FRACTIONAL ORDER SMC FOR DC-DC BUCK CONVERTER
S. D. Jagdale; R. M. Nagarale
2013-01-01
This paper proposed a fractional order sliding mode control for DC-DC buck converter. The traditionally P, PI and PID type linear controllers are used to control the voltages. The DC-DC buck converter is nonlinear and time variant in nature. To control such system variable structure control based sliding mode controller (SMC) is used. The fractional order sliding mode control method not only eliminates chattering problem of integer order SMC, it gives good transient response of the system. Th...
Buck-boost DC-DC converter with fractional control
Martínez García, Herminio; Grau Saldes, Antoni; Bolea Monte, Yolanda; Martínez González, Rubén
2011-01-01
This paper deals with the fractional modeling of a DC-DC buck-boost converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. Although the modeling and design of the controller is carried out for this particular DC-DC converter, it can be easily extended to other kind of switching converter. In addition, the comparison between integer-order plant/controller and fractional-order plants/controller is...
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.
Charger for NiMH batteries based on buck DC/DC converter
Lap?evi? 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...
Design and Modeling of an Integrated Inductor in a Buck Converter DC-DC
Y. Benhadda; A. Hamid; T. Lebey; M. Derkaoui
2015-01-01
This paper presents the design and modeling of a square inductor for its integration in Buck converter DC-DC. The first, we calculate the value of inductance. The second, we descript our inductor; dimensioning and electrical model. A buck micro converter schematic simulation coupled with ideal and integrated inductor was presented. This conceptual model of the buck is best understood in terms of the relation between current and voltage of the inductor. Finely, we have simulated the electrom...
Design and Modeling of an Integrated Inductor in a Buck Converter DC-DC
Directory of Open Access Journals (Sweden)
Y. Benhadda
2015-06-01
Full Text Available This paper presents the design and modeling of a square inductor for its integration in Buck converter DC-DC. The first, we calculate the value of inductance. The second, we descript our inductor; dimensioning and electrical model. A buck micro converter schematic simulation coupled with ideal and integrated inductor was presented. This conceptual model of the buck is best understood in terms of the relation between current and voltage of the inductor. Finely, we have simulated the electromagnetic effects in two cases. The first case, an inductor in the air, the second case with substrate. Our geometry is created en 3D space dimension.
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.
DEFF Research Database (Denmark)
Pelan, Ovidiu; Cornea, Octavian; Muntean, Nicolae; Blaabjerg, Frede
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...
Controller Design of buck dc/dc converter using neural networks
International Nuclear Information System (INIS)
Nowadays, dc-dc topologies are widely utilized in many industrial applications due to their high efficiency, fast switching actions, low volume and weight and low cost. DC-DC converter is a big family of converters and consist more than thousand of topologies. Buck converter is one of the types of such family and only operates in the step-down mode. Such converter is highly under damped system and contains nonlinearities which lead to oscillations during operation. During last few decades various new control techniques have been investigated and analyzed in order to overcome the developed oscillation in output of this converter. Recently, NNCs (Neural Network Controllers) are gaining popularity in modeling, identification and control of power electronic converters. These controllers are advanced controllers and have fast dynamic behaviour and robustness. The NNCs are nonlinear controllers which enhance the system performance, increase system speed and reduce the system complexity. In this research work, NNCs are designed for Buck topology to minimize uncertainties. The operation of Buck topology with designed NNCs is analyzed during line and load variations and results are compared with results of PI (Proportional and Integral) controller.
Integrated Current-Mode DC-DC Buck Converter with Low-Power Control Circuit
Nam-Soo Kim; Hye-Im Jeong; Chan-Soo Lee
2013-01-01
A low power CMOS control circuit is applied in an integrated DC-DC buck converter. The integrated converter iscomposed of a feedback control circuit and power block with 0.35 ?m CMOS process. A current-sensing circuit isintegrated with the sense-FET method in the control circuit. In the current-sensing circuit, a current-mirror is usedfor a voltage follower in order to reduce power consumption with a smaller chip-size. The N-channel MOS acts asa switching device in the current-sensing circuit...
Reliability-Oriented Design of LC Filter in Buck DC-DC Converter
DEFF Research Database (Denmark)
Liu, Yi; Huang, Meng
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.
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.
DEFF Research Database (Denmark)
Yang, Xi-jun; Qu, Hao; Yao, Chen; Zhang, Ning-yun; Tang, Hou-jun; Chen, Quan; Blaabjerg, Frede
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 is selected as research subject, dedicated for the use of plasma cutting machine of 2×45kW, and the passivity-based control over the converter is analyzed theoretically at first, then simulated by means of...
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 ?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%.
Mari, Federico; Salvo, Ivano; Tronci, Enrico
2011-01-01
Many Embedded Systems are indeed Software Based Control Systems (SBCSs), that is control systems whose controller consists of control software running on a microcontroller device. This motivates investigation on Formal Model Based Design approaches for automatic synthesis of SBCS control software. In previous works we presented an algorithm, along with a tool QKS implementing it, that from a formal model (as a Discrete Time Linear Hybrid System, DTLHS) of the controlled system (plant), implementation specifications (that is, number of bits in the Analog-to-Digital, AD, conversion) and System Level Formal Specifications (that is, safety and liveness requirements for the closed loop system) returns correct-by-construction control software that has a Worst Case Execution Time (WCET) linear in the number of AD bits and meets the given specifications. In this technical report we present full experimental results on using it to synthesize control software for two versions of buck DC-DC converters (single-input and ...
