind machine has been achieved by the use of the proposed Buck Boost Controller.

N. Prakash

2013-06-01

306

Diseño de un controlador difuso supervisor para la regulación de un convertidor conmutado elevador / DC-DC Supervisor Fuzzy Controller Design for a Boost Switching DC-DC Regulator  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En este trabajo, se diseña un controlador difuso del tipo Takagi-Sugeno-Kang (TSK) para un regulador elevador conmutado DC-DC que opera a diferentes tensiones en estado estacionario. Este controlador realiza tareas de supervisión mediante su característica zonal. Por un lado, el controlador asigna d [...] iferentes leyes lineales de control acorde al valor de tensión de régimen estacionario y de los límites de aplicación a perturbación en pequeña señal. Por otra parte, el controlador asegura un arranque correcto para alcanzar el valor deseado de tensión de estado estacionario, por medio de una adecuada saturación del modulador de ancho de pulso (PWM) de acuerdo con los principios de control en modo deslizamiento. Como resultado, se logra un comportamiento ecualizado en pequeña señal y un arranque controlado para diferentes tensiones de estado estacionario; por tanto, se amplían las características del regulador. Se presentan resultados de simulación y experimentales realizados sobre un regulador elevador controlado por corriente, operando sobre dos valores de tensión diferentes de estado estacionario que validan el diseño. Abstract in english A complete design of a Takagi-Sugeno-Kang (TSK) fuzzy controller for a PWM boost DC-DC switching regulator operating at different steady-state voltages is presented. This controller performs a supervisory role through its region characteristic. On the one hand, the controller assigns different linea [...] r control laws according to the steady-state voltage value and limits their application to small-signal perturbations. On the other hand, the controller ensures a proper start-up to reach the desired steady-state voltage by means of properly saturating the PWM according to sliding-mode control principles. As a result, both an equalized small signal behavior and a controlled start-up are achieved for different steady-state voltages, thus extending the features of the regulator. Simulation and experimental results carried out on a current-controlled boost regulator operating at two different steady-state

Spartacus, Gomáriz; Francesc, Guinjoan.

2008-11-01

307

High Frequency Soft Switching Of PWM Boost Converter Using Auxiliary Resonant Circuit  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequency of PWM converters is increased its switching losses and conduction losses also in...

Sai Kiran, C. P.; Vishnu Vardhan, M.

2014-01-01

308

A New Asymmetrical Current-fed Converter with Voltage Lifting  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new zero voltage switching current-fed DC-DC converter with high voltage gain. In this converter all switches (main and auxiliary) turn on under zero voltage switching and turn off under almost zero voltage switching due to snubber capacitor. Furthermore, the voltage spike across the main switch due to leakage inductance of forward transformer is absorbed. The flyback transformer which is connected to the output in series causes to high voltage gain and less voltage s...

Delshad, M.

2011-01-01

309

Conference James F.Buckli  

CERN Multimedia

L'association du personnel a le plaisir d'accueillir Mons. James F.Buckli, astronaute, né en 1947. Il a participé à la mission Space Lab D1 qui pour la première fois mettait 8 personnes sur orbite.L'ass.du pers. remercie aussi Gordon White(s) de la mission américaine d'avoir permis d'organiser cette conférence

Buckli,J

1988-01-01

310

Design, Simulation and Hardware Implementation of a Multi Device Interleaved Boost Converter for Fuel Cell Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents the analysis and implementation of a two-phase  Multi Device Interleaved  Boost Converter (MDIBC).  Among the various DC-DC  topologies, Multi device Interleaved converter is considered as a better solution for fuel cell  hybrid vehicles as it reduces the  input current ripple,  output voltage ripple and the size of passive components. Detailed analysis has been done to investigate the benefits of Multi device Interleaved boost converter by comparing  it with th...

Seyezhai, R.

2014-01-01

311

Implementation of Fuzzy Logic controller in Photovoltaic Power generation using Boost Converter and Boost Inverter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Increasing in power demand and shortage of conventional energy sources, researchers are focused on renewable energy. The proposed solar power generation circuit consists of solar array, boost converter and boost inverter. Low voltage, of photovoltaic array, is boosted using dc-dc boost converter to charge the battery and boost inverter convert this battery voltage to high quality sinusoidal ac voltage. The output of solar power fed from boost inverter feed to autonomous load without any inter...

Abubakkar Siddik A; Shangeetha M

2012-01-01

312

An Improved MPPT Interleaved Boost Converter for Solar Electric Vehicle Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An interleaved boost dc/dc converter is developed featuring smaller input/output filters, faster dynamic response and lower device stress than conventional designs, for solar electric vehicle (SEV) applications. The converter is connected between the photovoltaic power generation and dc bus in a multisource energy storage system of a SEV. Typically, interleaved converters require a current control loop to reduce the input current ripples, the output voltage ripples, and the size of passive co...

Khoucha, Farid; Benrabah, Ali; Herizi, Omar; Kheloui, Abdelaziz; Benbouzid, Mohamed

2013-01-01

313

Model of Bi-directional Flyback Converter for Hybrid AC/DC Distribution System  

Directory of Open Access Journals (Sweden)

Full Text Available In this article, a simulation model and concept of two switch bi-directional isolated DC/DC converter is presented. Converter is based on flyback converter type. Also control method for voltage regulation with bi-directional power transfer is presented. Target application of the proposed converter was selected to be a hybrid AC/DC distribution system concept of which was briefly described. The requirement of galvanic isolation in the hybrid AC/DC concept comes from use of shared neutral wire; DC current runs with unbalanced part of AC current in neutral wire. Without galvanic isolation grounded neutral would cause short circuit if DC/DC converter is connected to three phase rectifier or inverter. Simulation was carried out with PSCAD electromagnetic transient simulator.

Riku Pasonen

2013-12-01

314

A SINGLE – STAGE SOLAR POWER CONVERTER FOR PV BATTERY SYSTEM?  

Directory of Open Access Journals (Sweden)

Full Text Available The main concept of the new converter is to use a Single - stage three phase grid ties - solar PV converter to perform dc/dc and dc/ac operations. This converter solution is appealing for PVbattery applications, because it minimizes the number of conversion stages, improving efficiency and reducing cost, weight and volume. This converter solution is appealing for PV-battery application, because it minimizes the number of conversion stages, thereby improving efficiency and reducing cost, weight, and volume. In this paper, a combination of analysis and experimental tests is used to demonstrate the attractive performance characteristics of the proposed RSC.

K Krishna Chaitanya?

2014-10-01

315

DESIGN AND SIMULATION OF PWM FED TWO-PHASE INTERLEAVED BOOST CONVERTER FOR RENEWABLE ENERGY SOURCE  

Directory of Open Access Journals (Sweden)

Full Text Available Recently dc-dc converters is serving many purposes and is usually required in any applications which has low output voltage such as Fuel cells, Batteries, photo voltaic cells. For designing high efficiency fuel cells which is a clean energy source and has a high energy storage capability, a suitable dc-dc converter is required. One of the challenges in designing the boost converter for high power application is to how to handle the high current at the input side. Among the various topologies IBC is a better solution for fuel cell systems due to its increased efficiency, reduced size, current sharing on high power applications, low input current ripple and improved reliability. The various parameters of the PWM based IBC are compared to a conventional boost converter. Simulation studies has been carried out using MATLAB/SIMULINK.

MOUNICA GANTA, PALLAMREDDY NIRUPA, THIMMADI AKSHITHA, R.SEYEZHAI

2013-04-01

316

An Analysis Method of Operation State for Boost Converter with Voltage Feedback Control  

Science.gov (United States)

When system parameters were adjusted, some instability phenomenon could occur in closed-loop DC-DC converter. For improving the stability of converter system, an analysis method of operation state for converter was presented based on the discrete model of continuous conduction mode(CCM) Boost converter with voltage feedback control. This method can avoid fussy derivative operation. The steady equation of CCM Boost converter was deduced and the system parameters condition on which closed-loop instability phenomenon would occur were analyzed, the condition is appropriate to high frequency Boost converter. Corresponding simulation results were given in this paper.

Zhaoxia, Leng; Qingfeng, Liu; Jinkun, Sun; Huamin, Wang

317

Modelling of Photovoltaic System with Converter Topology for Grid fed Operations.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents the performance of a grid connected converter topology for PV array. The system containing solar cell, DC-DC boost converter, inverter and ac load (grid). This paper presents the simulation of a photovoltaic system using MATLAB, which can be representative of PV cell, module and array. The photovoltaic array is designed for 144 V. The proposed PV model was prepared on MATLAB scrip file and input parameters are solar irradiation and temperature. The output current and power...

Umadevi, K.; Nalandha, P.; Chenn Kesavan, C.

2014-01-01

318

Design of High-Efficient Converter for On-board Thermoelectric Generator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The efficiency of internal combustion engines in trucks and passenger cars are low (<40%). Much work has been done to make the engines more efficient internally, by improving the mechanical and electrical components. However, there is still a large amount of fuel power, which gets converted into heat and escapes through exhaust gases as waste heat. Taking advantages of thermoelectricity, part of that heat power can be converted into electrical power. In this paper, the most suitable DC/DC ...

Risseh, Arash; Nee, Hans-peter

2014-01-01

319

Estimation of the Region of Attraction for a Boost DC-AC Converter Control Law  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper is estimated the region of attraction of the nonlinear boost DC-AC converter by Sum of Squares. This is an optimization problem of maximization of the Lyapunov surface subjects to certain strict constraints due to saturation of the control variables of the system and to the composition of the inverter, which is formed from two DC-DC converters with positive voltage.

Albea, Carolina; Gordillo, Francisco

2007-01-01

320

The electrical, thermal and spatial integration of a converter in a power electronic module:  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis is concerned with the design and implementation of a power electronic system (14/42V DC/DC converter) that is implemented in the automotive environment, specifically the engine compartment. The power electronic system must have a high power density while operating in a high temperature environment. Power electronic modules are considered the technology base in which to implement the automotive converter. Of the power electronic modules considered, the Integrated System Module...

Gerber, M. B.

2005-01-01

 
 
 
 
321

Analisys of Current-Bidirectional Buck-Boost Based Automotive Switch-Mode Audio Amplifier  

DEFF Research Database (Denmark)

The following study was carried out in order to assess quantitatively the performance of the buck-boost converter when used as switch-mode audio amplifier. It comprises of, to begin with, the delimitation of design criteria based on the state-ofthe- art solution, which is based in a differential mode buck-based amplifier with a boost converter as power supply. The averaged switch modelling of the differential mode current bidirectional topology is also used, in order to analyze the steady state and frequency domain behaviour of this converter and parameterize it to meet the design criteria. Next, several piecewise-linear simulation results are shown with detail enough to emphasize the features of the converter. A simple prototype is implemented to verify the main predicted features. Presently no previous publication could be found containing a thorough analysis of this topology in such configuration when applied for audio.

Bolten Maizonave, Gert; Andersen, Michael A. E.

2011-01-01

322

Primary Parallel Isolated Boost Converter with Bidirectional Operation  

DEFF Research Database (Denmark)

This paper presents a bidirectional dc/dc converter operated with batteries both in the input and output. Primary parallel isolated boost converter (PPIBC) with transformer series connection on the high voltage side is preferred due to its ability to handle high currents in the low voltage side. The converter has been modeled using non-ideal components and operated without any additional circuitry for startup using a digital soft-start procedure. Simulated and measured loop gains have been compared for the validity of the model. On-the-fly current direction change has been achieved between input and output battery banks with a defined ramp.

Hernandez Botella, Juan Carlos; Mira Albert, Maria del Carmen

2012-01-01

323

High Efficiency Boost Converter with Three State Switching Cell  

DEFF Research Database (Denmark)

The boost converter with the three-state switching cell seems to be a good candidate for a dc-dc stage for non-isolated generators based on alternative energy sources. It provides a high voltage gain, a reduced voltage stress on transistors and limited input current ripples. In this paper the focus is on performance improvement of this type of the converter. Use of foil windings helps to reduce conduction losses in magnetic components and to reduce size of these components. Also it has been demonstrated that the regulation range of this type of converter can be increased by operation with duty cycle lower than 50%.

Klimczak, Pawel; Munk-Nielsen, Stig

2009-01-01

324

Implementation of PMBLDC motor using Cuk PFC converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper aims at an improve speed quality employing Cuk DC-DC converter is used as a power factor correction (PFC) converter for feeding a voltage source inverter (VSI) based permanent magnet brushless DC motor (PMBLDCM) driven air condition. This PFC converter is front end diode bridge rectifier (DBR) fed from single-phase AC mains and connected to a three phase voltage source (VSI) feeding the permanent magnet brushless DC motor (PMBLDCM). The PMBLDC Motor is used to drive a compressor lo...

Padmini Sahu,; Prof. Anurag Singh Tomer,

2012-01-01

325

An Effective Wind Energy System based on Buck-boost Controller  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In Domestic Wind Machines, if the wind speed is low, the output voltage is not sufficient to charge the battery as it is lower than the rated charging voltage of the battery. This limits the overall efficiency of the Wind Machine to 20%. This study proposed to design and develop a Buck Boost Controller for the effective utilization of the wind machine. By implementing a controller based Buck Boost converter, the voltage produced at the lower wind speeds can also be utilized effectively by boo...

Prakash, N.; Ranithottungal, D.; Sundaram, M.

2013-01-01

326

Analysis of current-bidirectional buck-boost based switch-mode audio amplifier  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The following studdy was carried out in order to assses quantitatively the performannce of the buck--boost converter whhen used as swiitch-mode audio amplifier. It comprises of, to beggin with, the de limitation of design criteria bassed on the state of-the-art solution, which is based in a differential mode buckbased amplifier with a boost converter as power supply. The averaged switch modelling of the differential mode current bidirectional topology is also used, in ...

Bolten Maizonave, Gert; Andersen, Michael A. E.; Kjærgaard, Claus; Lund, Kristian L.; Hansen, Lars B. R.

2011-01-01

327

Buck-Boost Impedance Networks  

DEFF Research Database (Denmark)

Most inverters designed to date can only perform either voltage-buck or boost operation with buck-boost mode usually attained by introducing additional active semiconductor devices and passive components to the inverters. Although effective, adding active switches will complicate the inverter control, and push up the overall system costs. Therefore, alternative topological solutions are of interest, and should preferably be implemented using only passive LC elements and diodes, connected as unique impedance networks. A number of possible network configurations are now investigated in this paper, and are respectively named as Z-source, H-source, EZ-source and their respective "inverted" variants. The presented impedance networks can either be used with a traditional voltage-source or current-source inverter, and can either be powered by a voltage or current source. All impedance networks are shown to produce the same voltage gain under the same operating conditions, but structurally, they have their respectiveadvantages and disadvantages, which are thoroughly described throughout the paper. Experimental results captured using a laboratory prototype are also presented for confirming the practicalities and performances of the described impedance networks.

