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1

Study of Sliding Mode Control of DC-DC Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, a robust sliding mode controller for the control of dc-dc buck converter is designed and analyzed. Dynamic equations describing the buck converter are derived and sliding mode controller is designed. A two-loop control is employed for a buck converter. The robustness of the sliding mo...

Hanifi Guldemir

2

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 asvoltage mode control or current mode control, statecontrol technique is more precise because it uses allmain state values to increase the dynamicperformances of the power converter. The paperincludes simulation results that indicate the usefulnessfor possible future hardware implementation. Theauthors used in requested computations for themodeling, control and simulation MATLABprogramming environment and SIMULINK. Thedesign methodology is useful also for convertors with amore complex topology than the DC-DC buckconverter, even if they operate in the case ofdiscontinuous conduction mode.

TRIP Nistor Daniel; POPESCU Viorel; DUDRIK Jaroslav

2010-01-01

3

Comparison and Simulation of Full Bridge and LCL-T Buck DC-DC Converter Systems  

Directory of Open Access Journals (Sweden)

Full Text Available The DC-DC Converter topologies have received increasing attention in recent years for Low power and high performance applications. The advantages DC-DC buck converters includes increased efficiency, reduced size, reduced EMI, faster transient response and improved reliability. The front end LCL-T in a buck converter is connected in sequence manner to improve the electrical performances and to reduce the switching losses. It futures several merits such as multi output capability and also will associate with one or two capacitors so has to improve resonant operations. This paper compares conventional buck converter and LCL-T type converter designed for low voltage and low power applications and simulation results are compared for both converters

A Mallikarjuna Prasad; B Gururaj; S Sivanagaraju

2012-01-01

4

Study of Sliding Mode Control of DC-DC Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, a robust sliding mode controller for the control of dc-dc buck converter is designed and analyzed. Dynamic equations describing the buck converter are derived and sliding mode controller is designed. A two-loop control is employed for a buck converter. The robustness of the sliding mode controlled buck converter system is tested for step load changes and input voltage variations. The theoretical predictions are validated by means of simulations. Matlab/Simulink is used for the simulations. The simulation results are presented. The buck converter is tested with operating point changes and parameter uncertainties. Fast dynamic response of the output voltage and robustness to load and input voltage variations are obtained.

Hanifi Guldemir

2011-01-01

5

Voltage Tracking of a DC-DC Buck-Boost Converter Using Neural Network Control  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes a neural network control scheme of a DC-DC Buck-Boost converter to produce variable DC voltage source that will be applied on DC motor drives. In this technique, a back propagation learning algorithm is derived. The controller is designed to track the output voltage of the DC-DC converter and to improve performance of the Buck-Boost converter during transient operations. Furthermore, to investigate the effectiveness of the proposed controller, some operations such as starting-up and reference voltage variations are verified. The numerical simulation results show that the proposed controller has a better performance compare to the conventional PI-Controller method.

W.M.Utomo,; Z.A. Haron, A. A. Bakar, M. Z. Ahmad, Y.M.Y Buswig and S.F. Mansour

2011-01-01

6

A Study on the Simultaneous Control of Buck and DC-DC Converter by Fuzzy Controller  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a multi output converter systems that controls, simultaneously, the separate buck converter and boost converter with the different specification by one digital controller using fuzzy algorithm. As two separate converters are regulated by only one DSP, it is possible to achieve the simple digital control circuit for regulating multi output DC-DC converter. Inference procedure of fuzzy controller is included. The control characteristics of each PWN DC-CD converter validated by experimental result. (author). 8 refs., 8 figs., 2 tabs.

Park, Hyo Sik; Kim, Hee Jun [Hanyang University, Seoul (Korea)

2001-02-01

7

Controller Design of buck dc/dc converter using neural networks  

International Nuclear Information System (INIS)

Nowadays, dc-dc topologies are widely utilized in many industrial applications due to their high efficiency, fast switching actions, low volume and weight and low cost. DC-DC converter is a big family of converters and consist more than thousand of topologies. Buck converter is one of the types of such family and only operates in the step-down mode. Such converter is highly under damped system and contains nonlinearities which lead to oscillations during operation. During last few decades various new control techniques have been investigated and analyzed in order to overcome the developed oscillation in output of this converter. Recently, NNCs (Neural Network Controllers) are gaining popularity in modeling, identification and control of power electronic converters. These controllers are advanced controllers and have fast dynamic behaviour and robustness. The NNCs are nonlinear controllers which enhance the system performance, increase system speed and reduce the system complexity. In this research work, NNCs are designed for Buck topology to minimize uncertainties. The operation of Buck topology with designed NNCs is analyzed during line and load variations and results are compared with results of PI (Proportional and Integral) controller.

2010-01-01

8

Analysis of DC-DC Buck converter with chaotic dynamics using Wigner Distribution  

Directory of Open Access Journals (Sweden)

Full Text Available DC/DC converters exhibit subharmonicsand chaos when the switching action is governed byfeedback control. Since the use of converters isincreasing in Industries for various applications,deeper analysis of the appearance and the nature ofbifurcation is essential to stabilize its output onto adesired periodic solution. Time frequencyrepresentation is helpful in studying the fine structuresof frequency patterns such as sub harmonics and ultraharmonics of chaotic dynamics. This paper analyzesthe changing frequency patterns during bifurcationprocesses of the nonlinear DC-DC Buck converterusing Wigner-Ville distribution method as patternrecognition method. This information leads to a betterunderstanding of the system that may allow us todesign a stable, chaotic free converter and could beused as a diagnostic for detecting different nonlineardynamic responses.

LOGAMANI Premalatha

2010-01-01

9

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 in both buck and boost modes of converter operation. Since this converter can operate over a wide input voltage range, it can be employed in power factor correction. The experimental results obtained from a 150W prototype circuit operating at 100KHz are presented to confirm the integrity of the proposed circuit.

Majid Delshad

2010-01-01

10

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

2005-01-01

11

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

Directory of Open Access Journals (Sweden)

Full Text Available 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; Goce L. Arsov

2010-01-01

12

A Study on the Simultaneous Control of Buck and Boost DC-DC Converter by Digital Controller  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a one digital controller two topology PWM DC-DC converter that controls, simultaneously, the separate Buck converter and boost converter with the different specification by using an inexpensive and efficient 8 bit micro-controller. One timer interrupt is used for the detection of output feedback voltage, and other two timer interrupts are used for the generation of PWM waveform for Buck and Boost converter. The control characteristics of one digital controller two topology PWM DC-DC converter is validated by experimental results. (author). 7 refs., 11 figs.

Park, Hyo Sik; Kim, Hee Jun [Hanyang University, Seoul (Korea)

2001-03-01

13

Design of Controllers for Single-Input Dual-Output Synchronous DC-DC Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Design and control techniques for a Single Input Dual Output (SIDO) Synchronous DC-DC Buck Converter are presented. The advantage of this converter eliminates one MOSFET switch and its drive circuitry when compared to the conventional converter and in this system both output voltages are generated by the same integrated power converter. A Genetic Algorithm assisted PI controller is designed to maintain the output voltages to a constant value against load and line variations and compared with existing PI controller. The parameters of the controller are designed using various techniques like SISOTOOL (GUI), Internal Model Control and Binary Genetic Algorithm. The Discrete PI controller is also developed for the above converter. All the controllers are simulated using MATLAB and their performances are compared in terms of Peak overshoot, Rise time and Settling time. The system is also developed using real components and the results are obtained in open loop mode.

S.Augustilindiya; S.Palani; K.Vijayarekha; V.Sreenath

2013-01-01

14

A low noise high efficiency buck DC-DC converter with sigma-delta modulation  

International Nuclear Information System (INIS)

Some research efforts to improve the efficiency and noise performance of buck DC-DC converters are explored. A carefully designed power MOSFET driver, including a dead time controller, discontinuous current mode (DCM) controller and gate width controller, is proposed to improve efficiency. Instead of PWM modulation, sigma-delta modulation is introduced into the feedback loop of the converter to move out the clock-referred harmonic spike. The proposed converter has been designed and fabricated by a 0.35 ?m CMOS process. Measured results show that the peak efficiency of the converter can reach 93% and sigma-delta modulation suppresses the harmonic spike by 30 dB over PWM modulation. (semiconductor integrated circuits)

2011-01-01

15

New control law of boost and buck-boost DC-DC converters. Boost gata oyobi buck-boost gata DC DC henkanki ni taisuru shinseigyo hoshiki  

Energy Technology Data Exchange (ETDEWEB)

Boost and buck-boost DC-DC converters formulated as bilinear systems are studied in the state-space representation to derive a new control law. The obtained control law seeks a nonlinear feedback rule from the stability theory by considering output regulation based on the large signal model not relying on linear approxmation etc. for the bilinear system capable of being expressed by using the state-space averaging method. It was found out that the control law obtained as the result of this is somewhat complicated compared with the old control system but has good stability and response characteristics. Its practical application is problematic for the present in the hardware structure, unconsidered matter in computer simulation, etc. and nevertheless hopeful in the future. 10 refs., 8 figs.

Iawasaki, N. (Joetsu Universtiy of Education, Niigata (Japan)); Nomura, H. (Kochi National College of Technology, Kochi (Japan))

1991-09-20

16

HIGH PERFORMANCE ALGORITHMS FOR THE CONTROL OF BUCK DC-DC CONVERTERS  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, two control methods are presented for controlling the DC-DC converters. These proposed control algorithms are tailored to buck DC-DC converter, so as to optimize the performance of the converter. First, a model predictive control (MPC) method which uses a short prediction horizon is proposed. Since a short prediction horizon is used, the optimization solution can be derived analytically so that the algorithm becomes simple enough and can be implemented on-line. Further, the reference tracking error of inductance current is chosen as the penalized output. Second, a three-level hysteresis control method is proposed. This is naturally the extension of the conventional hysteresis control. The basic principle is to set the duty ratio in the central layer band as the steady-state duty ratio. Lastly, the load identification based on an adaptation of fuzzy control is proposed. Computer simulations have been carried out to investigate the effectiveness of the proposedalgorithms. Comparison with the well-known PID-PWM method is also presented. The advantage of this approach lies in its good trade-off between simple implementation, rise-time and overshoot in the output voltage response.

ABU ZAHARIN AHMAD,; KANG-ZHI LIU; HARUKA KINOSHITA

2010-01-01

17

Design of high efficiency dual-mode buck DC-DC converter  

International Nuclear Information System (INIS)

A buck DC-DC switching regulator with high efficiency is implemented by automatically altering the modulation mode according to load current, and it can operate with an input range of 4.5 to 30 V. At light load current, the converter operates in skip mode. The converter enters PWM mode operation with increasing load current. It reduces the switching loss at light load and standby state, which results in prolonging battery lifetime and stand-by time. Meanwhile, externally adjustable soft-start minimizes the inrush supply current and avoids the overshoot of output voltage at initial startup. The regulator is fabricated by a 0.6 ?m CDMOS process. The test results show that, under the condition of 3.3 V output, the efficiency is up to 64% at 5 mA and the maximum efficiency is 95.5%.

2010-01-01

18

Quantized Feedback Control Software Synthesis from System Level Formal Specifications for Buck DC/DC Converters  

CERN Multimedia

Many Embedded Systems are indeed Software Based Control Systems (SBCSs), that is control systems whose controller consists of control software running on a microcontroller device. This motivates investigation on Formal Model Based Design approaches for automatic synthesis of SBCS control software. In previous works we presented an algorithm, along with a tool QKS implementing it, that from a formal model (as a Discrete Time Linear Hybrid System, DTLHS) of the controlled system (plant), implementation specifications (that is, number of bits in the Analog-to-Digital, AD, conversion) and System Level Formal Specifications (that is, safety and liveness requirements for the closed loop system) returns correct-by-construction control software that has a Worst Case Execution Time (WCET) linear in the number of AD bits and meets the given specifications. In this technical report we present full experimental results on using it to synthesize control software for two versions of buck DC-DC converters (single-input and ...

Mari, Federico; Salvo, Ivano; Tronci, Enrico

2011-01-01

19

Integrated Circuit of CMOS DC-DC Buck Converter with Differential Active Inductor  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, we propose a new design of DC-DC buck converter (BC), which the spiral inductor is replaced by a differential gyrator with capacitor load (gyrator-C) implemented in 0.18um CMOS process. The gyrator-C transforms the capacitor load (which is the parasitic capacitor of MOSFETS) to differential active inductor DAI. The low-Q value of DAI at switching frequency of converter (few hundred kHz) is boosted by adding a negative impedance converter (NIC). The transistor parameters of DAI and NIC can be properly chosen to achieve the desirable value of equivalent inductance L (few tens H), and the maximum-Q value at the switching frequency, and thus the efficiency of converter is improved. Experimental results show that the converter supplied with an input voltage of 1V, provides an output voltage of 0.74V and output ripple voltage of 10mV at 155 kHz and Q-value is maximum (#8776;4226) at this frequency.

Kaoutar Elbakkar; Khadija Slaoui

2011-01-01

20

Adaptive terminal sliding-mode control strategy for DC-DC buck converters.  

UK PubMed Central (United Kingdom)

This paper presents an adaptive terminal sliding mode control (ATSMC) strategy for DC-DC buck converters. The idea behind this strategy is to use the terminal sliding mode control (TSMC) approach to assure finite time convergence of the output voltage error to the equilibrium point and integrate an adaptive law to the TSMC strategy so as to achieve a dynamic sliding line during the load variations. In addition, the influence of the controller parameters on the performance of closed-loop system is investigated. It is observed that the start up response of the output voltage becomes faster with increasing value of the fractional power used in the sliding function. On the other hand, the transient response of the output voltage, caused by the step change in the load, becomes faster with decreasing the value of the fractional power. Therefore, the value of fractional power is to be chosen to make a compromise between start up and transient responses of the converter. Performance of the proposed ATSMC strategy has been tested through computer simulations and experiments. The simulation results of the proposed ATSMC strategy are compared with the conventional SMC and TSMC strategies. It is shown that the ATSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes.

Komurcugil H

2012-11-01

 
 
 
 
21

Adaptive terminal sliding-mode control strategy for DC-DC buck converters.  

Science.gov (United States)

This paper presents an adaptive terminal sliding mode control (ATSMC) strategy for DC-DC buck converters. The idea behind this strategy is to use the terminal sliding mode control (TSMC) approach to assure finite time convergence of the output voltage error to the equilibrium point and integrate an adaptive law to the TSMC strategy so as to achieve a dynamic sliding line during the load variations. In addition, the influence of the controller parameters on the performance of closed-loop system is investigated. It is observed that the start up response of the output voltage becomes faster with increasing value of the fractional power used in the sliding function. On the other hand, the transient response of the output voltage, caused by the step change in the load, becomes faster with decreasing the value of the fractional power. Therefore, the value of fractional power is to be chosen to make a compromise between start up and transient responses of the converter. Performance of the proposed ATSMC strategy has been tested through computer simulations and experiments. The simulation results of the proposed ATSMC strategy are compared with the conventional SMC and TSMC strategies. It is shown that the ATSMC exhibits a considerable improvement in terms of a faster output voltage response during load changes. PMID:22877744

Komurcugil, Hasan

2012-08-09

22

A fast novel soft-start circuit for peak current-mode DC—DC buck converters  

International Nuclear Information System (INIS)

A fully integrated soft-start circuit for DC—DC buck converters is presented. The proposed high speed soft-start circuit is made of two sections: an overshoot suppression circuit and an inrush current suppression circuit. The overshoot suppression circuit is presented to control the input of the error amplifier to make output voltage limit increase in steps without using an external capacitor. A variable clock signal is adopted in the inrush current suppression circuit to increase the duty cycle of the system and suppress the inrush current. The DC—DC converter with the proposed soft-start circuit has been fabricated with a standard 0.13 ?m CMOS process. Experimental results show that the proposed high speed soft-start circuit has achieved less than 50 ?s start-up time. The inductor current and the output voltage increase smoothly over the whole load range. (semiconductor integrated circuits)

2013-01-01

23

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 model for a PEM fuel cell that can be used to design fuel cell simulator. The model is consisted of a DC-DC buck converter driven by PIC 16F877 microcontroller. The model can be used in design and analysis of fuel cell power systems by simulation or by using practically realized simulator.

Goce L. Arsov; Georgi Georgievski

2009-01-01

24

A Comparative study of Analog and digital Controller On DC/DC Buck-Boost Converter Four Switch for Mobile Device Applications  

Directory of Open Access Journals (Sweden)

Full Text Available this paper presents comparative performance between Analog and digital controller on DC/DC buck-boost converter four switch. The design of power electronic converter circuit with the use of closed loop scheme needs modeling and then simulating the converter using the modeled equations. This can easily be done with the help of state equations and MATLAB/SIMULINK as a tool for simulation of those state equations. DC/DC Buckboost converter in this study is operated in buck (step-down) and boost (step-up) modes.

Benlafkih Abdessamad; Krit Salah-Ddine; Chafik Elidrissi Mohamed

2013-01-01

25

DCM, FSM, dead time and width controllers for a high frequency high efficiency buck DC-DC converter over a wide load range  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a width controller, a dead time controller, a discontinuous current mode (DCM) controller and a frequency skipping modulation (FSM) controller for a high frequency high efficiency buck DC-DC converter. To improve the efficiency over a wide load range, especially at high switching frequency, the dead time controller and width controller are applied to enhance the high load efficiency, while the DCM controller and FSM controller are proposed to increase the light load efficiency. The proposed DC-DC converter controllers have been designed and fabricated in the Chartered 0.35 {mu}m CMOS process, and the measured results show that the efficiency of the buck DC-DC converter is above 80% over a wide load current range from 8 to 570 mA, and the peak efficiency is 86% at 10 MHz switching frequency. (semiconductor integrated circuits)

Pi Changming; Yan Wei; Zhang Ke; Li Wenhong, E-mail: wenhongli@fudan.edu.c [State Key Laboratory of ASIC and Systems, Fudan University, Shanghai 201203 (China)

2010-08-15

26

DCM, FSM, dead time and width controllers for a high frequency high efficiency buck DC-DC converter over a wide load range  

International Nuclear Information System (INIS)

This paper presents a width controller, a dead time controller, a discontinuous current mode (DCM) controller and a frequency skipping modulation (FSM) controller for a high frequency high efficiency buck DC-DC converter. To improve the efficiency over a wide load range, especially at high switching frequency, the dead time controller and width controller are applied to enhance the high load efficiency, while the DCM controller and FSM controller are proposed to increase the light load efficiency. The proposed DC-DC converter controllers have been designed and fabricated in the Chartered 0.35 ?m CMOS process, and the measured results show that the efficiency of the buck DC-DC converter is above 80% over a wide load current range from 8 to 570 mA, and the peak efficiency is 86% at 10 MHz switching frequency. (semiconductor integrated circuits)

2010-01-01

27

SEMICONDUCTOR INTEGRATED CIRCUITS: DCM, FSM, dead time and width controllers for a high frequency high efficiency buck DC-DC converter over a wide load range  

Science.gov (United States)

This paper presents a width controller, a dead time controller, a discontinuous current mode (DCM) controller and a frequency skipping modulation (FSM) controller for a high frequency high efficiency buck DC-DC converter. To improve the efficiency over a wide load range, especially at high switching frequency, the dead time controller and width controller are applied to enhance the high load efficiency, while the DCM controller and FSM controller are proposed to increase the light load efficiency. The proposed DC-DC converter controllers have been designed and fabricated in the Chartered 0.35 ?m CMOS process, and the measured results show that the efficiency of the buck DC-DC converter is above 80% over a wide load current range from 8 to 570 mA, and the peak efficiency is 86% at 10 MHz switching frequency.

Changming, Pi; Wei, Yan; Ke, Zhang; Wenhong, Li

2010-08-01

28

Dc-dc converter  

Energy Technology Data Exchange (ETDEWEB)

In a dc-dc converter of the type in which an inductance stores energy when a main switching transistor is turned on and releases the stored energy when the main switching transistor is turned off, a semiconductor active element is used as a flywheel element which is turned off when the main switching element is turned on, but is turned on to provide the path for the current established by the release of the stored energy, an auxiliary diode is connected in parallel with the semiconductor active element and in the same forward direction, and the signal which is substantially in synchronism with the switching operation of the main switching transistor is applied to the control terminal of the semiconductor active element so as to cause it to turn on and off.

Arai, N.; Ikenoue, T.; Liu, S.; Umemoto, S.

1982-11-02

29

Diseño estático de un convertidor DC/DC reductor-elevador bidireccional/ Bidirectional buck-boost dc/dc converter static design  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Se presenta el diseño estático de un convertidor reductor-elevador bidireccional con tres conmutadores y conexión en cascada. La principal aplicación del convertidor es la administración de baterías en sistemas de alimentación ininterrumpida, controlando el flujo de energía y regulando la tensión de alimentación DC durante los diferentes modos de operación de la batería como fuente y sumidero. Abstract in english 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, controlling energy flow and regulating the DC supply voltage for the different battery operation modes as source and sink.

González Valencia, Marcela; Alzate Gómez, Alfonso

2010-06-01

30

Non-linear design of dc-dc buck converter to assess the performance under steady state and dynamic operation  

International Nuclear Information System (INIS)

Buck converters are widely used in switch mode power supplies due to their high efficiency, fast switching actions, low volume and weight, and low cost. These converters are variable structure systems and contain nonlinearities which lead to oscillations during operation. Various Control techniques have been investigated and analyzed in order to minimize oscillations during the operation of the converter, in particular, under non-linear situations. In this paper, an attempt is being made to control the oscillation of the buck converter by using sliding mode controller. The SMC (Sliding Mode Controller) is a nonlinear controller which can handle nonlinearities, provides good dynamic response and simple implementation. The proposed control scheme is implemented and simulated in MATLAB/Simulink. The results of SMC are compared with cascade controller and are presented in this paper. (author)

2009-01-01

31

Design of PWM based sliding mode voltage controller for DC-DC converters operating in continuous conduction mode  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a simple approach to the design of fixed-frequency pulse-width-modulation based sliding mode voltage controller for DC-DC converters operating in continuous conduction mode. The design methodology is illustrated on the three basic DC-DC converters: buck, boost, and buck-boost con...

Tan, SC; Lai, YM; Tse, CK

32

Soft switching active snubbers for DC/DC converters  

Energy Technology Data Exchange (ETDEWEB)

A soft-switching active snubber is proposed to reduce the turn-off losses of the insulated gate bipolar transistor (IGBT) in a buck converter. The soft-switching snubber provides zero-voltage switching for the IGBT, thereby reducing its high turn-off losses due to the current tailing. The proposed snubber uses an auxiliary switch to discharge the snubber capacitor. This auxiliary switch also operates at zero-voltage and zero-current switching. The size of the auxiliary switch compared to the main switch makes this snubber a good alternative to the conventional snubber or even to passive low-loss snubbers. The use of the soft-switching active snubber permits the IGBT to operate at high frequencies with an improved RBSOA. In the experimental results reported for a 1 kW, 40 kHz prototype, combined switching/snubbing losses are reduced by 36% through the use of the active snubber compared to a conventional RCD snubber. The use of an active snubber capacitor during turn-off. The generic snubber cell for the buck converter is generalized to support the common nonisolated dc/dc converters (buck, boost, buck-boost, Cuk, sepic, zeta) as well as isolated dc/dc converters (forward, flyback, Cuk, and sepic).

Elasser, A.; Torrey, D.A. [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Electric Power Engineering

1996-09-01

33

General-purpose fuzzy controller for dc-dc converters  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a general-purpose fuzzy controller for dc-dc converters is investigated. Based on a qualitative description of the system to be controlled, fuzzy controllers are capable of good performances, even for those systems where linear control techniques fail, e.g., when a mathematical description is not available or is in the presence of wide parameter variations. The presented approach is general and can be applied to any dc-dc converter topologies. Controller implementation is relatively simple and can guarantee a small-signal response as fast and stable as other standard regulators and an improved large-signal response. Simulation results of Buck-Boost and Sepic converters show control potentialities.

Mattavelli, P.; Rossetto, L.; Spiazzi, G.; Tenti, P. [Univ. of Padova (Italy)

1997-01-01

34

DC/DC Converter Stability Testing Study.  

Science.gov (United States)

This report presents study results on hybrid DC/DC converter stability testing methods. An input impedance measurement method and a gain/phase margin measurement method were evaluated to be effective to determine front-end oscillation and feedback loop os...

B. L. Wang

2008-01-01

35

Energy saving dc-dc converter circuit  

International Nuclear Information System (INIS)

An energy saving dc-dc converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means and a voltage doubling means. These energy efficient means are applied in combination with elements commonly found in dc-dc converter circuits, namely an ac voltage generator, a transformer for stepping up the generated ac voltage, and means for storing the converted dc voltage. The energy conserving means is connected to the dc voltage storage means. It comprises a resettable inhibit circuit which cuts off the provision of dc voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit of the energy conserving means and the ac voltage generator. It provides a phase inverted waveform of the generated ac voltage on one of two leads to the ac voltage step-up transformer

1982-01-01

36

Energy saving dc-dc converter circuit  

Energy Technology Data Exchange (ETDEWEB)

An energy saving dc-dc converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means and a voltage doubling means. These energy efficient means are applied in combination with elements commonly found in dc-dc converter circuits, namely an ac voltage generator, a transformer for stepping up the generated ac voltage, and means for storing the converted dc voltage. The energy conserving means is connected to the dc voltage storage means. It comprises a resettable inhibit circuit which cuts off the provision of dc voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit of the energy conserving means and the ac voltage generator. It provides a phase inverted waveform of the generated ac voltage on one of two leads to the ac voltage step-up transformer.

Brantley, W.C.; Edington, J.E.

1982-06-22

37

An Efficient DC- DC Converter with Bidirectional Power Flow  

Directory of Open Access Journals (Sweden)

Full Text Available This paper introduces a Bi-directional DC-DC converter with adaptive fuzzy logic controller. Bidirectional power flow is obtained by same power components and provides a simple, efficient, and galvanically isolated converter. In the presence of DC mains the converter operates as buck converter and charges the battery. When the DC mains fails, the converter operates as boost converter and the down stream converter is fed by the battery. The power switches are controlled by Pulse Width Modulation technique and the pulses are generated by the application of fuzzy logic with an adoption algorithm. The proposed converter is simulated using MATLAB and laboratory prototype was developed to validate the simulation results.

N.RAJARAJESWARI; K.THANUSHKODI

2008-01-01

38

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

39

An Integrated High Efficiency DC-DC Converter in 65 nm CMOS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This thesis work describes the implementation perspective of an integrated high efficiency DC-DC converter implemented in 65 nm CMOS. The implemented system employs the Buck converter topology to down-convert the input battery voltages. This converter offers its use as a power management unit in por...

Manh, Vir Varinder

40

Bifurcations in Current-Programmed DC/DC Buck Switching Regulators - Conjecturing a Universal Bifurcation Path  

UK PubMed Central (United Kingdom)

This paper studies the bifurcation paths exhibited by a DC=DC buck switching regulator under current-programmed control.Previous studies with the boost converter and the # Cuk converter have shown that two distinct types of bifurcation paths,namely one that goes through a region of quasi-periodic orbits and via period-doubling, are possible. We conjecture thatthese two di#erent types of bifurcation paths are part of another bifurcation in which the quasi-periodic sequence transmutesinto the period-doubling sequence, and that such a bifurcation is characteristic of current-programmed DC=DC converters.In this paper we demonstrate that such a universal phenomenon is manifested in the current-programmed buck switchingregulator. We shall derive the describing iterative map in closed form and use it to develop the main results via a seriesof computer experiments. The characteristic multipliers are calculated and the #rst on-set of #ip-bifurcation is predicted.Computer simulations from the `exact' model verify the results. The exhibition of quasi-periodic orbits is con#rmed bycomputation of the Lyapunov exponent. Finally, a series of return maps are generated to provide an alternative viewpointto the reported bifurcations in terms of a transmutation from a tent-like map to a logistic-like map. ? 1998 John Wiley& Sons, Ltd.1. INTRODUCTIONRecently, chaos from DC=DC converter circuits under current-programmed control has been reported.

Bifurcations In; Current-programmed Dc=dc Buck; William C. Y. Chan; C. K. Tse

 
 
 
 
41

Sliding Mode Control of Dc-Dc Boost Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Control of Dc-Dc boost converter is a complex task due to the nonlinearity inherent in the converter and introduced by the external changes. A robust sliding mode controller for the control of Dc-Dc boost converter were described in this study. Dynamic equations describing the boost converter are de...

Hanifi Guldemir

42

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; A. A. MAHFOUZ; D. M. KHORSHIED

2012-01-01

43

HYBRID MODELING OF OPEN LOOP DC-DC CONVERTERS  

Scientific Electronic Library Online (English)

Full Text Available 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 behaviors 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 (more) 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

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

2003-12-01

44

Extra-High-Voltage DC-DC Boost Converters Topology with Simple Control Strategy  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the topology of operating DC-DC buck converter in boost mode for extra-high-voltage applications. Traditional DC-DC boost converters are used in high-voltage applications, but they are not economical due to the limited output voltage, efficiency and they require two sensors with complex control algorithm. Moreover, due to the effect of parasitic elements the output voltage and power transfer efficiency of DC-DC converters are limited. These limitations are overcome by using the voltage lift technique, opens a good way to improve the performance characteristics of DC-DC converter. The technique is applied to DC-DC converter and a simplified control algorithm in this paper. The performance of the controller is studied for both line and load disturbances. These converters perform positive DC-DC voltage increasing conversion with high power density, high efficiency, low cost in simple structure, small ripples, and wide range of control. Simulation results along theoretical analysis are provided to verify its performance.

P. Sanjeevikumar; K. Rajambal

2009-01-01

45

Custom DC-DC converters for distributing power in SLHC trackers  

CERN Multimedia

A power distribution scheme based on the use of on-board DC-DC converters is proposed to efficiently distribute power to the on-detector electronics of SLHC trackers. A comparative analysis of different promising converter topologies is presented, leading to the choice of a magneticbased buck converter as a first conversion stage followed by an on-chip switched capacitors converter. An overall efficiency above 80% is estimated for the practical implementation proposed.

Allongue, B; Blanchot, G; Faccio, F; Fuentes, C; Mattavelli, P; Michelis, S; Orlandis, S; Spiazzi, G

2008-01-01

46

Analysis of the Coupling Behavior of PEM Fuel Cells and DC-DC Converters  

Directory of Open Access Journals (Sweden)

Full Text Available The connection between PEM fuel cells and common DC-DC converters is examined. The analysis is model-based and done for boost, buck and buck-boost converters. In a first step, the effect of the converter ripples upon the PEM fuel cell is shown. They introduce oscillations in the fuel cell. Their appearance is explained, discussed and possibilities for their suppression are given. After that, the overall behaviors of the coupled fuel cell-converter systems are analyzed. It is shown, that neither stationary multiplicities nor oscillations can be introduced by the couplings and therefore separate control approaches for both the PEMFC and the DC-DC converters are applicable.

Markus Grötsch; Michael Mangold; Achim Kienle

2009-01-01

47

Unifying Derivation of Switching DC-DC Converter Topologies.  

Science.gov (United States)

A canonical switching cell is proposed from which the three basic dc-dc converter topologies can be derived. In addition, it is possible to perform topological transformations which yield apparently new topologies. Upon examination, however, these topolog...

E. E. Landsman

1979-01-01

48

Simulation analysis of cascade controller for DC-DC bank converter  

International Nuclear Information System (INIS)

Power electronic converters are periodic variable structure systems due to their switched operation. During the last few decades several new dc-dc converter topologies have emerged. Buck converter being simple in topology, has recently drawn attraction of many researchers. Basically, a buck converter is highly underdamped system. In order to overcome the developed oscillations in output of this converter, various control techniques have been proposed. However, these techniques are fraught with many drawbacks. This paper focus on a cascade controller based buck topology. Steady state analysis is given in this paper which shows output voltage and inductor current in detail. Dynamic analysis for line and load variation is also presented. The buck topology is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)

2009-01-01

49

High Power Density DC/DC Converter: Selection of Converter Topology.  

Science.gov (United States)

The work involved in the identification and selection of a suitable converter topology is described. Three new dc/dc converter topologies are proposed: Phase-Shifted Single Active Bridge DC/DC Converter; Single Phase Dual Active Bridges DC/DC Converter; a...

D. M. Divan

1990-01-01

50

Dynamic Evolution Control for Fuel Cell DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Fuel cells are new alternative energy resource that has a great promise for distributed generation and electric vehicle application. However, fuel cells have a slow response due to their slow internal electromechanical and thermodynamic response. To optimize the fuel cell system performance, a fuel cell DC-DC converter with an appropriate controller which can regulate the power flow and automatically adjust the converter output voltage is needed. This paper proposes a new control technique for fuel cell DC-DC power converter. Design of the proposed control method for fuel cell DC-DC power converter is provided. A new approach for converter controllers synthesis based on dynamic evolution control theory is presented. In this paper, synthesis example of boost DC-DC converter is discussed. Performance of the proposed dynamic evolution control under step load variation condition is simulated under Matlab-Simulink environment. Simulation results show that the proposed techniques are capable for controlling fuel cell DC-DC converter.

Ahmad Saudi Samosir; Tole Sutikno; Abdul Halim Mohd Yatim

2011-01-01

51

Pseudo-resonant full bridge dc/dc converter  

Energy Technology Data Exchange (ETDEWEB)

In this paper a new dc/dc converter topology is proposed which combines the ease of control and wide range of conventional dc/dc converters, with low switching losses, low dv/dt and low EMI that is typical of zero voltage switched resonant converters. Consequently, the ratings of these components are substantially lower than for similarly rated resonant topologies. Operation at very high frequencies is possible and is shown with the fabrication of a 200 W 1 MHz d/dc converter.

Patterson, O.D.; Divan, D.M. (Wisconsin Univ., Madison, WI (United States). Dept. of Electrical and Computer Engineering)

1991-10-01

52

DC-DC converter for hybrid vehicles; Shasaiyo DC-DC converter  

Energy Technology Data Exchange (ETDEWEB)

In response to the decisions adopted at the Third Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (Kyoto conference for the prevention of global warming) of 1997, hybrid vehicles, electric vehicles, and the like are being announced of their completion or placed on the market one after another as low pollution vehicles with CO2 emission to cause global warming reduced. Fuji Electric Co., Ltd., is engaged in the development of a DC-DC converter for hybrid vehicles in cooperation with Nissan Motor Co., Ltd. The product is characterized in (1) that it is small in size and light in weight because a step-down converter and an emergency step-up converter are integrated; (2) that it enjoys a high efficiency rate of 89%; (3) that its service life is long thanks to its design free of aluminum electrolytic capacitors; and (4) that it is provided with various reliability improving features, such as protective systems and warning signal outputting means. A series will be organized in which the above-introduced product is a member, and efforts will continue to further enhance efficiency, noise reduction, and miniaturization. (translated by NEDO)

NONE

2000-01-10

53

METHOD FOR GENERATING DC-DC CONVERTERS WITH REQUIRED CHARACTERISTICS  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes an algorithmic method for generating DC–DC converters with predetermined characteristics. This method uses the Main Topological Matrix MTM. The definition and attributes of the MTM are stated. The common properties for single-switch DC-DC converters are described. The proposed method has unique advantages over other methods. This method is fully algorithmic. In addition, this method basses on the design by parts, that facilitates the design of power electronic circuits. Moreover, by some examples we will show how this method used for generating all sub-class (sub-family) of DC-DC converters with predetermined characteristics (e.g. galvanic isolation).

