Design of the DC-DC power stage of the capacitor charger for MAXIDISCAP power converters
Cravero, Jean-Marc
2013-01-01
This technical report presents the design of the DC-DC power stage of the capacitor charger for MAXIDISCAP power converters. The power stage is based on a half bridge series resonant converter in Discontinuous Conduction Mode (DCM). This simple and robust topology allows obtaining a current source behavior with a low switching losses power stage. The associated control stage is implemented using a commercial controller which has differenti nternal circuits that allows a high integration of the converter control system. The report presents the design and tuning criteria for the DC-DC converter, including the power stage and the control system.
Regulation of a lightweight high efficiency capacitor diode voltage multiplier dc-dc converter
Harrigill, W. T., Jr.; Myers, I. T.
1976-01-01
A method for the regulation of a capacitor diode voltage multiplier dc-dc converter has been developed which has only minor penalties in weight and efficiency. An auxiliary inductor is used, which only handles a fraction of the total power, to control the output voltage through a pulse width modulation method in a buck boost circuit.
Multiple output zero-current switching switched-capacitor bidirectional dc-dc converter
Lee, Yuang-Shung; Ko, Yi-Pin; Chi, Chien-An
2010-08-01
The proposed circuit is a multiple output quasi-resonant (QR) zero-current switching (ZCS) switched-capacitor (SC) converter with a bidirectional power flow control conversion scheme. The principles of the proposed multiple output QR ZCS SC bidirectional dc-dc converter are described using a detailed circuit model for analysis. Simulation and experimental results are carried out to verify the validity and the soft switching performance of the proposed converter. The maximum efficiency achievable is about 94 and 92% for the forward and reverse power flow control schemes, respectively. The output voltage can be regulated by changing the switching frequency for the designed compensated closed-loop controller.
Switched capacitor DC-DC converter ASICs for the upgraded LHC trackers
Energy Technology Data Exchange (ETDEWEB)
Bochenek, M; Faccio, F; Michelis, S [CERN, CH-1211 Geneve 23 (Switzerland); Dabrowski, W, E-mail: Michal.Bochenek@cern.ch [AGH University of Science and Technology, Faculty of Physics and Applied Computer Science, Al. Mickiewicza 30 30-059 Krakow (Poland)
2010-12-15
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.
Switched capacitor DC-DC converter ASICs for the upgraded LHC trackers
Bochenek, M; Faccio, F; Michelis, S
2010-01-01
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
Design and implementation of a switched capacitor-based embedded hybrid DC-DC converter
Bhattacharyya, Kaushik; Mandal, Pradip
2012-06-01
Here, we propose an integrated hybrid DC-DC converter suitable for high drop-out energy conscious applications. In the hybrid converter topology, along with a linear regulator two switched capacitors are used to store and recycle charge for better power efficiency. Without significant power loss the switched capacitors step down the supply voltage for the linear regulator working in low drop-out mode. The linear regulator, on the other hand, attenuates the voltage ripple that originates from the switched capacitors converter on its power supply rejection ratio. It also helps for line and load regulation. Additionally, a synthesised counter ripple is injected through the linear regulator to further reduce the output ripple. With these two techniques, for a moderate load current and an acceptable output ripple, the switching and load capacitors are reduced to a value which can be implemented within the chip. The proposed integrated converter circuit has been designed, implemented and tested in a 0.18 mm CMOS process for 3.3-1.3V conversion. With two switching capacitors of 210 pF each and 100 pF load capacitor, more than 13 mA of load current, measured peak-to-peak output voltage ripple is 146 mV. The achieved measured power efficiency is 64.97%. Exhaustive silicon characterisation of the converter is done to observe the power efficiency and ripple variation at different frequency of operations.
A Monolithically Integrated 12V/5V Switch-Capacitor DC-DC Converter
Institute of Scientific and Technical Information of China (English)
耿莉; 陈治明; 刘先锋
2000-01-01
A monolithically integrated 12V/SV switch capacitor DC-DC converter with structure-simplified main circuit and control circuit is presented. Its topological circuit and basic operating principle are discussed in detail. It is shown that elevated operating frequency, increased capacitance and reduced turn-on voltage of the diodes can make the converter's output characteristics improved. Reducing resistance of the equivalent resistors and other parasitic parameters can make the operation frequency higher. As a feasible efficient method to fabricate monolithically integrated converter with high frequency and high output power, several basic circuits are parallelly combined where the serial-parallel capacitance is optimized for the maximum output power. The device selection and its fabrication method are presented. A feasible integration process and its corresponding layout are designed. All active devices including switching transistors and diodes are integrated together with all passive cells including capacitors and resistor on a single chip based on BiMOS process,as has been verified to be correct and practical by simulation and chip test.
Wide-range 7-switch flying capacitor based dc-dc converter for point-of-load applications
Jain, Parth
In this thesis a dc-dc converter referred to as the 7-switch flying capacitor (7SFC) based multi-level buck converter intended for point-of-load applications is presented. The 7SFC operates with the principle of "transformability" which allows it to run in several switching modes when paired with a digital controller. The mode is selected based on input and output conditions by estimating the highest efficiency mode. The 7SFC converter utilizes a flying capacitor, which for certain modes allows for a large reduction in switching losses, especially when the converter is operated with high-input voltages. Compared to the conventional 2-phase interleaved buck converter, the 7SFC is able to reduce the size of the output inductors and capacitor by 33%. The 7SFC discrete prototype is able to achieve efficiencies greater than 90% over the majority of the operating range.
Charge pump DC-DC converter comprising solid state batteries
Reefman, D.; Roozeboom, F.; Notten, P.H.L.; Klootwijk, J.H.
2013-01-01
An electronic device is provided which comprises a DC-DC converter. The DC-DC converter comprises at least one solid-state rechargeable battery (B1, B2) for storing energy for the DC-DC conversion and an output capacitor (C2).
Luo, Fang Lin
2003-01-01
INTRODUCTIONHistorical ReviewMultiple Quadrant ChoppersPump CircuitsDevelopment of DC/DC Conversion TechniqueCategorize Prototypes and DC/DC Converters Family TreeVOLTAGE-LIFT CONVERTERSIntroductionSeven Self-Lift ConvertersPositive Output Luo-ConvertersNegative Output Luo-ConvertersModified Positive Output Luo-Converters Double Output Luo-ConvertersPOSITIVE OUTPUT SUPER-LIFT LUO-CONVERTERS IntroductionMain SeriesAdditional SeriesEnhanced Series Re-Enhanced Series Multiple-Enhanced Series Summary of Positive Output
National Aeronautics and Space Administration — Studying and analyzing the ageing mechanisms of electronic components avionics in systems such as the GPS and INAV are of critical importance. In DC-DC power...
DEFF Research Database (Denmark)
Schaltz, Erik; Li, Zhihao; Onar, Omer;
2009-01-01
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 con......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...
Chen, Juan
2008-01-01
This report is the result of a Master Thesis work done at Seaward Electronics Inc. in Beijing, China from June to December in 2007. The main goal for this thesis is to verify and improve the performance of Honey-PWM DC-DC converter, which has been fabricated by a standard 0.6um CMOS processes. The project was started with studying of Buck converter structure. After the understanding of the converter structure, the project goes in to the analyses phase for each sub-cells, including the theory,...
High-Efficiency Self-Adjusting Switched Capacitor DC-DC Converter with Binary Resolution
Kushnerov, Alexander
2010-01-01
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 work by developing two new classes of SCC providing binary and arbitrary resolution of closely spaced target voltages. Special attention is paid to SCC topologies of binary resolution. Namely, SCC systems that can be configured to have a no-load output to input voltage ratio that is equal to any binary fraction for a given number of bits. To this end, we define a new number system and develop rules to translate these numbers into SCC hardware that follows the algebraic behavior. According to this approach, the flying capacitors are automatically kept charged to binary weighted voltages and consequently the resolution of the target voltages follows a binary number representation and can be made higher by increasing t...
Energy Technology Data Exchange (ETDEWEB)
Hao Wenhan; Jia Chen; Chen Hong; Zhang Chun; Wang Zhihua, E-mail: haowh04@mails.tsinghua.edu.c [Tsinghua National Laboratory for Information Science and Technology, Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)
2009-12-15
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)
Physics of Failure Models for Capacitor Degradation in DC-DC Converters
National Aeronautics and Space Administration — This paper proposes a combined energy-based model with an empirical physics of failure model for degradation analysis and prognosis of electrolytic capacitors in...
High frequency capacitor-diode voltage multiplier dc-dc converter development
Kisch, J. J.; Martinelli, R. M.
1977-01-01
A power conditioner was developed which used a capacitor diode voltage multiplier to provide a high voltage without the use of a step-up transformer. The power conditioner delivered 1200 Vdc at 100 watts and was operated from a 120 Vdc line. The efficiency was in excess of 90 percent. The component weight was 197 grams. A modified boost-add circuit was used for the regulation. A short circuit protection circuit was used which turns off the drive circuit upon a fault condition, and recovers within 5 ms after removal of the short. High energy density polysulfone capacitors and high speed diodes were used in the multiplier circuit.
A fully on-chip three-terminal switched-capacitor DC-DC converter for low-voltage CMOS LSIs
Kojima, Yuta; Hirose, Tetsuya; Tsubaki, Keishi; Ozaki, Toshihiro; Asano, Hiroki; Kuroki, Nobutaka; Numa, Masahiro
2016-04-01
In this paper, we present a fully on-chip switched-capacitor DC-DC converter for low-voltage CMOS LSIs. The converter has three terminals of input, ground, and output, by developing control circuits with fully on-chip configuration. We employ an ultra low-power nanoampere bias current and voltage reference circuit to achieve ultra low-power dissipation of control circuits. It enables us to realize a highly efficient power conversion circuit at light-load-current applications. The converter achieves highly efficient and robust voltage conversion using a pulse frequency modulation control circuit and a start-up/fail-safe circuit. Measurement results demonstrated that the converter can convert a 3.0 V input into 1.2 V output successfully. The start-up and fail-safe operations were confirmed through the measurement. The efficiency was more than 50% in the range of 2-6 µA load current.
DEFF Research Database (Denmark)
2015-01-01
The present invention relates to a step-up DC-DC power converter which comprises a primary side circuit and a secondary side circuit coupled through a galvanic isolation barrier. The primary side circuit comprises a positive and a negative input terminal for receipt of an input voltage and an input...... being charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier in accordance with a switch control signal to produce the converter output voltage. The step-up DC-DC power converter comprises an electrical short-circuit connection across the galvanic...
CMOS Integrated Capacitive DC-DC Converters
Van Breussegem, Tom
2013-01-01
This book provides a detailed analysis of all aspects of capacitive DC-DC converter design: topology selection, control loop design and noise mitigation. Readers will benefit from the authors’ systematic overview that starts from the ground up, in-depth circuit analysis and a thorough review of recently proposed techniques and design methodologies. Not only design techniques are discussed, but also implementation in CMOS is shown, by pinpointing the technological opportunities of CMOS and demonstrating the implementation based on four state-of-the-art prototypes. Provides a detailed analysis of all aspects of capacitive DC-DC converter design; Analyzes the potential of this type of DC-DC converter and introduces a number of techniques to unleash their full potential; Combines system theory with practical implementation techniques; Includes unique analysis of CMOS technology for this application; Provides in-depth analysis of four fabricated prototypes.
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
A Family of Four Quadrant DC/DC Converters with Reduced Number of Components
DEFF Research Database (Denmark)
Mostaan, Ali; Soltani, Mohsen
2016-01-01
A family of four quadrant DC/DC converters is presented in this paper. Compare with existing four quadrant DC/DC converters that have been introduced in literature, the proposed converters have lower number of components. There are two bidirectional switches, two coupled inductors and one capacitor...
A Multiport Isolated DC-DC Converter
Tran, Yan-Kim; Dujic, Drazen
2016-01-01
This paper presents a multi-port isolated DC-DC converter for DC applications. A three-port structure is presented, characterized with full bidirectional power flow and simple control. Galvanic isolation is achieved by means of a multi-winding medium frequency transformer which is a part of a resonant LLC converter. To provide controllable power exchange with external DC ports, two out of three ports are equipped with additional bidirectional buck/boost stages. They serve to provide active po...
A resonant dc-dc power converter assembly
DEFF Research Database (Denmark)
2015-01-01
The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor...... of the second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or forcing substantially 0 degree phase shift, between corresponding resonant voltage waveforms of the first...... and second resonant DC-DC power converters. The first and second inductors are corresponding components of the first and second resonant DC-DC power converters....
Multiport Resonant DC-DC Converter
Tran, Yan-Kim; Dujic, Drazen; Barrade, Philippe
2015-01-01
his paper presents a multiport galvanically isolated LLC resonant DC-DC converter suitable for DC applications. A three-port structure is analyzed, with full bidirectional power flow capabilities, simple control and behavior similar to that expected from a DC transformer. Each port is equipped with half-bridge modules accompanied with tuned resonant tank, partly realized with elements of a multi- winding high frequency transformer. With some restrictions that are explained in the paper, each ...
RESONANT STEP-DOWN DC-DC POWER CONVERTERS
DEFF Research Database (Denmark)
2015-01-01
charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier by a semiconductor switch arrangement in accordance with a switch control signal to produce the converter output voltage. The resonant step-down DC-DC power converter comprises an electrical short...... of the primary side circuit thereby establishing in both the first and second cases a series coupling of the output capacitor and the input capacitor. A load connection is established, in the first case, between the first positive electrode of the output capacitor and the positive input terminal or......-circuit connection across the galvanic isolation barrier connecting, in a first case, the second negative electrode of the output capacitor to the positive input terminal of the primary side circuit or, in a second case, connecting the second positive electrode of the output capacitor to the negative input terminal...
Radiation Effects on DC-DC Converters
Zhang, De-Xin; AbdulMazid, M. D.; Attia, John O.; Kankam, Mark D. (Technical Monitor)
2001-01-01
In this work, several DC-DC converters were designed and built. The converters are Buck Buck-Boost, Cuk, Flyback, and full-bridge zero-voltage switched. The total ionizing dose radiation and single event effects on the converters were investigated. The experimental results for the TID effects tests show that the voltages of the Buck Buck-Boost, Cuk, and Flyback converters increase as total dose increased when using power MOSFET IRF250 as a switching transistor. The change in output voltage with total dose is highest for the Buck converter and the lowest for Flyback converter. The trend of increase in output voltages with total dose in the present work agrees with those of the literature. The trends of the experimental results also agree with those obtained from PSPICE simulation. For the full-bridge zero-voltage switch converter, it was observed that the dc-dc converter with IRF250 power MOSFET did not show a significant change of output voltage with total dose. In addition, for the dc-dc converter with FSF254R4 radiation-hardened power MOSFET, the output voltage did not change significantly with total dose. The experimental results were confirmed by PSPICE simulation that showed that FB-ZVS converter with IRF250 power MOSFET's was not affected with the increase in total ionizing dose. Single Event Effects (SEE) radiation tests were performed on FB-ZVS converters. It was observed that the FB-ZVS converter with the IRF250 power MOSFET, when the device was irradiated with Krypton ion with ion-energy of 150 MeV and LET of 41.3 MeV-square cm/mg, the output voltage increased with the increase in fluence. However, for Krypton with ion-energy of 600 MeV and LET of 33.65 MeV-square cm/mg, and two out of four transistors of the converter were permanently damaged. The dc-dc converter with FSF254R4 radiation hardened power MOSFET's did not show significant change at the output voltage with fluence while being irradiated by Krypton with ion energy of 1.20 GeV and LET of 25
Radiation-Tolerant DC-DC Converters
Skutt, Glenn; Sable, Dan; Leslie, Leonard; Graham, Shawn
2012-01-01
A document discusses power converters suitable for space use that meet the DSCC MIL-PRF-38534 Appendix G radiation hardness level P classification. A method for qualifying commercially produced electronic parts for DC-DC converters per the Defense Supply Center Columbus (DSCC) radiation hardened assurance requirements was developed. Development and compliance testing of standard hybrid converters suitable for space use were completed for missions with total dose radiation requirements of up to 30 kRad. This innovation provides the same overall performance as standard hybrid converters, but includes assurance of radiation- tolerant design through components and design compliance testing. This availability of design-certified radiation-tolerant converters can significantly reduce total cost and delivery time for power converters for space applications that fit the appropriate DSCC classification (30 kRad).
Directory of Open Access Journals (Sweden)
Mohamed Daowd
2014-04-01
Full Text Available Lithium-based batteries are considered as the most advanced batteries technology, which can be designed for high energy or high power storage systems. However, the battery cells are never fully identical due to the fabrication process, surrounding environment factors and differences between the cells tend to grow if no measures are taken. In order to have a high performance battery system, the battery cells should be continuously balanced for maintain the variation between the cells as small as possible. Without an appropriate balancing system, the individual cell voltages will differ over time and battery system capacity will decrease quickly. These issues will limit the electric range of the electric vehicle (EV and some cells will undergo higher stress, whereby the cycle life of these cells will be shorter. Quite a lot of cell balancing/equalization topologies have been previously proposed. These balancing topologies can be categorized into passive and active balancing. Active topologies are categorized according to the active element used for storing the energy such as capacitor and/or inductive component as well as controlling switches or converters. This paper proposes an intelligent battery management system (BMS including a battery pack charging and discharging control with a battery pack thermal management system. The BMS user input/output interfacing. The battery balancing system is based on battery pack modularization architecture. The proposed modularized balancing system has different equalization systems that operate inside and outside the modules. Innovative single switched capacitor (SSC control strategy is proposed to balance between the battery cells in the module (inside module balancing, IMB. Novel utilization of isolated bidirectional DC/DC converter (IBC is proposed to balance between the modules with the aid of the EV auxiliary battery (AB. Finally an experimental step-up has been implemented for the validation of the
Digital Control Technologies for Modular DC-DC Converters
Button, Robert M.; Kascak, Peter E.; Lebron-Velilla, Ramon
2002-01-01
Recent trends in aerospace Power Management and Distribution (PMAD) systems focus on using commercial off-the-shelf (COTS) components as standard building blocks. This move to more modular designs has been driven by a desire to reduce costs and development times, but is also due to the impressive power density and efficiency numbers achieved by today's commercial DC-DC converters. However, the PMAD designer quickly learns of the hidden "costs" of using COTS converters. The most significant cost is the required addition of external input filters to meet strict electromagnetic interference (MIAMI) requirements for space systems. In fact, the high power density numbers achieved by the commercial manufacturers are greatly due to the lack of necessary input filters included in the COTS module. The NASA Glenn Research Center is currently pursuing a digital control technology that addresses this problem with modular DC-DC converters. This paper presents the digital control technologies that have been developed to greatly reduce the input filter requirements for paralleled, modular DC-DC converters. Initial test result show that the input filter's inductor size was reduced by 75 percent, and the capacitor size was reduced by 94 percent while maintaining the same power quality specifications.
DEFF Research Database (Denmark)
Zhang, Zhe; Ouyang, Ziwei; Thomsen, Ole Cornelius;
2012-01-01
of the proposed converter, the ZVS conditions and the quasi-optimal design in depth. The design guidelines and considerations about the transformers and other key components are given. Finally, a 1- kW 30~50-V-input 400-V-output laboratory prototype operating at 100 kHz switching frequency is built and tested...... transformers which combine a half-bridge circuit and a full-bridge circuit together on the primary side. The voltage doubler circuit is employed on the secondary side. The current-fed input can limit the input current ripple that is favorable for fuel cells. The parasitic capacitance of the switches is used...... for zero voltage switching (ZVS). Moreover, a phase-shift and duty cycle modulation method is utilized to control the bidirectional power flow flexibly and it also makes the converter operate under a quasi-optimal condition over a wide input voltage range. This paper describes the operation principle...
DEFF Research Database (Denmark)
Mostaan, Ali; Alizadeh, Ebrahim; Soltani, Mohsen
2014-01-01
Novel step-up DC/DC converter is introduced in this paper. This converter is realized with adding the switched capacitor voltage multiplier cell to the three switch step-down DC/DC converter that has been proposed in the literature. The proposed converter is analyzed in the steady state...
Intelligent dc-dc Converter Technology Developed and Tested
Button, Robert M.
2001-01-01
The NASA Glenn Research Center and the Cleveland State University have developed a digitally controlled dc-dc converter to research the benefits of flexible, digital control on power electronics and systems. Initial research and testing has shown that conventional dc-dc converters can benefit from improved performance by using digital-signal processors and nonlinear control algorithms.
Design and Implementation of Digital Current Mode Controller for DC-DC Converters
DEFF Research Database (Denmark)
Taeed, Fazel
In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required to be regula......In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required...... to be regulated by a closed-loop controller. The Peak Current Mode Control (PCMC) is one of the most promising control methods for dc-dc converters. It has been known for high bandwidth (speed), and inherent current protection. Increasing the controller bandwidth decreases the output filter size and cost. Analog....... Analyzing the obtained model reveals that the small values of capacitor and inductor ESR results in a large resonance peak of complex poles in the voltage to duty cycle transfer function. High efficiency dc-dc converters essentially have low ESR in the capacitor and the inductor. Since the complex poles...
DEFF Research Database (Denmark)
Pelan, Ovidiu; Cornea, Octavian; Muntean, Nicolae;
2014-01-01
This paper presents and discusses design considerations and efficiency investigation of a conventional step-down and a hybrid switched-capacitor DC-DC converter. Three MOSFETs with low on-resistance have been tested for each converter in order to find the most adequate switch for this application...
Mono-switch AC-DC/DC-DC converter for single-phase UPS%单相UPS的单开关AC-DC/DC-DC变换电路
Institute of Scientific and Technical Information of China (English)
李宋; 叶满园; 袁义生
2011-01-01
A mono-switch AC-DC/DC-DC converter used in single-phase UPS system is introduced,which consists of one power switch and six diodes. As both AC-DC rectifier and DC-DC booster,its operating modes and working principle are detailed. The single-cycle nonlinear control is adopted,which applies two low-speed PI regulators to control the voltage of two capacitors on DC link and a high-speed PI regulator to control the input current. Simulative results prove that,being simple and reliable,it outputs stable DC bus voltage with high input power factor and low THD.%介绍了一种应用在单相UPS系统中的新型单开关AC-DC/DC-DC变换电路,该电路由1个功率开关器件和6个二极管组成,能够实现AC/DC整流和DC/DC升压2种功能.在详细分析了该电路运行模式及工作原理的基础上,采用了单周期非线性控制理论对其进行控制,利于2个低速PI调节器对直流母线上的2个电容器电压进行控制,1个高速PI调节器对输入电流进行控制.仿真结果表明,该电路简单可靠,输入功率因数高,电流谐波失真小,可以获得稳定的正负直流母线电压.
Five-Level Active-Neutral-Point-Clamped DC/DC Converter for Medium Voltage DC Grids
DEFF Research Database (Denmark)
Liu, Dong; Deng, Fujin; Chen, Zhe
2016-01-01
This paper proposes a five-level active-neutralpoint- clamped (5L-ANPC) dc/dc converter for applications in medium voltage dc (MVDC) grids. A modulation strategy is proposed for the 5L-ANPC dc/dc converter to generate multilevel voltage waveforms, which can effectively reduce voltage change rate dv...... effectively eliminate high voltage leaps caused by the dead time effect. In addition, a capacitor voltage control strategy is proposed for the 5L-ANPC dc/dc converter to ensure the balanced flying capacitor voltage and desired five-level voltage waveforms. Finally, simulation and experimental studies...
A Bidirectional Multi-Port DC-DC Converter Integrating Voltage Equalizer
DEFF Research Database (Denmark)
Chen, Jianfei; Hou, Shiying; Deng, Fujin;
2015-01-01
A novel bidirectional multi-port dc-dc converter integrating voltage equalizer based on switched-capacitor voltage accumulator (SCVA) is proposed. It has two operating modes of charging and discharging for battery modules. All battery modules are connected in series indirectly and can be equalized...... with a uniform voltage level while eliminating the voltage imbalance. In addition, high step-down and step-up ratios with low component voltage stress can be achieved in the proposed converter. A bidirectional four-port dc-dc converter is presented to do theoretical analysis for the voltage equalization of three...
Simulation and Implementation of Quasi Resonant DC-DC Converter
Directory of Open Access Journals (Sweden)
N. Devarajan
2012-01-01
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.
Regulation of a lightweight high efficiency capacitator diode voltage multiplier dc-dc converter
Harrigill, W. T., Jr.; Myers, I. T.
1976-01-01
A method for the regulation of a capacitor diode voltage multiplier dc-dc converter has been developed which has only minor penalties in weight and efficiency. An auxiliary inductor is used, which only handles a fraction of the total power, to control the output voltage through a pulse width modulation method in a buck boost circuit.
On and off controlled resonant dc-dc power converter
DEFF Research Database (Denmark)
2015-01-01
output voltage and connection to a converter load. The resonant DC-DC power converter further comprises a rectification circuit connected between an output of a resonant network and the output side circuit. The resonant network is configured for alternatingly being charged from the input voltage...... or current and discharged through the rectification circuit by a first controllable switch arrangement in accordance with a first switch control signal. A second controllable switch arrangement of the resonant DC-DC power converter is configured to select a first impedance characteristic of the resonant...
Custom DC-DC converters for distributing power in SLHC trackers
Allongue, B; Blanchot, G; Faccio, F; Fuentes, C; Mattavelli, P; Michelis, S; Orlandis, S; Spiazzi, G
2008-01-01
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.
Harrigill, W. T., Jr.; Myers, I. T.
1974-01-01
An experimental 100W 1000V dc-dc converter using a capacitor diode voltage multipler (CDVM) with a nominal frequency of 100 kHz is studied. A component weight of about 1 kg/kW was obtained. Design equations for current, output -ripple and -power, efficiency and output voltage are derived. Agreement between experimental results and calculations is fairly good except for ripple.
Very High Frequency Half Bridge DC/DC Converter
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
2014-01-01
This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...
A Novel FPSM Controller for DC-DC Switching Converters
Institute of Scientific and Technical Information of China (English)
Yong Feng; Shun-Ping Wang; Ping Luo; Quan-Ming Niu; Zhao-Ji Li
2007-01-01
This paper presents a novel fuzzy pulse skip modulation (FPSM) controller for switching direct current to direct current (DC-DC) converters based on fuzzy ratiocination modeling approach. Owing to the optimal consideration during the design and the nonlinear characteristics of the controller, improved dynamic responses of the FPSM controller can be achieved over conventional controllers. Compared with conventional proportion integral derivative (PID) control, FPSM control has 60% lower overshoot and 10% lower setting time under the same input voltage and output load change. The presented approach is general and can be applied to other types of DC-DC converters.
Energy Technology Data Exchange (ETDEWEB)
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
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)
Efficient, lightweight dc/dc switching converter
Cuk, S.; Middlebrook, R. D.
1981-01-01
Converters have input properties of boost power stage and output properties of buck power stage, yet they perform general conversion function with high efficiency. Other features include non-pulsating input/output currents, use of capacitive energy transfer, low output voltage ripple, reduced EMI, and small size.
A Novel High Gain DC-DC Step up Converter
Directory of Open Access Journals (Sweden)
M. Al Mamun
2016-07-01
Full Text Available High gain dc-dc converters are widely used to maximize the energy harvest for renewable energy systems, for example, photovoltaic systems and fuel cell. Conventional boost converters usually operates at extreme duty cycle to obtain high voltage gain. Operation at extreme duty cycle leads to reverse recovery problem at the switches, high conduction loss, electromagnetic interference etc. This paper proposes a very high gain dc-dc step up converter operating at very low duty cycle (i.e. duty cycle <0.5. The additional advantage of the proposed converter is that a single control signal is used for the switches which reduces the operation complexity. The steady-state theoretical analysis described in this paper is finally verified by simulation results
Hybrid battery with bi-directional DC/DC converter
Directory of Open Access Journals (Sweden)
DUDRIK Jaroslav
2010-05-01
Full Text Available Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.
Hybrid battery with bi-directional DC/DC converter
DUDRIK Jaroslav; OLEJAR Martin; BERES Tomáš
2010-01-01
Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.
Radiated electromagnetic emissions of DC-DC converters
Sammet, Jan Domenik
2010-01-01
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.
Hybrid posicast controller for a DC-DC buck converter
Kaithamalai Udhayakumar; Ponnusamy Lakshmi; Kandasamy Boobal
2008-01-01
A new Posicast compensated hybrid controller for the DC-DC Buck converter is investigated. Posicast is a feed forward compensator, which eliminates the overshoot in the step response of a lightly damped system. However, the traditional method is sensitive to variations in natural frequency. The new method described here reduces this undesirable sensitivity by using Posicast within the feedback loop. Design of the Posicast function is independent of computational delay. The new controller resu...
Modeling and Analysis of Transformerless High Gain Buck-boost DC-DC Converters
Directory of Open Access Journals (Sweden)
Vu Tran
2014-12-01
Full Text Available This paper proposes a transfomerless switched capacitor buck boost converter model, which provides higher voltage gain and higher efficiency when compared to the conventional buck boost converter. The averaged model based on state-space description is analyzed in the paper. The simulation results are presented to confirm the capability of the converter to generate high voltage ratios. The comparison between the proposed model and the traditional model is also provided to reveal the improvement. The proposed converter is suitable for for a wide application which requires high step-up DC-DC converters such as DC micro-grids and solar electrical energy.
Radiated electromagnetic emissions of DC-DC converters
Energy Technology Data Exchange (ETDEWEB)
Feld, L; Jussen, R; Karpinski, W; Klein, K; Sammet, J; Wlochal, M, E-mail: sammet@cern.ch [Physikalisches Institut IB, RWTH Aachen University, Aachen (Germany)
2010-12-15
For the CMS tracker at SLHC a new powering scheme is considered to be mandatory to allow the detector to provide at least the same performance as today at the LHC. The baseline solution of CMS foresees the use of DC-DC converters to provide larger currents with smaller losses. An important component of most converters are inductors which, however, tend to radiate the switching noise generated by the converter. The emissions of different inductors have been measured and simulated, the coil design has been optimized and noise susceptibility measurements, with present CMS hardware, have been performed. This article summarizes the results.
Embedded Controlled Isolated Bidirectional Full-Bridge DC-DC Converter with Flyback Snubber
Directory of Open Access Journals (Sweden)
D. Kirubakaran
2012-01-01
Full Text Available An isolated bidirectional full-bridge DC-DC converter with flyback snubber for supplying a resistive load is simulated and experimentally verified. The DC-DC converter for high conversion ratio, high output power, and soft start-up capability is presented in this paper. The circuit consists of a capacitor, a diode, and a flyback converter. These components help to clamp the voltage spikes caused by the current difference between the current fed inductor and leakage inductance of the isolation transformer. The switches are operated by soft-switching technology. The suppression of inrush current which is usually found in the boost mode start-up transition is presented here. The simulated and experimental results for output voltage, output current, and power for both buck and boost modes are presented.
Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project
National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex, multiple-output, DC-DC converter systems can be configured through use of only 2 standard product hybrid DC-DC...
Low dose failures of hardened DC-DC power converters
Lehman, J.; Yui, C.; Rax, B. G.; Miyahira, T. F.; Weideman, M.; Schrick, P.; Swift, G. M.; Johnston, A. H.
2002-01-01
Box-level total dose testing of the FOG (Fiber Optic Gyro) by IXSEA at ESA's GammabeamFacility were abruptly terminated at 8krad (Si) due to catastrophic failure (complete shutdown). This was unexpected because all components within the gyro were supposedly radiation tolerant. Further testing showed that the components responsible for the failure were two DC-DC converters, manufactured by Interpoint, that stopped regulating shortly before shutdown. This paper summarizes diagnostic test results for the converters to determine the underlying cause of the unexpected failure at low levels of radiation.
Very High Frequency Half Bridge DC/DC Converter
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
2014-01-01
This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...... components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED...
Modified Multiport Dc-Dc Converter Topology For Smart Grid
Directory of Open Access Journals (Sweden)
Dhamodharan Shanmugam
2013-10-01
Full Text Available The development of a Solid State Transformer (SST that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad active-bridge (QAB converter which not only provides isolation for the load, but also for the PV and storage. The AC-DC stage is implemented with a pulse-widthmodulated (PWM single phase rectifier. A unified gyrator-based average model is developed for a general multi-active-bridge (MAB converter controlled through phase-shift modulation (PSM. Expressions to determine the power rating of the MAB ports are also derived. The developed gyrator-based average model is applied to the QAB converter for faster simulations of the proposed SST during the control design process as well for deriving the state-space representation of the plant. Both linear quadratic regulator (LQR and singleinput-single-output (SISO types of controllers are designed for the DC-DC stage. A novel technique that complements the SISO controller by taking into account the cross coupling characteristics of the QAB converter is also presented herein. Cascaded SISO controllers are designed for the AC-DC stage. The QAB demanded power is calculated at the QAB controls and then fed into the rectifier controls in order to minimize the effect of the interaction between the two SST stages. The dynamic performance of the designed control loops based on the proposed control strategies are verified through extensive simulation of the SST average and switching models.
High voltage conversion ratio, switched C & L cells, step-down DC-DC converter
DEFF Research Database (Denmark)
Pelan, Ovidiu; Muntean, Nicolae; Cornea, Octavian;
2013-01-01
The paper presents a high voltage conversion ratio DC-DC step-down topology obtained from a classical buck converter associated with an input switched-capacitor cell and an output switched-inductor cell. Analytical descriptions, the voltage and current limits of the main components are synthesized...... in a comparative form, related to the classical buck structure, in order to emphasis the advantages of the proposed converter. Digital simulations and experimental results obtained with a built prototype are compared. From the first evaluation, the proposed converter is expected to be effectively used at input...... to output voltage ratios higher than 20....
Hybrid posicast controller for a DC-DC buck converter
Directory of Open Access Journals (Sweden)
Kaithamalai Udhayakumar
2008-01-01
Full Text Available A new Posicast compensated hybrid controller for the DC-DC Buck converter is investigated. Posicast is a feed forward compensator, which eliminates the overshoot in the step response of a lightly damped system. However, the traditional method is sensitive to variations in natural frequency. The new method described here reduces this undesirable sensitivity by using Posicast within the feedback loop. Design of the Posicast function is independent of computational delay. The new controller results in a lower noise in the control signal, when compared to a conventional PID controller.
Bi-Directional DC-DC Converter for PHEV Applications
Energy Technology Data Exchange (ETDEWEB)
Abas Goodarzi
2011-01-31
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.
Hysteretic Current Controlled Zvs Dc/Dc Converter For Automobile
DEFF Research Database (Denmark)
Cernat, M.; Scortarul, P.; Tanase, A.;
2007-01-01
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...
A Novel Dual-input Isolated Current-Fed DC-DC Converter for Renewable Energy System
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;
2010-01-01
In this paper, a novel isolated current-fed DC-DC converter (boost-type) with two input power sources based on multi-transformer structure, which is suitable for fuel cells and super-capacitors hybrid energy system, is proposed and designed. With particular transformer windings connection strategy...
DC/DC converter with improved rectification for higher efficiency
Energy Technology Data Exchange (ETDEWEB)
Maisel, Peter; Saliternig, Martin [Continental AG, Nuernberg (Germany)
2010-07-01
High-power dc-dc converters are an important element of the electrical system of electric vehicles and hybrid electric vehicles. These complex modular components provide the link between the high-voltage level used for the powertrain and the low-voltage bus for the lighting system, engine management and auxiliary needs in the vehicle. The essential requirements for all converters are high efficiency, compact size, lightweight and reliability. A very popular method to increase the efficiency is the synchronous rectification. Parasitic inductances in the commutation circuit and reverse recovery effects can produce a ringing with voltage overshoots at the diodes and the transistors. These spikes can cause higher average power dissipation in the seminconductors and higher EMI (electromagnetic interference).
Exploration of Charge Recycling DC-DC Conversion Using a Switched Capacitor Regulator
Directory of Open Access Journals (Sweden)
Mircea R. Stan
2013-07-01
Full Text Available The increasing popularity of DVFS (dynamic voltage frequency scaling schemes for portable low power applications demands highly efficient on-chip DC-DC converters. The primary aim of this work is to enable increased efficiency of on-chip DC-DC conversion for near-threshold operation of multicore chips. The idea is to supply nominal (high off-chip voltage to the cores which are then “voltage-stacked” to generate the near-threshold (low voltages based on Kirchhoff’s voltage law through charge recycling. However, the effectiveness of this implicit down-conversion is affected by the current imbalance among the cores. The paper presents a design methodology and optimization strategy for highly efficient charge recycling on-chip regulation using a push-pull switched capacitor (SC circuit. A dual-boundary hysteretic feedback control circuit has been designed for stacked loads. A stacked-voltage domain with its self-regulation capability combined with a SC converter has shown average efficiency of 78%–93% for 2:1 down-conversion with ILoad (max of 200 mA and workload imbalance varying from 0–100%.
Sona P; Sheela Joseph
2014-01-01
A high efficiency interleaved ZVS active clamped current fed dc-dc converter is proposed in this paper specially used for fuel cell applications. As the fuel cell output is very low we are in need of a step up dc-dc converter. Here a current fed dc-dc converter is used. Two current fed dc-dc converters are interleaved by connecting their inputs in parallel and outputs in series. With this proposed methodology input current ripples in the fuel cell stacks can be reduced and a re...
A High Voltage-lift Efficient Isolated Full Bridge DC-DC Converter
Directory of Open Access Journals (Sweden)
A. Gopi
2014-05-01
Full Text Available The aim of this study is to propose a high voltage lift isolated full bridge dc-dc converter. The proposed converter consists of an isolation transformer a low turn ratio to obtain high step up voltage gain. The secondary of the transformer connected with two boosting capacitors which connects parallel when power switches switch on period and discharged in series during the switch off period. In addition full bridge converter on primary side consists of clamping diode and capacitor, leakage energy is recycled there by improving conversion efficiency. The proposed circuits simulated using PSIM software form input voltage of 48V, an output of 410 V obtained. These results and operations experimented and validated by implementing in hardware model at 20/40 Vdc, 20 Watts.
A Four-Phase High Voltage Conversion Ratio Bidirectional DC-DC Converter for Battery Applications
Directory of Open Access Journals (Sweden)
Li-Kun Xue
2015-06-01
Full Text Available This study presents a four-phase interleaved high voltage conversion ratio bidirectional DC-DC converter circuit based on coupled inductors and switched capacitors, which can eliminate the defects of conventional high voltage conversion ratio bidirectional DC-DC converters in terms of high-voltage/current stress, less efficiency and low-power limitation. Parallel channels are used to reduce current stress at the low-voltage side and series connected switched capacitors are used to enlarge voltage conversion ratio, reduce voltage stress and achieve auto current sharing. This paper proposes the operation principle, feature analysis and optimization design considerations. On this basis the objectives of high voltage conversion ratio, low voltage/current stress, high power density, high efficiency and high-power applications can be achieved. Some experimental results based on a 500 W prototype converter (24 V to 48 V at low-voltage side, 400 V at high-voltage side are given to verify the theoretical analysis and the effectiveness of the proposed converter.