Goh, Ailian; Gao, Feng

2007-01-01

328

Analysis and Design of a Higher Current ZVS-PWM Converter for Industrial Applications  

Directory of Open Access Journals (Sweden)

Full Text Available A new auxiliary circuit that can be implemented in DC-DC and AC-DC ZVS-PWM converters is proposed in the paper. The circuit is for ZVS-PWM converters used in applications where high-frequency operation is needed and the load current is higher than that of typical ZVS-PWM converters. In the paper, the operation of a new ZVS-PWM converter is described, its steady-state operation is analyzed, and a procedure for its design is derived and then demonstrated. The feasibility of the new converter is confirmed by experimental results obtained from a prototype.

Navid Golbon

2013-03-01

329

Battery Management System—Balancing Modularization Based on a Single Switched Capacitor and Bi-Directional DC/DC Converter with the Auxiliary Battery  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small ...

Mohamed Daowd; Mailier Antoine; Noshin Omar; Philippe Lataire; Peter Van Den Bossche; Joeri van Mierlo

2014-01-01

330

High Gain Interleaved Boost Converter for Fuel Cell Applications  

Directory of Open Access Journals (Sweden)

Full Text Available Fuel cell is one of the promising technologies for distributed generation. For designing high efficiency fuel cell power systems, a suitable DC-DC converter is required. Among the various topologies, interleaved converters using switched capacitor are considered as a better solution for fuel cell systems due to high conversion efficiency. The objective of the paper is to design and implement a high gain interleaved converter using switched capacitors for fuel cell systems. In the proposed interleaved converter, the front end inductors are magnetically cross-coupled to improve the electrical performance and reduce the weight and size. Also, switched capacitors are used to improve the voltage gain of the converter. The proposed converter has been performed. Simulation study of interleaved converter using switched capacitors interfaced with fuel cells has been studied using Matlab/Simulink. A prototype has been developed to verify the simulation results.

R. Seyezhai

2013-12-01

331

High Gain Interleaved Boost Converter for Fuel Cell Applications  

Directory of Open Access Journals (Sweden)

Full Text Available Fuel cell is one of the promising technologies for distributed generation. For designing high efficiency fuel cell power systems, a suitable DC-DC converter is required. Among the various topologies, interleaved converters using switched capacitor are considered as a better solution for fuel cell systems due to high conversion efficiency. The objective of the paper is to design and implement a high gain interleaved converter using switched capacitors for fuel cell systems. In the proposed interleaved converter, the front end inductors are magnetically cross-coupled to improve the electrical performance and reduce the weight and size. Also, switched capacitors are used to improve the voltage gain of the converter. The proposed converter has been performed. Simulation study of interleaved converter using switched capacitors interfaced with fuel cells has been studied using Matlab/Simulink. A prototype has been developed to verify the simulation results.

R. Seyezhai

2013-11-01

332

High Efficiency Boost Converter with Three State Switching Cell  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The boost converter with the three-state switching cell seems to be a good candidate for a dc-dc stage for non-isolated generators based on alternative energy sources. It provides a high voltage gain, a reduced voltage stress on transistors and limited input current ripples. In this paper the focus is on performance improvement of this type of the converter. Use of foil windings helps to reduce conduction losses in magnetic components and to reduce size of these components. Also it has been d...

Klimczak, Pawel; Munk-nielsen, Stig

2010-01-01

333

Designing and Tuning of PI Controller for Flyback Converter  

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This paper aims at designing of an optimized controller for isolated DC-DC Flyback converter for constant voltage applications. The Flyback converter can both step up and step-down the input voltage, while maintaining the same polarity and the same ground reference for the input and output. MOSFETs are used as a switching device in low power and high frequency switching applications. It may be noted that, as the turn-on and turn-off time of MOSFETs are lower as compared to other switching dev...

Abhinav Dogra; Kanchan Pal

2014-01-01

334

Model of Bi-directional Flyback Converter for Hybrid AC/DC Distribution System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this article, a simulation model and concept of two switch bi-directional isolated DC/DC converter is presented. Converter is based on flyback converter type. Also control method for voltage regulation with bi-directional power transfer is presented. Target application of the proposed converter was selected to be a hybrid AC/DC distribution system concept of which was briefly described. The requirement of galvanic isolation in the hybrid AC/DC concept comes from use of shared neutral wire;...

Riku Pasonen

2013-01-01

335

A Multilevel Inverter For Synchronizing The Grid With Renewable Energy Sources By Implementing Battery Cum Dc-Dc Conerter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract-There is an increasing demand of power and load shedding is preferred as a solution. An interruption for a few cycles of power supply results in loss of data, mal functioning of various sensitive equipments. A model is developed to provide uninterrupted power supply to the consumers in the event of failure of the main input source. The different modes of operation that has been developed are normal, back-up and charging. The output of the integrated flyback converter is given to the ...

Karunya Christobal Lydia. S; Shanmugasundari. A; Anandhi.Y

2014-01-01

336

Modeling of asymmetrical boost converters  

Directory of Open Access Journals (Sweden)

Full Text Available The asymmetrical interleaved dual boost (AIDB is a fifth-order DC/DC converter designed to interface photovoltaic (PV panels. The AIDB produces small current harmonics to the PV panels, reducing the power losses caused by the converter operation. Moreover, the AIDB provides a large voltage conversion ratio, which is required to step-up the PV voltage to the large dc-link voltage used in grid-connected inverters. To reject irradiance and load disturbances, the AIDB must be operated in a closed-loop and a dynamic model is required. Given that the AIDB converter operates in Discontinuous Conduction Mode (DCM, classical modeling approaches based on Continuous Conduction Mode (CCM are not valid. Moreover, classical DCM modeling techniques are not suitable for the AIDB converter. Therefore, this paper develops a novel mathematical model for the AIDB converter, which is suitable for control-pur-poses. The proposed model is based on the calculation of a diode current that is typically disregarded. Moreover, because the traditional correction to the second duty cycle reported in literature is not effective, a new equation is designed. The model accuracy is contrasted with circuital simulations in time and frequency domains, obtaining satisfactory results. Finally, the usefulness of the model in control applications is illustrated with an application example.

Eliana Isabel Arango Zuluaga

2014-03-01

337

DESIGN OF BUCK-BOOST CONVERTER FOR SUPER-CAPACITOR  

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An efficent storage of energy in hybrid drives is still an important issue. In most solutions, the batteries are used. A high-capacitance capacitors, also called super-capacitor, are often used as an intermediate unit between the batteries and the drive. Because of their high dynamics they are very useful in acceleration regime when a peak of energy is required. For implementation in combination with electric motor it is necessary to adjust voltage level of super-capacitor to the driving vol...

Hari, Jernej

2011-01-01

338

A TEG Efficiency Booster with Buck-Boost Conversion  

Science.gov (United States)

A thermoelectric generator (TEG) efficiency booster with buck-boost conversion and power management is proposed as a TEG battery power conditioner suitable for a wide TEG output voltage range. An inverse-coupled inductor is employed in the buck-boost converter, which is used to achieve smooth current with low ripple on both the TEG and battery sides. Furthermore, benefiting from the magnetic flux counteraction of the two windings on the coupled inductor, the core size and power losses of the filter inductor are reduced, which can achieve both high efficiency and high power density. A power management strategy is proposed for this power conditioning system, which involves maximum power point tracking (MPPT), battery voltage control, and battery current control. A control method is employed to ensure smooth switching among different working modes. A modified MPPT control algorithm with improved dynamic and steady-state characteristics is presented and applied to the TEG battery power conditioning system to maximize energy harvesting. A 500-W prototype has been built, and experimental tests carried out on it. The power efficiency of the prototype at full load is higher than 96%, and peak efficiency of 99% is attained.

Wu, Hongfei; Sun, Kai; Zhang, Junjun; Xing, Yan

2013-07-01

339

A Standalone Solar Photovoltaic Power Generation using Cuk Converter and Single Phase Inverter  

Science.gov (United States)

In this paper, a standalone solar photovoltaic (SPV) power generating system is designed and modeled using a Cuk dc-dc converter and a single phase voltage source inverter (VSI). In this system, a dc-dc boost converter boosts a low voltage of a PV array to charge a battery at 24 V using a maximum power point tracking control algorithm. To step up a 24 V battery voltage to 360 V dc, a high frequency transformer based isolated dc-dc Cuk converter is used to reduce size, weight and losses. The dc voltage of 360 V is fed to a single phase VSI with unipolar switching to achieve a 230 Vrms, 50 Hz ac. The main objectives of this investigation are on efficiency improvement, reduction in cost, weight and size of the system and to provide an uninterruptible power to remotely located consumers. The complete SPV system is designed and it is modeled in MATLAB/Simulink. The simulated results are presented to demonstrate its satisfactory performance for validating the proposed design and control algorithm.

Verma, A. K.; Singh, B.; Kaushika, S. C.

2013-03-01

340

Multi-megawatt inverter/converter technology for space power applications  

Science.gov (United States)

Large power conditioning mass reductions will be required to enable megawatt power systems envisioned by the Strategic Defense Initiative, the Air Force, and NASA. Phase 1 of a proposed two phase interagency program has been completed to develop an 0.1 kg/kW DC/DC converter technology base for these future space applications. Three contractors, Hughes, General Electric (GE), and Maxwell were Phase 1 contractors in a competitive program to develop a megawatt lightweight DC/DC converter. Researchers at NASA Lewis Research Center and the University of Wisconsin also investigated technology in topology and control. All three contractors, as well as the University of Wisconsin, concluded at the end of the Phase 1 study, which included some critical laboratory work, that 0.1-kg/kW megawatt DC/DC converters can be built. This is an order of magnitude lower specific weight than is presently available. A brief description of each of the concepts used to meet the ambitious goals of this program are presented.

Myers, Ira T.; Baumann, Eric D.; Kraus, Robert; Hammoud, Ahmad N.

1992-01-01

 
 
 
 
341

A Multilevel Inverter For Synchronizing The Grid With Renewable Energy Sources By Implementing Battery Cum Dc-Dc Conerter  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract-There is an increasing demand of power and load shedding is preferred as a solution. An interruption for a few cycles of power supply results in loss of data, mal functioning of various sensitive equipments. A model is developed to provide uninterrupted power supply to the consumers in the event of failure of the main input source. The different modes of operation that has been developed are normal, back-up and charging. The output of the integrated flyback converter is given to the multilevel inverter. A cascaded H-bridge multilevel inverter is implemented using a single DC power source and capacitors. A standard cascaded multilevel inverter requires ‘n’ DC sources for ‘2n + 1’ levels. Without requiring transformers, the scheme proposed allows the use of a single DC power source (e.g., a battery, a fuel cell stack or photo voltaic panel with the remaining n?1 DC sources being capacitors. The DC voltage level of the capacitors can be maintained simultaneously and a fundamental frequency switching pattern can be chosen to produce a nearly sinusoidal output. The number of levels is increased up to fifteen by adding six bidirectional switches to a H-bridge inverter. The main objectives are to improve the power quality by reducing the total harmonic distortion to a very low value and the reduction of the per unit cost of electricity.

Karunya Christobal Lydia. S

2014-05-01

342

A new configuration for multilevel converters with diode clamped topology  

DEFF Research Database (Denmark)

Due to the increased use of renewable energy and power elctronic applications, more multilevel converters (MLC) are developed. A Neutral Point Clamped (NPC) inverter is one of the most used multilevel topologies for wind turbine (WT) and photovoltaic (PV) applications. One of the most crucial points in this type of converter is dc-voltage control. In this paper, a novel multi output dc-dc converter connected to a diode clamped topology is presented. This converter, for a given duty cycles, is able to regulate the capacitor voltage to provide an appropriate input voltage for NPC regardless of load changes which can avoid neutral point balancing problem in such converters. In addition, the presented topology is suitable for renewable energy systems to boost the low rectified output-voltage. In order to verify the proposed topology, steady state analysis, modelling and simulations are carried out.

Nami, A.; Zare, F.

2008-01-01

343

An Innovative Reconfigurable Integrated Converter Topology Suitable for Distributed Generation  

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Full Text Available The electricity market and environmental concerns, with wide utilization of renewable sources, have improved the diffusion of distributed generation units changing the operations of distribution grids from passive networks to microgrids. A microgrid includes a cluster of electrical loads, energy storage devices and microsources, which provide both power and heat to their local area. A microgrid has usually one connection point to the utility grid through power electronic converters placed at customers’ sites. This paper analyses a Reconfigurable Integrated Converter (RIC used for a domestic microgrid with inputs from the AC mains and photovoltaic arrays, and two DC outputs at different voltage levels. A RIC as a dual-boost DC-DC converter is proposed, modelled and analysed in the paper. The advantages of such a topology in comparison with traditional boost converters are outlined. Reported simulations results give evidence on the controllability of this converter and the capability of achieving the desired voltage outputs with reduced ripple.

Renato Rizzo

2012-09-01

344

Power Quality Improvement in PMBLDCM Drive using PFC SEPIC Converter for Air Conditioner.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, an improved power quality converter employing Single Ended Primary Inductor (SEPIC) converter topology is used to feed a permanent magnet brushless DC motor (PMBLDCM) drive. Normally, the PMBLDCM drive has a three-phase voltage source inverter (VSI) and a PMBLDCM which is fed from single-phase AC mains through a diode bridge rectifier (DBR). In this proposed system a SEPIC DC-DC converter is used after the DBR and it performs power factor correction (PFC) at input AC mains and ...

Athiyaman S; Prakasam K

2013-01-01

345

Performance Analysis of BLDC Motor Using Basic Switching Converters  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper a comparative study of CSI fed BLDC motor using Boost and Buck Converter are presented. Traditionally BLDC motor drives are fed by Voltage Source Inverters (VSI. Current Source Inverters (CSI on the other hand does not require the huge DC link capacitor thereby reducing the cost and losses in the system. The large value of the inductor can be replaced using suitable Boost and Buck converter. In this paper a basic structure of a DC boost converter and a basic structure of a DC buck converter are proposed in PSIM to provide the nominal power to BLDC motor from a fixed DC source and to control the speed of the system. The effectiveness of proposed system is validated by simulation results.