Murad Ahmed Ali Taher

2012-01-01

54

A New Soft-Switched Resonant DC-DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new soft-switched resonant dc-dc converter using a passive snubber circuit. The proposed converter uses a new zero voltage and zero current switching (ZVZCS) strategies to get ZVZCS function. Besides operating at constant frequency, all semiconductor devices operate at soft-swi...

Pourabbasali, Rogayeh; Freghi, Samira; Pourabbasali, Reza; Pakdel, Majid

55

Chaos, bifurcation and intermittent phenomena in DC-DC converters under resonant parametric perturbation  

Science.gov (United States)

DC-DC converters act as a black box to study various bifurcations. In the present study, the influence of external periodic interference signal in the input of DC-DC voltage-mode controlled buck converter has been considered. It is found that the presence of sinusoidal or saw-tooth interference signal whose frequency is comparable with the switching frequency of the converter or its rational multiples manifests as remerging chaotic band attractors (or Feigenbaum trees) and intermittent chaos. However, the presence of sinusoidal interference signal having irrational frequency ratios with the switching frequency of the converter leads to quasi-periodic route to chaos. The study was carried out both theoretically and experimentally.

Deivasundari, P.; Geetha, R.; Uma, G.; Murali, K.

2013-07-01

56

Two Point Four KW DC/DC Converter Regulator.  

Science.gov (United States)

The 2.4KW DC-DC Converter/Regulator Power Module furnishes 0-75ADC over an output voltage range of 24 to 32VDC from a nominal 20-40VDC unregulated power source and can be used for battery charging from 5 to 75A. Remote output voltage sensing at the load c...

R. E. Eggert

1981-01-01

57

Tertiary side resonant DC/DC converter with integrated magnetics  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a constant frequency tertiary side resonant dc/dc converter topology. The proposed converter topology gives the opportunity to integrate all the resonant inductors with the output transformer and provides greater flexibility in selecting the resonant capacitors. The harmonic equivalent circuit model and frequency domain analysis, which incorporates the effect of the leakage inductance of the high frequency transformer are presented. Steady state characteristics curves are presented to describe the effect of the leakage inductance and resonant circuit parameters on the performance of the converter. It is shown that with a tuned parallel resonant circuit on the tertiary winding the converter can be operated at higher frequencies. Finally, the experimental results show a higher than 80% efficiency for a 500 W, 48V to 5V dc/dc converter operating at 128 kHz.

Jain, P. [Concordia Univ., Montreal, Quebec (Canada); Jain, P.; Quaicoe, J. [Memorial Univ. of Newfoundland, St. John`s, Newfoundland (Canada)

1996-09-01

58

Sliding Mode Control of Dc-Dc Boost Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Control of Dc-Dc boost converter is a complex task due to the nonlinearity inherent in the converter and introduced by the external changes. A robust sliding mode controller for the control of Dc-Dc boost converter were described in this study. Dynamic equations describing the boost converter are derived and sliding mode controller is designed. The robustness of the sliding mode controlled boost converter system is tested for step load changes and input voltage variations. The computer-aided design software tool Matlab/Simulink is used for the simulations. The simulation results are presented. The simulation results show a fast dynamic response of the output voltage and robustness to load and input voltage variations.

Hanifi Guldemir

2005-01-01

59

Step-Up DC/DC Converters with the Tristate Quasi-Z-Source Network  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the Step-Up DC/DC Converters With The Tristate quasi- Z-Source Network. This paper is based on the step-up dc/dc converter family with a cascaded quasi-Z-source network. The tri-stage network could be derived by adding of one diode, one inductor, and two capacitors to the two quasi-Z-source inverter. It has advantages of Voltage boost and buck functions in a single stage, continuous input current and improved reliability. Theoretical analysis of the tri-stage quasi Z-Source network in the shoot-through and non-shoot-through operating modes is described. To further decrease the shoot-through duty cycle at the same voltage boost factor, the number of stages of the quasi Z-Source-network could be increased.

S. Diwahar; S. Surjith Barnala; N. Vikneswaran; M. Gurunathan

2013-01-01

60

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 filter size and currentsource characteristics. The Simulink circuit model for closed loop system of full bridgeDCDC converter VSWT is developed and the same is used for simulation studies.

M. Annamalai; M. Vijaya Kumar

2012-01-01

 
 
 
 
61

High efficiency interleaved bi-directional ZVS DC-DC converter  

Science.gov (United States)

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.

Zafarullah Khan, M.; Mohsin Naveed, M.; Akbar Hussain, D. M.

2013-06-01

62

Implementation of FPGA based Digital Controller for Controlling Chaos in DC/DC converters  

Directory of Open Access Journals (Sweden)

Full Text Available This paper analyzes the subharmonics andchaos generated in closed loop pulse width modulatedDC/DC buck converter and suggests the implementationof Digital controller based on time delayed selfcontrolling feedback concept for stabilizing the chaosgenerated in such converter. FPGA based digitalcontroller is designed and implemented for controllingthe chaotic oscillations of nonlinear switching converters.An experimental FPGA prototype and an applicationspecific IC that employ new controller architecture arebuilt around 11.3 V, 5.5 W, 2.5 KHz buck converter stageand successful operation of digital controller is verified.The experimental results prove the inherent capability ofthe proposed controller in maintaining the desired outputvoltage and keep the system chaos free by making thesystem insensitive to parameter variations.

LOGAMANI Premalatha; RANJAN Vanaja

2010-01-01

63

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

64

Design and implementation of fully-integrated inductive DC-DC converters in standard CMOS  

CERN Document Server

CMOS DC-DC Converters aims to provide a comprehensive dissertation on the matter of monolithic inductive Direct-Current to Direct-Current (DC-DC) converters. For this purpose seven chapters are defined which will allow the designer to gain specific knowledge on the design and implementation of monolithic inductive DC-DC converters, starting from the very basics.

Wens, Mike

2011-01-01

65

Radiated electromagnetic emissions of DC-DC converters  

CERN Multimedia

A new powering scheme is considered to be mandatory for the CMS tracker at SLHC. The baseline solution of CMS foresees the use of DC-DC converters, allowing to provide larger currents while reducing losses. An important component of most converters are inductors, which, however, tend to radiate the switching noise generated by the converter. The radiated emissions of several converters have been measured and simulated. In addition noise susceptibility measurements with radiated noise and present CMS hardware have been performed. A summary of the results will be presented.

Sammet, Jan Domenik

2010-01-01

66

Design of DC-DC Converter for Flash Memory IPs  

Directory of Open Access Journals (Sweden)

Full Text Available A DC-DC converter for flash memory IPs performing erasing by the FN (Fowler-Nordheim) tunneling and programming by the CHEI (channel hot electron injection) is designed in this paper. For the DC-DC converter for flash memory IPs using a dual voltage of VDD (=1.5V±0.15V)/VRD (=3.1V±0.1V), a scheme of using VRD (Read Voltage) instead of VDD is proposed to reduce the pumping stages and pumping capacitances of its charge pump circuit. VRD (=3.1V±0.1V) is a regulated voltage by a voltage regulator with an external voltage of 5V, which is used as the WL activation voltage in the read mode and an input voltage of the charge pump. The designed DC-DC converter outputs positive voltages of VP6V (=6V), VP8V (=8V) and VP9V(=9V); and a negative voltage of  VM8V (=-8V) in the write mode.

Li-yan Jin; Woo-Young Jung; Ji-Hye Jang; Min-Sung Kim; Myeong-Seok Kim; Heon Park; Pan-Bong Ha; Young-Hee Kim

2013-01-01

67

Distributed maximum power point tracking in photovoltaic applications: active bypass DC/DC converter/ Seguimiento del punto de máxima potencia distribuida en aplicaciones fotovoltaicas: convertidor DC/DC para desviación activa  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Se propone una estructura de desvío activo para maximizar la producción de potencia en sistemas fotovoltaicos bajo condiciones irregulares de operación, comparando su eficiencia con soluciones individuales y distribuidas basadas en convertidores DC/DC convencionales. Los análisis y simulaciones realistas demuestran las ventajas del nuevo convertidor de desvío activo sobre soluciones basadas en convertidores Boost, Buck y Buck-Boost. Abstract in english An active bypass structure is proposed to maximize the power production in photovoltaic modules under mismatched conditions. Its efficiency is compared with single and distributed maximum power point tracking solutions based on conventional DC/DC structures. The analysis and simulations performed under realistic assumptions demonstrate the benefits of the novel active bypass converter over solutions based on Boost, Buck or Buck-Boost converters.

Ramos-Paja, Carlos Andrés; Gira, Roberto; Arango Zuluaga, Eliana Isabel

2012-09-01

68

System Tests with DC-DC Converters for the CMS Silicon Strip Tracker at SLHC  

CERN Multimedia

The delivery of power is considered to be one of the major challenges for the upgrade of the CMS silicon strip tracker for SLHC. The inevitable increase in granularity and complexity of the device is expected to result in a power consumption comparable or even higher than the power consumption of todays' strip tracker. However, the space available for cables will remain the same. In addition, a further increase of the tracker material budget due to cables and cooling is considered inacceptable, as the performance of the CMS detector must not be compromised for the upgrade. Novel powering schemes such as serial powering or usage of DC-DC converters have been proposed to solve the problem. To test the second option, substructures of the current CMS silicon strip tracker have been operated for the first time with off-the-shelf DC-DC buck converters as well as with first prototypes of custom-designed DC-DC converters. The tests are described and the results are discussed.

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

2008-01-01

69

Chaotic Control Of A DC-DC-Converter  

UK PubMed Central (United Kingdom)

Recent publications on DC-DC-Converters have pointed outthat a chaotic operation mode may be of advantage for EMCreasons. This paper proposes a Boost-Converter scheme theswitching operation of which is controlled by a chaotic returnmap. A spectral analysis of the converter's input currentdemonstrates how the shape of the return map affects the powerdensity spectrum of the input current. This provides anapproach to solve the design problem, i.e. to choose a returnmap in order to meet particular spectral demands. Finally asimple circuit solution for the chaotic control of the converter isproposed.1. INTRODUCTIONDC-DC-Converters belong to the class of continuous-discretedynamical systems. They are known to exhibit chaotic behaviorand quite a lot of recent publications [e.g. 1-5] have beendevoted to the study of chaotic phenomena in this class ofcircuits. In [1] a statistical analysis of the input current of astandard boost-converter has been carried out. It turned out, ...

A. L. Baranovski; A. Mgel; W. Schwarz; O. Woywode; Technische Universitt Dresden; Fakultt Elektrotechnik

70

Three Level DC/DC Converter Using Energy Recovery Snubber  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a Zero Voltage and Zero Current Switching (ZVZCS) 3-Level DC/DC converter. This converter overcomes the drawbacks presented by the conventional Zero Voltage Switching(ZVS) 3-Level converter, such as high circulating energy, serve parastic ringing on the rectifier diodes, and limited ZVS load range for the inner switches. The converter presented in this paper uses a phase shift control with a flying capacitor in the primary side to achieve ZVS for the outer switches. Additionally, the converter uses an energy recovery snubber to reset the primary current during thr free-wheeling stage to achieve ZCS for thr inner switches. The proposed converters are analyzed and verified on 6kW, 30kHz experimental prototype. (author). 10 refs., 11 figs., 2 tabs.

Cho, Yong Hyun; Kim, Yoon Ho [Chungang University(Korea); Kim, Eun Soo [Korea Electrotechnology Research Institute (Korea)

2001-02-01

71

Application of digital control techniques for satellite medium power DC-DC converters  

Science.gov (United States)

The objective of this paper is to present a work concerning a digital control loop system for satellite medium power DC-DC converters that is done in Space Research Centre. The whole control process of a described power converter bases on a high speed digital signal processing. The paper presents a development of a FPGA digital controller for voltage mode stabilization that was implemented using VHDL. The described controllers are a classical digital PID controller and a bang-bang controller. The used converter for testing is a simple model of 5-20 W, 200 kHz buck power converter. A high resolution digital PWM approach is presented. Additionally a simple and effective solution of filtering of an analog-to-digital converter output is presented.

Skup, Konrad R.; Grudzinski, Pawel; Nowosielski, Witold; Orleanski, Piotr; Wawrzaszek, Roman

2010-06-01

72

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

73

Symmetrical dynamics of peak current-mode and valley current-mode controlled switching dc-dc converters with ramp compensation  

Science.gov (United States)

The discrete iterative map models of peak current-mode (PCM) and valley current-mode (VCM) controlled buck converters, boost converters, and buck-boost converters with ramp compensation are established and their dynamical behaviours are investigated by using the operation region, parameter space map, bifurcation diagram, and Lyapunov exponent spectrum. The research results indicate that ramp compensation extends the stable operation range of the PCM controlled switching dc-dc converter to D > 0.5 and that of the VCM controlled switching dc-dc converter to D VCM controlled switching dc-dc converters with ramp compensation exhibit interesting symmetrical dynamics. Experimental results are given to verify the analysis results in this paper.

Zhou, Guo-Hua; Xu, Jian-Ping; Bao, Bo-Cheng; Jin, Yan-Yan

2010-06-01

74

Artificial neural network control of sab dc/dc converter  

International Nuclear Information System (INIS)

The latest development of power semiconductor devices enable the modern power electronic converters to withstand high voltage and high power applications. Power electronic converters are mostly periodic variable structure systems due to their switched operations. The main drawback of these converters is the generation of oscillations which are developed during the operation of the converters under nonlinear situations. To handle these nonlinearities, various researchers have proposed different control techniques. Power electronic designers are devoting in the further development of converter topologies and their control techniques. SAB (Single Active Bridge) DC/DC converter is a new topology recently introduced by Demetriades. This topology is used in high voltage and high power applications. Because of its smart features, SAB converter has recently drawn attention of many researchers. However, during the operation of SAB converter severe oscillations are generated. In this research work, a novel NNC (Neural Network Controller) model is developed for SAB converter to minimize oscillations generated during its operation. NNC is believed to be an advanced nonlinear and robust controller which has the ability to map the nonlinear behaviour in a negligible response time. The performance of SAB converter with NNC is tested under dynamic region by considering the reference voltage variation and duty ratio variation. The SAB converter is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)

2009-01-01

75

Comparison of control structures for a bidirectional high-frequency dc-dc converter  

Science.gov (United States)

A system for dc-dc power conversion based on a buck-boost converter topology is presented. It makes power flow in both directions possible. The possibility of bidirectional power flow is useful for certain applications, such as uninterruptable power supplies. Starting from a structural diagram the transfer function of the system is derived. The controller for the converter is then designed. It is made up of a simple voltage controller, a voltage controller with an inner loop current controller (cascade control) and with two kinds of state space control. The transfer functions of the different system parts are derived and dimensioning guidelines for the controller sections are presented. The closed loop behavior of the bidirectional converter for the different control structures is analyzed based on simulation using duty cycle averaging. Bodediagrams and step responses are shown.

Himmelstoss, Felix A.; Kolar, Johann W.; Zach, Franz C.

1989-08-01

76

Microcomputer control of a current source dc-dc converter  

International Nuclear Information System (INIS)

A microcomputer-based time optimal control algorithm for a current source dc-dc converter is presented. The optimal control strategy for the system is shown to be bang-bang or maximum effort. The closed-loop bang-bang control was tested on a 22.4-kW energy transfer system. This system was the prototype of an inductor-converter bridge (ICB) at Argonne National Laboratory. The ICB is used for bidirectional (two-quadrant) energy transfer between two large superconducting coils. The system test setup and operation is presented in some detail. The test results of the control system are presented. The difference between the ideal and actual test results is analyzed in terms of accuracy, noise effects, quantization error, and instrumentation dynamic response. The results of this analysis are used for a systematic component specification of a microcomputer based bang-bang control system to achieve a required accuracy

1983-01-01

77

Simulation and Implementation of Quasi Resonant DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: A half-bridge LLC resonant converter with a voltage doubler rectifier has a simple structure and its Zero-Voltage-Switching (ZVS) capability is excellent from zero to full load condition. But conduction loss is more due to high circulating energy thus reducing the system efficiency. Moreover a variable frequency control method makes the control circuits more complicated than those using the Pulse Width Modulation (PWM) control method. Thus, DC drive has lower efficiency when it operates on light loads. Approach: To improve the efficiency of the DC drive under light loads, a PWM-controlled quasi-resonant converter is proposed .It has simple control circuits and less conduction loss compared to a half-bridge LLC resonant converter under light load conditions. The proposed converter has a half-bridge LLC resonant converter along with an auxiliary circuit. The load regulation of the proposed converter can be achieved by an auxiliary circuit. Thus the proposed converter is expected to be suitable sustaining power module for the efficiency enhancement of DC drives. As the magnetizing inductance of the proposed converter is larger the circulating energy is considerably reduced under light load conditions. In this study the operational principle, design and modeling of QRC DC-DC converters for DC drives are presented. The PWM controlled quasi resonant converter is implemented using PIC microcontroller 16F184A. Results: The capacitor filter in the output is replaced by pi filter to produce DC with minimum ripple. The experimental results and simulation results are compared. This converter has the advantages like reduced number of switches, reduced transformer and filter size, reduced ripple, reduced switching losses, reduced switching stresses and increased power density. Conclusion: The experimental results closely agree with the simulation results.

P. Parvathy; N. Devarajan

2012-01-01

78

A Novel Bidirectional DC-DC Converter With Flyback Snubber For Hybrid Electric Vehicles  

Directory of Open Access Journals (Sweden)

Full Text Available Hybrid electric Vehicles combine the benefits of engine, electric motor and batteries to provide improved fueleconomy. A converter is needed in hybrid Electric Vehicle for charging and discharging of the batteries. So a charging anddischarging can be combined in one circuit topology known as bidirectional DC-DC converter. Here the output is completelyisolated from input, so an isolated bidirectional Dc-DC converter is used. In the bidirectional DC-DC converter, there occursovervoltage and overcurrent stress, which can be reduced by snubber circuits. Various technologies such as RCD, active clampand flyback snubber for bidirectional DC-DC converter are compared. The bidirectional DC-DC converter with flyback snubberis explained in detail. The simulations are carried out using Simulink/MATLAB 7.6.0 (R2009b) package. The hardware is doneusing PIC16F877A, a microcontroller to generate the PWM pulses for the MOSFET switches so that harmonics in the circuit canbe reduced.

DIVYA K.NAIR; ELIZABETH RAJAN

2013-01-01

79

NPC four-quadrant DC-DC converter applying Integrated-Voltage-Control method; Den`atsu sekibunchi seigyo hoshiki wo mochiita NPC yonshogen DC-DC converter  

Energy Technology Data Exchange (ETDEWEB)

A switching mode DC-DC converter applying the Integrated-Voltage-Control method works stably and has no steady state error. The basic circuit of this converter consists of an error voltage integrator and a hysteresis comparator which drives a power transistor to on/off. The DC-DC converter circuit can be extended to a Four-Quadrant DC-DC converter circuit. This Four-Quadrant converter has four hysteresis comparators driven in parallel by an error voltage integrator, and each comparator drives a prearranged power transistor engaged with one of the four quadrants of the converter operation on the voltage- current plane. In this paper, we propose a new NPC (Neutral- Point- Clamped) Multi- Level Four- Quadrant DC-DC converter applying the Integrated-Voltage-Control method, developed from the Four-Quadrant DC-DC converter driving circuit. This new NPC converter consists of eight hysteresis comparators driven in parallel by an error voltage integrator. There are eight operating regions in this new converter and one of eight power transistors is driven by one of eight hysteresis comparators to on/off in each prearranged region. The neutral-point voltage can be kept at a constant value by a new restrain control scheme also proposed in this paper. It has been confirmed experimentally that the new NPC converter has no short circuit mode, no steady state error, and a quick response time. 11 refs., 12 figs., 2 tabs.

Okui, H. [Osaka Polytechnic College, Osaka (Japan); Irie, H. [Osaka Electro-Communication University, Osaka (Japan)

1998-02-01

80

High Power Zero-Voltage and Zero-Current Switching DC-DC Converters  

Directory of Open Access Journals (Sweden)

Full Text Available The paper presents principles and properties of the soft switching PWM DC-DC converters. The attention is focused mainly on high power applications and thus the full-bridge inverters are used in DC-DC converters. Considerations are also given to the control methods and principles of the switching and conduction losses reduction.

Jaroslav Dudrik

2005-01-01

 
 
 
 
81

High Power Density DC/DC Converter: Component Selection and Design.  

Science.gov (United States)

Further work pertaining to design considerations for the new high power, high frequency dc/dc converters is discussed. The goal of the project is the development of high power, high power density dc/dc converters at power levels in the multi-kilowatt to m...

D. M. Divan

1989-01-01

82

High power density dc/dc converter: Selection of converter topology  

Science.gov (United States)

The work involved in the identification and selection of a suitable converter topology is described. Three new dc/dc converter topologies are proposed: Phase-Shifted Single Active Bridge DC/DC Converter; Single Phase Dual Active Bridges DC/DC Converter; and Three Phase Dual Active Bridges DC/DC Converter (Topology C). The salient features of these topologies are: (1) All are minimal in structure, i.e., each consists of an input and output bridge, input and output filter and a transformer, all components essential for a high power dc/dc conversion process; (2) All devices of both the bridges can operate under near zero-voltage conditions, making possible a reduction of device switching losses and hence, an increase in switching frequency; (3) All circuits operate at a constant frequency, thus simplifying the task of the magnetic and filter elements; (4) Since, the leakage inductance of the transformer is used as the main current transfer element, problems associated with the diode reverse recovery are eliminated. Also, this mode of operation allows easy paralleling of multiple modules for extending the power capacity of the system; (5) All circuits are least sensitive to parasitic impedances, infact the parasitics are efficently utilized; and (6) The soft switching transitions, result in low electromagnetic interference. A detailed analysis of each topology was carried out. Based on the analysis, the various device and component ratings for each topology operating at an optimum point, and under the given specifications, are tabulated and discussed.

Divan, Deepakraj M.

1990-01-01

83

Optimization of DC-DC Converters for Improved Electromagnetic Compatibility With High Energy Physics Front-End Electronics  

CERN Multimedia

The upgrade of the Large Hadron Collider (LHC) experiments at CERN sets new challenges for the powering of the detectors. One of the powering schemes under study is based on DC-DC buck converters mounted on the front-end modules. The hard environmental conditions impose strict restrictions to the converters in terms of low volume, radiation and magnetic field tolerance. Furthermore, the noise emission of the switching converters must not affect the performance of the powered systems. A study of the sources and paths of noise of a synchronous buck converter has been made for identifying the critical parameters to reduce their emissions. As proof of principle, a converter was designed following the PCB layout considerations proposed and then used for powering a silicon strip module prototype for the ATLAS upgrade, in order to evaluate their compatibility.

Fuentes, C; Michelis, S; Blanchot, G; Allongue, B; Faccio, F; Orlandi, S; Kayal, M; Pontt, J

2011-01-01

84

Comparison Between Zvs and Zvs-Zcs Bidirectional Dc-Dc Converter Topologies  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper exhaustive comparative analysis has been done between a conventional ZVS converter and the ZVS-ZCS bidirectional DC-DC converters. A novel model of a bidirectional converter and its topology is introduced. The key working principles, functionality, simulation results are discussed and subsequently compared with the previous ZVS bidirectional converter system. With respect to switching losses, stresses and efficiency parameters the ZVS-ZCS bidirectional DC-DC converter is emphasized.

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

2010-01-01

85

Reconfigurable digital controller for a buck converter based on FPGA  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a complete digitally controlled dc-dc buck converter performed by FPGA circuitry. All tasks, analog to digital conversion, control algorithm and pulse width modulation, were implemented in the FPGA. This approach enables high-speed dynamic response and programmability by the cont...

Milanovi?, Miro; Trunti?, Mitja; Šlibar, Primož; Dolinar, Drago

86

Digital simulation and experimental testing of the resonant DC/DC converter  

Energy Technology Data Exchange (ETDEWEB)

This article is aimed to present both a simulation and experimental tests results of the resonant DC/DC converter. Described simulation algorithm has been used for design of the high voltage dc source applied for laser head supply. In the first part of the paper the schematic representation of the resonant dc/dc converter and control circuit are presented and described. In the second part, the mathematical model of converter by taking into account all its modes of operation is given. Presented mathematical description can be used for simulation and comparison of two basic circuits of the resonant converter: series-loaded resonant DC/DC converter (SLR) and parallel-loaded resonant dc/dc converter (PLR). (author). 14 figs.

Platek, T.; Niewiadomski, M.; Baranecki, A. [Politechnika Warszawska, Warsaw (Poland)

1994-12-01

87

Optimization with System Damping Restoration for Droop Controlled DC-DC Converters  

DEFF Research Database (Denmark)

The parallel operation of dc-dc converters is widely used in distribution systems and uninterruptable power supply systems. Droop control along with virtual resistance (VR) is considered a simple and reliable method for achieving wireless power sharing among converters. In order to enhance the efficiency of the conversion system, this paper implements tertiary level optimization control on the basis of hierarchical control. As the efficiency of each converter changes with output power, VRs are set as decision variables for adjusting power sharing proportion among converters. Genetic algorithm is used in searching for global efficiency optimum. However system dynamic is affected when shifting VRs. Therefore, the stability of a parallel buck converter system is analyzed to examine the influence of VR changing on system dynamics. Based on the stability analysis, a system damping secondary restoration (SDSR) is implemented to readjust the optimization results so as to ensure system stability. Simulation results are shown to demonstrate the improvement of system efficiency and effectiveness of the method.

Meng, Lexuan; Dragicevic, Tomislav

2013-01-01

88

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

89

Development of a green mode DC/DC converter available to portable nuclear instrument  

International Nuclear Information System (INIS)

A green mode DC/DC converter was developed which suitable to the portable nuclear instrument which is powered by battery and is sometime at stand-by mode. Some updated control approaches such as pseudo-resonant type power supply control and synchronous rectification were adopted to makethe DC/DC converter operate with low power consumption and high efficiency. The test results the battery can be prolonged with this converter. (authors)

2010-01-01

90

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.; Francisco R. Trejo-M.; Felipe Coyotl-M.; Rubén-T.; Hugo Romero-T.,

2013-01-01

91

Cryogenic Evaluation of an Advanced DC/DC Converter Module for Deep Space Applications.  

Science.gov (United States)

DC/DC converters are widely used in power management, conditioning, and control of space power systems. Deep space applications require electronics that withstand cryogenic temperature and meet a stringent radiation tolerance. In this work, the performanc...

M. E. Elbuluk A. Hammoud S. S. Gerber R. Patterson

2003-01-01

92

Control of the DC-DC Converter used into Energy Generation System  

International Nuclear Information System (INIS)

This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)

2006-01-01

93

Non-Dissipative Snubber for Rectifying Diodes in a High-Power DC-DC Converter  

Science.gov (United States)

In a high output current DC-DC converter, most power dissipation comes from rectifying diodes. In this paper, a novel non-dissipative snubber is proposed for the rectifying diodes to reduce the power dissipation of the rectifying circuit. This snubber is applied to the center-tapped rectifying circuit in a full-bridge DC-DC converter. As a result, the efficiency has been improved to 91% on the prototype of 12V/80A output.

Hirokawa, Masahiko; Ninomiya, Tamotsu

94

A digitally controlled PWM/PSM dual-mode DC/DC converter  

Science.gov (United States)

A digitally controlled pulse width modulation/pulse skip modulation (PWM/PSM) dual-mode buck DC/DC converter is proposed. Its operation mode can be automatically chosen as continuous conduction mode (CCM) or discontinuous conduction mode (DCM). The converter works in PSM at DCM and in 2 MHz PWM at CCM. Switching loss is reduced at a light load by skipping cycles. Thus high conversion efficiency is realized in a wide load current. The implementations of PWM control blocks, such as the ADC, the digital pulse width modulator (DPWM) and the loop compensator, and PSM control blocks are described in detail. The parameters of the loop compensator can be programmed for different external component values and switching frequencies, which is much more flexible than its analog rivals. The chip is manufactured in 0.13 ?m CMOS technology and the chip area is 1.21 mm2. Experimental results show that the conversion efficiency is high, being 90% at 200 mA and 67% at 20 mA. Meanwhile, the measured load step response shows that the proposed dual-mode converter has good stability.

Shaowei, Zhen; Bo, Zhang; Ping, Luo; Sijian, Hou; Jingxin, Ye; Xiao, Ma

2011-11-01

95

A digitally controlled PWM/PSM dual-mode DC/DC converter  

International Nuclear Information System (INIS)

A digitally controlled pulse width modulation/pulse skip modulation (PWM/PSM) dual-mode buck DC/DC converter is proposed. Its operation mode can be automatically chosen as continuous conduction mode (CCM) or discontinuous conduction mode (DCM). The converter works in PSM at DCM and in 2 MHz PWM at CCM. Switching loss is reduced at a light load by skipping cycles. Thus high conversion efficiency is realized in a wide load current. The implementations of PWM control blocks, such as the ADC, the digital pulse width modulator (DPWM) and the loop compensator, and PSM control blocks are described in detail. The parameters of the loop compensator can be programmed for different external component values and switching frequencies, which is much more flexible than its analog rivals. The chip is manufactured in 0.13 ?m CMOS technology and the chip area is 1.21 mm2. Experimental results show that the conversion efficiency is high, being 90% at 200 mA and 67% at 20 mA. Meanwhile, the measured load step response shows that the proposed dual-mode converter has good stability. (semiconductor integrated circuits)

2011-11-01

96

Superconducting energy stabilizer with charging and discharging DC-DC converters  

International Nuclear Information System (INIS)

This patent describes a superconducting energy stabilizer having multiple load connections and employing DC-DC conversion for storing energy in a superconducting inductive energy storage device having a first end and a second end, and for releasing the stored energy from the superconducting inductive energy storage device to a load or loads or to a utility or an industrial electrical distribution system, the superconducting energy stabilizer having multiple load connections and employing DC-DC conversion. It comprises: energy storage cell means for supplying energy to the load, discharging DC-DC converter means for releasing energy from the superconducting inductive energy storage device to the energy storage cell means, the discharging DC-DC converter means having input terminals, output terminals, and a discharging control line means for carrying signals controlling the operation of the discharging DC-DC converter means, one of the input terminals of the discharging DC-DC converter means coupled to the first end of the superconducting energy storage device

1991-06-19

97

Superconducting energy stabilizer with charging and discharging DC-DC converters  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a superconducting energy stabilizer having multiple load connections and employing DC-DC conversion for storing energy in a superconducting inductive energy storage device having a first end and a second end, and for releasing the stored energy from the superconducting inductive energy storage device to a load or loads or to a utility or an industrial electrical distribution system, the superconducting energy stabilizer having multiple load connections and employing DC-DC conversion. It comprises: energy storage cell means for supplying energy to the load, discharging DC-DC converter means for releasing energy from the superconducting inductive energy storage device to the energy storage cell means, the discharging DC-DC converter means having input terminals, output terminals, and a discharging control line means for carrying signals controlling the operation of the discharging DC-DC converter means, one of the input terminals of the discharging DC-DC converter means coupled to the first end of the superconducting energy storage device.

Kim, S.H.; Kostecki, E.L.; DeWinkel, C.C.

1992-10-27

98

Simulation and Implementation of Interleaved Boost DC-DC Converter for Fuel Cell Application  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with a boost dc-dc converter for fuel cell application. In fuel cell electric vehicles application, a high power boost dc-dc converter is adopted to adjust the output voltage, current and power of fuel cell engine to meet the vehicle requirements. One of challenge in designing a boost converter for high power application is how to handle the high current at the input side. In this paper an interleaved boost dc-dc converter is proposed for current sharing on high power application. Moreover, this converter also reduces the fuel ripple current. Performance of the interleaved boost converter is tested through simulation and experimental results. Keywords: component; Interleaved Boost Converter; Fuel Cell Electric Vehicle; high power application.  

Ahmad Saudi Samosir; NFN Taufiq; Abdul Halim Mohd Yatim

2011-01-01

99

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 cond...

Jaw-Kuen Shiau; Chien-Wei Ma

100

Efficient and ripple-mitigating dc-dc converter for residential fuel cell system  

Energy Technology Data Exchange (ETDEWEB)

Proton exchange membrane fuel cell (PEMFC) systems for residential application require efficient and ripple-mitigating power conditioning system (PCS). The key point to reach it, is the design and control of the dc-dc converter. Based on the theoretical and experimental analysis of the traditional converter, this paper proposes a novel parallel-series full bridge (P-SFB) dc-dc converter, and improves its phase shifting scheme. This paper also proposes a novel controller for low frequency ripple current suppressing applied on the converter. The experimental results verify that, the dc-dc converter achieves a peak efficiency of 95.5%. Therefore PCS's maximum efficiency reaches 92.9%. And the input current ripple is reduced significantly with the new controller. (author)

Wang, Yong [Danfoss Solar Inverters, Hardware, Jyllandsgade 28, 6400 Soenderborg (Denmark); Choi, Seeyoung [Digital Appliance Division, Samsung Electronics Co. Ltd., Maetan-3Dong, Suwon, Gyeonggi (Korea); Lee, Eunchul [Willings Co. Ltd., SK Ventium, 522 Dangjung-Dong, Gunpo-Si, Gyeonggi-Do (Korea)

2009-01-15

 
 
 
 
101

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.

102

DC-DC converters with reduced mass for trackers at the HL-LHC  

International Nuclear Information System (INIS)

The development at CERN of low noise DC-DC converters for the powering of front-end systems enables the implementation of efficient powering schemes for the physics experiments at the HL-LHC. Recent tests made on the ATLAS short strip tracker modules confirm the full electromagnetic compatibility of the DC-DC converter prototypes with front-end detectors. The integration of the converters in the trackers front-ends needs to address also the material budget constraints. The impact of the DC-DC converters onto the material budget of the ATLAS tracker modules is discussed and mass reduction techniques are explored, leading to a compromise between electromagnetic compatibility and mass. Low mass shield implementations and Aluminum core inductors are proposed. Also, the impact on emitted noise due to a size reduction of critical components is discussed. Finally, material reduction techniques are discussed at the board layout and manufacturing levels.

2011-01-01

103

Analysis of DC/DC Converter Efficiency for Energy Storage System Based on Bidirectional Fuel Cells  

DEFF Research Database (Denmark)

Renewable energy sources are fluctuating depending on the availability of the energy source. For this reason, energy storage is becoming more important and bidirectional fuel cells represent an attractive technology. Fuel cells require highcurrent low-voltage dc-dc or dc-ac converters as power interface to the grid. In power electronics, the converter efficiency is characterized at fixed operating voltage for various output power. This type of characterization is not suitable for fuel cells, since as the power from the fuel cell increases, the cell voltage decreases. This paper analyses how the fuel cell I-V characteristics influences the power electronics converter efficiency and their consequence on the overall system. A loaddependent efficiency curve is presented based on experimental results from a 6 kW dc-dc converter prototype including the most suitable control strategy which maximizes the dc-dc conversion efficiency.

Pittini, Riccardo; Zhang, Zhe

2013-01-01

104

A Reduced-Part, Triple-Voltage DC-DC Converter for Electric Vehicle Power Management  

Energy Technology Data Exchange (ETDEWEB)

Electrical power systems in future hybrid and fuel cell vehicles may consist of three voltage nets; 14 V, 42 V and high voltage (>200 V) buses. A soft-switched, bi-directional dc-dc converter using only four switches was proposed for interconnecting the three nets. This paper presents a reduced- part dc-dc converter, which decreases the converter cost while retaining all the favorable features of the original topology. Simulation and experimental data are included to verify a simple power flow control scheme.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2007-01-01

105

Elimination of output voltage oscillations in DC-DC converter using PWM with PI controller  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper the SIMULINK model of a PWM controlled DC-DC converter is modeled using switching function concept to control the speed of the DC motor. The presence of the voltage oscillation cycles due to higher switching frequency in the DC-DC converter is identified. The effect of these oscillations on the output voltage of the converter, Armature current, Developed torque and Speed of the DC motor is analyzed. In order to minimize the oscillation cycles the PI controller is proposed in the PWM controller.