Multi-Level DC-DC Converter for High Gain Applications
Directory of Open Access Journals (Sweden)
Girish Ganesan R
2013-12-01
Full Text Available The output voltage from most renewable energy sources like photovoltaic arrays and fuel cells will be at low level. This must be stepped up considerably for practical utilization or grid connection. The presented multilevel boost converter DC-DC converter topology consists of the conventional boost converter and voltage doubler stages to provide high voltage gain. The proposed topology uses only one switch along with one inductor, (2N-1 diodes and (2N-1 capacitors for obtaining an output which is N times the conventional boost converter. In this topology, each device blocks only one voltage level. The main advantages of this topology are continuous input current, large gain without high duty cycle or transformer, modularity and use of devices with low voltage ratings. Experimental results obtained from the 100W prototype demonstrate the voltage gain capability of the converter and validates the converter design.
Energy Technology Data Exchange (ETDEWEB)
Kroeger, Claus [Hochschule Aalen (Germany). Wirtschaftsingenieurwesen
2009-07-01
DC-DC-Converters are used in power electronics to adapt different voltage levels of electrical sources and sinks with respect of high efficiency. To minimize electrical losses these power electronic converters always work with switching power semiconductors. This switching principle of the converter is causing a control constraint which limits the achievable performance for the voltage control drastically. This paper presents an optimization for the control sequence in a high dynamic converter control which is based on the dead-beat control design. Thus the non-avoidable control constraint will not be violated. (orig.)
Reliability-Oriented Design of LC Filter in Buck DC-DC Converter
DEFF Research Database (Denmark)
Liu, Yi; Huang, Meng; Wang, Huai;
2015-01-01
State-of-the-art LC filter design of buck DC-DC converter is based on the specifications of voltage and current ripples and constrains in power density and cost. Since lifetime is an important performance factor in reliability critical applications, this digest proposes a method to optimize...... the design of the LC filters from a reliability perspective, among other considerations. It investigates the design freedom between the values of inductor and capacitors, the physical formation of the LC network, and the corresponding electro-thermal stresses of the selected capacitors. The outcome enables...... an optimized LC filter design to fulfill the required lifetime. The theoretical analysis and simulation study are presented which are verified by the experimental results from a buck converter prototype....
Three-port DC-DC converter with new integrated transformer for DC Distribution Systems
DEFF Research Database (Denmark)
Ouyang, Ziwei; Andersen, Michael A. E.
2014-01-01
A new integrated transformer for three-port dc-dc converter is proposed to overcome the power coupling effect existed in some known multiple inputs dc-dc converters. Orthogonal primary windings arrangement and in series connection of diagonal secondary Windings enables a fully power decoupling...
MPP-Tracking DC-DC converters in Photovoltaic applications. Implementation, modeling and analysis
Energy Technology Data Exchange (ETDEWEB)
Leppaeaho, J.
2011-07-01
This thesis provides a comprehensive study of switched-mode dc-dc converters in terms of dynamic characterization, implementation and operational constraints. The study concentrates on the maximum-power-point-tracking converters used in photovoltaic interfacing in order to maximize the power generation. The main objective is to emphasize the differences between the four basic conversion schemes and to analyze the dynamical characteristics of the current-fed converters. Harvesting of solar energy directly into electrical energy is known to be challenging due to the highly varying terminal characteristics of the energy harvesting unit, i.e., generally a photovoltaic generator. The environmental conditions as well as the load determine its characteristics. The operation point of PV generator has to be kept at its maximum-power point in order to maximize the harvested energy. The dc-dc switched-mode converters are conventionally used to interface the energy sources possessing constant-voltage behavior such as batteries or voltage buses but the same converters are also used as a basis for the maximum-power-point-tracking devices. It is observed, however, that such voltage-fed converters are not capable of interfacing a photovoltaic generator optimally because of its current-source nature. Therefore, an additional capacitor is usually added between the source and converter to enhance the constant-voltage properties of the source and to enable the input-voltage-based feedback control. It is known that the dual nature of PV generator enables the use of either input-voltage or input-current feedback control. It is observed, that the input-current control is prone to saturation of the controller and therefore, the input-voltage control is recommended to be used. The use of input-voltage control will, however, force the converter operate as a current-fed converter causing also significant changes to its static and dynamic properties as well as constraints related to the
Agamy, Mohammed; Elasser, Ahmed; Sabate, Juan Antonio; Galbraith, Anthony William; Harfman Todorovic, Maja
2014-09-09
A distributed photovoltaic (PV) power plant includes a plurality of distributed dc-dc converters. The dc-dc converters are configured to switch in coordination with one another such that at least one dc-dc converter transfers power to a common dc-bus based upon the total system power available from one or more corresponding strings of PV modules. Due to the coordinated switching of the dc-dc converters, each dc-dc converter transferring power to the common dc-bus continues to operate within its optimal efficiency range as well as to optimize the maximum power point tracking in order to increase the energy yield of the PV power plant.
Energy Technology Data Exchange (ETDEWEB)
Tang, Lixin [ORNL; Su, Gui-Jia [ORNL
2008-01-01
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.
Power Network impedance effects on noise emission of DC-DC converters
Esteban, M. C.; Arteche, F.; Iglesias, M.; Gimeno, A.; Arcega, F. J.; Johnson, M.; Cooper, W. E.
2012-01-01
The characterization of electromagnetic noise emissions of DC-DC converters is a critical issue that has been analyzed during the desing phase of CMS tracker upgrade. Previous simulation studies showed important variations in the level of conducted emissions when DC-DC converters are loaded/driven by different impedances and power network topologies. Several tests have been performed on real DC-DC converters to validate the Pspice model and simulation results. This paper presents these test results. Conducted noise emissions at the input and at the output terminals of DC-DC converters has been measured for different types of power and FEE impedances. Special attention has been paid to influence on the common-mode emissions by the carbon fiber material used to build the mechanical structure of the central detector. These study results show important recommendations and criteria to be applied in order to decrease the system noise level when integrating the DC-DC.
Wide Temperature Range DC-DC Boost Converters for Command/Control/Drive Electronics Project
National Aeronautics and Space Administration — We shall develop wide temperature range DC-DC boost converters that can be fabricated using commercial CMOS foundries. The boost converters will increase the low...
Energy Factor and Mathematical Modeling for Power DC/DC Converters
Institute of Scientific and Technical Information of China (English)
Fang Lin LUO; Hong YE
2004-01-01
Mathematical modelling for power DC/DC converters is a historical problem accompanying DC/DC conversion technology since 1940's. The traditional mathematical modelling is not available for complex structure converters since the differential equation order increases very high. We have to search other way to establish mathematical modelling for power DC/DC converters. We have theoretically defined a new concept - Energy Factor (EF) in this paper and researched the relations between EF and the mathematical modelling for power DC/DC converters. EF is a new concept in power DC/DC conversion technology, which thoroughly differs from the traditional concepts such as power factor (PF), power transfer efficiency (η), total harmonic distortion (THD) and ripple factor (RF). EF and the subsequential EFv (and EFvD ) can illustrate the system stability, reference response and interference recovery. This investigation is very helpful for system design and DC/DC converters characteristics foreseeing. Two DC/DC converters: Buck converter and Super-Lift Luo-Converter as the samples are analysed in this paper to demonstrate the applications of EF, EFv (and EFvD), PE,SE, VE (and VED ), time constant τ and damping time constant τd .
Integrated Circuit of CMOS DC-DC Buck Converter with Differential Active Inductor
Directory of Open Access Journals (Sweden)
Kaoutar Elbakkar
2011-11-01
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.
Power efficiency improvement of a multi-oscillated current resonant type DC-DC converter
Sato, Tadahiko; Matsuo, Hirofumi; Ota, Hiroyuki; Ishizuka, Yoichi; Higashi, Nobuhiro
2009-01-01
This paper deals with an improvement of a power efficiency of a multi-oscillated current resonant type DC-DC converter. The current resonant type converter employs generally the pulse frequency modulation and its magnetizing inductance is set relatively low. For this reason, the magnetizing current through the converter causes a power loss under a light load. In order to solve this problem, a multi-oscillated current resonant type DC-DC converter has been proposed, and revealed the advantage ...
A current-mode DC-DC buck converter with adaptive zero compensation
Institute of Scientific and Technical Information of China (English)
Yang Ling; Dai Guoding; Xu Chongwei; Liu Yuezhi
2013-01-01
To achieve fast transient response for a DC-DC buck converter,an adaptive zero compensation circuit is presented.The compensation resistance is dynamically adjusted according to the different output load conditions,and achieves an adequate system phase margin under the different conditions.An improved capacitor multiplier circuit is adopted to realize the minimized compensation capacitance size.In addition,analysis of the small-signal model shows the correctness of the mechanism of the proposed adaptive zero compensation technique.A currentmode DC-DC buck converter with the proposed structure has been implemented in a 0.35 μm CMOS process,and the die size is only 800 × 1040 μm2.The experimental results show that the transient undershoot/overshoot voltage and the recovery times do not exceed 40 mV and 30 μs for a load current variation from 100 mA to 1 A.
Chaos analysis and chaotic EMI suppression of DC-DC converters
Zhang, Bo
2014-01-01
Introduces chaos theory, its analytical methods and the means to apply chaos to the switching power supply design DC-DC converters are typical switching systems which have plenty of nonlinear behaviors, such as bifurcation and chaos. The nonlinear behaviors of DC-DC converters have been studied heavily over the past 20 years, yet researchers are still unsure of the practical application of bifurcations and chaos in switching converters. The electromagnetic interference (EMI), which resulted from the high rates of changes of voltage and current, has become a major design criterion in DC-DC co
Mixed-Signal PI Controller in Current-Mode DC-DC Buck Converter for Automotive Applications
Moursy, Yasser; Khalil, Raouf; Lecce, Sergio; Poletto, Vanni; Iskander, Ramy; Louërat, Marie-Minerve
2016-01-01
International audience This paper proposes a fully-integrated solution for the PI compensation circuits in current-mode DC-DC converters used in automotive applications. In such applications, the switching frequencies are low and hence conventional PI compensation circuits employ large capacitors. The proposed analog/mixed-signal PI comprises an analog proportional amplifier and a digital integrator. The analog proportional amplifier provides the required response time and maintains system...
A Protection Circuit for DC-DC Converter with Voltage Doubler
Directory of Open Access Journals (Sweden)
D.Elangovan
2012-12-01
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.
Decentralized Nonlinear Controller Based SiC Parallel DC-DC Converter Project
National Aeronautics and Space Administration — This proposal is aimed at demonstrating the feasibility of a Decentralized Control based SiC Parallel DC-DC Converter Unit (DDCU) with targeted application for...
Directory of Open Access Journals (Sweden)
Sona P
2014-02-01
Full Text Available A high efficiency interleaved ZVS active clamped current fed dc-dc converter is proposed in this paper specially used for fuel cell applications. As the fuel cell output is very low we are in need of a step up dc-dc converter. Here a current fed dc-dc converter is used. Two current fed dc-dc converters are interleaved by connecting their inputs in parallel and outputs in series. With this proposed methodology input current ripples in the fuel cell stacks can be reduced and a regulated output voltage ripples can be obtained. The active clamping circuit used in this model absorbs the turn off voltage spikes hence low voltage devices with low on state resistance can be used.Voltage doubler circuits will give double the output voltage than normal with smaller transformer turns ratio and flexibility. The proposed method is simulated in MATLAB for verifying the accuracy of the proposed design.
Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project
National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex NASA space power electronic systems can be configured using a small number of qualified hybrid DC-DC converter...
Control of improved full-bridge three-level DC/DC converter for wind turbines in a DC grid
DEFF Research Database (Denmark)
Deng, Fujin; Chen, Zhe
2013-01-01
This paper presents an improved full-bridge three-level (IFBTL) dc/dc converter for a wind turbine in a dc grid by inserting a passive filter into the dc/dc converter to improve the performance of the converter. The passive filter can effectively reduce the voltage stress of the medium frequency...... transformer in the IFBTL dc/dc converter. A modulation strategy, including two operation modes, is proposed for the IFBTL dc/dc converter. Then, a voltage balancing control strategy is proposed for the IFBTL dc/dc converter. Furthermore, the control of the wind turbine based on the IFBTL dc/dc converter...... in a dc-grid system is presented. Finally, a small-scale IFBTL dc/dc converter prototype was built and tested in the laboratory, and the results verify the theoretical analysis....
Charger for NiMH batteries based on buck DC/DC converter
Lapčević Vladimir
2014-01-01
In this paper is presented charger for NiMH battery types AA. Charger is realized by Buck DC/DC converter and microcontroller. Microcontroller controls the work of Buck DC/DC converter by pulse width modulation and by measuring the current of battery charging. The current of charging is held constant by power electronics, and the time of charging is set by the user dependent of capacity of the battery. Standard battery chargers enable the recharge of NiMH b...
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)
Novel current resonance DC-DC converter with voltage doubler rectifier for fuel cell system
Kato, Hisatsugu; Matsuo, Hirofumi; Kimura, Takayuki; Sakamoto, Yukitaka
2010-01-01
This paper deals with a novel composite rsonance DC-DC converter for low input voltage, large input current and high output voltsge with the voltage doubler rectifier. which i developed to appl y to the power conditioner of the fuel system. The proposed DC-DC cnverter has the current and voltage resonance fnctions to reduce the switching power loss. The primary and secondary sides of the converter are composed of the current resonant full bridge circuit, and voltage doubler, respectively. For...
Extra-High-Voltage DC-DC Boost Converters Topology with Simple Control Strategy
Directory of Open Access Journals (Sweden)
K. Rajambal
2009-01-01
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.
A fast novel soft-start circuit for peak current-mode DC-DC buck converters
Institute of Scientific and Technical Information of China (English)
Li Jie; Yang Miao; Sun Weifeng; Lu Xiaoxia; Xu Shen; Lu Shengli
2013-01-01
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 μm CMOS process.Experimental results show that the proposed high speed soft-start circuit has achieved less than 50 μs start-up time.The inductor current and the output voltage increase smoothly over the whole load range.
Simulation and Implementation of Interleaved Boost DC-DC Converter for Fuel Cell Application
Directory of Open Access Journals (Sweden)
Ahmad Saudi Samosir
2011-10-01
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.
Ultra-high Efficiency DC-DC Converter using GaN Devices
DEFF Research Database (Denmark)
Ramachandran, Rakesh
2016-01-01
The demands for high efficiency dc-dc power converters are increasing day by day in various applications such as telecommunication, data-centers, electric vehicles and various renewable energy systems. Silicon (Si) has been used as the semiconductor material in majority of the power devices...... properties of GaN devices can be utilized in power converters to make them more compact and highly efficient. This thesis entitled “Ultra-high Efficiency DC-DC Converter using GaN devices” focuses on achieving ultra-high conversion efficiency in an isolated dc-dc converter by the optimal utilization of Ga......N devices. Simple replacement of Si or SiC devices with GaN devices in the converter will not give an expected increase in efficiency or any improvement in the performance of the converter. The use of GaN devices has defined another dimension in the design of power converters, which mainly deals...
Analysis of high voltage step-up nonisolated DC-DC boost converters
Alisson Alencar Freitas, Antônio; Lessa Tofoli, Fernando; Junior, Edilson Mineiro Sá; Daher, Sergio; Antunes, Fernando Luiz Marcelo
2016-05-01
A high voltage step-up nonisolated DC-DC converter based on coupled inductors suitable to photovoltaic (PV) systems applications is proposed in this paper. Considering that numerous approaches exist to extend the voltage conversion ratio of DC-DC converters that do not use transformers, a detailed comparison is also presented among the proposed converter and other popular topologies such as the conventional boost converter and the quadratic boost converter. The qualitative analysis of the coupled-inductor-based topology is developed so that a design procedure can be obtained, from which an experimental prototype is implemented to validate the theoretical assumptions.
Interleaved DC-DC Converter with Discrete Duty Cycle and Open Loop Control
Directory of Open Access Journals (Sweden)
Kroics K.
2016-08-01
Full Text Available The authors present the control principle of the multiphase interleaved DC-DC converter that can be used to vastly reduce output current ripple of the converter. The control algorithm can be easily implemented by using microcontroller without current loop in each phase. The converter works in discontinuous conduction mode (DCM but close to boundary conduction mode (BCM. The DC-DC converter with such a control algorithm is useful in applications that do not require precise current adjustment. The prototype of the converter has been built. The experimental results of the current ripple are presented in the paper.
Interleaved DC-DC Converter with Discrete Duty Cycle and Open Loop Control
Kroics, K.; Sokolovs, A.
2016-08-01
The authors present the control principle of the multiphase interleaved DC-DC converter that can be used to vastly reduce output current ripple of the converter. The control algorithm can be easily implemented by using microcontroller without current loop in each phase. The converter works in discontinuous conduction mode (DCM) but close to boundary conduction mode (BCM). The DC-DC converter with such a control algorithm is useful in applications that do not require precise current adjustment. The prototype of the converter has been built. The experimental results of the current ripple are presented in the paper.
Nonlinear Phenomena and Resonant Parametric Perturbation Control in QR-ZCS Buck DC-DC Converters
Hsieh, Fei-Hu; Liu, Feng-Shao; Hsieh, Hui-Chang
The purpose of this study is to investigate the chaotic phenomena and to control in current-mode controlled quasi-resonant zero-current-switching (QR-ZCS) DC-DC buck converters, and to present control of chaos by resonant parametric perturbation control methods. First of all, MATLAB/SIMULINK is used to derive a mathematical model for QR-ZCS DC-DC buck converters, and to simulate the converters to observe the waveform of output voltages, inductance currents and phase-plane portraits from the period-doubling bifurcation to chaos by changing the load resistances. Secondly, using resonant parametric perturbation control in QR-ZCS buck DC-DC converters, the simulation results of the chaotic converter form chaos state turn into stable state period 1, and improve ripple amplitudes of converters under the chaos, to verify the validity of the proposes method.
Efficient and ripple-mitigating dc-dc converter for residential fuel cell system
Energy Technology Data Exchange (ETDEWEB)
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
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)
A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase-shift modula......This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase...
Robust DC/DC converter control for polymer electrolyte membrane fuel cell application
Wang, Ya-Xiong; Yu, Duck-Hyun; Chen, Shi-An; Kim, Young-Bae
2014-09-01
This study investigates a robust controller in regulating the pulse width modulation (PWM) of a DC/DC converter for a polymer electrolyte membrane fuel cell (PEMFC) application. A significant variation in the output voltage of a PEMFC depends on the power requirement and prevents a PEMFC from directly connecting to a subsequent power bus. DC/DC converters are utilized to step-up or step-down voltage to match the subsequent power bus voltage. In this study, a full dynamic model, which includes a PEMFC and boost and buck DC/DC converters, is developed under MATLAB/Simulink environment for control. A robust PWM duty ratio control for the converters is designed using time delay control (TDC). This control enables state variables to accurately follow the dynamics of a reference model using time-delayed information of plant input and output information within a few sampling periods. To prove the superiority of the TDC performance, traditional proportional-integral control (PIC) and model predictive control (MPC) are designed and implemented, and the simulation results are compared. The efficacies of TDC for the PEMFC-fed PWM DC/DC converters are validated through experimental test results using a 100 W PEMFC as well as boost and buck DC/DC converters.
Very High Frequency Resonant DC/DC Converters for LED Lighting
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
2013-01-01
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...
Efficiency and weight of voltage multiplier type ultra lightweight dc-dc converters
Harrigill, W. T., Jr.; Myers, I. T.
1975-01-01
An analytical and experimental study was made of a capacitor-diode voltage multiplier without a transformer which offers the possibility of high efficiency with light weight. The dc-dc conversion efficiencies of about 94 percent were achieved at output powers of 150 watts at 1000 volts using 8x multiplication. A detailed identification of losses was made, including forward drop losses in component, switching losses, reverse junction capacitance charging losses, and charging losses in the main ladder capacitors.
Novel bidirectional DC-DC converters based on the three-state switching cell
da Silva Júnior, José Carlos; Robles Balestero, Juan Paulo; Lessa Tofoli, Fernando
2016-05-01
It is well known that there is an increasing demand for bidirectional DC-DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC-DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC-DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC-DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC-DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.
DC-DC converters with reduced mass for trackers at the HL-LHC
Affolder, A.; Allongue, B.; Blanchot, G.; Faccio, F.; Fuentes, C.; Greenall, A.; Michelis, S.
2011-11-01
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.
Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1
Lee, F. C.; Mahmoud, M. F.; Yu, Y.
1980-01-01
The standardized control module (SCM) was developed for application in the buck, boost and buck/boost DC-DC converters. The SCM used multiple feedback loops to provide improved input line and output load regulation, stable feedback control system, good dynamic transient response and adaptive compensation of the control loop for changes in open loop gain and output filter time constraints. The necessary modeling and analysis tools to aid the design engineer in the application of the SCM to DC-DC Converters were developed. The SCM functional block diagram and the different analysis techniques were examined. The average time domain analysis technique was chosen as the basic analytical tool. The power stage transfer functions were developed for the buck, boost and buck/boost converters. The analog signal and digital signal processor transfer functions were developed for the three DC-DC Converter types using the constant on time, constant off time and constant frequency control laws.
Critical conditions of saddle-node bifurcations in switching DC-DC converters
Fang, Chung-Chieh
2013-08-01
Although existence of multiple periodic orbits in some DC-DC converters have been known for decades, linking the multiple periodic orbits with the saddle-node bifurcation (SNB) is rarely reported. The SNB occurs in popular DC-DC converters, but it is generally reported as a strange instability. Recently, design-oriented instability critical conditions are of great interest. In this article, average, sampled-data and harmonic balance analyses are applied and they lead to equivalent results. Many new critical conditions are derived. They facilitate future research on the instability associated with multiple periodic orbits, sudden voltage jumps or disappearances of periodic orbits observed in DC-DC converters. The effects of various converter parameters on the instability can be readily seen from the derived critical conditions. New Nyquist-like plots are also proposed to predict or prevent the occurrence of the instability.
Energy Technology Data Exchange (ETDEWEB)
Lai, Jih-Sheng (Blacksburg, VA); Liu, Changrong (Sunnyvale, CA); Ridenour, Amy (Salem, VA)
2009-04-14
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.
A low-delay digital PWM control circuit for DC-DC converters
Ishizuka, Yoichi; Ueno, Masao; Nishikawa, Ichiro; Ichinose, Akira; Matsuo, Hirofumi
2007-01-01
This paper is descried about a proposed scheme of a low-cost digital pulse width modulation (DPWM) control circuit for non-isolated DC-DC converter without A/D converter. Also,real-time PID control technique for DPWM is described. Some experimental results are revealed the proposed circuit and scheme. The purpose of this research is striking a balance between minimizing cost increase by digitalizing of the control circuit of DC-DC converter and speeding up the control circuit.
A new digital control DC-DC converter with peak current -injected control
Kurokawa, Fujio; Sukita, Shohei; Shibata, Yuichiro; Yokoyama, Tomoki; Sasaki, Masahiro; Mimura, Yasuhiro
2008-01-01
This paper presents a new digital control circuit which is able to detect the peak switch current of the high frequency switching dc-dc converter. In this proposed digital control circuit, the peak current-injected control is realized using the combination of the simple dual pulse width modulation analog-to-digital signal converter and the programmed delay circuit. In 100kHz digitally controlled dc-dc converter, it is seen in simulation that the proposed method has no overshoot of the output ...
A Reduced-Part, Triple-Voltage DC-DC Converter for Electric Vehicle Power Management
Energy Technology Data Exchange (ETDEWEB)
Su, Gui-Jia [ORNL; Tang, Lixin [ORNL
2007-01-01
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.
Novel DC/DC Converters For High-Power Distributed Power Systems
Francisco Venustiano, Canales Abarca
2003-01-01
One of the requirements for the next generation of power supplies for distributed power systems (DPSs) is to achieve high power density with high efficiency. In the traditional front-end converter based on the two-stage approach for high-power three-phase DPSs, the DC-link voltage coming from the power factor correction (PFC) stage penalizes the second-stage DC/DC converter. This DC/DC converter not only has to meet the characteristics demanded by the load, but also must process energy w...
A Multiphase, Modular, Bidirectional, Triple-Voltage DC-DC Converter Power Systems
Energy Technology Data Exchange (ETDEWEB)
Su, Gui-Jia [ORNL; Tang, Lixin [ORNL
2008-01-01
Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage [14 V, 42 V, and high voltage (HV)] nets. These will be necessary to accommodate existing 14-V loads as well as efficiently handle new heavy loads at the 42-V net and a traction drive on the HV bus. A low-cost DC-DC converter was proposed for connecting the three voltage nets. It minimizes the number of switches and their associated gate driver components by using two half-bridges and a high-frequency transformer. Another salient feature is that the half bridge on the 42-V bus is also utilized to provide the 14-V bus by operating at duty ratios around an atypical value of 1/3. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft switching. The use of half bridges makes the topology well suited for interleaved multiphase modular configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with an atypical duty ratio on the transformer and a preferred multiphase configuration to minimize capacitor ripple currents.
Lightweight DC-DC Converter with Partial Power Processing and MPPT for a Solar Powered Aircraft
Diab-Marzouk, Ahmad
A lightweight dc-dc partial power processing converter is demonstrated for solar aerospace applications. A system-level model is conceived to determine conformity to payload and target distance objectives, with the Solarship aircraft used as an application example. The concept of partial power processing is utilized to realize a high efficiency lightweight converter that performs Max Peak Power Tracking (MPPT) to transfer power from the aircraft solar array to the high-voltage battery bus. The isolated Cuk is determined to be a suitable converter topology for the application. A small-signal model is derived for control design. The operation of a 400V, 2.7 kW prototype is verified at high frequency (200 kHz), high efficiency (> 98%), small mass (0.604 kg), and uses no electrolytic capacitors. MPPT operation is verified on a 376 V commercial solar installation at The University of Toronto. The prototype serves as an enabling technology for solar aerospace applications.
Controlling DC-DC converters by chaos-based pulse width modulation to reduce EMI
Energy Technology Data Exchange (ETDEWEB)
Li Hong [Department of Mathematics and Computer Science, FernUniversitaet in Hagen, 58084 Hagen (Germany)], E-mail: hong.li@FernUni-Hagen.de; Zhang Bo [School of Electric Power, South China University of Technology, Guangzhou (China); Li Zhong; Halang, Wolfgang A. [Department of Mathematics and Computer Science, FernUniversitaet in Hagen, 58084 Hagen (Germany); Chen Guanrong [Department of Electronic Engineering, City University of Hong Kong, Hong Kong (China)
2009-11-15
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.
Modelling and Simulation of Digital Compensation Technique for dc-dc Converter by Pole Placement
Shenbagalakshmi, R.; Sree Renga Raja, T.
2015-09-01
A thorough and effective analysis of the dc-dc converters is carried out in order to achieve the system stability and to improve the dynamic performance. A small signal modelling based on state space averaging technique for dc-dc converters is carried out. A digital state feedback gain matrix is derived by pole placement technique in order to achieve the stability of a completely controllable system. A prediction observer for the dc-dc converters is designed and a dynamic compensation (observer plus control law) is provided using separation principle. The output is very much improved with zero output voltage ripples, zero peak overshoot, and much lesser settling time in the range of ms and with higher overall efficiency (>90 %).
Optimized photovoltaic generator-water electrolyser coupling through a controlled DC-DC converter
Energy Technology Data Exchange (ETDEWEB)
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
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)
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2014-01-01
Efficiency is one of the main concerns during the design phase of switch mode power supply. Planar magnetics based on PCB windings have the potential to reduce the magnetic manufacturing cost however, one of their main drawbacks comes from their low filling factor and high stray capacitance....... This paper presents an analysis of different planar windings configurations focusing on dc and ac resistances in order to achieve highly efficiency in dc-dc converters. The analysis considers different copper thicknesses form 70 μm up to 1500 μm (extreme copper PCB) taking into account manufacturing...... complexity and challenges. The analysis is focused on a high current inductor for a dc-dc converter for fuel cell applications and it is based on FEM simulations. Analysis and results are verified on a 6 kW dc-dc isolated full bridge boost converter prototype based on fully planar magnetics achieving a peak...
Energy Evaluation for DC/DC Converters in DC-Based Wind Farms
Energy Technology Data Exchange (ETDEWEB)
Max, Lena
2007-02-15
In this thesis the suitability of three topologies for DC/DC converters in a DC wind farm grid is investigated from an energy efficiency and energy production cost point of view. The three selected topologies are the fullbridge converter, the single active bridge converter and the series parallel resonant converter. The losses are calculated for all three topologies as a function of the wind speed considering the losses in the semiconductor components and in the transformer. To obtain the average losses, the losses for each converter are integrated over the wind distribution for different average wind speeds. It is found that the resonant converter has the lowest losses of the three types for the DC wind farm application with power losses of about 2.0 - 2.5 % of the input power and the fullbridge converter has slightly higher losses with 2.3 - 3.5 % losses depending on the position in the wind turbine grid. The single active bridge converter has considerably higher losses than the other two topologies with 3.5 - 5.0 % losses. It is shown that the variable operating conditions create problems for all three converters, and as mentioned the single active bridge converter is most affected by the wide range of operation conditions. When comparing the resonant converter and the fullbridge converter, the fullbridge converter has a smaller transformer as well as lower peak current and peak voltage, but also a higher number of diode modules in the output bridge. Comparing the contribution to the energy production cost for the converters, the topology with the lowest contribution varies between the positions in the wind turbine grid. For some positions, the cost of the higher losses for the fullbridge converter are compensated by lower investment cost for the fullbridge converter compared to the resonant converter. Considering the resonant capacitor, the higher peak voltage and the variable frequency control for the resonant converter, the fullbridge converter is here found
Design of current source DC/DC converter and inverter for 2kW fuel cell application
DEFF Research Database (Denmark)
Andreiciks, A.; Steiks, I.; Krievs, O.;
2013-01-01
of a DC/DC converter and an inverter. In this paper a detailed simulation study of such interfacing converter system comprising a double inductor push-pull step-up DC/DC converter and a cascaded H-bridge inverter has been carried out and further confirmed with experimental results. The power converter...
Five-Level Active-Neutral-Point-Clamped DC/DC Converter
DEFF Research Database (Denmark)
Liu, Dong; Deng, Fujin; Chen, Zhe
2016-01-01
Multi-level converters are getting more and more attentions because of their obvious merits such as lower voltage stress and harmonic, smaller size of output filters, and so on. In this paper, a five-level active-neutral-point-clamped (5L-ANPC) dc/dc converter is proposed for power transfer...
Y-Source Boost DC/DC Converter for Distributed Generation
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede;
2015-01-01
This paper introduces a versatile Y-source boost dc/dc converter intended for distributed power generation, where high gain is often demanded. The proposed converter uses a Y-source impedance network realized with a tightly coupled three-winding inductor for high voltage boosting that is presently...
Optimization with System Damping Restoration for Droop Controlled DC-DC Converters
DEFF Research Database (Denmark)
Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.;
2013-01-01
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...
Five-Level Active-Neutral-Point-Clamped DC/DC Converter
DEFF Research Database (Denmark)
Liu, Dong; Deng, Fujin; Chen, Zhe
Multi-level converters are getting more and more attentions because of their obvious merits such as lower voltage stress and harmonic, smaller size of output filters, and so on. In this paper, a five-level active-neutral-point-clamped (5L-ANPC) dc/dc converter is proposed for power transfer...
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Thomsen, Ole Cornelius;
2011-01-01
, 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...
Trans-inverse (Tx−1) high step-up DC-DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang
2015-01-01
In this paper, a new magnetically coupled single-switch non-isolated dc-dc converter with a high voltage gain is proposed. The new topology utilizes a transformer to boost the output voltage. However, unlike other converter topologies with transformer or coupled magnetics, the voltage gain...
Single Event Burnout in DC-DC Converters for the LHC Experiments
Energy Technology Data Exchange (ETDEWEB)
Claudio H. Rivetta et al.
2001-09-24
High voltage transistors in DC-DC converters are prone to catastrophic Single Event Burnout in the LHC radiation environment. This paper presents a systematic methodology to analyze single event effects sensitivity in converters and proposes solutions based on de-rating input voltage and output current or voltage.
Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit
Dudrik, Jaroslav; BODOR Marcel; TRIP Daniel Nistor
2010-01-01
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.
International Nuclear Information System (INIS)
We introduce a dc/dc boost power converter as a didactic prototype intended to support courses on electric circuit analysis experimentally. The corresponding mathematical model is obtained, the converter is designed and an experimental setup is described, constructed and tested. Simplicity of construction as well as low cost of components renders the feasible introduction of this equipment in undergraduate laboratories. (paper)
Silva-Ortigoza, R.; Silva-Ortigoza, G.; Hernandez-Guzman, V. M.; Saldana-Gonzalez, G.; Marcelino-Aranda, M.; Marciano-Melchor, M.
2012-01-01
We introduce a dc/dc boost power converter as a didactic prototype intended to support courses on electric circuit analysis experimentally. The corresponding mathematical model is obtained, the converter is designed and an experimental setup is described, constructed and tested. Simplicity of construction as well as low cost of components renders…
High Efficiency Interleaved Bi-Directional ZVS DC-DC Converter
DEFF Research Database (Denmark)
Zafar Ullah Khan, M.; Mohsin Naveed, M.; Hussain, Dil Muhammad Akbar
2013-01-01
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 Cool...
Soft switching bidirectional DC-DC converter for ultracapacitor-batteries interface
Energy Technology Data Exchange (ETDEWEB)
Adib, Ehsan; Farzanehfard, Hosein [Dept. of Electrical and Computer Engineering, Isfahan Univ. of Technology (Iran)
2009-12-15
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)
Differential Mode EMI Filter Design for Isolated DC-DC Boost Converter
DEFF Research Database (Denmark)
Makda, Ishtiyaq Ahmed; Nymand, Morten
2014-01-01
A Differential Mode EMI filter for a low input voltage high-current isolated dc-dc boost converter is designed and presented in this paper. The primary side Differential Mode noise voltage is low due to the high transformer turn ratio, however, the input current is very high and since the EMI limit...... is identified first. The DM noise model is then established and based on the harmonic analysis of the noise source voltage waveform, the complete Differential Mode EMI filter, including the filter resonance damping branch, is designed for a 3kW isolated dc-dc boost converter. The noise model and its theoretical...
Fast control technique for high frequency (5MHz) DC/DC integrated converter
Viejo de Frutos, Miriam del; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; García Suárez, Oscar; Cobos Márquez, José Antonio
2010-01-01
A switching frequency of 5 MHz allows the integration in a chip of a low power (10W) DC/DC converter. Although this switching frequency would make feasible a voltage mode control with 1MHz bandwidth, the parasitics and robustness don't allow such a high frequency bandwidth. This paper proposes a fast control technique that helps to optimize the dynamic response of high frequency DC/DC converter. The control proposed and analyzed in this paper is based on the peak current mode control of the o...
Model predictive control of bidirectional isolated DC-DC converter for energy conversion system
Akter, Parvez; Uddin, Muslem; Mekhilef, Saad; Tan, Nadia Mei Lin; Akagi, Hirofumi
2015-08-01
Model predictive control (MPC) is a powerful and emerging control algorithm in the field of power converters and energy conversion systems. This paper proposes a model predictive algorithm to control the power flow between the high-voltage and low-voltage DC buses of a bidirectional isolated full-bridge DC-DC converter. The predictive control algorithm utilises the discrete nature of the power converters and predicts the future nature of the system, which are compared with the references to calculate the cost function. The switching state that minimises the cost function is selected for firing the converter in the next sampling time period. The proposed MPC bidirectional DC-DC converter is simulated with MATLAB/Simulink and further verified with a 2.5 kW experimental configuration. Both the simulation and experimental results confirm that the proposed MPC algorithm of the DC-DC converter reduces reactive power by avoiding the phase shift between primary and secondary sides of the high-frequency transformer and allow power transfer with unity power factor. Finally, an efficiency comparison is performed between the MPC and dual-phase-shift-based pulse-width modulation controlled DC-DC converter which ensures the effectiveness of the MPC controller.
Directory of Open Access Journals (Sweden)
Eka Prasetyono
2015-09-01
Full Text Available Bidirectional DC-DC converter is needed in the energy storage system. The converter topology used in this paper was a non-isolated bidirectional DC-DC buck-boost converter. This converter worked in two ways, which the charging mode stored energy into battery when load current was less than nominal main DC current (set point and discharging mode transferred energy from battery to the load when its current exceeded set point value. Both of these modes worked automatically according to the load current. The charging and discharging currents were controlled by fuzzy logic controller which was implemented on microcontroller ARM Cortex-M4F STM32F407VG. This paper compares two types of fuzzy membership function (triangular and sigmoid in controlling bidirectional DC-DC converter. The results showed that fuzzy logic controller with triangle membership function and sigmoid as control bidirectional DC-DC converter had no significant different response, both had an average error for charging and discharging process under 4% with ripple current on the main DC bus around 0.5%. The computing time of program for fuzzy logic controller with triangular membership functions had 19.01% faster than sigmoid, and fuzzy logic computation time on a microcontroller with hardware floating point was 60% faster than software floating point.
Directory of Open Access Journals (Sweden)
Taizhou Bei
2014-01-01
Full Text Available Considering the disadvantages of the traditional high-gain DC-DC converter such as big size, high voltage stress of switches, and large input current ripple, a novel high-gain interleaved boost converter with coupled-inductor and switched-capacitor was proposed correspondingly and the operation principle together with the steady-state analysis of this converter was also described. Besides, a new control approach-dynamic sliding mode evolution PWM controller (DSME PWM for the novel topological converter based on both dynamic evolution and sliding mode control was also presented. From the simulation results and experimental validation the proposed converter can fulfill high-gain boost, low ripple of both the input current and the output voltage. Furthermore, MPPT technique can be also achieved in a short time by simulation. The efficiency and stability of the converter proposed in this paper can be improved.
Energy Technology Data Exchange (ETDEWEB)
Polenov, Dieter
2010-01-15
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.
Energy Technology Data Exchange (ETDEWEB)
Onar, Omer C [ORNL
2011-01-01
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.
Integrated S-band transmitter with on-chip DC-DC converter and control loop
Brouzes, H.; Geurts, S.; Besselink, M.; Telli, A.; Hek, A.P. de; Bent, G. van der; Vliet, F.E. van
2012-01-01
A highly integrated high-power transmitter has been designed in a high breakdown GaAs MMIC technology. The transmitter includes, on top of an S-Band 10 W class-F HPA, a DC/DC converter and its associated gate driver, the full voltage regulation control loop, which provides a significant step for pha
Quasiperiodicity and Torus Breakdown in a Power Electronic DC/DC Converter
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai; Soukhoterin, Evgeniy; Mosekilde, Erik
2007-01-01
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...
A VHF Class E DC-DC Converter with Self-Oscillating Gate Driver
DEFF Research Database (Denmark)
Andersen, Toke Meyer; Christensen, Søren K.; Knott, Arnold;
2011-01-01
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...
High-voltage boost quasi-Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang;
2014-01-01
A high-voltage gain two-switch quasi-Z-source isolated DC/DC converter has been presented in this study. It consists of a quasi-Z-source network at its input, a push-pull square-wave inverter at its middle, and a voltage-doubler rectifier at its output. When coordinated appropriately, the new...
Multistability and hidden attractors in a multilevel DC/DC converter
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai T.; Mosekilde, Erik
2015-01-01
for the hidden set in most cases has been so complicated that special analytic and/or numerical techniques have been required to locate the set. By simulating the model of a multilevel DC/DC converter that operates in the regime of high feedback gain, the paper illustrates how pulse-width modulated control can...