B. Das,

2012-12-01

346

Performance Analysis of BLDC Motor Using Basic Switching Converters  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper a comparative study of CSI fed BLDC motor using Boost and Buck Converter are presented. Traditionally BLDC motor drives are fed by Voltage Source Inverters (VSI). Current Source Inverters (CSI) on the other hand does not require the huge DC link capacitor thereby reducing the cost and losses in the system. The large value of the inductor can be replaced using suitable Boost and Buck converter. In this paper a basic structure of a DC boost converter and a basic structure of a DC ...

B. Das,; S. Chakraborty,; Chakraborti, A.; P. Rn. Kasari,

2012-01-01

347

Active converter based on the VIENNA rectifier topology interfacing a three-phase generator to a DC-bus  

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AC-DC converters find application in every day life as a front-end to DC-DC and DC-AC converters. Active three-phase converters shape the three-phase input current to be sinusoidal and to be in-phase with the input voltage, as well as to provide a steady DC output voltage. This thesis investigates various active three-phase rectifier and control topologies and identifies a rectifier and control topology most suitable for use in converting a variable voltage variable frequency generator out...

Visser, Jacobus Hendrik

2007-01-01

348

Designing and Tuning of PI Controller for Flyback Converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper aims at designing of an optimized controller for isolated DC-DC Flyback converter for constant voltage applications. The Flyback converter can both step up and step-down the input voltage, while maintaining the same polarity and the same ground reference for the input and output. MOSFETs are used as a switching device in low power and high frequency switching applications. It may be noted that, as the turn-on and turn-off time of MOSFETs are lower as compared to other switching devices, which reduces the switching losses. High frequency operation of MOSFET reduced size of filters components. These converters are now being used for various applications, such as Switched Mode Power Supply (SMPS etc. The paper attempts to present designing and tuning of Flyback converters for constant voltage output.

Abhinav Dogra

2014-07-01

349

A New Asymmetrical Current-fed Converter with Voltage Lifting  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a new zero voltage switching current-fed DC-DC converter with high voltage gain. In this converter all switches (main and auxiliary turn on under zero voltage switching and turn off under almost zero voltage switching due to snubber capacitor. Furthermore, the voltage spike across the main switch due to leakage inductance of forward transformer is absorbed. The flyback transformer which is connected to the output in series causes to high voltage gain and less voltage stress on the power devices. Considering high efficiency and voltage gain of this converter, it is suitable for green generated systems such as fuel cells or photovoltaic systems. The presented experimental results verify the integrity of the proposed converter.

DELSHAD, M.

2011-05-01

350

ANALYSIS OF PHOTOVOLTAIC CELLS WITH CLOSED LOOP BOOST CONVERTER  

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Full Text Available The Conventional sources of energy are rapidly depleting and cost of power has been escalating day by day. Thus an alternative renewable source of energy has become a vital necessity. Photovoltaic system is one of the most promising renewable sources of energy. Its ability to produce power by directly converting solar energy has led to tremendous surge in its demand. The output power generated by it is very less but can be increased by interfacing it with boost converter. Therefore we have proposed a model of Photovoltaic array interfaced with closed loop dc-dc boost converter which considerably steps up the output voltage which could meet the demand of power. In this paper the various characteristics of PV cells and design parameters of boost converter have been discussed in detail. The results and graphs of simulink and hardware model have been compared and discussed.

Moumi Pandit

2013-03-01

351

Analysis of current-bidirectional buck-boost based switch-mode audio amplifier  

DEFF Research Database (Denmark)

The following studdy was carried out in order to assses quantitatively the performannce of the buck--boost converter whhen used as swiitch-mode audio amplifier. It comprises of, to beggin with, the de limitation of design criteria bassed on the state of-the-art solution, which is based in a differential mode buckbased amplifier with a boost converter as power supply. The averaged switch modelling of the differential mode current bidirectional topology is also used, in order to analyze the steady state and frequency-wise behaviour of this converter and parameterize it to meet the design criteria. Next, several piecewise-linear siimulation resultss are shown with detail enough to emphasize the features of the converter. A simple prototype is implemented to verify the main predicted features. Presently no previous publicat ion could be found containing a thorough analysis of this topology in such configuration when applied for audio.

Bolten Maizonave, Gert; Andersen, Michael A. E.

2011-01-01

352

Progress on the 140 KV, 10 Megawatt Peak, 1 Megawatt Average Polyphase Quasi-Resonant Bridge, Boost Converter/Modulator for the Spallation Neutron Source (SNS) Klystron Power System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper describes electrical design and operational characteristics of a zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three "H-Bridge" IGBT switching networks are used to generate the polyphas...

Reass, William A.; Doss, James D.; Gribble, Robert F.; Lynch, Michael T.; Tallerico, Paul J.

2000-01-01

353

High-Feedback Operation of Power Electronic Converters  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this review is to provide a survey of some of the most important bifurcation phenomena that one can observe in pulse-modulated converter systems when operating with high corrector gain factors. Like other systems with switching control, electronic converter systems belong to the class of piecewise-smooth dynamical systems. A characteristic feature of such systems is that the trajectory is “sewed” together from subsequent discrete parts. Moreover, the transitions between different modes of operation in response to a parameter variation are often qualitatively different from the bifurcations we know for smooth systems. The review starts with an introduction to the concept of border-collision bifurcations and also demonstrates the approach by which the full dynamics of the piecewise-linear, time-continuous system can be reduced to the dynamics of a piecewise-smooth map. We describe the main bifurcation structures that one observes in three different types of converter systems: (1 a DC/DC converter; (2 a multi-level DC/DC converter; and (3 a DC/AC converter. Our focus will be on the bifurcations by which the regular switching dynamics becomes unstable and is replaced by ergodic or resonant periodic dynamics on the surface of a two-dimensional torus. This transition occurs when the feedback gain is increased beyond a certain threshold, for instance in Electronics 2013, 2 114 order to improve the speed and accuracy of the output voltage regulation. For each of the three converter types, we discuss a number of additional bifurcation phenomena, including the formation and reconstruction of multi-layered tori and the appearance of phase-synchronized quasiperiodicity. Our numerical simulations are compared with experimentally observed waveforms.

Gennady Y. Mikhal'chenko

2013-03-01

354

Aalborg Inverter - A new type of “Buck in Buck, Boost in Boost” Grid-tied Inverter  

DEFF Research Database (Denmark)

This paper presents a new family of high efficiency DC/AC grid-tied inverter with a wide variation of input DC voltage. It is a kind of “Boost in Boost, Buck in Buck” inverter, meaning that only one power stage works at the high frequency to achieve the minimum switching loss. Furthermore, the minimum filtering inductance in the power loop is achieved to reduce the conduction power loss whether in “Boost” or “Buck” mode. In theory, it can achieve higher efficiency than other inverters under the same condition of input DC voltage. The principle of operation is fully illustrated through the analysis on the equivalent circuits of a “three-level” single-phase inverter. Simulations show it has good control performance.

Wu, Weimin; Blaabjerg, Frede

2013-01-01

355

Voltage-Sharing Converter to Supply Single-Phase Asymmetrical Four-Level Diode-Clamped Inverter With High Power Factor Loads  

DEFF Research Database (Denmark)

The output voltage quality of some of the single-phase multilevel inverters can be improved when their dc-link voltages are regulated asymmetrically. Symmetrical and asymmetrical multilevel diode-clamped inverters have the problem of dc-link capacitor voltage balancing, especially when power factor of the load is close to unity. In this paper, a new single-inductor multi-output dc/dc converter is proposed that can control the dc-link voltages of a single-phase diode-clamped inverter asymmetrically to achieve voltage quality enhancement. The circuit of the presented converter is explained and the main equations are developed. A control strategy is proposed and explained in details. To validate the versatility of the proposed combination of the suggested dc–dc converter and the asymmetrical four-level diode-clamped inverter (ADCI), simulations and experiments have been directed. It is concluded that the proposed combination of introduced multioutput dc–dc converter and single-phase ADCI is a good candidate for power conversion in residential photovoltaic (PV) utilization.

Boora, Arash A.; Nami, Alireza

2010-01-01

356

Simulation of closed loop controlled boost converter for solar installation  

Directory of Open Access Journals (Sweden)

Full Text Available With the shortage of the energy and ever increasing of the oil price, research on the renewable and green energy sources, especially the solar arrays and the fuel cells, becomes more and more important. How to achieve high stepup and high efficiency DC/DC converters is the major consideration in the renewable power applications due to the low voltage of PV arrays and fuel cells. In this paper digital simulation of closed loop controlled boost converter for solar installation is presented. Circuit models for open loop and closed loop controlled systems are developed using the blocks of simulink. The simulation results are compared with the theoretical results. This converter has advantages like improved power factor, fast response and reduced hardware. .

Kalirasu Athimulam

2010-01-01

357

The application of standardized control and interface circuits to three dc to dc power converters.  

Science.gov (United States)

Standardized control and interface circuits were applied to the three most commonly used dc to dc converters: the buck-boost converter, the series-switching buck regulator, and the pulse-modulated parallel inverter. The two-loop ASDTIC regulation control concept was implemented by using a common analog control signal processor and a novel digital control signal processor. This resulted in control circuit standardization and superior static and dynamic performance of the three dc-to-dc converters. Power components stress control, through active peak current limiting and recovery of switching losses, was applied to enhance reliability and converter efficiency.

Yu, Y.; Biess, J. J.; Schoenfeld, A. D.; Lalli, V. R.

1973-01-01

358

The State Space Average Model of Buck- Boost Switching Regulator Including all of The System Uncertainties  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper a complete state-space average model for the buck-boost switching regulators is presented. The presented model includes the most of the regulator’s parameters and uncertainties. In modeling, the load current is assumed to be unknown, and it is assumed that the inductor, capacitor, diode and regulator active switch are non ideal and they have a resistance in conduction condition. Some other non ideal effects look like voltage drop of conduction mode of the diode and active switch are also considered. This model can be used to design a precise and robust controller that can satisfy stability andperformance conditions of the buck-boost regulator. Also the effects of the boost parameters on the performance of the regulator can be shown easily with this model. After presenting the complete model,the buck-boost converter Benchmark circuit is simulated in PSpice and its results are compared with our model simulation results in MATLAB. The results show the merit of our model.

Mohammad Reza Modabbernia

2013-02-01

359

Cross Voltage Control with Inner Hysteresis Current Control for Multi-output Boost Converter  

DEFF Research Database (Denmark)

Multi-output boost (MOB) converter is a novel DC-DC converter unlike the regular boost converter, has the ability to share its total output voltage and to have different series output voltage from a given duty cycle for low and high power applications. In this paper, discrete voltage control with inner hysteresis current control loop has been proposed to keep the simplicity of the control law for the double-output MOB converter, which can be implemented by a combination of analogue and logical ICs or simple microcontroller to constrain the output voltages of MOB converter at their reference voltages against variation in load or input voltage. The salient features of the proposed control strategy are simplicity of implementation and ease to extend to multiple outputs in the MOB converter. Simulation and experimental results are presented to show the validity of control strategy.

Nami, Alireza; Zare, Firuz

2009-01-01

360

A Self-Oscillating Control Scheme for a Boost Converter Providing a Controlled Output Current  

DEFF Research Database (Denmark)

Most switched mode power supplies provide a regulated voltage at their output. However, there are applications requiring a controlled current. Among others are battery chargers, test equipment for converters driven by solar cells, and LED drivers. This paper describes a dc–dc power converter realizing such a current source. The converter is based on a boost converter, supplied by a voltage source and acting as a current source. The boost converter can increase the output voltage above the input voltage. The converter provides a high control bandwidth based on a self-oscillating current loop. As additional practical features, soft start and output overvoltage limitation are included and described in this paper. The modulator, the control, and the power stage are described in detail and verified by the experiment.

Knott, Arnold; Pfaffinger, Gerhard R.

2011-01-01

 
 
 
 
361

High Frequency Soft Switching Of PWM Boost Converter Using Auxiliary Resonant Circuit  

Directory of Open Access Journals (Sweden)

Full Text Available This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequency of PWM converters is increased its switching losses and conduction losses also increases. This restricts the use of PWM technique. New Zero Voltage Transition-Zero Current Transition (ZVT-ZCT PWM converter equipped with the snubber provides the most desirable features of both ZVT and ZCT converters presented previously. Moreover all semiconductors devices operate with soft switching and hence losses are reduced.

C. P. Sai Kiran

2014-10-01

362

Design, Simulation and Hardware Implementation of a Multi Device Interleaved Boost Converter for Fuel Cell Applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the analysis and implementation of a two-phase  Multi Device Interleaved  Boost Converter (MDIBC.  Among the various DC-DC  topologies, Multi device Interleaved converter is considered as a better solution for fuel cell  hybrid vehicles as it reduces the  input current ripple,  output voltage ripple and the size of passive components. Detailed analysis has been done to investigate the benefits of Multi device Interleaved boost converter by comparing  it with the conventional   Interleaved boost converter topology. Moreover, in this paper, power loss analysis (switching loss, conduction loss, inductor loss of the proposed converter has been performed. Simulation study of Multi device interleaved converter has been studied using MATLAB/SIMULINK. Hardware prototype is built to validate the results.

R. Seyezhai

2014-05-01

363

Three Phase Six-Switch PWM Buck Rectifier with Power Factor Improvement  

DEFF Research Database (Denmark)

Conventional Phase Controlled Rectifier injects low order current harmonics into the AC mains. Large size filtering components are required to attenuate these harmonics. In this paper, Three Phase Six-Switch PWM Buck Rectifier[1] is presented which operates at nearly unity power factor and provides variable output voltage. Small size energy storing components are required depending upon switching frequency. MATLAB simulation is performed and modified Sinusoidal Pulse Width Modulation(SPWM) switching technique is used in 3kW prototype converter to demonstrate low input current THD, nearly unity displacement factor, well regulated output voltage and reduced switching losses compared to conventional SPWM.

Zafar Ullah Khan, M; Mohsin Naveed, M.

2013-01-01

364

Three phase six-switch PWM buck rectifier with power factor improvement  

International Nuclear Information System (INIS)

Conventional Phase Controlled Rectifier injects low order current harmonics into the AC mains. Large size filtering components are required to attenuate these harmonics. In this paper, three phase six-switch PWM buck rectifier is presented which operates at nearly unity power factor and provides variable output voltage. Small size energy storing components are required depending upon switching frequency. MATLAB simulation is performed and modified Sinusoidal Pulse Width Modulation (SPWM) switching technique is used in 3kW prototype converter to demonstrate low input current THD, nearly unity displacement factor, well regulated output voltage and reduced switching losses compared to conventional SPWM.