Sreenivasappa Veeranna Bhupasandra; Udaykumar Yaragatti

2010-01-01

106

ZVS Bridge Leg and ZCS Bridge Leg DC-DC Converter with Tapped Inductor Filter  

Science.gov (United States)

In this paper, a novel full-bridge soft-switching phase-shifted PWM DC-DC power converter circuit is presented. A tapped inductor filter is implemented in the proposed converter topology to achieve soft switching commutation for the active power switches under wide load variation range, to minimize circulating current without using additional resonant circuit and/or auxiliary switching devices. The effectiveness of the proposed soft-switching DC-DC power converter is verified in experiment with 2kW-100kHz breadboard circuit using IGBTs.

Moisseev, Serguei; Hamada, Satoshi; Nakaoka, Mutsuo

107

Development of a fuzzy logic controller for dc/dc converters: Design, computer simulation, and experimental evaluation  

Energy Technology Data Exchange (ETDEWEB)

The design of a fuzzy logic controller for dc/dc converters is described in this paper. A brief review of fuzzy logic and its application to control is first given. Then, the derivation of a fuzzy control algorithm for regulating dc/dc converters is described in detail. The proposed fuzzy control is evaluated by computer simulations as well as experimental measurements of the closed-loop performance of simple dc/dc converters in respect of load regulation and line regulation.

So, W.C.; Tse, C.K.; Lee, Y.S. [Hong Kong Polytechnic Univ. (Hong Kong). Dept. of Electronic Engineering

1996-01-01

108

Double Two Switch Forward Soft Switching PWM DC-DC Converter  

Science.gov (United States)

A novel prototype of a double two-switch forward transformer linked zero-voltage and zero-current mode soft-switching (ZVZCS) pulse width modulation (PWM) DC-DC power converter using IGBTs for high power applications is presented. Based on a conventional two-switch forward transformer linked PWM DC-DC converter topology, this converter circuit configuration doesn't include any complex auxiliary resonant circuit. Combining two identical two-switch forward type DC-DC power conversion circuits with a tapped-inductor type DC smoothing filter into a power DC-DC conversion system makes it possible to achieve soft-switching conditions for the active power switches with aid of lossless snubber capacitors and transformer parasitic inductors. Lowered peak voltage across the power switching devices and their related peak current stresses, no transformer saturation effect, reducing of idle and circulating currents through circuit components are practically attained for this converter. This soft-switching PWM DC-DC power converter has some unique advantages such as better power conversion efficiency, lowered output DC ripple current, high power density, constant frequency PWM control scheme, cost effective and wide soft-switching operation range under load variations and PWM regulation settings for high power utilizations. The basic operating principle of the new soft switching power converter treated here is illustrated with approximate periodic steady-state circuit analysis for each mode equivalent circuit. The practical effectiveness of the proposed soft-switching DC-DC power converter is confirmed by the simulation results and is experimentally evaluated on basis of 500W-100kHz breadboard setup using the fast switching IGBTs.

Hamada, Satoshi; Moisseev, Serguei; Koudriavtsev, Oleg; Nakaoka, Mutsuo

109

Controlling DC-DC converters by chaos-based pulse width modulation to reduce EMI  

International Nuclear Information System (INIS)

In this paper, periodic and chaotic behaviors of DC-DC converters under certain parametric conditions are simulated, experimentally verified, and analyzed. Motivated by the work of J.H.B. Deane and D.C. Hamill in 1996, where chaotic phenomena are useful in suppressing electromagnetic interference (EMI) by adjusting the parameters of the DC-DC converter and making it operate in chaos, a chaos-based pulse width modulation (CPWM) is proposed to distribute the harmonics of the DC-DC converters continuously and evenly over a wide frequency range, thereby reducing the EMI. The output waves and spectral properties of the EMI are simulated and analyzed as the carrier frequency or amplitude changes with regard to different chaotic maps. Simulation and experimental results are given to illustrate the effectiveness of the proposed CPWM, which provides a good example of applying chaos theory in engineering practice.

2009-11-15

110

Optimized photovoltaic generator-water electrolyser coupling through a controlled DC-DC converter  

Energy Technology Data Exchange (ETDEWEB)

The coupling of a photovoltaic generator and an electrolyser is one of the most promising options for obtaining hydrogen from a renewable energy source. Both are well known technologies, however, since the high variability of the solar radiation, an efficient coupling still presents some challenges. Direct or through a DC-DC converter couplings are the options in isolated applications. In this work, three models, respectively, for a photovoltaic (PV) generator, a controlled DC-DC converter and a complete proton exchange membrane (PEM) electrolyser have been designed by using Matlab/Simulink. A PV-electrolyser specific algorithm to search for the optimum and safe working point for both elements is presented. Simulation results demonstrate that the use of a controlled DC-DC converter with the proposed algorithm shows better adaptability to the variable radiation conditions than the other coupling options. Therefore, it leads to a better compliance between the electrolyser and the sizing of the PV generator. (author)

Garcia-Valverde, R.; Miguel, C.; Urbina, A. [Universidad Politecnica de Cartagena, Departamento de Electronica, Tecnologia de Computadoras y Proyectos, Plaza del Hospital, 1, Cartagena, 30203 Murcia (Spain); Martinez-Bejar, R. [Universidad de Murcia, Departamento de Ingenieria de la Informacion y las Comunicaciones, Facultad de Informatica, Campus de Espinardo, 30071 Murcia (Spain)

2008-10-15

111

Neural-fuzzy control of DC-DC converters: An off-line learning approach  

Energy Technology Data Exchange (ETDEWEB)

Conventional linear frequency domain control methods fail to provide nonlinear control to cope with possible large variable fluctuation in DC-DC converters. Owing to the nonlinear behaviour, mainly provided by the fuzzy rules and membership functions of fuzzy logic, fuzzy logic control is a good alternative for controlling DC-DC converters. The problem of designing fuzzy logic controllers for DC-DC converters involves determining the fuzzy rules, the associated antecedent membership functions and consequent membership functions. This paper discusses the methodology of using neural networks to adjust the shapes and locations of the membership functions so that an optimal fuzzy control can be achieved. This method can eliminate the need for heavy computation in multi-variable control. (author). 10 figs., 12 refs.

So, W.C.; Tse, C.K. [Hong Kong Polytechnic, Kowloon (Hong Kong)

1995-12-31

112

Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit  

Directory of Open Access Journals (Sweden)

Full Text Available Auxiliary circuit for DC/DC converter withcontrolled output rectifier is presented in this paper.Soft switching for power switches of the inverter isachieved by using controlled output rectifier and softswitching of the controlled rectifier by using losslessauxiliary circuit. The principle of converter operationis explained and analyzed and experimental results onthe laboratory model are presented.

DUDRIK Jaroslav; BODOR Marcel; TRIP Daniel Nistor

2010-01-01

113

Soft switching bidirectional DC-DC converter for ultracapacitor-batteries interface  

International Nuclear Information System (INIS)

In this paper a new soft switching bidirectional DC-DC converter is introduced which can be applied as the interface circuit between ultracapacitors and batteries or fuel cells. All semiconductor devices in the proposed converter are soft switched while the control circuit remains PWM. Due to achieved soft switching condition, the energy conversion through the proposed converter is highly efficient. The proposed converter is analyzed and a prototype converter is implemented. The presented experimental results confirm the theoretical analysis.

2009-01-01

114

Soft switching bidirectional DC-DC converter for ultracapacitor-batteries interface  

Energy Technology Data Exchange (ETDEWEB)

In this paper a new soft switching bidirectional DC-DC converter is introduced which can be applied as the interface circuit between ultracapacitors and batteries or fuel cells. All semiconductor devices in the proposed converter are soft switched while the control circuit remains PWM. Due to achieved soft switching condition, the energy conversion through the proposed converter is highly efficient. The proposed converter is analyzed and a prototype converter is implemented. The presented experimental results confirm the theoretical analysis. (author)

Adib, Ehsan; Farzanehfard, Hosein [Dept. of Electrical and Computer Engineering, Isfahan Univ. of Technology (Iran)

2009-12-15

115

Analysis of RF conducted emission due to PWM and resonant DC-DC converters  

Energy Technology Data Exchange (ETDEWEB)

Analysis and modeling of common mode conducted ElectroMagnetic Interference (EMI) in the Radio Frequency (RF) range (10 KHZ--30MHZ) of a ZVT (DC-DC boost Zero Voltage Transition) PWM converter and a conventional PWM (DC-DC boost) converter are compared. Noise signal measurement is carried out by means of a LISN (Line Impedance Stabilization Network). To compute the noise spectrum of LISN output in RF range, direct simulation of equivalent noise circuits is implemented as well as an analysis in the frequency domain.

Mahdavi, J. [Sharif Univ. of Technology, Tehran (Iran, Islamic Republic of). Dept. of Electrical Engineering; Shahintabe, A. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Electrical Engineering; Farhadi, A. [Electric Power Research Center, Tehran (Iran, Islamic Republic of). Dept. of Electronics

1995-12-31

116

Design and Analysis of a Novel DC-DC Converter Fed from Multiple Voltage Sources  

Directory of Open Access Journals (Sweden)

Full Text Available A novel DC-DC converter is proposed in the work carried out powered from multiple sources. The power conversion circuit consists of less number of active power switches with associated passive components. By adjusting the duty-ratio of the active power switch, the power sharing between two power sources and proposed three sources; as well as the output voltage regulation can be made. The simulation and experimental results for conventional two sources and proposed three sources fed DC-DC converter are presented in this paper.

M.R.Rashmi; A.Suresh; T.NageswaraRao

2012-01-01

117

Using Nyquist or Nyquist-Like Plot to Predict Three Typical Instabilities in DC-DC Converters  

CERN Multimedia

By transforming an exact stability condition, a new Nyquist-like plot is proposed to predict occurrences of three typical instabilities in DC-DC converters. The three instabilities are saddle-node bifurcation (coexistence of multiple solutions), period-doubling bifurcation (subharmonic oscillation), and Neimark bifurcation (quasi-periodic oscillation). In a single plot, it accurately predicts whether an instability occurs and what type the instability is. The plot is equivalent to the Nyquist plot, and it is a useful design tool to avoid these instabilities. Nine examples are used to illustrate the accuracy of this new plot to predict instabilities in the buck or boost converter with fixed or variable switching frequency.

Fang, Chung-Chieh

2012-01-01

118

Modelling the buck-type converter transient response with pulsating load  

Science.gov (United States)

The analysis and modeling of buck type converters is described. Load variations are considered like any other variable in the system. Continuous time models which enable prediction of the transient response of the converter are proposed. Practical results are presented to validate analytical predictions derived from the model. The proposed method can be used in other dc-dc converter topologies.

Arau, J.; Cezon, J.; Aldana, F.; Uceda, J.

1989-08-01

119

A Novel DC-DC Boost Converter Design for Higher Conversion Efficiency  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the development of a DC-DC boost converter. In the proposed boost converter design, a passive regenerative snubber circuit is included to absorb the energy of stray inductance so as to reduce the IGBT switching losses. MATLAB simulation as well as an experiment results are conducted to validate the proposed device. The results show that the proposed boost converter design gives an efficiency of 93% which is better than the conventional converter (88%).

Samer AlSadi; Tamer Khatib

2012-01-01

120

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

 
 
 
 
121

A Comparison of Half Bridge & Full Bridge Isolated DC-DC Converters for Electrolysis Application  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a comparison of half bridgeand full bridge isolated, soft-switched, DC-DC converters forElectrolysis application. An electrolyser is a part of renewableenergy system which generates hydrogen from water electrolysisthat used in fuel cells. A DC-DC converter is required to coupleelectrolyser to system DC bus. The proposed DC-DC converter isrealized in both full-bridge and half-bridge topology in order toachieve zero voltage switching for the power switches and toregulate the output voltage. Switching losses are reduced by zerovoltage switching. Switching stresses are reduced by usingresonant inductor and capacitor. The proposed DC-DC converterhas advantages like high power density, low EMI, reducedswitching stresses, high circuit efficiency and stable outputvoltage. The MATLAB simulation results show that the output ofconverter is free from the ripples and regulated output voltage andthis type of converter can be used for electrolyser application .Experimental results are obtained from a MOSFET based DC-DCConverter with LC filter. The

R. Samuel Rajesh Babu; Joseph Henry

2011-01-01

122

Voltage Tracking of a DC-DC Flyback Converter Using Neural Network Control  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper proposes a neural network control scheme of a DC-DC Flyback converter that will step up a 12V DC and applied it on brushless DC motor with 12 and 24V dc. In this technique, a back propagation learning algorithm is derived. The controller is designed to track the output ...

Wahyu Mulyo Utomo; Sim Sy Yi; Yonis M.Y. Buswig; Afarul Abu Bakar; Md Zarafi Ahmad

123

A high voltage ratio and low ripple interleaved DC-DC converter for fuel cell applications.  

UK PubMed Central (United Kingdom)

This paper proposes a high voltage ratio and low ripple interleaved boost DC-DC converter, which can be used to reduce the output voltage ripple. This converter transfers the low DC voltage of fuel cell to high DC voltage in DC link. The structure of the converter is parallel with two voltage-doubler boost converters by interleaving their output voltages to reduce the voltage ripple ratio. Besides, it can lower the current stress for the switches and inductors in the system. First, the PSIM software was used to establish a proton exchange membrane fuel cell and a converter circuit model. The simulated and measured results of the fuel cell output characteristic curve are made to verify the correctness of the established simulation model. In addition, some experimental results are made to validate the effectiveness in improving output voltage ripple of the proposed high voltage ratio interleaved boost DC-DC converters.

Chang LY; Chao KH; Chang TC

2012-01-01

124

Saturable reactor assisted soft-switching PWM DC-DC converter. Kahowa reactor hojo soft switching PWM DC-DC converter  

Energy Technology Data Exchange (ETDEWEB)

This paper describes a new soft-switching PWM (pulse width modulation) full-bridge DC-DC converter which can overcome some of drawbacks by utilizing a small saturable reactor. The principle of operation and steady-state characteristics are presented. A role of the saturable reactor is also discussed. Moreover, the voltage and current stresses for active and passive components are mentioned. In order to verify the results, key experiments were conducted using a 350W, 500kHz prototype converter. Consequently, it was demonstrated that the converter achieves soft-switching in a wide load range without substantial increase in voltage and current stresses for active and passive components. From the merits and drawbacks of the present circuit system, this converter was found to have features of both conventional PWM converter and resonance type converter. 11 refs., 12 figs., 3 tabs.

Hamada, S. (Sansha Electric Mfg. Co. Ltd., Osaka (Japan)); Ogino, Y. (Osaka Institute of Technology, Osaka (Japan)); Nakaoka, M. (Kobe University, Kobe (Japan))

1992-12-20

125

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

2013-01-01

126

ZVZCS PWM DC-DC Converter with Energy Recovery Clamp  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents research motivated by industrial demand for special traction drive topology devoted tominimization of traction transformer weight against topology with classical 50Hz traction transformer. The special tractiondrive topology for AC power systems consists of input high voltage trolley converter (single phase matrix converter) –middle frequency transformer – output converter - traction motor has been described. The main attention has been given tothe control algorithm of the traction topology (inserting of NULL vector of matrix converter and Two-value control ofsecondary active rectifier).

Jaroslav Durdik; Vladimir Ruscin

2008-01-01

127

Current Fed Step-up DC/DC Converter for Fuel Cell Inverter Applications  

Science.gov (United States)

In order to use hydrogen fuel cells in domestic applications either as main power supply or backup source, their low DC output voltage has to be matched to the level and frequency of the utility grid AC voltage. Such power converter systems usually consist of a DC-DC converter and a DC-AC inverter. Comparison of different current fed step-up DC/DC converters is done in this paper and a double inductor step-up push-pull converter investigated, presenting simulation and experimental results. The converter is elaborated for 1200 W power to match the rated power of the proton exchange membrane (PEM) fuel cell located in hydrogen fuel cell research laboratory of Riga Technical University.

Andrei?iks, Aleksandrs; Vitols, Kristaps; Krievs, Oskars; Steiks, Ingars

2009-01-01

128

A New Soft-Switched Resonant DC-DC Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a new soft-switched resonant dcdc converter using a passive snubber circuit. The proposed converter uses a new zero voltage and zero current switching (ZVZCS) strategies to get ZVZCS function. Besides operating at constant frequency, all semiconductor devices operate at soft-swit...

Pourabbasali, Rogayeh; Freghi, Samira; Pourabbasali, Reza; Pakdel, Majid

129

A high frequency DC/DC converter for electric vehicles  

Energy Technology Data Exchange (ETDEWEB)

A full bridge converter using IGBTs [Insulated Gate Bipolar Transistors] at higher than normal frequencies is described. This approach is found to be cost effective for automotive applications since it provides a reasonable volume at a lower cost than other alternatives. Experimental results are included for a 1.5 kW converter operating at 40 kHz. 6 refs.

Masserant, B.J.; Stuart, T.A. [Toledo Univ., OH (United States)

1994-12-31

130

Optimization of the design of DC-DC converters for improving the electromagnetic compatibility with the Front-End electronic for the super Large Hadron Collider Trackers  

CERN Multimedia

The upgrade of the Large Hadron Collider (LHC) experiments at CERN sets new challenges for the powering of the detectors. One of the powering schemes under study is based on DC-DC buck converters mounted on the front-end modules. The hard environmental conditions impose strict restrictions to the converters in terms of low volume, radiation and magnetic field tolerance. Furthermore, the noise emission of the switching converters must not affect the performance of the powered systems. A study of the sources and paths of noise of a synchronous buck converter has been made for identifying the critical parameters to reduce their emissions. As proof of principle, a converter was designed following the PCB layout considerations proposed and then used for powering a silicon strip module prototype for the ATLAS upgrade, in order to evaluate their compatibility.

Fuentes Rojas, Cristian Alejandro; Blanchot, G

2011-01-01

131

DC-DC converter quasi-resonant for high powers using IGBT; Conversor DC-DC quase-ressonante para altas potencias utilizando IGBT  

Energy Technology Data Exchange (ETDEWEB)

This work is concerned to a BUCK quasi-resonant converter (QRC), with zero-current switching (ZCS), pulse-width modulation (PWM) regulated, for high power applications, and employing IGBT. An analysis of the BUCK-QRC-ZCS-PWM converter operation is made and the equations for its modelling are presented. 19 refs., 86 figs., 6 tabs.

Fernandes, Dilnei J.M.

1991-12-31

132

A suitable model plant for control of the set fuel cell-DC/DC converter  

Energy Technology Data Exchange (ETDEWEB)

In this work a state and transfer function model of the set made up of a proton exchange membrane (PEM) fuel cell and a DC/DC converter is developed. The set is modelled as a plant controlled by the converter duty cycle. In addition to allow setting the plant operating point at any point of its characteristic curve (two interesting points are maximum efficiency and maximum power points), this approach also allows the connection of the fuel cell to other energy generation and storage devices, given that, as they all usually share a single DC bus, a thorough control of the interconnected devices is required. First, the state and transfer function models of the fuel cell and the converter are obtained. Then, both models are related in order to achieve the fuel cell+DC/DC converter set (plant) model. The results of the theoretical developments are validated by simulation on a real fuel cell model. (author)

Andujar, J.M.; Segura, F.; Vasallo, M.J. [Departamento de Ingenieria Electronica, Sistemas Informaticos y Automatica, E.P.S. La Rabida, Universidad de Huelva, Ctra. Huelva - Palos de la Frontera, S/N, 21819 La Rabida - Palos de la Frontera Huelva (Spain)

2008-04-15

133

Improvement of burst-mode control of piezoelectric transformer based DC/DC converter  

Science.gov (United States)

Burst-mode operation is adopted sometimes in piezoelectric transformer based converters for two major purposes: (1) to achieve voltage regulation in DC/DC converters and (2) to achieve dimming control in backlight inverters. Burst-mode control enables the converter to operate at a constant switching frequency as well as to maintain good efficiency at light load conditions. However, in practice, the piezoelectric transformer cannot instantly stop vibrating in the burst-mode due to its high quality factor. The delay in the output voltage change resulting from this behavior influences the accuracy of the regulation. This paper proposes a control strategy to make the piezoelectric transformer stop more quickly so as to enhance the accuracy of burst-mode control. The proposed method only modifies the control signal of the burst-mode driving circuit. The proposed control strategy is verified by experiments in a step-down 9 W DC/DC converter.

Vasic, Dejan; Liu, Yuan-Ping; Schwander, Denis; Costa, François; Wu, Wen-Jong

2013-05-01

134

Soft-switching PWM DC-DC converter with reduced circulating current; Junkan denryu wo teigenshita soft switching PWM DC-DC converter  

Energy Technology Data Exchange (ETDEWEB)

Soft-switching phase-shifted PWM converters have been attracted much attention because of their low switching losses, constant frequency operation and simple control. However, a circulating current flows through the transformer and the primary bridge circuit during the freewheeling interval, resulting in relatively high current stresses for the transformer and switching devices compared with those of conventional hard-switching PWM converters. This paper presents an improved soft-switching PWM DC-DC converter which can substantially reduce the circulating current by employing a tapped inductor for output low-pass filter. The principle of operation and the role of the tapped inductor are illustrated. The effectiveness of the tapped inductor is evaluated through simulating analysis. Moreover, a 500W-100kHz prototype converter is implemented to demonstrate the excellent performances of both low switching and low conduction losses. 11 refs., 12 figs.

Hamada, S. [Sansha Electric Mfg. Co. Ltd., Osaka (Japan)

1996-01-20

135

dc-dc converter for charging a battery by means of a solar cell  

Energy Technology Data Exchange (ETDEWEB)

A dc-dc converter is described of the blocking oscillator type, for charging a battery from a solar cell. The use of a field effect transistor enables the oscillation to be started by the voltage from a single solar cell, even if the battery is fully exhausted. The overall efficiency of the circuit is improved by the use of the base-emitter junction of the switching transistor of the converter as rectifying element for the battery charging current.

Barre, C.

1981-06-16

136

Fast maximum power point control of current-fed DC-DC converter for photovoltaic arrays  

Energy Technology Data Exchange (ETDEWEB)

The design and operation of a modular current-fed DC-DC converter is described, together with the implementation of an algorithm for tracking the maximum power point of a photovoltaic array. The method utilises inherent features of the array current to obtain a fast control action. A novel test setup for the converter system has been developed, and test results are presented which show correct operation of the system with a response time of only a few milliseconds. (author)

Bleijs, J.A.M.; Gow, J.A. [University of Leicester (United Kingdom). Dept. of Engineering

2001-01-04

137

A Three-Phase Bidirectional DC-DC Converter for Automotive Applications  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a three-phase soft-switching, bidirectional dc-dc converter for high-power automotive applications. The converter employs dual three-phase active bridges and operates with a novel asymmetrical but fixed duty cycle for the top and bottom switches of each phase leg. Simulation and experimental data on a 6-kW prototype are included to verify the novel operating and power flow control principles.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2008-01-01

138

Pulse Skipping Modulated DC-DC Converter Modeling and Simulation  

Directory of Open Access Journals (Sweden)

Full Text Available Pulse Skipping Modulated converters havelow switching losses and are more efficient at lightloads than conventional PWM converters. A Buckconverter with Pulse Skipping Modulation controlwhereby pulses applied to the switch are blocked orreleased on output voltage crossing a predeterminedvalue is considered in this paper for applicationsinvolving sources with wide variations in voltage.Results of the study on the performance of regulatorcircuit are presented. The regulator workssatisfactorily over a wide input voltage range with goodtransient response but the ripple is found to be higher.Input current spectrum indicates a good EMIperformance but with crowding of components at lowfrequency range.

SRINIVASAN Ramamurthy; RANJAN Vanaja P

2010-01-01

139

A highly efficient PV system using a series connection of DC-DC converter output with a photovoltaic panel  

Energy Technology Data Exchange (ETDEWEB)

A photovoltaic (PV) power conditioning system (PCS) must have high conversion efficiency and low cost. Generally, a PV PCS uses either a single string converter or a multilevel module integrated converter (MIC). Each of these approaches has both advantages and disadvantages. For a high conversion efficiency and low cost PV module, a series connection of a module integrated DC-DC converter output with a photovoltaic panel was proposed. The output voltage of the PV panel is connected to the output capacitor of the fly-back converter. Thus, the converter output voltage is added to the output voltage of the PV panel. The isolated DC-DC converter generates only the difference voltage between the PV panel voltage and the required total output voltage. This method reduces the power level of the DC-DC converter and enhances energy conversion efficiency compared with a conventional DC-DC converter. (author)

Kim, Ho-sung [Department of Electrical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea); New and Renewable Energy System Research Center, Korea Electro-technology Research Institute, 28-1, Sungju-dong Changwon-si, Kyungsannam-do, 641-120 (Korea); Kim, Jong-Hyun; Min, Byung-Duk; Yoo, Dong-Wook [New and Renewable Energy System Research Center, Korea Electro-technology Research Institute, 28-1, Sungju-dong Changwon-si, Kyungsannam-do, 641-120 (Korea); Kim, Hee-Je [Department of Electrical Engineering, Pusan National University, Jangjeon-dong, Geumjeong-gu, Busan 609-735 (Korea)

2009-11-15

140

Statistical Analysis Of A DC-DC Converter  

UK PubMed Central (United Kingdom)

This paper describes the statistical analysis of a DC-DCBoost converter with chaotic behaviour. From the timefunction of the input current the embedded discrete mapis derived. First a statistical analysis of this discrete mapis carried out. The results obtained are then used todetermine the power density spectrum and the totalpower contained in the input current signal. It turns out,that this signal consists of a chaotic and a periodiccomponent. We calculate how the total AC powerdistributes between these two components. From theresults practical conclusions for the design as well as foEMC considerations can be drawn.1 BOOST CONVERTERThe converter circuit is depicted in Fig. 1. It generates aDC output voltage V o larger than the DC-input V i .Vi(t)comparator+-V oDRCSLQR SI Clocksignal TR-S-FlipflopFigure 1: Current Programmed PWM Boost ConverterIf the switch S is closed, the input current i(t) increasesuntil it reaches the adjustable reference value ...

Er L. Baranovski; Andreas Mgel; Wolfgang Schwarz; Oliver Woywode; Tu Dresden; Fakultt Elektrotechnik

 
 
 
 
141

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

142

5 kW DC/DC converter for hydrogen generation from photovoltaic sources  

Energy Technology Data Exchange (ETDEWEB)

This paper covers the design of a DC-DC power converter aimed for hydrogen production from photovoltaic sources. Power conditioning for such application is usually driven by different constraints: high step-down conversion ratio is required if the input voltage of such equipment has to be compatible with photovoltaic sources that are connected to grid-connected inverters; galvanic isolation; high efficiency and low mass. Taking into account those factors, this work proposes a push-pull DC/DC converter for power levels up to 5 kW. The operation and features of the converter are presented and analyzed. Design guidelines are suggested and experimental validation is also given. (author)

Garrigos, A.; Blanes, J.M.; Carrasco, J.A.; Lizan, J.L. [Area de Tecnologia Electronica, Universidad Miguel Hernandez de Elche, Avda. de la Universidad s/n, 03202 Elche, Alicante (Spain); Beneito, R. [AIJU, Avda. de la Industria 23, 03440 Ibi, Alicante (Spain); Molina, J.A. [Grupo SITEC, Calle Cadiz 38, Poligono Industrial L' Alfac III, 03440 Ibi, Alicante (Spain)

2010-06-15

143

Voltage Tracking of a DC-DC Flyback Converter Using Neural Network Control  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes a neural network control scheme of a DC-DC Flyback converter that will step up a 12V DC and applied it on brushless DC motor with 12 and 24V dc. In this technique, a back propagation learning algorithm is derived. The controller is designed to track the output voltage of the DC-DC converter and to improve performance of the Flyback converter during transient operations. Furthermore, to investigate the effectiveness of the proposed controller, some operations such as starting-up and reference voltage variations are verified. The numerical simulation results show that the proposed controller has a better performance compare to the conventional PI-Controller method.

Wahyu Mulyo Utomo; Sim Sy Yi; Yonis M.Y. Buswig; Afarul Abu Bakar; Md Zarafi Ahmad

2012-01-01

144

Modeling the Bi-directional DC-DC Converter for HEV's  

Directory of Open Access Journals (Sweden)

Full Text Available Hybrid Electrical Vehicles-HEV!?s are the importnt ways to improve vehicle performance. The transformer isolated bi-directional DC-DC converters are the key components of the traction system in HEV!?s. This paper presents adetail mathematic model of isolated bi-directional DC-DC converter for HEV!?s. Approximate models are important mathematic methods especially for analysis and closed-loop control design converter circuits.  These differential equations, which govern the converter operation, change periodically among a set of linear differential equations because of the switch effect. Basing on the time-scale the state variables was separate as fast-scale and slow-scale variables. The fast changing variable of the leakage inductor was eliminated by substitute the fast-scale variable into slow-scale variable equations, resulting in reduced order differential equations. From this set of  reduced orderdifferential equations the completely averaged model of the isolated DC/DC converter was derived. The simulated results reveal that the circuit and mathematical model are consistent very well. The averaged state variables can be treated as a small component plus a DC component, so the averaged model can be separated a dynamic small signal part and a DC part. This linearized small signal model is suit for control design and analysis at a steady point that is decided by the DC component. As an example a PI controller was design basing on the linear model.

Chongwu Wang; Xiangzhong Meng; Xiaowei Guo

2009-01-01

145

A DC-DC Converter Efficiency Model for System Level Analysis in Ultra Low Power Applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a model of inductor based DC-DC converters that can be used to study the impact of power management techniques such as dynamic voltage and frequency scaling (DVFS). System level power models of low power systems on chip (SoCs) and power management strategies cannot be correctly established without accounting for the associated overhead related to the DC-DC converters that provide regulated power to the system. The proposed model accurately predicts the efficiency of inductor based DC-DC converters with varying topologies and control schemes across a range of output voltage and current loads. It also accounts for the energy and timing overhead associated with the change in the operating condition of the regulator. Since modern SoCs employ power management techniques that vary the voltage and current loads seen by the converter, accurate modeling of the impact on the converter efficiency becomes critical. We use this model to compute the overall cost of two power distribution strategies for a SoC with multiple voltage islands. The proposed model helps us to obtain the energy benefits of a power management technique and can also be used as a basis for comparison between power management techniques or as a tool for design space exploration early in a SoC design cycle.

Aatmesh Shrivastava; Benton H. Calhoun

2013-01-01

146

Analysis and Experimental Results of Class E² dc/dc Converter Using Thinned-out Method  

UK PubMed Central (United Kingdom)

This paper presents the first analytical descriptionand experimental results of Class E2dc/dcconverter using thinned-out method. The results canbe used for designing a converter at any thinned-outratio and given condition. Performances of the converterare exactly calculated as functions of thinnedoutratio. The measured performance shows goodagreement with the analysis. In the circuit experimentdc/dc power conversion efficiency was over 86% at 1 MHz 5W.I. IntroductionResonant dc/dc converters have attracted a greatdeal of attention in recent years. They are able tooperate with high power conversion efficiency at highfrequencies. That realizes considerable miniaturizationof power supplies.Class E2dc/dc converter [1][2], which is one of thehigh-efficiency power sources, has ability to operateabove 1 MHz with high power conversion efficiency(more than 85 %). Class E2dc/dc converter is composedof a Class E inverter [3]-[7] and a Class E rectifier[8][10]. ...

Hirotaka Koizumi; Shinsaku Mori

147

Switched capacitor DC-DC converter ASICs for the upgraded LHC trackers  

International Nuclear Information System (INIS)

The High Luminosity Upgrade of the ATLAS Inner Tracker puts demanding requirements on the powering system of the silicon strip detector modules due to 10-fold increase of the channel count compared to the existing SemiConductor Tracker. Therefore, new solutions for the powering scheme must be elaborated. Currently two possible approaches, the serial powering and the parallel powering scheme using the DC-DC conversion technique, are under development. This paper describes two switched capacitor DC-DC converters designed in a 130 nm technology. For the optimized step-down converter, foreseen for the parallel powering scheme, power efficiency of 97% has been achieved, while for the charge pump, designed for the serial powering scheme, power efficiency of 85% has been achieved.

2010-01-01

148

Novel Soft Switching FB DC-DC Converter for Reducing Conduction Losses  

Energy Technology Data Exchange (ETDEWEB)

The conventional high frequency phase-shifted full bridge DC-DC converter has a disadvantage that a circulating current flows through transformer and switching devices during the freewheeling interval. Due to this circulating current, RMS current stress, conduction losses of transformer and switching devices are increased. To alleviate this problem, this study provides a novel circulating current free type high frequency soft switching phase-shifted full bridge DC-DC converter which applies the energy recovery snubber(ERS) attached at the secondary side of transformer. The ERS adopted in this study is consisted of three fast recovery diode(Ds1, Ds2, Ds3), two resonant capacitor(Cs1, Cs2) and a small resonant inductor ((Lr)) : It can be ignored because the transformer leakage inductance (L1) is able to use in stead of inserting the resonant inductor ((Lr)). (author). 7 refs., 6 figs.

Kim, Eun Soo; Kye, Moon Hoo; Joe, Kee Yeon [Korea Electrotechnology Research Institute (Korea, Republic of); Kim, Yoon Ho; Yoon, Byung Do [Chungang University (Korea, Republic of)

1998-02-01

149

Switched capacitor DC-DC converter ASICs for the upgraded LHC trackers  

CERN Multimedia

The High Luminosity Upgrade of the ATLAS Inner Tracker puts demanding requirements on the powering system of the silicon strip detector modules due to 10-fold increase of the channel count compared to the existing SemiConductor Tracker. Therefore, new solutions for the powering scheme must be elaborated. Currently two possible approaches, the serial powering and the parallel powering scheme using the DC-DC conversion technique, are under development. This paper describes two switched capacitor DC-DC converters designed in a 130 nm technology. For the optimized step-down converter, foreseen for the parallel powering scheme, power efficiency of 97% has been achieved, while for the charge pump, designed for the serial powering scheme, power efficiency of 85% has been achieved

Bochenek, M; Faccio, F; Michelis, S; 10.1088/1748-0221/5/12/C12031

2010-01-01

150

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

151

Very High Frequency Resonant DC/DC Converters for LED Lighting  

DEFF Research Database (Denmark)

This paper presents a very high frequency DC/DC converter for LED lighting. Several resonant topologies are compared and their usability discussed. At the end the resonant SEPIC converter is chosen based on the achievable power density and total bill of material. Simulations of a 51 MHz converter with 40 V input and 15 V output are made. The simulation shows possibility of achieving efficiency up to 87 % even with a HEXFET Power MOSFET. Three prototypes of the simulated converter are implemented showing good correlation with simulations. The prototypes have efficiencies up to 84 % and power densities up to 8.9 W/cm3 (146 W/in3).