Computer-aided analysis and simulation of switched dc-dc converters
Lee, F. C.; Yu, Y.
1978-01-01
State space techniques are employed to derive an equivalent nonlinear recurrent time-domain model that describes the switched dc-dc converter behavior exactly. This model is employed effectively to analyze both large signal behavior by propagating the recurrence equation and matching boundary conditions through digital computation and small signal behavior by linearizing it about the equilibrium state.
A high voltage gain quasi Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang;
2014-01-01
A compact quasi-Z-source DC/DC converter is presented with high voltage gain, isolated output, and improved efficiency. The improvements in size and performance were achieved by using a square wave inverter with only two output switches driving an isolating transformer in push-pull mode, followed...
Analysis and design of PPFHB bidirectional DC-DC converter with coupled inductors
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
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...
Analysis of DC/DC Converter Efficiency for Energy Storage System Based on Bidirectional Fuel Cells
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2013-01-01
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 in...
ZVZCS PWM DC-DC Converter with Energy Recovery Clamp
Directory of Open Access Journals (Sweden)
Vladimir Ruscin
2008-01-01
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.
Design of a High Efficiency Boost DC-DC Converter
Institute of Scientific and Technical Information of China (English)
GAO Jing; YAO Suying; XU Jiangtao; SHI Zaifeng
2009-01-01
An accurate circuit of PWM/PFM mode converting and a circuit of auto-adaptively adjusting dimension of power transistor are described. The duty cycle of the signal when the control mode converts can be gained accu-rately by using ratios of currents and capacitances, and an optimal dimension of power transistor is derived with different loads. The converter is designed by 0.35 μm standard CMOS technology. Simulation results indicate that the converter starts work at 0.8 V input voltage. Combined with synchronized rectification, the transfer efficiency is higher than 90% with full load range, and achieves 97.5% at rating output.
A high voltage ratio and low ripple interleaved DC-DC converter for fuel cell applications.
Chang, Long-Yi; Chao, Kuei-Hsiang; Chang, Tsang-Chih
2012-01-01
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.
A Low-Power Asynchronous Step-Down DC-DC Converter for Implantable Devices.
Al-Terkawi Hasib, Omar; Sawan, M; Savaria, Y
2011-06-01
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-μ W load power, while providing efficiency up to 80%. The circuit validating the proposed concepts was fabricated in 0.13- μm complementary metal-oxide semiconductor technology. Experimental test results confirm the expected functionality and performance of the proposed circuit.
Implementation of FPGA based Digital Controller for Controlling Chaos in DC/DC converters
RANJAN Vanaja; LOGAMANI Premalatha
2010-01-01
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 arc...
Study on stability of the voltage-mode DC-DC converters
International Nuclear Information System (INIS)
Stroboscopic maps for voltage-mode converters in the continuous conduction mode (CCM) are build up. The stability of one-periodic point is analyzed together with eigenvalues of Jacobian matrix of discrete-maps. The voltage-mode buck converter is taken as an example, and the results of theoretical analysis and numerical simulation coincide with each other, which shows that the stability analysis of the DC-DC converters is feasible using the discrete-map model. (authors)
A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase-shift modulation scheme, all the switches can realize zero-voltageswitching (ZVS) turn-on and bidirectional power flow can be controlled with phase-shift angle. The operating principles of the converter are descr...
Pulse-width modulated DC-DC power converters
Kazimierczuk, Marian K
2008-01-01
This book studies switch-mode power supplies (SMPS) in great detail. This type of converter changes an unregulated DC voltage into a high-frequency pulse-width modulated (PWM) voltage controlled by varying the duty cycle, then changes the PWM AC voltage to a regulated DC voltage at a high efficiency by rectification and filtering. Used to supply electronic circuits, this converter saves energy and space in the overall system. With concept-orientated explanations, this book offers state-of-the-art SMPS technology and promotes an understanding of the principle operations of PWM converters,
DEFF Research Database (Denmark)
Wang, Haojie; Han, Minxiao; Yan, Wenli;
2016-01-01
It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC) is proposed...
DEFF Research Database (Denmark)
Yang, Xi-jun; Qu, Hao; Yao, Chen;
2014-01-01
As for high power plasma power supply, due to high efficiency and flexibility, multi-channel interleaved multi-stage paralleled Buck DC-DC Converter becomes the first choice. In the paper, two-channel interleaved two- stage paralleled Buck DC-DC Converter powered by three-phase AC power supply...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2013-01-01
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...
Analysis of the coupling behavior of PEM fuel cells and DC-DC converters
Energy Technology Data Exchange (ETDEWEB)
Groetsch, M.; Mangold, M.; Kienle, A. [Max Planck Institute for Dynamics of Complex Technical Systems, Process Synthesis and Process Dynamics Group, Sandtorstrasse 1, 39106 Magdeburg (Germany); Kienle, A. [Otto-von-Guericke-Universitaet Magdeburg, Lehrstuhl fuer Automatisierungstechnik / Modellbildung, Universitaetsplatz 2, 39106 Magdeburg (Germany)
2009-07-01
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. (author)
DC-DC power converter research for Orbiter/Station power exchange
Ehsani, M.
1993-01-01
This project was to produce innovative DC-DC power converter concepts which are appropriate for the power exchange between the Orbiter and the Space Station Freedom (SSF). The new converters must interface three regulated power buses on SSF, which are at different voltages, with three fuel cell power buses on the Orbiter which can be at different voltages and should be tracked independently. Power exchange is to be bi-directional between the SSF and the Orbiter. The new converters must satisfy the above operational requirements with better weight, volume, efficiency, and reliability than is available from the present conventional technology. Two families of zero current DC-DC converters were developed and successfully adapted to this application. Most of the converters developed are new and are presented.
Current Fed Step-up DC/DC Converter for Fuel Cell Inverter Applications
Andreičiks, Aleksandrs; Vitols, Kristaps; Krievs, Oskars; Steiks, Ingars
2009-01-01
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.
Analysis of the Coupling Behavior of PEM Fuel Cells and DC-DC Converters
Directory of Open Access Journals (Sweden)
Achim Kienle
2009-03-01
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.
A suitable model plant for control of the set fuel cell-DC/DC converter
Energy Technology Data Exchange (ETDEWEB)
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
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)
Deivasundari, P.; Geetha, R.; Uma, G.; Murali, K.
2013-07-01
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.
High Voltage Coil Current Sensor for DC-DC Converters Employing DDCC
Directory of Open Access Journals (Sweden)
M. Drinovsky
2015-12-01
Full Text Available Current sensor is an integral part of every switching converter. It is used for over-current protection, regulation and in case of multiphase converters for balancing. A new high voltage current sensor for coil-based current sensing in DC-DC converters is presented. The sensor employs DDCC with high voltage input stage and gain trimming. The circuit has been simulated and implemented in 0.35 um BCD technology as part of a multiphase DC-DC converter where its function has been verified. The circuit is able to sustain common mode voltage on the input up to 40 V, it occupies 0.387*0.345 mm2 and consumes 3.2 mW typically.
Improvement of burst-mode control of piezoelectric transformer based DC/DC converter
International Nuclear Information System (INIS)
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. (paper)
Self-Stable Chaos Control of dc-dc Converter
Institute of Scientific and Technical Information of China (English)
LU Wei-Guo; ZHOU Luo-Wei; WU Jun-Ke
2009-01-01
A new concept related to self-stable chaos control is first put forward,and its theoretical basis and realization are presented from the frequency-domain perspective. With a new analogous-circuit realization of this control its applications in the voltage-mode Buck converter is discussed. The harmonic-balance method is applied to determine the control range of the control parameter.The experiment results given in the last part confirm the validity of the proposed control method.
Soft switching DC/DC converter using auxiliary circuits
Jaroslav Dudrik; Vladimír Ruščin
2008-01-01
A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.
Impact of dielectric deterioration on the conducted EMI emissions in the DC-DC boost converter
Musznicki, Piotr; Schanen, Jean-Luc; Granjon, Pierre; Јuszcz, Jarosław
2011-01-01
International audience The magnitude of emitted noise generated by DC-DC converters depends on their electrical behavior and parameters. Some of these can change during the converter life time, especially due to some deterioration process. In this paper the impact of the dielectric materials aging is presented using both circuit simulation and a digital signal processing method based on Wiener filtering. The change of the total EMI spectrum as a function of the dielectric property has been...
A Three-Phase Bidirectional DC-DC Converter for Automotive Applications
Energy Technology Data Exchange (ETDEWEB)
Su, Gui-Jia [ORNL; Tang, Lixin [ORNL
2008-01-01
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.
Current-Steering Switching Policy for a SIDO Linear-Assisted Hysteretic DC/DC Converter
Martínez García, Herminio; Silva-Martínez, José; Alarcón Cot, Eduardo José; Poveda López, Alberto
2010-01-01
This paper proposes the use of linear-assisted switching power converters in the context of single-inductor dual-output (SIDO) applications. By combining a DC/DC ripplecontrolled switching power converter with the respective voltage linear regulators at each output, improved performance in terms of load and line regulations is obtained. To achieve that aim, a current-steering switching policy is proposed, together with a resource-aware circuit implementation. The ripple-based hysteretic...
Average current control of DC-DC Cuk Converters as Power Factor Corrector
Ashima Kulshreshtha; Anmol R. Saxena
2015-01-01
The era of electronic devices in all loads due to the manufacturing technologies replaced many conventional electrical or mechanical loads including lighting loads where Light Emitting Diodes (LEDs) is becoming an emerging technique with many advantages. High frequency switching dc-dc converter is a new technology to control the load and the supply side simultaneously. Due to additional harmonics generated by these switching converters power factor correction has become a necessit...
Inverse optimal control as an alternative to regulate a Boost DC-DC power converter
Directory of Open Access Journals (Sweden)
Carlos Jesús Vega Pérez
2015-11-01
Full Text Available This article presents the application of the fundamental theory of the inverse optimal control problem for regulation of the output voltage in a Boost DC-DC power converter. The inverse optimal control problem states a priori an optimal control law and a posteriori it proposes the functional cost to be minimized, avoiding the explicit solution of the Hamilton-Jacobi-Bellman equation and, therefore, making easier the solution of the optimal control problem. Some analytical developments are shown here to obtain mathematical expressions needed to perform the inverse optimal control approach on regulation of the output voltage in a Boost power converter circuit under the influence of external disturbances. Numerical routines performed in MATLAB® have shown promising results of the proposed technique by achieving annihilation of the perturbation effect in the system´s model. Future work is focused on experimental verification of this approach on a real prototype of the DC-DC converter.
Development of DC-DC converters for the upgrade of the CMS pixel detector
Energy Technology Data Exchange (ETDEWEB)
Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Sammet, Jan; Wlochal, Michael [RWTH Aachen University (Germany)
2012-07-01
Around 2017, the pixel detector of the CMS experiment at LHC 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 available supply cables. Therefore it is foreseen to place DC-DC converters close to the front-end electronics, allowing to provide the power at higher voltages and thereby to facilitate the supply of the required currents with the present cable plant. The talk introduces the foreseen powering scheme of the pixel upgrade and summarizes the results of system test measurements with CMS pixel sensor modules, radiation tolerant DC-DC converters and the full power supply chain of the pixel detector. In addition, measurements of the converter efficiency and performance before, after and during thermal cycling are presented.
5 kW DC/DC converter for hydrogen generation from photovoltaic sources
Energy Technology Data Exchange (ETDEWEB)
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
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)
Novel Full-bridge ZVS DC-DC Converter with an Clamp Diodes
Guangqun, Nan; Xue, Hu
The two arms of this converter all work at zero-voltage switching condition, that bring many advantages, such as little loss of power, simple control, etc. But these also exists some problems, such as parasitic oscillation on the output rectifier diodes. A novel full-bridge ZVS PWM DC-DC converter which adopts two clamping diodes in the first side of the transformer is proposed to reduce the parasitic oscillation in this paper. In this paper, It heavily analyzes the realization process of their soft-switching and the reason of related issues and solution, we establishes simulation model and simulates using orCAD. Finally,a 5 kW ZVS PWM DC-DC converter Prototype in that TMS320F2812 is the core controlled chip has been set up, and the experiments showed us the validation of the correlative theory.
SUBCONTRACT REPORT: DC-DC Converter for Fuel Cell and Hybrid Vehicles
Energy Technology Data Exchange (ETDEWEB)
Marlino, Laura D [ORNL; Zhu, Lizhi [Ballard Power Systems/Siemens VDO
2007-07-01
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.
Voltage Tracking of a DC-DC Flyback Converter Using Neural Network Control
Directory of Open Access Journals (Sweden)
Wahyu Mulyo Utomo
2012-01-01
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.
A Dual-Input DC-DC Converter Using Clean Energy Power Supplies
Eguchi, Kei
2010-01-01
In this chapter, a serial SC DC-DC converter using clean energy power supplies has been proposed. The validity of the circuit design was conï¬rmed by theoretical analyses, SPICE simulations, and experiments. The proposed converter can realize not only long battery runtime but also small hardware-cost and wide input-range. Concretely, in comparison with the conventional parallel converter using 1.5Ã— step-up SC converters, the proposed converter can achieve 20%
Novel family of quasi-Z-source DC/DC converters derived from current-fed push-pull converters
DEFF Research Database (Denmark)
Chub, Andrii; Husev, Oleksandr; Vinnikov, Dmitri;
2014-01-01
This paper is devoted to the step-up quasi-Z-source dc/dc push-pull converter family. The topologies in the family are derived from the isolated boost converter family by replacing input inductors with the quasi-Z-source network. Two new topologies are proposed, analyzed and compared. Theoretical...
Fuzzy based control of Transformer less Coupled inductor based DC-DC converter
Directory of Open Access Journals (Sweden)
V. Viswanath
2015-11-01
Full Text Available Most of the industrial applications use any one of the basic DC-DC converter configurations namely buck, boost, buck–boost, and Cuk converters. These converters are non-isolating converters. Buck-boost converters use inductors for storing energy from the source and release the same to load or output. This results in high stress across magnetic components. This drawback restricts usage of buck-boost converters to low power applications. Flyback converters popularly have known as buck-boost converters uses transformers for achieving wide range of step down and step up voltages. Coupled inductor based converters or tapped inductor based converters are used for achieving wide input – wide output conversion ratios. Coherent transition between step-down and step-up modes is achieved by a proper control scheme. This paper proposes fuzzy logic based closed loop control scheme for control of converter switches. Theoretical derivations of control parameters with their membership values, mamdani based rules for development of fuzzy rules and simulation results of a coupled inductor based DC-DC converter using MATLAB / SIMULINK are concluded.
Optimization of Shielded PCB Air-Core Toroids for High-Efficiency DC-DC Converters
Orlandi, S; Buso, S; Michelis, S; Fuentes, C A; Kayal, M; Faccio, F; Spiazzi, G
2011-01-01
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.
Integrated Three-Port DC-DC Converter for Photovoltaic (PV) Battery Stand-alone Systems
DEFF Research Database (Denmark)
Ouyang, Ziwei; Andersen, Michael A. E.
2016-01-01
Several power sources such as PV solar arrays and battery are often used to manage the power flow for a photovoltaic (PV) based stand-alone power system due to the fluctuation nature of solar energy resource, and deliver a continuous power to the users in an appropriate form. Traditionally, three...... different single-input single-output (SISO) dc/dc converters would have been used. To reduce the cost and improve the power density of the system, an integrated three-port isolated dc/dc converter is proposed in this paper. It can realize all functions of the energy delivery due to the fluctuation nature...... for PV and battery stand-alone system....
DC-DC Converter Topology Assessment for Large Scale Distributed Photovoltaic Plant Architectures
Energy Technology Data Exchange (ETDEWEB)
Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Sabate, Juan A; Steigerwald, Robert L; Jiang, Yan; Essakiappan, Somasundaram
2011-07-01
Distributed photovoltaic (PV) plant architectures are emerging as a replacement for the classical central inverter based systems. However, power converters of smaller ratings may have a negative impact on system efficiency, reliability and cost. Therefore, it is necessary to design converters with very high efficiency and simpler topologies in order not to offset the benefits gained by using distributed PV systems. In this paper an evaluation of the selection criteria for dc-dc converters for distributed PV systems is performed; this evaluation includes efficiency, simplicity of design, reliability and cost. Based on this evaluation, recommendations can be made as to which class of converters is best fit for this application.
A High Power Density DC-DC Converter for Distributed PV Architectures
Energy Technology Data Exchange (ETDEWEB)
Agamy, Mohammed S; Chi, Song; Elasser, Ahmed; Harfman-Todorovic, Maja; Jiang, Yan; Mueller, Frank; Tao, Fengfeng
2012-06-01
In order to maximize solar energy harvesting capabilities, power converters have to be designed for high efficiency and good MPPT and voltage/current performance. When many converters are used in distributed systems, power density also becomes an important factor as it allows for simpler system integration. In this paper a high power density string dc-dc converter suitable for distributed medium to large scale PV installation is presented. A simple partial power processing topology, implemented with all silicon carbide devices provides high efficiency as well as high power density. A 3.5kW, 100kHz converter is designed and tested to verify the proposed methods.
An adaptive digital controller for satellite medium power DC/DC converter
Skup, Konrad R.; Grudziński, Paweł; Orleański, Orleański
2011-01-01
In this paper the work concerning an adaptive digital controller for satellite medium power DC/DC converters is presented. The adaptive techniques and methods developed in Space Research Centre allows an implemented in VHDL controller to modify its parameters according to detected changes in operating conditions. Inductor entering from discontinuous to continuous current mode and vice versa or moving sampling instants due to changes in duty time are good examples of varying operation...
Inductor based switching DC-DC converter for low voltage power distribution in SLHC
Michelis, S; Marchioro, A; Kayal, M; PH-EP
2007-01-01
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.
An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters
Run Min; Chen Chen; Xiaodong Zhang; Xuecheng Zou; Qiaoling Tong; Qiao Zhang
2014-01-01
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In t...
System Tests with DC-DC Converters for the CMS Silicon Strip Tracker at SLHC
Klein, K; Karpinski, W; Merz, J; Sammet, J
2008-01-01
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.
Integrated on-chip 0.35 μm BiCMOS current-mode DC-DC buck converter
Lee, Chan-Soo; Kim, Nam-Soo; Gendensuren, Munkhsuld; Choi, Jae-Ho; Choi, Joong-Ho
2012-12-01
A current-mode DC-DC buck converter with a fully integrated power module is presented in this article. The converter is implemented using BiCMOS technology in amplifier and power MOSFET in a current sensor. The current sensor is realised by the power lateral double-diffused MOSFET with the aspect ratio much larger than that of a matched p-MOSFET. In addition, BiCMOS technology is applied in the error amplifier for an accurate current sensing and a fast transient response. The DC-DC converter is fabricated with 0.35 µm BiCMOS process. Experimental results show that the fully integrated converter operates at 1.3 MHz switching frequency with a supply voltage of 5 V. The output DC voltage is obtained as expected and the output ripple is controlled to be within 2% with a 30 µH off-chip inductor and 100 µF off-chip capacitor.
A Protection Circuit for DC-DC Converter with Voltage Doubler
D. Elangovan; A.Gopi; Dr.R.Saravanakumar
2012-01-01
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 u...
Coupled Inductor Based High Step-Up DC-DC Converter for Multi Input PV System
Directory of Open Access Journals (Sweden)
G. Shiny Vikram
2014-09-01
Full Text Available With the shortage of the energy and ever increasing of the oil price, research on the renewable and green energy sources, especially the solar arrays and the fuel cells, becomes more and more important. How to achieve high step-up and high efficiency DC/DC converters is the major consideration in the renewable power applications due to the low voltage of PV arrays and fuel cells. In this paper a coupled inductor dc-dc converter for photovoltaic system is proposed. The circuit configuration of the proposed converter is very simple. Thus, the proposed converter has higher step-up and step-down voltage gains than the conventional bidirectional dc–dc boost/buck converter. Under same electric specifications for the proposed converter and the conventional bidirectional boost/buck converter, the average value of the switch current in the proposed converter is less than the conventional bidirectional boost/buck converter. The operating principles have been applied to multi input photovoltaic system and outputs have been observed.
DC-DC buck converters for the CMS Tracker upgrade at SLHC
Energy Technology Data Exchange (ETDEWEB)
Feld, L; Jussen, R; Karpinski, W; Klein, K; Sammet, J, E-mail: Katja.Klein@cern.ch [1. Physikalisches Institut B, RWTH Aachen University, Sommerfeldstrasse 14, 52074 Aachen (Germany)
2011-01-15
The CMS experiment at the Large Hadron Collider (LHC) at CERN, Geneva, is planning major upgrades of its current pixel and strip detectors for the LHC luminosity upgrade, known as the SLHC. Due to the larger channel count and - in case of the strip tracker - increased functionality, the powering scheme adopted today, namely parallel powering of several detector modules, has to be abandoned. Instead, a powering scheme based on the DC-DC conversion technique is foreseen, which would lead to lower power losses in the supply cables, and would allow to reduce the material budget of cables and associated electronic boards in the sensitive detector volume. This paper deals with the development, characterisation and optimisation of DC-DC buck converter prototypes for the upgrades of the CMS pixel and strip detectors at the SLHC.
Efficiency and Cost Comparison of Si IGBT and SiC JFET Isolated DC/DC Converters
DEFF Research Database (Denmark)
Nielsen, Rasmus Ørndrup; Török, Lajos; Munk-Nielsen, Stig;
2013-01-01
based converter and a SiC based converter is compared. Both converters are isolated DC/DC converters and were designed for 5 kW nominal outputs. Test setups for both converters were built and tested. The hardware differences between the two converters are described and performance is compared...
DEFF Research Database (Denmark)
Sanjeevikumar, Padmanaban; Grandi, Gabriele; Wheeler, Patrick;
2015-01-01
This paper presents the novel topology of Photo Voltaic (PV) power generation system with simple Maximum Power Point Tracking (MPPT) algorithm in voltage operating mode. Power circuit consists of high output voltage DC-DC boost converter which maximizes the output of PV panel. Usually traditional...... DC-DC boost converters are used for such application, but they are not the most suitable solution due to output limitation, lower efficiency and require more sensors with complex control algorithm. Further on, the effects of parasitic elements are suppressed, as well as the power transfer efficiency...... of DC-DC converters for PV integration. Hence, to overcome these difficulties this paper investigates a DC-DC boost converter together with the additional parasitic component within the circuit to provide high output voltages for maximizing the PV power generation. The proposed power system circuit...
Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to Obtain High DC Voltage
Directory of Open Access Journals (Sweden)
Meghana G Naik,
2014-11-01
Full Text Available In the present scenario the use of transformer for high voltages in converter circuit reduces the overall operating efficiency due to leakage inductance and use of transformer also increases the operational cost. . Therefore the proposed system is implemented with transformer less DC-DC converter so as to obtain high DC voltage with the use of nine stage Cockcroft-Walton (CW voltage multiplier. The proposed converter operates in CCM (continuous conduction mode, so that the converter switch stress, the switching losses are reduced. The DC voltage at the input of the proposed model is low and is boosted up by boost inductor (Ls in DC-DC converter stage and performs inverter operation. The number of stages in CW-voltage multiplier circuit is applied with low input pulsating DC (AC Voltage voltage where it is getting converted to high DC output voltage. The proposed converter switches operates at two independent frequencies, modulating (fsm andalternating (fsc frequency. The fsm operates at higher frequency of the output while the fsc operates at lower frequency of the desired output voltage ripple and the output ripples can be adjusted by the switch Sc1 and Sc2. The regulation of the output voltage is achieved by controlling the Duty ratio.The simulation is carried over by the MATLABSIMULINK.
Performance Analysis of Various DC-DC Converters with Optimum Controllers for PV Applications
Directory of Open Access Journals (Sweden)
R. Sankarganesh
2014-08-01
Full Text Available Alternative vehicles to Internal Combustion Engines (ICE, for instance the electric vehicle is becoming popular. Electric Vehicles (EV are pollution free and cost effective because the fossil fuel cost increases day by day. These factors make people passion for electric vehicles. Electrical energy demand necessitates charging of electric vehicles using renewable energy. Among the different renewable energy resources, Photovoltaic (PV cells are suitable for EV. The PV output power capacity is still low, so efforts continue to develop the PV converter and its controller, aiming for higher power-extracting efficiency. The PV system requires a proper DC-DC converter with optimum controller to deliver its maximum power. This study analyses the various DC-DC converters such as buck, boost, cuk and modified cuk converters to find the solution for maximum efficiency. In this study in addition to converters, various Maximum Power Point Tracking (MPPT methods, such as Perturb and Observe, Incremental Conductance along with a proposed algorithm called Brain Emotional Learning Based Intelligent Controller (BELBIC has been analyzed. The operation of the BELBIC is based on the emotion processing mechanism in the brain. This intelligent control is stimulated by the limbic system of the mammalian brain. The performance analysis of the converters and MPPT methods are simulated using MATLAB/SIMULINK. Furthermore, experimental results are presented in order to validate the modified cuk converter with proposed BELBIC algorithm.
Finite-time control of DC-DC buck converters via integral terminal sliding modes
Chiu, Chian-Song; Shen, Chih-Teng
2012-05-01
This article presents novel terminal sliding modes for finite-time output tracking control of DC-DC buck converters. Instead of using traditional singular terminal sliding mode, two integral terminal sliding modes are introduced for robust output voltage tracking of uncertain buck converters. Different from traditional sliding mode control (SMC), the proposed controller assures finite convergence time for the tracking error and integral tracking error. Furthermore, the singular problem in traditional terminal SMC is removed from this article. When considering worse modelling, adaptive integral terminal SMC is derived to guarantee finite-time convergence under more relaxed stability conditions. In addition, several experiments show better start-up performance and robustness.
Analysis and Experimental Study of Proportional-Integral Sliding Mode Control for DC/DC Converter
Institute of Scientific and Technical Information of China (English)
ZHANG Li; QIU Shui-sheng
2005-01-01
DC/DC converter using the proportional-integral (PI) sliding mode control (SMC) scheme is investigated, including the selection of the switching surface, the proof of the reaching condition and the existence condition of sliding motion. The sliding regime and the local stability are given. The implementation of the PI SMC is simpler than other SMC schemes and the steady-state error is eliminated. A prototype based on Buck converter is built up. The experimental results show that the dynamic performance and robustness to the parameter variations and external disturbances are improved.
Ultra-Step-Up DC-DC Converter with Integrated Autotransformer and Coupled Inductor
DEFF Research Database (Denmark)
Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang
2016-01-01
duty cycle. Further, an integrated passive regenerative circuit recycles the leakage energy of the coupled magnetics and transfer the leakage energy to the load, which helps to avoid high voltage spikes across the switch. This feature along with low stress on the switching device enables the designer......This paper introduces a new single-switch nonisolated dc-dc converter with very high voltage transfer ratio and reduced semiconductor voltage stress. The converter utilizes an integrated autotransformer and a coupled inductor on the same core to achieve a high step-up voltage gain without extreme...
SOFT-SWITCHED HIGH STEP-UP DC-DC CONVERTER WITH HIGH VOLTAGE GAIN
Directory of Open Access Journals (Sweden)
J.C. PAUL IMMANUEL
2013-04-01
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.
Direct switching control of DC-DC power electronic converters using hybrid system theory
Energy Technology Data Exchange (ETDEWEB)
Zhao, J.; Lin, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wang, C. [Wayne State Univ., Detroit, MI (United States). Dept. of Electrical and Computer Engineering; Wayne State Univ., Detroit, MI (United States). Div. of Engineering Technology
2010-07-01
A direct switching control (DSC) scheme for power electronics converters was described. The system was designed for use in both traditional and renewable energy applications as well as in electric drive vehicles. The proposed control scheme was based on a detailed hybrid system converter model that used model predictive control (MPC), piecewise affine (PWA) approximations and constrained optimal control methods. A DC-DC converter was modelled as a hybrid machine. Switching among different modes of the DC-DC converter were modelled as discrete events controlled by the hybrid controller. The modelling scheme was applied to a Buck converter. The DSC was used to control the switch of the power converter based on a hybrid machine model. Results of the study showed that the method can be used to regulate output voltage and inductor currents. The method also provides fast transient responses and effectively regulates both currents and voltage. The controller can be used to provide immediate responses to dynamic disturbances and output voltage fluctuations. 23 refs., 7 figs.
New non-linear control strategy for non-isolated DC/DC converter with high voltage ratio
Energy Technology Data Exchange (ETDEWEB)
Shahin, A.; Huang, B.; Martin, J.P.; Pierfederici, S.; Davat, B. [Groupe de Recherche en Electronique et en Electrotechnique de Nancy - INPL - Nancy Universite, 2, Avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy Cedex (France)
2010-01-15
In this paper, a non-isolated DC/DC converter with high voltage ratio is proposed to allow the interface between a low voltage power source like fuel cell and a high voltage DC bus. To take into account the low voltage-high density characteristics of power sources, a cascaded structure composed of two sub-converters has been chosen and allows obtaining a high voltage ratio. The choice of each sub-converter is based on the requirements of the source and its performances. Consequently, we have chosen a three-interleaved boost converter as the 1st sub-converter whereas the 2nd sub-converter is a three-level boost converter. The control of the whole system is realized thanks to energetic trajectories planning based on flatness properties of the system. The control of both the current and the balance of voltage across the output serial capacitors of the three-level boost converter is ensured by non-linear controllers based on a new non-linear model. Experimental results allow validating the proposed power architecture and its associated control. (author)
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2013-01-01
This paper introduces a new zero-voltage-switching (ZVS) isolated DC-DC converter with two input ports which can be utilized in hybrid energy systems, for instance, in a fuel cell and super-capacitor system. By fully using two high frequency transformers, the proposed converter can effectively...
Practical Design Guidelines of qZSI Based Step-Up DC/DC Converter
Zakis, Janis; Vinnikov, Dmitri; Roasto, Indrek; Jalakas, Tanel
2010-01-01
This paper presents some design guidelines for a new voltage fed step-up DC/DC isolated converter. The most significant advantage of proposed converter is voltage buck-boost operation on single stage. The most promising application for proposed converter is in the field of distributed power generation e.g. fuel cells or photovoltaic. The most sensitive issues - such as power losses caused by high currents in the input side of converter and high transient overvoltages across the inverter bridge caused by stray inductances were discussed and solved. The proposals and recommendations to overcome these issues are given in the paper. The Selection and design guidelines of converter elements are proposed and explained. The prototype of proposed converter was built and experimentally tested. Some results are presented and evaluated.
Design of Controllers for Single-Input Dual-Output Synchronous DC-DC Buck Converter
Directory of Open Access Journals (Sweden)
S.Augustilindiya
2013-08-01
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.
Comparison of control schemes for a fuel cell hybrid tramway integrating two dc/dc converters
Energy Technology Data Exchange (ETDEWEB)
Fernandez, L.M.; Garcia, P.; Garcia, C.A. [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n, 11202 Algeciras (Cadiz) (Spain); Torreglosa, J.P.; Jurado, F. [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, n 28. 23700 Linares (Jaen) (Spain)
2010-06-15
This paper describes a comparative study of two control schemes for the energy management system of a hybrid tramway powered by a Polymer Electrolyte Membrane (PEM) Fuel Cell (FC) and an Ni-MH battery. The hybrid system was designed for a real surface tramway of 400 kW. It is composed of a PEM FC system with a unidirectional dc/dc boost converter (FC converter) and a rechargeable Ni-MH battery with a bidirectional dc/dc converter (battery converter), both of which are coupled to a traction dc bus. The PEM FC and Ni-MH battery models were designed from commercially available components. The function of the two control architectures was to effectively distribute the power of the electrical sources. One of these control architectures was a state machine control strategy, based on eight states. The other was a cascade control strategy which was used to validate the results obtained. The simulation results for the real driving cycle of the tramway reflected the optimal performance of the control systems compared in this study. (author)
Multi-output DC-DC converters based on diode-clamped converters configuration
DEFF Research Database (Denmark)
Nami, A.; Zare, F.; Ghosh, A.;
2010-01-01
for a diode-clamed inverter in the grid connection systems, where boosting low rectified output-voltage and series DC link capacitors is required. To verify the proposed topology, steady-state and dynamic analyses of a MOB converter are examined. A simple control strategy has been proposed to demonstrate...... the performance of the proposed topology for a double-output boost converter. The topology and its control strategy can easily be extended to offer multiple outputs. Simulation and experimental results are presented to show the validity of the control strategy for the proposed converter....
Non-Smooth Bifurcation and Chaos in a DC-DC Buck Converter
Institute of Scientific and Technical Information of China (English)
QIN Zhi-Ying; LU Qi-Shao
2007-01-01
A direct-current-dorect-current (DC-DC)buck converter with integrated load current feedback is studied with three kinds of Poicaré maps.The external corner-collision bifurcation occurs when the crossing number per period varies,and the internal corner-collision bifurcations occur along with period-doubling and period-tripling bifurcations in this model.The multi-band chaos roots in external corner-collision bifurcation and often grows into l-band chaos.A new kind of chaotic sliding orbits,which is more complex for non-smooth systems,is also found in this model.
Comparison of two different high performance mixed signal controllers for DC/DC converters
DEFF Research Database (Denmark)
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2006-01-01
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 k...
Analysis and Implementation of Dual-ZCS forward DC/DC Converter
Institute of Scientific and Technical Information of China (English)
WANG Jing-mei; LAN Zhong-wei; YU Zhong; WANG Hao-cai
2005-01-01
As the switching frequency in DC/DC converter increases, original 'hard-switch' working mode is not compatible. Another problem is the reliability, which is puzzled in single-ended forward, push-pull or bridge-like structures. In this paper, a new dual-ZCS (zero current switches) forward topology is proposed. The operating principle of soft-switch is analyzed, showing the relationship between voltage and current in time domain. Then how to calculate the key parameters of resonant network is . Finally, a prototype ZCS SMPS is implemented and tested. The results consisted with the analyzing results well, and illustrated the advantages of the proposed structure.
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)
Analysis and design of PPFHB bidirectional DC-DC converter with coupled inductors
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
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 a...
Four Quadrants Integrated Transformers for Dual-input Isolated DC-DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Andersen, Michael A. E.;
2012-01-01
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...... 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...
Optimal Design and Tradeoffs Analysis for Planar Transformer in High Power DC-DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2010-01-01
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.......2-kW full-bridge DC-DC converter prototype employing the improved planar transformer structure has been constructed, over 96% efficiency is achieved and a 2.7% improvement compared to the non-interleaving structure is obtained....
High Current Planar Transformer for Very High Efficiency Isolated Boost DC-DC Converters
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2014-01-01
This paper presents a design and optimization of a high current planar transformer for very high efficiency dc-dc isolated boost converters. The analysis considers different winding arrangements, including very high copper thickness windings. The analysis is focused on the winding ac-resistance a......This paper presents a design and optimization of a high current planar transformer for very high efficiency dc-dc isolated boost converters. The analysis considers different winding arrangements, including very high copper thickness windings. The analysis is focused on the winding ac......-resistance and transformer leakage inductance. Design and optimization procedures are validated based on an experimental prototype of a 6 kW dcdc isolated full bridge boost converter developed on fully planar magnetics. The prototype is rated at 30-80 V 0-80 A on the low voltage side and 700-800 V on the high voltage side...... with a peak efficiency of 97.8% at 80 V 3.5 kW. Results highlights that thick copper windings can provide good performance at low switching frequencies due to the high transformer filling factor. PCB windings can also provide very high efficiency if stacked in parallel utilizing the transformer winding window...
Performance of a spacecraft DC-DC converter breadboard modified for low temperature operation
Gerber, Scott S.; Stell, Chris; Patterson, Richard; Ray, Biswajit
1996-01-01
A 1OW 3OV/5.OV push-pull dc-dc converter breadboard, designed by the Jet Propulsion Laboratory (JPL) with a +50 C to +5 C operating range for the Cassini space probe, was characterized for lower operating temperatures. The breadboard converter which failed to operate for temperatures below -125 C was then modified to operate at temperatures approaching that of liquid nitrogen (LN2). Associated with this low operating temperature range (greater than -196 C) was a variety of performance problems such as significant change in output voltage, converter switching instability, and failure to restart at temperatures below -154 C. An investigation into these problems yielded additional modifications to the converter which improved low temperature performance even further.
High efficiency interleaved bi-directional ZVS DC-DC converter
Zafarullah Khan, M.; Mohsin Naveed, M.; Akbar Hussain, D. M.
2013-06-01
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.
A low noise high efficiency buck DC-DC converter with sigma-delta modulation
Energy Technology Data Exchange (ETDEWEB)
Cai Shujiang; Pi Changming; Yan Wei; Li Wenhong, E-mail: wenhongli@fudan.edu.cn [State Key Laboratory of ASIC and Systems, Fudan University, Shanghai 201203 (China)
2011-07-15
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 {mu}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)
Analysis of Discontinuity Induced Bifurcations in a Dual Input DC-DC Converter
Giaouris, Damian; Banerjee, Soumitro; Mandal, Kuntal; Al-Hindawi, Mohammed M.; Abusorrah, Abdullah; Al-Turki, Yusuf; El Aroudi, Abdelali
DC-DC power converters with multiple inputs and a single output are used in numerous applications where multiple sources, e.g. two or more renewable energy sources and/or a battery, feed a single load. In this work, a classical boost converter topology with two input branches connected to two different sources is chosen, with each branch independently being controlled by a separate peak current mode controller. We demonstrate for the first time that even though this converter is similar to other well known topologies that have been studied before, it exhibits many complex nonlinear behaviors that are not found in any other standard PWM controlled power converter. The system undergoes period incrementing cascade as a parameter is varied, with discontinuous hard transitions between consecutive periodicities. We show that the system can be described by a discontinuous map, which explains the observed bifurcation phenomena. The results have been experimentally validated.
A DC-DC Converter with Wide Input Voltage Range for Fuel Cell and Supercapacitor Application
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
and voltage doubler circuit in secondary side. Boost type converter can limit the output ripple current of the fuel cells; hybrid full-bridge structure can change operating modes according to the different input voltage; phase-shift with duty cycle control scheme is utilized to control the bidirectional power......This paper proposes a novel phase-shift plus duty cycle controlled hybrid bi-directional DC-DC converter based on fuel cells and supercapacitors. The described converter employs two high frequency transformers to couple the half-bridge and full-bridge circuits together in the primary side...... flow flexibly. All the switches can turn on under zero-voltage-switching condition (ZVS). The operating principles of the converter are described in details, and the experimental results based on the prototype controlled by DSP are presented to verify the validity of the analysis and design....
Directory of Open Access Journals (Sweden)
Dhananjay Choudhary
2014-08-01
Full Text Available The two basic topologies of switch mode DC-DC converters (Buck and Boost are analyzed with a view of their use in PV (photovoltaic systems, as the photovoltaic generator exhibits non-linear characteristics due to the change in environmental condition and load variation. As the efficiency of PV panels is low it becomes mandatory to extract maximum power from the PV panel at a given period of time. Several MPPT algorithms with different types of converters are being proposed for extracting maximum power from the PV panel. It is found that the nature of load plays an important role in the choice of topology. This paper investigates the implementation issues of Incremental Conductance method with Buck and Boost Converters. Mathematical analysis and desirable steady-state operating point of the converters are derived to give satisfactory maximum power point tracking operation.