365

Utilization of Nonlinear Converters for Audio Amplification  

DEFF Research Database (Denmark)

Class D ampliers ts the automotive demands quite well. The traditional buck-based amplier has reduced both the cost and size of ampliers. However the buck topology is not without its limitations. The maximum peak AC output voltage produced by the power stage is only equal the supply voltage. The introduction of non-linear converters for audio amplication defeats this limitation. A Cuk converter, designed to deliver an AC peak output voltage twice the supply voltage, is presented in this paper. A 3V prototype has been developed to prove the concept. The prototype shows that it is possible to achieve an peak AC output voltage twice the supply voltage but also reveals some of the major obstacles and challenges which is also discussed.

Iversen, Niels; Birch, Thomas

2012-01-01

366

Power Quality Improvement in Bridgeless Ac-Dc Converter Based Multi-output Switched Mode Power Supply  

Science.gov (United States)

Computer power supplies are required to have multiple isolated regulated dc voltages with low ripple content and high input power factor at the utility interface. A dc-dc converter is used for obtaining these isolated multi-output dc voltages with excellent regulation. In this paper, a non-isolated ac-dc converter is proposed as the first stage converter to obtain a regulated dc output rather than using a simple uncontrolled diode bridge rectifier at the front end. A dc-dc converter is used at the second stage that has a high frequency transformer with multiple secondary windings to obtain different dc voltage levels at the output. The proposed bridgeless converter based power supply is designed using fundamental design equations, and different component values are calculated. Extensive simulations are carried out to demonstrate the improved performance of the proposed bridgeless converter based multi-output computer power supply at varying source voltages and load conditions. Experimental validation of the power supply is carried on a developed hardware prototype, and the test results are compared with the simulated performance for design verification.

Singh, Shihka; Singh, Bhim; Bhuvaneswari, G.; Bist, Vashist

2014-12-01

367

Modeling the Chain of Conversion for a PV System  

Directory of Open Access Journals (Sweden)

Full Text Available In this work, we conduct a study of modeling and simulation of a system in the context of renewable energy in general, and solar system “photovoltaic” in particular; also, the optimizing system adapted by DC-DC converters static. Then the influence of temperature and irradiance on the optimal parameters (Power of MPP, VMPP, ... of a solar system is analyzed in a way to operate a PV generator at its maximum power. This system includes a photovoltaic generator, “Boost & Buck”, converter and a load. Modeling and simulation system (solar panel, DC-DC converter command and load is obtained through Matlab-Simulink software.

Mohammed El Alami

2014-10-01

368

Fuzzy Controller Based Switched Boost Converter with Reduced Harmonics for Micro Grid Application  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Z source converter is the improved version of Voltage Source Inverter (VSI) which utilizes shoot through state of the switches and can be operated in both buck and boost mode of operation. The major drawbacks of Z Source Converter (ZSC) is the high cost, more space and not suitable for lower power applications. In order to overcome these disadvantages, Switched Boost Converter (SBC) is proposed. The proposed converter overcomes the limitations of the conventional ZSC such as lower cost, compa...

Balasubramanian, R.; Parkavi Karthirvelu, K.; Divya, N.; Rengarajan Amirtharajan; Palani, S.

2014-01-01

369

Primary Paralleled Isolated Boost Converter with Extended Operating Voltage Range  

DEFF Research Database (Denmark)

Applications requiring wide input and output voltage range cannot often be satisfied by using buck or boost derived topologies. Primary paralleled isolated boost converter (PPIBC) [1]-[2] is a high efficiency boost derived topology. This paper proposes a new operation mode for extending the input and output voltage range in PPIBC. The proposed solution does not modify PPIBC power stage, the converter gain is modified instead by short circuiting one of the paralleled connected primary windings present in this topology.

Hernandez Botella, Juan Carlos; Sen, Gökhan

2012-01-01

370

AC-AC Multilevel Converter Based Wind Energy System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract:As power consumption of portable electronic equipment rapidly increases; the need of chargers using fuel cell which has higher energy density than that of secondary battery is raised. Most chargers developed so far are mainly buck-type converters, however, if fuel cell is used the battery should be charged with an increased voltage level through boost-type converter. In addition, unlike resistive load if batteries are controlled by general method, they induce large ripple current and...

Suresh D, Jaiganesh K.

2013-01-01

371

Control of the Portable Fuel Cell Charger Using CUK Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract:As power consumption of portable electronic equipment rapidly increases; the need of chargers using fuel cell which has higher energy density than that of secondary battery is raised. Most chargers developed so far are mainly buck-type converters, however, if fuel cell is used the battery should be charged with an increased voltage level through boost-type converter. In addition, unlike resistive load if batteries are controlled by general method, they induce large ripple current and...

Tae-hoon Kim, Nguyen Sang

2013-01-01

372

Low-Voltage Direct AC-DC Boost Converter for Microgenerator Based Energy Harvesting  

Directory of Open Access Journals (Sweden)

Full Text Available The conventional power electronic converters used in the microgenerator based energy harvesting applications have two stages: a diode bridge rectifier and a dc-dc conveter. But it is less efficient and cant be used for electromagnetic microgenerators, as the diode bridge rectification is not normally feasible due to extreme low output voltage of the microgenerators. In this paper a direct ac-dc power electronic converter topology is proposed for efficient and maximum energy harvesting from low voltage microgenerators. The single stage ac-to-dc power conversion is achieved by utilizing the bidirectional conduction capability of MOSFETs. A suitable startup circuit,auxiliary dc supply circuit and a control circuit is proposed for the implementation of the converter.The proposed topology is simulated using LTspice and the results are presented to verify the operation of the converter and proposed auxilliary circuit.

ANOOP D NATH

2013-03-01

373

Analysis of Single phase inverter with Boost Converter and Photovoltaic module  

Directory of Open Access Journals (Sweden)

Full Text Available Now a day’s renewable energy like solar, wind becomes very popular. To convert solar energy into electrical energy inverter is an one of the main components. The performance of inverter is different for different pulse width modulation techniques. In this project a single phase inverter is interfaced with photovoltaic module and Boost converter. The main objective of this project is to analyze a single phase inverter for different pulse width modulation techniques like Sine Triangle Pulse Width Modulation, Bus Clamping Pulse Width Modulation technique. Also different DC-DC converter has been designed and simulated. Boost converter is considered to boosting of photovoltaic voltage. After analysis it has been observed that the bus clamping pulse width modulation technique is better as compared to conventional Sine triangle pulse width modulation technique in respect to load current ripple.

Lipika Nanda

2014-07-01

374

High Voltage Bi-directional Flyback Converter for Capacitive Actuator  

DEFF Research Database (Denmark)

This paper presents a high voltage DC-DC converter topology for bi-directional energy transfer between a low voltage DC source and a high voltage capacitive load. The topology is a bi-directional flyback converter with variable switching frequency control during the charge mode, and constant switching frequency control during the discharge mode. The converter is capable of charging the capacitive load from 24 V DC source to 2.5 kV, and discharges it to 0 V. The flyback converter has been analyzed in detail during both charge and discharge modes, by considering all the parasitic elements in the converter, including the most dominating parameters of the high voltage transformer viz., self-capacitance and leakage inductance. The specific capacitive load for this converter is a dielectric electro active polymer (DEAP) actuator, which can be used as an effective replacement for conventional actuators in a number of applications. In this paper, the discharging energy efficiency definition is introduced. The proposed converter has been experimentally tested with the film capacitive load and the DEAP actuator, and the experimental results are shown together with the efficiency measurements.

Thummala, Prasanth; Zhang, Zhe

2013-01-01

375

PERFORMANCE ANALYSIS OF 2D CONVERTER BY COMBINING SR & KY CONVERTERS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Most of the portable equipments use battery as power source. The increasing use of low voltage portable devices and growing requirements of functionalities embedded into such devices. Thus an efficient power management technique is needed for longer battery life for them. Highly variable nature of batteries systems often require supply voltages to be both higher and lower than the battery. This is most efficiently generated by a buck-boost switching converter. But here the con...

Manoj Kumar, V.; Sarma, G. V. S. S. N. S.

2014-01-01

376

Component-Minimized Buck-Boost Voltage Source Inverters  

DEFF Research Database (Denmark)

This paper presents the design of buck-boost B4 inverters that can be derived from either ?uk- or SEPIC-derived buck-boost B6 inverters. Unlike traditional inverters, the integration of front-end voltage boost circuitry and inverter circuitry allows it to perform buck-boost voltage inversion. In order to form a distinct neutral potential in the corresponding voltage boost circuitry for correct B4 inverter operation, necessary modifications are derived step by step. The resulted dc networks with symmetrical placement of passive components allow complete charging and equal energy distribution between capacitors. Modulation wise, the proposed buck-boost B4 inverters can be controlled using a carefully designed carrier-based pulse-width modulation (PWM) scheme that will always ensure balanced threephase outputs as desired, while simultaneously achieving minimal voltage stress across semiconductors. Besides the advantage of reduced active components, buck-boost B4 inverters use a little more passive components when compared with buck-boost B6 inverters, which would allow a selectable tradeoff in practice. Moreover, analysis for discontinuous conduction mode of inductor current reveals the additional voltage relationship between dc input and ac output which is beyond the expectation when continuous inductor current is assumed. These theoretical findings, together with the inverter practicality, have been confirmed in Matlab/PLECS simulations and  experimentally using laboratory implemented inverter prototypes.

Gao, F.; Loh, P.C.

2007-01-01

377

A contribution to the design specification of single-cell multi-resonant converters  

Science.gov (United States)

The state plane technique is used to develop a design-specification procedure that enables the designer to directly calculate the stresses on all elements of the different topologies for quasi-resonant converters. If parasitic elements are considered, multiresonant topologies are obtained. These topologies can be calculated for the design specification if the procedure for quasi-resonant topologies is adapted to this situation. A novel theoretical approach for describing the internal behavior of multiresonant converters and for visualizing the switching conditions and the points of maximum component stresses is proposed. The multiresonant switching technique combines two advantages: the lossless snubbing of both the transistor and the diode is achieved by only three reactive elements, and a controllable no-load operation is possible. This analysis procedure is well suited for calculating dc-dc converter with an output power up to several hundred watts.

Franck, F.; Schroeder, D.

378

Energy Management Converter with A Flyback Snubber Fed Drive for Hybrid Electric Vehicle  

Directory of Open Access Journals (Sweden)

Full Text Available Nowadays energy management converter for electric drives are commonly being used for electric vehicles applications, due to various advantages, such as: nearly zero emission and energy recovery during braking operation. To fulfill these requirements converters with bidirectional power flow capabilities are required to connect the battery to the dc link of the motor drive system. A hybrid electric vehicle is required to function in three different modes namely: acceleration mode, normal (steady-state mode and braking (regenerative mode. In the present work open loop and closed loop operation of bi-directional dc-dc full bridge converter with a flyback snubber feeding a dc motor and its energy recovery due to regenerative braking has been demonstrated. The simulations are carried out using Simulink/ MATLAB 7.6.0 (R2009b package.

DIVYA K.NAIR

2013-01-01

379

SiC-based High Efficiency Bidirectional Battery Converter for Smart PV Residential Systems  

DEFF Research Database (Denmark)

Smart PV inverters are essential components of future grids. Beside conventional functionalities they can communicate with the grid, supports the grid with reactive power and with active power from internal battery storage. To maximize internal consumption, a high efficiency bidirectional DC-DC converter for the battery storage is necessary, as energy will be processed twice. Realisation of the battery converter with silicon carbide (SiC) semiconductors offers many advantages compared to Silicon (Si), included higher power density and higher efficiency. In this paper the design of a simple high efficiency 3kW hard switching bidirectional converter based on normally-on SiC JFET is presented, 98.5% maximum efficiency has been obtained with the prototype and a comparison with SiC MOSFet 1st generation is performed.

Pham, Cam; Biris, Valeriu-Ciprian

2013-01-01

380

Basic MOSFET Based vs Couple-coils Boost Converters for Photovoltaic Generators  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Considering the optimization of a photovoltaic system, several studies show the advantage in the choice of a distributed structure. For such structures small power converters such as the boosts and buck converters appear as most appropriate. We have analysed the efficiency of small power boost-converters especially dedicated for photovoltaic energy conversion systems working in the middle and high voltage ranges. The setup studied is a photovoltaic generator connected to an AC grid working in...

Pierre Petit; Michel Aillerie; The Vinh Nguyen; Jean-Pierre Charles

2014-01-01

 
 
 
 
381

Royal jelly counteracts bucks' "summer infertility".  

Science.gov (United States)

Exposure of male rabbits to heat stress during summer adversely affects their fertility leading to major production losses. A total number of 24 male rabbits were randomly divided into four experimental groups exposed to temperatures ranging from a high of 32 degrees C to a low of 23 degrees C. Animals of the 2nd, 3rd and 4th group were individually orally given 200, 400, or 800 mg royal jelly (RJ)/kg body weight once a week to evaluate the ability of RJ feeding to counteract "summer infertility" in bucks and enhance their physiological status. Royal jelly treatments significantly boosted testosterone level to 133, 143 and 124% of basal, increased ejaculated volume by 36, 31 and 18%, increased seminal plasma fructose to 122, 124, and 111%, improved sperm motility by 15, 18 and 5%, increase sperm total output by 65, 63 and 35%, reduced abnormal sperm by 24, 24 and 15% and dead sperm by 27, 25 and 17% compared to the heat stressed control animals. Serum total protein, albumin and globulin increased while serum total lipids, cholesterol and triglycerides decreased with RJ treatments. Creatinine was reduced by 5, 13 and 8% and uric acid by 4, 7 and 4%, respectively for the three doses of RJ compared to control. Alkaline phosphatase has significantly increased to reach 114, 118, and 108% of heat stressed level with the three doses of RJ, indicating the occurrence of active bone deposition. Glucose level increased significantly to reach 105, 112, and 116% of heat stressed control and both calcium and phosphorus increased significantly with RJ treatments. It was concluded that royal jelly administration to heat stressed male rabbits can counteract their "summer infertility" and improve their physiological status. PMID:20538419

Elnagar, Samar A

2010-08-01

382

Matlab Simulation of Very High Frequency Resonant Converters for LED Lighting  

Directory of Open Access Journals (Sweden)

Full Text Available This Paper presents a Very High Frequency DcDC Converters are used in converting the unregulated DC input into a controlled DC output at a desired voltage level. It is been observed that from last one decade the focus on green and environmental friendly energy usage has been increased. This has lead to a large increasing in the use of Light Emitting Diodes (LED’s for lighting purpose. The bulbs are quite expensive due to both expensive LEDs and the power converter needed to supply these. Hence there is a strong demand for small, cheap and efficient power converters. In this Paper three different resonant topologies are compared and their usability is discussed. The proposed Converter for LED lighting is a resonant based high frequency Converter called as SEPIC (Single Ended Primary Inductor Converter which is advantageous compared to other type of converter topologies which is compared in this paper. The proposed Converter design provides high efficiency over a wide input and output voltage range, up-and-down voltage conversion, small size and excellent transient performance. Simulation of a 51MHz Converter with 40V input and 15V output are made. The Simulation shows possibility of achieving higher efficiency with a Power MOSFET.