Madsen, Mickey Pierre; Knott, Arnold

2013-01-01

152

Design considerations for very high frequency resonant mode dc/dc converters  

Science.gov (United States)

The demand for higher switching frequencies in power converters has rekindled interest in resonant mode topologies. Conventional resonant converter circuits, however, are not optimized for high-frequency operation. A new resoant mode dc/dc converter topology exhibits desirable characteristics including zero switching losses, elimination of snubbers, simple control strategy, and circuit operation that is insensitive to parasitics such as diode reverse recovery. Analysis and design techniques are discussed in detail and are experirmentally verified with a 150-W prototype converter operating in the frequency range 500 kHz-1 MHz.

Divan, Deepakraj M.

1987-01-01

153

Simulation Based Performance analysis of Active Clamp DHB ZVZCS Bidirectional DC-DC converter for Low Power Applications  

Directory of Open Access Journals (Sweden)

Full Text Available A novel active clamp dual half bridge DC/DC converter with bidirectional power flow is proposed in this paper and comparative analysis between active clamp DHB ZVZCS and ZVS-ZCS bidirectional DC-DC converter topologies is also presented. By adding active clamping circuits to both bridges, zero voltage and zero current switching are achieved to improve the performance of the bidirectional DC/DC converter. The principle of operation is analyzed and simulated. With the proposed active clamp ZVZCS concept, the MATLAB simulation results of the applications of the fuel cell and battery have been obtained and compared with those of ZVS-ZCS bidirectional converter. The simulation results of proposed converter is compared with the ZVS-ZCS bidirectional DC-DC converter, efficiency, switching losses are the key parameters compared.

V.V.Subrahmanya Kumar Bhajana

2012-01-01

154

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; S.G. Kadwane

2013-01-01

155

Inductor based switching DC-DC converter for low voltage power distribution in SLHC  

CERN Document Server

In view of a power distribution scheme compatible with the requirements of the SLHC environment, we are evaluating the feasibility of on-board inductor-based DC-DC step-down conversion. Such converter should be an integrated circuit and capable of operating in harsh radiation environments and in the high magnetic field of the experiments. In this paper we present results concerning the choice of the technology, the search for the magnetic components and the calculations of the expected efficiency.

Michelis, S; Marchioro, A; Kayal, M; PH-EP

2007-01-01

156

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.

Shahab H. A. Moghaddam; Ahmad Ayatollahi; Abdolreza Rahmati

2012-01-01

157

Immediate Analysis of Periodic Steady States in Switched DC-DC Converters via SPICE  

Directory of Open Access Journals (Sweden)

Full Text Available The method of immediate analysis of periodic steady states in switched DC-DC converters operating in the continuous current mode is described. The initial conditions, which correspond to the periodic steady state, are found in the first step. They are used consequently for the conventional transient analysis. A special SPICE model of the converter finds automatically these initial conditions, which are then available within the transient analysis. The method works both for the well-known behavioral models of switched converters and also for models which employ complex nonlinear SPICE models of semiconductor switches.

D. Biolek; V. Biolkova; Z. Kolka

2012-01-01

158

A DC-DC Conversion Powering Scheme for the CMS Phase-1 Pixel Upgrade  

CERN Multimedia

The powering scheme of the CMS pixel detector will be described, and the performance of prototype DC-DC buck converters will be presented, including power efficiency, system tests with DC-DC converters and pixel modules, thermal management, reliability at low temperature, and studies of potential frequency locking betwe...

Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Sammet, Jan Domenik; Wlochal, Michael

2012-01-01

159

Design and analysis of high frequency switched full-bridge dc-dc converter for ups in telecommunication applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper describes the design and implementation of high frequency switched full-bridge DC-DC converter using analog control techniques. The major aim of this paper is to provide constant DC voltage to each of the switching equipment of the telephone exchange. In general, all the telephone exchanges are having switching equipment to trace out the route or the communication path to the destination. The voltage to be fed to the switching equipment is obtained from the series connected batteries and is delivered to the DC-DC converter. The DC-DC converter consists of a ferrite transformer. The voltage from the battery is being stepped down by the ferrite transformer according to the requirement. Filters are employed to suppress the harmonics and noise contents in the output voltage. The voltage obtained from the DC-DC converter is controlled by the regulating pulse width modulator using PWM technique.

Mrs. K.Rajalakshmi#1 , Mr.S.P.Karthick

2013-01-01

160

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 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 about module’s high-efficiency performance. The detailed operating principles and steady-state analyses of continuous mode is described. A 15 volts produces from photovoltaic which is connects to high step-up dc-dc converter to produces output voltage of 170 volts. The novel proposed system is “an effective high step up interleaved dc-dc converter photovoltaic grid connection system”. In this configuration consists of PV array, high step-up interleaved dc-dc converter and three-phase inverter with grid connected system. In this system, the THD value per phase voltage of three phase inverter output without filter is 1.74% with grid connection system. In this same configuration with 2nd order filter connected of three phase inverter output, the THD value reduced to 0.08%. The results are shown in Matlab/simulink 2009a.

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

2013-01-01

 
 
 
 
161

SOFT-SWITCHED HIGH STEP-UP DC-DC CONVERTER WITH HIGH VOLTAGE GAIN  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a new design of soft switched high step-up dc-dc converter with high voltage gain which is suitable for high power applications such as Uninterruptible Power System (UPS), Photo Voltaic system and hybrid electric vehicles. The emergence of this front-end converter is to improve the shape of active input current given to the system. This converter proposes Soft-Switching technique to achieve ZVS turn on of active switches and ZCS turn off of diodes using Lr - Cr resonance in the auxiliary circuit. Therefore reduces the switching losses. Comparatively the voltage conversion ratio of this converter is higher when compared with the ordinary boost converter. Hence the voltage gain of this converter is also higher. A simulation platform is created using MATLAB which illustrates the ZVS and ZCS operation of the switches and diodes. Open loop and closed loop controlled converter systems are modelled and simulated.

J.C. PAUL IMMANUEL; D. ANITHA

2013-01-01

162

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

163

Light weight, high power, high voltage dc/dc converter technologies  

Science.gov (United States)

Power-conditioning weight reductions by orders of magnitude will be required to enable the megawatt-power-level space systems envisioned by the Strategic Defense Initiative, the Air Force, and NASA. An interagency program has been initiated to develop an 0.1-kg/kW dc/dc converter technology base for these future space applications. Three contractors are in the first phase of a competitive program to develop a megawatt dc/dc converter. Researchers at NASA Lewis Research Center are investigating innovative converter topology control. Three different converter subsystems based on square wave, resonant, and super-resonant topologies are being designed. The components required for the converter designs cover a wide array of technologies. Two different switches, one semiconductor and the other gas, are under development. Issues related to thermal management and material reliability for inductors, transformers, and capacitors are being investigated in order to maximize power density. A brief description of each of the concepts proposed to meet the goals of this program is presented.

Kraus, Robert; Myers, Ira; Baumann, Eric

164

Optimal use of DC/DC converters. Basic problems of potential separation and insulation strength; DC/DC-Wandler - richtig eingesetzt. Basis-Fragestellungen zum Thema Potentialtrennung und Isolationsfestigkeit  

Energy Technology Data Exchange (ETDEWEB)

The author discusses the optimal application of DC/DC converters. Insulation strength is one of the most important parameters. (orig.) [Deutsch] Die folgenden Ausfuehrungen geben die am haeufigsten gestellten Fragen von Schaltungsentwicklern in bezug auf den richtigen Einsatz von DC/DC-Wandlern wieder. Mit zu den wichtigsten Parametern zaehlt dabei die Isolationsfestigkeit. (orig.)

Hill, R. [Newport Components Ltd. (United Kingdom)

1997-07-22

165

A Novel ZVS Bidirectional DC-DC Converter for Fuel Cell Applications  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper a new bidirectional dc-dc converter for a fuel cell system is proposed that has a current tripler rectifier in its low voltage side. The converter is based on a ZVS half bridge topology with current tripler rectifier at the secondary side of transformer. The asymmetrical PWM is used in the converter to achieve ZVS of power switches and to regulate the output voltage at the desired value. The proposed converter has the advantages of high efficiency, high power density and simple circuit configuration. The operation principle and system analysis are described and discussed. Finally, the simulation results for the proposed converter are provided to verify the theoretical analysis.

A. Salami; E. Rezaei

2013-01-01

166

A Cascaded Quasi Z-Source Scheme Step up DC-DC Converter Using ANN Based Control.  

Directory of Open Access Journals (Sweden)

Full Text Available Modern renewable generation systems need smart and integrated power converters ensure for high efficiency of power conversion .This project intends to the Artificial Neural Network (ANN) based control step up DC-DC converter family with a cascaded Quasi Z-source network (qZS-scheme).The cascaded (two-stage) qZS- network could be derived by the adding of one diode, one inductor, and two capacitors to the traditional single stage quasi-Z-source inverter (qZSI). The proposed cascaded qZSI giving as same all the advantages of the traditional solution (voltage boost and buck functions in a single stage, continuous input current ,and improved reliability).As compared to the conventional qZSI, the proposed solution reduces the shoot-through duty cycle at the same voltage boost factor ,and without adding additional switches. The ANN based controller ensuring the better result compare to the conventional PI controller .The two-stage qZSI in the shoot-through and non-shoot-through operating modes are described. The proposed and conventional closed loop results are compared.

R.Praburaja; C.Karthikeyan

2013-01-01

167

Buck-Converter Photovoltaic Simulator  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a Photovoltaic Simulator Simulation using Buck Converter with analysis using bode diagram. A state space simulator model is derived to provide a detail non-linear model. The PV Static Model is modified by adding a low pass filter in order to avoid an algebraic loop prob...

Feri Yusivar; M. Y. Farabi; R. Suryadiningrat; W. W. Ananduta; Y. Syaifudin

168

Digital simulation of closed loop control of bi-directional dc - dc converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a closed loop control of isolated boost full bridge dc-dc converter for used in Medium and High power application. Zero voltage switching is applied in all switches. The dc inputvoltage is stepped up by using a boost converter. It is inverted using a fullbridge inverter. The transformer is used to produce a higher voltage in secondary voltage side The a.c. voltage is convertedinto d.c. voltage with the help of rectifier. The open loop model there is no possiblity of maintain a constant voltage with variation of input voltage. In closed loop system is maintain a constant voltage is applied with various value of input voltage. Matlab 7.3 version is used for simulating the open loop and closed loop full bridge dcdc converter are verified. Isolated boost converter can operate at an input voltage of 24V and the output voltage 200-260 V and average efficiency of 89% at 55khz switching frequency.

S.A. Elankurisil,; Dr.D.Sivakumar,; Dr. S.S. Dash

2011-01-01

169

Half bridge ZVS DC-DC converter with DCS PWM active clamp technique  

Directory of Open Access Journals (Sweden)

Full Text Available Half bridge (HB) dc–dc converter is an attractive topology for middle power level applications owing to its simplicity. This paper presents 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 one of the two 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, an active clamp branch comprising an auxiliary switch and a diode is added across the isolation transformer primary winding in the half bridge converter to achieve ZVS for the other main switch by utilizing energy stored in the transformer leakage inductance. Moreover, the auxiliary switch also operates at ZVS and ZCS conditions. In addition, the proposed topology with DCS PWM control eliminates the ringing resulting from the oscillation between the transformer leakage inductance and the switches junction capacitances during the off-time period. Therefore, the proposed converter has a potential to operate at higher efficiencies and switching frequencies.

JANAPATI SIVAVARA PRASAD

2012-01-01

170

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; S.THIRUMALIAH; G.HARITHA

2013-01-01

171

A Novel Soft Switching Full-Bridge PWM DC/DC Converter with Secondary Clamping Circuit  

Energy Technology Data Exchange (ETDEWEB)

This paper proposes a novel secondary clamping circuit for soft switching full-bridge PWM DC/DC converter. The proposed clamping circuit eliminates the reflecting current of the secondary side of the transformer so that reduce the conduction loss of the primary side of it during the freewheeling mode. Also, it ensures the zero-voltage/zero-current switching of the leading/lagging switches. The characteristics of the proposed clamping circuit are investigated and the validity is verified by the experimental results. (author). refs., figs.

Choo, Byeong Ho [Samsung Electronics Corporate Technical Operations (Korea, Republic of); Lee, Byoung Kuk; Yoo, Sang Bong; Hyun, Dong Seok [Hanyang University (Korea, Republic of)

1998-06-01

172

A Novel Secondary Clamping Circuit for Soft Switching Full-Bridge PWM DC/DC Converter  

Energy Technology Data Exchange (ETDEWEB)

This paper proposes a novel secondary clamping circuit for soft switching full-bridge PWM DC/DC converter. The proposed clamping circuit eliminates the reflecting current of the secondary side of the transformer so that reduce the conduction loss of the primary side of it during the freewheeling mode. Also, it ensures the zero-voltage/zero-current switching of the leading and the legging switches. The characteristics of the proposed clamping circuit are investigated and the validity is verified by the simulation results. (author). refs., figs.

Choo, B.H.; Lee, B.K.; Yoo, S.B.; Hyun, D.S. [Hanyang University (Korea, Republic of)

1997-04-01

173

The design of RF power supply using DC-DC converter  

International Nuclear Information System (INIS)

This paper proposes the design concept of a new RF power supply using DC-DC converters without large filter capacitors and crowbar circuits. The RF power supply is designed to get quite smoothness, fast turn off and on output characteristics. These characteristics are cleared with system simulation and a small experimental model. A 2MW (-100kV, 20A) power supply design is introduced and a view point of realization and total system efficiency are also discussed. 2 refs., 13 figs

1989-01-01

174

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

175

Fuzzy control of the DC-DC converter used as power interface for a fuel cell  

International Nuclear Information System (INIS)

In this paper it is analyzed a feed-forward fuzzy control for PWM control of the DC-DC converter using a fuel cell as energy source. For a dynamic load the fuel cell output voltage vary in large DC range and the high DC voltage stabilization can not be a difficult task. The advantages of the forward loop after the fuel cell output voltage concerning the stability and robustness of fuzzy control are compared with the best results obtained using a well designed proportional-integral control. The Simulink models for the used blocks, simulation results, and some design consideration are presented, too. (authors)

2007-01-01

176

A high-power high-voltage DC-DC converter for space applications  

Energy Technology Data Exchange (ETDEWEB)

The design details of a modular dc-dc converter used to power the main anode supply of a mercury-iron motor are presented. This motor, the RIT-35 built by Messerschmitt-Bolkow-Blohm (MBB), Germany, is used as the propulsion unit of a future Asteroid Gravity Optical and Radar Analysis (AGORA) mission. The design selected to cope with the high-voltage high-power conversion for space applications is shown, as well as the requirement to operate from an unregulated solar array with a voltage excursion of from 150 V at beginning-of-mission (BOM) to 240 V at end-of-mission (EOM).

Weinberg, A.H.; Schreuders, J.

1986-07-01

177

A high power high voltage dc/dc converter for space applications  

Science.gov (United States)

The design details of a modular dc/dc converter used to power the main anode supply of a mercury ion motor are presented. This motor, the RIT-35 built by M.B.B. Germany, is used as the propulsion unit of a future Asteroid Gravity Optical and Radar Analysis (AGORA) mission. This paper shows the design selected to cope with the high voltage, high power conversion for space applications and the requirement to operate from an unregulated solar array with a voltage excursion of from 150 volts beginning-of-mission (BOM) to 240 volts end-of-mission (EOM).

Weinberg, A.; Schreuders, J.

178

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

179

A new current-fed, isolated PWM dc-dc converter  

Energy Technology Data Exchange (ETDEWEB)

This paper introduces a new current-fed dc-dc power converter circuit whose features are as follows: two active switches gated in a complementary and asymmetrical way, connected to the same ground; inherent high reliability provided by the input boost inductor; isolation by a high-frequency transformer; and output filter purely capacitive. Circuit operation, theoretical analysis, and design procedure are presented. Experimental results taken from a prototype, rated at 48 V/300 W, are also included in the paper to demonstrate the validity of the theoretical analysis.

Mantovanelli, P.; Barbi, I. [Federal Univ. of Santa Catarina, Florianopolis, Santa Catarina (Brazil)

1996-05-01

180

High-Frequency Soft-Switching DC-DC Converters for Voltage and Current DC Power Sources  

Directory of Open Access Journals (Sweden)

Full Text Available The paper presents soft switching PWM DC-DC converters using powerMOSFETs and IGBTs. The attention is focused mainly on the full-bridge converterssuitable for high power applications. The properties of the PWM converters are describedin comparison to other categories of soft switching converters. An overview of theswitching techniques using in the DC-DC converters is included. Considerations are alsogiven to the control methods. The principles of the switching and conduction lossesreduction in the PWM converters are illustrated. Various types of snubber circuits arementioned and their operation and limitations are discussed.

Jaroslav Dudrik; Juraj Oetter

2007-01-01

 
 
 
 
181

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

182

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

183

Asymmetrical Interleaved DC/DC Switching Converters for Photovoltaic and Fuel Cell Applications—Part 1: Circuit Generation, Analysis and Design   

Directory of Open Access Journals (Sweden)

Full Text Available A novel asymmetrical interleaved dc/dc switching converters family intended for photovoltaic and fuel cell applications is presented in this paper. The main requirements on such applications are small ripples in the generator and load, as well as high voltage conversion ratio. Therefore, interleaved structures and voltage multiplier cells have been asymmetrically combined to generate new converters, which inherently operate indiscontinuous conduction mode. The novel family is derived from boost, buck-boost and flyback-based structures. This converter family is analyzed to obtain the design equations and synthesize a design process based on the typical requirements of photovoltaic and fuel cell applications. Finally, the experimental results validate the characteristics and usefulness of the asymmetrical interleaved converter family. 

Eliana Arango; Carlos Andres Ramos-Paja; Javier Calvente; Roberto Giral; Sergio Serna

2012-01-01

184

A DC-DC converter based powering scheme for the upgrade of the CMS pixel detector  

International Nuclear Information System (INIS)

Around 2016, the pixel detector of the CMS experiment will be upgraded. The amount of current that has to be provided to the front-end electronics is expected to increase by a factor of two. Since the space available for cables is limited, this would imply unacceptable power losses in the currently installed supply cables. Therefore it is foreseen to place DC-DC converters close to the front-end electronics, allowing the provision of power at higher voltages, thereby facilitating the supply of the required currents with the present cable plant. This conference report introduces the foreseen powering scheme of the pixel upgrade. For the first time, system tests have been conducted with pixel barrel sensor modules, radiation tolerant DC-DC converters and the full power supply chain of the pixel detector. In addition, studies of the stability of different powering schemes under various conditions are summarized. In particular the impact of large and fast load variations, which are related to the bunch structure of the LHC beam, has been studied.

2011-01-01

185

Variable-capacity air-conditioning system with DC-DC converter power supply  

Energy Technology Data Exchange (ETDEWEB)

To date, room temperature control in rolling stock has been performed by means of a thermostat switching the air conditioner power source on and off. Accordingly, there is a large temperature difference between the two conditions resulting in a decreased comfort level for the passengers. In order to improve the performance characteristics, a development on the variable-capacity air conditioning system for rolling stock was carried out. The temperatures of inside and outside the rolling stock are detected by sensor together with the inside humidity, the temperature difference between pre-settled comfortable condition and measured one is calculated, then required power is provided to the rolling stock from DC current source. The variable-capacity air conditioning is carried out with a variable-voltage variable-frequency (VVVF) inverter together with an on-board DC-DC converter power system. A blower inverter and a compressor inverter are built in the air conditioning system, the variable-capacity operation is performed through a controlling command. The main output of DC-DC converter is DC 330 V, others are two circuits of DC and three circuits of AC. 5 figures, 2 tables.

Onishi, Toshiyuki; Kira, Hirotada; Nakashima, Kunihiro

1988-10-01

186

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

187

Double layer capacitor/DC-DC converter system applied to constant power loads  

Energy Technology Data Exchange (ETDEWEB)

Ultracapacitors or double layer capacitors are a recent technology based on the well-known electrochemical phenomenon of extremely high capacitance/unit area in an electrode-electrolyte interface and the high surface area achievable in activated carbon fibers. Capacitors have been tested with a rated capacitance value of 470 F and a rated voltage of 2.3 V. Test voltages as high as 3V (30% above rated) have been used without any short term effect on measured capacitance. At 3 V the total energy storage capacity of one capacitor is 2,100 Joules. With a total volume of 245 cm{sup 3}, the specific energy of this capacitor is 8.5 J/cm{sup 3}. To tap this entire energy store would require running the capacitor to zero voltage. Of course, few loads to which a capacitor bank might be connected can tolerate any drop in input voltage. To remedy this problem a DC/DC converter between the capacitor bank and load is proposed. This paper describes optimization of capacitor bank configurations when supplying a constant power load through a DC/DC converter.

Spyker, R.L.; Nelms, R.M. [Auburn Univ., AL (United States). Dept. of Electrical Engineering

1996-12-31

188

Parallel-Connected Solar Photovoltaic with Ultra Low Voltage DC/DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available In series-connected wiring scheme, the residual energy generated by partially shaded cells cannot be collected or, worse, impedes collection of power from the remaining fully illuminated cells. In this paper, a parallel-connected topology is introduced to PV panel. Each cell, connected to the dc bus paralleled with a special converter, is treated as a voltage source. The dc-dc converter is introduced to realize the method, which could work under an ultra-low-voltage (ULV). Efficiency comparison is discussed with a valid calculation. Experiments about the converter, PV cell and the parallel-connected panel are given. The results show that the novel system has a good working characteristic and the efficiency is higher than that of the conventional.

Zhiwen Yu; Da Xie; Junqi Feng

2013-01-01

189

Design of a total-dose radiation hardened monolithic CMOS DC-DC boost converter  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the design and implementation of a monolithic CMOS DC-DC boost converter that is hardened for total dose radiation. In order to improve its radiation tolerant abilities, circuit-level and device-level RHBD (radiation-hardening by design) techniques were employed. Adaptive slope compensation was used to improve the inherent instability. The H-gate MOS transistors, annular gate MOS transistors and guard rings were applied to reduce the impact of total ionizing dose. A boost converter was fabricated by a standard commercial 0.35 {mu}m CMOS process. The hardened design converter can work properly in a wide range of total dose radiation environments, with increasing total dose radiation. The efficiency is not as strongly affected by the total dose radiation and so does the leakage performance. (semiconductor integrated circuits)

Liu Zhi; Yu Hongbo; Liu Youbao [Xi' an Institute of Microelectronics Technology, Xi' an 710054 (China); Ning Hongying, E-mail: liuzhi6048@126.com [Xi' an University of Technology, Xi' an 710048 (China)

2011-07-15

190

Design of a total-dose radiation hardened monolithic CMOS DC-DC boost converter  

International Nuclear Information System (INIS)

This paper presents the design and implementation of a monolithic CMOS DC-DC boost converter that is hardened for total dose radiation. In order to improve its radiation tolerant abilities, circuit-level and device-level RHBD (radiation-hardening by design) techniques were employed. Adaptive slope compensation was used to improve the inherent instability. The H-gate MOS transistors, annular gate MOS transistors and guard rings were applied to reduce the impact of total ionizing dose. A boost converter was fabricated by a standard commercial 0.35 ?m CMOS process. The hardened design converter can work properly in a wide range of total dose radiation environments, with increasing total dose radiation. The efficiency is not as strongly affected by the total dose radiation and so does the leakage performance. (semiconductor integrated circuits)

2011-01-01

191

Systematic design approach of fuzzy PID stabilizer for DC-DC converters  

International Nuclear Information System (INIS)

DC-DC converters process electrical energy by switching between a fixed number of configurations. The objective of controlling these systems is to provide better performances, ensure closed loop stability and guarantee a simple predictable behaviour. Based on a converter averaged model, we propose, in this paper, a systematic design approach of a fuzzy PID. The choice of controller parameters stands on the whole system stability requirements. Extension of the obtained asymptotic stability to structural stability is presented to show that the developed controller ensures also a simple and predictable behaviour of the converter. Finally, we illustrate the efficiency of the proposed fuzzy PID design approach through simulations in voltage mode as well as in current mode control.

2008-01-01

192

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; K.Sowjanya; P.Raghavendran

2013-01-01

193

Evaluación de control neuronal con arquitectura óptima para convertidor DC/DC Evaluating neural control with optimal architecture for DC/DC converter  

Directory of Open Access Journals (Sweden)

Full Text Available El control de convertidores DC/DC, topologías utilizadas ampliamente en la reducción activa de contenido armónico para equi- po monofásico no lineal de baja potencia, plantea grandes retos de diseño debido a lo complejo del modelo matemático y su característica dinámica altamente no lineal. Técnicas de inteligencia artificial como las redes neuronales, suponen grandes me- joras en el diseño y desempeño final, dada su capacidad de aprender dinámicas complejas y generalizar su comportamiento. La motivación de este trabajo fue la de plantear (y posteriormente evaluar la respuesta dinámica) un lazo de control directo con re- des neuronales, que permitiera adicionalmente eliminar elementos de prueba y error en su diseño. Se propone un control direc- to basado en red neuronal artificial, cuyo diseño se realizó de forma óptima utilizando modelos de búsqueda bioinspirada, esto para optimizar simultáneamente dos aspectos diferentes pero fundamentales de la red: la arquitectura y los pesos de las cone- xiones. El control es aplicado a un convertidor boost. Los resultados obtenidos permiten observar el desempeño dinámico del es- quema, para el cual los tiempos de respuesta y los delta de voltaje en la salida permiten concluir que los criterios seleccionados para el diseño del control son apropiados y representan un aporte en el desarrollo de aplicaciones de control de sistemas con- mutados DC/DC.Controlling DC/DC converters (topologies widely used in the active reduction of harmonic content for single-phase nonlinear low -power equipment) raises great design challenges due to the mathematical model’s complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final per- formance, given their capacity for learning complex dynamics and generalising their behaviour. This work was aimed at propo- sing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test ele- ments and error in its design. Artificial neuronal network-based direct control was designed as well as possible using bio-inspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme’s dynamic performan- ce; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of DC/DC switchmode systems.

Martínez Sarmiento Fredy Hernán; Castiblanco Ortíz Mariela

2009-01-01

194

Evaluación de control neuronal con arquitectura óptima para convertidor DC/DC/ Evaluating neural control with optimal architecture for DC/DC converter  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish El control de convertidores DC/DC, topologías utilizadas ampliamente en la reducción activa de contenido armónico para equipo monofásico no lineal de baja potencia, plantea grandes retos de diseño debido a lo complejo del modelo matemático y su característica dinámica altamente no lineal. Técnicas de inteligencia artificial como las redes neuronales, suponen grandes mejoras en el diseño y desempeño final, dada su capacidad de aprender dinámicas complejas y gen (more) eralizar su comportamiento. La motivación de este trabajo fue la de plantear (y posteriormente evaluar la respuesta dinámica) un lazo de control directo con redes neuronales, que permitiera adicionalmente eliminar elementos de prueba y error en su diseño. Se propone un control directo basado en red neuronal artificial, cuyo diseño se realizó de forma óptima utilizando modelos de búsqueda bioinspirada, esto para optimizar simultáneamente dos aspectos diferentes pero fundamentales de la red: la arquitectura y los pesos de las conexiones. El control es aplicado a un convertidor boost. Los resultados obtenidos permiten observar el desempeño dinámico del esquema, para el cual los tiempos de respuesta y los delta de voltaje en la salida permiten concluir que los criterios seleccionados para el diseño del control son apropiados y representan un aporte en el desarrollo de aplicaciones de control de sistemas conmutados DC/DC. Abstract in english Controlling DC/DC converters (topologies widely used in the active reduction of harmonic content for singlephase nonlinear low power equipment) raises great design challenges due to the mathematical model's complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final performance, given their capacity for learning complex dynamics and generalising their behaviour. (more) This work was aimed at proposing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test elements and error in its design. Artificial neuronal networkbased direct control was designed as well as possible using bioinspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme's dynamic performance; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of DC/DC switchmode systems.

Martínez Sarmiento, Fredy Hernán; Castiblanco Ortíz, Mariela

2009-12-01

195

A Stable Control Strategy for Input-Series Output-Series Connected Boost half Bridge DC-DC Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Boost half bridge DC-DC converters in the combination of an input-series and output-series (ISOS) connected configuration with a stable control strategy has been investigated in this paper. A stable control strategy comprises of two loops that are current loop and voltage loop. The reference to the current loop has been chosen from the input side of the DC-DC converter. The reference to the voltage loop has been selected from the output side of the DC-DC converter. Such a reference makes the circuit configuration simple, easy and eventually results in reduced cost. The control strategy for input-series output-series (ISOS) configuration of DC-DC converters is proposed to achieve equal input voltage sharing (IVS) as well output voltage sharing (OVS). Furthermore, in this paper, the performance of the stable control strategy for input-series output-series (ISOS) boost half bridge DC-DC converter has been observed not only for the fixed but also for the varying and continuously varying load. The proposed Stable control scheme has been developed by modeling it on MATLAB using Simulink and Simpower toolboxes. The operation of the proposed stable control strategy has been found to be satisfactory.

Amir Mahmood Soomro; Amjad Ali Syed; Shahnawaz Farhan Khahro; Xiaozhong Liao; Farhan Manzoor

2013-01-01

196

Buck-Converter Photovoltaic Simulator  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a Photovoltaic Simulator Simulation using Buck Converter with analysis using bode diagram. A state space simulator model is derived to provide a detail non-linear model. The PV Static Model is modified by adding a low pass filter in order to avoid an algebraic loop problem and able to analyze easier. PV simulator is realized by controlling buck converter’s current using PI Controller with reference from PV model. Then the model is linearized which is used for analysis purpose. The system is analyzed using bode diagram for its output voltage against its inputs of solar irradiance and cell’s temperature. The Load, Proportional Gain Kp, and Integral Gain Ki are varied to observe their effects into the system stability. It is noticed that the limits of gain stability system are so high at all values of load and gains so the Buck-Converter Photovoltaic Simulator, which is proposed here, can be declared as a robust system.

Feri Yusivar; M. Y. Farabi; R. Suryadiningrat; W. W. Ananduta; Y. Syaifudin

2011-01-01

197

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

198

A Reduced-Part, Triple-Voltage DC-DC Converter for EV/HEV Power Management  

Energy Technology Data Exchange (ETDEWEB)

Electrical power systems in future hybrid and fuel cell vehicles may consist of three voltage nets: 14 V, 42 V, and high voltage (>200 V) buses. A soft-switched, bidirectional dc-dc converter that uses only four switches was proposed for interconnecting the three nets. This paper presents a reduced-part dc-dc converter, which decreases the converter cost while retaining all the favorable features of the original topology. Experimental data are included to verify a simple power flow control scheme.

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2009-01-01

199

A Three Level ZVZCS Phase-Shifted DC/DC Converter Using A Tapped Inductor And A Snubber Capacitor  

Energy Technology Data Exchange (ETDEWEB)

The conventional three-level high frequency phase-shifted dc/dc converter has a disadvantage that a circulating current flows through transformer and switching devices during the freewheeling interval. Due to this circulating current and RMS current stress, conduction losses of transformer and switching devices increases. To alleviate these problems, we propose an improved three-level Zero Voltage and Zero Current Switching (ZVZCS) dc/dc converter using a tapped inductor, a snubber capacitor and two snubber diodes attached at the secondary side of transformer. The proposed ZVZCS converter in verified on a 7kW, 30Hz experimental prototype. (author). 5 refs., 9 figs.

Kim, Eun Soo [Korea Electrotechnology Research Institute (Korea); Kim, Yoon Ho [Chungang University (Korea)

2001-04-01

200

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 systems need the current most. Thus, unbalanced currents of the grid line have been minimized and the reliability and performance of the DER grid connected system has been increased. A detailed mathematical analysis of the converter under steady state and transient condition are presented. Mathematical models for boost and buck modes are being derived and the simulink model is constructed in order to simulate the system. Moreover, the model has been validated on the actual operation of the converter, showing that the simulated results in Matlab Simulink are consistent with the experimental ones.

Ambrosio B. Cultura II; Ziyad M. Salameh

2012-01-01

 
 
 
 
201

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

2013-01-01

202

Bifurcation Boundary Conditions for Switching DC-DC Converters Under Constant On-Time Control  

CERN Multimedia

Sampled-data analysis and harmonic balance analysis are applied to analyze switching DC-DC converters under constant on-time control. Design-oriented boundary conditions for the period-doubling bifurcation and the saddle-node bifurcation are derived. The required ramp slope to avoid the bifurcations and the assigned pole locations associated with the ramp are also derived. The derived boundary conditions are more general and accurate than those recently obtained. Those recently obtained boundary conditions become special cases under the general modeling approach presented in this paper. Different analyses give different perspectives on the system dynamics and complement each other. Under the sampled-data analysis, the boundary conditions are expressed in terms of signal slopes and the ramp slope. Under the harmonic balance analysis, the boundary conditions are expressed in terms of signal harmonics. The derived boundary conditions are useful for a designer to design a converter to avoid the occurrence of the ...

Fang, Chung-Chieh

2012-01-01

203

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 method have adaptive ability to disturbances, and overcome the limitation on non-singular terminal sliding mode control scheme caused by disturbance boundary value. Simulation results show the validity of this adaptive non-singular terminal sliding mode control approach.

FAN, L.; YU, Y.

2011-01-01

204

Conventional control and fuzzy control of a dc-dc converter for machine drive  

Energy Technology Data Exchange (ETDEWEB)

Fuzzy logic or fuzzy set theory is recently getting increasing emphasis in process control applications. The paper describes an application of fuzzy logic in speed control system that uses a dc-dc converter. The fuzzy control is used to linearize the family of external characteristics of the converter in discontinuous-conduction mode occurring at light load and/or high speed. In order to compare the conventional control with the fuzzy logic control, algorithms have been developed in detail and verified by Microsoft Excel simulation. The simulation study indicates that fuzzy control is a good alternative for conventional control methods, being used particularly in non-linear complex systems ill defined or totally unknown. Where the mathematical model exists, it is useful. The applications of fuzzy set theory in power electronics are almost entirely new; fuzzy logic seems to have a lot of premises in the large industrial control field. (orig.) 2 refs.

Radoi, C.; Florescu, A. [Department of Power Electronics `Politecnica` University Bucharest (Romania)

1997-12-31

205

An improved soft switching PWM FB DC/DC converter for reducing conduction Losses  

Energy Technology Data Exchange (ETDEWEB)

An improved soft switching topology of a full bridge PWM dc/dc converter is described. The new topology employs an the energy recovery snubber to minimize a circulating current flowing through the transformer and switching devices. By using an energy recovery snubber instead of adding a tapped inductor and a saturable reactor to reduce RMS current stress, the converter achieves nearly zero current switching for the right leg due to the minimized circulating current, and achieves zero voltage switching for the left leg due to the reflected output current during the interval of left leg transition. An analysis and experiments are performed to verify the proposed topology by implementing a 12.5 kWh (125 VDC, 100 A), 30 Khz IGBT based experimental circuit. (author). 6 refs., 6 figs.

Kim, E.S.; Joe, K.Y.; Kye, M.H. [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of); Yoon, B.D.; Kim, Y.H. [Chung-Ang University, Seoul (Korea, Republic of)

1995-12-01

206

A Novel Half-Bridge Asymmetrical ZCS-PWM DC-DC Converter with High Frequency-Link  

Science.gov (United States)

A novel zero current soft-switching (ZCS)-PWM cell-assisted half-bridge DC-DC converter topology with a high frequency link is proposed in this paper. The newly-proposed DC-DC converter consists of a PWM-controlled single-ended half-bridge high frequency (HF) inverter and a current doubler rectifier linked with a HF transformer. In order to attain the wide range of ZCS-PWM operation in the primary-side HF inverter, an active edge resonant snubber cell composed by a switched capacitor and a lossless inductor is adopted in the half-bridge leg, providing ZCS commutation for a wide range of output power. The operation characteristics of the DC-DC converter proposed here are described, and its feasibility data is demonstrated and evaluated with simulation and experimental results.