Time delay control for fuel cells with bidirectional DC/DC converter and battery
Energy Technology Data Exchange (ETDEWEB)
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
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)
Architectures and Control of Submodule Integrated DC-DC Converters for Photovoltaic Applications
Energy Technology Data Exchange (ETDEWEB)
Olalla, C; Clement, D; Rodriguez, M; Maksimovic, D
2013-06-01
This paper describes photovoltaic (PV) module architectures with parallel-connected submodule-integrated dc-dc converters (subMICs) that improve efficiency of energy capture in the presence of partial shading or other mismatch conditions. The subMICs are bidirectional isolated dc-dc converters capable of injecting or subtracting currents to balance the module substring voltages. When no mismatches are present, the subMICs are simply shut down, resulting in zero insertion losses. It is shown that the objective of minimum subMIC power processing can be solved as a linear programming problem. A simple close-to-optimal distributed control approach is presented that allows autonomous subMIC control without the need for a central controller or any communication among the subMICs. Furthermore, the proposed control approach is well suited for an isolated-port architecture, which yields additional practical advantages including reduced subMIC power and voltage ratings. The architectures and the control approach are validated by simulations and experimental results using three bidirectional flyback subMICs attached to a standard 180-W, 72-cell PV module, yielding greater than 98% module-level power processing efficiency for a mismatch less than 25%.
A DC-DC converter based powering scheme for the upgrade of the CMS pixel detector
Feld, L.; Karpinski, W.; Klein, K.; Merz, J.; Sammet, J.; Wlochal, M.
2011-11-01
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.
Design of a total-dose radiation hardened monolithic CMOS DC-DC boost converter
Energy Technology Data Exchange (ETDEWEB)
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
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)
A Compact, Soft-Switching DC-DC Converter for Electric Propulsion
Button, Robert; Redilla, Jack; Ayyanar, Raja
2003-01-01
A hybrid, soft-switching, DC-DC converter has been developed with superior soft switching characteristics, high efficiency, and low electro-magnetic interference. This hybrid topology is comprised of an uncontrolled bridge operating at full pulse-width, and a controlled section operating as a conventional phase modulated converter. The unique topology is able to maintain zero voltage switching down to no load operating conditions. A breadboard prototype was developed and tested to demonstrate the benefits of the topology. Improvements were then made to reduce the size of passive components and increase efficiency in preparation for packaging. A packaged prototype was then designed and built, and several innovative packaging techniques are presented. Performance test data is presented that reveals deficiencies in the design of the power transformer. A simple redesign of the transformer windings eliminated the deficiency. Future plans to improve the converter and packaging design are presented along with several conclusions.
Systematic design approach of fuzzy PID stabilizer for DC-DC converters
Energy Technology Data Exchange (ETDEWEB)
Guesmi, K.; Essounbouli, N.; Hamzaoui, A. [CReSTIC, IUT de Troyes 09, rue de Quebec BP. 396, 10026 Troyes (France)
2008-10-15
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. (author)
ASIC and FPGA based DPWM architectures for single-phase and single-output DC-DC converter: a review
Chander, Subhash; Agarwal, Pramod; Gupta, Indra
2013-12-01
Pulse width modulation (PWM) has been widely used in power converter control. This paper presents a review of architectures of the Digital Pulse Width Modulators (DPWM) targeting digital control of switching DC-DC converters. An attempt is made to review the reported architectures with emphasis on the ASIC and FPGA implementations in single phase and single-output DC-DC converters. Recent architectures using FPGA's advanced resources for achieving the resolution higher than classical methods have also been discussed. The merits and demerits of different architectures, and their relative comparative performance, are also presented. The Authors intention is to uncover the groundwork and the related references through this review for the benefit of readers and researchers targeting different DPWM architectures for the DC-DC converters.
Directory of Open Access Journals (Sweden)
Zheng Wang
2016-01-01
Full Text Available Three-port isolated (TPI bidirectional DC/DC converters have three energy ports and offer advantages of large voltage gain, galvanic isolation ability and high power density. For this reason this kind of converters are suitable to connect different energy sources and loads in electric and hybrid vehicles. The purpose of this paper is to propose chaotic modulation and the related control scheme for TPI bidirectional DC/DC converters, in such a way that the switching harmonic peaks can be suppressed in spectrum and the conducted electromagnetic interference (EMI is reduced. Two chaotic modulation strategies, namely the continuously chaotic modulation and the discretely chaotic modulation are presented. These two chaotic modulation strategies are applied for TPI bidirectional DC/DC converters with shifted-phase angle based control and phase-shifted PWM control. Both simulation and experiments are given to verify the validity of the proposed chaotic modulation-based control schemes.
Planar integrated magnetics design in wide input range DC-DC converter for fuel cell application
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Thomsen, Ole Cornelius;
2010-01-01
, 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...
DC-DC converters in 0.35μm CMOS technology
Michelis, S.; Allongue, B.; Blanchot, G.; Faccio, F.; Fuentes, C.; Orlandi, S.; Saggini, S.; Cengarle, S.; Ongaro, F.
2012-01-01
In view of the upgrade of the LHC experiments, we are developing custom DC/DC converters for a more efficient power distribution scheme. A new prototype have been integrated in ASICs in the selected 0.35μm commercial high voltage technology that has been successfully tested for all radiation effects: TID, displacement damage and Single Event Burnout. This converter has been optimized for high efficiency and improved radiation tolerance. Amongst the new features the most relevant are the presence of internal linear regulators, protection circuits with a state-machine and a new pinout for a modified assembly in package in order to reduce conductive losses. This paper illustrates the design of the prototype followed by functional and radiation tests.
Electrothermal model of choking-coils for the analysis of dc-dc converters
Energy Technology Data Exchange (ETDEWEB)
Gorecki, Krzysztof, E-mail: gorecki@am.gdynia.pl [Gdynia Maritime University, Department of Marine Electronics, Morska 83, Gdynia (Poland); Detka, Kalina [Pomeranian Higher School in Gdynia, Opata Hackiego 8-10, Gdynia (Poland)
2012-09-01
The paper concerns modelling the choking-coil for the needs of the electrothermal analysis of dc-dc converters. A new electrothermal model of the choking-coil is proposed. This model is dedicated for SPICE software and it takes into account nonlinearity of the dependences of the inductance on the current, selfheating and mutual thermal interactions between the core and the winding. The structure of this model is described in detail and its correctness is experimentally verified for the choking-coils with the ferrite and powder cores. Both the characteristics of the choking-coils and the buck converter with these choking-coils were considered. The satisfying agreement between the results of calculations and measurements is obtained.
SSP Technology Investigation of a High-Voltage DC-DC Converter
Pappas, J. A.; Grady, W. M.; George, Patrick J. (Technical Monitor)
2002-01-01
The goal of this project was to establish the feasibility of a high-voltage DC-DC converter based on a rod-array triggered vacuum switch (RATVS) for the Space Solar Power system. The RATVS has many advantages over silicon and silicon-carbide devices. The RATVS is attractive for this application because it is a high-voltage device that has already been demonstrated at currents in excess of the requirement for an SSP device and at much higher per-device voltages than existing or near-term solid state switching devices. The RATVS packs a much higher specific power rating than any solid-state device and it is likely to be more tolerant of its surroundings in space. In addition, pursuit of an RATVS-based system would provide NASA with a nearer-term and less expensive power converter option for the SSP.
Conventional control and fuzzy control of a dc-dc converter for machine drive
Energy Technology Data Exchange (ETDEWEB)
Radoi, C.; Florescu, A. [Department of Power Electronics `Politecnica` University Bucharest (Romania)
1997-12-31
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.
Design of high efficiency dual-mode buck DC-DC converter
Energy Technology Data Exchange (ETDEWEB)
Lai Xinquan; Zeng Huali; Ye Qiang; He Huisen; Zhang Shasha; Sun Yuqing, E-mail: zenghuali4213@126.com, E-mail: xqlai@mail.xidian.edu.cn [Institute of Electronic CAD, Xidian University, Xi' an 710071 (China)
2010-11-15
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 {mu}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%.
A Reduced-Part, Triple-Voltage DC-DC Converter for EV/HEV Power Management
Energy Technology Data Exchange (ETDEWEB)
Su, Gui-Jia [ORNL; Tang, Lixin [ORNL
2009-01-01
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.
DEFF Research Database (Denmark)
Ouyang, Ziwei; Andersen, Michael A. E.; Thomsen, Ole Cornelius
2012-01-01
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....... 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...
DEFF Research Database (Denmark)
Park, Kiwoo; Chen, Zhe
2015-01-01
This study presents a control strategy and its dynamic analysis of a high-power dc-dc converter, which is constructed with the parallel-connected single active bridge (SAB) dc-dc converters for dc-grid wind farm applications. The structural and operational characteristics of the SAB dc-dc converter...... have several advantages for high-power applications, and the modular concept of the parallel-connected converter is highly beneficial especially for offshore wind farm applications in terms of maintenance cost and fault tolerance. To justify the feasibility of the parallel-connected SAB dc-dc converter...
Park, Jungyong; Kim, Shiho
2012-06-01
An analog maximum power point tracking (MPPT) circuit for a thermoelectric generator (TEG) is proposed. We show that the peak point of the voltage conversion gain of a boost DC-DC converter with an input voltage source having an internal resistor is the maximum power point of the TEG. The key characteristic of the proposed MPPT controller is that the duty ratio of the input clock pulse to the boost DC-DC converter shifts toward the maximum power point of the TEG by seeking the peak gain point of the boost DC-DC converters. The proposed MPPT technique provides a simple and useful analog MPPT solution, without employing digital microcontroller units.
DC-DC converters for the upgrades of the CMS tracker
International Nuclear Information System (INIS)
Within the present decade, it is foreseen to gradually increase the instantaneous luminosity of the LHC to 1-2.1034 cm-2s-1. Around 2020, it is intended to increase the luminosity further, to about 5.1034 cm-2s-1. To ensure and improve its physics performance, CMS is going to exchange its pixel detector around 2016. Four years later the complete tracker is going to be replaced by a new development. The use of DC-DC converters is foreseen for both of these upgrades. Radiation tolerant converters developed by working groups at CERN and Aachen match the requirements of the new pixel detector already. However, further work is required to integrate the converters on system level and to ensure their save and reliable operation. The status of this work is presented. Building a new tracking detector equipped with converters, raises several additional challenges. In particular the noise performance of the converters and their efficiency at large conversion ratios still has to be improved. The coil, used by the converters to buffer energy, has a significant impact on both of these issues. Effort has been put into the optimization of converter coils, as well as into the exploration and minimization of noise radiated by the coils. The talk gives a summary of the results of this work.
Advanced DC-DC converter for power conditioning in hydrogen fuel cell systems
Energy Technology Data Exchange (ETDEWEB)
Kovacevic, G.; Tenconi, A.; Bojoi, R. [Department of Electrical Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)
2008-06-15
The fuel cell (FC) generators can produce electric energy directly from hydrogen and oxygen. The DC voltage generated by FC is generally low amplitude and it is not constant, depending on the operating conditions. Furthermore, FC systems have dynamic response that is slower than the transient responses typically requested by the load. For this reason, in many applications the FC generators must be interfaced with other energy/power sources by means of an electronic power converter. An advanced full-bridge (FB) DC-DC converter, which effectively achieves zero-voltage switching and zero-current switching (ZVS-ZCS), is proposed for power-conditioning (PC) in hydrogen FC applications. The operation and features of the converter are analyzed and verified by simulations results. The ZVS-ZCS operation is obtained by means of a simple auxiliary circuit. Introduction of the soft-switching operation in PC unit brings improvements not only from the converter efficiency point of view, but also in terms of increased converter power density. Quantitative analysis of hard and soft-switching operating of the proposed converter is also made, bringing in evidence the benefits of soft-switching operation mode. The proposed converter can be a suitable solution for PC in hydrogen FC systems, especially for the medium to high-power applications. (author)
DC-DC converters for the upgrades of the CMS tracker
Energy Technology Data Exchange (ETDEWEB)
Sammet, Jan; Feld, Lutz; Karpinski, Waclaw; Klein, Katja; Merz, Jennifer; Wehner, Jakob; Wlochal, Michael [RWTH Aachen University, I. Physikalisches Instiut B (Germany)
2011-07-01
Within the present decade, it is foreseen to gradually increase the instantaneous luminosity of the LHC to 1-2.10{sup 34} cm{sup -2}s{sup -1}. Around 2020, it is intended to increase the luminosity further, to about 5.10{sup 34} cm{sup -2}s{sup -1}. To ensure and improve its physics performance, CMS is going to exchange its pixel detector around 2016. Four years later the complete tracker is going to be replaced by a new development. The use of DC-DC converters is foreseen for both of these upgrades. Radiation tolerant converters developed by working groups at CERN and Aachen match the requirements of the new pixel detector already. However, further work is required to integrate the converters on system level and to ensure their save and reliable operation. The status of this work is presented. Building a new tracking detector equipped with converters, raises several additional challenges. In particular the noise performance of the converters and their efficiency at large conversion ratios still has to be improved. The coil, used by the converters to buffer energy, has a significant impact on both of these issues. Effort has been put into the optimization of converter coils, as well as into the exploration and minimization of noise radiated by the coils. The talk gives a summary of the results of this work.
Large step-down DC-DC converters with reduced current stress
Energy Technology Data Exchange (ETDEWEB)
Ismail, Esam H. [Department of Electrical Engineering, College of Technological Studies, P.O. Box 35007, 36051 Al-Shaab (Kuwait)
2009-02-15
In this paper, several DC-DC converters with large voltage step-down ratios are introduced. A simple modification in the output section of the conventional buck and quadratic converters can effectively extend the duty-cycle range. Only two additional components (an inductor and diode) are necessary for extending the duty-cycle range. The topologies presented in this paper show an improvement in the duty-cycle (about 40%) over the conventional buck and quadratic converters. Consequently, they are well suited for extreme step-down voltage conversion ratio applications. With extended duty-cycle, the current stress on all components is reduced, leading to a significant improvement of the system losses. The principle of operation, theoretical analysis, and comparison of circuit performances with other step-down converters is discussed regarding voltage and current stress. Experimental results of one prototype rated 40-W and operating at 100 kHz are provided in this paper to verify the performance of this new family of converters. The efficiency of the proposed converters is higher than the quadratic converters. (author)
A 10 kW dc-dc converter using IGBTs with active snubbers. [Insulated Gate Bipolar Transistor
Masserant, Brian J.; Shriver, Jeffrey L.; Stuart, Thomas A.
1993-01-01
This full bridge dc-dc converter employs zero voltage switching (ZVS) on one leg and zero current switching (ZCS) on the other. This technique produces exceptionally low IGBT switching losses through the use of an active snubber that recycles energy back to the source. Experimental results are presented for a 10 kW, 20 kHz converter.
A Family of Step-up DC/DC Converters with Fast Dynamic Response for Low Power Applications
DEFF Research Database (Denmark)
N. Soltani, Mohsen; Mostaan, Ali; Siwakoti, Yam Prasad;
2016-01-01
This paper presents a family of novel step-up DC/DC converters which do not have a right half plane zero in their transfer function resulting in faster dynamic behavior of the converters under the load variation. In addition, the voltage stress on all the active switches and diodes is as low as t...
DC / DC Converter for the conditioning of the photovoltaic energy - modeling and command strategy
Directory of Open Access Journals (Sweden)
Z. SABIRI
2015-02-01
Full Text Available Demand for energy, especially electricity, throughout the world, is increasingly growing rapidly. Renewable energy: wind, solar, geothermal, and hydroelectric and biomass provides substantial benefits for our climate, our health, and our economy. However it needs more investigations in terms of research. A special attention should be given on the optimization of energy production and its own integration in grids especially when the resources become multiple. The contribution of our researches is to study the technical and physical aspects to optimize the energy management in a multi-source system dedicated to rural area applications. The multi-source system is based on photovoltaic panels, wind turbine, solar PV and storage batteries. In this paper, we present the modeling and simulation of the part composed of photovoltaic source and its DC / DC converter.
A dual VCDL DLL based gate driver for zero-voltage-switching DC-DC converter
Energy Technology Data Exchange (ETDEWEB)
Tian Xin; Liu Xiangxin; Li Wenhong, E-mail: wenhongli@fudan.edu.c [State Key Laboratory of ASIC and System, Fudan University, Shanghai 201203 (China)
2010-07-15
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 {mu}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.
DC-DC switching converter based power distribution vs serial power distribution EMC strategies
Arteche, F; Iglesias, M; Rivetta, C; Arcega, F G; Vila, I
2009-01-01
This paper presents a detailed and comparative analysis from the electromagnetic compatibility point of view of the proposed power distributions for the SLHC tracker up-grade. The main idea is to identify and quantify the noise sources, noise distribution at the system level and the sensitive areas in the front-end electronics corresponding to both proposed topologies: The DC-DC converter based power distribution and the serial power distribution. These studies will be used to define critical points on both systems to be studied and prototyped to ensure the correct integration of the system taking critically into account the electromagnetic compatibility. This analysis at the system level is crucial to ensure the final performance of the detector using non conventional power distributions, avoiding interference problems and excessive losses that can lead to catastrophic failures or expensive and un-practical solutions.
Online humidification diagnosis of a PEMFC using a static DC-DC converter
Energy Technology Data Exchange (ETDEWEB)
Hinaje, M.; Sadli, I.; Martin, J.-P.; Thounthong, P.; Rael, S.; Davat, B. [GREEN - Institut National Polytechnique de Lorraine 2, Avenue de la Foret de Haye, 54516 Vandoeuvre-les-Nancy (France)
2009-03-15
This paper deals with the online checking of the humidification of a Proton Exchange Membrane Fuel Cell (PEMFC). Indeed, drying or flooding can decrease the performance of the PEMFC and even lead to its destruction. An online humidification diagnosis can allow a real-time control. A good indicator of the membrane humidification state is its internal resistance. As known, the membrane ionic conductivity increases with the membrane water content. This resistance can be calculated at high frequency by dividing the voltage variation by the current variation. The proposed scheme makes use of measurements of current and voltage ripples coming from the association of a static DC-DC converter and the fuel cell. The experiment thus consists in computing the internal resistance in wet and dry conditions. (author)
Multi-cell DC-DC converters : modelling, analysis and control
International Nuclear Information System (INIS)
This paper is devoted to modeling of a two-cell DC/DC buck converter, to the analysis of its behavior and to the design of control methods that yield to improve its performances. Various numerical simulations and dynamical aspects of this system are illustrated in the time domain and in the parameter space. Without control, the system may present many undesirable behaviors such as sub-harmonics and chaotic oscillations. The proposed controllers are able to widen the stability range of the system. Optimum values of parameters giving rise to fast response while maintaining stable periodic behavior are given in closed form. However, it is detected that in a certain region of the parameter space, the stabilized periodic orbit may coexist with a chaotic attractor. Boundary between basins of attraction are obtained by means of numerical simulations.
Bifurcation boundary conditions for current programmed PWM DC-DC converters at light loading
Fang, Chung-Chieh
2012-10-01
Three types of bifurcations (instabilities) in the PWM DC-DC converter at light loading under current mode control in continuous-conduction mode (CCM) or discontinuous-conduction mode (DCM) are analysed: saddle-node bifurcation (SNB) in CCM or DCM, border-collision bifurcation during the CCM-DCM transition, and period-doubling bifurcation in CCM. Different bifurcations occur in some particular loading ranges. Bifurcation boundary conditions separating stable regions from unstable regions in the parametric space are derived. A new methodology to analyse the SNB in the buck converter based on the peak inductor current is proposed. The same methodology is applied to analyse the other types of bifurcations and converters. In the buck converter, multiple stable/unstable CCM/DCM steady-state solutions may coexist. Possibility of multiple solutions deserves careful study, because an ignored solution may merge with a desired stable solution and make both disappear. Understanding of SNB can explain some sudden disappearances or jumps of steady-state solutions observed in switching converters.
Performance of a Voltage Step-Up/Step-Down Transformerless DC/DC Converter: Analytical Model
Suskis, P.; Rankis, I.
2012-01-01
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.
A Bidirectional, Triple-Voltage DC-DC Converter for Hybrid and Fuel Cell Vehicle Power Systems
Energy Technology Data Exchange (ETDEWEB)
Su, Gui-Jia [ORNL; Tang, Lixin [ORNL
2007-01-01
Electrical power systems in future hybrid and fuel cell vehicles may employ three voltage (14V, 42V and high voltage (HV)) nets. These will be necessary to accommodate existing 14V loads as well as efficiently handle new heavy loads at the 42V net and an electrical traction drive on the HV bus. A low-cost bi-directional dc-dc converter was proposed in (10) for connecting the three voltage nets. The converter consists of two half-bridges and a high-frequency transformer; thus minimizing the number of switching devices and their associated gate driver components. One salient feature is that the half-bridge on the 42V bus is also utilized to provide the 14V bus by operating its duty ratio around an atypical value of 1/3. This eliminates the need for an additional 14V/42V converter. Moreover, it makes use of the parasitic capacitance of the switches and the transformer leakage inductance for soft-switching; no extra active switches or passive resonant components are required. The use of half-bridges makes the topology suitable for interleaved multi-phase configurations as a means to increase the power level because the capacitor legs can be shared. This paper presents simulation and experimental results on an interleaved two-phase arrangement rated at 4.5 kW. Also discussed are the benefits of operating with the atypical duty ratio on the transformer and a preferred multi-phase configuration to minimize capacitor ripple currents.
Bailey, Wendell; Wen, Hauming; Yang, Yifeng; Forsyth, Andrew; Jia, Chungjiang
A dc-dc converter has been developed for retrofitting inside the vacuum space of the HTS rotor of a synchronous generator. The heavy copper sections of the current leads used for energising the HTS field winding were replaced by cryogenic power electronics; consisting of the converter and a rotor control unit. The converter board was designed using an H-bridge configuration with two 5A rated wires connecting the cryogenic boards to the stator control board located on the outside of the generator and drawing power from a (5A, 50 V) dc power source. The robustness of converter board was well demonstrated when it was powered up from a cold start at 82K. When charging the field winding with moderate currents (30A), the heat in-leak to the 'cold' rotor core was only 2W. It continued to function down to 74K, surviving several quenches. However, the quench protection function failed when injecting 75A into the field winding, resulting in the burn out of one of the DC-link capacitors. The magnitudes of the critical currents measured with the original current leads were compared to the quench currents, which was defined as the current which triggered quench protection protocol. The difference between the two currents was rather large, (∼20A). However, additional measurements using a single HTS coil in liquid nitrogen found that this reduction should not be so dramatic and in the region of 4A. Our conclusions identified the converter's switching voltage and its operating frequency as two parameters, which could have contributed to lowering the quench current. Magnetic fields and eddy currents are expected to be more prominent the field winding and its impact on the converter also need further investigation.
Energy Technology Data Exchange (ETDEWEB)
Agamy, Mohammed S; Harfman-Todorovic, Maja; Elasser, Ahmed; Steigerwald, Robert L; Sabate, Juan A; Chi, Song; McCann, Adam J; Zhang, Li; Mueller, Frank
2012-09-01
In this paper a DC-DC power converter for distributed photovoltaic plant architectures is presented. The proposed converter has the advantages of simplicity, high efficiency, and low cost. High efficiency is achieved by having a portion of the input PV power directly fed forward to the output without being processed by the converter. The operation of this converter also allows for a simplified maximum power point tracker design using fewer measurements
High efficiency and low electromagnetic interference boost DC-DC converter
Yajun, Li; Xinquan, Lai; Qiang, Ye; Bing, Yuan
2014-04-01
A synchronous boost DC-DC converter with an adaptive dead time control (DTC) circuit and anti-ringing circuit is presented. The DTC circuit is used to provide adjustable dead time and zero inductor current detection for power transistors and therefore, a high efficiency is achieved by minimizing power losses, such as the shoot-through current loss, the body diode conduction loss, the charge-sharing loss and the reverse inductor current loss. Simultaneously, a novel anti-ringing circuit controlled by the switching sequence of power transistors is developed to suppress the ringing when the converter enters the discontinuous conduction mode (DCM) for low electromagnetic interference (EMI) and additional power savings. The proposed converter has been fabricated in a 0.6 μm CDMOS technology. Simulation and experimental results show that the power efficiency of the boost converter is above 81% under different load currents from 10 to 250 mA and a peak efficiency of 90% is achieved at about 100 mA. Moreover, the ringing is easily suppressed by the anti-ringing circuit and therefore the EMI noise is attenuated.
An optimal current observer for predictive current controlled buck DC-DC converters.
Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao
2014-01-01
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally.
An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters
Directory of Open Access Journals (Sweden)
Run Min
2014-05-01
Full Text Available In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally.
An optimal current observer for predictive current controlled buck DC-DC converters.
Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao
2014-01-01
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally. PMID:24854061
A High-Efficiency Monolithic DC-DC PFM Boost Converter with Parallel Power MOS Technique
Directory of Open Access Journals (Sweden)
Hou-Ming Chen
2013-01-01
Full Text Available This paper presents a high-efficiency monolithic dc-dc PFM boost converter designed with a standard TSMC 3.3/5V 0.35 μm CMOS technology. The proposed boost converter combines the parallel power MOS technique with pulse-frequency modulation (PFM technique to achieve high efficiency over a wide load current range, extending battery life and reducing the cost for the portable systems. The proposed parallel power MOS controller and load current detector exactly determine the size of power MOS to increase power conversion efficiency in different loads. Postlayout simulation results of the designed circuit show that the power conversion is 74.9–90.7% efficiency over a load range from 1 mA to 420 mA with 1.5 V supply. Moreover, the proposed boost converter has a smaller area and lower cost than those of the existing boost converter circuits.
DEFF Research Database (Denmark)
Meng, Lexuan; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez;
2015-01-01
Droop control by means of virtual resistance (VR) control loops can be applied to paralleled dc-dc converters for achieving autonomous equal power sharing. However, equal power sharing does not guarantee an efficient operation of the whole system. In order to achieve higher efficiency and lower...
SWITCH MODE PULSE WIDTH MODULATED DC-DC CONVERTER WITH MULTIPLE POWER TRANSFORMERS
DEFF Research Database (Denmark)
2009-01-01
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......-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....
A digitally controlled PWM/PSM dual-mode DC/DC converter
Institute of Scientific and Technical Information of China (English)
Zhen Shaowei; Zhang Bo; Luo Ping; Hou Sijian; Ye Jingxin; Ma Xiao
2011-01-01
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 μm 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.
Analysis and Controller Design of a Universal Bidirectional DC-DC Converter
Directory of Open Access Journals (Sweden)
Kou-Bin Liu
2016-06-01
Full Text Available In this paper, first the operating principles of a non-isolated universal bidirectional DC-DC converter are studied and analyzed. The presented power converter is capable of operating in all power transferring directions in buck/boost modes. Zero voltage switching can be achieved for all the power switches through proper modulation strategy design, therefore, the presented converter can achieve high efficiency. To further improve the efficiency, the relationship between the phase-shift angle and the overall system efficiency is analyzed in detail, an adaptive phase-shift (APS control method which determines the phase-shift value between gating signals according to the load level is then proposed. As the modulation strategy is a software-based solution, there is no requirement for additional circuits, therefore, it can be implemented easily and instability and noise susceptibility problems can be reduced. To validate the correctness and the effectiveness of the proposed method, a 300 W prototyping circuit is implemented and tested. A low cost dsPIC33FJ16GS502 digital signal controller is adopted in this paper to realize the power flow control, DC-bus voltage regulation and APS control. According to the experimental results, a 12.2% efficiency improvement at light load and 4.0% efficiency improvement at half load can be achieved.
High reliability DC/DC converter module for electronic boards equipped with FPGAs
Viganò, W.; Boccardi, A.; Zamantzas, C.
2015-01-01
The Beam Instrumentation Group at CERN is designing a new general-purpose VME carrier module utilising several PTH04T230W DC/DC converters. These off-the-shelf converters are built with unshielded inductors and need to be mounted on the printed circuit board as stand-alone components. Thus, reducing the global manageability and increasing the total cost of the carrier module. The new design aims to develop a module with better power dissipation, efficiency and reliability. In the future, it should be also possible to be directly integrated on the mainboard. For this reason, a Buck DC/DC converter has been implemented with the following main characteristics: input range from 3.0 V to 5.5 V; output range from 0.6 V to 3.3 V, settable by means of an external resistor; output current protection at 6 A; maximum output ripple ± 50 mVpp; switching frequency of 300KHz; short circuit protection; On/Off function; EMI reduction with frequency spread spectrum; soft-start function and thermal shutdown, in a 16 × 19 mm compact size. The selected buck controller is the TPS40303 integrated circuit and drives the CSD16321 power MOSFET, both from Texas Instruments. All selected components have been used at a minimum derating of 50% to reduce component stress and increase the reliability of this module. The selected inductors, i.e. Bourns SRP1055, are the main contributor for the high efficiency (95%), due to their very low equivalent series resistance. On the 4-layer PCB comprising all the components of this module, a snubber circuit, for further reduction of the output ripple due to the MOSFET ringing, can be mounted optionally. It is left as an option due to its effect on the total efficiency. The board layout has been optimized for maximum heat transfer and it can be used without active cooling. The board can maintain the maximum temperature on its surface, while at maximum current output, below 55°C at 25°C ambient temperature. An example of the electrical performance
High reliability DC/DC converter module for electronic boards equipped with FPGAs
International Nuclear Information System (INIS)
The Beam Instrumentation Group at CERN is designing a new general-purpose VME carrier module utilising several PTH04T230W DC/DC converters. These off-the-shelf converters are built with unshielded inductors and need to be mounted on the printed circuit board as stand-alone components. Thus, reducing the global manageability and increasing the total cost of the carrier module. The new design aims to develop a module with better power dissipation, efficiency and reliability. In the future, it should be also possible to be directly integrated on the mainboard. For this reason, a Buck DC/DC converter has been implemented with the following main characteristics: input range from 3.0 V to 5.5 V; output range from 0.6 V to 3.3 V, settable by means of an external resistor; output current protection at 6 A; maximum output ripple ± 50 mVpp; switching frequency of 300KHz; short circuit protection; On/Off function; EMI reduction with frequency spread spectrum; soft-start function and thermal shutdown, in a 16 × 19 mm compact size. The selected buck controller is the TPS40303 integrated circuit and drives the CSD16321 power MOSFET, both from Texas Instruments. All selected components have been used at a minimum derating of 50% to reduce component stress and increase the reliability of this module. The selected inductors, i.e. Bourns SRP1055, are the main contributor for the high efficiency (95%), due to their very low equivalent series resistance. On the 4-layer PCB comprising all the components of this module, a snubber circuit, for further reduction of the output ripple due to the MOSFET ringing, can be mounted optionally. It is left as an option due to its effect on the total efficiency. The board layout has been optimized for maximum heat transfer and it can be used without active cooling. The board can maintain the maximum temperature on its surface, while at maximum current output, below 55°C at 25°C ambient temperature. An example of the electrical performance
Directory of Open Access Journals (Sweden)
Chih-Lung Shen
2015-09-01
Full Text Available In this paper, an integrated three-voltage-booster DC-DC (direct current to direct current converter is proposed to achieve high voltage gain for renewable-energy generation systems. The proposed converter integrates three voltage-boosters into one power stage, which is composed of an active switch, a coupled-inductor, five diodes, and five capacitors. As compared with conventional high step-up converters, it has a lower component count. In addition, the features of leakage-energy recycling and switching loss reduction can be accomplished for conversion efficiency improvement. While the active switch is turned off, the converter can inherently clamp the voltage across power switch and suppress voltage spikes. Moreover, the reverse-recovery currents of all diodes can be alleviated by leakage inductance. A 200 W prototype operating at 100 kHz switching frequency with 36 V input and 400 V output is implemented to verify the theoretical analysis and to demonstrate the feasibility of the proposed high step-up DC-DC converter.
Adaptive terminal sliding-mode control strategy for DC-DC buck converters.
Komurcugil, Hasan
2012-11-01
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.
Progress on DC-DC Converters for a Silicon Tracker for the sLHC Upgrade
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
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 μm 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...
Fast response double series resonant high-voltage DC-DC converter
Lee, S. S.; Iqbal, S.; Kamarol, M.
2012-10-01
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.
Bifurcation Analysis of a DC-DC Bidirectional Power Converter Operating with Constant Power Loads
Cristiano, Rony; Pagano, Daniel J.; Benadero, Luis; Ponce, Enrique
Direct current (DC) microgrids (MGs) are an emergent option to satisfy new demands for power quality and integration of renewable resources in electrical distribution systems. This work addresses the large-signal stability analysis of a DC-DC bidirectional converter (DBC) connected to a storage device in an islanding MG. This converter is responsible for controlling the balance of power (load demand and generation) under constant power loads (CPLs). In order to control the DC bus voltage through a DBC, we propose a robust sliding mode control (SMC) based on a washout filter. Dynamical systems techniques are exploited to assess the quality of this switching control strategy. In this sense, a bifurcation analysis is performed to study the nonlinear stability of a reduced model of this system. The appearance of different bifurcations when load parameters and control gains are changed is studied in detail. In the specific case of Teixeira Singularity (TS) bifurcation, some experimental results are provided, confirming the mathematical predictions. Both a deeper insight in the dynamic behavior of the controlled system and valuable design criteria are obtained.
Multiphase High-Frequency Isolated DC-DC Converter for Industrial Applications
Maurya, Rakesh; Srivastava, S. P.; Agarwal, Pramod
2014-01-01
Industrial applications such as welding, plasma cutting, and surface hardening require a large DC current at low voltage. In such applications, the rating of power supply varies from few kilowatts to hundreds of kilowatts. The power supply employs in such applications particularly in arc welding process is expected to operate from open-circuit (no-load) to short-circuit (when the electrode sticks to the workpiece for a short span of time) quickly. In this paper, high-frequency isolated multiphase DC-DC converter is proposed which is well suited for aforementioned applications. Based on mathematical analysis, a simulation study with 5 kW, 5 V/1,000 A proposed model is carried out using Simulink block set and Sim Power System tool box and its performances are evaluated under symmetrical control methods. To verify the simulation results, scaled prototype model of rating 1.5 V/100 A is developed and tested with aforementioned control method under different operating conditions. In comparison with conventional welding power supply employed in many industries, the performance of proposed converter is improved significantly in terms of size and weight, efficiency and dynamic response.
Directory of Open Access Journals (Sweden)
Liwen Pan
2016-06-01
Full Text Available This paper presents an on-board vehicular battery charger that integrates bidirectional AC/DC converter and DC/DC converter to achieve high power density for application in electric vehicles (EVs. The integrated charger is able to transfer electrical energy between the battery pack and the electric traction system and to function as an AC/DC battery charger. The integrated charger topology is presented and the design of passive components is discussed. The control schemes are developed for motor drive system and battery-charging system with a power pulsation reduction circuit. Simulation results in MATLAB/Simulink and experiments on a 30-kW motor drive and 3.3-kW AC/DC charging prototype validate the performance of the proposed technology. In addition, power losses, efficiency comparison and thermal stress for the integrated charger are illustrated. The results of the analyses show the validity of the advanced integrated charger for electric vehicles.
Energy Technology Data Exchange (ETDEWEB)
Pledl, Georg; Lutter, Peter [Finepower GmbH, Ismaning (Germany)
2010-07-01
Especially in automotive engineering, the big aim of electronic device development is to combine minimum possible weight, highest efficiency and low electromagnetic interference. Since there is a wide range of energy storage devices and power consumption requirements are very versatile, there are many possible solutions for electronic power devices, but not all of them will be appropriate for each system. One possible solution concerning dc/dc converters is represented by the phase shift operation for full bridge topologies. This procedure is used for supplying the electrical 14 V system from the high voltage energy storage or, in the other direction, charge the HV battery from the 14 V net or even from an external 230 V / 400 ac net. Finepower has developed 2 prototypes for research, which are presented in this contribution. Another new topology, a bidirectional LLC Converter, is presented as well. Energy consumption is growing and the available space for electronic power devices is held very small, so the power density increases and thermal management becomes more difficult. As dimensions of bus bars, semiconductors or inductive components are shrinking, parasitic influence becomes more and more significant. For getting information about function and influence of parasitics of electronic power devices, simulation is a very important tool since it saves much time and gives the possibility to extract internal dimensions of electrical circuits which cannot be measured in reality. (orig.)
Digitally intensive DC-DC converter for extreme space environments Project
National Aeronautics and Space Administration — The Space Micro-Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator core...
Digitally intensive DC-DC converter for extreme space environments Project
National Aeronautics and Space Administration — The Space Micro Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator...
Directory of Open Access Journals (Sweden)
Liao Xiaozhong
2013-02-01
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.
Discrete prediction controller for DC-DC converter - doi: 10.4025/actascitechnol.v36i1.18770
Rengamani Shenbagalakshmi; Thangaswamy Sree Renga Raja
2014-01-01
A discrete controller is designed for low power dc-dc switched mode power supplies. The approach is based on time domain and the control loop continuously and concurrently tunes the compensator parameters to meet the converter specifications. A digital state feedback control combined with the load estimator provides a complete compensation, which further improves the dynamic performance of the closed loop system. Simulation of digitally controlled Buck converter is performed with MATLAB/Simul...
A 1.6-kW, 110-kHz dc-dc converter optimized for IGBT's
Chen, Keming; Stuart, Thomas A.
1993-01-01
A full bridge dc-dc converter using a zero-current and zero-voltage switching technique is described. This circuit utilizes the characteristics of the IGBT to achieve power and frequency combinations that are much higher than previously reported for this device. Experimental results are included for a 1.6-kW, 110-kHz converter with 95 percent efficiency.
qZS-Based Soft-Switching DC/DC Converter with a Series Resonant LC Circuit
Vinnikov, D; Zaķis, J; Liivik, L; Raņķis, I
2013-01-01
This paper discusses further modifications of the recent popular qZS-based DC/DC converter design by the introduction of the resonant LC circuit in series to the primary winding of the isolation transformer. The primary aim is to achieve the zero voltage and zero current switching of transistors. As an additional benefit of the resonant LC circuit, the converter is able to perform the voltage buck function simply by changing the switching frequency of the transistors. The control principle of...
Evaluating neural control with optimal architecture for DC/DC converter
Directory of Open Access Journals (Sweden)
Fredy Hernán Martínez Sarmiento
2010-05-01
-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.
Design of piezoelectric transformer for DC/DC converter with stochastic optimization method
Vasic, Dejan; Vido, Lionel
2016-04-01
Piezoelectric transformers were adopted in recent year due to their many inherent advantages such as safety, no EMI problem, low housing profile, and high power density, etc. The characteristics of the piezoelectric transformers are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converters, there are non-linear electronic circuits connected before and after the transformer. Consequently, the output load is variable and due to the output capacitance of the transformer the optimal working point change. This paper starts from modeling a piezoelectric transformer connected to a full wave rectifier in order to discuss the design constraints and configuration of the transformer. The optimization method adopted here use the MOPSO algorithm (Multiple Objective Particle Swarm Optimization). We start with the formulation of the objective function and constraints; then the results give different sizes of the transformer and the characteristics. In other word, this method is looking for a best size of the transformer for optimal efficiency condition that is suitable for variable load. Furthermore, the size and the efficiency are found to be a trade-off. This paper proposes the completed design procedure to find the minimum size of PT in need. The completed design procedure is discussed by a given specification. The PT derived from the proposed design procedure can guarantee both good efficiency and enough range for load variation.