Avinash.C.M*

2014-05-01

383

High-Efficiency Isolated Boost DCDC Converter for High-Power Low-Voltage Fuel-Cell Applications  

DEFF Research Database (Denmark)

A new design approach achieving very high conversion efficiency in low-voltage high-power isolated boost dc-dc converters is presented. The transformer eddy-current and proximity effects are analyzed, demonstrating that an extensive interleaving of primary and secondary windings is needed to avoid high winding losses. The analysis of transformer leakage inductance reveals that extremely low leakage inductance can be achieved, allowing stored energy to be dissipated. Power MOSFETs fully rated for repetitive avalanches allow primary-side voltage clamp circuits to be eliminated. The oversizing of the primary-switch voltage rating can thus be avoided, significantly reducing switch-conduction losses. Finally, silicon carbide rectifying diodes allow fast diode turn-off, further reducing losses. Detailed test results from a 1.5-kW full-bridge boost dc-dc converter verify the theoretical analysis and demonstrate very high conversion efficiency. The efficiency at minimum input voltage and maximum power is 96.8%. The maximum efficiency of the proposed converter is 98%.

Nymand, Morten; Andersen, Michael A. E.

2010-01-01

384

Modular Power Electronic Converters in the Power Range 1 to 10 kW  

DEFF Research Database (Denmark)

Thanks to CO2 emission reduction policies and increasing prices of fossil fuels a significant growth in field of sustainable energy sources (SES) is being observed during last decade. A government support and take-off projects in Europe and US shall ensure an increasing trend in future too. Some of SES based plants , like hydro-, geothermal-, biofuel-plants, use synchronous generators directly connected to the grid. But some other SES technologies, like fuel cell or photovoltaic, require a power electronic converter between the energy source and the load or the grid. Work presented in this thesis concentrates on dc-dc non-isolated converters suitable for high voltage gain applications, like uninterruptible power supply (UPS) and some of sustainable energy sources. A special attention is on reduction of power losses and efficiency improvements in non-isolated dc-dc step-up converters. During literature study many different non-isolated dc-dc step-up topologies were found, however not all of them are desiredfor high voltage gain applications. It’s found that converters based on an inductor and a coupled-inductor principle (a boost and a center tapped boost converters) as well as converters derived from isolated converters (a non-isolated flyback-boost, a non-isolated push-pull-boost and a non-isolated two-inductor-boost converters) are good candidates for future investigation. Analysis and comparison of selected, most promising topologies indicated that a non-isolated push-pull-boost and a non-isolated two-inductor-boost converters are the best candidates for applications requiring a high voltage gain. Design of a high efficiency converter requires a detailed knowledge and accurate prediction of power losses. For this purpose average steady-state models of selected topologies and component loss models are developed and implemented in MATLAB. Converter models base on analysis of ideal waveforms and are built-up from set of equations describing values essential for power loss calculation, e.g. average or rms current values. These data are used by component models to calculate losses in particular components. It’s important that component models use parameters from datasheets in most cases. It enables performance comparison of different topologies as well as comparison of different components. The proposed modeling approach was verified using a basic boost converter breadboard. With small modification these models may be used for design purposes, like search for optimum output power and optimum switching frequency for given topology and given MOSFETs. Using developed tools and models the converter breadboard was designed. The breadboard demonstrated a very high efficiency, comparable with present state-of-the-art isolated converters. A modular converter concept and its influence on a fuel cell converter overall efficiency were investigated too. Based on simulation and measurement results it was demonstrated that the parallel modular converter used in a fuel cell application achieves a high efficiency over wide range of the output power. Moreover, the efficiency increases while the output power decreases, which is opposite to a solid converter solution.

Klimczak, Pawel

2009-01-01

385

SINGLE-PHASE BUCK-TYPE POWER FACTOR CORRECTOR WITH LOWER HARMONIC CONTENTS IN COMPLIANCE WITH IEC 61000-3-2  

Directory of Open Access Journals (Sweden)

Full Text Available A buck-type single-phase AC to DC converter is proposed in this paper. The conventional semiconverter which uses thyristors at line frequency has a very poor power factor (PF. Therefore, the semiconverter is modified to a new converter using metal oxide semiconductor field effect transistors (MOSFETs. This new converter is operated at constant switching frequency and variable duty cycle, using a very simple control scheme in voltage follower mode to achieve almost unity PF and low total harmonic distortion (THD. The output voltage is kept constant irrespective of variaions in the line voltage. The converter is analyzed and simulated to check the validity. The line current drawn by the converter is almost sinusoidal and harmonics are within the class A and class D limits imposed by harmonic standard IEC 61000-3-2.

MAHADEV S. PATIL

2010-11-01

386

Small-Signal Analysis of Single-Phase and Three-phase DC/AC and AC/DC PWM Converters with the Frequency-Shift Technique  

DEFF Research Database (Denmark)

A systematic approach to study dc/ac and ac/dc converters without the use of synchronous transformation is proposed. The use of a frequency-shift technique allows a straightforward analysis of single-phase and three-phase systems. The study of dc/ac and of ac/dc converters is reported to the study of dc/dc converters via a 50 Hz frequency-shift. The input admittance is calculated and measured for two study examples (a three-phase active rectifier and a single-phase photovoltaic inverter). These examples show that the purpose of a well designed controller for grid-connected converters is to minimize the input admittance in order to make the grid converter more robust to grid disturbance.

Blaabjerg, Frede; Aquila, A. Dell?

2004-01-01

387

Stack and converter-integrated design for efficient residential fuel cell system  

Energy Technology Data Exchange (ETDEWEB)

The stack of a residential fuel cell power generation system has low voltage and high current output characteristics. Due to which it is difficult for the converter to achieve high efficiency. Therefore, efficiency improvement is an important issue in the converter design. And in the current references about the efficient converter design, the stack parameters are supposed to be fixed before the converter design begins. This paper first investigates the relationship between the stack parameters and the converter efficiency. Based on the theoretical derivations, a novel stack and converter integrated design scheme is proposed to improve and optimize the converter efficiency. Full bridge is widely used as the DC-DC converter topology for medium and large power range, which is also used as an example in this paper. The full bridge converter can be classified between voltage fed and current fed types depending on their input circuit. This paper first analyses and compares the efficiency of the two converter types at fixed power, when the stack operating voltage is sweeping from low to high. The results show that the efficiency trends of the two converter types are monotone and in opposite directions with one intersection. A detailed description of the stack design later in this paper proves that even with the fixed stack power, the stack parameters design can change the stack operating voltage. Therefore, the stack parameters design determines the converter efficiency and which converter is more efficient. When the more efficient converter is chosen, the stack parameters design can be further optimized to improve the specific chosen converter efficiency by changing the stack operating voltage. Finally, it is concluded that the stack and the converter integrated design contributes to the fuel cell system efficiency improvement. (author)

Wang, Yong; Zhao, Qi; Borup, U. [Danfoss Solar Inverters, Jyllandsgade 28, DK-6400 Soenderborg (Denmark); Choi, Seeyoung [Digital Appliance Division, Samsung Electronics Co., Ltd., Maetan-3Dong, Suwon, Gyeonggi (Korea)

2009-09-15

388

Control of a Stand-Alone Variable Speed Wind Energy Supply System †  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a simple control strategy for the operation of a variable speed stand-alone wind turbine with a permanent magnet synchronous generator (PMSG). The PMSG is connected to a three phase resistive load through a switch mode rectifier and a voltage source inverter. Control of the generator side converter is used to achieve maximum power extraction from the available wind power. Control of the DC-DC bidirectional buck-boost converter, which is connected between batteries bank and...

Hamada, Mohamed M.; Wahab, Mohamed A. A.; Tomonobu Senjyu; Mohamed Orabi; Hussein, Mahmoud M.

2013-01-01

389

Grid Connected Fuel Cell Powered System Using Cascaded Quasi Z Source Network  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a cascaded quasi-Z-source network based step up DC/DC converter for fuel powered system reduces the component stresses and size of the converter. This network provides voltage boost and buck functions in single stage without any additional switches by the introduction of special switching strategy. Presence of this strategy provides continuous input current on the primary side of the inverter. A voltage doubler is designed for increasing the transformer secondary side volt...

Pavithradevi, N.; Karthick, P.; Jenibha Joshi, J.; Suresh Kumar, R.

2013-01-01

390

A new DC/AC boost transformerless converter in application of photovoltaic power generation  

DEFF Research Database (Denmark)

This paper presents a new DC/AC boost transformerless converter in the applications of photovoltaic (PV) power generation. A new circuit topology of single phase full bridge power inverter with additional DC/DC boost stage is proposed. The proposed topology overcomes two commonly existing shortcomings of transformerless PV system: namely one, the voltage generated sometimes low and insufficient to fulfill the load requirement; and two, there always leakage current flowing through parasitic capacitance between PV panel and ground. This configuration helps to boost the voltage at the PV side, and then converts the DC into AC to supply the load. A special modulation technique is proposed to eliminate the leakage current which is commonly presents in PV transformerless power generation, helps to increase the system efficiency and output performance.

Wei, Mo; Loh, Poh Chiang

2011-01-01

391

Design And Implementation Of PFC CUK Converter-Based PMBLDCM Drive  

Directory of Open Access Journals (Sweden)

Full Text Available This method is used to improve the efficiency of motor drive by power factor correction. It plays an important role in energy saving during energy conversion. A cuk dc -dc converter topology reduced the power quality problems and improve the power factor at input ac mains. A three-phase voltage-source inverter is used as an electronic commutator operates the PMBLDCM drive The concept of voltage control at the dc link proportional to the desired speed of the PMBLDCM is used to control the speed of the compressor. The proposed power factor converter topology is designed, modeled and its performance is evaluated in matlab-simulink environment. The results show an improved power quality and good power factor in wide speed range of the drive. It also compares the Total Harmonic Distortion (THD of the Input AC current with PID controller in Matlab-Simulink environment.

S. Kaliappan

2014-02-01

392

5kW phase-shifted full-bridge converter with current doubler using normally-off SiC JFETs designed for 98% efficiency  

DEFF Research Database (Denmark)

In this paper a 5kW step-down converter for low-voltage high-current application is presented using normally-off SiC JFETs as high voltage power switches, operating with efficiency close to 98%. Different low voltage side rectification solutions and loss estimations are also presented. As results show higher power density and efficiency can be achieved in medium- or high-power DC-DC applications by replacing silicone power devices with SiC alternatives.

Török, Lajos; Beczkowski, Szymon

2013-01-01

393

Photovoltaic optimizer boost converters: Temperature influence and electro-thermal design  

International Nuclear Information System (INIS)

Highlights: • The influence of temperature on DC–DC converter devices properties is considered. • An electro-thermal design method for PV power optimizer converters is proposed. • The electro-thermal design method proposed is applied to DR boost and SR boost. • Efficiency results of the designed SR converter and DR converters are presented. - Abstract: Objective: Photovoltaic (PV) systems can operate in presence of not uniform working conditions caused by continuously changing temperature and irradiance values and mismatching and shadowing phenomena. The more the PV system works in these conditions, the more its energy performances are negatively affected. Distributed Maximum Power Point Tracking (DMPPT) converters are now increasingly used to overcome this problem and to improve PV applications efficiency. A DMPPT system consists in a DC–DC converters equipped with a suitable controller dedicated to the Maximum Power Point Tracking (MPPT) of a single PV module. It is arranged either inside the junction-box or in a separate box close to the PV generator. Many power optimizers are now commercially available. In spite of different adopted DC–DC converter topologies, the shared interests of DMPPT systems designers are the high efficiency and reliability values. It is worth noting that to obtain so high performances converters, electronic components have to be carefully selected between the whole commercial availability and appropriately matched together. In this scenario, an electro-thermal design methodology is proposed and a reliability study by means of the Military Handbook 217F is carried out. Method: The developed DMPPT converters design method is constituted by many steps. In fact, beginning from installation site, PV generators and load data, this process selects power optimizers commercially available devices and it verifies their electro-thermal behavior to the aim to identify a set of suitable components for DMPPT applications. Repeating this process many times, many different feasible solutions can be found. An elaboration step follows to the “optima” power optimizer recognition among the whole obtained converters. In this case, a multi-objective optimization, consisting in the maximization of the solutions European efficiency and in the minimization of their cost, is executed and all not dominated solutions with respect to at least one of the two objectives are selected. The strength of the described method is represented by accurate PV generators and optimizer devices models. In detail, in the developed models particular attention is reserved to the thermal factor and to the quantification of the temperature action on devices parameters and performances. In fact, in such multiple and continuous changing working conditions, the temperature influence on components behavior can considerably vary their properties causing the whole converter performances worsening. The other important aspect, the converter reliability, is estimated by the reliability prediction model Military Handbook 217F. Results: The proposed tool is applied to Diode Rectification (DR) boosts and Synchronous (SR) boosts design. To completely characterize the obtained solutions their efficiency, cost and reliability performances are evaluated. In detail, Pareto fronts in terms of European efficiency and cost are identified for the SR and DR cases. Among the whole not dominated solutions, a SR converter characterized by a European efficiency of 97.1% and a DR boost characterized by a European efficiency of 95.5% are chosen. Their cost is comparable and equal about to $11. Then their reliability performances are evaluated by means of the Military Handbook 217F Notice 2. The carried out analysis shows that, for the same device cost, the SR solution represents the best one if efficiency is the most critical aspect. DR boost is, instead, the optimum solution if reliability represents the tighter requirement. Conclusion: The proposed DMPPT converters methodology permits to design families of feasible power optimizers. This process is

394

Novel power electronic interface for grid-connected fuel cell power generation system  

International Nuclear Information System (INIS)

Highlights: • A fuel cell power generation system was composed of a DC–DC power converter and a DC–AC inverter. • A voltage doubler based topology was adopted to configure the DC–DC power converter. • A dual buck power converter and a full-bridge power converter were applied to the DC–AC inverter. • The DC–AC inverter outputs a five-level voltage. • The DC–AC inverter performs the functions of DC–AC power conversion and active power filter. - Abstract: A novel power electronic interface for the grid-connected fuel cell power generation system is proposed in this paper. This power electronic interface is composed of a DC–DC power converter and a DC–AC inverter. A voltage doubler based topology is adopted to configure the DC–DC power converter to perform high step-up gain for boosting the output voltage of the fuel cell to a higher voltage. Moreover, the input current ripple of the fuel cell is suppressed by controlling the DC–DC power converter. The DC–AC inverter is configured by a dual buck power converter and a full-bridge power converter to generate a five-level AC output voltage. The DC–AC inverter can perform the functions of DC–AC power conversion and active power filtration. A 1.2 kW hardware prototype is developed to verify the performance of the proposed power electronic interface for the grid-connected fuel cell power generation system. The experimental results show that the proposed power electronic interface for the grid-connected fuel cell power generation system has the expected performance

395

Compensated gain control circuit for buck regulator command charge circuit  

Science.gov (United States)

A buck regulator command charge circuit includes a compensated-gain control signal for compensating for changes in the component values in order to achieve optimal voltage regulation. The compensated-gain control circuit includes an automatic-gain control circuit for generating a variable-gain control signal. The automatic-gain control circuit is formed of a precision rectifier circuit, a filter network, an error amplifier, and an integrator circuit. 5 figs.