Mishima, Tomokazu; Hiraki, Eiji; Tanaka, Toshihiko; Nakaoka, Mutsuo

207

Dynamic analysis of the input-controlled buck converter fed by a photovoltaic array  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O controle da tensão de entrada de conversores DC-DC é freqüentemente necessário em aplicações com energia fotovoltaica. Nesta situação especial, diferentemente do que ocorre com conversores convencionais, a tensão de saída é constante e a tensão de entrada é variável. Este artigo versa sobre a análise e o controle do conversor buck com tensão de saída constante e tensão de entrada variável. Abstract in english The control of the input voltage of DC-DC converters is frequently required in photovoltaic applications. In this special situation, unlike conventional converters, the output voltage is constant and the input voltage is controlled. This paper deals with the analysis and the control of the buck converter with constant output voltage and variable input.

Villalva, Marcelo Gradella; Ruppert Filho, Ernesto

2008-12-01

208

Dynamic analysis of the input-controlled buck converter fed by a photovoltaic array  

Directory of Open Access Journals (Sweden)

Full Text Available The control of the input voltage of DC-DC converters is frequently required in photovoltaic applications. In this special situation, unlike conventional converters, the output voltage is constant and the input voltage is controlled. This paper deals with the analysis and the control of the buck converter with constant output voltage and variable input.O controle da tensão de entrada de conversores DC-DC é freqüentemente necessário em aplicações com energia fotovoltaica. Nesta situação especial, diferentemente do que ocorre com conversores convencionais, a tensão de saída é constante e a tensão de entrada é variável. Este artigo versa sobre a análise e o controle do conversor buck com tensão de saída constante e tensão de entrada variável.

Marcelo Gradella Villalva; Ernesto Ruppert Filho

2008-01-01

209

Design and Implementation of Coaxial Winding Transformers for Isolated DC-DC Converters  

Science.gov (United States)

High power isolated DC/DC converters have been extensively used in various applications. Significant research efforts have been devoted to increase the operating efficiency and power density of the converter. Soft switching full bridge converter has been proposed to meet these goals by establishing zero voltage switching condition across the power transistors. However, a significant inductor is required to facilitate the resonance condition, and results in increased loss and reduced power density of the converter. In this article, a full bridge converter with limited soft switching capability (1)-(3) and a coaxially-wound transformer are presented to improve the power density. With the coaxial winding structure, the coupling coefficient the transformer will be much higher than conventional transformer, and result in small leakage inductance. The duty cycle loss of the converter is also reduced thanks to the low leakage inductance of the coaxial transformer. Various coaxial structures are presented in this paper Detailed simulations using Ansoft are conducted to observe their magnetic characteristics. These coaxial transformers are constructed in the laboratory and tested with the full bridge converter under soft-switching conditions to evaluate the performance of the entire system.

Cheng, Po-Tai; Yang, Siang-Yu; Guan, Yeh; Wang, Shinn-Shyong

210

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

2012-01-01

211

A Zero-Voltage and Zero-Current Switching Full Bridge DC-DC Converter for Arc Welding Machines  

Energy Technology Data Exchange (ETDEWEB)

A new welding machine which adopts zero voltage and zero current switching (ZVZCS) full bridge (FB) DC-DC converter is proposed. The proposed ZVZCS FB DC-DC converter uses auxiliary transformer to obtain ZCS for leading leg. It has capability of controlling load current even in short circuit condition and is suitable for arc welding machines. The power rating of the auxiliary transformer is about one 5th to one 10th of the main transformer. Experimental results for 10KW prototype are shown to verify the principle of operation. (author). 4 refs., 13 figs., 1 tab.

Jeon, Seong Jeub [Pukyong National University (Korea)

1999-06-01

212

A dual VCDL DLL based gate driver for zero-voltage-switching DC-DC converter  

International Nuclear Information System (INIS)

This paper presents a dual voltage-controlled-delay-line (VCDL) delay-lock-loop (DLL) based gate driver for a zero-voltage-switching (ZVS) DC-DC converter. Using the delay difference of two VCDLs for the dead time control, the dual VCDL DLL is able to implement ZVS control with high accuracy while keeping good linearity performance of the DLL and low power consumption. The design is implemented in the CSM 2P4M 0.35 ?m CMOS process. The measurement results indicate that an efficiency improvement of 2%-4% is achieved over the load current range from 100 to 600 mA at 4 MHz switching frequency with 3.3 V input and 1.3 V output voltage.

2010-01-01

213

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

214

Resonant Boost Dc-Dc Converter for a High Frequency Operation  

Directory of Open Access Journals (Sweden)

Full Text Available With different versions of inverters available, a control of VHF resonant boost dc-dc converter is described in detailed in this paper. Though, a classical Class- ? inverter is well documented in the literature, this is a new version and coupled to resonant rectifier. The twin aspect of any design of resonant boost topology is to mainly feature low device voltage stress and to have high efficiency over wide range of loads. Increased switching frequency allows smaller size of the passive components, allowing one to use air-core magnetic, and thereby reducing core loss. The output is regulated by MPPT controller. The performance analysis was carried out on MATLAB/Simulink platform and performance characteristics are presented along with the values of components.

Tejaswini R,

2013-01-01

215

Enhancing Detectability of Bifurcations in DC-DC Converters by Stochastic Resonance  

UK PubMed Central (United Kingdom)

Noise-driven systems tend to display special featuresin their power spectra when approaching bifurcation orinstability. These features, called noisy precursors, canbe of significant use since they can serve as a warningsignal for the impending loss of stability. Anotherphenomenon that has received significant attention inthe mathematical physics and biology literature is thatof stochastic resonance. In stochastic resonance, thesignal-to-noise ratio (SNR) is nonmonotonic with respectto noise level. This cannot occur in linear systems.Most past studies of stochastic resonance involvebistable systems with a weak external periodic forcing.However, recently the same basic phenomenon has beenobserved in autonomous systems operating along a limitcycle. In any case, the combination of precursors andstochastic resonance provides a tool for instability monitoring.In this paper, these observations are appliedto a discrete-time DC-DC converter model. Precursorsof period doubling ...

Priya Ranjan; Eyad H. Abed

216

POWER CIRCUITRY FOR AN IMPLANTABLE MEDICAL DEVICE USING A DC-DC CONVERTER  

UK PubMed Central (United Kingdom)

Improved power circuitry for charging a battery in an implantable medical device is disclosed. The improved power circuitry uses a DC-DC converter positioned between the rectifier and the battery in the implant to be charged, and operates to boost the voltage produced by the rectifier to a higher compliance voltage used to charge the battery. Because the rectifier can now produce a smaller DC voltage, the AC voltage preceding the rectifier (the coil voltage), can also be lessened. Lowering the coil voltage reduces the amount of heat generated by the coil, which reduces the overall heat generated by the implant during receipt of a magnetic charging field from an external charger during a charging session, which improves patient safety. Additionally, a reduced coil voltage means that the external charger can reduce the intensity of the magnetic charging field, which also reduces heat generated in the external charger during the charging session.

WHITEHURST TODD; CARBUNARU RAFAEL; PARRAMON JORDI

217

Power Circuitry for an Implantable Medical Device Using a DC-DC Converter  

UK PubMed Central (United Kingdom)

Improved power circuitry for charging a battery in an implantable medical device is disclosed. The improved power circuitry uses a DC-DC converter positioned between the rectifier and the battery in the implant to be charged, and operates to boost the voltage produced by the rectifier to a higher compliance voltage used to charge the battery. Because the rectifier can now produce a smaller DC voltage, the AC voltage preceding the rectifier (the coil voltage), can also be lessened. Lowering the coil voltage reduces the amount of heat generated by the coil, which reduces the overall heat generated by the implant during receipt of a magnetic charging field from an external charger during a charging session, which improves patient safety. Additionally, a reduced coil voltage means that the external charger can reduce the intensity of the magnetic charging field, which also reduces heat generated in the external charger during the charging session.

WHITEHURST TODD; CARBUNARU RAFAEL; PARRAMON JORDI

218

Analysis of Class D-E Resonant dc/dc Converter Using Thinned-out Method  

UK PubMed Central (United Kingdom)

Previous analytical descriptions of the Class D-Eresonant dc/dc converter using thinned-out methodhave been based on the assumptions simplifyingthe effect of thinned-out control on the equivalentimpedance. Therefore the difference betweenthe calculated values and the measured values issignificant in large thinned-out ratio. This paperpresents a new analysis for this circuit. The equivalentimpedance's variation by thinned-out controlis taken into consideration. The measured performanceshows good agreement with the analyticalperformance in wide range.1 IntroductionClass D inverter [1] is one of valuable high-densitypower sources because of the high dc/ac power conversionefficiency which is achieved by their lowswitching losses at several hundred kHz, furthermoreClass D inverter has also low switch devicevoltage stresses, equal to the dc input voltage.Class E rectifiers have been introduced in[2]. These circuits also offer high-frequency highefficiencylow-noise rec...

Hirotaka Koizumi; Shinsaku Mori

219

Bifurcation diagram features of a dc-dc converter under current-mode control  

International Nuclear Information System (INIS)

A common tool for analysis of the systems dynamics when the system has chaotic behaviour is the bifurcation diagram. In this paper, the bifurcation diagram of an ideal model of a dc-dc converter under current-mode control is analysed. Algebraic relations that give the critical points locations and describe the pattern of the bifurcation diagram are derived. It is shown that these simple algebraic and geometrical relations are responsible for the complex pattern of the bifurcation diagrams in such circuits. More explanation about the previously observed properties and introduction of some new ones are exposited. In addition, a new three-dimensional bifurcation diagram that can give better imagination of the parameters role is introduced

2006-01-01

220

A Novel Two Switch Non-inverting Buck-Boost Converter based Maximum Power Point Tracking System  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A solar module can’t transfer maximum power to the load itself due to impedance mismatch. A maximum power point tracking (MPPT) system could be employed to have the maximum power.  A new MPPT system has been developed using Buck-Boost type DC-DC converter. The system is highly efficient and robust. ...

Khandker Tawfique Ahmed; Mithun Datta; Nur Mohammad

 
 
 
 
221

Analysis and design of a saturable reactor assisted soft-switching full-bridge dc-dc converter  

Energy Technology Data Exchange (ETDEWEB)

Analysis and design considerations for a saturable reactor assisted soft-switching full-bridge dc-dc converter are presented. The converter has advantages such as low switching losses with no substantial increase in conduction losses, wide load range, and constant frequency operation. To show how to utilize the analysis results, a 350-W, 500-kHz converter is chosen as a design example. The results are verified experimentally on a prototype converter.

Hamada, Satoshi (Sansha Electric Manufacturing Co., Ltd., Osaka (Japan)); Nakaoka, Mutsuo (Kobe Univ. (Japan). Dept. of Electrical and Electronics Engineering)

1994-05-01

222

Practical Evaluations of a Novel Asymmetrical ZCS-PWM DC-DC Converter with High-Frequency Transformer-Link  

Science.gov (United States)

This paper presents a novel Zero Current Switching (ZCS)-PWM controlled half-bridge DC-DC converter with High-Frequency (HF)-link. The newly-proposed soft switching DC-DC converter consists of a multi-resonant half-bridge HF-isolated inverter controlled by an asymmetrical PWM scheme and a center-tapped diode rectifier with a choke input filter. In order to attain the wide range of soft-commutation under the condition of constant switching frequency, the single Active Edge-Resonant Cell (AERC) that is composed of a lossless inductor and a switched resonant capacitor is originally employed for the half-bridge inverter arm, providing and assisting ZCS operations in the switching power devices. The ZCS-PWMDC-DC converter treated here is evaluated in experiments using the 800 W-55 kHz prototype. The practical effectiveness of the proposed soft switching DC-DC converter is actually demonstrated and discussed with the experimental results under open loop and closed loop configurations. Finally, the feasibility of the DC-DC converter topology is discussed from the view points of the high efficiency and high power density.

Mishima, Tomokazu; Hiraki, Eiji; Nakaoka, Mutsuo

223

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

224

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; Vuchev Stoyanov Aleksandar

2012-01-01

225

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 ...

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

226

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...

Ambrosio B. Cultura II; Ziyad M. Salameh

227

Basic circuits to design switched-based DC-DC converters  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this paper is twofold. On one hand, basics on switched circuits for designing a DC-DC converter are presented and, on the other hand, power electronics definitions associated with simple electrical networks are mentioned. In the analysis of these networks, it is necessary to take into account not only converters' non-idealities but also how to minimize power losses. Since power losses may be minimized by increasing the clock frequency of switched-based converters, experimental results of basic clock generators are presented. These generators were implemented with low-cost componentsEl 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; J.R Mercado-Moreno; L.H Urióstegui-Vázquez

2007-01-01

228

A Protection Circuit for DC-DC Converter with Voltage Doubler  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes a method to obtain a protected voltage gain by employing a protection circuit for the voltage doubler or multiplier circuit in an isolated tyde DC-DC Converter. The entire set up consists of a phase shift converter with a protected bridge/voltage doubler rectifier on the output side. The operating frequency of the phase shift converter is 20-25kHz (depending on the requirement of the application) which is high enough to improve the efficiency. Ferrite core transformer is used in place of ordinary air core transformer, which is small in size with number of turns of the transformer is reduced and the overall power density is increased. The doubler circuit consists of electrolytic capacitors, which are rated at 400V in order to comply with IEC65 requirements. This paper proposes an “electrolytic capacitor protection circuit”, which enables the voltage rating of the electrolytics to be reduced to 250V. This circuit results in cost savings of more than 50% in the price of the electrolytic filter capacitors. The circuits were simulated using PSPICE SOFTWARE and the following results were obtained. For an input voltage of 200V, an output of 200V and400V were obtained in bridge mode and doubler mode respectively.

D.Elangovan; A.Gopi; Dr.R.Saravanakumar

2012-01-01

229

Design and Simulation of a soft switching scheme for a dc-dc Boost Converter with pi controller  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the design of simple but powerful soft switching scheme for a DC-DC Boost Converter with a closed loop control. A new novel soft switching scheme is proposed with a single switch and minimum components which offers load independent operations. The only switch used in this converter is switched ON at zero current and switched OFF at zero voltage .The proposed Controller is used to improve the dynamic performance of DC-DC converter by achieving a robust output voltage against load disturbances. The duty cycle of the Boost converter is controlled by PI Controller. A 50W/50KHz soft switched PWM Boost converter is simulated and analyzed. The results are simulated using PSIM

X.Felix Joseph; S.Pushpa Kumar; D.Arun Dominic; D.M.Mary Synthia Regis Prabha

2010-01-01

230

An imroved design for ZVT DC-DC PWM converters with snubber assisted auxiliary switch  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Este artigo propõe uma metodologia de projeto aprimorada para determinação dos componentes auxiliares para o conversor ZVT CC-CC PWM snubber assisted auxiliary switch. O procedimento de projeto proposto é baseado na redução das perdas de condução no circuito auxiliar. Isto é somente possível devido à localização do capacitor snubber de bloqueio, o qual é compartilhado por ambas as chaves ativas. Através do procedimento de projeto proposto o rendimento do co (more) nversor pode ser aumentado. Uma análise comparativa do rendimento é apresentada e os resultados experimentais, obtidos de protótipos de laboratório de 1 kW, 100 kHz, mostram uma melhoria relevante em relação ao rendimento apresentado pelo projeto original. Além disso, os resultados experimentais também confirmam que o projeto proposto para o conversor ZVT snubber assisted auxiliary switch torna-o competitivo em relação ao conversor ZVT PWM com fonte auxiliar de tensão constante (true PWM ZVS pole). Abstract in english This paper proposes an improved design to calculate the snubber auxiliary elements of ZVT DC-DC PWM converters with snubber assisted auxiliary switch. The proposed improved design guidelines are based on the reduction of the conduction losses through the auxiliary circuit. It is accomplished by the unique location of the turn-off snubber capacitor, which is shared by both active switches. By means of this improved design guidelines the converter efficiency can be increase (more) d. An efficiency comparative analysis is carried out and the experimental results, obtained from 1 kW, 100 kHz laboratory prototypes, show a relevant improvement in converter efficiency compared to the original converter design. In addition, experimental results also confirm that with the improved design the ZVT PWM converters with snubber assisted auxiliary switch can be competitive with ZVT PWM converters with constant auxiliary voltage source (True PWM ZVS pole).

Russi, J.; Martins, M. L.; Gründling, H. A.; Pinheiro, H.; Pinheiro, J. R.; Hey, H. L.

2005-03-01

231

An imroved design for ZVT DC-DC PWM converters with snubber assisted auxiliary switch  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes an improved design to calculate the snubber auxiliary elements of ZVT DC-DC PWM converters with snubber assisted auxiliary switch. The proposed improved design guidelines are based on the reduction of the conduction losses through the auxiliary circuit. It is accomplished by the unique location of the turn-off snubber capacitor, which is shared by both active switches. By means of this improved design guidelines the converter efficiency can be increased. An efficiency comparative analysis is carried out and the experimental results, obtained from 1 kW, 100 kHz laboratory prototypes, show a relevant improvement in converter efficiency compared to the original converter design. In addition, experimental results also confirm that with the improved design the ZVT PWM converters with snubber assisted auxiliary switch can be competitive with ZVT PWM converters with constant auxiliary voltage source (True PWM ZVS pole).Este artigo propõe uma metodologia de projeto aprimorada para determinação dos componentes auxiliares para o conversor ZVT CC-CC PWM snubber assisted auxiliary switch. O procedimento de projeto proposto é baseado na redução das perdas de condução no circuito auxiliar. Isto é somente possível devido à localização do capacitor snubber de bloqueio, o qual é compartilhado por ambas as chaves ativas. Através do procedimento de projeto proposto o rendimento do conversor pode ser aumentado. Uma análise comparativa do rendimento é apresentada e os resultados experimentais, obtidos de protótipos de laboratório de 1 kW, 100 kHz, mostram uma melhoria relevante em relação ao rendimento apresentado pelo projeto original. Além disso, os resultados experimentais também confirmam que o projeto proposto para o conversor ZVT snubber assisted auxiliary switch torna-o competitivo em relação ao conversor ZVT PWM com fonte auxiliar de tensão constante (true PWM ZVS pole).

J. Russi; M. L. Martins; H. A. Gründling; H. Pinheiro; J. R. Pinheiro; H. L. Hey

2005-01-01

232

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∘ .

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

2008-01-01

233

Basic circuits to design switched-based DC-DC converters  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish 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 aumenta (more) ndo 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 Abstract in english The purpose of this paper is twofold. On one hand, basics on switched circuits for designing a DC-DC converter are presented and, on the other hand, power electronics definitions associated with simple electrical networks are mentioned. In the analysis of these networks, it is necessary to take into account not only converters' non-idealities but also how to minimize power losses. Since power losses may be minimized by increasing the clock frequency of switched-based conv (more) erters, experimental results of basic clock generators are presented. These generators were implemented with low-cost components

Sandoval-Ibarra, F; Mercado-Moreno, J.R; Urióstegui-Vázquez, L.H

2007-12-01

234

Fast response double series resonant high-voltage DC-DC converter  

International Nuclear Information System (INIS)

In this paper, a novel double series resonant high-voltage dc-dc converter with dual-mode pulse frequency modulation (PFM) control scheme is proposed. The proposed topology consists of two series resonant tanks and hence two resonant currents flow in each switching period. Moreover, it consists of two high-voltage transformer with the leakage inductances are absorbed as resonant inductor in the series resonant tanks. The secondary output of both transformers are rectified and mixed before supplying to load. In the resonant mode operation, the series resonant tanks are energized alternately by controlling two Insulated Gate Bipolar Transistor (IGBT) switches with pulse frequency modulation (PFM). This topology operates in discontinuous conduction mode (DCM) with all IGBT switches operating in zero current switching (ZCS) condition and hence no switching loss occurs. To achieve fast rise in output voltage, a dual-mode PFM control during start-up of the converter is proposed. In this operation, the inverter is started at a high switching frequency and as the output voltage reaches 90% of the target value, the switching frequency is reduced to a value which corresponds to the target output voltage. This can effectively reduce the rise time of the output voltage and prevent overshoot. Experimental results collected from a 100-W laboratory prototype are presented to verify the effectiveness of the proposed system.

2012-01-01

235

A magnetic thin film inductor and its application to a MHz switching dc-dc converter  

Energy Technology Data Exchange (ETDEWEB)

The authors propose a novel structured magnetic thin film inductor using rotation magnetization only. The thin film inductor has a sandwich structure, which consists of a double-rectangular spiral coil between top and bottom CoZrNb amorphous thin films. The sputtered CoZrNb amorphous magnetic thin films have uniaxial magnetic anisotropy induced by direct current field annealing. The easy magnetization axis is directed to the main axis of the rectangular spiral coil. Hence, only the rotation magnetization process dominates in this device. The typical specifications are as follows: 3.5 x 5.5 mm in size, inductance of 1 [mu]H constant up to 10 MHZ, and a quality factor of 10 at 10 MHz. A MHz switching chopper dc-dc converter has been developed by using this thin film inductor, bare-chip semiconductor devices (a power MOSFET and a Schottky barrier diode), and a multilayer ceramic capacitor. This converter with a 0.1 cc volume has an output power over 1 W at 5 MHz switching, and the power density exceeds 10 W/cc (160 W/in.[sup 3]).

Sato, Toshiro; Tomita, Hiroshi; Sawabe, Atsuhito; Inoue, Tetsuo; Mizoguchi, Tetsuhiko; Sahashi, Masashi (Toshiba Corp., Kawasaki (Japan))

1994-03-01

236

Fast response double series resonant high-voltage DC-DC converter  

Science.gov (United States)

In this paper, a novel double series resonant high-voltage dc-dc converter with dual-mode pulse frequency modulation (PFM) control scheme is proposed. The proposed topology consists of two series resonant tanks and hence two resonant currents flow in each switching period. Moreover, it consists of two high-voltage transformer with the leakage inductances are absorbed as resonant inductor in the series resonant tanks. The secondary output of both transformers are rectified and mixed before supplying to load. In the resonant mode operation, the series resonant tanks are energized alternately by controlling two Insulated Gate Bipolar Transistor (IGBT) switches with pulse frequency modulation (PFM). This topology operates in discontinuous conduction mode (DCM) with all IGBT switches operating in zero current switching (ZCS) condition and hence no switching loss occurs. To achieve fast rise in output voltage, a dual-mode PFM control during start-up of the converter is proposed. In this operation, the inverter is started at a high switching frequency and as the output voltage reaches 90% of the target value, the switching frequency is reduced to a value which corresponds to the target output voltage. This can effectively reduce the rise time of the output voltage and prevent overshoot. Experimental results collected from a 100-W laboratory prototype are presented to verify the effectiveness of the proposed system.

Lee, S. S.; Iqbal, S.; Kamarol, M.

2012-10-01

237

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

CERN Multimedia

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

238

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.

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

2013-01-01

239

Pulse Current Regenerative Resonant Snubber-Assisted Two-Switch Flyback Type ZVS PWM DC-DC Converter  

Science.gov (United States)

In this paper, a two-switch high frequency flyback transformer type zero voltage soft switching PWM DC-DC converter using IGBTs is proposed. Effective applications for this power converter can be found in auxiliary power supplies of rolling stock transportation and electric vehicles. This power converter is basically composed of two active power switches and a flyback high frequency transformer. In addition to these, two passive lossless snubbers with power regeneration loops for energy recovery, consisting of a three winding auxiliary high frequency transformer, auxiliary capacitors and diodes are introduced to achieve zero voltage soft switching from light to full load conditions. Furthermore, this power converter has some advantages such as low cost circuit configuration, simple control scheme and high efficiency. Its operating principle is described and to determine circuit parameters, some practical design considerations are discussed. The effectiveness of the proposed power converter is evaluated and compared with the hard switching PWM DC-DC converter from an experimental point of view and the comparative electromagnetic conduction and radiation noise characteristics of both DC-DC power converter circuits are also depicted.

Inaba, Claudio Y.; Konishi, Yoshihiro; Nakaoka, Mutsuo

240

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

 
 
 
 
241

An Interleaved Reduced-Component-Count Multivoltage Bus DC/DC Converter for Fuel Cell Powered Electric Vehicle Applications  

Energy Technology Data Exchange (ETDEWEB)

An interleaved reduced-component-count dc/dc converter is proposed for power management in fuel cell powered vehicles with a multivoltage electric net. The converter is based on a simplified topology and can handle more power with less ripple current, therefore reducing the capacitor requirements, making it more suited for fuel cell powered vehicles in the near future. A prototype rated at 4.3 kW was built and tested to verify the proposed topology.

Tang, Lixin [ORNL; Su, Gui-Jia [ORNL

2008-01-01

242

A Low-Power Asynchronous Step-Down DC-DC Converter for Implantable Devices.  

UK PubMed Central (United Kingdom)

In this paper, we present a fully integrated asynchronous step-down switched capacitor dc-dc conversion structure suitable for supporting ultra-low-power circuits commonly found in biomedical implants. The proposed converter uses a fully digital asynchronous state machine as the heart of the control circuitry to generate the drive signals. To minimize the switching losses, the asynchronous controller scales the switching frequency of the drive signals according to the loading conditions. It also turns on additional parallel switches when needed and has a backup synchronous drive mode. This circuit regulates load voltages from 300 mV to 1.1 V derived from a 1.2-V input voltage. A total of 350 pF on-chip capacitance was implemented to support a maximum of 230-? W load power, while providing efficiency up to 80%. The circuit validating the proposed concepts was fabricated in 0.13- ?m complementary metal-oxide semiconductor technology. Experimental test results confirm the expected functionality and performance of the proposed circuit.

Al-Terkawi Hasib O; Sawan M; Savaria Y

2011-06-01

243

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

244

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

245

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

246

Performance and scalability of isolated DC-DC converter topologies in low voltage, high current applications  

Energy Technology Data Exchange (ETDEWEB)

Fuel cells are a promising alternative for clean and efficient energy production. A fuel cell is probably the most demanding of all distributed generation power sources. It resembles a solar cell in many ways, but sets strict limits to current ripple, common mode voltages and load variations. The typically low output voltage from the fuel cell stack needs to be boosted to a higher voltage level for grid interfacing. Due to the high electrical efficiency of the fuel cell, there is a need for high efficiency power converters, and in the case of low voltage, high current and galvanic isolation, the implementation of such converters is not a trivial task. This thesis presents galvanically isolated DC-DC converter topologies that have favorable characteristics for fuel cell usage and reviews the topologies from the viewpoint of electrical efficiency and cost efficiency. The focus is on evaluating the design issues when considering a single converter module having large current stresses. The dominating loss mechanism in low voltage, high current applications is conduction losses. In the case of MOSFETs, the conduction losses can be efficiently reduced by paralleling, but in the case of diodes, the effectiveness of paralleling depends strongly on the semiconductor material, diode parameters and output configuration. The transformer winding losses can be a major source of losses if the windings are not optimized according to the topology and the operating conditions. Transformer prototyping can be expensive and time consuming, and thus it is preferable to utilize various calculation methods during the design process in order to evaluate the performance of the transformer. This thesis reviews calculation methods for solid wire, litz wire and copper foil winding losses, and in order to evaluate the applicability of the methods, the calculations are compared against measurements and FEM simulations. By selecting a proper calculation method for each winding type, the winding losses can be predicted quite accurately before actually constructing the transformer. The transformer leakage inductance, the amount of which can also be calculated with reasonable accuracy, has a significant impact on the semiconductor switching losses. Therefore, the leakage inductance effects should also be taken into account when considering the overall efficiency of the converter. It is demonstrated in this thesis that although there are some distinctive differences in the loss distributions between the converter topologies, the differences in the overall efficiency can remain within a range of a few percentage points. However, the optimization effort required in order to achieve the high efficiencies is quite different in each topology. In the presence of practical constraints such as manufacturing complexity or cost, the question of topology selection can become crucial. (orig.)

Vaisanen, V.

2012-07-01

247

The development of 48 V/200 A, 100 Khz soft-switching DC-DC converter unit  

Energy Technology Data Exchange (ETDEWEB)

This paper is to describe how to apply the Phase-shifted Full Bridge(PSFB) 100 Khz high frequency soft-switching PWM method to 48 V, 200 A DC-DC converter. The soft-switching is achieved from light load to full load by using phase-shifted zero voltage switching method with additional capacitors besides the MOSFET`s of the right leg even though the leakage inductance of high frequency transformer is designed small. This method can reduce the switching losses, EMI problems, and increase the effective duty-Also, this paper includes the simulation, analysis, and experiment results of the DC-DC converter unit. (author). 4 refs.

Kye, M.H.; Joe, K.Y; Kim, E.S. [Korea Electrotechnology Research Institute, Changwon (Korea, Republic of); Juong, S.W. [Soo-young Electric Co.Ltd (Korea, Republic of); Kim, S.C.; Kuen, S.K. [Kyung-nam University, Masan (Korea, Republic of)

1995-12-01

248

Integrated modeling and control of a PEM fuel cell power system with a PWM DC/DC converter  

Energy Technology Data Exchange (ETDEWEB)

A fuel cell powered system is regarded as a high current and low voltage source. To boost the output voltage of a fuel cell, a DC/DC converter is employed. Since these two systems show different dynamics, they need to be coordinated to meet the demand of a load. This paper proposes models for the two systems with associated controls, which take into account a PEM fuel cell stack with air supply and thermal systems, and a PWM DC/DC converter. The integrated simulation facilitates optimization of the power control strategy, and analyses of interrelated effects between the electric load and the temperature of cell components. In addition, the results show that the proposed power control can coordinate the two sources with improved dynamics and efficiency at a given dynamic load. (author)

Choe, Song-Yul; Ahn, Jong-Woo [Mechanical Engineering Department, Auburn University, Auburn, AL 36848 (United States); Lee, Jung-Gi [Electrical Engineering Department, Pohang University of Science and Technology, Pohang (Korea); Baek, Soo-Hyun [Electrical Engineering Department, Dong-guk University, Seoul (Korea)

2007-02-10

249

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 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 bus voltage feedback using anti-windup PI back calculation control method. This outer loop would generate a reference current for the inner loop that implemented hysteresis control. The inner control loop compared that reference curent with the source current obtained from the current sensor. Simulation and experiment results showed that bus voltage was well-regulated under the load changes of 1% ripple voltage

Muh. Zakiyullah Romdlony; Amin Amin

2012-01-01

250

Analysis and modeling of a two-input DC/DC converter with two controlled variables and four switched networks  

Energy Technology Data Exchange (ETDEWEB)

Recently, a two-input tri-state DC/DC converter was presented capable of performing solar array peak-power tracking, battery power conditioning, and output voltage regulation all within the same converter structure. At light loads and during periods of low insolation, converter operation will naturally evolve through four linear switched networks. In this paper, the small-signal stability of the tri-state converter is analyzed and a large-signal averaged model is derived capable of predicting the dynamic behavior during and following transitions to and from this fourth state.

Rodriguez, F.D.; Imes, W.G. [Lockheed Martin Missiles and Space, Sunnyvale, CA (United States). Space Systems Div.

1996-12-31

251

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

2012-01-01

252

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,

253

An Improved Full-Bridge Zero-Voltage-Transition PWM DC-DC Converter with Zero-Voltage/Zero-Current Switching of the Auxiliary Switches  

Energy Technology Data Exchange (ETDEWEB)

In this paper, an improved Zero-Voltage-Transition PWM DC/DC converter topology is proposed. The proposed ZVT PWM DC/DC converter has an advantage of zero-voltage and zero-current switching of the auxiliary switches. The ZVS and ZCS operations can be achieved by using the saturable inductor and auxiliary capacitor. The operation principles are explained in detail and the validity of the proposed circuit is verified by the simulation results. (author). refs., figs.

Lee, D.Y.; Lee, B.K.; Hyun, D.S. [Hanyang University (Korea, Republic of)

1997-04-01

254

Development of thin inductor for DC to DC converter; DC-DC converter yo usugata inductor no kaihatsu  

Energy Technology Data Exchange (ETDEWEB)

A thin inductor of low magnetic noise is developed, to decrease size and thickness of DC to DC converter, and to make itself compatible with other control devices. It decreases the drum-shaped, inductor-carrying on-board DC-DC converter both in thickness and volume at least to half. The converter, in spite of its compactness, has better electrical, exothermic and magnetic noise characteristics than the conventional one. The 4mm thick inductor is designed using a magnetic field analyzing software to have better superimposed direct current and magnetic noise characteristics than the conventional one. Fusible, insulated conductor wires having a square section are closely wound around the winding sections arranged at intervals of 1mm on a flat ferrite core using a fusible bonded coil, to attain a high conductance. A compact switching device is put in a space between the main switching device and emitter in the conventional circuit to withdraw, at a high speed, charges accumulated in the main switch, thereby controlling loss at the main switch to improve its efficiency and also controlling heat radiation. 7 refs., 10 figs.

Kaneko, T.; Iwata, K. [Nippon Steel Corp., Tokyo (Japan); Tanikawa, K. [Kansai Research Institute, Kyoto (Japan); Hirano, H.; Tanaka, N.; Hirose, C.; Yahagi, S.

1997-04-30

255

A NEW SOFT SWITCHING SCHEME FOR AN ISOLATED BIDIRECTIONAL FULL-BRIDGE DC-DC CONVERTER FED DRIVE SYSTEM  

Directory of Open Access Journals (Sweden)

Full Text Available This paper deals with reducing switching loss, reducing voltage and current stresses, and reducing conduction loss due to circulation current. An isolated bidirectional full-bridge dc–dc converter with high conversion ratio, high output power, and soft start-up capability is proposed. The use of a capacitor, a diode, and a flyback converter can clamp the voltage spike caused by the current difference between the currentfed inductor and leakage inductance of the isolation transformer, and can reduce the current flowing through the active switches at the current-fed side.

M.Sasikumar; T.Umaranjani

2012-01-01

256

Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter  

Energy Technology Data Exchange (ETDEWEB)

Solar ADEPT Project: CU-Boulder is developing advanced power conversion components that can be integrated into individual solar panels to improve energy yields. The solar energy that is absorbed and collected by a solar panel is converted into useable energy for the grid through an electronic component called an inverter. Many large, conventional solar energy systems use one, central inverter to convert energy. CU-Boulder is integrating smaller, microinverters into individual solar panels to improve the efficiency of energy collection. The University’s microinverters rely on electrical components that direct energy at high speeds and ensure that minimal energy is lost during the conversion process—improving the overall efficiency of the power conversion process. CU-Boulder is designing its power conversion devices for use on any type of solar panel.

None

2012-02-09

257

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.

S. Sriraman; M. A. Panneerselvam

2012-01-01

258

A three-phase soft-switched high-power-density dc/dc converter for high power applications  

Energy Technology Data Exchange (ETDEWEB)

In this paper three dc/dc converter topologies suitable for high-power-density high-power applications are presented. All three circuits operate in a soft-switched manner, making possible a reduction in device switching losses and an increase in switching frequency. The three-phase dual-bridge converter proposed is seen to have the most favorable characteristics. This converter consists of two three-phase inverter stages operating in a high-frequency six-step mode. In contrast to existing single-phase ac-link dc/dc converters, lower turn-off peak currents in the power devices and lower rms current ratings for both the input and output filter capacitors are obtained. This is in addition to smaller filter element values due to the higher-frequency content of the input and output waveforms. Furthermore, the use of a three phase symmetrical transformer instead of single-phase transformers and a better utilization of the available apparent power of the transformer (as a consequence of the controlled output inverter) significantly increase the power density attainable.