Total ionizing dose effects of DC-DC power converter used in satellite
International Nuclear Information System (INIS)
The total ionizing dose effects and annealing effects of DVHF2812DF and DVTR2815DF DC-DC power converters were investigated. The typical electrical parameters, such as input current, output current, output voltage, and input current of inhibition mode, as functions of the total dose with different loads and different input voltages were discussed. The relationships between these parameters and the annealing time were observed. The experiment results show that when annealing at room temperature, the trapped holes in deeper energy levels anneal little, which results in dramatic changes of the electric parameters of the DVHF2812DF device when irradiated with extra dose irradiation. However, these parameters go back to the initial values when annealing at high temperature. There are more changes of the electric parameters under the full power loaded situation than other conditions. The input current under inhibition mode can be considered as a sensitive parameter in the evaluation of the radiation-hardened levels of the devices. (authors)
Closed loop control of ZVS half bridge DC-DC converter with DCS PWM Control
Directory of Open Access Journals (Sweden)
JANAPATI SIVAVARA PRASAD
2012-10-01
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.
Energy Technology Data Exchange (ETDEWEB)
Natsheh, Ammar N.; Kettleborough, J. Gordon [Department of Electronic and Electrical Engineering, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom); Nazzal, Jamal M. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan)], E-mail: jnazzal@ammanu.edu.jo
2009-03-15
The paper describes an experimental study of the bifurcation behaviour of a modular peak current-mode controlled DC-DC boost converter. The parallel-input/parallel-output converter comprises two identical boost circuits and operates in the continuous-current conduction mode. A comparison is made between the results obtained from an experimental converter with those obtained from bifurcation diagrams generated from previous work and waveforms from a new MATLAB/SIMULINK simulation presented in this paper. Another comparison is made between the modular converter diagrams with those of the single boost converter.
Energy Technology Data Exchange (ETDEWEB)
Vaisanen, V.
2012-07-01
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
Energy Conversion Module (ECM) - DC/DC converter with integrated supercaps
Energy Technology Data Exchange (ETDEWEB)
Ollhaeuser, Helmut [ALCOA/AFL Europe GmbH (Germany)
2008-07-01
In the light of increasing hybridization of future vehicle generations mainly those functionalities will be realized which contribute to fuel- and at the end emission-reduction. Recuperation, Start-Stop, E-steering and EDS-stabilization therefore constitute applications for which an efficient energy management has to be provided In this context ALCOA / AFL Europe GmbH developed a patent pending system solution, by which in one single unit a powerful DC/DC converter is integrated with the storage medium EDLC or Super-/Ultracap - on the one hand the restrictive packaging and on the other hand high performance requirements of the OEM can be met in a high degree. Possible issues arising from the compact integration of the supercaps such as heat dissipation and EMI are solved in a unique way - even the impacts in case of a defect cell are eliminated by a sophisticated balancing. The main performance characteristics of the current finished 1 KW solution being in test operation at various OEM are: - Output: 1 KW bidirectional - Capacity: 29,8 F / 12 Cells a 350 F - Additional fused power output - Optional output for consumers during motor start - Protection class IP 6K7 - Buck/Boost converter 2-phases - Operating frequency 125 kHz - Current control and phase monitoring realized in HW With its scaleable approach and the possibility to be integrated rapidly and cost-efficient in new carlines, the ECM just today combines the advantages of an intelligent electric power management. New prospective application-ranges - i.e. up to 5 KW for commercial vehicles and/or buses - are right now under development and clear its way for series implementation, soon. (orig.)
Directory of Open Access Journals (Sweden)
Muh. Zakiyullah Romdlony
2012-07-01
Full Text Available Well-regulated DC bus voltage is the important point to guarantee the power demand in hybrid vehicle applications. Voltage regulation can be achieved with control method that build switching signal on DC-DC converter. This paper describes design and small scale experimental results of bus voltage regulation control of the DC-DC bidirectional converter with battery and supercapacitor as energy source. The control system consists of two control loops, the outer loop that get DC bus voltage feedback using PI anti-windup back calculation control method. This outer loop will generate a reference current for the inner loop that implement hysteresis control. The inner control loop will compare that reference curent with the source current obtained from the current sensor. Simulation and experimental results show that bus voltage is well-regulated under the load changes with 1% voltage ripple.
Integrated modeling and control of a PEM fuel cell power system with a PWM DC/DC converter
Energy Technology Data Exchange (ETDEWEB)
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
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)
Directory of Open Access Journals (Sweden)
Haojie Wang
2016-07-01
Full Text Available It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC is proposed for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.
Integrated modeling and control of a PEM fuel cell power system with a PWM DC/DC converter
Choe, Song-Yul; Lee, Jung-Gi; Ahn, Jong-Woo; Baek, Soo-Hyun
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.
Iwens, R. P.; Lee, F. C.; Triner, J. E.
1977-01-01
Using discrete time state variable representation, a generalized computer-aided modeling and analysis of dc-dc converters is presented. The methodology provides exact modeling and is applicable to all types of power stages and duty-cycle control, including continuous and discontinuous inductor current operation. Converter stability, transient behavior and audio susceptibility can be analytically evaluated and predicted. The generalized theory of the proposed approach to converter modeling and analysis is presented first, followed by a demonstrative example applying the theory to a constant frequency buck converter operating in continuous and discontinuous inductor current mode. Excellent agreement with laboratory test data has been observed.
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.; Maksimovic, Dragan; Sarban, Rahimullah
2014-01-01
This paper presents the design of a low input (24 V) and variable high output voltage (0-2.5 kV) bidirectional dc-dc converter for driving a capacitive actuator. The topology is a digitally controlled bidirectional flyback converter with a variable frequency control. The objective is, to design the converter for efficiently charging and discharging the capacitive actuator from 0 V to 2.5 kV and vice versa, respectively. The converter is used to drive a dielectric electro active polymer (DEAP)...
Using Nyquist or Nyquist-Like Plot to Predict Three Typical Instabilities in DC-DC Converters
Fang, Chung-Chieh
2012-01-01
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...
A brief review of models of DC-DC power electronic converters for analysis of their stability
Siewniak, Piotr; Grzesik, Bogusław
2014-10-01
A brief review of models of DC-DC power electronic converters (PECs) is presented in this paper. It contains the most popular, continuous-time and discrete-time models used for PEC simulation, design, stability analysis and other applications. Both large-signal and small-signal models are considered. Special attention is paid to models that are used in practice for the analysis of the global and local stability of PECs.
Design and control of a bidirectional dc/dc converter for an electric vehicle application.
Albiol Tendillo, Laura
2015-01-01
L’objectiu d’aquesta tesi és desenvolupar una solució pel convertidor DC/DC del sistema de tracció d’un vehicle elèctric. Varis aspectes d’aquesta solució han estat examinats minuciosament. El primer és la tria de la topologia de convertidor DC/DC bidireccional apropiada, tenint en compte l’aplicació considerada. Finalment s’ha optat per un convertidor boost bidireccional amb filtre de sortida. Un cop determinada la topologia, s’ha analitzat l’estabilitat del sistema, tenint en compte que l’a...
Quasi-Periodicity, Chaos and Coexistence in the Time Delay Controlled Two-Cell DC-DC Buck Converter
Koubaâ, Karama; Feki, Moez
In addition to border collision bifurcation, the time delay controlled two-cell DC/DC buck converter is shown to exhibit a chaotic behavior as well. The time delay controller adds new design parameters to the system and therefore the variation of a parameter may lead to different types of bifurcation. In this work, we present a thorough analysis of different scenarios leading to bifurcation and chaos. We show that the time delay controlled two-cell DC/DC buck converter may also exhibit a Neimark-Sacker bifurcation which for some parameter set may lead to a 2D torus that may then break yielding a chaotic behavior. Besides, the saturation of the controller can also lead to the coexistence of a stable focus and a chaotic attractor. The results are presented using numerical simulation of a discrete map of the two-cell DC/DC buck converter obtained by expressing successive crossings of Poincaré section in terms of each other.
Directory of Open Access Journals (Sweden)
Ahteshamul Haque
2016-02-01
Full Text Available The energy crisis concern leads to look for alternate source of energy. Solar energy is considered as most reliable among the all renewable energy sources. Solar PV (Photovoltaic is used to convert solar energy into electric energy. The efficiency of solar PV is very low and its characteristic is nonlinear. To overcome these drawbacks a technique known as maximum power point tracking is used. This algorithm is implemented in the control circuit of DC – DC converter. The objective of this paper is to evaluate the MPPT (Maximum Power Point Tracking with buck DC-DC converter under load varying conditions. The simulation work is done using PSIM simulation software.
Modeling and Control of DC/DC Boost Converter using K-Factor Control for MPPT of Solar PV System
DEFF Research Database (Denmark)
Vangari, Adithya; Haribabu, Divyanagalakshmi; Sakamuri, Jayachandra N.
2015-01-01
is presented. Design of the passive elements of the boost converter as per the system specifications is also illustrated. The performance of the proposed K factor control method is verified with the simulations for MPPT on solar PV system at different atmospheric conditions. A new circuit based model for solar......This paper is focused on the design of a controller for the DC/DC boost converter using K factor control, which is based on modified PI control method, for maximum power point tracking (MPPT) of solar PV system. A mathematical model for boost converter based on small signal averaging approach...
Current-Fed Step-up DC/DC Converter for Fuel Cell Applications with Active Overvoltage Clamping
Andreičiks, A; Steiks, I; Krievs, O
2010-01-01
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 investi...
George, Libin; Gargiulo, Gaetano Dario; Lehmann, Torsten; Hamilton, Tara Julia
2016-06-01
This paper presents the design of a reconfigurable buck-boost switched-capacitor DC-DC converter suitable for use in a wide range of biomedical implants. The proposed converter has an extremely small footprint and uses a novel control method that allows coarse and fine control of the output voltage. The converter uses adaptive gain control, discrete frequency scaling and pulse-skipping schemes to regulate the power delivered to a range of output voltages and loads. Adaptive gain control is used to implement variable switching gain ratios from a reconfigurable power stage and thereby make coarse steps in output voltage. A discrete frequency scaling controller makes discrete changes in switching frequency to vary the power delivered to the load and perform fine tuning when the output voltage is within 10% of the target output voltage. The control architecture is predominately digital and it has been implemented as part of a fully-integrated switched-capacitor converter design using a standard bulk CMOS 0.18 μm process. Measured results show that the converter has an output voltage range of 1.0 to 2.2 V, can deliver up to 7.5 mW of load power and efficiency up to 75% using an active area of only 0.04 mm (2), which is significantly smaller than that of other designs. This low-area, low-complexity reconfigurable power converter can support low-power circuits in biomedical implant applications. PMID:26600247
George, Libin; Gargiulo, Gaetano Dario; Lehmann, Torsten; Hamilton, Tara Julia
2016-06-01
This paper presents the design of a reconfigurable buck-boost switched-capacitor DC-DC converter suitable for use in a wide range of biomedical implants. The proposed converter has an extremely small footprint and uses a novel control method that allows coarse and fine control of the output voltage. The converter uses adaptive gain control, discrete frequency scaling and pulse-skipping schemes to regulate the power delivered to a range of output voltages and loads. Adaptive gain control is used to implement variable switching gain ratios from a reconfigurable power stage and thereby make coarse steps in output voltage. A discrete frequency scaling controller makes discrete changes in switching frequency to vary the power delivered to the load and perform fine tuning when the output voltage is within 10% of the target output voltage. The control architecture is predominately digital and it has been implemented as part of a fully-integrated switched-capacitor converter design using a standard bulk CMOS 0.18 μm process. Measured results show that the converter has an output voltage range of 1.0 to 2.2 V, can deliver up to 7.5 mW of load power and efficiency up to 75% using an active area of only 0.04 mm (2), which is significantly smaller than that of other designs. This low-area, low-complexity reconfigurable power converter can support low-power circuits in biomedical implant applications.
Discrete prediction controller for DC-DC converter - doi: 10.4025/actascitechnol.v36i1.18770
Directory of Open Access Journals (Sweden)
Rengamani Shenbagalakshmi
2014-01-01
Full Text Available A discrete controller is designed for low power dc-dc switched mode power supplies. The approach is based on time domain and the control loop continuously and concurrently tunes the compensator parameters to meet the converter specifications. A digital state feedback control combined with the load estimator provides a complete compensation, which further improves the dynamic performance of the closed loop system. Simulation of digitally controlled Buck converter is performed with MATLAB/Simulink. Experimental results are given to demonstrate the effectiveness of the controller using LabVIEW with a data acquisition card (model DAQ Pad - 6009.
Directory of Open Access Journals (Sweden)
Kawa Adam
2014-09-01
Full Text Available The paper treats about main problems of one phase DC-AC microinverters that allow single solar cell to be joined with the grid. One of the issues is to achieve high voltage gain with high efficiency in DC circuit, which is necessary for proper operation of inverter. The operating principles, results of practical implementation and investigations on boost-flyback converter, which meets mentioned demands, are presented. (high step-up DC-DC boost-flyback converter for single phase grid microinverter
ZVS Full-Bridge Based DC-DC Converter with Linear Voltage Gain According to Duty Cycle
Do, Hyun-Lark
2013-09-01
This paper presents a zero-voltage-switching (ZVS) full-bridge based DC-DC converter with linear voltage gain according to duty cycle. The proposed converter is based on an asymmetrical pulse-width-modulation (APWM) full-bridge converter which has various advantages over other converters. However, it has some drawbacks such as limited maximum duty cycle to 0.5 and narrow input range. The proposed converter overcomes these problems. The duty cycle is not limited and input voltage range is wide. Also, the ZVS operation of all power switches is achieved. Therefore, switching losses are significantly reduced and high-efficiency is obtained. Steady-state analysis and experimental results for the proposed converter are presented to validate the feasibility and the performance of the proposed converter.
Topology investigation of front end DC/DC converter for distributed power system
Yang, Bo
2003-01-01
Topology Investigation of Front End DC/DC Power Conversion for Distributed Power System by Bo Yang Fred C. Lee, Chairman Electrical Engineering (Abstract) With the fast advance in VLSI technology, smaller, more powerful digital system is available. It requires power supply with higher power density, lower profile and higher efficiency. PWM topologies have been widely used for this application. Unfortunately, hold up time requirement put huge penalties on the performance o...
Integrated Solar Power Converters: Wafer-Level Sub-Module Integrated DC/DC Converter
Energy Technology Data Exchange (ETDEWEB)
None
2012-02-09
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.
Open-circuit fault detection and tolerant operation for a parallel-connected SAB DC-DC converter
DEFF Research Database (Denmark)
Park, Kiwoo; Chen, Zhe
2014-01-01
This paper presents an open-circuit fault detection method and its tolerant control strategy for a Parallel-Connected Single Active Bridge (PCSAB) dc-dc converter. The structural and operational characteristics of the PCSAB converter lead to several advantages especially for high power applications....... By paralleling modular converters, the power and current ratings of each modular converter can be lowered and by interleaving the switching patterns, the input and output current ripples can be significantly reduced without increasing switching losses or device stresses. Apart from these, the PCSAB converter...... also possesses better reliability under a certain open-circuit fault condition. The proposed fault diagnosis method identifies both location and type of a fault using one current sensor in the output. Depending on the type of the fault, the proposed fault-tolerant strategy tries to keep the capability...
Fuentes, C; Michelis, S; Blanchot, G; Allongue, B; Faccio, F; Orlandi, S; Kayal, M; Pontt, J
2011-01-01
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.
Energy Technology Data Exchange (ETDEWEB)
Fernandez, Luis M., E-mail: luis.fernandez@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Pablo, E-mail: pablo.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Garcia, Carlos Andres, E-mail: carlosandres.garcia@uca.e [Department of Electrical Engineering, EPS Algeciras, University of Cadiz, Avda. Ramon Puyol, s/n. 11202 Algeciras (Cadiz) (Spain); Jurado, Francisco, E-mail: fjurado@ujaen.e [Department of Electrical Engineering, EPS Linares, University of Jaen, C/Alfonso X, No. 28. 23700 Linares (Jaen) (Spain)
2011-05-15
Research highlights: {yields} Hybrid electric power system for a real surface tramway. {yields} Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. {yields} New control strategy for the energy management of the tramway. {yields} Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.
V. V. Subrahmanya Kumar Bhajana; S. Rama Reddy
2010-01-01
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.
Directory of Open Access Journals (Sweden)
V. V. Subrahmanya Kumar Bhajana
2010-08-01
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.
Bifurcation and chaos in multi-parallel-connected current-mode controlled boost DC-DC converters
Institute of Scientific and Technical Information of China (English)
CHEN Ming-liang; MA Wei-ming
2006-01-01
This paper studied the bifurcation and chaos phenomenon in a multi-parallel-connected current-mode controlled boost DC-DC converter system with the use of nonlinear mapping bifurcation theory of two dimensions,and the changing rules of the bifurcation charts with the increase of the control parallels and control parameters were concluded.The method of discrete mapping modeling was utilized to construct the difference equations of the system operating in continuous conduction mode (CCM).Analyses and computer emulations were made.
Ohnishi, Yoshihiro; Ikemoto, Takahiro; Yamamoto, Toru
This paper proposes an adaptive PID controller which is driven by current control performance. The calculations of the PID parameters are based on the generalized minimum variance control(GMVC) algorithm. The current control performance is obtained in an online manner over a user-specified time-window with some overlap. The retuning of PID parameters are only carried out when controller performance deteriorates below a user-specified threshold. Experimental evaluations on the voltage control of the DC-DC converter demonstrates the practicality and utility of this idea.
Application of Multi-port Bidirectional DC-DC Converter to Fuel Cell Vehicle Driving in JC08 Mode
Tanaka, Katsunori; Katayama, Noboru; Kogoshi, Sumio; Fukada, Takafumi; Ogawa, Makoto
A fuel cell-EDLC hybrid power system with a multi-port bidirectional DC-DC converter has been recently proposed for extending lifetime of a fuel cell due to smoothing the output current of the fuel cell. This paper studies the performance of the hybrid power system when a fuel cell vehicle drives in the JC08 mode using a simulation model. The simulation results indicate that even if the load current fluctuates, the output current of the fuel cell could be maintained at almost constant values with an assist from the EDLC although small spikes are observed.
Directory of Open Access Journals (Sweden)
A.S. Oshaba
2013-05-01
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.
Multiphase Isolated DC-DC Converters for Low-Voltage High-Power Fuel Cell Applications
Moon, Seung-Ryul
2007-01-01
Fuel cells provide a clean and highly efficient energy source for power generation; however, in order to efficiently utilize the energy from fuel cells, a power conditioning system is required. Typical fuel cell systems for stand-alone and utility grid-tied stationary power applications are found mostly with low nominal output voltages around 24 V and 48 V, and power levels are found to be 3 to 10 kW [1][2]. A power conditioning system for such applications generally consists of a dc-dc con...
Current-fed Step-up DC/DC Converter for Fuel Cell Applications with Active Overvoltage Clamping
Andreiciks, Aleksandrs; Steiks, Ingars; Krievs, Oskars
2010-01-01
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.
High performance dc-dc conversion with voltage multipliers
Harrigill, W. T.; Myers, I. T.
1974-01-01
The voltage multipliers using capacitors and diodes first developed by Cockcroft and Walton in 1932 were reexamined in terms of state of the art fast switching transistors and diodes, and high energy density capacitors. Because of component improvements, the voltage multiplier, used without a transformer, now appears superior in weight to systems now in use for dc-dc conversion. An experimental 100-watt 1000-volt dc-dc converter operating at 100 kHz was built, with a component weight of about 1 kg/kW. Calculated and measured values of output voltage and efficiency agreed within experimental error.
Directory of Open Access Journals (Sweden)
Boumediène Allaoua
2013-01-01
Full Text Available The development of electric vehicles power electronics system control comprising of DC-AC inverters and DC-DC converters takes a great interest of researchers in the modern industry. A DC-AC inverter supplies the high power electric vehicle motors torques of the propulsion system and utility loads, whereas a DC-DC converter supplies conventional low-power, low-voltage loads. However, the need for high power bidirectional DC-DC converters in future electric vehicles has led to the development of many new topologies of DC-DC converters. Nonlinear control of power converters is an active area of research in the fields of power electronics. This paper focuses on a fuzzy sliding mode strategy (FSMS as a control strategy for boost DC-DC converter power supply for electric vehicle. The proposed fuzzy controller specifies changes in the control signal based on the surface and the surface change knowledge to satisfy the sliding mode stability and attraction conditions. The performances of the proposed fuzzy sliding controller are compared to those obtained by a classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variation of the load resistance and the input voltage of the studied converter.
Transient Performance Improvement Circuit (TPIC)s for DC-DC converter applications
Lim, Sungkeun
of the slow inductor current slew rate which is determined by the input voltage, output voltage, and the inductance. The remaining inductor current in the power delivery path will charge the output capacitors and develop a voltage across the ESR. As a result, large output voltage spikes occur during load current transients. Due to their limited control bandwidth, traditional VRs can not sufficiently respond rapidly to certain load transients. As a result, a large output voltage spike can occur during load transients, hence requiring a large amount of bulk capacitance to decouple the VR from the load [2]. If the remaining inductor current is removed from the power stage or the inductor current slew rate is changed, the output voltage spikes can be clamped, allowing the output capacitance to be reduced. A new design methodology for a Transient Performance Improvement Circuit(TPIC) based on controlling the output impedance of a regulator is presented. The TPIC works in parallel with a voltage regulator (VR)'s ceramic capacitors to achieve faster voltage regulation without the need for a large bulk capacitance, and can serve as a replacement for bulk capacitors. The specific function of the TPIC is to mimic the behavior of the bulk capacitance in a traditional VRM by sinking and sourcing large currents during transients, allowing the VR to respond quickly to current transients without the need for a large bulk capacitance. This will allow fast transient response without the need for a large bulk capacitor. The main challenge in applying the TPIC is creating a design which will not interfere with VR operation. A TPIC for a 4 Switch Buck-Boost (4SBB) converter is presented which functions by con- trolling the inductor current slew rate during load current transients. By increasing the inductor current slew rate, the remaining inductor current can be removed from the 4SBB power delivery path and the output voltage spike can be clamped. A second TPIC is presented which is
DEFF Research Database (Denmark)
Török, Lajos; Munk-Nielsen, Stig
2011-01-01
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...
DEFF Research Database (Denmark)
Park, Kiwoo; Chen, Zhe
2013-01-01
This paper presents a parallel-connected Single Active Bridge (SAB) dc-dc converter for high-power applications. Paralleling lower-power converters can lower the current rating of each modular converter and interleaving the outputs can significantly reduce the magnitudes of input and output current...
DC/DC开关变换器混沌现象研究综述%Summary of the Research on Chaos Phenomena of DC/DC Converter
Institute of Scientific and Technical Information of China (English)
蔚洋; 冯平
2012-01-01
DC/DC功率开关变换器是开关电源的核心部分,通过对其混沌现象的研究可以更加深刻地认识DC/DC变换器的本质,也会在将来基于混沌现象提出新的设计方法和控制策略,实现现有DC/DC变换器无法达到的性能.本文介绍了DC/DC变换器混沌现象的研究现状,对DC/DC变换器混沌现象的基本建模方法进行了综合对比分析,展望了DC/DC变换器混沌研究的发展和未来应用前景.%DC/DC power switch converter is the core part of switch power supply. Through the study of chaos phenomena, the essence of DC/DC converter can be more deeply understand, the new design methods and control strategies based on chaos phenomena will be put forward in the future, to achieve the existing DC/DC converter that cannot reach. This paper introduces the research status of the DC/DC converter chaos phenomena, makes comprehensive comparative analysis of the basic modeling method of DC/DC converter chaos phenomena, and looks to its development and future application prospect.
Directory of Open Access Journals (Sweden)
1V.Chaitanya,P.G.scholar,
2015-10-01
Full Text Available : Even though electrical vehicle concept is introduced in early 1800’s, it gained importance in past couple of decades due to growing conscience on environmental aspects. Different types of electrical vehicles are manufactured in the past centuries and now onboard generation is seems to be promising by fulfilling the needs of a vehicle. Fuel cells or fuel cell stack produces typically 32-68V of EMF, which has to be conditioned before it fed to motor. The conditioning involves two stages DCDC conversion and then to DC-AC conversion .DC-AC conversion is done through inverter. For DC-DC to conversion various topologies are proposed such as fly back, forward, buck-boost are proposed. This paper deals with the front end DC-DC converter and inverter switching. A hybrid modulation scheme is used to produce pulses to switch the source end full bridge rectifier and inverter at load end. In this modulation scheme high frequency pulses given to full bridge rectifier and 33% modulation scheme based pulses are produced for inverter switching.
SUPPRESSING CONDUCTED EMI FROM A DC/DC HIGH POWER CONVERTER BASED ON MIXED-MODE FILTER
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
Conducted electromagnetic interference (EMI) from a 7.5kVA DC/DC high power converter is investigated to agree with EN class A. Here in some passive methods of suppressing conducted EM Noise, such as mixed-mode (MM) EMI filters, snubbing circuits and other means, are used. Based on measurement, the sources of noise are detected with the characteristics analyzed in detail. The MM EMI filters is valuable means with which low-frequency part and some of the high frequency part of conducted EM Noise can be efficiently reduced. How to lay out the MM filters on both sides of the converter is outlined in detail. In addition, multiple grounding and RDC snubbing circuits are employed to improve the performance in high frequency. The experimental results confirm the methods adopted.
Simple digital PWM and PSM controlled DC-DC boost converter for luminance-regulated WLED driver
Institute of Scientific and Technical Information of China (English)
LIU Xin; GUO Shu-xu; CHANG Yu-chun; ZHU Shun-dong; WANG Shuai
2009-01-01
This article presents a control strategy based on simple digital pulse-width modulation (DPWM) and pulse-skip modulation (PSM) for a DC-DC boost converter, to drive a luminance-regulated white light emitting diodes (WLEDs). The presented control strategy not only retains most of the advantages and flexibilities of traditional digital PWM, but also reduces complexity and cost. Based on analyzing the principle of the presented control strategy, the white light emitting diode (WLED) driver is designed and simulated using the 0.6 (m CMOS process. Simulation results of the boost converter show that the power efficiency is above 76% for a full load, with a peak efficiency of 88% when supply voltage varies from 2.7 V to 5.5 V. The control strategy overcomes low efficiency for PWM mode with light load.
Directory of Open Access Journals (Sweden)
Yigeng Huangfu
2016-06-01
Full Text Available This paper aims to focus on the smooth output of DC-DC buck converters in wireless power transfer systems under input perturbations and load disturbances using the high-order sliding mode controller (HOSM and HOSM with super-twisting differentiator (HOSM + STD. The proposed control approach needs only measurement of converter output voltage. Theoretical analysis and design procedures, as well as the super-twisting differentiator of the proposed controller are presented in detail with the prescribed convergence law of high-order sliding modes. Comparisons of both simulation and experimental results among conventional proportional-integral (PI control, traditional sliding mode control (SMC, HOSM and HOSM + STD under various test conditions such as steady state, input voltage perturbations and output load disturbances, are presented and discussed. The results demonstrate and validate the effectiveness and robustness of the proposed control method.
Energy Technology Data Exchange (ETDEWEB)
Floettmann, B.; Weghaus, L.; Schoellmann, M. [Hella KGaA Hueck und Co., Lippstadt (Germany)
2007-07-01
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.)
Energy Technology Data Exchange (ETDEWEB)
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
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)
三重交错并联DC／DC变换器设计%Design of a triple interleaving DC/DC converter of composite power electric cars
Institute of Scientific and Technical Information of China (English)
张智林; 张彦会; 张群
2012-01-01
DC／DC变换器是复合电源电动汽车的重要组成部分之一，为了提高DC／DC变换器的功率密度，DC／DC变换器正在向高频化发展，研究在单相DC／DC变换器的基础上，设计了一种三重交错并联DC／DC变换器，可以提高系统的开关频率、降低纹波电压，从而减小滤波器的体积、提高功率密度．最后通过Simulink进仿真分析，结果表明：三重交错并联DC／DC变换器的纹波电压明显小于单相DC／DC变换器，有利于功率密度的提高．%DC/DC converter is the important part of composite power electric cars. In order to improve the power density of DC/DC converter, high frequency is required. This paper designs a triple inter/earing DC/DC converter based on the single phase DC/DC converter. It can reduce the ripple voltage effectively, reduce the volume of the filter and improve the switch frequency of the system. Finally, through the simulation analysis, the results show that the system efficiency of the triple interleaving DC/DC converter is better than the single phase DC/DC converter, thus the power density is increased.
Quasi-Periodicity and Border-Collision Bifurcations in a DC-DC Converter with Pulsewidth Modulation
DEFF Research Database (Denmark)
Zhusubalaliyev, Zh. T.; Soukhoterin, E.A.; Mosekilde, Erik
2003-01-01
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....
Optimizing the dynamics of a two-cell DC-DC buck converter by time delayed feedback control
Feki, M.; El Aroudi, A.; Robert, B. G. M.; Martínez-Salamero, L.
2011-11-01
A study of the dynamical behavior of a two-cell DC-DC buck converter under a digital time delayed feedback control (TDFC) is presented. Various numerical simulations and dynamical aspects of this system are illustrated in the time domain and in the parameter space. Without TDFC, the system may present many undesirable behaviors such as sub-harmonics and chaotic oscillations. TDFC is able to widen the stability range of the system. Optimum values of parameters giving rise to fast response while maintaining stable periodic behavior are given in closed form. However, it is detected that in a certain region of the parameter space, the stabilized periodic orbit may coexist with a chaotic attractor. Boundary between basins of attraction are obtained by means of numerical simulations.
Faccio, F; Michelis, S; Faccio, Federico; Fuentes, C; Allongue, B; Sorge, R; Orlandi, S
2010-01-01
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.
Shimer, Daniel W.; Lange, Arnold C.
1995-01-01
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.
International Nuclear Information System (INIS)
In this paper, we propose a new design procedure to determine the optimal size of a piezoelectric transformer (PT) for DC/DC converter applications. We examined several parameters, which allows us to produce a piezoelectric transformer with optimal efficiency and which has an optimal range for regulating voltage. The characteristics of a piezoelectric transformer (PT) are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converter applications, it requires the presence of a rectifier circuit block. A rectifier is usually a nonlinear device which does not act like a pure resistor. We began by modeling a full-wave rectifier directly in order to understand the design constraint variables such as the maximum mechanical current, the piezoelectric transformer configuration, and the energy balance of the PT configuration. In our final design, a stacked disk-type piezoelectric transformer with radial-mode vibration was chosen due to the large number of design parameters required. In our new design procedure, instead of just looking at the typical optimal loading condition of the PT, we used the concept of a maximum mechanical current to determine the new optimal efficiency which is suitable for voltage regulation. From our results we found that the size of the piezoelectric transformer and efficiency are trade-offs which means that they have an inverse relationship. In summary, we developed a new design procedure to determine the optimal size of a piezoelectric transformer, which we found to be small but with high efficiency so as to provide an optimal range for regulating voltage
M.K. Kazimierczuk; R.S. Geise; A. Reatti
1995-01-01
An extensive small-signal analysis of a single-loop voltage mode-control strategy for a pulse-width-modulated (PWM) boost DC-DC power converter operating in continuous conduction mode (CCM) is proposed using a new nonsymmetric phase controller. To model the boost power stage, a linear circuit model is used which includes all parasitic components such as the equivalent series resistance (ESR) of the filter capacitor, the ESR of the inductor, the transistor ON-resistance, and the diode forward ...
Magnetically coupled high-gain Y-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede;
2014-01-01
-pull circuit with voltage-doubling rectification. The converter's voltage gain is presently not matched by any other converter operating at the same switch duty ratio. The converter also has more degrees of freedom in design for setting the desired gain than other converters, and hence can better meet...
Stability analysis of a high-step-Up DC grid-connected two-stage boost DC-DC converter
Directory of Open Access Journals (Sweden)
El Aroudi A.
2014-01-01
Full Text Available High conversion ratio switching converters are used whenever there is a need to step-up dc source voltage level to a much higher output dc voltage level such as in photovoltaic systems, telecommunications and in some medical applications. A simple solution for achieving this high conversion ratio is by cascading different stages of dc-dc boost converters. The individual converters in such a cascaded system are usually designed separately applying classical design criteria. However these criteria may not be applicable for the complete cascaded system . This paper first presents a glimpse on the bifurcation behavior that a cascade connection of two boost converters can exhibit. It is shown that the desired periodic orbit can undergo period doubling leading to subharmonic oscillations and chaotic regimes. Then, in order to simplify the analysis the second stage is considered as constant current sink and design-oriented analysis is carried out to obtain stability boundaries in the parameter space by taking into account slope interactions between the state variables in the two-different stages.
Two-output Class E Isolated dc-dc Converter at 5 MHz Switching Frequency
Pavlovic, Zoran; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; García Suárez, Oscar; Prieto López, Roberto; Cobos Márquez, José Antonio
2010-01-01
This paper presents a two output class-E isolated dcdc converter that regulates the output voltages at fixed switching frequency. The converter is simulated at operating frequency of 5 MHz. The converter output power is 40 W and the output voltages are 15 V and 5 V. All the switches operate at zero voltage switching (ZVS) conditions for the full load range. The circuit configuration is simple with small passive components which reduce the size of the converter. The circuit also has ...
A novel resonant transition push-pull DC-DC converter
Swaminathan, B.; Ramanarayanan, V
2004-01-01
In hard-switched converters, the switching frequency is limited by switching losses and EMI problems. However, high-switching frequency is necessary to reduce the converter size. Hence, soft switching is imperative at high switching frequency to obtain good efficiency. Push-pull converter is a preferred topology at medium power level. This paper proposes a novel resonant transition topology for push-pull converter. The proposed topology uses two additional switches and two diodes when compare...
New DC/DC High Step Up Isolated Converter with ZVS
Directory of Open Access Journals (Sweden)
Ehsan Movahedi
2014-10-01
Full Text Available In this paper we presents a soft switch sepic, flyback converter. At first the converter have hard switching in main switch and completely analysis then added auxiliary circuit for soft switching Auxiliary circuit in the converter is not only soft switching condition for the main switch but also prevents the spike voltage across the main switch when turned off that because leakage inductance. Therefore, the proposed converter efficiency in comparison with the previous converters increased and voltage stress on the main switch is reduced. Also the auxiliary switch in the converter have soft switching and thereby decrese losses. this converter Control with pwm.These converter have higher efficiency than the similar converters and the cost is low. Auxiliary circuit in the converter is not only soft switching condition for the main switch but also prevents the spike voltage across the main switch when turned off that because leakage inductance. Therefore, the proposed converter efficiency in comparison with the previous converters increased and voltage stress on the main switch is reduced.
Self-oscillating Galvanic Isolated Bidirectional Very High Frequency DC-DC Converter
DEFF Research Database (Denmark)
Pedersen, Jeppe Arnsdorf; Madsen, Mickey Pierre; Knott, Arnold;
2015-01-01
This paper describes a galvanic isolated bidirectional Very High Frequency (VHF = 30 MHz - 300MHz) ClassE converter. The reason for increasing the switching frequency is to minimize the passive components in the converter. To make the converter topology bidirectional the rectifier has to be synch...
Modular DC-DC converter system for energy harvesting with EAPs
Eitzen, L.; Graf, C.; Maas, J.
2013-04-01
Energy harvesting with EAPs requires an energy-efficient power electronics providing a bidirectional energy transfer and operating voltages of up to several kilovolts. A possibility to achieve a high energy-efficiency for high voltage conversion is the use of a modular converter system consisting of several bidirectional converter modules, which are connected in series on the converter output side and in parallel at the input side. Since each converter stage provides only a part of the overall converter output voltage, the converter module output voltages can effectively be reduced by choosing the number of cascaded converter modules appropriately. This allows the use of standard semiconductor switches with superior electrical characteristics compared to high voltage semiconductors, enabling a high energy-efficiency and smaller passive components. Since EAP devices exhibit a mainly capacitive behavior and a limitation of the operating current is required for electrode protection, the utilized converter structure/topology has to be operated as a controllable current source on the lowest control level, which is achieved by operating the converter modules of the modular converter system with a subordinate closed-looped current control scheme. In order to avoid voltage unbalances among the single converter modules, a method for voltage balancing is presented. For validation, experimental results of a realized bidirectional flyback converter prototype are presented and discussed.
A New Soft Switching Current fed DC-DC Converter for Medium Power Applications
Majid Delshad
2008-01-01
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 con...
Isolated DC-DC UPS based in a forward-forward converter analysis and design
García Suárez, Oscar; Flores Oropeza, Luis Alejandro; Román Loera, Alejandro; Esparza González, Mario S.
2008-01-01
This paper presents the analysis, design and simulation from a simple DC-UPS converter with integrated back-up and automatic transition. This converter makes automatic transition between the main AC and the battery when a failure occurs, and it delivers uninterrupted DC power to the load through two independent power sources of commercial input power and battery power. The converter has the following characteristics: automatic transition between the main and the battery, no additional control...
星载多路输出开关电源的设计%Design of satellite-borne multi-channel output DC/DC converter
Institute of Scientific and Technical Information of China (English)
张乾; 刘克承; 王卫国
2014-01-01
介绍一款星载多路输出开关电源。该电源的设计方法能够满足绝大部分星载多路输出开关电源的需求。重点介绍该电源的部分设计特点，分析工作原理，并给出了设计公式。实践表明，该电源优化了星载开关电源小型化设计，可广泛应用于星载多路开关电源。%A satellite-borne multi-channel output DC/DC converter is introduced. The method of the power supply design can meet the needs of most of the satellite-borne multi-channel output DC/DC converters. The design characteristics of the power supply are particularly introduced. The operating principle is analyzed. The design formulas are also given. The miniaturization design of the satellite-borne DC/DC converter was optimized. It can be widely used in satellite-borne multi-channel output DC/DC converters.
Modelling and Simulation of Variable Frequency Synchronous DC-DC Buck Converter
Directory of Open Access Journals (Sweden)
Jeya Selvan Renius
2014-10-01
Full Text Available In this paper, novel small-signal averaged models for dc–dc converter operating at variable switching frequency are derived. This is achieved by separately considering the on-time and the off-time of the switching period. The derivation is shown in detail for a synchronous buck converter. The Enhanced Small Signal (ESSA Model is derived for the synchronous buck converter. The equivalent series inductance (ESL is also considered in this modelling. The buck converter model is also simulated in MATLAB and the result is also presented.
Frederick, Martin E. (Inventor); Jermakian, Joel (Inventor)
1991-01-01
A method and an apparatus is provided for efficiently controlling the power output of a solar cell array string or a plurality of solar cell array strings to achieve a maximum amount of output power from the strings under varying conditions of use. Maximum power output from a solar array string is achieved through control of a pulse width modulated DC/DC buck converter which transfers power from a solar array to a load or battery bus. The input voltage from the solar array to the converter is controlled by a pulse width modulation duty cycle, which in turn is controlled by a differential signal controller. By periodically adjusting the control voltage up or down by a small amount and comparing the power on the load or bus with that generated at different voltage values a maximum power output voltage may be obtained. The system is totally modular and additional solar array strings may be added to the system simply by adding converter boards to the system and changing some constants in the controller's control routines.