Barrett, D.M.

1996-11-05

396

High-frequency high-voltage high-power DC-to-DC converters  

Science.gov (United States)

A simple analysis of the current and voltage waveshapes associated with the power transistor and the power diode in an example current-or-voltage step-up (buck-boost) converter is presented. The purpose of the analysis is to provide an overview of the problems and design trade-offs which must be addressed as high-power high-voltage converters are operated at switching frequencies in the range of 100 kHz and beyond. Although the analysis focuses on the current-or-voltage step-up converter as the vehicle for discussion, the basic principles presented are applicable to other converter topologies as well.

Wilson, T. G.; Owen, H. A.; Wilson, P. M.

1982-01-01

397

Local digital control of power electronic converters in a dc microgrid based on a-priori derivation of switching surfaces  

Science.gov (United States)

In power electronic basedmicrogrids, the computational requirements needed to implement an optimized online control strategy can be prohibitive. The work presented in this dissertation proposes a generalized method of derivation of geometric manifolds in a dc microgrid that is based on the a-priori computation of the optimal reactions and trajectories for classes of events in a dc microgrid. The proposed states are the stored energies in all the energy storage elements of the dc microgrid and power flowing into them. It is anticipated that calculating a large enough set of dissimilar transient scenarios will also span many scenarios not specifically used to develop the surface. These geometric manifolds will then be used as reference surfaces in any type of controller, such as a sliding mode hysteretic controller. The presence of switched power converters in microgrids involve different control actions for different system events. The control of the switch states of the converters is essential for steady state and transient operations. A digital memory look-up based controller that uses a hysteretic sliding mode control strategy is an effective technique to generate the proper switch states for the converters. An example dcmicrogrid with three dc-dc boost converters and resistive loads is considered for this work. The geometric manifolds are successfully generated for transient events, such as step changes in the loads and the sources. The surfaces corresponding to a specific case of step change in the loads are then used as reference surfaces in an EEPROM for experimentally validating the control strategy. The required switch states corresponding to this specific transient scenario are programmed in the EEPROM as a memory table. This controls the switching of the dc-dc boost converters and drives the system states to the reference manifold. In this work, it is shown that this strategy effectively controls the system for a transient condition such as step changes in the loads for the example case.

Banerjee, Bibaswan

398

Analog Fixed Maximum Power Point Control for a PWM Step-downConverter for Water Pumping Installations  

DEFF Research Database (Denmark)

This paper describes a Fixed Maximum Power Point analog control used in a step-down Pulse Width Modulated power converter. The DC/DC converter drives a DC motor used in small water pumping installations, without any electric storage device. The power supply is provided by PV panels working around their maximum power point, with a fixed operating voltage value. The control circuit implementation is not only simple and cheap, but also robust and reliable. System protections and adjustments are also proposed. Simulations and hardware are reported in the paper for a 150W water pumping application system. The proposed Optimal Power Point fix voltage control system is analyzed in comparison to other complex controls.

Beltran, H.; Perez, E.

2009-01-01

399

Bucking the System in Wyoming: Eliminating Minimum Qualifications and Converting to a "KSA System"  

Science.gov (United States)

Minimum qualifications, such as possession of an academic degree and a required number of years of work experience, have long been staples of many higher education institutions' hiring practices. However, the University of Wyoming has found that eliminating these minimum qualifications in favor of a hiring system based on knowledge, skills and…

Seastedt, Erik

2003-01-01

400

High efficiency envelope tracking buck converter for RFPA using GaN HEMTs  

Digital Repository Infrastructure Vision for European Research (DRIVER)

—In this paper, application of a new technological solution for power switches based on Gallium Nitride and a filter design methodology for high efficiency Envelope Amplifier in RF transmitters are proposed. Comparing to Si MOSFETs, GaN HEMTs can provide higher efficiency of the Envelope Amplifier, due to better Figure Of Merit (lower product of on- resistance and gate charge). Benefits of their application were verified through the experimental results. The goal of the filter design...

Cucak, Dejana; Vasic, Miroslav; Garci?a Sua?rez, Oscar; Oliver Rami?rez, Jesu?s Angel; Alou Cervera, Pedro; Cobos Ma?rquez, Jose? Antonio

2011-01-01

 
 
 
 
401

MPPT Using Fuzzy Logic Control and Buck Converter for Photovoltaic System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a fuzzy logic control (FLC) is proposed to control the maximum power point tracking (MPPT) for a photovoltaic (PV) system. The proposed technique uses the fuzzy logic control to specify the size of incremental current in the current command of MPPT. As results indicated, the convergence time of maximum power point (MPP) of the proposed algorithm is better than that of the conventional Perturb and Observation (P&O) technique. The simulation results have been u...

C.Thulasi Priya*1,; Syed Faseeha Sheereen2; sG.Divya Srihitha3

2014-01-01

402

Maximum Power Point Tracking For Photovoltaic System by Perturb and Observe Method Using Buck Boost Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Energy, especially alternative source of energy is vital for the development of a country. In future, the world anticipates to develop more of its solar resource potential as an alternative energy source to overcome the persistent shortages and unreliability of power supply. In order to maximize the power output the system components of the photovoltaic system should be optimized. For the optimization maximum power point tracking (MPPT) is a promising technique that grid tie inverters, solar ...

M S Sivagamaundari, Dr P. Melba Mary

2013-01-01

403

Fuzzy Control of a Lead Acid Battery Charger  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, an alternative battery charging control technique based on fuzzy logic for photovoltaic (PV applications is presented. A PV module is connected to a buck type DC/DC power converter and a microcontroller based unit is used to control the lead acid battery charging voltage. The fuzzy control is used due to the simplicity of implementation, robustness and independence from the complex mathematical representation of the battery. The usefulness of this control method is confirmed by experiments.

A. DAOUD

2005-03-01

404

Fuzzy Control of a Lead Acid Battery Charger  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, an alternative battery charging control technique based on fuzzy logic for photovoltaic (PV) applications is presented. A PV module is connected to a buck type DC/DC power converter and a microcontroller based unit is used to control the lead acid battery charging voltage. The fuzzy control is used due to the simplicity of implementation, robustness and independence from the complex mathematical representation of the battery. The usefulness of this control method is confirmed b...

Daoud, A.; Midoun, A.

2005-01-01

405

Design and Control of a Multi-Functional Energy Recovery Power Accumulator Battery Pack Testing System for Electric Vehicles  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, aiming at the energy loss and harmonic problems in the conventional power accumulator battery pack testing system (PABPTS), an improved multi-functional energy recovery PABPTS (ERPABPTS) for electric vehicles (EVs) was proposed. The improved system has the functions of harmonic detection, suppression, reactive compensation and energy recovery. The ERPABPTS, which contains a bi-directional buck-boost direct current (DC)-DC converter and a bi-directional alternating current (AC)-...

Bo Long; Ji Hyoung Ryu; Shin Teak Lim; Kil To Chong

2014-01-01

406

Measurement Converter  

Science.gov (United States)

Many online calculators require a Java-capable browser. Here's one that doesn't, and will perform over 500 different unit conversions for distance, area, volume, mass, speed, temperature, pressure, energy, power, force, etc. And when you convert, say, 5 kilometers to miles, you not only get the conversion result, but a wealth of related measurements and sample conversions.

407

Derivation of linearized transfer functions for switching-mode regulations. Phase A: Current step-up and voltage step-up converters  

Science.gov (United States)

Small-signal models are derived for the power stage of the voltage step-up (boost) and the current step-up (buck) converters. The modeling covers operation in both the continuous-mmf mode and the discontinuous-mmf mode. The power stage in the regulated current step-up converter on board the Dynamics Explorer Satellite is used as an example to illustrate the procedures in obtaining the small-signal functions characterizing a regulated converter.

Wong, R. C.; Owen, H. A., Jr.; Wilson, T. G.

1981-01-01

408

Meta-axiological buck-passing account of value  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we consider an incomplete T. M. Scanlon’s meta-axiological project, analysis of the relationship between values and reasons which he referred to as the “buckpassing account of value”. We will try to show the necessity of distinguishing between the “broader” and “narrower” buck-passing conception of value, a difference that critics of the conception usually ignored. This will also show that the objection which has been defined as the „wrong kind of reason problem“ is unjustifiably expanded to the conception as a whole.

Dobrijevi? Aleksandar

2014-01-01

409

Research on a High-Efficiency LED Driving Circuit Based on Buck Topology  

Directory of Open Access Journals (Sweden)

Full Text Available A high efficiency LED(Light Emitting Diode driver based on Buck converter, which could operate under a wide AC input voltage range(85V~265V and drive a series of high power LEDs, is presented in this paper. The operation principles, power loss factors of the LED driver in this study are analyzed and discussed in detail and some effective ways to improve efficiency are proposed through system design considerations. To verify the feasibility, a laboratory prototype is also designed and tested for an LED lamp which consists of 16 LUMILEDS LEDs in series. Experimental results show that a high efficiency of 92% at I0=350mA can be achieved and the studied driver might be practical for driving high power LEDs. In the last, the overall efficiency over 90% is gained through some experiments under variable input and output voltages and verifies the validity of the designed driver.

Renbo Xu

2011-10-01

410

A Photovoltaic Power System Using a High Step-up Converter for DC Load Applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a power system using a high step-up converter for dc load applications. The high step-up converter adopts a boost converter with interleaved mode and a coupled inductor to raise its powering ability and increase its step-up voltage ratio, respectively. In order to increase conversion efficiency, an active clamp circuit is introduced into the proposed one to provide soft-switching features to reduce switching losses. Moreover, switches in the converter and active clamp circuit are integrated with a synchronous switching technique to reduce circuit complexity and component counts, resulting in a lower cost and smaller volume. A perturb and observe method is adopted to extract the maximum power from photovoltaic (PV arrays. Furthermore, a microchip associated with PWM IC is used to implement maximum power point tracking operation, voltage regulation and power management. Finally, a prototype PV power system with 400 V/6 A has been implemented for verifying the feasibility of the proposed PV power system. It is shown to be suitable for PV energy conversion applications when the duty ratios of switches in the dc/dc converter are less than 0.5.

Hung-Yuan Wang

2013-02-01

411

Thermionic converter  

International Nuclear Information System (INIS)

In thermionic converters for direct conversion of thermal into electric energy consisting of a heated emitter electrode and a collector electrode cooled by a heat pipe, the temperature of the heat pipe can be raised by influencing its cooling properties in such a way that the vapor pressure of the cesium filling the space between the electrodes is always adjusted in optimum relation to the actual emitter temperature and an optimum converter function is achieved at all operational temperatures. According to the invention, this results from the use of thermal shields which can be showed by means of bimetallic strips or from indroduction of a gas plug in the remote part of the heat pipe with respect to the electrodes. (UWI)

412

Hydrogen converters  

International Nuclear Information System (INIS)

The National Atomic Energy Commission of Argentina developed a process of 99Mo production from fission, based on irradiation of uranium aluminide targets with thermal neutrons in the RA-3 reactor of the Ezeiza Atomic Centre. These targets are afterwards dissolved in an alkaline solution, with the consequent liberation of hydrogen as the main gaseous residue. This work deals with the use of a first model of metallic converter and a later prototype of glass converter at laboratory scale, adjusted to the requirements and conditions of the specific redox process. Oxidized copper wires were used, which were reduced to elementary copper at 400 C degrees and then regenerated by oxidation with hot air. Details of the bed structure and the operation conditions are also provided. The equipment required for the assembling in cells is minimal and, taking into account the operation final temperature and the purge with nitrogen, the procedure is totally safe. Finally, the results are extrapolated for the design of a converter to be used in a hot cell. (author)

413

Wavelength Converters  

DEFF Research Database (Denmark)

After a short introduction to the different requirements to and techniques for wavelength conversion, focus is on cross-gain and cross-phase modulation in SOAs and SOA based interferometers. Aspects like jitter accumulation, regeneration and conversion to the same wavelength is discussed. It is predicted that jitter accumulation can be minimised by using a 9-10 dB ratio between the signal and CW power also assuring a high extinction ratio. Using this guideline simulations show that 20 cross-gain modulation converters can be cascaded at 10 Gbit/s with only ~20 ps of accumulated jitter and an extinction ratio of ~10 dB.The regenerative capabilities of the cross-phase converters are described and verified experimentally at 20 Gbit/s, where the noise redistribution and improvement of the signal-to-noise ratio clearly is demonstrated by controlling the input power to an EDFA. In a similar experiment at 2.5 Gbit/s, the regeneration causes a reduction of the required input power to an in-line EDFA of ~6 dB for a power penalty of 1 dB at a bit error rate of 10-9. If two converters are concatenated the power requirement is reduced ~8 dB. Obviously, the power reduction allows for longer spans between in-line EDFAs.