DeDoncker, R.W.A.A. (Power Controls Lab., General Electric Corporate R and D, Schenectady, NY (US)); Divan, D.M.; Kheraluwala, M.H. (Dept. of Electrical and Computer Engineering, Univ. of Wisconsin, Madison, WI (US))

1991-01-01

259

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

International Nuclear Information System (INIS)

Research highlights: ? Hybrid electric power system for a real surface tramway. ? Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. ? New control strategy for the energy management of the tramway. ? 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.

2011-01-01

260

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

Directory of Open Access Journals (Sweden)

Full Text Available 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.

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

2010-01-01

 
 
 
 
261

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; E.S. Ali

2013-01-01

262

Current-fed Step-up DC/DC Converter for Fuel Cell Applications with Active Overvoltage Clamping  

Science.gov (United States)

In order to use hydrogen fuel cells in domestic applications either as main power supply or backup source, their low DC output voltage has to be matched to the level and frequency of the utility grid AC voltage. Such power converter systems usually consist of a DC-DC converter and a DC-AC inverter. A double inductor step-up push-pull converter is investigated in this paper, presenting simulation and experimental results for passive and active overvoltage clamping. The prototype of the investigated converter is elaborated for 1200 W power to match the rated power of the proton exchange membrane (PEM) fuel cell located in hydrogen fuel cell research laboratory.

Andreiciks, Aleksandrs; Steiks, Ingars; Krievs, Oskars

2010-01-01

263

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

264

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 desc...

Török, Lajos; Munk-Nielsen, Stig

265

Study of a piezoelectric transformer-based DC/DC converter with a cooling system and current-doubler rectifier  

Science.gov (United States)

The objective of this study was to increase the output current and power in a piezoelectric transformer (PT)-based DC/DC converter by using a cooling system. It is known that the output current of a PT is limited by temperature build-up because of losses, especially when driving at high vibration velocity. Although connecting different inductive circuits at the PT secondary terminal can increase the output current, the root cause of the temperature build-up problem has not yet been solved. This paper presents a study of a PT with cooling system in a DC/DC converter with a commonly used full-bridge rectifier and current-doubler rectifier. The advantages and disadvantages of the proposed technique were investigated. A theoretical-phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as heat generation increases the losses. In our design, the maximum output current capacity can increase by 100% when the temperature of operation of the PT is kept below 55?° C. The study comprises a theoretical part and experimental proof-of-concept demonstration of the proposed design method.

Su, Yu-Hao; Liu, Yuan-Ping; Vasic, Dejan; Costa, Francois; Wu, Wen-Jong; Lee, Chuih-Kung

2013-09-01

266

DESIGN AND CONSIDERATIONS OF A COMPENSATION LACE FOR THE CONVERTER- BOOSTER DC-DC CONTROLLED IN VOLTAGE MODE  

Directory of Open Access Journals (Sweden)

Full Text Available In this article we introduce the design of a compensation lace in a converter of the Booster type DC-DC which will allow maintaining the converter operation in steady state, working at a maximum power of 600 W in the charge. This design has the characteristic of operating in the continuous mode of current conduction (CCM) and being controlled in the voltage mode. In this type of systems for medium power the presence of the zero located to the right of the plane in s (RHP) makes almost impossible the control by voltage mode in CCM. Some considerations of design will be determined to overcome this effect in the system obtaining therefore a broader bandwidth of response frequency. The design of the converter-booster CD-CD was taken to implementation and simulation phases where satisfactory results were obtained.

David R. López Flores; Alejandro Lizárraga Lizárraga; José L. Durán Gómez

2005-01-01

267

Analysis and design of snubber circuits for high-power GTO DC-DC converters. [Gate Turn Off  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the analysis and the design of snubber circuits for high power DC-DC converters realized with Gate Turn Off (GTO) thyristors. These networks are fundamental for the safe operation of semiconductor devices but dissipate some energy. Means to minimize their losses are studied in this work. The snubber circuits described here are an evolution of the conventional C-snubber and L-snubber. The design of the snubbers is based upon circuits that permit the transfer of the trapped energy to the power source or to the load. Benefits, drawbacks and limits of each new proposed circuit are detailed and studied. Experimental results, obtained from a GTO laboratory prototype converter are reported.

Brambilla, A. (Politecnico di Milano (Italy). Dipt. di Elettronica ed Informazione); Dallago, E. (Univ. of Pavia (Italy). Dipt. di Ingegneria Elettrica)

1994-01-01

268

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

International Nuclear Information System (INIS)

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.

2010-01-01

269

Reduction of vehicle CO{sub 2} emission with application of DC/DC converter; Einsatz von DC/DC-Wandlern in Kraftfahrzeugen zur Reduzierung von CO{sub 2} Emissionen  

Energy Technology Data Exchange (ETDEWEB)

DC to DC converter in vehicles are more and more enabling technologies for innovative powernet architectures which are required by new approaches to reduce fuel consumption. Increasing fuel prices and legislative requirements concerning emission are demanding for a close realization on the existing powernet. Applications like Stop/Start which can be implemented into todays powernet solutions requiring slight modifications only contribute already to reduction of CO{sub 2} emissions. This article describes different powernet architectures, which provide significant saving potential, on the basis of DC/DC-converter without representing a convenience limitation to the passenger. (orig.)

Floettmann, B.; Weghaus, L.; Schoellmann, M. [Hella KGaA Hueck und Co., Lippstadt (Germany)

2007-07-01

270

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

271

Practical Evaluations of Improved Active Edge-Resonant ZCS-PWM Boost DC-DC Converter and Its Extended Circuit Topologies  

Science.gov (United States)

A practical ZCS-PWM active edge-resonant cell employing the parasitic oscillation-suppressed clamping diodes is presented in this letter. The improved active edge-resonant cell is quite effective for suppressing the surge voltages at the turn-off transitions of active power devices, thereby reduction of the voltage rating of the power devices and circuit components can be achieved. The practical effectiveness of the improved active edge-resonant cell is confirmed by the experiments on the newly-developed ZCS-PWM boost DC-DC converter, and furthermore its extended ZCS-PWM DC-DC converter topologies are originally proposed.

Mishima, Tomokazu; Miyake, Shuji; Nakaoka, Mutsuo

272

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; Dr. Swapnajit Pattnaik

2012-01-01

273

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

1990-01-01

274

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

275

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

276

Multiphase soft switched DC/DC converter and active control technique for fuel cell ripple current elimination  

Energy Technology Data Exchange (ETDEWEB)

DC/DC converter has a transformer having primary coils connected to an input side and secondary coils connected to an output side. Each primary coil connects a full-bridge circuit comprising two switches on two legs, the primary coil being connected between the switches on each leg, each full-bridge circuit being connected in parallel wherein each leg is disposed parallel to one another, and the secondary coils connected to a rectifying circuit. An outer loop control circuit that reduces ripple in a voltage reference has a first resistor connected in series with a second resistor connected in series with a first capacitor which are connected in parallel with a second capacitor. An inner loop control circuit that reduces ripple in a current reference has a third resistor connected in series with a fourth resistor connected in series with a third capacitor which are connected in parallel with a fourth capacitor.

Lai, Jih-Sheng (Blacksburg, VA); Liu, Changrong (Sunnyvale, CA); Ridenour, Amy (Salem, VA)

2009-04-14

277

High voltage dc-dc converter with dynamic voltage regulation and decoupling during load-generated arcs  

Energy Technology Data Exchange (ETDEWEB)

A high-power power supply produces a controllable, constant high voltage output under varying and arcing loads. The power supply includes a voltage regulator, an inductor, an inverter for producing a high frequency square wave current of alternating polarity, an improved inverter voltage clamping circuit, a step up transformer, an output rectifier for producing a dc voltage at the output of each module, and a current sensor for sensing output current. The power supply also provides dynamic response to varying loads by controlling the voltage regulator duty cycle and circuitry is provided for sensing incipient arc currents at the output of the power supply to simultaneously decouple the power supply circuitry from the arcing load. The power supply includes a plurality of discrete switching type dc--dc converter modules.

Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)

1995-01-01

278

Improving the Response of a DC/DC Converter by Providing a New Structure for Embedded Schottky Diode  

Directory of Open Access Journals (Sweden)

Full Text Available Paper In this paper, a new schottky diode with high speed switching is presented. Reverse recovery current and reverse recovery time are two parameters to determine the switching speed of power diodes. If a method could control the depletion of majority carriers in cut off time, it can enhance the switching speed. In this work, some islands, with non-similar type to bulk, are implemented in the bulk of the diode. These islands can gather and recombine the abandon majority carriers. So, the reverse recovery current can be limit by this way. To test this structure a simple fast schottky diode is applied in a DC/DC converter. The simulations are done in Silvaco software.

Hamed Sepahvand,; Soghra Raisi,

2013-01-01

279

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 conver...

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

280

A Fully-Integrated Switched-Capacitor Step-Down DC-DC Converter With Digital Capacitance Modulation in 45 nm CMOS  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Implementing efficient and cost-effective power regulation schemes for battery-powered mixed-signal SoCs is a key focus in integrated circuit design. This paper presents a fully-integrated switched-capacitor DC-DC converter in 45 nm digital CMOS technology. The proposed implementation uses digital c...

Ramadass, Yogesh Kumar; Fayed, Ayman A.; Chandrakasan, Anantha P.

 
 
 
 
281

Transformer parasitic inductor component-assisted soft-commutation DC-DC converter with rectifier side active power switching control scheme  

Energy Technology Data Exchange (ETDEWEB)

This paper presents a new prototype of phase-shifted ZVS-PWM DC-DC converter with choke input type smoothing filter which has two active power switches in rectifier side. The wide ZVS area at primary side and ZCS area at secondary side by using parasitic inductor component of high-frequency transformer can be achieved by this converter. Its operation principle and feature are explained and compared with those of the previously-developed ZVS-PWM DC-DC converter. The steady-state operating characteristics of the proposed converter topology are illustrated and discussed on the basis of the simulation results and experimental ones. Finally, another converter with capacitor input type smoothing filter which operates under a principle of this converter is explained here in. (orig.)

Morimoto, Takeshi; Saitoh, Kouhei; Nakamura, Mantaro; Nakaoka, Matsuo [Dept. of Electrical and Electronics Engineering, Yamaguchi Univ., Yamaguchi (Japan)

2000-07-01

282

Comparative Study on  Paralleled vs. Scaled Dc-dc Converters  in High Voltage Gain Applications  

DEFF Research Database (Denmark)

Today power converters are present in many commercial, medical and industrial applications. A lot of them are high power and high current applications. In order to increase power handling capability several transistors or diodes are paralleled often. However such paralleling may lead to converter's performance degradation or switches quick failure. A parallel modular converter built of many paralleled modules may be an interesting alternative, while a modular converter provides well known advantages like scalability, improved reliability and lower cost. This paper investigates possibility of improving an efficiency by intelligent usage of a modular boost converter in a high voltage gain application.

Klimczak, Pawel; Munk-Nielsen, Stig

2008-01-01

283

A New Soft Switching Current fed DC-DC Converter for Medium Power Applications  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper a new zero voltage switching current fed half bridge converter with an auxiliary circuit is proposed. The auxiliary circuit not only absorbs the voltage surge across switches at turn off instance, but also provides zero voltage switching condition for all converter switches. Therefore in this converter the efficiency is higher than hard switching counterpart and also main switches voltage stresses decrease. Since the switches in auxiliary circuit operate under soft switching conditions, these switches don’t apply additional losses to proposed converter. Implementation of control circuit is very simple since the converter is PWM controlled and the auxiliary switches turn on are complementary with respect to main switches. In this paper the proposed converter operating modes are analyzed and simulation results are presented. To verify the converter operation a 100W laboratory prototype operating at 100kHz is implemented and the experimental results are presented.

Majid Delshad

2008-01-01

284

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

285

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

286

Isolated DC-DC UPS Based in a Fly back Converter Analysis and Design  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the analysis, design andsimulation from a simple DC-UPS converter with integratedback-up and automatic transition. This converter makesautomatic transition between the main AC and the battery when afailure occurs, and it delivers uninterrupted DC power to the loadthrough two independent power sources of commercial inputpower and battery power. The converter has the followingcharacteristics: automatic transition between the main and thebattery, no additional control to detect failure in the main, singlestructure, galvanic isolation, multi output voltages capability andonly one switch control for two operation modes normal andback-up. The analysis, design, simulation and experimentalresults for this converter are presented.

Prof. Raju Bhabhor; Jitendrakumar A. Jadav; Rinal K. Ahir

2013-01-01

287

Gate Driver Circuit of Power Electronic Switches with Reduced Number of Isolated DC/DC Converter for a Switched Reluctance Motor  

International Nuclear Information System (INIS)

This paper presents a gate driver circuit for the switching devices used in the asymmetrical converter for a switched reluctance machine with reduced number of isolated dc/dc converters. Isolation required in the gate driver circuit of switching devices is indispensable. For the purpose of isolation different arrangements may be used such as pulse transformers. The dc/dc converter for isolation and powering the gate drive circuits is suitable, cheaper in cost and simple to implement. It is also significant that required number of isolation converters is much less than the switches used in converter. In addition, a simple logic circuit has been presented for producing the gate signals at correct phase sequence which is compared with the gated signals directly obtained from the encoder of an existing machine. (author)

2013-01-01

288

Soft Switching Forward DC/DC Converter Using Non-Dissipative Snubber  

Energy Technology Data Exchange (ETDEWEB)

To achieve high efficiency in high power and high frequency applications, use of non-dissipative snubbers is very important. In this paper, an improved soft switching forward converter is proposed. The proposed converter is constructed by using non-dissipate snubbers in parallel with the main switch and output diode of the conventional forward converter. Due to use of the non-dissipative snubbers in the primary and secondary, the proposed converter achieves zero-voltage and zero-current achieves zero-voltage and zero-current switching for all switching devices without switching losses and output diode recovery losses. The complete operating principles, theoretical analysis, and simulation and experimental results will be presented. (author). refs., figs.

Kim, E.S.; Joe, K.Y.; Byun, Y.B.; Kim, T.J.; Choi, H.Y. [Korea Electrotechnology Research Institute (Korea, Republic of); Kim, Y.H.; Youn, B.D. [Chung Ang University (Korea, Republic of)

1997-04-01

289

Experimental study of a bidirectional DC-DC converter for the DC link voltage control and the regenerative braking in PM motor drives devoted to electrical vehicles  

Energy Technology Data Exchange (ETDEWEB)

The use of a bidirectional DC-DC converter operating in the DC link of CRPWM-inverter-fed motor drives devoted to electric vehicles (EVs) application allows a suitable control of both motoring and regenerative braking operations, and it can contribute to a significant increase of the motor drive overall efficiency. This paper deals with the experimental study of a bidirectional DC-DC converter prototype which has been designed for application in small-size EVs propelled by axial-flux PM motor drives. The paper discusses the converter modes of operation and reports the experimental results taken from a converter prototype which has been constructed using an IGBTs power module rated 600 V, 50 A. 2 refs.

Caricchi, F.; Crescimbini, F.; Noia, G.; Pirolo, D. [Rome Univ. (Italy). Dept. of Electrical Engineering

1994-12-31

290

DC-DC converters in distributed photovoltaic electricity system. Analysis, control and design  

Energy Technology Data Exchange (ETDEWEB)

This thesis presents a comprehensive review on switched-mode converters in terms of dynamic behavior and practical limitations that arise from the fundamental properties of the electrical sources and loads, control engineering principles and topological properties of the converters. The main focus is on analyzing the behavior of a single converter used to interface a photovoltaic generator into a high-voltage dc link. The main objective is to introduce interfacing principles with numerous examples and a thorough discussion. The interfacing of photovoltaic generators by means of switched-mode converters has proven to be problematic according to numerous scientific publications indicating operational disadvantages and anomalies. The output characteristics of the photovoltaic generator, which are bound to varying environmental conditions, introduce design challenges. It has been recognized recently that the photovoltaic generator does not contain similar electrical behavior as conventional electrical sources, most notably due to its limited-power characteristics, yielding two distinctive operating regions. Yet, the constraints arising from the properties of the source have not been completely recognized, although the effect of these constraints can be seen from the published research results. When switched-mode converters are used to adapt individual photovoltaic modules into larger system by connecting converters in series or in parallel, severe operational limitations are observed. On the other hand, if the photovoltaic generator is substituted with a source that does not contain similar characteristics, observations may lead to misconclusions as the effect of the photovoltaic generator is not properly modeled. Therefore, claims that are not valid for actual applications with photovoltaic generators may be presented and widely accepted. This thesis presents methods to perform proper analysis of switched-mode converters implemented in distributed photovoltaic applications, by continuing previous work around the subject. The dynamic models for series-connected and parallelconnected systems of interfacing converters are given, explaining the observed operational anomalies. Additionally, it is shown by a thorough review that the parallel configuration does not contain the claimed disadvantageous properties and actually provides better performance. A patented converter topology designed for the parallel configuration is presented with comprehensive analysis and practical validation. Finally, the problematics of photovoltaic interfacing is summarized under the interfacing constraints, which give guidelines for design and analysis of interfacing converters. (orig.)

Huusari, J.

2012-10-15

291

Transformer less DcDc Converter with high Step up Voltage gain Method  

Directory of Open Access Journals (Sweden)

Full Text Available 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 power stages; their operation is integrated. The simplicity and robustness of the solution, the possibility of getting higher voltage ratios than cascading boost converters, without using transformers with all theirproblems, and the good overall efficiency are the benefits of the proposed converter

K.Raja Gopal1 , B. Gavaskar Reddy2 , M.Venkateswara Reddy3 , S.Srikanth4 , K.Suresh5

2011-01-01

292

Multivariable Modeling and Decentralized Robust Linear Controllers for Current-Sharing DC/DC Converters  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, the multivariable approach is utilized to obtain linear models of current-sharing switching converters. These multivariable linear models are suited for frequency framework of various linear control design techniques. Frequency domain setup is proposed for the robust linear design and all of its elements are defined in order to obtain simple decentralized robust PI/PID type controllers by reduction. The feasibility of the approach is verified for robustness and performance in a three parallel boost converters case study.

Aleksandar Ž. Raki?; Trajko B. Petrovi?

2009-01-01

293

High-Efficiency Self-Adjusting Switched Capacitor DC-DC Converter with Binary Resolution  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Switched-Capacitor Converters (SCC) suffer from a fundamental power loss deficiency which make their use in some applications prohibitive. The power loss is due to the inherent energy dissipation when SCC operate between or outside their output target voltages. This drawback was alleviated in this w...

Kushnerov, Alexander

294

An Efficiency-Optimized Isolated Bidirectional DC-DC Converter with Extended Power Range for Energy Storage Systems in Microgrids  

Directory of Open Access Journals (Sweden)

Full Text Available This paper proposes a novel extended-single-phase shift (ESPS) control strategy of isolated bidirectional full-bridge DC-DC converters (IBDCs) which are a promising alternative as a power electronic interface in microgrids with an additional function of galvanic isolation. Based on the mathematical models of ESPS control under steady-state conditions, detailed theoretical and experimental analyses of IBDC under ESPS control are presented. Compared with conventional single-phase-shift (CSPS) control, ESPS control can greatly improve the efficiency of IBDCs in microgrids through decreasing current stress and backflow power considerably over a wide input and output voltage range under light and medium loads. In addition, ESPS control only needs to adjust one single phase-shift angel to control transmission power, thus it retains implementation simplicity in comparison with dual-phase-shift (DPS) control for microgrid applications. Furthermore, an efficiency-optimized modulation scheme based on ESPS and CSPS control is developed in the whole power range of IBDC for power distribution in microgrids. A 10 kW IBDC prototype is constructed and the experimental results validate the effectiveness of the proposed control strategy, showing that the proposed strategy can enhance the overall efficiency up to 30%.

Xiaolong Shi; Jiuchun Jiang; Xintao Guo

2012-01-01

295

Calculation of Spectral Peaks in a Chaotic Dc--Dc Converter  

UK PubMed Central (United Kingdom)

A simple mapping is derived which describes the behaviour of a peak current-modecontrolled boost converter operating chaotically. The invariant density of this mapping iscalculated iteratively, and from this the power spectral density of the input current at theclock frequency and its harmonics is deduced. The calculation is presented, along withexperimental verification, and the possibility of EMC improvement by chaos is discussed.1. IntroductionIn a previous publication [1] we presented the idea that chaos, a naturally occurring phenomenonin switch-mode power supplies, might be used to improve their electromagnetic compatibility. Weillustrated this proposal with some measurements. In the present paper we show how to calculatethe power spectral density (PSD) at the clock frequency and its harmonics, of the input current of acurrent-mode controlled boost converter operating chaotically. This work builds mainly on [2]--[4], inwhich we derived an exact two-dimensional mapping...

J. H. B. Deane; P. Ashwin; D. C. Hamill; D. J. Jefferies; Guildford Gu Xh

296

Design and implementation of adaptive slope compensation in current mode DC-DC converter  

International Nuclear Information System (INIS)

To improve the compensation for the inherent instability in a current mode converter, the adaptive slope compensation, giving attention to the problems of the traditional compensation on compensation accuracy, loading capability and turning jitter, is presented. Based on the analysis of current loop, by detecting the input and output voltage, converting the adaptive slope compensation current, the compensation of the current loop is optimized successfully. It can not only improve the compensation accuracy but also eliminate the over compensation, the turning jitter and the poor loading capability in the reported slope compensation. A power supply chip with adaptive slope compensation has been fabricated in a 0.35 ?m CMOS process. The measurement results show that the chip starts up and operates steadily with the constant current limit under conditions of 5 V input voltage, from 10% to 100% duty cycle. (semiconductor integrated circuits)

2010-01-01

297

Calculation of Spectral Peaks in a Chaotic Dc-Dc Converter  

UK PubMed Central (United Kingdom)

A simple mapping is derived which describes the behaviour of a peak current-modecontrolled boost converter operating chaotically. The invariant density of this mapping iscalculated iteratively, and from this the power spectral density of the input current at theclock frequency and its harmonics is deduced. The calculation is presented, along withexperimental verification, and the possibility of EMC improvement by chaos is discussed.1. IntroductionIn a previous publication [1] we presented the idea that chaos, a naturally occurring phenomenonin switch-mode power supplies, might be used to improve their electromagnetic compatibility. Weillustrated this proposal with some measurements. In the present paper we show how to calculatethe power spectral density (PSD) at the clock frequency and its harmonics, of the input current of acurrent-mode controlled boost converter operating chaotically. This work builds mainly on [2]--[4], inwhich we derived an exact two-dimensional mapping...

J. H. B. Deane; P. Ashwin; D. C. Hamill; D. J. Jefferies; Guildford Gu Xh

298

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.

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

2012-01-01

299

A NEW SOFT-SWITCHING ACTIVE CLAMP SCHEME FOR FULL-BRIDGE ISOLATED CURRENT FED DC-DC CONVERTER FED DRIVES  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents on a new high power full bridge isolated current fed dc/dc Converter with an active clamp. A proposed current fed dc/dc converter with high efficiency and voltage boosting capability is designed for use in the interface between a low voltage fuel cell source and a high voltage dc bus for inverters.ZVS scheme in all active switches is achieved for using a soft switching scheme. The switching losses and the conduction losses are reduced and the performance of the drive system should be increased from the proposed model. The proposed converter system is controlled by SPWM Technique. The simulation results are carried out and presented.

M.Sasikumar; M.Geetha

2012-01-01

300

A New Low-Stress Buck-Boost Converter for  

UK PubMed Central (United Kingdom)

In converters for power-factor-correction (PFC),universal-input capability (ability to operate from any AC linevoltage, world-wide) comes with a heavy price in terms ofcomponent stresses and losses, size of components, andrestrictions on the output DC voltage. A new two-switchtopology is proposed to offer very significant performanceimprovements over the single-switch buck-boost converters(including flyback, SEPIC, and Cuk topologies) andconventional two-switch buck-boost cascaded converters. Theproposed converter has buck-boost conversion characteristic,switch conduction losses comparable to the boost converter, noinrush current problem, and potential for smaller inductor sizecompared to the boost converter.

Colorado Power

 
 
 
 
301

A variable step-down conversion ratio switched capacitor DC-DC converter for energy harvesting systems working in intermittent mode  

International Nuclear Information System (INIS)

Energy harvesting systems stimulate the development of power management for low power consumption applications. Improving the converter efficiency of power management circuits has become a significant issue in energy harvesting system design. This paper presents a variable step-down conversion ratio switched capacitor (SC) DC-DC converter to advance the converter efficiency of charge on the stored capacitor in a wireless monitoring system of orthopedic implants. The converter is designed to work at 1 MHz switching frequency and achieves 15 to 2 V conversion. Measurement results show that the converter efficiency can reach 42% including all circuit power consumption, which is much higher than previous work. (semiconductor integrated circuits)

1000-01-00

302

Tests on conducted electrical noise on a storage ring dc-dc converter cabinet  

International Nuclear Information System (INIS)

Electrical noise is produced by switching transients in the power supply converters which excite resonances formed by stray capacitance and cable inductance. This noise is present not only on the load cables, but also on ground cables of the magnet and of the converter cabinet. Since there will eventually be a large number of cabinets running at one time, tests were carried out to characterize the noise and to investigate possible techniques for reducing the levels. The tests were carried out on the test girder and converter cabinet set up in 412 area. There were four magnets installed on the girder -- two 0.5m quadrupoles, a 0.8m quadrupole, and a sextupole. These tests were carried out on one of the 0.5m quadrupoles. It should be noted that with this setup, the raw dc power was supplied at around 70V. In the final configuration, a 0.5m quad will be fed from a 40V raw supply. Consequently, the switching transients observed during the tests are likely to be higher than will occur in reality. Noise currents contain two main components: a low frequency component at around 50kHz, and a higher frequency component at around lMHz. It is the latter component which is of primary concern. Currents measured on the dc load cables typically were around one ampere, while currents into the building ground system were only a few tens of milliamps. Several methods were used to try reducing the noise currents, but only the addition of a series impedance was successful -- other methods either had no effect or increased the ground currents

1994-01-01

303

Tests on conducted electrical noise on a storage ring dc-dc converter cabinet  

Energy Technology Data Exchange (ETDEWEB)

Electrical noise is produced by switching transients in the power supply converters which excite resonances formed by stray capacitance and cable inductance. This noise is present not only on the load cables, but also on ground cables of the magnet and of the converter cabinet. Since there will eventually be a large number of cabinets running at one time, tests were carried out to characterize the noise and to investigate possible techniques for reducing the levels. The tests were carried out on the test girder and converter cabinet set up in 412 area. There were four magnets installed on the girder -- two 0.5m quadrupoles, a 0.8m quadrupole, and a sextupole. These tests were carried out on one of the 0.5m quadrupoles. It should be noted that with this setup, the raw dc power was supplied at around 70V. In the final configuration, a 0.5m quad will be fed from a 40V raw supply. Consequently, the switching transients observed during the tests are likely to be higher than will occur in reality. Noise currents contain two main components: a low frequency component at around 50kHz, and a higher frequency component at around lMHz. It is the latter component which is of primary concern. Currents measured on the dc load cables typically were around one ampere, while currents into the building ground system were only a few tens of milliamps. Several methods were used to try reducing the noise currents, but only the addition of a series impedance was successful -- other methods either had no effect or increased the ground currents.

Carwardine, J.J.

1994-02-22

304

Soft Switching Full-Bridge PWM DC/DC Converter Using Secondary Snubber  

Directory of Open Access Journals (Sweden)

Full Text Available A novel full-bridge PWM DC/DCconverter with controlled secondary side rectifier usingsecondary snubber is presented in this paper.Limitation of the circulating current as well as softswitching for all power switches of the inverter isachieved for full load range from no-load to shortcircuit by using controlled rectifier and snubber on thesecondary side. Phase shift PWM control strategy isused for the converter. The principle of operation isexplained and analyzed and the experimental resultson a 1kW, 50 kHz laboratory model of the converterare presented.

Jaroslav Dudrik; Vladimír Ruš?in; Marcel Bodor; Daniel Nistor Trip; Pavol Špánik

2009-01-01

305

A fast dynamic response dc-dc converter for high voltage applications  

International Nuclear Information System (INIS)

This paper present a fast dynamic response de-de converter for high voltage application such as medical use X-ray generator. In the proposed de-de converter a zero-current switching series resonant inverter is used to drive input terminals of voltage multiplier circuit. The zero-current switching series resonant inverter operates at fixed frequency and duly ratio. A control circuit is used at the lower arm of the inverter, to control the effective input voltage across the inverter. At the turn on the inverter is supplied with maximum effective input voltage, which results in quick rise-up of the output voltage. As the output voltage approaches to 80% of it target voltage, the effective input voltage is reduced to a value which corresponds to the target output voltage, as a result the rise rate of the output voltage becomes slow and overshoot is avoided. The effectiveness of the proposed control scheme has been confirmed experimentally with a laboratory scale- down prototype. (author)

2008-01-01

306

Experimental Discussion on a 6-kW, 2-kWh Battery Energy Storage System Using a Bidirectional Isolated DC/DC Converter  

Science.gov (United States)

This paper presents an experimental discussion on a 6-kW, full-bridge, zero-voltage switching bidirectional isolated dc/dc converter for a 53.2-V, 2-kWh Li-ion battery energy storage system. The combination of high-frequency switching devices, 600-V/200-A IGBTs and 100-V/500-A MOSFETs with a high-frequency transformer reduces the weight and physical size of the bidirectional isolated dc/dc converter. The dc voltage on the high-voltage side of the converter is controlled in a range of 300V to 355V as the battery voltage on the low-voltage side varies from 50V to 59V. Experimental verification of bidirectional power flow into (battery charging) or out of (battery discharging) the Li-ion battery bank is also presented. The maximal efficiency of the dc/dc converter is measured to be 98.1% during charging and 98.2% during discharging, excluding the gate drive loss and control circuit loss.

Abe, Takahiro; Tan, Nadia Mei Lin; Akagi, Hirofumi

307

Characterization of a fully resonant, 1-MHz, 25-watt, DC/DC converter fabricated in a rad-hard BiCMOS/high-voltage process  

International Nuclear Information System (INIS)

This paper presents the characterization of a DC/DC converter prototype when its power integrated circuit (PIC) chip is exposed to total dose, dose rate, neutron, and heavy ion environments. This fully resonant, 1-MHZ, 25-Watt, DC/DC converter is composed of a brassboard, populated with input/output filters, isolation transformers, output rectifier, capacitors, resistors, and PIC chip, integrating the primary-side control circuitry, secondary-side control circuitry, power switch, gate-drive circuitry, and voltage references. The brassboard is built using commercial off-the-shelf components; and the PIC chip is fabricated using AT and T's rad-hard, bipolar complementary metal-oxide semiconductor (BiCMOS)/high-voltage process. The intent of this paper is to demonstrate that the PIC chip is fabricated with a radiation-hardened process and to demonstrate that various analog, digital, and power functions can be effectively integrated

1995-01-01

308

Characterization of a fully resonant, 1-MHz, 25-watt, DC/DC converter fabricated in a rad-hard BiCMOS/high-voltage process  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the characterization of a DC/DC converter prototype when its power integrated circuit (PIC) chip is exposed to total dose, dose rate, neutron, and heavy ion environments. This fully resonant, 1-MHZ, 25-Watt, DC/DC converter is composed of a brassboard, populated with input/output filters, isolation transformers, output rectifier, capacitors, resistors, and PIC chip, integrating the primary-side control circuitry, secondary-side control circuitry, power switch, gate-drive circuitry, and voltage references. The brassboard is built using commercial off-the-shelf components; and the PIC chip is fabricated using AT and T`s rad-hard, bipolar complementary metal-oxide semiconductor (BiCMOS)/high-voltage process. The intent of this paper is to demonstrate that the PIC chip is fabricated with a radiation-hardened process and to demonstrate that various analog, digital, and power functions can be effectively integrated.

Titus, J.L.; Gehlhausen, M.A. [Naval Surface Warfare Center, Crane, IN (United States); Desko, J.C. Jr. [AT and T Bell Labs., Allentown, PA (United States); Nguyen, T.T.; Roberts, D.J. [AT and T Bell Labs., Whippany, NJ (United States); Shibib, M.A.; Hollenbach, K.E. [AT and T Bell Labs., Reading, PA (United States)

1995-12-01

309

A Novel Two Switch Non-inverting Buck-Boost Converter based Maximum Power Point Tracking System  

Directory of Open Access Journals (Sweden)

Full Text Available A solar module can’t transfer maximum power to the load itself due to impedance mismatch. A maximum power point tracking (MPPT) system could be employed to have the maximum power.  A new MPPT system has been developed using Buck-Boost type DC-DC converter. The system is highly efficient and robust. PIC16F73 microcontroller has been used to control the DC-DC converter output. PV module output power is measured using microcontroller. The output power is compared with the previous module output power and the duty cycle of the converter is adjusted continuously to track MPP.  This process repeats until the output power reaches near to the maximum power point.In this paper, a maximum power point tracking (MPPT) system is developed using  two-switch non-inverting buck-boost converter. Perturb and observe (P & O) MPPT algorithm is used to transfer maximum power from the PV panel which is executed using a microcontroller.

Khandker Tawfique Ahmed; Mithun Datta; Nur Mohammad

2013-01-01

310

Zero-Voltage Soft-Switched PWM High-Frequency AC-Link DC-DC Converters Incorporating Saturable Reactor-Assisted Capacitive Lossless Snubber Topology for Distributed Power Supply Systems.  

Science.gov (United States)

A new constant frequency soft switching phase shifted mode Pulse Width Modulated (PWM) DC-DC power converter topology suitable for high power applications, which incorporates two phase half bridge high frequency inverter and saturable reactor in series wi...

S. Nagai T. Yamamoto M. Nakaoka S. Hamada

1991-01-01

311

Research on a Novel Soft-Switching Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Based on classical zero voltage transition buck pwm converter, an ideal buck converter with pwm-controlled soft-switching circuit is proposed. The proposed auxiliary circuit allows the main switch to operate with zero-voltage switching. Besides, all of the semiconductor devices operate under soft-switching conditions. Thus, losses were reduced. It was analyzed in detail to demonstrate the operating principle of the novel circuit. Finally, simulation results are given analysis and the simulation results are provided to verify the performance of the proposed buck Converter.