Chen, Qiang; Ren, Xuemei; Oliver, Jesus Angel
2012-04-01
In this paper, an identifier-based adaptive neural dynamic surface control (IANDSC) is proposed for the uncertain DC-DC buck converter system with input constraint. Based on the analysis of the effect of input constraint in the buck converter, the neural network compensator is employed to ensure the controller output within the permissible range. Subsequently, the constrained adaptive control scheme combined with the neural network compensator is developed for the buck converter with uncertain load current. In this scheme, a newly presented finite-time identifier is utilized to accelerate the parameter tuning process and to heighten the accuracy of parameter estimation. By utilizing the adaptive dynamic surface control (ADSC) technique, the problem of "explosion of complexity" inherently in the traditional adaptive backstepping design can be overcome. The proposed control law can guarantee the uniformly ultimate boundedness of all signals in the closed-loop system via Lyapunov synthesis. Numerical simulations are provided to illustrate the effectiveness of the proposed control method.
Modeling and Design of Five Level Cascaded H-Bridge Multilevel Inverter with DC/DC Boost Converter
Directory of Open Access Journals (Sweden)
Vinayaka B.C
2014-06-01
Full Text Available Power electronic converters, especially DC/AC Sinusoidal Pulse Width Modulation inverters have been extending their range of use in industry because of their numerous advantages. They typically synthesize the stair –case voltage waveform (from several dc sources which has reduced harmonic content. This paper aims to extend the knowledge about the performance of Five level Cascaded H-Bridge MLI topology with DC/DC Boost Converter using SPWM for fixed DC Source. The output voltage is the sum of the voltage that is generated by each bridge. The switching angles can be chosen in such a way that the total harmonic distortion is minimized. This topology incorporates Boost Converter in the input side which magnifies the fundamental output voltage with reduction in total harmonic distortion. It also incorporates LC filter and hence output is drawn near the sine wave because of more levels. Results of experiments proved efficiency of 95%.The performance of the proposed SPWM strategy in terms of output voltage and THD has studied successfully and shown using MATLAB/Simulink.
High efficiency isolated DC/DC converter inherently optimized for fuel cell applications
DEFF Research Database (Denmark)
Petersen, Lars Press; Jensen, Lasse Crone; Larsen, Martin Norgaard
2013-01-01
The isolated full-bridge boost converter has been suggested as the best choice for fuel cell applications. Comparisons have been carried out in the literature using both stress factors and experimental verified designs to determine the optimal converter. Never the less, this paper suggests a diff...
Design and Implementation of Power Flow Control for a novel Dual Input DC-DC Converter
DEFF Research Database (Denmark)
Taeed, Fazel; Ouyang, Ziwei; Nymand, Morten;
2014-01-01
In this paper a control strategy for controlling the power flow from input voltage sources of a novel dual-input dcdc converter to the load is introduced. The converter can be used in renewable energy applications with two independent power sources. Firstly, the operation principle of the converter...... to control the power flow in the converter. The implemented controller in FPGA is low cost and simple. The complete system can be practically used in power management for renewable energy sources....... is outlined; then the control method for adjusting power sharing is proposed. In the next step, the controller is implemented in an FPGA, and then a 350W dual input converter is built to verify operation of the proposed control strategy. The experimental results show the excellent ability of the controller...
Dynamic characteristics of DC-DC converter with novel digital peak current-injected control
Kurokawa, Fujio; Sakemi, Junya; Sukita, Shohei; Shibata, Yuichiro; Soejima, Masato; YOKOYAMA, Tomonori; Sasaki, Masahiro; Mimura, Yasuhiro
2009-01-01
This paper presents the dynamic characteristics of the proposed digital control current mode de-de converter. In the proposed novel digital control circuit, the peak current-injected control is realized using the combination of the simple dual A-Dsignal converter and the programmed delay circuit. In 100kHz digitally controlled de-de converter, it is seen in simulation that the proposed method has no overshoot of the output voltage and the convergencetime that the output voltage is settled to ...
A Two-stage DC-DC Converter for the Fuel Cell-Supercapacitor Hybrid System
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2009-01-01
A wide input range multi-stage converter is proposed with the fuel cells and supercapacitors as a hybrid system. The front-end two-phase boost converter is used to optimize the output power and to reduce the current ripple of fuel cells. The supercapacitor power module is connected by push-pull-forward half bridge (PPFHB) converter with coupled inductors in the second stage to handle the slow transient response of the fuel cells and realize the bidirectional power flow control. Moreover, this...
A Two-stage DC-DC Converter for the Fuel Cell-Supercapacitor Hybrid System
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2009-01-01
A wide input range multi-stage converter is proposed with the fuel cells and supercapacitors as a hybrid system. The front-end two-phase boost converter is used to optimize the output power and to reduce the current ripple of fuel cells. The supercapacitor power module is connected by push-pull......-forward half bridge (PPFHB) converter with coupled inductors in the second stage to handle the slow transient response of the fuel cells and realize the bidirectional power flow control. Moreover, this cascaded structure simplifies the power management. The control strategy for the whole system is analyzed...
Compact DC-DC Converter for Pocket Micro-Controller Systems
Institute of Scientific and Technical Information of China (English)
无
1996-01-01
Novel compact DC-C converters for pocket micro-controller systems are discussed in the paper,which are based on switched capcotprs and inductorless,consequently are more suitable for being hybridized.The new converters enable the pocket microcontroller system to be powered by only one+12V source,while+5V and -12V are converted from the +12V source.The basic principle,voltage ratio,efficiency and ripples are analysed.Experiment and SPICE simulation are also given,which show positive results.
Modeling and control of isolated full bridge boost DC-DC converter implemented in FPGA
DEFF Research Database (Denmark)
Taeed, Fazel; Nymand, M.
2013-01-01
design are discussed. In the next step a digital PI controller is designed and implemented in a FPGA to control the output voltage. Using the injection transformer method the open loop transfer function in closed loop is measured and modeling results are verified by experimental results. © 2013 IEEE.......In this paper an isolated full bridge boost converter (IFBC) firstly is modeled. In the modeling part, a small signal equivalent of the converter is developed. From the small signal model, the converter transfer function is derived. Based on the obtained transfer function, challenges of controller...
Design of discrete time controllers for the DC-DC boost converter
Directory of Open Access Journals (Sweden)
Mohammed Alkrunz
2016-04-01
Full Text Available In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried out.
Design of discrete time controllers for the DC-DC boost converter
Mohammed Alkrunz; Irfan Yazıcı
2016-01-01
In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR) methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried o...
S.Augustilindiya; Palani, S.; K.Vijayarekha; M.BreethiYeltsina
2013-01-01
Tuning PID controller parameters using Evolutionary algorithm for an asynchronous Buck converter is presented in this paper. PID controller is one of the solutions for controlling a Buck converter during transient conditions. There are straight forward ways for calculating the parameters for the PID controller in the literature and evolutionary algorithm based approach with a proper fitnessfunction gives superior performance when compared to other methods. Ziegler Nicholas method, Hurwitz pol...
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)
DC-DC converters in distributed photovoltaic electricity system. Analysis, control and design
Energy Technology Data Exchange (ETDEWEB)
Huusari, J.
2012-10-15
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
A 1 MW, 100 kV, less than 100 kg space based dc-dc power converter
Cooper, J. R.; White, C. W.
1991-01-01
A 1 MW dc-dc power converter has been designed which has an input voltage of 5 kV +/-3 percent, an output voltage of 100 kV +/- 0.25 percent, and a run time of 1000 s at full power. The estimated system mass is 83.8 kg, giving a power density of 11.9 kW/kg. The system exceeded the weight goal of 10 kW/kg through the use of innovative components and system concepts. The system volume is approximately 0.1 cu m, and the overall system efficiency is estimated to be 87 percent. Some of the unique system features include a 50-kHz H-bridge inverter using MOS-controlled thyristors as the switching devices, a resonance transformer to step up the voltage, open-cycle cryogenic hydrogen gas cooling, and a nonrigid, inflatable housing which provides on-demand pressurization of the power converter local environment. This system scales very well to higher output powers. The weight of the 10-MW system with the same input and output voltage requirements and overall system configuration is estimated to be 575.3 kg. This gives a power density of 17.4 kW/kg, significantly higher than the 11.9 kW/kg estimated at 1 MW.
Directory of Open Access Journals (Sweden)
Slamet Kasbi
2015-12-01
Full Text Available Boost DC-DC converters are used in many renewable energy sources including photovoltaic and fuel cell. They are also used in Uninterrupted Power Supply, inverters, electric vehicles and robots. In this paper a boost converter was built and its controller was developed using proportional integral (PI action for current loop and low pass filter (LPF for voltage loop. The controller was derived analytically based on small signal model. Experiment results show that the boost controller functions well in regulating the output voltage under a variation of load. During the start up without any load it can elevate input voltage from 119.6V to output voltage of 241.6V. The developed controller can regulate the output voltage smoothly under load variation from no load to sudden load of 352W. When a large sudden load change happens from 0W to 1042W the output voltage experiences small drop before it is recovered to 241.6V. It can be concluded that the developed control system satisfies the design specification.
Directory of Open Access Journals (Sweden)
Abdul kareem
2011-04-01
Full Text Available Both Soft computing based controllers and sliding mode controllers have been utilized to regulate the output voltage of dc-dc converters in response to changes in the load and the input voltage. Although both control techniques possess desirable characteristics, they have disadvantages which prevent them from being applied extensively. Many researchers have proposed the combination of sliding mode control and Soft computing based control to combine the advantages of both control techniques. In literature survey, it is found that the combination of the methods are proposed so that sliding mode algorithm is used in the design of Soft computing based controllers and the inputs to the controller are error and change in error and the inherent stability property of sliding mode controller is not utilized. This paper presents a novel soft computing based sliding mode controller in which inputs are switching function and change in switching function which combines the advantages of soft computing based controllers, sliding mode controllers and integral controllers. Since soft computing is used in the design of sliding mode controller, the stability of the proposed controller is assured. In addition, it is well suited for digital control design and implementation. The proposed controller has been designed for a buck converter and the controller is able to obtain the desired transient response without causing chattering and error under steady-state conditions. The proposed controller is able to give robust performance in terms of rejection to input voltage variations and load variations.
A study of DC-DC converters with MCT's for arcjet power supplies
Stuart, Thomas A.
1994-01-01
Many arcjet DC power supplies use PWM full bridge converters with large arrays of parallel FET's. This report investigates an alternative supply using a variable frequency series resonant converter with small arrays of parallel MCT's (metal oxide semiconductor controlled thyristors). The reasons for this approach are to: increase reliability by reducing the number of switching devices; and decrease the surface mounting area of the switching arrays. The variable frequency series resonant approach is used because the relatively slow switching speed of the MCT precludes the use of PWM. The 10 kW converter operated satisfactorily with an efficiency of over 91 percent. Test results indicate this efficiency could be increased further by additional optimization of the series resonant inductor.
High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems
DEFF Research Database (Denmark)
Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe;
2016-01-01
This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical ana...
Interleaved Self-Oscillating Class E Derived Resonant DC/DC Converters
DEFF Research Database (Denmark)
Kovacevic, Milovan; Knott, Arnold; Andersen, Michael A. E.
2012-01-01
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...
Observer design for DC/DC power converters with bilinear averaged model
Spinu, V.; Dam, M.C.A.; Lazar, M.
2012-01-01
Increased demand for high bandwidth and high efficiency made full state-feedback control solutions very attractive to power-electronics community. However, full state measurement is economically prohibitive for a large range of applications. Moreover, state measurements in switching power converters
High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems
DEFF Research Database (Denmark)
Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe;
2016-01-01
This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical...
Implementation of Rapid Prototyping Tools for Power Loss and Cost Minimization of DC-DC Converters
Directory of Open Access Journals (Sweden)
Amruta V. Kulkarni
2016-07-01
Full Text Available In this paper, power loss and cost models of power electronic converters based on converter ratings and datasheet information are presented. These models aid in creating rapid prototypes which facilitate the component selection process. Through rapid prototyping, users can estimate power loss and cost which are essential in design decisions. The proposed approach treats main power electronic components of a converter as building blocks that can be arranged to obtain multiple topologies to facilitate rapid prototyping. In order to get system-level power loss and cost models, two processes are implemented. The first process automatically provides minimum power loss or cost estimates and identifies components for specific applications and ratings; the second process estimates power losses and costs of each component of interest as well as the whole system. Two examples are used to illustrate the proposed approaches—boost and buck converters in continuous conduction mode. Achieved cost and loss estimates are over 93% accurate when compared to measured losses and real cost data. This research presents derivations of the proposed models, experimental validation of the models and demonstration of a user friendly interface that integrates all the models. Tools presented in this paper are expected to be very useful for practicing engineers, designers, and researchers, and are flexible and adaptable with changing or new technologies and varying component prices.
Institute of Scientific and Technical Information of China (English)
陈楠; 魏廷存; 陈笑
2016-01-01
针对高频DC-DC开关变换器，提出了数字控制DC-DC开关变换器的邻周期采样（ adjacent cycle sampling ，ACS）控制方法，缓解硬件处理速度与系统瞬态性能之间的矛盾。依据纹波控制方法，ACS控制算法利用硬件空闲阶段采样数据，增大环路预留时间，消除占空比的影响。采用ACS控制算法，推导出适用于后缘调制降压型DC-DC开关变换器的数字V2控制律和电流控制律，并且研究了次谐振荡现象及其数字斜坡补偿消除方法。仿真结果表明，在相同的硬件条件，对于负载的瞬间扰动，数字V2控制较数字电流控制具有更快的瞬态响应速度；与现有技术相比，ACS控制方法可有效提高系统的瞬态响应性能。%Adjacent cycle sampling ( ACS) control method applied to high switching frequency converters for the digitally controlled DC-DC switching converters was proposed .ACS control method can effectively relieve the contradiction between hardware processing speed and transient response performance .Accord-ing to ripple control method,ACS control method sampling the data in idle time increased the available time for duty ratio updating ,and furthermore it was irrelevant to duty ratio .For the buck DC-DC switching converters with trailing-edge modulation ,the control laws of both the digital V 2 control and the digital cur-rent control were derived based on ACS control method .Moreover ,the harmonic oscillation phenomenon of above control laws was analyzed and eliminated using digital slope compensation method .The simula-tion results show that ,for the load instantaneous disturbance ,the digital V 2 control has faster transient re-sponse speed than the digital current control under the same hardware resources .As compared with the conventional technologies ,the ACS control method can effectively improve the transient response perform-ance of DC-DC converters .
Research on control algorithm of DC-DC Boost converters%DC-DC Boost变换器控制算法的研究
Institute of Scientific and Technical Information of China (English)
杨玉岗; 甘汶桦
2015-01-01
为了改善DC⁃DC Boost变换器的性能，在电压控制模式的基础上，设计了PI控制器，对输出电压进行控制。分析了DC⁃DC Boost变换器的基本原理，推导了变换器的传递函数。本文用Zie⁃gler⁃Nichols方法和Loop⁃Shaping方法计算出PI控制器中K p和K i的值，进而通过Matlab仿真和实验，比较了两种方法的输出响应，得出结论：采用Loop⁃Shaping方法能更好改善变换器的性能。%To improve the control performance of DC⁃DC Boost power converters, a PI controller is designed to reg⁃ulate the output voltage based on voltage mode. The basic principle of the DC⁃DC Boost converter have been ana⁃lyzed, and the transfer function of the converter have been derived. The paper uses PI controller in which the val⁃ues of Kp and Ki have been derived using the Ziegler⁃Nichols method and Loop Shaping method, and through Matlab simulation and experiment, the output response of the both methods is compared and conclusion is made that Loop⁃Shaping method can improve the performance of the converter better.
National Aeronautics and Space Administration — The Space Micro ?Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator core...
A High Power Density Three-level Parallel Resonant Converter for Capacitor Charging
Sheng, Honggang
2009-01-01
This dissertation proposes a high-power, high-frequency and high-density three-level parallel resonant converter for capacitor charging. DC-DC pulsed power converters are widely used in military and medical systems, where the power density requirement is often stringent. The primary means for reducing the power converter size has been to reduce loss for reduced cooling systems and to increase the frequency for reduced passive components. Three-level resonant converters, which combine the mer...
Zhioua, M.; El Aroudi, A.; Belghith, S.; Bosque-Moncusí, J. M.; Giral, R.; Al Hosani, K.; Al-Numay, M.
A study of a DC-DC boost converter fed by a photovoltaic (PV) generator and supplying a constant voltage load is presented. The input port of the converter is controlled using fixed frequency pulse width modulation (PWM) based on the loss-free resistor (LFR) concept whose parameter is selected with the aim to force the PV generator to work at its maximum power point. Under this control strategy, it is shown that the system can exhibit complex nonlinear behaviors for certain ranges of parameter values. First, using the nonlinear models of the converter and the PV source, the dynamics of the system are explored in terms of some of its parameters such as the proportional gain of the controller and the output DC bus voltage. To present a comprehensive approach to the overall system behavior under parameter changes, a series of bifurcation diagrams are computed from the circuit-level switched model and from a simplified model both implemented in PSIM© software showing a remarkable agreement. These diagrams show that the first instability that takes place in the system period-1 orbit when a primary parameter is varied is a smooth period-doubling bifurcation and that the nonlinearity of the PV generator is irrelevant for predicting this phenomenon. Different bifurcation scenarios can take place for the resulting period-2 subharmonic regime depending on a secondary bifurcation parameter. The boundary between the desired period-1 orbit and subharmonic oscillation resulting from period-doubling in the parameter space is obtained by calculating the eigenvalues of the monodromy matrix of the simplified model. The results from this model have been validated with time-domain numerical simulation using the circuit-level switched model and also experimentally from a laboratory prototype. This study can help in selecting the parameter values of the circuit in order to delimit the region of period-1 operation of the converter which is of practical interest in PV systems.
Optimal Control with Complete Load-Decoupled Design for the Buck DC-DC Switching Converter
Institute of Scientific and Technical Information of China (English)
Fei-Hu; Hsieh; Yau-Tarng; Juang
2002-01-01
This paper describes a new controller design procedure and turning method for the buck PWM DCDCswitching converter taking into consideration the equivalent series resistance of components. First, the linearoptimal feedback is designed by the LQR approach. Then the designed control law is implemented by aphase-lag lead controller incorporated with a complete load-decoupled PD compensator. The phase-lag lead controlleris tuned to achieve the optimal design based on the output error voltage directly, instead of using an estimator.With the proposed PD compensator, the converter is robust with respect to the load changes and parameterperturbations. We also provide the conditions for the robust stability assurance of the closed-loop system.
Design and implementation of adaptive slope compensation in current mode DC-DC converter
Energy Technology Data Exchange (ETDEWEB)
Guo Zhongjie; Wu Longsheng; Liu Youbao, E-mail: guozhongjie4213@126.com [Xi' an Microelectronic Technology Institute, Xi' an 710054 (China)
2010-12-15
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 {mu}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)
Directory of Open Access Journals (Sweden)
S.Augustilindiya
2013-08-01
Full Text Available Tuning PID controller parameters using Evolutionary algorithm for an asynchronous Buck converter is presented in this paper. PID controller is one of the solutions for controlling a Buck converter during transient conditions. There are straight forward ways for calculating the parameters for the PID controller in the literature and evolutionary algorithm based approach with a proper fitnessfunction gives superior performance when compared to other methods. Ziegler Nicholas method, Hurwitz polynomial method and Genetic Algorithm based method are compared. It is found that Genetic Algorithm based method yields better result. The hardware implementation of Genetic Algorithm assisted PID controller with low cost is desired and such an implementation is taken in this paper. A low cost microcontroller with built-in PWM modules is implemented and the performance is compared with simulations.
Design of high efficiency dual-mode buck DC-DC converter
Xinquan, Lai; Huali, Zeng; Qiang, Ye; Huisen, He; Shasha, Zhang; Yuqing, Sun
2010-11-01
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 μm 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%.
Generalization of zad strategy: an application to a dc-dc buck converter
ANGULO GARCIA, FABIOLA; Olivar Tost, Gerard; Osorio Londoño, Gustavo Adolfo
2011-01-01
The Zero Average Dynamics (ZAD) strategy has been reported in the last decade as an alternative for controlling power converters. This technique has the advantage of guaranteeing fi xed frequency switching. However, the stability of the controller is highly dependent on the load value, and when the stability is lost, the fi xed frequency switching is lost too. In this paper we generalize ZAD strategy using the probabilities framework through the expectation operator. Thus, we recover class...
Directory of Open Access Journals (Sweden)
Xiaolong Shi
2012-12-01
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%.
Generalized computer-aided discrete time domain modeling and analysis of dc-dc converters
Lee, F. C.; Iwens, R. P.; Yu, Y.; Triner, J. E.
1977-01-01
A generalized discrete time domain modeling and analysis technique is presented for all types of switching regulators using any type of duty-cycle controller, and operating in both continuous and discontinuous inductor current. State space techniques are employed to derive an equivalent nonlinear discrete time model that describes the converter exactly. The system is linearized about its equilibrium state to obtain a linear discrete time model for small signal performance evaluations, such as stability, audiosusceptibility and transient response. The analysis makes extensive use of the digital computer as an analytical tool. It is universal, exact and easy to use.
Complete bifurcation analysis of DC-DC converters under current mode control
Pikulin, D.
2014-03-01
The purpose of this research is to investigate to what extend application of novel method of complete bifurcation groups to the analysis of global dynamics of piecewise-smooth hybrid systems enables one to highlight new nonlinear effects before periodic and chaotic regimes. Results include the construction of complete one and two-parameter bifurcation diagrams, detection of various types of bifurcation groups and investigation of their interactions, localization of rare attractors, and the investigation of different principles of birth of chaotic attractors. Effectiveness of the approach is illustrated in respect to one of the most widely used switching systems-boost converter under current mode control operating in continuous current mode.
Soft Switching Full-Bridge PWM DC/DC Converter Using Secondary Snubber
Directory of Open Access Journals (Sweden)
Jaroslav Dudrik
2009-05-01
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.
A Different Three-Port DC/DC Converter for Standalone PV System
Directory of Open Access Journals (Sweden)
Nimrod Vázquez
2014-01-01
Full Text Available A three-port converter suitable for standalone applications is proposed in this paper. Each port is used for specific input or output, and its functions depend on the port; they are the renewable source, the battery set, and the output port. This proposed converter is considered for standalone operation, but it is not limited to it. Not only the system is able to deliver energy independently from each input source or in a mixed way for the output, but also the battery system may be charged from the renewable source just in case it is required. The battery port is only used when it is required; this allows increasing battery lifetime. Another important feature is that, in case of a renewable source failure, the energy is automatically demanded from the battery set, like an uninterruptible power supply. The system is able to track the maximum power of the renewable source when it is required. Operation, analysis, simulation, and experimental results are described in detail.
Implementation of a PV lighting system based on DC-DC converter with intelligent controlled approach
Energy Technology Data Exchange (ETDEWEB)
Hua, C.-C.; Chuang, D.-J. [National Yunlin Univ. of Science and Technology, Douliou, Yunlin, Taiwan (China). Dept. of Electrical Engineering; Chuang, C.-W. [National Yunlin Univ. of Science and Technology, Douliou, Yunlin, Taiwan (China). Graduate School of Engineering Science and Technology
2007-07-01
Photovoltaic (PV) lighting systems for municipalities represent one of the largest cost effective markets for PVs. The installation cost of just one or two utility power poles can justify the initial cost of a PV lighting system. However, many previous PV lighting systems have experienced a number of component failures including premature charge controller, battery, and ballast illumination failures. This paper presented the design and implementation of a digital high performance photovoltaic lighting system based on a microcontroller. A high brightness light-emitting diode (HBLED), was used as it can work at very high efficiency with a specially designed lighting power module. The proposed system consisted of a photovoltaic module, a light emitting diode (LED) lighting module, a bi-directional buck-boost converter and a battery. The paper analysed battery charging methods and proposed a control strategy and hardware implementation. The dimming control methods for LED were also discussed and compared. The experimental results were also provided to verify the theoretical analysis and design procedure of a digital controlled photovoltaic lighting system. It was concluded that the experimental results verified the performance of the proposed photovoltaic lighting system. 8 refs., 1 tab., 18 figs.
Tian, Rui
Magnetic components are essential parts of power converters. Inductors with magnetic cores are investigated. An eddy current loss model for pot-core inductors is developed with finite elemental analysis (FEA). The reliability of inductors using magnetic cores in a high-temperature environment is investigated. Working in up to 150°C circumstance for a short periods is not destructive for the inductors. Optimization of toroidal inductors in a DC-DC converter is investigated. Parasitic capacitance and the capacitive loss in toroidal inductors are modeled. Standard circuit optimization is performed to explore the energy conversion efficiency of the toroidal inductors. Thermal analysis, light-load efficiency and relative permeability of the toroidal inductor design are also investigated. The toroidal inductor can achieve about 85% efficiency for 3 A DC current and 1 W/mm2 power density. Inductor-only efficiency of toroidal inductors is investigated with revised model. At 100 MHz operating frequency, toroidal inductors can achieve more than 97% inductor efficiency with power density range of 0.7 W/mm2 to 6 W/mm2. The performance of our nanograngular magnetic core is dependent on the angle of the poling magnetic field compared to the field during operation. Experiments on a serious of samples show that the poling angle can deviate by up to 15 degrees from ideal with only a small penalty in performance. The field-angle experiment is intended to prove integrated toroidal inductor process possible. A magnetic fixture model is proposed for large-scale toroidal inductor processing.
Energy Technology Data Exchange (ETDEWEB)
Natsheh, Ammar N. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan); Nazzal, Jamal M. [Faculty of Engineering, Al-Ahliyya Amman University, Post Code 19328 Amman (Jordan)]. E-mail: jnazzal@ammanu.edu.jo
2007-08-15
This work describes the bifurcational behavior of a modular peak current-mode controlled DC-DC boost converter with multi bifurcation parameters. The parallel-input/parallel-output converter consists of two identical boost circuits and operates in the continuous-current conduction mode (CCM). A nonlinear mapping in closed form is derived and bifurcation diagrams are generated using MATLAB. A comparison is made between the modular converter diagrams with those of the single boost converter. The effect of introducing mutual coupling between the inductors of the constituent modules is also addressed. Results are verified using the circuit analysis package PSPICE.
Directory of Open Access Journals (Sweden)
Mechouma Rabiaa
2014-01-01
Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.
Arshak, Khalil; Almukhtar, Basil
2000-01-01
peer-reviewed In this work a step by step planar transformer design proccdare for Flybock switch-mode DC-DC converter application is presented. This transformer has a maximum dimention of 2cm x 2cm x 0.4cm aiming to achieve an efficiency of 99% at an operating frequency of 500kHz. This planar transformer is designed specially for thick film technology development.
Béthoux, O.; Cathelin, J.
2010-12-01
Consuming chemical energy, fuel cells produce simultaneously heat, water and useful electrical power [J.M. Andújar, F. Segura, Renew. Sust. Energy Rev. 13, 2309 (2009)], [J. Larminie, A. Dicks, Fuel Cell Systems Explained, 2nd edn. (John Wiley & Sons, 2003)]. As a matter of fact, the voltage generated by a fuel cell strongly depends on both the load power demand and the operating conditions. Besides, as a result of many design aspects, fuel cells are low voltage and high current electric generators. On the contrary, electric loads are commonly designed for small voltage swing and a high V/I ratio in order to minimize Joule losses. Therefore, electric loads supplied by fuel cells are typically fed by means of an intermediate power voltage regulator. The specifications of such a power converter are to be able to step up the input voltage with a high ratio (a ratio of 10 is a classic situation) and also to work with an excellent efficiency (in order to minimize its size, its weight and its losses) [A. Shahin, B. Huang, J.P. Martin, S. Pierfederici, B. Davat, Energy Conv. Manag. 51, 56 (2010)]. This paper deals with the design of this essential ancillary device. It intends to bring out the best structure for fulfilling this function. Several dc-dc converters with large voltage step-up ratios are introduced. A topology based on a coupled inductor or tapped inductor is closely studied. A detailed modelling is performed with the purpose of providing designing rules. This model is validated with both simulation and implementation. The experimental prototype is based on the following specifications: the fuel cell output voltage ranges from a 50 V open-voltage to a 25 V rated voltage while the load requires a constant 250 V voltage. The studied coupled inductor converter is compared with a classic boost converter commonly used in this voltage elevating application. Even though the voltage regulator faces severe FC specifications, the measured efficiency reaches 96% at the
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2014-01-01
the valley switchingtechnique during both charge and discharge processes, withoutthe need to sense signals on the output high-voltage side.Experimental results verifying the bidirectional operation of asingle high voltage flyback converter are presented, using afilm capacitor as the load. Energy......This paper presents a digital control technique toachieve valley switching in a bidirectional flyback converterused to drive a dielectric electro active polymer basedincremental actuator. The incremental actuator consists ofthree electrically isolated, mechanically connected capacitiveactuators....... The incremental actuator requires three highvoltage (~2.5 kV) bidirectional DC-DC converters, toaccomplish the incremental motion by charging anddischarging the capacitive actuators. The bidirectional flybackconverter employs a digital controller to improve efficiencyand charge/discharge speed using...
Energy Technology Data Exchange (ETDEWEB)
Widyan, M.S.
2010-07-01
Photovoltaic (PV) cells for powering direct current (DC) motors are designed to provide maximum output power at the rated conditions of the motors. This paper presented the dynamic and steady-state characteristics of DC shunt, series and permanent-magnet motors fed by PV cells via a DC-DC buck-boost (step up-step down) switch mode converter. It considered the nonlinearities of the output characteristics of the PV cells and that of the magnetization curve of the machines. In order to address the problem of voltage regulation of the PV cells and the variation in solar illumination, the duty cycle controls the output voltage of the DC-DC converter to maintain a fixed voltage across the terminals of the motors at any realistic loading conditions. In this study, the DC-DC buck-boost switch mode converter achieved a fixed voltage across the terminals of the motors and therefore good speed regulation under a wide range of loading conditions and solar intensities. The entire study was carried out using the Matrix Laboratory Program MATLAB{sup TM} software.
DEFF Research Database (Denmark)
Zhang, Zhe; Andersen, Michael A. E.
2013-01-01
This paper presents an isolated dual-input DC-DC converter with a PWM plus phase-shift control for fuel cell hybrid energy systems. The power switches are controlled by phase shifted PWM signals with a variable duty cycle, and thus the two input voltages as well as the output voltage can...... the performance of the proposed PWM converter. The principle of operation is analyzed and some design considerations are discussed. Simulation results using PLECS are given to verify the proposed analysis and design. An experimental converter prototype has been designed, constructed and tested in the laboratory...
Lessa Tofoli, Fernando; Gallo, Carlos Alberto
2011-04-01
This work presents the conception and analysis of a switch-mode power supply with desirable characteristics of high power factor, low harmonic distortion, regulated output voltage, and high efficiency. An interleaved boost converter associated with a nondissipative snubber is used as a preregulator stage. Additionally, a soft switching full-bridge converter is chosen as DC-DC stage. The combination of both topologies results in the proposed switch-mode power supply. Theoretical background on each one of the converters is presented and analytical results are discussed in order to validate the proposal.
电动汽车用数字型直流-直流转换器设计%Design of digital DC-DC converter for electric vehicles
Institute of Scientific and Technical Information of China (English)
滕聪; 黄金强; 禄盛; 黄智宇
2012-01-01
The electric vehicle may win an opportunity due to the pollution of traditional vehicles. The DC-DC converter is an important device for the popularity of electric vehicles, in order to absorb the advantages of digital converter and meet the requirement of wide-range input voltage, the concept of digital DC-DC converters for electric vehicle has been a research subject in EVs area. However, this method requires high dynamic response and wide-range input voltage. A two-stage DC-DC converter controlled by automotive MCU and software was presented, based on the simulation result of small-signal model. The component parameters and test results were described. The results show that the DC-DC converter controlled by digital chip is a real-time programmability, and can meet the requirements of electric vehicles.%随着传统汽车污染的不断增加,以电动汽车为代表的新能源汽车迎来了机遇.而直流-直流( DC-DC)转换器是电动汽车中不可缺少的一种装置.为了吸纳数字型转换器的优点,以及符合宽范围输入电压的要求,电动汽车中用数字型DC-DC转换器已经成为新能源汽车领域中一个热门研究.然而,这种方法需要快速的动态响应.因此,根据其小信号模型仿真结果设计了一个两级转换拓扑的DC-DC转换器,并且设计了基于汽车级数字芯片控制的硬件电路平台和软件算法程序,并给出了DC-DC转换器的元件参数及测试结果.结果表明由数字芯片控制的DC-DC转化器是实时可编程的,也满足汽车电子的要求.
Interleaved high step-up DC/DC converter%一种交错并联高升压DC/DC变换器
Institute of Scientific and Technical Information of China (English)
周雒维; 周远志; 罗全明; 邾玢鑫
2014-01-01
Aiming at the problem that the output voltages of fuel cells are relative low in the typical fuel cell application systems, a non-isolated high step-up DC/DC converter was proposed , which is based on traditional Boost three-terminal network connecting in series with DCM ( diode-capacitor multiplier, DCM) boost units composed of diodes and capacitors to improve its input and output gain. Theoretical a-nalysis and experimental results show that the presented converter meets the requirement for high step-up and has the following advantages. The switches and diodes were operated under low voltage stress. It is feasible to choose the switches with lower conduction resistance to enhance the efficiency. All the diodes have equal current and voltage stress is good for heat sinks design. It is flexible to change the number of DCM units to meet the various requirement for high step-up of different applications. The interleaved in-put form of this converter is more suitable for heavy input current applications. And this converter a-chieves automatic current-sharing with two-phase input and easy control.%针对燃料电池应用系统中电池输出电压低的问题,提出一种具备高增益升压能力的非隔离型DC/DC变换器,该变换器通过在传统Boost三端口网络中串入由二极管和电容构建的DCM ( di-ode-capacitor multiplier, DCM)升压单元来提高其输入输出增益。理论分析和实验结果表明,该变换器在提高输入输出增益的同时还具备以下优点：(1)开关器件电压应力低,可以选择更低导通电阻的开关管提高变换器工作效率；(2)所有二极管的电流电压应力均相等,有利于散热器设计；(3)输入输出增益可以通过DCM单元数来调节,方便根据输入输出工况做出合适的调整；(4)交错并联的输入形式,更适合于大电流输入的应用场合；(5)两相输入电流可以实现自动均流,控制方便。
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2012-01-01
The Dielectric Electro Active Polymer (DEAP) material is a very thin (~80 μm) 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....... 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...
采用LCD箝位电路的正激DC-DC变换器%A Forward DC-DC Converter with a LCD Clamp Circuit
Institute of Scientific and Technical Information of China (English)
王国礼; 金新民
2000-01-01
In this paper a forward DC-DC converter with a LCD clamp circuit is propsed. The core is reset through this simple clamp circuit, and the efficiency of the converter is improved due to avoiding the energy loss.%介绍了一种采用LCD箝位电路的正激DC-DC变换器，它以十分简单的电路结构实现了变压器铁心的磁通复位，并且避免了能量的损耗，提高了变换器的效率。
Dhawan, S; Tipton, P; Kierstead, J; Lynn, D; rescia, S; Weber, M
2007-01-01
For more efficient power transport to the electronics embedded inside large colliding beam detectors, we explore the feasibility of supplying higher DC voltage and using local DC-DC conversion to 1.3 V (or lower, depending upon on the lithography of the embedded electronics) using switch mode regulators located very close to the front end electronics. These devices will be exposed to high radiation and high magnetic fields, 10 – 100 Mrads and 2 - 4 Tesla at the SLHC.
A three-phase current-fed dc/dc converter with a three-leg high frequency transformer for fuel cells
Energy Technology Data Exchange (ETDEWEB)
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
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)
升压型 DC-DC转换器的设计与研究%The Study and Design of the Boost DC-DC Converter
Institute of Scientific and Technical Information of China (English)
2013-01-01
主要研究了一种高转换效率、低输出纹波的升压型DC-DC转换器．该转换器具有很高的转换效率、低工作电压、欠电流与过电流检测和节电模式控制等特性．通过带隙基准电压源对转换器内部工作点提供偏置，大大地提高了系统的稳定性，提高了抗电源电压波动，温度的变化以及噪声引起的干扰的抑制．采用0．25μmCMOS工艺，其转换效率可达到90％以上．在输入电压为2．5V的条件下，输出电压为标准的3．3V和5V ．%A high efficiency , low output ripple boost DC-DC converter was studied and designed . The DC-DC converter achieves high dc to dc converting efficiency ,low power supply ,low current and over current detection , saving mode control .The bias voltage of nodes inside of DC-DC converter are set by the bandgap reference voltage circuit ,therefore , the system stability , suppressed power supply noise and effect of temperature variation is enhanced .The circuit simulation is based on the 0 .25μm process ,its conversion rate is grater than 90% .When input voltage is 2 .5V ,the output voltage are standard 3 .3V and 5V .
DEFF Research Database (Denmark)
Gohil, Ghanshyamsinh Vijaysinh; Wang, Huai; Liserre, Marco;
2014-01-01
A method to selectively control the amount of dc link voltage ripple by processing desired reactive power by a DC/DC converter in isolated AC/DC or AC/DC/AC system is proposed. The concept can reduce the dc link capacitors used for balancing the input and output power and thereby limiting the vol...
A High Gain Interleaved Coupled-inductor DC/DC Converter%一种高增益交错耦合电感直流变换器
Institute of Scientific and Technical Information of China (English)
胡雪峰; 龚春英; 陈杰; 王琳
2014-01-01
A novel high step-up interleaved dc-dc converter topology with two coupled-inductors is presented for low input voltage and high input current applications, such as photovoltaic and fuel cell generation systems. In the proposed converter, the primary currents of two coupled-inductors are interleaved in parallel at input, which reduces the input current ripple. The secondary sides of two coupled-inductors are connected in series with a capacitor for a double voltage cell to improve the voltage gain further. Moreover, this structure can also reduce the voltage/current stresses of active switches and diodes. The leakage energy can also be recycled by the two output capacitors, which are charged interleaving in parallel and discharged in series. In addition, the reverse-recovery problems of diodes are alleviated significantly by the leakage inductance. The operating principle and the steady-state characteristics are discussed in detail to show the merits of the presented converter and the corresponding model is also derived. Finally, a rating prototype system is constructed to verify the effectiveness of the proposed converter.%提出一种高增益交错耦合电感直流-直流升压变换器，适用于低输入电压、高输入电流的低压可再生能源发电系统应用场合，如光伏/燃料电池发电系统。该变换器在输入端把两个耦合电感的原边电流进行交错并联，减小了输入电流和输出电压纹波；两个耦合电感的副边串联后再与一电容相结合组成倍压单元，进一步提高变换器的电压增益。该电路结构中，使用两个交错串联的输出电容，它们既能回收利用耦合电感的漏感能量，又能钳位开关管的漏源电压，减小开关管电压应力，因此，有利于选择低导通电阻、高性能的开关器件以进一步减小功率管的开关和导通损耗。另外，耦合电感的漏感可使主开关管零电流开通，同时漏感也能控制二极管
Fuentes Rojas, Cristian Alejandro; Blanchot, G
2011-01-01
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.