Kloch, Allan; Hansen, Peter Bukhave

1999-01-01

414

Determination of Glycerol Percentages for Preserving the Black Bengal Buck (Capra hircus Spermatozoa for Long Time  

Directory of Open Access Journals (Sweden)

Full Text Available The percentages of glycerol level were determined for long time buck semen preservation and the highest post-thaw motility was observed using fifty-four ejaculates, collected twice in a week from the 3 mature Black Bengal Bucks (18 from each buck. Every 6 ejaculates from each buck were preserved in liquid nitrogen with different percentages of glycerol with tris-glucose-citric acid-egg yolk media by one-step dilution method. The motility was observed in fresh semen, two hours after chilling and 24 hours after freezing. In fresh semen there was no significant variation on sperm motility either between bucks or within the buck. Two hours after chilling the sperm motility was significantly higher (P<0.01 in 7% glycerol added diluents than that of 5 and 10% glycerol. Similar results were also observed following 24 hours after freezing (P<0.01, where the highest post-thaw motility was 52%. Therefore, 7% glycerol containing media appear to be suitable for preserving the Black Bengal Buck semen for future use.

D. Biswas

2002-01-01

415

Bi-Frequency Modulated Quasi-Resonant Converters: Theory and Applications  

Science.gov (United States)

To avoid the variable frequency operation of quasi -resonant converters, many soft-switching PWM converters have been proposed, all of them require an auxiliary switch, which will increase the cost and complexity of the power supply system. In this thesis, a new kind of technique for quasi -resonant converters has been proposed, which is called the bi-frequency modulation technique. By operating the quasi-resonant converters at two switching frequencies, this technique enables quasi-resonant converters to achieve the soft-switching, at fixed switching frequencies, without an auxiliary switch. The steady-state analysis of four commonly used quasi-resonant converters, namely, ZVS buck, ZCS buck, ZVS boost, and ZCS boost converter has been presented. Using the concepts of equivalent sources, equivalent sinks, and resonant tank, the large signal models of these four quasi -resonant converters were developed. Based on these models, the steady-state control characteristics of BFM ZVS buck, BFM ZCS buck, BFM ZVS boost, and BFM ZCS boost converter have been derived. The functional block and design consideration of the bi-frequency controller were presented, and one of the implementations of the bi-frequency controller was given. A complete design example has been presented. Both computer simulations and experimental results have verified that the bi-frequency modulated quasi-resonant converters can achieve soft-switching, at fixed switching frequencies, without an auxiliary switch. One of the application of bi-frequency modulation technique is for EMI reduction. The basic principle of using BFM technique for EMI reduction was introduced. Based on the spectral analysis, the EMI performances of the PWM, variable-frequency, and bi-frequency modulated control signals was evaluated, and the BFM control signals show the lowest EMI emission. The bi-frequency modulated technique has also been applied to the power factor correction. A BFM zero -current switching boost converter has been designed for the power factor correction, and the simulation results show that the power factor has been improved.

Zhang, Yuefeng

1995-01-01

416

AC-AC Multilevel Converter Based Wind Energy System  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract:As power consumption of portable electronic equipment rapidly increases; the need of chargers using fuel cell which has higher energy density than that of secondary battery is raised. Most chargers developed so far are mainly buck-type converters, however, if fuel cell is used the battery should be charged with an increased voltage level through boost-type converter. In addition, unlike resistive load if batteries are controlled by general method, they induce large ripple current and have bad influence on the efficiency and life cycle of the batteries. Therefore, the selection of appropriate topology and control method is very important. In this paper a method of control for portable fuel-cell charger using small PEM (Proton Exchange Membrane fuel cell stack and Cuk converter is proposed and the feasibility of it is verified through the experiments.

SURESH.D, JAIGANESH.K, DURAISWAMY.K

2013-05-01

417

Control of the Portable Fuel Cell Charger Using CUK Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract:As power consumption of portable electronic equipment rapidly increases; the need of chargers using fuel cell which has higher energy density than that of secondary battery is raised. Most chargers developed so far are mainly buck-type converters, however, if fuel cell is used the battery should be charged with an increased voltage level through boost-type converter. In addition, unlike resistive load if batteries are controlled by general method, they induce large ripple current and have bad influence on the efficiency and life cycle of the batteries. Therefore, the selection of appropriate topology and control method is very important. In this paper a method of control for portable fuel-cell charger using small PEM (Proton Exchange Membrane fuel cell stack and Cuk converter is proposed and the feasibility of it is verified through the experiments.

TAE-HOON KIM, NGUYEN VAN SANG, WOOJIN CHOI

2013-05-01

418

Power Quality Improvement in PMBLDCM Drive using PFC SEPIC Converter for Air Conditioner.  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, an improved power quality converter employing Single Ended Primary Inductor (SEPIC converter topology is used to feed a permanent magnet brushless DC motor (PMBLDCM drive. Normally, the PMBLDCM drive has a three-phase voltage source inverter (VSI and a PMBLDCM which is fed from single-phase AC mains through a diode bridge rectifier (DBR. In this proposed system a SEPIC DC-DC converter is used after the DBR and it performs power factor correction (PFC at input AC mains and voltage control at DC link, in a single-stage. The proposed PMBLDCM drive is designed, modeled and its performance is evaluated in MatlabSimulink environment for an air conditioner (Air-Con load. The speed of the compressor is controlled for efficient operation of the Air-Con which results in controlling the temperature in the conditioned area at the set point, effectively. Obtained results are presented to demonstrate an improved power quality of PFC converter based PMBLDCM drive in wide range of the speed and input AC voltage besides improved efficiency of an Air-Con system.

Athiyaman S

2013-07-01

419

A modular power electronic transformer based on a cascaded H-bridge multilevel converter  

Energy Technology Data Exchange (ETDEWEB)

In this paper a modular power electronic transformer (PET) for feeding critical loads is presented. The PE-based transformer is a multi-cellular step-down converter that can directly connect to medium voltage levels on the primary side and provide a low voltage, highly stable interface for consumer applications. The presented structure consists of three stages: a cascaded H-bridge (CHB) rectifier, an isolation stage, and an output stage. The CHB rectifier serves as an active rectifier to ensure that the input current is sinusoidal, and it converts the high AC input voltage to low DC voltages. The isolated DC/DC converters are then connected to the DC links and provide galvanic isolation between the HV and LV sides. Finally, a three-phase inverter generates the AC output with the desired amplitude and frequency. This paper introduces a new control strategy to maintain DC voltage balance among the CHB converter cells, even if the attached loads are different. The effects of voltage offsets and device mismatches on the equal load-current sharing are investigated, and an active load-current sharing method is presented to balance the load power among the parallel-output cells. The validity of the proposed controllers and the PET performance are verified by simulation and experimental results. (author)

Iman-Eini, H. [School of Electrical and Computer Engineering, University of Tehran, P.O. Box 14395-515, Tehran (Iran); G2ELab, INPG-UJF-CNRS, UMR 5269 ENSIEG, B.P. 46, F-38402 St Martin d' Heres Cedex, Grenoble (France); Farhangi, Sh. [School of Electrical and Computer Engineering, University of Tehran, P.O. Box 14395-515, Tehran (Iran); Schanen, J.-L. [G2ELab, INPG-UJF-CNRS, UMR 5269 ENSIEG, B.P. 46, F-38402 St Martin d' Heres Cedex, Grenoble (France); Khakbazan-Fard, M. [Iran Power Generation, Distribution and Transmission Management Company, Tehran (Iran)

2009-12-15

420

Progress of an electrohydraulic total artificial heart system with a separate energy converter.  

Science.gov (United States)

We have been developing an electrohydraulic total artificial heart (EHTAH) system. The system consists of diaphragm blood pumps, an abdominally placed energy converter, an internal controller, a transcutaneous energy transfer (TET) system, a transcutaneous optical information transfer system, and internal and external lithium-ion (Li-ion) batteries. The energy converter was optimized to obtain better oil transfer. Maximum cardiac output and efficiency of the EHTAH were increased from 8 L/min to 10 L/min and from 10% to 12%, respectively. The volume of the energy converter was reduced from 280 to 210 ml. The pumping unit was successfully implanted in 68-85 kg calves without anatomic problems, and the calves survived up to 10 days with good circulatory results. The maximum temperature rise of the implanted energy converter was only 1 degrees C. Stable performance of the TET system was confirmed in goats for more than 1 month. DC-DC energy transfer efficiency with 20 W of energy transmission remained within the range of 80% to 85%, and no significant temperature rise was observed in the implanted circuit. The internal Li-ion battery was also evaluated in a goat, and the maximum temperature rise during the charging period was 1.5 degrees C, while the charging and discharging times were 72 and 58 min, respectively. We conclude that our system has progressed in its development as a practical implantable system. PMID:10503628

Masuzawa, T; Tatsumi, E; Taenaka, Y; Nakamura, M; Endo, S; Takano, H; Koshiji, K; Fukui, Y; Murai, T; Tsukahara, K

1999-01-01

 
 
 
 
421

Reduction in electromagnetic interference of switching converters using self-excitation-chaos  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We derived a second-order S-switching iterative map describing the dynamics of simple feedback Buck switching regulator operating in continuous mode. Analysis of this map shows that chaos and bifurcations may occur along with the changing of values of some system parameters. By making the converter operating in chaos, the simulation results demonstrate that a reduction of spectral peak and consequent spreading of the spectrum can be shown, any desirable amount of reductio...

Li, Qingnan; Xiong, Rui; He, Ou

2011-01-01

422

The rape of Carrie Buck, Paul LombardoSite: DNA Interactive (www.dnai.org)  

Science.gov (United States)

Interviewee: Paul Lombardo DNAi Location:Chronicle>Trial of Carrie Buck>epilogue Carrie was raped After raping Carrie, Clarence Garland left Charlottesville rather than fulfill his promise to marry her.

2008-10-06

423

The Detrimental Effect of Dietary Ginger Rhizome Powder Supplementation on Reproductive Performance of Pubertal Rabbit Bucks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Thirty six crossbred rabbit bucks aged 6 months were used to study the detrimental effects of supplementing ginger rhizome powder (GRP) on reproductive performance of pubertal rabbits. The rabbit bucks were randomly divided into four experimental treatments A1, B1, C1 and D1 of nine animals and was further replicated three times with three animals per replicate in a Completely Randomized Design (CRD). The animals were fed commercial grower rabbit diet which was supplemented with GRP at the ra...

Ogbuewu, Ifeanyi Princewill; Okoli, Ifeanyi Charles; Iloeje, Michael Uwaezuoke

2013-01-01

424

High-power converters for space applications  

Science.gov (United States)

Phase 1 was a concept definition effort to extend space-type dc/dc converter technology to the megawatt level with a weight of less than 0.1 kg/kW (220 lb./MW). Two system designs were evaluated in Phase 1. Each design operates from a 5 kV stacked fuel cell source and provides a voltage step-up to 100 kV at 10 A for charging capacitors (100 pps at a duty cycle of 17 min on, 17 min off). Both designs use an MCT-based, full-bridge inverter, gaseous hydrogen cooling, and crowbar fault protection. The GE-CRD system uses an advanced high-voltage transformer/rectifier filter is series with a resonant tank circuit, driven by an inverter operating at 20 to 50 kHz. Output voltage is controlled through frequency and phase shift control. Fast transient response and stability is ensured via optimal control. Super-resonant operation employing MCTs provides the advantages of lossless snubbing, no turn-on switching loss, use of medium-speed diodes, and intrinsic current limiting under load-fault conditions. Estimated weight of the GE-CRD system is 88 kg (1.5 cu ft.). Efficiency of 94.4 percent and total system loss is 55.711 kW operating at 1 MW load power. The Maxwell system is based on a resonance transformer approach using a cascade of five LC resonant sections at 100 kHz. The 5 kV bus is converted to a square wave, stepped-up to a 100 kV sine wave by the LC sections, rectified, and filtered. Output voltage is controlled with a special series regulator circuit. Estimated weight of the Maxwell system is 83.8 kg (4.0 cu ft.). Efficiency is 87.2 percent and total system loss is 146.411 kW operating at 1 MW load power.

Park, J. N.; Cooper, Randy

1991-06-01

425

Physiological Responses of West African Dwarf Buck as Affected by Datura Stramonium Linn Seed Extract  

Directory of Open Access Journals (Sweden)

Full Text Available To evaluate the action of aqueous extract of Datura stramonium seeds on the physiological status of West African Dwarf (WAD -bucks, the effects of aqueous extract of the seed of Datura stramonium Linn was investigated for some physiological parameters in twenty (20 West African Dwarf bucks aged 12- 18 months and averaged 8.76±1.23kg for a period of 2months. The bucks were grouped into five treatments consisting four bucks and using Completely Randomized Design (CRD. The bucks were subcutaneously administered with the plant extract at a dose of 0, 0.02, 0.04, 0.06 and 0.08ml/kg bodyweight respectively. The results of the study revealed that the treated bucks had higher (p>0.05 body weight than the control but treated had lower rectal temperature than the control (p>0.05. However, the extract produced significant effect (p<0.05 on the pulse and heart rate and this may be as a result of the active principles present in the extract used for the study. Based on the findings of the present study, the aqueous extract of Datura stramonium could serve as a stimulatory agent and if properly screened using additional solvents, pharmacologically active drugs could be obtained. The significant effect produced by the aqueous extract on the animals has provided scientific justification for the ethno medicinal uses of the plant in India and South Africa.

Fatoba, T. A.

2012-12-01

426

Three-Level AC-DC-AC Z-Source Converter Using Reduced Passive Component Count  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a three-level ac-dc-ac Z-source converter with output voltage buck-boost capability. The converter is implemented by connecting a low-cost front-end diode rectifier to a neutral-point-clamped inverter through a single X-shaped LC impedance network. The inverter is controlled to switch with a three-level output voltage, where the middle neutral potential is uniquely tapped from the star-point of a wye-connected capacitive filter placed before the front-end diode rectifier f...

Loh, Poh Chiang; Gao, Feng; Tan, Pee-chin; Blaabjerg, Frede

2010-01-01

427

Ultra-Fast Tracking Power Supply with 4th order Output Filter and Fixed-Frequency Hysteretic Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A practical solution is presented for the design of a non-isolated DC/DC power converter with very low output ripple voltage and very fast output voltage step response. The converter is intended for use as an envelope tracking power supply for an RFPA (Radio Frequency Power Amplifier) in a Tetra2 base station. A simple and effective fixed-frequency hysteretic control scheme for the converter (buck with 4th order output filter) is developed and analyzed. The proposed approach is...

Høyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.

2007-01-01

428

Nine Level Inverter with Boost Converter from Renewable Energy Source  

Directory of Open Access Journals (Sweden)

Full Text Available A new single phase nine level multilevel inverter is proposed. The input to the proposed nine level multilevel inverter is obtained from solar panel . The solar energy obtained from the solar panel is not constant and it varies with times. In order to maintain the constant voltage obtained from the solar panel the boost converter is used to maintain the constant output voltage using MPPT ( Perturb and observe algorithm algorithm. Then the buck boost converter output voltage is stored in the battery bank. Finally the battery energy is connected to the 9 level inverter circuits. The harmonics in the inverter is eliminated by using the fuzzy logic controller. The gate pulse for the multilevel inverter is given by the fuzzy logic controller which in turn reduces the harmonics in the inverter. Then the inverter output is connected to the grid are some application.

Maruthu Pandiyan.R

2015-01-01

429

Design of a DC-AC Link Converter for 500W Residential Wind Generator  

Directory of Open Access Journals (Sweden)

Full Text Available  As one of alternative sources of renewable energy, wind energy has an excellence prospect in Indonesia, particularly in coastal and hilly areas which have potential wind to generate electricity for residential uses. There is urgent need to locally develop low cost inverter of wind generator system for residential use. Recent developments in power electronic converters and embedded computing allow improvement of power electronic converter devices that enable integration of microcontrollers in its design. In this project, an inverter circuit with suitable control scheme design was developed. The circuit was to be used with a selected topology of Wind Energy Conversion System (WECS to convert electricity generated by a 500W direct-drive permanent magnet type wind generator which is typical for residential use. From single phase AC output of the generator, a rectifier circuit is designed to convert AC to DC voltage. Then a DC-DC boost converter is used to step up the voltage to a nominal DC voltage suitable for domestic use. The proposed inverter then will convert the DC voltage to sinusoidal AC. The duty cycle of sinusoidal Pulse-Width Modulated (SPWM signal controlling switches in the inverter was generated by a microcontroller. The lab-scale experimental rig involves simulation of wind generator by running a geared DC motor coupled with 500W wind generator where the prototype circuit was connected at the generator output. The experimental circuit produced single phase 240V sinusoidal AC voltage with frequency of 50Hz. Measured total harmonics distortion (THD of the voltage across load was 4.0% which is within the limit of 5% as recommended by IEEE Standard 519-1992.

Riza Muhida

2012-12-01

430

Semen characteristics and sperm morphological studies of the West African Dwarf Buck treated with Aloe vera gel extract  

Directory of Open Access Journals (Sweden)

Full Text Available Background: Aloe vera (Aloe barbadensis miller is an evergreen perennial plant widely used in modern herbal practice and is often available in proprietary herbal preparations.Objective: This study was designed to investigate the semen picture and spermatozoa morphology of West African Dwarf (WAD bucks treated with Aloe vera extract.Materials and Methods: Twelve sexually matured WAD bucks, weighing between 11 and 15 kg, were used for the study. The bucks were first used as control (pre-treatment and later as two groups of six animals each. The first six bucks received 10 mls of the 3% extract while the other six received 10 mls of the 4% of the extract for a 7 day period. Semen was collected from both the 3 and 4% extract treated bucks for the control (pre-treatment, on days eight (first week post-treatment and fifteen (second week post-treatment in each case using the electroejaculation method. The spermiogram of the bucks were investigated using standard procedures. Data obtained were analyzed using two way ANOVA and significance reported at p<0.05.Results: The continuous administration of Aloe vera extract significantly (p<0.05 reduced sperm concentration, motility and percentage livability and resulted in increased sperm abnormalities in the WAD buck.Conclusion: Aloe vera adversely affected the spermiogram of bucks. The plant can reduce fertility in male animals and is therefore not recommended for medicinal purpose in male animals especially those used for breeding.

Oyeyemi Matthew Olugbenga

2011-01-01

431

The Effects of Age, Breed, Sire, Body Weight and the Ejaculate Characteristics of Rabbit Bucks  

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Full Text Available The aim of this research is to analyse the semen of different breeds of rabbits and to determine the effects of age, breed, sire, generation and body weight on the ejaculate characteristics of rabbit bucks. Twenty rabbit bucks comprising of three breeds (New-Zealand White 8, Chinchilla 6 and Californian White 6 between the ages of 6-9 months were used to investigate the effect of age, breed, sire and generation on body weight and ejaculate characteristics of the bucks. The experiment was carried out at the Animal Science departmental farm, Ahmadu Bello University, Zaria. Parameters considered include semen colour, semen volume, semen ejaculate volume, semen concentration, semen pH, sperm motility, body weight and age. The mean for semen ejaculate volume, semen concentration, pH, sperm motility, body weight and age were 0.5 mL, 325.5x106 sperm cells/mL, 7.5, 86.6, 2.0 and 7.6% months, respectively. Age, breed and sire had (p?0.05 effect on ejaculate characteristics but breed and sire had higher significant (p<0.01 effect on body weight. However, generation had no significant effect on the body weight and ejaculate characteristics except on semen pH (p<0.05. The ejaculate characteristics of the rabbit bucks were influenced by age, breed and sire. The values obtained were within the normal standards for rabbits-bucks. New Zealand White bucks proved superior in terms of ejaculate characteristics.

G.N. Akpa

2012-06-01

432

PV power system using hybrid converter for LED indictor applications  

International Nuclear Information System (INIS)

Highlights: • This paper presents a LED indictor driving circuit with a PV arrays as its power source. • The perturb-and-observe method is adopted to extract the maximum power of PV arrays. • The proposed circuit structure has a less component counts and higher conversion efficiency. • A prototype of LED indictor driving circuit has been implemented to verify its feasibility. • The proposed hybrid converter is suitable for LED inductor applications. - Abstract: This paper presents a LED indictor driving circuit with a PV arrays as its power source. The LED indictor driving circuit includes battery charger and discharger (LED driving circuit). In this research, buck converter is used as a charger, and forward converter with active clamp circuit is adopted as a discharger to drive the LED indictor. Their circuit structures use switch integration technique to simplify them and to form the proposed hybrid converter, which has a less component counts, lighter weight, smaller size, and higher conversion efficiency. Moreover, the proposed hybrid converter uses a perturb-and-observe method to extract the maximum power from PV arrays. Finally, a prototype of an LED indictor driving circuit with output voltage of 10 V and output power of 20 W has been implemented to verify its feasibility. It is suitable for the LED inductor applications

433

A 1 MEGAWATT POLYPHASE BOOST CONVERTER-MODULATOR FOR KLYSTRON PULSE APPLICATION  

International Nuclear Information System (INIS)

This paper describes electrical design criteria and first operational results a 140 kV, 1 MW average, 11 MW peak, zero-voltage-switching 20 kHz polyphase bridge, boost converter/modulator for klystron pulse application. The DC-DC converter derives the buss voltages from a standard 13.8 kV to 2300 Y substation cast-core transformer. Energy storage and filtering is provided by self-clearing metallized hazy polypropylene traction capacitors. Three ''H-Bridge'' Insulated Gate Bipolar Transistor (IGBT) switching networks are used to generate the polyphase 20 kHz transformer primary drive waveforms. The 20 kHz drive waveforms are chirped the appropriate duration to generate the desired klystron pulse width. PWM (pulse width modulation) of the individual 20 kHz pulses is utilized to provide regulated output waveforms with adaptive feedforward and feedback techniques. The boost transformer design utilizes amorphous nanocrystalline material that provides the required low core loss at design flux levels and switching frequencies. Resonant shunt-peaking is used on the transformer secondary to boost output voltage and resonate transformer leakage inductance. With the appropriate transformer leakage inductance and peaking capacitance, zero-voltage-switching of the IGBT's is attained, minimizing switching losses. A review of these design parameters and the first results of the performance characteristics will be presented

434

Fuzzy Controller Based Switched Boost Converter with Reduced Harmonics for Micro Grid Application  

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Full Text Available Z source converter is the improved version of Voltage Source Inverter (VSI which utilizes shoot through state of the switches and can be operated in both buck and boost mode of operation. The major drawbacks of Z Source Converter (ZSC is the high cost, more space and not suitable for lower power applications. In order to overcome these disadvantages, Switched Boost Converter (SBC is proposed. The proposed converter overcomes the limitations of the conventional ZSC such as lower cost, compact space and less use of passive components. This feature of SBC makes it appropriate for micro grid applications. In this study, SBC is designed for micro grid applications with Proportional-integral controller as well as fuzzy logic controller and total harmonic distortions are compared.

R. Balasubramanian

2014-01-01

435

Diseño de controladores para un convertidor flyback, operando en modo interconectado a red, para aplicaciones fotovoltaicas / Controller design for a flyback converter, in operating interconnected to grid mode, for photovoltaic applications  

Scientific Electronic Library Online (English)

Full Text Available SciELO Colombia | Language: Spanish Abstract in spanish En este artículo se presenta el modelado de un convertidor flyback integrado en un microinversor fotovoltaico de dos etapas con conexión a red, y el diseño de los controladores respectivos. La idea es obtener el modeló dinámico del convertidor DC/DC con el fin de implementar un tipo de control que p [...] ermita operar como fuente de corriente y a su vez permita regular la tensión de entrada, con base en señal resultado del algoritmo de localización del punto de máxima potencia. Dicho esquema de control es novedoso y ha sido documentado por algunos autores utilizando convertidores tipo boost. Por lo tanto, el gran aporte del presente artículo, radica en la utilización de este novedoso esquema para aprovechar la máxima energía proveniente de los paneles, empleando un convertidor que posee la característica de aislar galvánicamente la generación del resto del circuito. Para validar el funcionamiento del flyback bajo estudio, se llevaron a cabo simulaciones en PSIM™. Finalmente se presentan las conclusiones. Abstract in english This paper presents the modeling of a flyback converter integrated into a two-stage photovoltaic microinverter operating in grid connected mode and the design of the its controllers. The idea is to get the dynamic model to the DC/DC converter in order to implement a control to operate as a current s [...] ource and regulate the input voltage, based on the reference imposed by maximum power point tracker algorithm. This control scheme is novel and has been documented by several authors using boost converters. Therefore, the major contribution of this paper is the use of this novel scheme to harness the maximum energy from the panels through the employ of a converter with electrical isolation between the source and the load. To validate the operation of the flyback model under study, simulations in PSIM™ were carried out. Finally, the conclusions are presented.

César Leonardo, Trujillo Rodríguez; Nelson Leonardo, Díaz Aldana; Johann Alexander, Hernández Mora.

2012-12-01

436

Tratamento da espondilólise sintomática com reparo direto pela técnica de Buck modificada / Modified Buck's direct repair to simptomatic spondylolysis treatment / Tratamiento de la espondilolisis sintomática con preparo directo por la técnica de Buck modificada  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese OBJETIVO: justificar a reconstrução da pars interarticularis pela técnica modificada de Buck como método efetivo no tratamento de lombalgia por espondilólise ou espondilolistese tipo 1, refratárias ao tratamento conservador. MÉTODOS: avaliação retrospectiva de oito pacientes com idade entre 11 e 34 [...] anos, operados e acompanhados no período de outubro de 2004 a maio de 2008 com a técnica de Buck utilizando-se parafusos canulados de titânio. Nenhum paciente foi imobilizado no pós-operatório. Os pacientes foram selecionados após serem submetidos a estudos por imagem utilizando radiografias e ressonância magnética. Também foram avaliados no pós-operatório, segundo os critérios de Henderson e quanto à satisfação com o tratamento, assim como o índice de consolidação. RESULTADOS: sete pacientes foram classificados como excelentes, retornando ao nível de prática esportiva e laboral prévia. Dentre eles, um evoluiu com parestesia transitória, com recuperação completa. A oitava paciente apresentou uma pseudartrose bilateral, mas com bom resultado do ponto de vista clínico. Todos os pacientes ficaram satisfeitos com o resultado. CONCLUSÃO: a reconstrução ístmica com parafusos de titânio atingiu excelentes resultados ao aliar biomecânica estável, dissecção mínima da musculatura, com preservação da anatomia e mobilidade do segmento. Abstract in spanish OBJETIVO: justificar la reconstrucción de la pars interarticularis por la técnica modificada de Buck como método efectivo en el tratamiento de la lumbalgia por espondilosis o espondilolistesis tipo 1, refractarias al tratamiento conservador. MÉTODOS: evaluación retrospectiva de ocho pacientes con ed [...] ad entre 11 a 34 años, operados y acompañados en el periodo de Octubre de 2004 hasta Mayo de 2008 con la técnica de Buck usando tornillos canulados de titanio. Ningún paciente fue inmovilizado en el postoperatorio. Los pacientes fueron seleccionados después de ser sometidos a estudios por imagen utilizando radiografías y resonancias magnéticas. También fueron evaluados en el postoperatorio, según los criterios de Henderson y el grado de satisfacción con el tratamiento, así como también el índice de consolidación. RESULTADOS: siete pacientes fueron clasificados como excelentes, retornando al nivel de práctica deportiva y laboral previa. Dentro estos siete pacientes, uno evolucionó con parestesias transitorias, con recuperación completa. La octava paciente presentó una pseudoartrosis bilateral, pero con buen resultado desde el punto de vista clínico. Todos los pacientes quedaron satisfechos con el resultado. CONCLUSIÓN: la reconstrucción ístmica con tornillos de titanio tuvo excelentes resultados al juntar biomecánica estable, disección mínima de la musculatura, con preservación de la anatomía y modalidad del segmento. Abstract in english OBJECTIVE: to justify the modified Buck's technique of pars reconstruction as an effective method to spondylolysis and low grade spondylolisthesis treatment. METHODS: eight patients with ages 11 to 34 years were retrospectively evaluated from October 2004 to may 2008. They were operated with Buck´s [...] technique using titanium canulated screws. Immobilization wasn't used in any patient in post-operative period. All patients were studied with magnetic resonance imaging. All patients were assessed in post-operative period with Henderson's criteria of functional capacity. RESULTS: seven patients were assessed as excellent. They didn´t complain pain and were able to return to former occupation and sportive activities. One patient presented temporary paresthesia and leg weakness, and one patient bilateral pseudoarthrosis that cursed with good grade functional capacity. All patients were satisfied with treatment. CONCLUSION: the isthmic reconstruction using titanium scre