Yuanbin Li; Peng Ge; Ben Niu

2013-01-01

312

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

313

A three-phase current-fed dc/dc converter with a three-leg high frequency transformer for fuel cells  

Energy Technology Data Exchange (ETDEWEB)

In this paper, a three-phase current-fed dc/dc converter with an active clamp is introduced, and a new three-phase three-leg high frequency transformer is proposed for the converter. The three-phase dc/dc converter transfers power through transformer leakage inductances in the discontinuous current mode; a single common active clamp branch is employed for zero-voltage switching (ZVS) in all active switches. Further, the converter's three-phase power configuration increases power transfer, and it reduces the rms current per phase, thus reduces conduction losses. Moreover, a delta-delta connection on the three-phase transformer provides parallel current paths and reduces conduction losses in the transformer windings. A three-phase transformer can be constructed by connecting three discrete single-phase transformers, but this process results in a higher volume and higher material costs. Therefore, a new three-phase three-leg high frequency transformer is designed with three discrete cores integrated into a single transformer core. The proposed transformer is analyzed according to the several operating modes of the converter, and its design rules are determined. Experimental results are obtained on a 500-W prototype unit; the design is fully verified and analyzed. (author)

Cha, Hanju [Department of Electrical Engineering, Chungnam National University, 220 Gung-dong Yuseong-gu, Daejeon 305-764 (Korea); Choi, Jungwan [National Fusion Research Institute, Daejeon (Korea); Enjeti, Prasad [Texas A and M University, College Station, TX 77843-3128 (United States)

2008-07-15

314

Series Resonant ZCS-PFM DC-DC Power Converter with High-Frequency High-Voltage Transformer Link for High-Power Magnetron Drive  

Science.gov (United States)

This paper presents a single lossless inductive snubber-assisted ZCS-PFM series resonant DC-DC power converter with a high-frequency high-voltage transformer link for industrial-use high power magnetron drive. The current flowing through the active power switches rises gradually at a turned-on transient state with the aid of a single lossless snubber inductor, and ZCS turn-on commutation based on overlapping current can be achieved in wide range pulse frequency modulation control scheme. The high-frequency high-voltage transformer primary side resonant current always becomes continuous operation mode, by electromagnetic loose coupling design of the high-frequency high-voltage transformer and the magnetizing inductance of the high-frequency high-voltage transformer. As a result, this high-voltage power converter circuit for the magnetron is possible to achieve a complete zero current soft switching under a condition of the broad width gate voltage signals. Furthermore, this high-voltage DC-DC power converter circuit can regulate the output power from zero to full over audible frequency range because of two resonant frequency circuit design. Its operating performances are evaluated and discussed on the basis of the power loss analysis simulation and the experimental results from a practical point of view.

Ishitobi, Manabu; Myoi, Takeshi; Soshin, Koji; Hiraki, Eiji; Nakaoka, Mutsuo

315

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

316

Impact of the control constraint on a buck converter design based on multi-objective optimization procedure  

Directory of Open Access Journals (Sweden)

Full Text Available The current paper deals with a multi-objective design approach of power converters applied to a DC-DC buck structure. This approch consists on optimizing a preselected power architecture by minimizing a multi-objective function (volume and time response) under multi-physic constraints (efficiency, thermal, electromagnetic compatibility and control). This multi-objective optimization allows evaluating the impact of the control aspect on the converter design by considering the control criteria with the same importance as the conventional constraints. The obtained results confirm the influence of the control on the converter design parameters. They help the designer to choose suitable operating points depending on the desired performances in terms of volume and time response while respecting efficiency, junction temperatures and electromagnetic compatibility constraints.

Cherif Larouci; Kamal Ejjabraoui; Pierre Lefranc; Claude Marchand

2012-01-01

317

On-chip frequency compensation with a dual signal path operational transconductance amplifier for a voltage mode control DC/DC converter  

International Nuclear Information System (INIS)

A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented. By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA), the proposed circuit generates two zeros to realize high closed-loop stability. Meanwhile, full on-chip integration is also achieved due to its simple structure. Hence, the number of off-chip components and the board space is greatly reduced. The structure of the dual signal path OTA is also optimized to help get a better transition response. Implemented in a 0.5 ?m CMOS process, the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability. The test results show that both load and line regulations are less than 0.3%, and the output voltage can be recovered within 15 ?s for a 400 mA load step. Moreover, the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%. The efficiency of the whole chip can be up to 95%. (semiconductor integrated circuits)

2012-04-01

318

On-chip frequency compensation with a dual signal path operational transconductance amplifier for a voltage mode control DC/DC converter  

Science.gov (United States)

A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented. By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA), the proposed circuit generates two zeros to realize high closed-loop stability. Meanwhile, full on-chip integration is also achieved due to its simple structure. Hence, the number of off-chip components and the board space is greatly reduced. The structure of the dual signal path OTA is also optimized to help get a better transition response. Implemented in a 0.5 ?m CMOS process, the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability. The test results show that both load and line regulations are less than 0.3%, and the output voltage can be recovered within 15 ?s for a 400 mA load step. Moreover, the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%. The efficiency of the whole chip can be up to 95%.

Qiang, Ye; Jie, Liu; Bing, Yuan; Xinquan, Lai; Ning, Liu

2012-04-01

319

DC-DC voltage micro-converters for micro-systems applications; Microconvertisseurs de tension continu-continu pour des applications microsystemes  

Energy Technology Data Exchange (ETDEWEB)

This work belongs to the European Barmint project which final goal is the realization of a micro-system, implanted in the human body, and devoted to the regulation of the blood pressure of patients. The aim of this thesis is the realization of the miniaturized power supply of this micro-system. The different approaches allowing to reach the required voltage levels from the 3.5 V initial level are analysed first. A solution based on the integration of DC-DC converters with their control loop has been retained. A control loop based on a single-cycle control principle and completed with a technique of control of the maximum current has been applied for the first time to a boost converter in order to eliminate the disturbances coming from the output of the photovoltaic cells. A first prototype with a single converter and with such a control loop has been successfully built and validated. Then a full system has been built which comprises: a DC-DC converter with its control loop for the 5 V-130 mA power supply and two parallel converters with their control loop for the 60 V output supply. This loop comprises an energy saving circuit which switches on the converters only when required by the health situation of the patient. It includes also a charge pump circuit which allows to supply the different 5 V control loop blocks using the 3.5 V input voltage. The entire system represents a 17.5 mm{sup 2} silicon surface. The second part of this work concerns the integration of a coil on a silicon surface. Iron/nickel alloy deposits on silicon substrates have been obtained and characterized. (J.S.)

Senouci, N.

1998-07-01

320

DC-DC conversion powering schemes for the CMS tracker at Super-LHC  

International Nuclear Information System (INIS)

The CMS experiment at the Large Hadron Collider (LHC) at CERN, Geneva, houses the largest silicon strip tracker ever built. For the foreseen luminosity upgrade of the LHC, the Super-LHC, however, a completely new silicon tracker will have to be constructed. One out of several major improvements currently under consideration is the implementation of a track trigger, with tracking information being provided to the first level trigger. Such an intelligent tracker design, utilising fast digital readout electronics, will most certainly lead to an increased power consumption, compared to today's tracker. In combination with the desire to reduce the amount of passive material inside the tracking volume and the impracticality to exchange or even add additional supply cables, a novel powering scheme will be inevitable. In this article a powering scheme based on DC-DC conversion is proposed, and requirements for the DC-DC converters are discussed. Studies of important DC-DC converter quantities such as the power efficiency, conducted and radiated noise levels, and material budget are presented, and a possible implementation of DC-DC buck converters into one proposed track trigger layout is sketched.

2010-01-01

 
 
 
 
321

Closed Loop Control of Soft Switched Interleaved Buck Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Design, Modeling and Simulation of a closed loop control is presented for Interleaved Buck Converter with Soft Switching. The features of the closed loop system are to reduce the switching losses and load current sharing among the parallel connected converters. The control system of the converter is designed using PWM technique. In order to improve the transient response and dynamic stability of the converters, the controller parameters are designed based on current mode control. Resonant components thus designed enable the application of zero current switching for both the converters connected in parallel thereby maintaining greater efficiency and minimizing voltage and current oscillations. The system analysis, design and performance are verified through simulation using MATLAB/Simulink environment. The simulation approach reveals the high speed dynamic performance of the closed loop system designed using robust PID controller. The laboratory prototype of the Buck converter is developed to verify the controller platform using PIC16F877A microcontroller.

R. Shenbagalakshmi; Sree Renga Raja

2012-01-01

322

?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; Nasrudin Abd Rahim; Jeyraj Selvaraj

2013-01-01

323

Low output ripple DC-DC converter based on an overlapping dual asymmetric half-bridge topology  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new converter topology is described for applications requiring very low output current ripple. The proposed converter consists of two asymmetric half-bridge converters whose output voltages overlap in a finite interval of time. This converter provides well regulated and smooth dc output without th...

Liu, JCP; Poon, NK; Pong, BMH; Tse, CK

324

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; P.Swaminathan

2012-01-01

325

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

326

Interleaved soft-switched active-clamped L-L type current-fed half-bridge DC-DC converter for fuel cell applications  

Energy Technology Data Exchange (ETDEWEB)

In this paper, an interleaved soft-switched active-clamped L-L type current-fed half-bridge isolated dc-dc converter has been proposed. The L-L type active-clamped current-fed converter is able to maintain zero-voltage switching (ZVS) of all switches for the complete operating range of wide fuel cell stack voltage variation at full load down to light load conditions. Active-clamped circuit absorbs the turn-off voltage spike across the switches. Half-bridge topology maintains higher efficiency due to lower conduction losses. Soft-switching permits higher switching frequency operation, reducing the size, weight and cost of the magnetic components. Interleaving of the two isolated converters is done using parallel input series output approach and phase-shifted modulation is adopted. It reduces the input current ripple at the fuel cell input, which is required in a fuel cell system and also reduces the output voltage ripples. In addition, the size of the magnetic/passive components, current rating of the switches and voltage ratings of the rectifier diodes are reduced. (author)

Rathore, Akshay K. [Electrical Machines and Drives Research Lab, University of Wuppertal, Rainer Gruenter Str. 21, University Campus Freudenberg, 42119 Wuppertal, NRW (Germany)

2009-12-15

327

A NOVEL EFFICIENT SOFT SWITCHED TWO PORTS DC-DC BOOST CONVERTER WITH OPEN LOOP AND CLOSED LOOP CONTROL  

Directory of Open Access Journals (Sweden)

Full Text Available A multiport converter promises cost-effective, flexible and more efficient energy processing by utilizing only a single power stage. Multiport converters, a promising concept for alternative energy systems, have attracted increasing research interest recently. Zero Voltage Switching (ZVS) alleviates the switching losses and improves the converter overall efficiency. Zero voltage switching can be achieved with the help of coupled inductor which also regulates the input current during the load disturbances. To reduce the switching losses and henceforth to improve efficiency of converter system, Zero Voltage Switching (ZVS) is employed. . This paper presents a two output ports single stage boost converter with ZVS. The proposed multi output port converter with soft switching is simple and efficient. The analysis is carried out for open loop and closed loop control. The simulation results for the same are presented in this paper.

T.NageswaraRao; V.C. Veera Reddy

2012-01-01

328

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

329

Nonlinear Phenomena in Buck-Boost Power Factor Correction Converter  

Directory of Open Access Journals (Sweden)

Full Text Available Buck-Boost Power-Factor-Correction (PFC) converter with Average-Current-Model (ACM) control is a nonlinear circuit because of the multiplier using and large change in the duty cycle, so its stability analysis must be studied by nonlinear model. In this paper double averaging method is used for describing the model of this converter. By this model we would be able to explain the low frequency dynamics of the system and identify stability boundaries according to circuit parameters and also nonlinear phenomena of this converter are detected.

Mehrnoosh Vatani; Soodabeh Soleymani; Mehrdad Ahmadi Kamarposhti

2013-01-01

330

An integrated DC-DC step-up charge pump and step-down converter in 130 nm technology  

CERN Document Server

After the LHC luminosity upgrade the number of readout channels in the ATLAS Inner Detector will be increased by one order of magnitude and delivering the power to the front-end electronics as well as cooling will become a critical system issue. Therefore a new solution for powering the readout electronics has to be worked out. Two main approaches for the power distribution are under development, the serial powering of a chain of modules and the parallel powering with a DCDC conversion stage on the detector. In both cases switchedcapacitor converters in the CMOS front-end chips will be used. In the paper we present the design study of a step-up charge pump and a step-down converter. In optimized designs power efficiency of 85 % for the step-up converter and 92 % for the step-down converter has been achieved.

Bochenek, M; Faccio, F; Kaplon, J

2009-01-01

331

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

332

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; S.Suresh Kumar; S.Daison Stallon

2012-01-01

333

Design of Current Source Dc/Dc Converter for Interfacing a 5 Kw Pem Fuel Cell / Paaugstinoš? Str?vas Avota L?dzsprieguma P?rveidot?ja Izstr?de 5 Kw ?de?raža Degvielas Elementam  

Science.gov (United States)

In domestic applications the low DC output voltage of a hydrogen fuel cell used as the main power supply or a backup power source has to be matched to the level and frequency of the AC voltage of utility grid. The interfacing power converter system usually consists of a DC/DC converter and an inverter. In this work, a DC/DC step-up converter stage is designed for interfacing a 5kW proton exchange membrane (PEM) fuel cell. The losses of DC/DC conversion are estimated and, basing on the relevant analysis, the most appropriate configuration of converter modules is selected for a DC/DC converter stage of increased efficiency. The authors present the results of experimental analysis and simulation for the selected configuration of four double inductor step-up push-pull converter modules ?de?raža degvielas elementa invertoru sist?mas m?jsaimniec?bas pielietojumiem parasti sast?v no l?dzsprieguma paaugstin?šanas un invert?šanas mezgliem. Šis raksts ir velt?ts paaugstinoš? l?dzsprieguma p?rveidot?ja izstr?dei 5 kW protonu apmai?as membr?nas degvielas elementam. Rakst? izp?t?ts divu induktoru divtaktu str?vas avota paaugstinošais l?dzsprieguma p?rveidot?js, apl?kojot gan datormodel?šanas, gan eksperiment?los rezult?tus. Lai palielin?tu DC/DC p?rveidot?ja efektivit?ti var izmantot vair?kus p?rveidot?ja modu?us, kam ieejas savienotas paral?li un izej?s - virkne. Anal?ze Šaj? raksta ir veikta anal?ze, balstoties uz kuras var izv?lieties skaitu p?rveidot?j modu?u skaitu, kuri nodrošina vislab?ko efektivit?ti DC/DC p?rveidot?ja posm?. Kop?jais eksperiment?li noteiktais izstr?d?t?s degvielas elementa p?rveidot?ju sist?mas fizik?l? mode?a lietder?bas koeficients ir 93%

Andrei?iks, A.; Steiks, I.; Krievs, O.

2013-08-01

334

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; KAVERI.P.RATHOD; G.V.JAYARAMAIH

2012-01-01

335

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; 2)A 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; T. Manokaran

2012-01-01

336

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

337

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.

Yu Fang; Tengfei Wei; Liang He; Yong Xie; Yan Xing

2010-01-01

338

Modeling, analysis, and application of buck converters in discontinuous-input-voltage mode operation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

By adding a suitable LC filter to the input of a Buck converter, it is possible to force the converter into discontinuous-input-voltage mode operation. A Buck converter in this mode of operation has useful properties such as power factor correction and soft turn-off switching. The operation, modelin...

Lee, YS; Wang, SJ; Hui, SYR

339

Pulse Skipping Modulated Buck Converter - Modeling and Simulation  

Directory of Open Access Journals (Sweden)

Full Text Available Modeling and simulation results of a pulse skipping modulated buck converter for applications involving a source with widely varying voltage conditions with loads requiring constant voltage from full load down to no load is presented. The pulses applied to the switch are blocked or released on output voltage crossing a predetermined value. The regulator worked satisfactorily over a wide input voltage range with good transient response but with higher ripple content. Input current spectrum indicates a good EMI performance with crowding of components at audio frequency range for the se-lected switching frequency.

Ramamurthy Srinivasan; Vanaja Ranjan P.

2010-01-01

340

Synthesis of Nonlinear Control of Switching Topologies of Buck-Boost Converter Using Fuzzy Logic on Field Programmable Gate Array (FPGA)  

Directory of Open Access Journals (Sweden)

Full Text Available An intelligent fuzzy logic inference pipeline for the control of a dc-dc buck-boost converter was designed and built using a semi-custom VLSI chip. The fuzzy linguistics describing the switching topologies of the converter was mapped into a look-up table that was synthesized into a set of Boolean equations. A VLSI chip–a field programmable gate array (FPGA) was used to implement the Boolean equations. Features include the size of RAM chip independent of number of rules in the knowledge base, on-chip fuzzification and defuzzification, faster response with speeds over giga fuzzy logic inferences per sec (FLIPS), and an inexpensive VLSI chip. The key application areas are: 1) on-chip integrated controllers; and 2) on-chip co-integration for entire system of sensors, circuits, controllers, and detectors for building complete instrument systems.

Johnson A. Asumadu; Vaidhyanathan Jagannathan; Arkhom Chachavalnanont

2010-01-01

 
 
 
 
341

DC-DC Powering for the CMS Pixel Upgrade  

CERN Multimedia

The CMS experiment plans to replace its silicon pixel detector with a new one with improved rate capability and an additional detection layer at the end of 2016. In order to cope with the increased number of detector modules the new pixel detector will be powered via DC-DC converters close to the sensitive detector volume. This paper reviews the DC-DC powering scheme and reports on the ongoing R and D program to develop converters for the pixel upgrade. Design choices are discussed and results from the electrical and thermal characterisation of converter prototypes are shown. An emphasis is put on system tests with up to24 converters. The performance of pixel modules powered by DC-DC converters is compared to conventional powering. The integration of the DC-DC powering scheme into the pixel detector is described and system design issues are reviewed.

Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Rittich, David Michael; Sammet, Jan Domenik; Wlochal, Michael

2013-01-01

342

Integrated design & control of a buck boost converter  

Directory of Open Access Journals (Sweden)

Full Text Available 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 approach 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

2009-01-01

343

Separately-controlled single-ended quasi-current resonant DC/DC converter with HF-link incorporating forward and flyback hybrid transformer. Koshuha forward/flyback konsei hen prime atsuki link wo motsu tasei isseki denryu kyoshingata DC/DC converter  

Energy Technology Data Exchange (ETDEWEB)

High frequency quasi-current resonant type soft-switching DC/DC power converter circuits technique is becoming one of the necessary power basic technique for realization of minimizing efficiently and simultaneously high frequency switching losses of a power semiconductor device, transitional reactance of dv/dt as wellas di/dt and EMI/RFI noisy level. In this paper, the captioned converter (SMPS) topology having improved form of quasi-current resonant/zero-current soft switching (ZCS) pattern of a conventional forward high frequency transformer link is proposed and its action principle as well as characteristics are demonstrated. Namely, with performance of a computer-aid simulating analysis, the open-loop/closed loop steady-state voltage regulation characteristics and ZCS realization parameters of present circuits are illustrated and estimated based upon their relationship to normalized controlling frequency as well as various normalized circuits parameters in a common feasible manner. Consequently, various data being necessary in the fore-stage of the present design are supplied. 7 refs., 18 figs., 1 tab.

Lu, D.; Nakaoka, M. (Kobe Univ., Kobe (Japan))

1991-12-20

344

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)

2012-01-01

345

A ripple-mitigating pre-amplifier based on interleaved DC-DC boost converters for efficiency improvement/ Pre-Amplificador de potencia basado en conexión paralela de convertidores DC-DC para reducción de rizados de corriente e incremento de eficiencia  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Este artículo propone un pre-amplificador basado en convertidores DC-DC conectados en paralelo para la reducción de armónicos inyectados a fuentes de potencia. Las principales características del pre-amplificador son la reducción del rizado de corriente de entrada en convertidores de potencia, incrementado además la eficiencia del sistema de conversión. Se describe el cálculo de las condiciones óptimas de operación del pre-amplificador, así como su modelado mat (more) emático y control para operar en las condiciones seleccionadas. Así mismo, se analiza el pre-amplificador con un convertidor elevador clásico, obteniendo una reducción significativa en el rizado de corriente inyectado a la fuente, así como un incremento en la eficiencia del sistema. Finalmente, los análisis teóricos se confirman a través de simulaciones circuitales y resultados experimentales. Abstract in english An efficient pre-amplifier based on interleaved DC-DC boost switching converters to mitigate high-frequency harmonics injection to power sources is proposed. The main features of the pre-amplifier are mitigate the ripple of power converters input-current and improving the efficiency of the whole power conversion chain. The pre-amplifier optimal operating conditions are calculated, and the circuit is modeled and controlled to operate in such conditions. The pre-amplifier i (more) nteracting with a classical single boost is analyzed, obtaining a strong reduction in the current ripple injected to the source, and also improving the efficiency of the initial conversion system. Finally, the theoretical analyses are confirmed by means of circuital PSIM simulations and experimental results.

Arango, Eliana; Ramos-Paja, Carlos; Carrejo, Carlos; Giral, Roberto; Saavedra-Montes, Andres

2011-09-01

346

Design Considerations for High Step-Down ratio Buck Regulators  

CERN Document Server

The buck or step-down DC-DC converter is the workhorse switching power supply topology. It utilizes two switches (two FETS or one FET and one diode) along with an output inductor and output capacitor. Whether you look at a large computer server, a personal desktop or a laptop computer, a cell phone or a GPS unit all will contain a buck converter in one form or another. This paper will discuss the synchronous buck topology, design considerations, component selection followed by a small signal model of buck converter. Issues that are important in optimizing the efficiency of the design for example MOSFET selection, the impact that the MOSFET driver plays in improving the efficiency will be examined. The paper will finish by contrasting various control architectures.

Khanna, R

2008-01-01

347

DC-DC Conversion Powering for the CMS Tracker at SLHC  

CERN Multimedia

A tracker powering scheme based on DC-DC converters close to the detector modules can supply more power through thinner cables. This will allow to satisfy the increased power demands of tracking systems at the SLHC. This article describes the development of DC-DC converters for upgrades of the CMS pixel and tracking systems and addresses system integration issues.

Feld, Lutz

2010-01-01

348

Improved control strategy on buck-type converter with power factor correction scheme  

Energy Technology Data Exchange (ETDEWEB)

Buck-type high-power-factor PWM active converter topology is not only sufficiently capable for the effective elimination of input current harmonics, but also its characteristics include high efficiency, absence of inrush current, the capability to obtain low DC output voltage, ability to protect against short circuit, and so force. The buck-type high-power-factor converter has the inherent capability to become attractive power supplies for telecommunications energy systems. On the other hand, because this type of converter must employ high-inductance reactors, these tend to increase equipment in size and weight, and this has prevented their widespread use. This paper presents a new control strategy for buck-type high-power-factor PWM converter which can reduce the size and weight of reactor and also eliminate the ripple component included into output voltage. The operating principle and simulation results are described.

Hirachi, Katsuya; Iwade, Touru [Yuasa Corp., Takatsuki, Osaka (Japan). Research and Development Div.; Mii, Takanori; Yasutsune, Hidenobu; Nakaoka, Mutsuo [Yamaguchi Univ., Ube, Yamaguchi (Japan). Dept. of Electrical and Electronics Engineering

1995-12-31

349

A QRC-ZCS-PWM buck converter using a non-linear resonant inductor  

Energy Technology Data Exchange (ETDEWEB)

This paper shows a loss-less commutation cell that uses a non-linear resonant inductor. The principle of the non-linear resonant inductor is applied to a QRC-ZCS-PWM buck converter with objective of reducing the peak current in the main switch, maintaining the ZCS characteristics of the QRC-ZCS-PWM buck converter. This is achieved by un-saturating the core of the non-linear resonant inductor limiting its peak value. Mathematical equations, circuit operation and experimental results are also presented 4 refs., 16 figs., 1 tab.

Paiva, Elcio Precioso de; Freitas, Luiz Carlos de; Farias, Valdeir Jose; Coelho, Ernane Antonio Alves; Vieira Junior, Joao Batista [Uberlandia Univ., MG (Brazil). Dept. de Engenharia Eletrica

1995-12-31

350

A Single Stage High Power Factor Supply Based on Integrated Buck Flyback Converter  

Directory of Open Access Journals (Sweden)

Full Text Available In recent years, power converters are used to get high power factor. This paper presents an integrated converter topology for driving HB LEDs which provides high power factor. The integrated buck flyback converter is a single stage, low cost, high power factor AC-DC converter with fast output regulation. The converter is used to provide power factor correction in streetlight application. To obtain high power factor, the buck stage and flyback stage are operated in discontinuous mode. Dimming operation of HB LED is also described. A closed loop is used for enabling the PWM dimming. The simulation studies using MATLAB/Simulink is also presented. Hardware setup of open loop is described.

ELIZABETH PAUL; PROF. ALEYAS M.V; PROF. ANNIE P.OOMMEN

2013-01-01

351

Analysis of a high-voltage-gain hybrid switched-capacitor buck converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents an analysis on the effect of having different number of capacitors n in the first-stage switched-capacitor circuit of an improved hybrid switched-capacitor buck converter for high-voltage-gain conversion. Various aspects of the topology, operation, and efficiency are investigated...

Xiong, S; Tan, SC; Wong, SC

352

Analysis and design of a high-voltage-gain hybrid switched-capacitor buck converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents an analysis on the effect of having different number of capacitors n in the first-stage switched-capacitor circuit of an improved hybrid switched-capacitor buck converter for high-voltage-gain conversion. Various aspects of the topology, operation, and efficiency are investigated...

Xiong, S; Tan, SC; Wong, SC

353

On the practical design of a sliding mode voltage controlled buck converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents a simple and systematic approach to the design of a practical sliding mode voltage controller for buck converters operating in continuous conduction mode. Various aspects of the design, including the associated practical problems and the proposed solutions, are detailed. A simple...

Tan, SC; Lai, YM; Cheung, MKH; Tse, CK

354

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

Science.gov (United States)

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.

Wang, Fa-Qiang; Ma, Xi-Kui

2013-03-01

355

On the Suitability of Interleaved Switched Capacitor Converter as an Interface for Electric Vehicle Dual Energy Storage Systems  

Energy Technology Data Exchange (ETDEWEB)

This paper presents the analysis and novel hybrid controller design for an interleaved 2-quadrant switched capacitor (SC) bidirectional DC/DC converter for a hybrid electric vehicle (HEV) dual energy storage system. The designed novel control strategy enables simpler dynamics compared to a standard buck converter with input filter, good regulation capability, low EMI, lower source current ripple, ease of control, and continuous input current waveform in both buck as well as boost modes of operation.

Amjadi, Zahra; Williamson, Sheldon

2010-09-15

356

Closed-Form Critical Conditions of Saddle-Node Bifurcations for Buck Converters  

CERN Multimedia

A general and exact critical condition of saddle-node bifurcation is derived in closed form for the buck converter. The critical condition is helpful for the converter designers to predict or prevent some jump instabilities or coexistence of multiple solutions associated with the saddle-node bifurcation. Some previously known critical conditions become special cases in this generalized framework. Given an arbitrary control scheme, a systematic procedure is proposed to derive the critical condition for that control scheme.

Fang, Chung-Chieh

2012-01-01

357

Analysis and Design of 3.3 kV IGBT Based Three-Level DC/DC Converter with High-Frequency Isolation and Current Doubler Rectifier  

Science.gov (United States)

The paper presents the findings of a R&D project connected to the development of auxiliary power supply (APS) for the high-voltage DC-fed rolling stock applications. The aim was to design a new-generation power converter utilizing high-voltage IGBT modules, which can outpace the predecessors in terms of power density, i.e. to provide more power for smaller volumetric space. The topology proposed is 3.3 kV IGBT-based three-level neutral point clamped (NPC) half-bridge with high-frequency isolation transformer and current doubler rectifier that fulfils all the targets imposed by the designers. Despite an increased component count the proposed converter is very simple in design and operation. The paper provides an overview of the design with several recommendations and guidelines. Moreover, the simulation and experimental results are discussed and the performance evaluation of the proposed converter is presented.

Vinnikov, Dmitri; Jalakas, Tanel; Roasto, Indrek

2009-01-01

358

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 10m...

Degrenne, Nicolas; Allard, Bruno; Buret, François; Morel, Florent; Adami, Salah-Eddine; Labrousse, Denis

359

System Test Measurements with a DC-DC Conversion Powering Scheme for the CMS Tracker at SLHC  

CERN Document Server

A potential luminosity upgrade of the LHC, the so-called SLHC implies challenging upgrades for the experiments at the LHC. Concerning the upgrade of the CMS silicon strip tracker, the delivery of power isconsidered to be one of the major challenges. The higher instantaneous luminosity makes an increase ingranularity and complexity of the device inevitable. Both are expected to result in a power consumptioncomparable or even higher than the power consumption of today’s strip tracker. However, the space availablefor cables will remain the same. In addition, a further increase of the tracker material budget due to cablesand cooling is considered unacceptable, as the performance of the CMS detector must not be compromisedfor the upgrade. Novel powering schemes such as serial powering or the usage of DC-DC converters havebeen proposed to solve the problem. To test the second option, substructures of the current CMS siliconstrip tracker have been operated for the ?rst time with o?-the-shelf DC-DC buck convert...

Sammet, Jan

2009-01-01

360

Advanced buck converter power supply ABCPS for APT  

International Nuclear Information System (INIS)

The United States Department of Energy (DOE) is planning to fabricate an Accelerator for the Production of Tritium (APT) at their Savannah River Site, to provide Tritium for national defense. The 1700 million electron volt (MeV) proton beam accelerator will be powered by radio frequency (RF) klystrons. A direct current (DC) power supply is required for each of the approximately two hundred and fifty 1-megawatt (MW) continuous wave klystrons in the RF power system. The requirements are that the power supply meet output performance specifications, provide fault protection for the klystron, have high efficiency, high reliability, good maintainability, and be readily manufacturable. As the power supplies are one of the largest cost elements in the accelerator, a technology review was made to determine the most economical approach to satisfy the requirements. A switch-mode power supply employing a buck-regulator was identified as being potentially the lowest cost approach. As the switch represents a certain development risk, a small-scale prototype has been constructed for evaluation, and has resulted in the decision to fabricate a full-scale prototype power supply. A description of the hardware will be presented

1998-01-01

 
 
 
 
361

DC/DC conversion circuit  

UK PubMed Central (United Kingdom)

DC/DC conversion circuit (1), comprising a transformer (2) having a primary winding (3), a secondary winding (4), and an auxiliary winding (5); a switching transistor (T), comprising a series circuit with the primary winding (3) between first and second direct current input terminals (6; 7); a start circuit (R1, C1) connected to a control electrode of the switching transistor (T) for switching the switching transistor (T) on by powering the direct current input terminals (6; 7); a control transistor connected to the control electrode of the switching transistor (T) for switching off the switching transistor (T) in dependence on a current flowing through the series circuit during operation.The auxiliary winding (5) and the control transistor (Q) connect to a voltage control circuit (8) for setting an output power provided at the secondary winding (4) of the transformer (2) during operation by a controlled switching-on of the switching transistor (T) in dependence on the magnitude of a current flowing in the primary winding (3). The conversion circuit (1) is arranged such that during operation via the auxiliary winding (5) a voltage required at the control electrode of the switching transistor (T) for on thereof is built up in a time period which is inversely proportional to the amount of output power provided at the secondary winding (4).

SCHETTERS CORNELIS JOHANNES ADRIANUS; LAMMERS JOHANNUS LEONARDUS EMMANUEL MARIA; BODEGRAVEN TIJMEN CORNELIS VAN; LAMMERS JOHANNUS EMMANUEL MARIA; VAN BODEGRAVEN TIJMEN CORNELIS

362

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

363

Design and simulation of fuzzy controlled quasi resonant buck converter  

Directory of Open Access Journals (Sweden)

Full Text Available A controller based on Fuzzy logic is implemented and its application to the regulation of power converter is investigated. Being free of complex equations and heavy computation, it achieves fast dynamic response and adapts to varying conditions of operation. The topology is modeled using MATLAB software and operated at finite higher switching frequency to evaluate its closed-loop performance in respect of line and load regulation. It is verified by transient characteristics that due to quasi-resonance there is a drastic change in peak overshoot and settling time and the proposed strategy has good rejection ability for supply and load disturbances.

A. Rameshkumar; S. Arumugam

2009-01-01

364

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

2013-01-01

365

An active current-sensing constant-frequency HCC buck converter using phase-frequency-locked techniques.  

Science.gov (United States)

A hysteresis-current-controlled (HCC) buck converter with active current-sensing and phase-frequencylocked techniques is presented in this paper. The proposed active current-sensing technique can not only consume less power than previous techniques, but also fully sense the inductor current. Although the buck converter is HCC, the switching frequency can be constant due to the devised phase-frequency-locked technique. The proposed converter has been designed and implemented with TSMC 0.35 microm DPQM CMOS processes. It is shown in the experimental results that the HCC buck converter features the following characteristics: 1) up to 800 mA of load current, 2) wide input and output voltage range, 3) high power efficiency, and 4) constant-frequency operation. PMID:18467220

Chen, Jiann-Jong

2008-04-01

366

An active current-sensing constant-frequency HCC buck converter using phase-frequency-locked techniques.  

UK PubMed Central (United Kingdom)

A hysteresis-current-controlled (HCC) buck converter with active current-sensing and phase-frequencylocked techniques is presented in this paper. The proposed active current-sensing technique can not only consume less power than previous techniques, but also fully sense the inductor current. Although the buck converter is HCC, the switching frequency can be constant due to the devised phase-frequency-locked technique. The proposed converter has been designed and implemented with TSMC 0.35 microm DPQM CMOS processes. It is shown in the experimental results that the HCC buck converter features the following characteristics: 1) up to 800 mA of load current, 2) wide input and output voltage range, 3) high power efficiency, and 4) constant-frequency operation.

Chen JJ

2008-04-01

367

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; Dr S. SATYA NARAYANA

2013-01-01

368

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

2012-01-01

369

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

370

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 battery chargers and similar devices use to get the maximum possible power from one or more solar panels. Among the different methods used to track the maximum power point, Perturb and Observe method is a type of strategy to optimize the power output of an array. In this method, the controller adjusts the voltage by a small amount from the array and measures power, if the power increases, further adjustments in that direction are tried until power no longer increases. In this research paper the system performance is optimized by perturb and observe method using buck boost converter. By varying the duty cycle of the buck boost converter, the source impedance can be matched to adjust the load impedance to improve the efficiency of the system. The Performance has been studied by the MATLAB/Simulink.

M.S.SIVAGAMAUNDARI, DR.P.MELBA MARY, V.K.VELVIZHI

2013-01-01

371

Performance Analysis of Trench Power MOSFETs in High-Frequency Synchronous Buck Converter Applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper investigates the performance perspectives and theoretical limitations of trench power MOSFETs in synchronous rectifier buck converters operating in the MHz frequency range. Several trench MOSFET technologies are studied using a mixed-mode device/circuit modeling approach. Individual power loss contributions from the control and synchronous MOSFETs, and their dependence on switching frequency between 500 kHz and 5 MHz are discussed in detail. It is observed that the conduction loss contribution decreases from 40% to 4% while the switching loss contribution increases from 60% to 96% as the switching frequency increases from 500 KHz to 5 MHz. Beyond 1 MHz frequency there is no obvious benefit to increase the die size of either SyncFET or CtrlFET. The RDS(ON)×QG figure of merit (FOM) still correlates well to the overall converter efficiency in the MHz frequency range. The efficiency of the hard switching buck topology is limited to 80% at 2 MHz and 65% at 5 MHz even with the most advanced trench MOSFET technologies.