Institute of Scientific and Technical Information of China (English)
Zhang Chunhong; Yang Haigang; Richard Shi
2013-01-01
A synchronous buck DC-DC converter with an adaptive multi-mode controller is proposed.In order to achieve high efficiency over its entire load range,pulse-width modulation (PWM),pulse-skip modulation (PSM)and pulse-frequency modulation (PFM) modes were integrated in the proposed DC-DC converter.With a highly accurate current sensor and a dynamic mode controller on chip,the converter can dynamically change among PWM,PSM and PFM control according to the load requirements.In addition,to avoid power device damage caused by inrush current at the start up state,a soft-start circuit is presented to suppress the inrush current.Furthermore,an adaptive slope compensation (SC) technique is proposed to stabilize the current programmed PWM controller for duty cycle passes over 50％,and improve the degraded load capability due to traditional slope compensation.The buck converter chip was simulated and manufactured under a 0.35μm standard CMOS process.Experimental results show that the chip can achieve 79％ to 91％ efficiency over the load range of 0.1 to 1000 mA.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;
2009-01-01
Abstract-In this paper, an extended run time DC UPS system structure with fuel cell and supercapacitor is investigated. A wide input range bi-directional dc-dc converter is described along with the phase-shift modulation scheme and phase-shift with duty cycle control, in different modes...... input voltage combined with load current feedback using PI controller with anti-windup scheme to realize closed-loop control of the whole system, and verify the feasibility of the control scheme proposed by simulation. A 1kW prototype controlled by TMS320F2808 DSP is implemented and tested. Experimental...
Sai, Toru; Sugimoto, Yasuhiro
By using a quadratic compensation slope, a CMOS current-mode buck DC-DC converter with constant frequency characteristics over wide input and output voltage ranges has been developed. The use of a quadratic slope instead of a conventional linear slope makes both the damping factor in the transfer function and the frequency bandwidth of the current feedback loop independent of the converter's output voltage settings. When the coefficient of the quadratic slope is chosen to be dependent on the input voltage settings, the damping factor in the transfer function and the frequency bandwidth of the current feedback loop both become independent of the input voltage settings. Thus, both the input and output voltage dependences in the current feedback loop are eliminated, the frequency characteristics become constant, and the frequency bandwidth is maximized. To verify the effectiveness of a quadratic compensation slope with a coefficient that is dependent on the input voltage in a buck DC-DC converter, we fabricated a test chip using a 0.18µm high-voltage CMOS process. The evaluation results show that the frequency characteristics of both the total feedback loop and the current feedback loop are constant even when the input and output voltages are changed from 2.5V to 7V and from 0.5V to 5.6V, respectively, using a 3MHz clock.
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2013-01-01
-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...
Energy Technology Data Exchange (ETDEWEB)
Averberg, Andreas
2009-07-01
Fuel cells in the kW range have relatively high output currents and low output voltages, which strongly depend on the load. Furthermore, ripple currents have a negative impact on efficiency and lifetime of the cells. These characteristics have to be taken into consideration in the design process of a dc-dc converter for fuel cell applications. This work focuses on the investigation of voltage-fed, current-fed and two-stage converters, comparing them with respect to their suitability for the use in fuel cell systems. For this purpose, analytical calculations are given, completely describing the operating behaviour of each individual topology. As a consequence, it is possible to present the trend of characteristic values as e.g. rms currents in all devices and the magnetic stress in the inductive components, depending on topology and operating parameters. The impact of switching frequency, the transformer's leakage inductance and its winding ratio and the value of an optional input or output inductor is clearly and completely stated out. Furthermore, depending on the aforementioned papameters, the location of optimum efficiency can be specified for all operating conditions. The power losses can be divided into their single parts. In this way, an optimised converter design is provided. Due to the leakage inductance in combination with a high switching frequency, the transferable power is limited in the investigated one-stage converters. This can especially be noticed in low input voltage applications, as is the case in fuel cell systems. An analytical equation for the maximum power of each dc-dc converter is deduced. Base on the analytical investigations, a comparison of the different dc-dc converters is done. Assuming equal chip areas of the semiconductor devices, equal ripple currents at the input of each topology and with consideration of the overall installed size, the converter efficiencies are calculated for full load as well as for partial load. This
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 μm 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 μs 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)
Institute of Scientific and Technical Information of China (English)
Ye Qiang; Liu Jie; Yuan Bing; Lai Xinquan; Liu Ning
2012-01-01
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 μm 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 μs 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％.
Directory of Open Access Journals (Sweden)
R. Silva-Ortigoza
2014-01-01
Full Text Available Sliding mode control is a discontinuous control technique that is, by its nature, appropriate for controlling variable structure systems, such as the switch regulated systems employed in power electronics. However, when designing control laws based on the average models of these systems a modulator is necessary for their experimental implementation. Among the most widely used modulators in power electronics are the pulse width modulation (PWM and, more recently, the sigma-delta-modulator (Σ-Δ-modulator. Based on the importance of achieving an appropriate implementation of average control laws and the relevance of the trajectory tracking task in DC/DC power converters, for the first time, this research presents the assessment of the experimental results obtained when one of these controllers is implemented through either a PWM or a Σ-Δ-modulator to perform such a task. A comparative assessment based on the integral square error (ISE index shows that, at frequencies with similar efficiency, the Σ-Δ-modulator provides a better tracking performance for the DC/DC Buck converter. In this paper, an average control based on differential flatness was used to perform the experiments. It is worth mentioning that a different trajectory tracking controller could have been selected for this research.
Anlin, He; Gang, Guo; Shuting, Shi; Dongjun, Shen; Jiancheng, Liu; Li, Cai; Hui, Fan
2015-11-01
This paper tested and analyzed heavy ion and proton induced single event effects (SEE) of a commercial DC/DC converter based on a 600 nm Bi-CMOS technology. Heavy ion induced single event transients (SET) testing has been carried out by using the Beijing HI-13 tandem accelerator at China Institute of Atomic Energy. Proton test has been carried out by using the Canadian TRIUMF proton accelerator. Both SET cross section versus linear energy transfer (LET) and proton energy has been measured. The main study conclusions are: (1) the DC/DC is both sensitive to heavy ion and proton radiations although at a pretty large feature size (600 nm), and threshold LET is about 0.06 MeV·mg/cm2 (2) heavy ion SET saturation cross section is about 5 magnitudes order larger than proton SET saturation cross section, which is consistent with the theory calculation result deduced by the RPP model and the proton nuclear reaction model; (3) on-orbit soft error rate (SER) prediction showed, on GEO orbit, proton induced SERs calculated by the heavy ion derived model are 4-5 times larger than those calculated by proton test data.
Cosp Vilella, Jordi; Martínez García, Herminio
2015-01-01
Hybrid DC-DC regulators are structures that combine both a linear voltage regulator and a switching DC-DC converter. The main objective of this hybrid topology is to converge, in a single circuit topology, the best of both alternatives: a small voltage output ripple, which is a common characteristic of linear regulator circuits, and good energy efficiency, as in switching alternatives. While the linear regulator fixes the required output voltage to a fixed value with negligible steady-state r...
Directory of Open Access Journals (Sweden)
Kosenko Roman
2015-07-01
Full Text Available This paper compares semiconductor losses of the galvanically isolated quasi-Z-source converter and full-bridge boost DC-DC converter with active clamping circuit. Operation principle of both converters is described. Short design guidelines are provided as well. Results of steady state analysis are used to calculate semiconductor power losses for both converters. Analytical expressions are derived for all types of semiconductor power losses present in these converters. The theoretical results were verified by means of numerical simulation performed in the PSIM simulation software. Its add-on module “Thermal module” was used to estimate semiconductor power losses using the datasheet parameters of the selected semiconductor devices. Results of calculations and simulation study were obtained for four operating points with different input voltage and constant input current to compare performance of the converters in renewable applications, like photovoltaic, where input voltage and power can vary significantly. Power loss breakdown is detailed and its dependence on the converter output power is analyzed. Recommendations are given for the use of the converter topologies in applications with low input voltage and relatively high input current.
Wide input high step-up isolated DC/DC converter%宽输入高增益隔离升压型DC/DC变换器
Institute of Scientific and Technical Information of China (English)
肖文英; 戴日光
2012-01-01
隔离升压型DC/DC变换器是一类可以将低压直流母线变换成高压直流母线并实现电气隔离的变换器的统称.该技术在新能源发电领域如燃料电池发电系统以及微逆变器系统中应用广泛,其研究热点是宽输入适应性、高增益和高效率功率变换.LLC谐振变换器很好地符合这些要求.为此,研究了基于全桥LLC谐振变换器的高增益隔离升压型DC/DC变换器,提出了单级式和两级式两种方案,单级式方案为输出稳压LLC谐振变换器,而两级式方案为Boost变换器级联输出不稳压LLC谐振变换器.分别提出了LLC谐振变换器在单级式和两级式方案中的基于最佳励磁电感的谐振腔参数设计方法,并且分别通过样机实验验证了所提出的设计方法的有效性.%The isolated step-up DC/DC converter is a kind of converter that can convert low DC voltage bus into high DC voltage bus and realize electrical isolation. This technology has been widely used in new energy generation, such as fuel cell power system and micro-inverter system. Its research focuses on wide input adaptation, high step-up and high efficiency power conversion. LLC resonant converter perfectly satisfies these requirements. For this reason, high step-up DC/DC converter based on full bridge LLC resonant converter was studied in this paper. Two structures were presented, namely, single-stage structure applying regulated LLC resonant converter and two-stage structure applying Boost converter cascaded unregulated LLC resonant converter. The design method of the resonant tank under different structures based on the optimal magnetizing inductance was proposed. Finally, the prototypes of regulated and unregulated LLC resonant converter were built to verify the verification of the proposed method.
Design of Novel DC/DC Converter for Photovoltaic Power Generation System%光伏发电系统的新型DC/DC变换器设计
Institute of Scientific and Technical Information of China (English)
陈晓; 孙以泽; 徐洋; 孟婥
2011-01-01
Aiming at the problems of hard-switching loss and one-way saturation of transformer magnetic cores caused by inconsistency switching characteristic in traditional full-bridge DC/DC converter, a novel phase-shift ZVS full-bridge DC/DC converter used in photovoltaic power system is designed in this paper. The control circuit adopts double-loop feedback program with chip UC3875 and the driving circuit is composed of the dedicated driving integrated chip IR2110S. This converter can achieve soft-switching, reduce the switching losses and improve the system efficiency. Moreover, it eliminates the magnetic bias, and the work of the transformer flux density can approach the saturation point. Finally, a prototype is built for verifying the design reliability.%针对传统全桥DC/DC变换器存在的硬开关损耗和因开关管开关特性不一致使变压器原边磁芯单向饱和问题,设计了一种用于光伏发电系统中的移相ZVS全桥DC/DC变换器,控制电路采用基于芯片UC3875的双环反馈方案,驱动电路由专用驱动集成芯片IR2110S构成.不仅实现了开关管的软开关控制、降低开关损耗、提高系统效率,还可解决偏磁问题,使变压器的磁通密度工作接近于饱和点.实验样机的研制验证了设计的可靠性.
Iyappan, K; Basha, C Ahmed; Saravanathamizhan, R; Vedaraman, N; Tahiyah Nou Shene, C A; Begum, S Nathira
2014-01-01
Electrochemical oxidation of tannery effluent was carried out in batch, batch recirculation and continuous reactor configurations under different conditions using a battery-integrated DC-DC converter and solar PV power supply. The effect of current density, electrolysis time and fluid flow rate on chemical oxygen demand (COD) removal and energy consumption has been evaluated. The results of batch reactor show that a COD reduction of 80.85% to 96.67% could be obtained. The results showed that after 7 h of operation at a current density of 2.5 A dm(-2) and flow rate of 100 L h(-1) in batch recirculation reactor, the removal of COD is 82.14% and the specific energy consumption was found to be 5.871 kWh (kg COD)(-1) for tannery effluent. In addition, the performance of single pass flow reactors (single and multiple reactors) system of various configurations are analyzed.
Directory of Open Access Journals (Sweden)
E. Durán
2012-01-01
Full Text Available A versatile measurement system for systematic testing and measurement of the evolution of the I-V characteristic curves of photovoltaic panels or arrays (PV generators is proposed in this paper. The measurement system uses a circuit solution based on DC-DC converters that involves several advantages relative to traditional methods: simple structure, scalability, fast response, and low cost. The measurement of the desired characteristics of PV generators includes high speed of response and high fidelity. The prototype system built is governed by a microcontroller, and experimental results prove the proposed measurement system useful. A virtual instrument (VI was developed for full system control from a computer. The developed system enables monitoring the suitable operation of a PV generator in real time, since it allows comparing its actual curves with those provided by the manufacturer.
Design of a Dual-phase DC-DC Converter With High Gain%具有高增益的双相直流变换器设计
Institute of Scientific and Technical Information of China (English)
胡雪峰; 龚春英
2012-01-01
为了获得较高的电压增益,减小开关管的电压、电流应力,将2个中间储能电容与传统双相BOOST升压电路相结合,研究了一种具有高电压增益的新型双相BOOST电路拓扑。该电路具有以下明显的特点：在相同占空比的情况下能有效提高变换器升压增益,可实现更大的功率变换;主开关管和所增加二极管的电压应力只有输出电压的一半,因此对相同功率级的升压电路,不仅可以选择低耐压、高性能的开关器件,而且可以降低电路的损耗。详细分析了新型双相BOOST变换器的工作原理,制作了1台额定功率为1kW原理样机,通过实验验证了理论分析的正确性和可行性。结果表明,所提出的新型双相BOOST变换器性能优良,结构简单,具有实用价值。%In order to obtain high step-up static gain,reduce maximum voltage and current stress of switches,a novel dual-phase DC-DC BOOST converter was proposed by combining two diodes and two storage capacitors with traditional dual-phase BOOST converter.Compared with traditional BOOST converter,the proposed converter has lots of advantages： the converter increases the voltage gain at the same duty and improves the power efficiency,the voltage stress of the switches and added diode-capacitor set are only half of the output voltage,so it is very useful to select switches with low voltage and high performance to reduce loss of the circuit for the same power converters.The operation principle of proposed converter was analyzed in the paper,and a prototype of BOOST converter rated at 1 kW had been built to confirm the effectiveness of the converter.The experimental results proved that the proposed dual-phase BOOST converter has a simple and feasible structure with good performance.
Soft-Switching Resonant Reset Dual Switch Forward DC/DC Converter%软开关谐振复位双管正激DC/DC变流器
Institute of Scientific and Technical Information of China (English)
洪小圆; 陈威; 吕征宇
2009-01-01
提出了一种新颖的双管正激DC/DC变流器,利用谐振复位使变流器工作在0.5以上的占空比,利用变压器二次侧串联饱和电感的方法使变流器所有开关管实现软开关,适于宽范围输入、高效率要求的应用场合.分析了变流器的工作原理,对变流器的特性进行了详细的分析.最后以一台250～400V直流输入,54V/5A输出的样机验证了该变流器的可行性.%This paper presents a new dual switch forward DC/DC converter topology. The duty cycle can be more than 0.5 by resonant reset. In addition, soft switching operation is achieved for all switches of the presented converter by adding a saturable reactor . It means that the converter is very attractive for wide range input and high efficiency application. In this paper, the operation principle and characteristic of this converter are analysed in details. Finally, the advantages mentioned above are verified by a 250~400V input, 54V/5A output prototype.
不对称控制全桥副边双谐振DC-DC变换器%Asymmetrical Full-bridge Secondary Dual Resonance DC-DC Converters
Institute of Scientific and Technical Information of China (English)
陈章勇; 肖皓中; 陈利; 许建平
2013-01-01
An asymmetrical full-bridge secondary dual resonance (FB-SDR) DC-DC converter is proposed. Without auxiliary circuits, the proposed converter can achieve zero voltage switching (ZVS) for the power switches and zero current switching (ZCS) for the rectifier diodes in the entire operating range. The switching losses and diode reverse-recovery losses are thus decreased. The circulating current loss is eliminated with the asymmetrical PWM strategy. Moreover, the proposed converter eliminates the voltage spike and oscillation of the rectifier diodes, clamps the diode voltage at the output voltage to decrease the voltage stress of the rectifier diodes. The analysis and design considerations of the converter are presented. Finally, experimental results from a 1 kW 400 V/48 V prototype were presented to verify the analysis of the proposed converter.%提出一种全桥副边双谐振(full-bridge secondary-dual-resonance，FB-SDR)DC-DC 变换器。变换器无需添加辅助电路即可在全负载范围内实现开关管的零电压开关和副边整流二极管的零电流关断，减小了开通损耗和反向恢复损耗；同时，采用不对称控制策略，消除了传统移相全桥变换器的环流损耗，提高了变换器的效率；有效抑制了整流二极管的电压尖峰和振荡，将整流二极管电压箝位在输出电压，减小了电压应力，进一步提高了变换器的性能。详细研究FB-SDR变换器的工作原理及稳态特性，并对电路关键参数进行设计。最后，通过搭建一台1 kW、400 V/48 V 的实验样机，验证理论分析的正确性。
Integrated Diagnostic/Prognostic Experimental Setup for Capacitor Degradation and Health Monitoring
National Aeronautics and Space Administration — This paper proposes the experiments and setups for studying diagnosis and prognosis of electrolytic capacitors in DC-DC power converters. Electrolytic capacitors...
适合于混合动力汽车新型双向DC/DC变换器研究%Study of One Bi-directional DC/DC Converter for Hybrid Electric Vehicle
Institute of Scientific and Technical Information of China (English)
胡建明
2011-01-01
首先介绍了一种混合动力汽车的基本电路,然后根据要求设计了一种双向变换器,它具有高功率传输能力和最小开关应力,适合于连接超级电容器来驱动混合动力汽车.与一些典型的隔离式双向DC/DC变换器相比,该变换器具有较低的设备应力,并且可通过相移加PWM控制,采用隔离变压器的漏感作为能量传输单元和控制变量.最后,实验波形证明该变换器能较好地应用于混合动力汽车.%The paper first introduces the basic drive system of a hybrid electric vehicle.Then the selection and design of aforementioned converter are proposed. The converter has high powerflow capability and minimum device stresses that can suitably interface a super capacitor with the drive train of a hybrid electric vehicle. Furthermore ,by comparing of the main characteristics and applications with some typical isolated bi-directional DC/DC converter, the proposed converter has low device rating and can be controlled by duty cycle and phase shift. At last,the most important characteristics of this converter is to uses the transformer leakage inductance as the primary energy transfer element and control parameters, the experimental waveforms are given to demonstrate the goodness of this novel topology which is in particular for hybrid electric vehicle.
Directory of Open Access Journals (Sweden)
T.NageswaraRao
2012-07-01
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.
Energy Technology Data Exchange (ETDEWEB)
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
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)
Comparative Study on Paralleled vs. Scaled Dc-dc Converters in High Voltage Gain Applications
DEFF Research Database (Denmark)
Klimczak, Pawel; Munk-Nielsen, Stig
2008-01-01
'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...
Family of Step-up DC/DC Converters with Fast Dynamic Response for Low Power Applications
DEFF Research Database (Denmark)
N. Soltani, Mohsen; Mostaan, Ali; Siwakoti, Yam Prasad;
2016-01-01
is presence of only two switches in the basic converter and its derivatives. The dynamic performance of the proposed converter and its first derivative is analysed by small-signal model using the state-space averaging method. The theoretical model is verified by experiments using GaN high-electron...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2014-01-01
and medical industries. The design of the bidirectional flyback converter to charge and discharge a 400 nF capacitive actuator is presented, when 4 kV and 4.5 kV high voltage MOSFETs are used on the secondary high voltage side. The experimental results and efficiency measurements of the converter...
Thermal Modeling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Zygimantas; Zhang, Zhe; Pittini, Riccardo;
2014-01-01
Power electronic converters are widely used and play a pivotal role in electronics area . The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determine...
Thermal Modelling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Z.; Zhang, Z.; Pittini, R.;
2014-01-01
Power electronic converters are widely used and play a pivotal role in electronics area. The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determined...
Dual-Input Isolated Full-Bridge Boost DC-DC Converter Based on the Distributed Transformers
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;
2012-01-01
, 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...
Design of DC-DC Converter and its Control for a Wind Generation System Connected to an Isolated Load
Directory of Open Access Journals (Sweden)
Carlos A. Ramírez Gómez
2013-11-01
Full Text Available A method to design a Buck converter and its control, which are associated to a wind generation system that is feeding an isolated load, is presented in this paper. To design the converter a Thevenin equivalent is deduced, which represents the behavior of the wind turbine, the permanent magnet synchronous generator, and the rectifier. The design of the converter elements guarantees input/output voltages and inductor current ripples of 5 % or less. The output voltage control is developed with a proportional-integral-derivative controller and as design criteria a damping of 0,707 and cutoff frequency of 1/5 converter commutation frequency are selected. The designed controller regulates the output voltage faced load perturbations and wind speed variations.
An integrated DC-DC step-up charge pump and step-down converter in 130 nm technology
Bochenek, M; Faccio, F; Kaplon, J
2009-01-01
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.
Górecki, Krzysztof; Zarębski, Janusz
In the paper the influence of the ferromagnetic material used for the construction of the core of the impulse-transformer on the characteristics of a half-bridge converter is considered. The investigated network is described and some results of measurements are shown. On the basis of the obtained characteristics of the investigated converters some suggestions for the designers of such circuits are formulated.
Self-Starting DC:DC Boost Converter for Low-Power and Low-Voltage Microbial Electric Generators
Degrenne, Nicolas; Buret, François; Morel, Florent; Adami, Salah-Eddine; Labrousse, Denis; Allard, Bruno; Zaoui, Abderrahime
2011-01-01
International audience This paper describes and evaluates an original boost converter able to harvest energy from low-power and lowvoltage power sources. Design and sizing are made according to specifications issued from the stringent characteristics of microbial electric generators such as microbial fuel cells and microbial desalination cells. The harvested power is 10mW under input voltage Vin=0.3V (33mA input current). The design of the converter is adapted from a classical boost topolo...
A Low-Cost Soft-Switched DC/DC Converter for Solid-Oxide Fuel Cells
Energy Technology Data Exchange (ETDEWEB)
Jason Lai
2009-03-03
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.
A bi-directional DC/DC converter for hybrid wind generator/battery system with state machine control
Energy Technology Data Exchange (ETDEWEB)
Hua, C.C.; Liao, Y.C. [National Yunlin Univ. of Science and Technology, Yunlin, Taiwan (China). Dept. of Electrical Engineering
2008-07-01
A bi-directional DC to DC converter used in a hybrid wind generator/lead-acid battery power system was presented. A state machine control strategy was used to control both the system power flow and load distribution. It was also used to increase the power capacity of the system. The battery was also charged or discharged through the bi-directional DC to DC converter. Multi-stage current charging control of the batteries was accomplished by adjusting the duty cycle of the power converter. This also improved the charging efficiency by the maximum power point tracking algorithm. It was concluded that the proposed control method can be readily extended to other renewable energy conversion systems. 6 refs., 13 figs.
Energy Technology Data Exchange (ETDEWEB)
Kalantar, M.; Mousavi G., S.M. [Center of Excellence for Power System Automation and Operation, Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran (Iran)
2010-10-15
In this paper, modeling, analysis, design, simulation and control of a single ended primary inductor converter (SEPIC) are discussed for renewable energy applications. Because the traditional control methods such as proportional-integral-derivative (PID) and classical half-cycle Posicast controllers based on feedforward are sensitive to noise and variations in natural frequency, a Posicast control with feedback structure is proposed and designed to reduce or rejection undesirable sensitivity greatly, to suppress measurement noise and to eliminate the overshoot in the output response. The SEPIC converter is modeled using average value modeling analysis. Dynamic modeling and simulation are accomplished using MATLAB Simulink trademark 7.2. (author)
Kang, Yonghan
2005-01-01
Pulse power system is widely used for medical, industrial and military applications. The operational principle of the pulse power system is that the energy from the input source is stored in the capacitor bank or superconducting inductive device through a dc-dc converter. Then, when a discharging signal exists, the stored energy is released to the load through pulse forming network (PFN) generating high peak power pulse up to gigawatts within several tens of or hundreds of microseconds. ...
On the Development of High Power DC-DC Step-Down Converter with Energy Recovery Snubber
Directory of Open Access Journals (Sweden)
Alok Singh
2012-01-01
Full Text Available The effect of switching losses on the efficiency of a switch mode power converter and methods adopted for its improvement using an energy recovery lossless snubber has been presented. A comparative analysis of various types of soft switching techniques along with effects of dissipative and nondissipative snubbers on efficiency of the converter has been carried out before zeroing in on the selected scheme. The selected snubber serves the dual function of a turn-on and turn-off snubber and thereby reducing the switching losses both during turn-on and turn-off transients, resulting in improved efficiency of the converter. A detailed design procedure of the snubber for high-power applications taking into account various effects such as diode reverse recovery, diode voltage stress, and minimum and maximum duty cycle limits, has been presented in this paper. Importance of practical aspects in layout to minimize wiring inductance is also highlighted. A high-power prototype of buck converter has been developed to experimentally validate the theoretical design and analytical observations.
Single-Event Transient Testing of the Crane Aerospace and Electronics SMHF2812D Dual DC-DC Converter
Casey, Megan
2015-01-01
The purpose of this testing was to characterize the Crane Aerospace & Electronics (Crane) Interpoint SMHF2812D for single-event transient (SET) susceptibility. These data shall be used for flight lot evaluation, as well as qualification by similarity of the SMHF family of converters, all of which use the same active components.
Thermal Modelling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Z.; Zhang, Z.; Pittini, R.;
2014-01-01
the potential of such analysis was demonstrated by real-world measurements and comparison of obtained results. Thermal modelling was accomplished using finite element analysis software COMSOL and thermo-imaging camera was used to measure the thermal field distribution. Also, the improved configuration of power......Power electronic converters are widely used and play a pivotal role in electronics area. The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determined...... by numerical modelling techniques. Therefore, thermal design through thermal modelling and simulation is becoming an integral part of the design process as less expensive compared to the experimental cut-and-try approach. Here the investigation is performed using finite element method-based modelling, and also...
Simpliﬁed loss analysis and comparison of full-bridge, full-range-ZVS DC-DC converters
Indian Academy of Sciences (India)
Shubhendu Bhardwaj; Mangesh Borage; Sunil Tiwari
2008-10-01
The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters. Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS DC–DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to be consistent with the experimental efﬁciency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently proposed new topology has the least penalty of additional losses.
Multi-Purpose Low Voltage Dual Output DC-DC Converter For 100V Power Bus Telecom Platform
Galiana, D.; Mollard, J. M.
2011-10-01
The decreasing supply voltages of digital electronic and high speed ADC (Analog to Digital Converter) and DAC (Digital to Analog Converter) require flexible and high current secondary power distribution system. In the frame of the Inmarsat I-XL program, a 12 kW geomobile SatCom satellite, with 100 V regulated power bus, a multi purpose dual output converter was developed for the payload processor as a building block. After a short introduction on the main performance requirements, the baseline architecture is presented. The main drivers of the architecture are reliability, adjustability, radiation tolerant and single event free, volume and mass. The combination of all these constraints highlights the need of significant breakthrough in various domains. Many research results related to packaging and power electronic topics are brought up. These results directly drive the adopted solution presented in the next step followed by a description of the integration of the defined building block in the Inmarsat I-XL payload IP (Integrated Processor). Finally, the main electrical performances such as output ripple and spikes, load step transient and stability are summarized.
移相全桥DC/DC变换器智能控制方法研究%Research on the intelligent control of PSFB DC/DC converter
Institute of Scientific and Technical Information of China (English)
殷明星; 谢勇
2011-01-01
利用Matlab/Simulink工具箱对500 W移相全桥(phase shift full bridge,PSFB) DC/DC变换器建立仿真模型,分别采用传统的PID、模糊PID、神经网络PID等控制方式对系统进行仿真.仿真结果表明:模糊PID和神经网络PID控制方式在调节时间、负载突变等情况下的性能均明显优于传统的PID控制方式.%A simulation model of a 500 watts PSFB (phase shift full bridge) DC/DC converter is established by using the Simulink toolbox in Matlab. The traditional PID control strategy, fuzzy PID control strategy, neural network PID control strategy have been used to simulate the model individually. The simulation results prove that fuzzy PID control strategy and neural network PID control strategy are superior to the traditional PID control strategy in regulation time and the features when the abrupt load change occurs.
Codimension-Two Big-Bang Bifurcation in a ZAD-Controlled Boost DC-DC Converter
Amador, A.; Casanova, S.; Granada, H. A.; Olivar, G.; Hurtado, J.
In this paper, we study some nonlinear behaviors in a two-dimensional system defined by a Boost Converter controlled by CPWM (Centered Pulse-Width Modulation) and a ZAD (Zero Average Dynamics) strategy. The dynamics was analyzed using a discrete-time map, which consists of a sampled system at each switching cycle. The structure of the two-parametric space is characterized analytically. This allows proving the existence and stability of an infinite number of codimension-one curves that intersect at the same point in the two-parametric space. This phenomenon has been called a big-bang bifurcation.
Double-input DC/DC Converter of Wind/PV Hybrid%风光互补双输入DC/DC变换器研究
Institute of Scientific and Technical Information of China (English)
张兴进; 沈锦飞; 曹沛
2011-01-01
According to some problems of the wind/PV hybrid system, such as efficiency, cost, when the wind and PV power energy synthesize, the principle of the proposed double-input DC/DC converter is studied.This paper analyzes different working states of the converter and current fluctuation of inductance L, the core energy storage device of the main circuit.The relationship among input voltage, current, duty ratios and output voltage, current can be obtained by steady-state analysis. A new driving method called alternate working is proposed. Using this method, series connection of wind power and PV cells is avoided,and efficiency of the system is improved.Theoretical arithmetic shows that this method can reduce the current fluctuation of inductance.At last the simulation and experimental results are proposed.%针对目前风光瓦补系统中风电和光电在能量合成时能量利用率低的问题,研究了双输入DC/DC变换器.分析了主电路工作状态和核心储能元件电感上的电流波动大小,通过静态分析得出输入电压、电流、占空比及输出电压、电流之间的关系.提出了交替工作的驱动方法,避免了风电和光伏电池的串联,提高了能量利用率.理论计算表明,相对于同时关断,该方法能够减小电感上的电流波动.最后给出仿真与实验结果.
Institute of Scientific and Technical Information of China (English)
包军林; 孙明; 庄奕琪; 于鹏; 任泽亮
2012-01-01
Optoelectronic coupled device (OCD) is a key element of DC/DC converter. The random increase of low frequency noise (LFN) is one of the main failure modes of DC/DC converter. Effective test method and standard for LFN of photoelectric coupler are absent in China. In this paper, characteristics of low frequency noise in OCD and its generation mechanism were investigated in detail. Bias circuit, equipment and method for LFN measurement were proposed. Experimental results from OCD 4N47 in DC/DC converter demonstrated that the proposed method could be used for accurate measurement of low frequency noise of OCDs, providing an effective approach to evaluating typical faults and system suitability of optoelectronic coupler for DC/DC converter.%光电耦合器是DC/DC电源的关键器件,光电耦合器低频噪声的随机增大是该类电源主要失效模式之一.目前,国内尚未形成光电耦合器低频噪声的有效测试方法,更未建立相关标准.文章详细分析了光电耦合器低频噪声特性及产生机理,提出了其低频噪声测试的偏置电路、测试设备和测试方法.针对用于DC/DC电源的典型光电耦合器(4N47)的实测结果表明,该方法能够准确测试光电耦合器的低频噪声,为DC/DC电源用光电耦合器的系统适用性和典型故障提供了一种有效的评估方法.
Principle analysis of low-voltage high current DC-DC converter%低压大电流DC-DC变换器原理分析
Institute of Scientific and Technical Information of China (English)
张雪圆; 张维戈; 李景新; 路其龙
2012-01-01
主要介绍的是应用于电池放电中的低压大电流DC-DC变换器.首先,就其工作原理做了详细的分析说明,在此基础上,进行了仿真和实验,并对结果进行了分析.可以得出本拓扑适合应用在低压大电流的结构中.与之前广泛应用的能量从半桥侧传递到倍流侧不同,其重点在于将倍流拓扑当作双Boost拓扑进行放电,即能量从倍流侧传递到半桥侧,可实现输入输出电压相差倍数大,而且最大限度地提高了放电的效辜.%A low-voltage and high current DC-DC converter applied to battery discharge was introduced. Firstly, the work elements of the convenor were analyzed in detail, on the basic of it, a lot of simulations and experiments were carried out, and the result was analyzed at last. The analyzing results show that this topology is appropriate to be used at low-voltage and high current construction. Most of the previous papers introduced the construction which the energy passed from the half-bridge side to double current side; on contrast, in this paper the double current topology as double boost topology was discharge. In another word, the energy passed from double current side to half-bridge side, which could realize that the input voltage differed greatly with the output voltage, and improved the discharge efficiency in maximum limit
Design of a Miniaturized Dual Output DC/DC Converter%一种双路输出DC/DC变换器小型化设计
Institute of Scientific and Technical Information of China (English)
何颖; 李江达; 张晖
2014-01-01
Currently, the switch power supply to small, light weight and high efficiency characteristics are widely used in almost all electronic devices. Power systems are often referred to as"the heart of system"with other systems incomparable importance. With the development of science and technology, a variety of electrical equipment systems for the power supply are also increasing, power equipment system components directly affects the size, weight and reliability. In this paper, a miniaturized dual output isolated DC/DC converter as a design example, through the analysis of the actual circuit, a detailed description of its working principle and the main components of the value or calculation methods are also explainned.%目前，开关电源以小型、轻量和高效率等特点被广泛应用于几乎所有的电子设备，电源系统通常被称为“心脏系统”，有着其他系统不可比拟的重要地位。随着科学技术的发展，各种用电装备系统对于电源的要求也越来越高，电源组件直接影响着装备系统的体积、重量和可靠性。文章以一个小型化隔离型双路输出DC/DC变换器作为设计实例，通过对实际电路的分析，详细说明其工作原理及主要器件的取值或计算方法。
Institute of Scientific and Technical Information of China (English)
刘福鑫; 潘子周; 阮新波
2013-01-01
The conventional dual active bridge (DAB) dc/dc converter can be appropriate for the systems with bidirectional power flow, but its output and input currents are discontinuous. Therefore, a boost-integrated DAB converter of which output and input currents are continuous was proposed in this paper. The proposed converter has the advantages of symmetrical structure, galvanic isolation and simple control strategy, and it is suitable for the applications with low current ripple requirement. This paper described the operation principle and zero-voltage-switching (ZVS) condition of the converter in detail. Specially, the ZVS condition was deduced on the basis of particular calculation of the resonant interval that occurs at the moment of switching, which is in consideration of the junction capacitors of switches. Finally, a 1 kW prototype converter had been built to verify the theoretical analysis.%传统双向桥式直流变换器可应用于能量双向传递供电系统中,但其输入输出电流断续.为此提出一种输入输出电流连续且可实现软开关的Boost型双向桥式变换器,该变换器具有结构对称、电气隔离和控制简单等优点,适用于输入输出电流脉动较小的应用场合.介绍该变换器的工作原理,且详细分析开关管电压和电流在开关过程中的变化情况,并据此推导出在考虑结电容影响时开关管实现零电压开关的条件.最后通过一台1kW的原理样机对理论分析进行验证.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2013-01-01
-on of active switches and zero-current switching (ZCS) turn-off of diodes. In this paper, derivation, analysis and design of the proposed converter are presented. Finally, a 25~50 V input, 300~400 V output prototype with a 600 W nominal power rating is built up and tested to demonstrate the effectiveness...... for various applications, such as fuel cell and super-capacitor hybrid energy system. By fully using two high frequency transformers and a shared leg of switches, number of the power devices and associated gate driver circuits can be reduced. With phase-shift control, the converter can achieve ZVS turn...
DEFF Research Database (Denmark)
Thummala, Prasanth; Maksimovic, Dragan; Zhang, Zhe;
2016-01-01
on the output high-voltage (HV) side. Experimental results verifying the bidirectional operation of a high voltage flyback converter are presented, using a 3 kV polypropylene film capacitor as the load. The energy loss distributions of the converter when 4 kV and 4.5 kV HV MOSFETs are used on HV side...... are presented. The flyback prototype with a 4 kV MOSFET demonstrated 89% charge energy efficiency to charge the capacitive load from 0 V to 2.5 kV, and 84% discharge energy efficiency to discharge it from 2.5 kV to 0 V, respectively....
DC-DC powering for the CMS pixel upgrade
Feld, Lutz; Fleck, Martin; Friedrichs, Marcel; Hensch, Richard; Karpinski, Waclaw; Klein, Katja; Rittich, David; Sammet, Jan; Wlochal, Michael
2013-12-01
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&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 to 24 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.
DC-DC Powering for the CMS Pixel Upgrade
Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Rittich, David Michael; Sammet, Jan Domenik; Wlochal, Michael
2013-01-01
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.
高效率高增益Boost-Flyback直流变换器%High Efficiency High Step-up Boost-Flyback DC/DC Converter
Institute of Scientific and Technical Information of China (English)
吴红飞; 古俊银; 张君君; 邢岩; 陈国呈
2011-01-01
提出一种基于Boost拓扑与反激拓扑有机组合思想的Boost-Flyback变换器，Boost环节与反激环节共用输入支路，使电感一变压器的漏感能量得以利用，消除了漏感损耗，并实现了开关管电压钳位，减小了开关管电压应力；Boost与反激环节的输出支路串联，实现了高电压增益；Boost-Flybaek变换器输入并联输出串联，进一步提高了变换器的电压增益，同时减小了输入输出电压及电流纹波。提出新拓扑的DCM-ZVS工作模式控制方法，并在开环方式下实现了输出功率的控制。详细分析拓扑的工作原理、电压增益特性及控制方%A novel Boost-Flyback converter was proposed based on the combination of Boost and Flyback topologies. The energy stored in the leakage inductance of transformer is recycled and the active switch turn-off voltage is clamped by sharing the branch of the input side of the two topologies mentioned. High voltage gain is achieved with the output of Boost and Flyback topologies connected in series. The voltage gain of the converter is further improved with two of the Boost-Flybaek topologies proposed in input-in-parallel output-in-series connected. Devices stress, output and input voltage/current ripple are reduced. An output power control and discontinued current mode-zero voltage switching （DCM-ZVS） control were proposed also. The operational principle, voltage gain characteristics and principle of DCM-ZVS control method were analyzed in detail. The experimental results based on a 230 W 30 to 380 V DC/DC prototype verify the effectiveness of the theoretical analysis.