Yali Xiong; Xu Cheng; Xiangcheng Wang; Pavan Kumar; Lina Guo; Z. John Shen

2008-01-01

372

Theoretical assessment of the maximum power point tracking efficiency of photovoltaic facilities with different converter topologies  

Energy Technology Data Exchange (ETDEWEB)

The operating point of a photovoltaic generator that is connected to a load is determined by the intersection point of its characteristic curves. In general, this point is not the same as the generator's maximum power point. This difference means losses in the system performance. DC/DC converters together with maximum power point tracking systems (MPPT) are used to avoid these losses. Different algorithms have been proposed for maximum power point tracking. Nevertheless, the choice of the configuration of the right converter has not been studied so widely, although this choice, as demonstrated in this work, has an important influence in the optimum performance of the photovoltaic system. In this article, we conduct a study of the three basic topologies of DC/DC converters with resistive load connected to photovoltaic modules. This article demonstrates that there is a limitation in the system's performance according to the type of converter used. Two fundamental conclusions are derived from this study: (1) the buck-boost DC/DC converter topology is the only one which allows the follow-up of the PV module maximum power point regardless of temperature, irradiance and connected load and (2) the connection of a buck-boost DC/DC converter in a photovoltaic facility to the panel output could be a good practice to improve performance. (author)

Enrique, J.M.; Duran, E.; Andujar, J.M. [Departamento de Ingenieria Electronica, de Sistemas Informaticos y Automatica, Universidad de Huelva (Spain); Sidrach-de-Cardona, M. [Departamento de Fisica Aplicada, II, Universidad de Malaga (Spain)

2007-01-15

373

Parasitic Effects on the Performance of DC-DC SEPIC in Photovoltaic Maximum Power Point Tracking Applications  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper presents an analysis of the effect of parasitic resistances on the performance of DC-DC Single Ended Pri- mary Inductor Converter (SEPIC) in photovoltaic maximum power point tracking (MPPT) applic...

Nur Mohammad; Muhammad Quamruzzaman; Mohammad Rubaiyat Tanvir Hossain; Mohammad Rafiqul Alam

374

Sampled-Data and Harmonic Balance Analyses of Average Current-Mode Controlled Buck Converter  

CERN Document Server

Dynamics and stability of average current-mode control of buck converters are analyzed by sampled-data and harmonic balance analyses. An exact sampled-data model is derived. A new continuous-time model "lifted" from the sampled-data model is also derived, and has frequency response matched with experimental data reported previously. Orbital stability is studied and it is found unrelated to the ripple size of the current-loop compensator output. An unstable window of the current-loop compensator pole is found by simulations, and it can be accurately predicted by sampled-data and harmonic balance analyses. A new S plot accurately predicting the subharmonic oscillation is proposed. The S plot assists pole assignment and shows the required ramp slope to avoid instability.

Fang, Chung-Chieh

2012-01-01

375

Development of a state feedback controller for the synchronouns buck converter  

Directory of Open Access Journals (Sweden)

Full Text Available A digital control algorithm for a current-mode (CM) and a voltage-mode (VM) synchronous buck converter (SBC) is developed. In both cases, the design leads to a stable controller, even for a duty cycle larger than 50%. The desired output voltage and the transient response can be independently specified. Moreover, zero steady-state error in the output voltage can be obtained with the aid of additional dynamics. In both cases, the specification is done by pole placement using complete state feedback. A discrete-time model is used to design the feedback gains. Both the stability and the small-signal transient response are analyzed. In another paper (Oliva et al., 2003) the control algorithms are experimentally validated with a DSP-controlled SBC.

A. Oliva; H. Chiacchiarini; G. Bortolotto

2005-01-01

376

DC-DC Conversion Powering Schemes for the CMS Tracker at Super-LHC  

CERN Multimedia

The CMS experiment at the Large Hadron Collider (LHC) at CERN, Geneva, houses the largest silicon strip tracker ever built. For the foreseen luminosity upgrade of the LHC, the Super-LHC, however, a completely new silicon tracker will have to be constructed. One out of several major improvements currently under consideration is the implementation of a track trigger, with tracking information being provided to the first level trigger. Such an intelligent tracker design, utilising fast digital readout electronics, will most certainly lead to an increased power consumption, compared to today's tracker. In combination with the desire to reduce the amount of passive material inside the tracking volume and the impracticality to exchange or even add additional supply cables, a novel powering scheme will be inevitable. In this article a powering scheme based on DC-DC conversion is proposed, and requirements for the DC-DC converters are discussed. Studies of important DC-DC converter quantities such as th...

Klein, Katja; Jussen, Rüdiger; Karpinski, Waclaw; Merz, Jennifer; Sammet, Jan

2010-01-01

377

A Fully-Integrated Buck Converter Design and Implementation for On-Chip Power Supplies  

Directory of Open Access Journals (Sweden)

Full Text Available A 5V-2.5V fully-integrated low-power buck converter was designed and implemented using 0.5µm CMOS technology. The critical circuits of the high frequency controller and an on-chip multi-layer spiral inductor were presented. The structure of multi-layer spiral inductor having parallel and series branches of the metal strip. As the result that the parallel branching structure greatly reduced the series resistance and the series branching structure greatly improved the series inductance of the inductor, the structure can achieve quality factor and current capability enhancement while compatible with conventional CMOS process. The quality factor was quantitatively analyzed with a scalable model and its origin was investigated at a structural point of view. From chip measurement results, when the converter is running at the rated load, the average output voltage of 2.5V, the output voltage ripple within ±2%, and the energy efficiency of 46% are achieved.

Qinghua Li

2012-01-01

378

Fast-Scale and Slow-Scale Subharmonic Oscillation of Valley Current-Mode Controlled Buck Converter  

Science.gov (United States)

A valley current-mode (VCM) controlled buck converter with current source load (CSI) has complex phenomena of fast-scale and slow-scale subharmonic oscillations. The piecewise smooth switching model of the VCM controlled buck converter with CSI is established. It is found that attractive regions of fast-scale and slow-scale subharmonic oscillations exist in the bifurcation diagram, and two tori exist in the corresponding Poincaré mapping. The research results by time-domain simulation indicate that U-type subharmonic oscillation (SO) constituted by SO and frequency-reduced subharmonic oscillation (FSO) exists in inductor current, and sine-type SO constituted by fast scale and low scale exists in output voltage respectively. Experimental results are given to verify the analysis and simulation results.

Zhou, Guo-Hua; Xu, Jian-Ping; Bao, Bo-Cheng; Zhang, Fei; Liu, Xue-Shan

2010-09-01

379

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 have lower switching losses and minimum ringing voltage of the active switches. Thus, the proposed IBCC with active-clamp circuits for wind energy conversion can significantly increase conversion efficiency. Finally, a 240 W prototype of the proposed IBCC with active-clamp circuits was built and implemented. Experimental results have shown that efficiency can reach as high as 91%. The proposed IBCC with active-clamp circuits is presented in high step-down voltage applications to verify the performance and the feasibility for energy conversion of wind turbines.

Cheng-Tao Tsai; Chih-Lung Shen

2012-01-01

380

Design of anti-jamming current-sensing circuit for current-mode buck regulator  

Energy Technology Data Exchange (ETDEWEB)

A novel anti-jamming integrated CMOS current-sensing circuit for current-mode buck regulators is presented. Based on the widely-used traditional current-sensing structure, anti-jamming performance is improved significantly by adding on-chip capacitors and one-shot circuit. Also the transient response is faster through the introduction of current offset. The circuit is concise, simple to implement and suits for SoC applications with single power supply. A dual-output current-mode DC-DC buck converter with proposed structure has been fabricated with a 0.5 mum CMOS process for validation. In the 2.5-5.5 V input range, the two channels work steadily in the load current range of 0-600 mA. And the measured maximum efficiency is up to 96%.

Yuan Bing; Lai Xinquan; Ye Qiang [Institute of Electronic CAD, Xidian University, Xi' an 710071 (China); Li Yanming; Jia Xinzhang, E-mail: yuanbing1983@126.co, E-mail: byuan@mail.xidian.edu.c [School of Microelectronics, Xidian University, Xi' an 710071 (China)

2009-04-15

 
 
 
 
381

Design of anti-jamming current-sensing circuit for current-mode buck regulator  

International Nuclear Information System (INIS)

A novel anti-jamming integrated CMOS current-sensing circuit for current-mode buck regulators is presented. Based on the widely-used traditional current-sensing structure, anti-jamming performance is improved significantly by adding on-chip capacitors and one-shot circuit. Also the transient response is faster through the introduction of current offset. The circuit is concise, simple to implement and suits for SoC applications with single power supply. A dual-output current-mode DC-DC buck converter with proposed structure has been fabricated with a 0.5 ?m CMOS process for validation. In the 2.5-5.5 V input range, the two channels work steadily in the load current range of 0-600 mA. And the measured maximum efficiency is up to 96%.

2009-01-01

382

A Multi-Level Grid Interactive Bi-directional AC/DC-DC/AC Converter and a Hybrid Battery/Ultra-capacitor Energy Storage System with Integrated Magnetics for Plug-in Hybrid Electric Vehicles  

Energy Technology Data Exchange (ETDEWEB)

This study presents a bi-directional multi-level power electronic interface for the grid interactions of plug-in hybrid electric vehicles (PHEVs) as well as a novel bi-directional power electronic converter for the combined operation of battery/ultracapacitor hybrid energy storage systems (ESS). The grid interface converter enables beneficial vehicle-to-grid (V2G) interactions in a high power quality and grid friendly manner; i.e, the grid interface converter ensures that all power delivered to/from grid has unity power factor and almost zero current harmonics. The power electronic converter that provides the combined operation of battery/ultra-capacitor system reduces the size and cost of the conventional ESS hybridization topologies while reducing the stress on the battery, prolonging the battery lifetime, and increasing the overall vehicle performance and efficiency. The combination of hybrid ESS is provided through an integrated magnetic structure that reduces the size and cost of the inductors of the ESS converters. Simulation and experimental results are included as prove of the concept presenting the different operation modes of the proposed converters.

Onar, Omer C [ORNL

2011-01-01

383

Usage of a dc-to-dc converter for voltage adaption between energy storage and propulsion system in electric or hybrid vehicles; Einsatz eines DC/DC-Wandlers zur Spannungsanpassung zwischen Antrieb und Energiespeicher in Elektro- und Hybridfahrzeugen  

Energy Technology Data Exchange (ETDEWEB)

Every time a new hybrid or electrical vehicle is developed, different topologies are compared to achieve the best results regarding weight costs and efficiency. The integration of a dc-to-dc converter between the battery stack and the power train is a frequently discussed alternative because the preferred voltage of the inverter and machine are often higher than the voltage of the battery stack. Within this thesis this approach was studied in detail and compared with the conventional concept without using a dc-to-dc converter. Therefore the influence of the dc-link voltage on the components like battery stack, machine, inverter and dc-to-dc converter was investigated. A change of the dc-link voltage leads to changes inside the components which affect weight, surface of the semiconductor devices and efficiency. This correlation could be used to develop a simulation process which optimizes the dc-link voltage regarding the programmed targets. In hybrid and electrical vehicles low weight and minimum costs are important and were defined as the main targets to achieve. The vantages which arise by using a dc-to-dc converter can be opposed to the disadvantages which also occur. The additional degree of freedom caused by the dc-to-dc converter shall be used. To achieve the best results regarding efficiency, the dc-link voltage has to be adapted to the operating point of the machine. First of all the dc-to-dc converter is an additional component with its weight, volume and losses. By the increased dc-link voltage on the drive train side, the size of the semiconductor devices inside the inverter could be reduced. Therefore the number of windings inside the machine has to be adapted accordingly. Also the wiring could be decreased based on the reduced currents. Overall there is still a higher weight and volume caused by the dc-to-dc converter. Also the efficiency map is influenced by the dc-to-dc converter. In the base speed region the dc-to-dc converter leads to a higher efficiency because the inverter currents should be reduced by the increased voltage. At high speed and especially high load the double energy conversion leads to a reduced efficiency. Whether a dc-to-dc converter is beneficial for traction systems depends highly on the distribution of the operating points. An inverter with an integrated dc-to-dc converter was developed and constructed for the ''Europa-Hybrid'' project. This hybrid vehicle project was public funded by the German Federal Ministry of Economics and Technology (BMWi). The inverter and the dc-to-dc converter where used to verify the simulation results. Within this thesis the factors of influence, which are in correlation with the dc-link voltage, were analyzed and depicted. The pros and cons of the dc-to-dc converter between the battery and the drive train where pointed out accordingly. (orig.)

Schoenen, Timo

2011-07-01

384

DC-DC Conversion Powering Schemes for the CMS Tracker Upgrade  

CERN Multimedia

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

385

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

CERN Multimedia

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

386

Full-bridge type electric converter study using the ZVS-PWM-GEPAE commutation auxiliary cell; Estudo do conversor DC/DC do tipo full-bridge empregando a celula auxiliar de comutacao ZVS-PWM-GEPAE  

Energy Technology Data Exchange (ETDEWEB)

This work presents the analysis and design procedures of a new D C-D C Full Bridge PWM converter, using the ZVS-PWM-GEPAE commutation cell to achieve soft switching. Experimental results obtained from a laboratory prototype rated 1500 W area also presented. It is demonstrated that the inclusion of the auxiliary switches do not modify the PWM switching pattern. Bench tests on the prototype confirm that the proposed circuit exhibits high efficiency and behaves as a constant voltage source over an extended power output range. (author)

Castaldo, Fernando Cardoso

1994-07-01

387

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

388

A Novel Three-Level ZVS PWM Inverter Topology for High-Voltage DC/DC Conversion Systems with Balanced Blocking Voltage Sharing and Wider Load Range  

Energy Technology Data Exchange (ETDEWEB)

As the Three-Level(TL) ZVS PWM DC/DC converter operate likewise Full-Bridge(FB) ZVS PWM DC/DC converters and the blocking voltage of each switching device of TL ZVS PWM DC/DC converters is a half of the DC-link voltage, they are suitable for the high input voltage applications. However, they have some problems as follows; the blocking voltages between inner and outer switching devices are unbalanced and it causes the power losses of the inner switching devices to be increased. Also, they have a limited load range so that the switching losses are increased and the efficiency is reduced as it goes to the light load. This paper presents a novel TL ZVS PWM DC/DC converter, which can eliminate the unbalance of the blocking voltage sharing between the switches at turn-off due to the stray inductances, and operate from no load to full load, The characteristics and performances of the proposed TL ZVS PWM DC/DC converter are verified by simulations and experimental results. (author). refs., figs.

Song, In Ho [POSCON (Korea, Republic of); Yoo, Sang Bong; Hyun, Dong Seok [Hanyang University (Korea, Republic of)

1997-04-15

389

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; Alfonso Alzate Gómez

2010-01-01

390

Analysis of Limit Cycles in a PI Digitally Controlled Buck Converter  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Digital control of power converters has been an area of considerable research interest in recent times. One of the problems which arises in these systems is that of the limit cycle oscillations that occur due to quantization in the feedback loop. This paper investigates the limit cycle oscillations ...

Bradley, Mark; Alarcon, E.; Feely, Orla

391

Nuevo sistema de control para el seguimiento del punto de máxima potencia en paneles solares basado en el control predictivo de corriente de convertidores cc-cc/ New control system for maximum power point tracking in solar panels based on dc-dc converter predictive current control  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Para obtener la máxima energía de un panel solar es necesario operarlo en el punto de máxima potencia, donde el producto de la tensión fotovoltaica generada y la corriente extraída es un máximo. En operación normal este punto cambia continuamente, lo que requiere de un sistema de seguimiento del punto de máxima potencia para optimizar la operación del panel. Los paneles solares presentan una característica no lineal en la curva corriente-voltaje, lo que hace dif (more) ícil la utilización de algoritmos convencionales de seguimiento de puntos de operación donde se busca un máximo o un mínimo. Se ha demostrado que el algoritmo ?perturbar y observar? (P&O) es adecuado para el seguimiento del punto de máxima transferencia de potencia sobre este sistema. Este trabajo presenta una simulación en Matlab Simulink del comportamiento del panel solar bajo irradiancias y temperaturas típicas. El modelo se usa para probar que un sistema de seguimiento del punto de máxima potencia del panel basado en el algoritmo P&O operando sobre un control predictivo de corriente aplicado a un convertidor CC-CC es capaz de encontrar y seguir eficientemente el punto de máxima transferencia de potencia frente a variaciones en las condiciones de irradiancia y temperatura en el panel. Abstract in english To get maximum energy from a solar panel it is necessary to operate in the maximum power point where the product of generated photovoltage and extracted current is a maximum. In normal operation this point changes continuously, therefore a maximum power point tracking system is required. Solar panels present a nonlinear characteristic in the current-voltage graph, complicating the use of standard operating point tracking algorithms to find a maximum power point. If has be (more) en shown that the "perturb and observe" (P&O) algorithm is adequate to achieve this task. This work presents a Simulink Matlab simulation of the solar panel behavior under constant irradiation and typical temperatures. This simulation is used to prove that a maximum power point tracking control based on the P&O algorithm manipulating a predictive current control applied to a DC-DC converter is able to find and efficiently follow the maximum power point under panel irradiance and temperature variations.

Baethge, Erick; Berzoy, Alberto; Guzmán, Víctor; Giménez, María Isabel

2011-09-01

392

Closed-Form Critical Conditions of Subharmonic Oscillations for Buck Converters  

CERN Multimedia

A general critical condition of subharmonic oscillation in terms of the loop gain is derived. Many closed-form critical conditions for various control schemes in terms of converter parameters are also derived. Some previously known critical conditions become special cases in the generalized framework. Given an arbitrary control scheme, a systematic procedure is proposed to derive the critical condition for that control scheme. Different control schemes share similar forms of critical conditions. For example, both V2 control and voltage mode control have the same form of critical condition. A peculiar phenomenon in average current mode control where subharmonic oscillation occurs in a window value of pole can be explained by the derived critical condition. A ripple amplitude index to predict subharmonic oscillation proposed in the past research has limited application and is shown invalid for a converter with a large pole.

Fang, Chung-Chieh

2012-01-01

393

Stability Constrained Efficiency Optimization for Droop Controlled DC-DC Conversion System  

DEFF Research Database (Denmark)

Paralleled dc converter systems are widely used in distribution systems and uninterruptable power supplies. This paper implements a hierarchical control in a droop-controlled dc-dc conversion system with special focus on improving system efficiency which is dealt within the tertiary regulation. As the efficiency of each converter changes with output power, virtual resistances (VRs) are set as decision variables for adjusting power sharing proportion among converters. It is noteworthy that apart from restoring the voltage deviation, secondary control plays an important role to stabilize dc bus voltage when implementing tertiary regulation. Moreover, system dynamic is affected when shifting VRs. Therefore, the stability is considered in optimization by constraining the eigenvalues arising from dynamic state space model of the system. Genetic algorithm is used in searching for global efficiency optimum while keeping stable operation. Simulation results are shown to demonstrate the effectiveness of the method.

Meng, Lexuan; Dragicevic, Tomislav

2013-01-01

394

Análisis y comparación entre un controlador PI difuso y un controlador PI óptimo convencional para un conversor reductor Analysing and comparing a PI fuzzy controller and an optimal conventional PI controller for a buck converter  

Directory of Open Access Journals (Sweden)

Full Text Available nente. Tal tipo de dispositivos de electrónica de potencia convierten una tensión continua a otra de menor magnitud y cuyas ca- racterísticas de no linealidad son evidenciadas. Se presentan entonces, dos técnicas de control no lineal, la primera propuesta es un control óptimo PI (error proporcional e integral del error) convencional, basado en la minimización del criterio ITSE (integral del cuadrado del error ponderado en el tiempo). Para ello se obtiene un modelo de la planta en un punto de operación. La se- gunda propuesta es un control difuso cuyos conjuntos de entrada y salida son también definidos minimizando el criterio ITSE en el sistema general, y estableciendo como entradas el error proporcional y la integral del error. A continuación se realiza una va- riación de la carga para establecer la eficiencia del sistema con los dos controladores mencionados. Se debe tener en cuenta que este tipo de sistemas no debe presentar sobretensiones considerables, ya que puede ocasionar daño en él. En este sentido, los parámetros encontrados en el diseño de los dos controladores corresponden a una metodología analítica y descriptiva. Los resultados obtenidos en simulación, y estableciendo como figura de mérito el índice de desempeño mencionado (ITSE) y el con- sumo de potencia, muestra que la respuesta del sistema para el control difuso presenta un mayor consumo de potencia que el control óptimo, mientras que el ITSE obtenido es mayor para el control óptimo que para el difuso. Se concluye que la explora- ción de este tipo de conversores, utilizando técnicas de control no lineal y minimizando los diferentes índices de desempeño, es aplicable.This document proposes analysing and designing two control strategies for permanent current DC-DC buck converter. These kinds of electronic devices convert a constant-voltage to a lower constant-voltage (nonlinearity characteristics being demonstra- ted). Two nonlinear control techniques are shown. The first is a conventional optimal proportional error and integral error (PI) controller based on minimising integral of time per squared errors (ITSE) criteria. A model of the plant at an operation point was thus obtained. The second one was fuzzy control where input and output sets were also defined by minimising ITSE criteria in the overall system and establishing inputs such as proportional error and integral error. Load was then varied to establish the system’s efficiency with both the aforementioned controllers. It must be borne in mind that such systems should not present super-voltage since this can cause damage. The parameters found in designing both controllers thus corresponded to analytical and descriptive methodology. Simulation results, the performance index mentioned above (ITSE) and power consumption showed that the sys- tem’s response for the fuzzy control drew more power consumption than the optimal controller; otherwise, obtained ITSE was lar- ger for the optimal control than the fuzzy control. It is concluded that exploring these types of converter is applicable when using nonlinear control techniques and minimising the different performance indices.

Morales Laguado Lina; Chamorro Harold; Soriano Jairo

2009-01-01

395

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

396

Digitally Controlled Point of Load Converter with Very Fast Transient Response  

DEFF Research Database (Denmark)

This paper presents a new Digital Self-Oscillating Modulator (DiSOM) that allows the duty cycle to be changed instantly. The DiSOM modulator is shown to have variable switching that is a function of the duty cycle. Compared to a more traditional digital PWM modulator based on a counter and comparator the DiSOM modulator allows the sampling frequency of the output voltage control loop to be higher than the switching frequency of the power converter, typically a DC/DC converter. The features of the DiSOM modulator makes it possible to design a digitally controlled DC/DC converter with linear voltage mode control and very fast transient response. The DiSOM modulator is combined with a digital PID compensator algorithm is implemented in a hybrid CPLD/FPGA and is used to control a synchronous Buck converter, which is used in typical Point of Load applications. The computational time is only three clock cycles from the time the A/D converter result is read by the control algorithm to the time the duty cycle command is updated. A typical POL converter has been built and the experimental results show that the transient response of the converter is very fast. The output voltage overshoot is only 2.5% of the nominal output voltage when a load step of 50% - 100% of nominal output current is applied to the converter. The settling time is approximately 8 PWM cycles.

Jakobsen, Lars TØnnes; Andersen, Michael Andreas E.

2007-01-01

397

Design of interleaved multilayer rosen type piezoelectric transformer for high voltage dc/dc applications  

DEFF Research Database (Denmark)

Research and development within piezoelectric transformer (PT) based converters are rapidly increasing as the technology is maturing and starts to prove its capabilities. Especially for high voltage and high step-up applications, PT based converters have demonstrated good performance and DC/AC converters are widely used commercially. The availability of PT based converters for DC/DC applications are very limited and are not that developed yet. I this paper an interleaved multi layer Rosen-type PT for high step-up and high output voltage is developed, for driving a 2.5kV dielectric electro active polymer actuator [17]. The targeted application utilises an inductor-less half-bridge driving topology, where the reward of eliminating the series inductor is a reduction in component count, size and price. The absence of a series inductance calls for other means to avoid large hard switching losses and obtain soft switching capabilities. This can be achieved by utilising an advantageous PT structure, which is the main advantage of the interleaved Rosen-type PT. Furthermore the design should be further optimised, in order to achieve soft switching capability. The goal of this paper is to develop a soft switching optimised PT, capable of generating output voltages higher than 2kV from a 24V supply voltage. Furthermore finite element method (FEM) has been the main tool through the PT development.

RØdgaard, Martin SchØler; Andersen, Thomas

2012-01-01

398

Parallel connection of high-power DC/DC power supply based on IGBT device  

International Nuclear Information System (INIS)

Parallel connection technique of DC/DC power supplies is adopted, and DC high-power supply is designed based on IGBT device, which can be used as the plasma displacement fast control power supply for EAST device. Based on the simulation and experiment, satisfactory dynamic and static performance of the DC/DC power supply was obtained. (authors)

2006-01-01

399

Reliability and performance studies of DC-DC conversion powering scheme for the CMS pixel tracker at SLHC  

CERN Multimedia

The upgrades of the Large Hadron Collider (LHC) introduce a significant challenge to the power distribution of the detectors. DC-DC conversion is the preferred powering scheme proposed to be integrated for the CMS tracker to deliver high input voltage levels and performing a step-down conversion nearby the detector modules. In this work, we propose a step-up/step-down powering scheme by performing voltage step up at the CAEN supply unit and voltage step down near the detector. We designed step-up converters and investigate the pixel performance and power loss on the FPIX power distribution system. Tests are performed using the PSI46 pixel readout chips on a forward pixel panel module and the DC-DC converters developed at CERN and Fermilab. Reliability studies include the voltage drop measurements on the readout chips and the power supply noise generated from the converter. Performance studies include pixel noise and threshold dispersion results. Comparison between step-down only and step-up/step-down conversi...

Todri, A; Rivera, R; Kwan, S; 10.1088/1748-0221/5/12/C12010

2010-01-01

400

Parasitic Effects on the Performance of DC-DC SEPIC in Photovoltaic Maximum Power Point Tracking Applications  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents an analysis of the effect of parasitic resistances on the performance of DC-DC Single Ended Pri- mary Inductor Converter (SEPIC) in photovoltaic maximum power point tracking (MPPT) applications. The energy storage elements incorporated in the SEPIC converter possess parasitic resistances. Although ideal components significantly simplifies model development, but neglecting the parasitic effects in models may sometimes lead to failure in predicting first scale stability and actual performance. Therefore, the effects of parasitics have been taken into consideration for improving the model accuracy, stability, robustness and dynamic performance analysis of the converter. Detail mathematical model of SEPIC converter including inductive parasitic has been developed. The performance of the converter in tracking MPP at different irradiance levels has been analyzed for variation in parasitic resistance. The converter efficiency has been found above 83% for insolation level of 600 W/m2 when the parasitic resistance in the energy storage element has been ignored. However, as the parasitic resistance of both of the inductor has increased to 1 ohm, a fraction of the power managed by the converter has dissipated; as a result the efficiency of the converter has reduced to 78% for the same insolation profile. Although the increasing value of the parasitic has assisted the converter to converge quickly to reach the maximum power point. Furthermore it has also been observed that the peak to peak load current ripple is reduced. The obtained simulation results have validated the competent of the MPPT converter model.

Nur Mohammad; Muhammad Quamruzzaman; Mohammad Rubaiyat Tanvir Hossain; Mohammad Rafiqul Alam

2013-01-01

 
 
 
 
401

Development of Buck-Type Single-Phase to Three-Phase Power Converter with Active Buffer  

Science.gov (United States)

This paper proposes a novel single-phase to three-phase power converter that can reduce the capacitance value of the smoothing capacitor in the DC link part. In the case of the single-phase converter, a large smoothing capacitor is required to absorb a power ripple with a frequency twice that of the power supply. The proposed method involves the use of an indirect matrix converter with an active snubber to absorb the power ripple. Therefore, the proposed system does not require a reactor and large energy buffer, such as a smoothing capacitor. Moreover, a diode bridge can be used on the rectifier stage in the proposed circuit. In this paper, the basic operation and validity of the proposed method are confirmed by simulation and experiment result. Thus, it is confirmed that good waveforms for input and output currents can be obtained by the proposed method.

Ohnuma, Yoshiya; Itoh, Jun-Ichi

402

Control IC for a 6-channel switching DC-DC converter compatible with synchronous rectifiers; Doki seiryu taio 6 channel DC-DC converter seigyo IC  

Energy Technology Data Exchange (ETDEWEB)

Portable electronic appliances such as video cameras require small size, light weight and long operation with batteries. To meet these requirements, power supply systems for these appliances are required to be small and light, of low current consumption and of high efficiency Fuji Electric has developed a control IC for 6-channel switching power supply suitable for multiple output configuration and partly compatible with synchronous rectifier systems to improve power supply efficiency. This paper describes the ratings, features and application examples of this control IC. (author)

Endo, K. [Fuji Electric Co. Ltd., Tokyo (Japan)

2000-08-10

403

Start-stop and recuperation: DC/DC current inverters with integrated double-layer condensers; Start-Stopp und Rekuperation: DC/DC-Wandler mit integrierten Doppelschichtkondensatoren  

Energy Technology Data Exchange (ETDEWEB)

Start-stop systems may be made more efficient, and energy recovery in regenerative brakes may be made more economical. The contribution describes a new DC/DC current inverter with integrated double-layer condensers developed by the electric/electronics department of Alcoa. The so-called Energy Conversion Module (ECM) will result in considerable fuel savings and also help to stabilize board grids which are nearing their limits because of the increasing number of electrified service aggregates. Motor car producers are currently testing the module. (orig.)

Igel, Juergen; Ollhaeuser, Helmut; Jeuck, Marc; Apfelbacher, Thomas [Alcoa/AFL Europe GmbH, Frickenhausen (Germany)

2008-09-15

404

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

405

Resonant power converters  

CERN Multimedia

This book is devoted to resonant energy conversion in power electronics. It is a practical, systematic guide to the analysis and design of various dc-dc resonant inverters, high-frequency rectifiers, and dc-dc resonant converters that are building blocks of many of today's high-frequency energy processors. Designed to function as both a superior senior-to-graduate level textbook for electrical engineering courses and a valuable professional reference for practicing engineers, it provides students and engineers with a solid grasp of existing high-frequency technology, while acquainting them wit

Kazimierczuk, Marian K

2012-01-01

406

Topological constraints on basic PWM converters  

Science.gov (United States)

A modeling and synthesis technique is introduced for single-ended ladder-structured dc-dc converter topologies. Topological constraints are derived that enhance the understanding of structural properties of converter circuits and clarify the roles of inductors and capacitors in various converters using magnetic or capacitive energy storage/transfer mechanisms. The exact duality relationships among the basic converter topologies are established.

Liu, Kwang-Hwa; Lee, Fred C.

407

A Comprehensive Power Analysis and a Highly Efficient, Mode-Hopping DC-DC Converter  

UK PubMed Central (United Kingdom)

A comprehensive power analysis, keeping integratedcircuits in mind, is presented while highlighting allconduction, switching, and dynamic power losses in a DC-DCconverter. Synchronous rectification, zero-voltage switching,mode-hopping, and variable frequency operation areevaluated. The efficiency for constant frequency CCM,constant frequency DCM, and constant on-time, variablefrequency DCM techniques is analyzed and the optimumtechnique is derived. It is concluded that a mode-hoppingconverter employing an asynchronous, constant on-time,variable frequency DCM operation for low output currentsand a synchronous, constant frequency CCM operation forhigh load currents yields the best efficiency performance.

Mark Gildersleeve; Hassan Pooya Forghani-zadeh; Student Member; Gabriel A. Rincn-mora; Senior Member

408

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; Ivan Feno; Gabriel Kacor

2004-01-01

409

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; S. Arulmozhi; V. Kamaraj

2009-01-01

410

Design, Manufacturing and characterization of integrated inductors with magnetic layers for DC-DC converter  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents the conception, fabrication and characterization of integrated inductors containing magnetic layers. We require different steps of micro-technologies: preparation of glass and ferrite substrates, RF sputtering, photolithography, etching and finally electroplating techniques for copper and gold films. The geometrical magnitudes are determined by using HFSS simulator software. The measurements performed at low and high frequencies (up to 1 GHz) permit to verify the correlation between experiment and simulation results. The inductance of the manufactured spiral inductor is ??about 200 nH and it is constant from low frequency up to 0.9 GHz.

Ali Siblini

2012-01-01

411

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

412

Arranque suave para un motor de CD a través de un convertidor reductor CD-CD/ Smooth Starter for a DC Machine through a DC-to-DC Buck Converter  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish En este artículo se presenta el diseño e implementación de un controlador de velocidad para un motor de CD a través de un convertidor reductor, el cual sigue una trayectoria de referencia suave diseñada mediante un polinomio de interpolación Bézier. El sistema reduce los picos súbitos de voltaje y corriente en el circuito de armadura del motor durante el arranque. El cálculo del control de velocidad se obtiene de una salida F llamada salida plana (calculada a tra (more) vés de la matriz de controlabilidad de Kalman). Este control se basa en la retroalimentación de todos los estados reescritos en términos de la salida plana y de sus derivadas sucesivas para el seguimiento de la trayectoria. Con la ayuda de la técnica de ubicación de polos es posible sintonizar adecuadamente el controlador en lazo cerrado. La efectividad del sistema se verifica experimentalmente mediante una plataforma que está compuesta por el convertidor reductor-motor CD y un modulador PWM. Abstract in english This article presents the design and implementation of a speed controller for a DC motor through a buck converter, which tracks a smooth reference trajectory designed by a Bezier polynomial interpolation. The system reduces voltage and current sudden peaks in the armature circuit of the motor during the start. The calculation of the speed control is obtained from an output F called flat output (calculated through the Kalman controllability matrix). This control is based o (more) n feedback from all states rewritten in terms of the flat output and its successive derivatives for tracking the trajectory. With the aid of the pole placement technique it is possible to properly tune the controller in closed loop. The effectiveness of the system is verified experimentally by means of a platform that consists of the DC motor-buck converter and a PWM modulator.

Linares-Flores, J; Antonio-García, A; Orantes-Molina, A

2011-06-01

413

An Integrated Onboard Charger and Accessary Power Converter for Plug-in Electric Vehicles  

Energy Technology Data Exchange (ETDEWEB)

Abstract: In this paper, an integrated onboard battery charger and accessary dc-dc converter for plug-in electric vehicles (PEVs) is presented. The idea is to utilize the already available traction drive inverters and motors of a PEV as the frond converter of the charger circuit and the transformer of the 14 V accessary dc-dc converter to provide galvanic isolation. The topology was verified by modeling and experimental results on a 5 kW charger prototype

Su, Gui-Jia [ORNL; Tang, Lixin [ORNL

2013-01-01

414

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

Directory of Open Access Journals (Sweden)

Full Text Available 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

415

Bidirectional converter interface for a battery energy storage test bench  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 rat...

Trintis, Ionut; Thomas, Stephan; Blank, Tobias; Roggendorf, Christoph; Munk-Nielsen, Stig; Teodorescu, Remus

416

Measurements and Modeling of Conducted EMI in a Buck Chopper  

International Nuclear Information System (INIS)

The high increase of power electronic devices use (speed control, lighting, heating, automotive, etc...) requires the electrical, thermal and electromagnetic behavior studies. In this paper we developed a model to predict the conducted EMI level in a DC/DC converter. Measurement methodology was done using a network analyzer in order to evaluate the equivalent impedance model of each converter element. The full circuit model is then implemented in the Saber-trademark simulation tool using time domain simulation followed by fast Fourier transformation (FFT) in the frequency range 150 KHz -100 MHz. A comparison between simulation results and those obtained by measurements is used to validate the developed model. (author)

2011-01-01

417

A new soft switched push pull current fed converter for fuel cell applications  

International Nuclear Information System (INIS)

In this paper a new zero voltage switching current fed push pull dc-dc converter is proposed for fuel cell generation system. The auxiliary circuit in this converter, not only absorbs the voltage surge across the switches at turn off instance, but also provides zero voltage switching condition for all converter switches. Therefore, the converter efficiency is increased and size and weight of the converter can be decreased. Also implementation of control circuit is very simple since the converter is PWM controlled. In this paper, the proposed dc-dc converter operating modes are analyzed and to verify the converter operation a laboratory prototype is implemented and the experimental results are presented.