多端口背靠背式直流-直流换流系统%Multiport Back-to-back dc-dc Converting Systems
Institute of Scientific and Technical Information of China (English)
苗璐; 林卫星; 姚良忠; 孙蔚; 劲宇
2015-01-01
提出一种多端口背靠背式直流–直流换流系统(multiport back-to-back，MB2B)。其内部由多个电压源型换流器(voltage source converters，VSC)组成，VSC交流侧均连接到MB2B内部公共交流母线。为了使MB2B具有联接不同电压等级直流线路的功能，MB2B内部采用变压器来匹配不同电压等级的直流线路。MB2B的每个端口均可独立调节其潮流。为了减少VSC运行损耗，MB2B内部交流系统运行频率取为工频。详细设计 MB2B 的稳态控制及故障下功率自动平衡控制。为验证该拓扑的可行性和安全性，在PSCAD/EMTDC上搭建由四端口MB2B构成的实验电网系统的仿真模型，并针对该实验系统进行黑启动、潮流调节、直流故障隔离以及故障下自动功率平衡等仿真。实验系统中所有的控制策略均不需要任何通讯。%This paper proposed a multiport back-to-back dc-dc converting system (MB2B). The multiport consists of multiple voltage source converters (VSC), and an independent inner ac circuit, which is used to interconnect the ac side of multiple VSC converters. In order to enable multiport MB2B interconnecting multiple dc lines with different dc voltages, transformers are used for voltage matching of different voltage levels. Each port of the MB2B could control its power flow independently. In order to reduce the power loss of the VSC converters, the inner ac circuit is operated at the grid frequency. Controllers of each VSC converter and automatic power rebalance control of the grid were designed in this paper. A laboratory-scale four-terminal dc grid constructed by a four-port MB2B is used to test the necessity, feasibility and security of the multi MB2B. Simulations of the start-up process, power flow control, dc fault isolation and automatic power rebalance validated the feasibility and advantages of the MB2B. All of the controllers in the dc grid are achieved without requiring any telecommunication.
Optimization of Inductance for Buck DC-DC Converter%Buck DC-DC变换器电感的优化设计
Institute of Scientific and Technical Information of China (English)
付园园; 姚素英; 徐江涛; 高静; 陈莞
2012-01-01
提出了一种优化电感的设计方法,以最小的电感实现了Buck DC-DC变换器最大输出纹波电压(MOVR)达到极小值.该方法首先通过计算得到连续导电模式(CCM)和不连续导电模式(DCM)下的输出纹波电压,然后根据电感取值分析这两种模式下的MOVR,最终得到了使MOVR达到极小值的最小电感.分析得到,对于任意给定的输入电压和负载范围,计算最大输入电压、最小负载下CCM和DCM模式的临界电感和最小输入电压、最大负载下的临界电感,则最优电感为两者中的较大值.Pspice仿真结果验证了上述理论分析的正确性,开关频率为52 kHz,输出电压12 V时,对于给定输入电压范围15～21V,负载范围35～170 Ω,最优电感为327μH.%In order to realize the lowest maximum output voltage ripple (MOVR) of Buck DC-DC converter with the minimal inductance, an optimal inductance design method is proposed. Output voltage, ripple (OVR) under continuous conduction mode (CCM) and discontinuous mode (DCM) was obtained by calculation, then MOVR in the two modes was analyzed according to the inductance value, and ultimately the minimum inductance to achieve the lowest MOVR was obtained. For any given range of the load and input voltage, by comparing the critical inductance between CCM and DCM under the maximum input voltage, minimum load condition and under the minimum input voltage, maximum load condition, it is concluded that the minimum inductance to guarantee the lowest MOVR is actually the maximum value of the critical inductance under the two conditions. The Pspice simulation results are in favor of the proposed theory.
一种基于STD的Buck变换器滑模控制%A STD Based Sliding Mode Control Design for DC-DC Buck Converter
Institute of Scientific and Technical Information of China (English)
皇甫宜耿; 卓生荣; 王小飞; 蒋康博
2016-01-01
针对新能源用DC⁃DC Buck变换器常规滑模控制需要同时检测变换器输出电压和滤波电容电流，提出一种基于super⁃twisting微分器（ STD）的滑模控制器。与常规滑模控制器相比，所提出的控制方法只需检测变换器输出电压，无需测量电容电流，因此可以将电流传感器从控制环路中移除，从而简化控制系统。仿真实验结果表明，与常规滑模控制器相比，所提出的STD滑模控制具有更小的稳态误差，同时保留了对输入电压扰动和输出负载扰动的强鲁棒性。%The conventional sliding mode control design for DC⁃DC buck converter needs to measure the converter output voltage and the capacitor current simultaneously. In contrast to this, the paper proposes an innovative super⁃twisting differentiator ( STD) based sliding mode control for DC⁃DC buck converter. The STD based sliding mode control only needs to measure the converter output voltage. There is no need to measure the capacitor current, such that the current sensor can be removed from the control loop, thus the control system is simplified. It has been dem⁃onstrated by simulation results that when compared with conventional sliding mode control, the proposed STD sliding mode control can achieve smaller steady state voltage error and at the same time, the strong robustness a⁃gainst the input voltage perturbation and load resistance disturbance can also be preserved.
Institute of Scientific and Technical Information of China (English)
邱力军; 杨威; 王荣; 王伊笑
2015-01-01
In this paper the working principle of active clamp forward converter and the features of LM5026 chip were proposed. Furthermore, an example was proposed to discuss the design of transformer and inductor in active-clamp DC-DC converter. In the design example, efficiency of higher than 90%and the load regulation within 1%were obtained for an input of 28V and the implementation of the soft switch of the main MOSFET was realized, verifying the excellent load regulation and high efficiency of the active-clamp forward DC-DC converter.%介绍了有源钳位正激变换器的工作原理以及 LM5026芯片的功能特点，并以一个设计实例讨论了变压器和电感在有源钳位DC-DC变换器中的设计。结果表明，在28V 输入电压时，效率超过90%，负载调整率也在1%以内，且实现了主MOS管的软开通，验证了有源钳位正激变换器良好的负载调整率以及高效性。
Institute of Scientific and Technical Information of China (English)
李鑫; 解璞
2016-01-01
独立光伏系统中，储能环节起到平衡功率、稳定系统的关键作用，而合理的控制策略能将储能系统与光伏阵列有机地结合起来，双向 DC/DC变换器正是完成此目标的桥梁。本文在对已有的双向 DC/DC变换器进行优化设计的基础上，提出了一种兼顾电池电性能与系统稳定性的储能系统控制策略。在 Matlab仿真环境下搭建了带有双向 DC/DC变换器的独立光伏系统模型，并对储能系统的工作情况进行仿真，验证了变换器拓扑结构与储能控制策略的合理性。%The independent photovoltaic system needs energy storage in order to balance the power and improve its stability of power generation. A scientiifc control strategy can combine the PV cells with the battery system organically. The bi-directional DC/DC converter can be the bridge to achieve this target. This paper presents a control strategy which takes account of battery electrical performance and system stability based on optimization on the circuit topology of bi-directional DC/DC already underway. Moreover, the charge and discharge circuit based on bi-directional DC/DC converter and an integral independent PV power system are built with Matlab. The simulation results show the correctness of the charge and discharge circuit topology and control strategy.
Institute of Scientific and Technical Information of China (English)
唐伟; 付晗
2011-01-01
DC-DC converter for solar photovoltaic power generation is used to boost the voltage at DC side of the inverter.Full bridge structure have the characteristics such as low rate voltage power switch,high efficiency of the transformer,advantage to soft-switching.Standard full-bridge DC-DC converter is designed in series-connected versions and their operation has been evaluated in simulation.The result shows that the switches peak current can be significantly reduced,thus the costs can be reduced and the energy source utilization can be improved.%光伏发电系统中DC-DC变换器的作用是使太阳能光伏电池电压达到光伏系统逆变环节的直流母线电压的要求。其中,全桥结构具有功率开关管电压应力小、变压器利用率高、容易实现软开关的特点,现将标准的全桥DC-DC变换器重新设计成串联形式,用计算机仿真来评估其工作状况,结果表明,开关的工作峰值电流被显著地减小了,减少了损耗并提高了电源的利用率。
New series half-bridge converters with the balance input split capacitor voltages
Lin, Bor-Ren; Chiang, Huann-Keng; Wang, Shang-Lun
2016-03-01
This article presents a new dc/dc converter to perform the main functions of zero voltage switching (ZWS), low converter size, high switching frequency and low-voltage stress. Metal-oxide-semiconductor field-effect transistors (MOSFETs) with high switching frequency are used to reduce the converter size and increase circuit efficiency. To overcome low-voltage stress and high turn-on resistance of MOSFETs, the series half-bridge topology is adopted in the proposed converter. Hence, the low-voltage stress MOSFETs can be used for medium-input voltage applications. The asymmetric pulse-width modulation is used to generate the gating signals and achieve the ZWS. On the secondary side, the parallel connection of two diode rectifiers is adopted to reduce the current rating of passive components. On the primary side, the series connection of two transformers is used to balance two output inductor currents. Two flying capacitors are used to automatically balance the input split capacitor voltages. Finally, experiments with 1000 W rated power are performed to verify the theoretical analysis and the effectiveness of proposed converter.
Institute of Scientific and Technical Information of China (English)
李林
2011-01-01
Parallel Input Parallel Output DC-DC converter can reduce the switching switch stress,for high input voltage,low output voltage, high current, high-power welding system. This paper analyzes the switch inverter circuit topology development, parallel input parallel output of the working principle of DC-DC converter,are analyzed in parallel converter current control method. Work exists for its uneven flow phenomena,through the converter output current sampling and comparison to control IGBT＇s conduction time(duty cycle) to achieve current sharing. Through theoretical analysis and simulation verify the feasibility of the above methods, tests show that the output DC voltage ripple, output DC voltage of high quality.%输入/输出并联型直流变换器能降低开关管的开关应力,适用于高输入电压、低输出电压、大电流、大功率的焊接系统.分析了逆变电路拓扑结构开关管发展,输入/精出并联直流变换器的工作原理,重点分析了并联变换器均流控制的方法.针对其工作时存在不均流现象,通过对各变换器的输出电流采样并比较后去控制IGBT的导通时间(占空比)来达到均流.通过理论分析和仿真试验脸证以上方法的可行性,试验表明输出直流电压的纹波小、质量高.
Analysis and Design of Two-stage Isolated Bi-directional DC/DC Converter%一种两级式隔离型双向DC/DC变换器的分析与设计
Institute of Scientific and Technical Information of China (English)
张东; 王一军
2016-01-01
A two-stage isolated bi-directional DC/DC converter is proposed. The converter is composed of a regulated front-end DC/DC converter and a unregulated back-end LLC resonant converter. When the energy flows from low-voltage DC bus to high-voltage DC bus, the converter is equivalent to Boost converter cascaded full bridge LLC resonant converter with output voltage doubling. When the energy flow is reversed, the converter is equivalent to half bridge LLC resonant converter cascaded Buck converter. The operational theory and key design point are analyzed, and efficiency-oriented optimization method of middle-voltage DC bus is proposed. A prototype of 1kW, 12 V/336 V is build, and the optimum nominal voltage of middle-voltage DC bus is 50 V. The experimental results verify the good performance of the proposed converter.%提出了一种两级式隔离型双向DC/DC变换器，该变换器包含一个闭环的前级DC/DC变换器和一个开环的后级LLC谐振变换器。当能量从低压直流母线传输到高压直流母线时，变换器等效为Boost变换器+全桥倍压LLC谐振变换器；当能量反方向流动时，变换器等效为半桥LLC谐振变换器+Buck变换器。通过分析变换器工作原理与设计要点，提出了以效率为目标的中间直流母线电压优化方法，并研制了1台12 V/336 V、1 kW的样机，其优化后的中间直流母线电压额定值为50 V。样机实验结果验证了所提变换器的良好工作性能。
Institute of Scientific and Technical Information of China (English)
常昌远; 陈瑶; 黄金峰; 王青
2012-01-01
A simplified fuzzy control algorithm used for digitally controlled DC-DC converters, the single input fuzzy control algorithm, is proposed. In this algorithm, the signed distance method is introduced to simplify the two inputs in the conventional fuzzy control algorithm to a single input, making the number of the corresponding fuzzy rules significantly reduced. On this basis, the single input fuzzy controller is designed by the field-programmable gate array (FPGA), and the final verification is performed. The experimental results show that for the Buck DC-DC switching converter, when the input voltage is 2.7 to 3.5 V and the output voltage is 0. 8 to 1.5 V, the set-up time is less than 150 ms and the steady-state error is less than 10 mV. Compared with the conventional fuzzy controller, the single input fuzzy controller has simpler hardware implementation in design, regulation and implementation. Therefore, it may be widely used in digitally controlled DC-DC converters.%提出了一种简化的用于数字控制DC-DC变换器的模糊控制算法——单输入模糊控制算法.通过在算法中引入符号距离法,将常规模糊控制算法中的2个输入简化为单个输入,从而使相应的模糊规则条数明显减少.在此基础上,采用FPGA设计了单输入模糊控制器,并进行了系统验证.测试结果表明,在输入电压为2.7～3.5V、输出电压为0.8～1.5V的Buck型DC-DC开关变换器中,系统的建立时间小于150 ms,稳态误差小于10 mV.与常规模糊控制器相比,这种单输入模糊控制器具有设计、调节和硬件实现简单等优势,因而有望在数字控制DC-DC变换器中得到广泛应用.
Design of Oscillator of DC/DC Converter%DC/DC转换器中振荡器电路设计
Institute of Scientific and Technical Information of China (English)
郭庆武; 令文生; 张小峰
2011-01-01
振荡器是DC/DC的重要部件,采用双比较器的是振荡器恒流充放电的张弛振荡器.该振荡器输出方波和锯齿波,由恒定电流源、电容、比较器、RS触发器等组成.为了提高比较器的速度,专门在电路中跨接了一个二极管连接的NMOS管.为了减少对基准电压电路的影响,专门设计了独特的基极电流补偿电路.%Oscillator is an important component of the DC/DC, the oscillator is relaxation oscillator of double comparator and constant current charging and discharging. The output is pulse and sawtooth wave, it is made up of constant current source, capacitance, comparator, RS flip-flops, etc. In order to improve the speed of the comparator, a diode connected NMOS in the circuit is added. In order to reduce the impact on the reference voltage circuit,a unique base current compensation circuit is designed.
DC-DC conversion powering for the CMS tracker at SLHC
Energy Technology Data Exchange (ETDEWEB)
Feld, L., E-mail: Lutz.Feld@cern.c [RWTH Aachen University, Sommerfeldstrasse 14, D-52074 Aachen (Germany); Jussen, R.; Karpinski, W.; Klein, K.; Merz, J.; Sammet, J. [RWTH Aachen University, Sommerfeldstrasse 14, D-52074 Aachen (Germany)
2011-02-01
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.
The DC-DC Conversion Power System of the CMS Phase-1 Pixel Upgrade
Klein, Katja
2014-01-01
The power system of the Phase-1 pixel detector will be described and the performance of the new components, including DC-DC converters, DC-DC converter motherboards and various power distribution boards, will be detailed. The outcome of system tests in terms of electrical behaviour, thermal management and pixel module performance will be discussed.
A DC-DC Conversion Powering Scheme for the CMS Phase-1 Pixel Upgrade
Feld, Lutz Werner; Marcel Friedrichs; Richard Hensch; Karpinski, Waclaw; Klein, Katja; Sammet, Jan Domenik; Wlochal, Michael
2012-01-01
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...
DC-DC Conversion Powering for the CMS Tracker at SLHC
Feld, Lutz
2010-01-01
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.
Institute of Scientific and Technical Information of China (English)
吴云亚; 谢少军; 阚加荣; 汤雨
2014-01-01
根据导抗网络的基本特性，提出一种新型双向直流变换器(bidirectional DC/DC converter，BDC)。分析了所提双向变换器在 boost 模式和 buck 模式下电路的工作模态。由导抗网络的基本特性可知，在任意的工作模式下，都可保证变换器中全桥变换器交流侧的功率因数为1，可使回流功率为零以提高系统效率。分析了双向变换器中的物理量关系，给出了变换器中变压器、导抗网络参数优化设计的规则，提出了双向变换器的信号调制策略及相应控制策略。实验结果表明所提BDC性能优良。%According to basic characteristic of immittance network, a structure for a new type of bidirectional DC/DC (BDC) converter is proposed. The operating modals of the circuit of the proposed BDC converter under boost mode and buck mode are analyzed. It can be seen from basic characteristic of immittance network that under arbitrary working mode the power factor at the AC side of the full-bridge converter in the BDC converter can be ensured as unity, thus it makes the backflow becoming zero to improve the system efficiency. The relation among physical quantities in the proposed BDC converter is analyzed and the rules for optimization design of parameters of transformer and immittance network of the proposed BDC converter are given. The signal modulation strategy of the BDC converter and corresponding control strategy are put forward. Experimental results show that the proposed BDC converter possesses high performance.
基于DPA426R的开关电源环路补偿设计%Loop compensation design of DC/DC converter based on DPA426R
Institute of Scientific and Technical Information of China (English)
王斌
2012-01-01
针对基于集成电源管理芯片DPA426R的正激DC/DC变换器,研究了反馈控制环路的补偿设计方法.建立了开关电源闭环系统的s域传递函数模型,通过调整误差放大电路、光耦反馈电路、DPA426R控制电路等各个环节的电路参数来实现系统零极点的配置.反馈补偿设计无需改变系统的硬件电路结构,在配置零极点时有很大的灵活性,可以获得充足的环路设计裕量.应用Matlab仿真软件结合具体电路参数进行了系统的频域响应分析,仿真实验结果验证了反馈环路补偿设计的有效性.%A high frequency DC/DC converter was designed utilizing the integrated power management IC DPA426R. An approach to feedback control loop compensation was presented. The small signal model of the closed-loop control system for the DC/DC switching power supply in s-domain was built. The circuit parameters of the error amplifier, optocoupler and DPA426 were regulated, in order to realize the pole-zero configurations of the com pensation networks. The loop compensation was designed without changing the hardware circuit structure. The sufficient margin was achieved in the design of the feedback loop. A bode plot of the overall system was generated. The simulation results are shown to verify the validity of the loop compensation approach.
Institute of Scientific and Technical Information of China (English)
孙大鹰; 徐申; 孙伟锋; 陆生礼
2014-01-01
为了提高数字DC-DC变换器的瞬态响应性能，设计了一种基于数字预测控制方法的模糊PID控制器。该控制器根据Buck型DC-DC变换器的电路结构，准确预测单个开关周期或多个开关周期后的负载电压和电感电流，以克服环路时延对系统瞬态响应的影响；同时，在基本PID控制基础上引入模糊控制，实时在线调整PID控制参数，以克服变换器的非线性特性对瞬态能力的影响。所设计数字控制器经FPGA验证，结果表明，与基本PID控制相比，所设计数字预测模糊PID控制器能有效提高变换器的瞬态响应能力，变换器的瞬态响应时间缩短1/3，电压超调量小于5％。%To improve the transient response of digital DC-DC converter,a digital fuzzy proportion-al-integral-derivative (PID)controller with a prediction algorithm is proposed.In the digital control-ler,the output voltage and inductance current after one cycle or multiple cycles are predicted accu-rately based on the circuit structure of Buck DC-DC converter,which overcomes the influence of loop time delay on the transient response.Meanwhile,fuzzy control is introduced in the basic PID control to overcome the influence of the nonlinear characteristics of converter on the transient re-sponse through the real-time online regulation of PID control parameters.The proposed digital con-troller is implemented by the field programmable gate array (FPGA ).The results of verification show that the proposed controller can effectively improve the transient response of converter com-pared with basic PID control.The transient response time of converter can decrease by one third and the voltage overshoot is less than 5%.
Institute of Scientific and Technical Information of China (English)
陈良亮; 尹宏旭; 周斌; 张浩; 丁志刚
2011-01-01
Series resonant DC/DC converter based on variable-frequency control has such advantages as simple topology structure, ZVS for switching MOSFETs in all input voltage and full load range, ZCS for output rectifier diodes and high efficiency, thus this converter is currently one of the research hotspots in switching power converters in the world. The principle of series resonant DC/DC converter is analyzed firstly, and the converter’s characteristics under three kinds of working frequencies are also described in this paper, and the relationship between such parameters as input voltage, output voltage, switching frequency and resonant inductor of this converter under different conditions is also quantitatively provided. Experimental results on a 1.5KW prototype verified that a 96.3％ conversion efficiency can be achieved, all switching MOSFETs realized ZVS, and the relationship between such parameters as input voltage and output voltage is consistent with theoretical analysis. In addition, the experimental waveforms are also consistent with simulation waveforms in this paper.%串联谐振DC/DC变换器具有电路结构简单、在全输入和全负载范围内可实现开关管的zVs、功率转换效率高等优点,是目前开关电源研究的热点之一.本文分析了基于变频控制的串联谐振DC/DC变换器的工作原理,阐明了变换器在三种不同开关频率下的工作特性,定量地给出了不同工作状态下变换器的输入电压、输出电压、开关频率以及谐振电感等参数之间的关系式.在一台1.5KW原理样机上的实验结果表明,该变换器变换效率最高可达96.3%,所有开关管实现ZVS,不同工作状态时变换器输入输出电压等参数关系与理论分析一致.
SWITCHED-CAPACITOR BASED STEP-DOWN RESONANT CONVERTERS
Institute of Scientific and Technical Information of China (English)
Y.P.B.Yeung; K.W.E.Cheng; K.K.Law
2001-01-01
A family of switched-capacitor based resonant converters is present.All converters are in step-downmode.By adding different number of switched-capacitor cells,different output voltage conversion ratio can beobtained.All switching devices in the converters operate under zero-current switching.Both high frequencyoperations and high efficiency are possible.
Institute of Scientific and Technical Information of China (English)
郭明明; 沈锦飞
2011-01-01
The switching loss,voltage and current stress of switching device is large and other shortcomings resulting in decrease efficiency of the system,when the traditional photovoltaic DC/DC converters operate in hard switching state.A soft switch Boost converter with simple structure, easy control is proposed which can greatly reduce switching losses and pressure drop of switching device.Finally, simulation and experimental results verify the converter main and auxiliary switch and freewheeling diode can achieve soft switching, thus transmission efficiency of photovoltaic power generation is improved.%针对传统光伏发电DC/DC变换器工作在硬开关状态时,因开关损耗大、开关管所承受的电压电流大等缺点导致的系统效率下降问题,采用了一种软开关Boost变换器,其结构简单,易于控制,大大减少了变换器工作中的开关损耗,并且降低了开关管所承受的压降.最后通过仿真和实验证明变换器的主、辅开关管和续流二极管均能实现软开关,从而提高了光伏发电传输效率.
Zarębski, Janusz; Górecki, Krzysztof
In the paper the influence of cooling conditions of semiconductor devices on the characteristics of a boost converter is considered. The form of the thermal model of semiconductor devices is proposed and some results of calculations and measurements of the characteristics of this converter are shown. The investigations were performed for the selected types of power MOSFETs operating at different cooling conditions.
Institute of Scientific and Technical Information of China (English)
李峰; 魏廷存; 郑宇亮; 郑然
2012-01-01
在高精度数字DC-DC变换器设计中,必须建立变换器功率级的精确模型.通过分析现有功率级离散模型与连续模型的拟合度,建立了拟合程度更高的修正离散功率级模型.为简化数字控制器设计,针对修正离散功率级模型,提出了一种含单一设计参数的数字补偿器设计方法,并分析了该补偿器对系统稳态和瞬态性能的影响.基于Altera Cyclone Ⅲ FPGA开发板,实现了数字Buck变换器,测试结果表明:1.8V输出电压下,电压纹波率小于1％；0.4 A负载电流跳变时,过渡时间为0.22 ms,实验结果证明了修正离散功率级模型的精确性及数字补偿器的有效性.%For high precision design of digital DC-DC converters, it is necessary to establish the accurate discrete model of power stage. A modified discrete model of power stage with high degree of fitting with continuous model in magnitude and phase is built after analyzing the present discrete power stage model. Based on the modified power stage model, a digital compensator with one design parameter is proposed to simplify the design process, and also the steady-state and dynamic performances of converters using this compensator are analyzed. The digital Buck DC-DC converters is implemented on FPGA (Altera Cyclone III), and the experimental results indicate that the output ripple rate is less than 1% for 1.8 V output voltage, the transitional time is 0.22 ms for 0.4 A load step change, and prove the accuracy of modified discrete power stage model and the validity of the proposed digital compensator.This work is supported by National Natural Science Foundation of China (No. 60972157).
Institute of Scientific and Technical Information of China (English)
郑宇亮; 魏廷存; 李峰
2012-01-01
提出了一种应用于数字DC-DC变换器的高精度定点数字控制器的设计方法；在数字控制器的控制率运算中,将浮点数格式的控制参数转化为定点数格式,从而达到简化硬件电路的目的;该设计方法应用于降压型数字DC-DC变换器的设计中,并完成了基于FPGA的测试和验证；在500kHz的开关频率下,输出电压纹波为14mY,对于士0.5A的负载电流跳变,控制器响应时间约为330μs.测试结果表明,该设计方法在保持控制精度的前提下,可简化硬件电路的设计复杂度,并改善系统的瞬态性能.%A design method of high precision fixed-point digital controller, which is applied to digital DC-DC converter, is proposed. In order to simplify the complexity of hardware circuit, the control parameters of floating-point format are converted into fixed-point format during the operation of the digital controller. The design method is applied to digital DC-DC converter, and the testing and verification based on FPGA are accomplished. When switching frequency is 500KHz, output voltage ripple is 14mV, and when load current varies ± 0. 5A, response time of the controller is about 330μs. The test results indicate that this design method not only preserves the control precision but also simplifies the complexity of hardware circuit as well as improves the system transient performances.
A New Multi-channel DC/DC Converter with Two Inputs%一种新的双输入多通道直流变换器
Institute of Scientific and Technical Information of China (English)
黄志翔; 王维俊; 张欢
2013-01-01
Multiple unidirectional and bidirectional DC converters are usually needed in the traditional energy storage unit of the distributed generation system,to realize its function. The paper puts forward a new multi-channel DC converter with two inputs, whose function is equivalent to a DC converter plus a bidirectional DC converter. The working principle of the multi-channel DC converter with two inputs is analyzed,the steady state equation and the energy management method of converter are worked out. Sim-ulation experiment is conducted and the validity of the analysis is verified by using Saber software. It is concluded that the converter not only possesses the advantages of double input DC Buck converter,but makes it possible that renewable energy supply power to storage input source.%在传统的含储能单元分布式供电系统中，一般都需要多个单向直流变换器和双向直流变换器才能实现其功能。提出一种新的双输入多通道直流变换器，它的功能等效于一个单向直流变换器和一个双向直流变换器。分析了双输入多通道直流变换器的工作原理，给出了变换器的稳态关系式以及能量管理方法，并运用Saber软件进行仿真，验证了理论分析的正确性。该直流变换器除具有双输入Buck直流变换器的优点外，还能实现可再生能源向储电输入源充电。
Institute of Scientific and Technical Information of China (English)
茹金平; 陈得友
2016-01-01
为了满足升压型变换器低成本和大功率密度的需求，提出了一种软开关单极隔离型DC-DC变换器。该变换器电路包含一个无损耗缓冲器，通过漏电感固定住开关的电压峰值，从而实现开关的ZVS关断。在失谐状态下，使用Lr-Cr串联谐振电路来实现二极管的ZCS关断。由于磁化电流低，相较于传统的基于反激的变换器，变压器的容量更少。在输出功率250 W和开关频率100 kHz的条件下进行了实际测试，提出的变换器的最大测量效率为97%。%In order to meet the demand of low cost and high power density of the boost converter,a soft switching DC-DC converter with unipolar switching mode is presented. The converter circuit contains a non loss buffer,which is fixed by the leakage inductance of the switch voltage peak,thereby achieving the switch of the ZVS off. In the con⁃dition of failure,the Lr-Cr series resonant circuit is used to realize the ZCS off of the diode. Due to the low magneti⁃zation current,the transformer capacity is less than the traditional fly-back converter. Under the condition of the out⁃put power 250 W and the switching frequency 100 kHz,the maximum efficiency of the converter is 97%.
Institute of Scientific and Technical Information of China (English)
杨玉岗; 李龙华
2013-01-01
In this paper,the maximum peak inductor current in continuous conduction mode and discontinuous conduction mode of staggered parallel magnetic integrated Buck DC-DC converter is analyzed.The maximum peak inductor current worked in the CCM mode is the maximum inductor current within the work range.Ignoring the effects of the voltage ripple,the maximum output short-circuit release energy across the entire operating range is derived.Through comparing the maximum current of the inductor with the minimum ignition current and comparing the maximum output short-circuit more energy is released with the minimum ignition energy of the discharge to arrive the intrinsically safe parallel magnetic integrated Buck DC-DC converter.Based on the requirement of the output intrinsically safe and intrinsically safe within the scope of work,the appropriate range of inductance and capacitance can be obtained.By maximum output short-circuit released energy partial derivatives of inductance and to make it equal to zero,it can be concluded that the best design parameters of inductance and capacitance when maximum output short-circuit released energy to a minimum under the conditions can be given.Experimental results show the analysis is feasible.%对交错并联磁集成变换器的最大电感电流和最大输出短路释放能量进行分析计算.指出采用交错并联磁集成电路能在更好的保证本质安全的前提下实现变换器输出功率的成倍提高.得出了交错并联磁集成Buck变换器的非爆炸性本质安全判据和使得其最大输出短路释放能量最小的最佳电感、电容设计参数.实验结果证明分析方法的可行性.
Institute of Scientific and Technical Information of China (English)
陈道炼; 严斌; 陈峰; 左巧安; 林真
2012-01-01
A circuit configuration and circuit topological family of quasi single-stage unidirectional buck dc-dc converter mode grid-connected inverters with high frequency link are proposed in this paper. Its circuit configuration is composed of the unidirectional isolated buck dc-dc converter and polarity reversal inverting bridge, and its circuit topology includes single-transistor forward, interleaving single-transistor forward, push-pull, push-pull forward, two-transistor forward, interleaving two-transistor forward, half-bridge, and full-bridge mode circuit. The circuit topology, instantaneous current control strategy, steady principle properties, and design criteria for the key circuit parameters were deeply investigated. Taking push-pull forward mode topology as an example, 1 kW 48VDC/220V50 HzAC grid-connected inverter prototype was developed. The research results show that this kind of inverter has the advantages such as high frequency electrical isolation, simple topology, quasi single-stage conversion, high conversion efficiency , the polarity reversal inverting bridge' s power switches having low voltage stress and ZVZCS, high quality grid-connected current etc.%提出准单级单向Buck直流变换器型高频链并网逆变器电路结构与拓扑族.其电路结构是由单向隔离Buck直流变换器和极性反转逆变桥级联构成；其拓扑族包括推挽正激式、双管正激式、并联交错双管正激式、半桥式和全桥式电路.深入分析研究类逆变器的电路拓扑、电流瞬时值控制策略、稳态原理特性和关键电路参数设计准则.以推挽正激式拓扑为例,设计并研制出1kW48VDC/220V50HzAC并网逆变器样机.研究结果表明,此类逆变器具有高频电气隔离、电路结构简洁、准单级功率变换、变换效率高、极性反转逆变桥功率开关电压应力低且为ZVZCS、并网电流质量高等优点.
基于改进 EKF的 DC／DC转换器电感电流观测器%A DC/DC Converter Inductor Current Observer Based on Improved EKF
Institute of Scientific and Technical Information of China (English)
陈晨; 童乔凌; 谢文; 刘政林
2014-01-01
为了减小电磁干扰（Electromagnetic Interference ，EMI）引起的DC/DC转换器输出电压噪声，消除负载变化引起的稳态误差，提出了一种基于改进的扩展卡尔曼滤波器（Extended Kalman filter ，EKF）的电感电流观测器。首先，介绍了Boost型转换器的状态空间方程和扩展卡尔曼滤波器；之后提出负载估算算法，对EKF进行改进。利用改进EK F的输出电压、电感电流和占空比即可估算出实际负载值，从而实时更新改进EK F的参数，使电流观测器可以准确估计电感电流；最后对提出的电流观测器进行了仿真验证。仿真结果表明，在负载突变时，改进EK F可以对EM I引起的输出电压噪声进行有效滤波，同时准确估计电感电流，保证了DC/DC转换器输出电压的准确性。%This paper presents a DC/DC converter inductor current observer based on improved extended Kalman filter ,which can reduce output voltage noise caused by electromagnetic interference and eliminate the steady state error when load changes .Firstly ,the State-space equations of boost DC/DC converter and extended Kalman filter are introduced .Secondly ,the load estimation algorithm is proposed to improve the extended Kalman filter .The improved extended Kalman filter can use output voltage ,inductor current and duty radio to estimate actual load value .Therefore ,the parameters of improved EKF can be updated in real time and current observer can estimate inductor current accurately .Finally ,the validity of the proposed approach has been demonstrated by simulation . The simulation results show that the improved extended Kalman filter can filtering the output voltage noise caused by electromagnetic interference effectively ,and estimate inductor current precisely ,which ensures the accuracy of the output voltage .
Andersson, Martin
2011-01-01
1 SammanfattningCrossControl är ett företag som bland annat tillverkar integrerade datorlösningar. Datorerna drivs normalt med 18-30 VDC och förbrukar som mest 50W. Datorerna säljs till flertalet olika kunder som monterar dem i allt från skogsmaskiner till tåg. I de olika fordonen varierar spänningen i de befintliga elnäten. Detta skapar behovet av att omvandla spänningen till en nivå som datorerna klarar av. En sådan apparat kallas DC/DC-omvandlare. Spänningsomvandling kan utföras genom linj...
Degrenne, Nicolas; Allard, Bruno; Buret, François; Morel, Florent; Adami, Salah-Eddine; Labrousse, Denis
2011-01-01
This paper describes and evaluates 3 original step-up converter architectures able to harvest energy from low-voltage and low-power generators. Design and sizing are made according to specifications issued from the stringent characteristics of microbial fuel cells. The maximum harvested power is 10mW under input voltage Vin=0.3V (33mA input current). The considered converters include self-oscillating circuits for autonomous operation. The 2 first topologies are respectively adapted from boost...
推挽DC-DC变换器平均电流控制研究%Research of Average Current Mode Control Based on Push-pull DC-DC Converter
Institute of Scientific and Technical Information of China (English)
桂存兵; 谢运祥; 谢涛; 陈江辉
2012-01-01
In order to improve the current stability and reliability of the push-pull converter, this paper ana-lyzed the push-pull DC/DC converter operational principle, and on this basis, built its small signal mathe-matical model. With imposing the current-mode dual-loop control strategy into its control system, improved the system dynamic response and protection ability. It has given the design process of the control system of push-pull converter, simulation and experimental research also has been done in the paper. The simulation and experimental results showed that, in view of the push-pull converter, the dual-loop control strategy has got a good dynamic and static control performance.%该文为提高推挽变换器的电流稳定性和系统可靠性,通过分析了DC/DC推挽变换器的工作原理,在此基础上建立了小信号数学模型.并施以电流型双环控制策略,有效的提高系统的动态响应和保护能力.给出了推挽变换器的控制系统的设计过程,并进行了仿真和实验研究,结果表明针对推挽变换器,双环控制策略具有良好动态和静态控制性能.
ZVS隔离型高增益DC/DC变换器%ZVS isolated high step-up DC/DC converter
Institute of Scientific and Technical Information of China (English)
邾玢鑫; 程杉; 谭超
2015-01-01
将传统的L型电流输入隔离型DC/DC变换器与一种DCM (Diode-Capacitor Multiplier)电压增益单元相结合,提出了一种新型ZVS隔离型高增益DC/DC变换器.在继承传统L型电流输入隔离型DC/DC变换器输入电流纹波小、变压器匝数比低等优点的基础上,所提变换器可通过调节DCM增益单元数来调节变换器的输入输出增益比;通过有源箝位电路和漏感的结合,开关均实现了零电压开通,二极管均实现了零电流关断,二极管的反向恢复损耗得到了抑制;借助于所提DCM增益单元,二极管的电压应力以及变压器的绝缘等级得到了有效降低;所有二极管的电压、电流应力均相等,便于散热设计.对变换器的工作原理和性能特点进行了理论分析,并建立了一台输入24 V、输出400 V、功率为200 W的实验样机.实验测试样机最高效率可达95％,验证了理论分析的有效性和正确性.
Energy Technology Data Exchange (ETDEWEB)
Moreira, Angelo Roberto Rodrigues Resende; Caetano, William Douglas; Pires, Igor Amariz; Silva, Arlete Vieira da [Centro Universitario de Belo Horizonte (UnBH), MG (Brazil)], e-mails: angelogalo2005@hotmail.com, wdouglasbh@gmail.com, igor_amariz@yahoo.com.br, arlete.silva@prof.unibh.br
2011-07-01
The square wave series voltage compensator is an equipment used to mitigate voltage sags. In the case of occurrence of a voltage disturbance, the compensator acts generating a square wave voltage to supply the missing voltage. The energy inserted for the compensation is taken from the electrical grid, by a linear source. The purpose of this paper is to present a switching shunt converter instead of a linear one, with the same output parameters in order to increase the power density. This efficiency is demonstrated by simulations. (author)
Institute of Scientific and Technical Information of China (English)
谷雨; 张东来; 朱洪雨; 李悦
2011-01-01
Due to the intensity change of the output voltage on the solar array bus,Boost based bidirectional DC/DC converter is presented for the sake of providing continual and steady output voltage to the load in the entire orbit cycle. Simplicity, high stability and high efficiency are the advantages of this topology, meanwhile, minimum phase system could be achieved by inserting damping network.Conductance control is adopted to achieve better output response, moreover, voltage feedforward ensure the bandwidth of the conductance control invariable.Finally, the bidirectional experimental results under 1.5 kW are presented to verify the performance of the proposed converter and the efficiency of the converter is tested.%由于空间中太阳电池阵输出母线电压变化幅度较大,为保证电源在整个轨道周期内向负载提供持续稳定的电压,提出一种基于Boost拓扑结构的双向DC/DC变换器.该变换器拓扑简单,可靠性高,在大幅减小系统体积与成本的同时提高了系统的效率,并通过引入衰减网络优化Boost变换器为最小相位系统.变换器采用电导控制,并引入电压前馈控制以维持电导控制带宽的恒定.最后通过实验验证了变换器在1.5 kW功率下能量双向流动的工作特性,测试了变换器的效率.
直驱风电系统直/直变换电路的设计与控制%Design and control of DC/DC converter in direct driven wind power system
Institute of Scientific and Technical Information of China (English)
陈荣
2013-01-01
风速低,直驱风电系统发电机输出电压较低；风速高,发电机输出电压又较高.为保证后接并网逆变器的正常运行,需要在整流后设置升压、降压变换电路,以控制施加到并网逆变器上的电源电压.阐述了直驱风电系统直/直变换电路的构成,详细分析了变换电路工作原理与控制方法,设计并构成了实际试验系统.系统实验运行结果表明:具备升降压功能的直/直变换电路可以实现输入电压的升降压变换,能够保证后续逆变器安全稳定运行.%The output voltage of direct driven wind generator is low when wind speed is low, and it is larger when wind speed is higher. The buck/boost converter is needed to promote or decline DC voltage, so as to control the voltage inflicted on the inverter, and ensure the inverter work normally. The constitution of DC/DC converter in direct driven wind generator was expatiated, the operation principle and its control method were analyzed in detail. The testing equipment was designed and worked out. The result of experiment show that, the converter can carry out promoting or declining voltage, and the safety operation of inverter can be guaranteed.