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. PMID:22877744
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.
Analysis of DC-DC Buck converter with chaotic dynamics using Wigner Distribution
LOGAMANI Premalatha
2010-01-01
DC/DC converters exhibit subharmonicsand chaos when the switching action is governed byfeedback control. Since the use of converters isincreasing in Industries for various applications,deeper analysis of the appearance and the nature ofbifurcation is essential to stabilize its output onto adesired periodic solution. Time frequencyrepresentation is helpful in studying the fine structuresof frequency patterns such as sub harmonics and ultraharmonics of chaotic dynamics. This paper analyzesthe c...
A fast novel soft-start circuit for peak current-mode DC—DC buck converters
International Nuclear Information System (INIS)
A fully integrated soft-start circuit for DC—DC buck converters is presented. The proposed high speed soft-start circuit is made of two sections: an overshoot suppression circuit and an inrush current suppression circuit. The overshoot suppression circuit is presented to control the input of the error amplifier to make output voltage limit increase in steps without using an external capacitor. A variable clock signal is adopted in the inrush current suppression circuit to increase the duty cycle of the system and suppress the inrush current. The DC—DC converter with the proposed soft-start circuit has been fabricated with a standard 0.13 ?m CMOS process. Experimental results show that the proposed high speed soft-start circuit has achieved less than 50 ?s start-up time. The inductor current and the output voltage increase smoothly over the whole load range. (semiconductor integrated circuits)
Scientific Electronic Library Online (English)
FABIOLA, ANGULO GARCIA; GERARD, OLIVAR TOST; GUSTAVO ADOLFO, OSORIO LONDOÑO.
2011-04-01
Full Text Available En la última década se ha reportado la estrategia de control Zero Average Dynamics (ZAD) como una alternativa al control de los convertidores de potencia, garantizando frecuencia fija de conmutación y bajo error. Sin embargo la estabilidad del sistema depende fuertemente de la carga, por lo cual no [...] es robusto. Cuando se pierde la estabilidad la frecuencia fija de conmutación se pierde también. En este artículo se presenta la generalización de la técnica ZAD dentro del marco de la teoría de probabilidades. Usando este marco es posible recuperar el ZAD tal como ha sido analizado hasta ahora y se pueden generar nuevas estrategias de control, las cuales son más estables que las usadas en el ZAD. Por este motivo a esta técnica se le ha llamado Generalized Zero Average Dynamics (GZAD). Presentamos algunas simulaciones del GZAD aplicado a un convertidor de potencia reductor. Esta nueva estrategia no puede ser obtenida con el ZAD clásico. Las simulaciones numéricas muestran buen desempeño del controlador con bajo error de regulación y robustez ante cambio en la carga. Abstract in english 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 fixed frequency switching. However, the stability of the controller is highly dependent on the load value, and when the s [...] tability is lost, the fixed frequency switching is lost too. In this paper we generalize ZAD strategy using the probabilities framework through the expectation operator. Thus, we recover classical sliding mode control classical ZAD strategy, and new control methods can be defined, which are more stable than the others previously used. For this reason, this technique is entitled Generalized Zero Average Dynamics (GZAD). We will show several simulations regarding an application to a DC-DC Buck converter within the generalized ZAD strategy, which cannot be deduced from the classical ZAD. Numerical simulations show good regulation features and a wide range of stability.
Loss model for a high frequency and low load DC/DC synchronous buck converter
Díaz López, Daniel; Vasic, Miroslav; García Suárez, Oscar; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; Cobos Márquez, José Antonio
2012-01-01
This work presents a behavioral-analytical hybrid loss model for a buck converter. The model has been designed for a wide operating frequency range up to 4MHz and a low power range (below 20W). It is focused on the switching losses obtained in the power MOSFETs. Main advantages of the model are the fast calculation time and a good accuracy. It has been validated by simulation and experimentally with one Ga, power transistor and two Si MOSFETs. Results show good agreement between measurements ...
Adaptive switching frequency buck DC—DC converter with high-accuracy on-chip current sensor
Jinguang, Jiang; Fei, Huang; Zhihui, Xiong
2015-05-01
A current-mode PWM buck DC—DC converter is proposed. With the high-accuracy on-chip current sensor, the switching frequency can be selected automatically according to load requirements. This method improves efficiency and obtains an excellent transient response. The high accuracy of the current sensor is achieved by a simple switch technique without an amplifier. This has the direct benefit of reducing power dissipation and die size. Additionally, a novel soft-start circuit is presented to avoid the inrush current at the starting up state. Finally, this DC—DC converter is fabricated with the 0.5 ?m standard CMOS process. The chip occupies 3.38 mm2. The accuracy of the proposed current sensor can achieve 99.5% @ 200 mA. Experimental results show that the peak efficiency is 91.8%. The input voltage ranges from 5 to 18 V, while a 2 A load current can be obtained. Project supported by the National Natural Science Foundation of China (No. 41274047), the Natural Science Foundation of Jiangsu Province (No. BK2012639), the Science and Technology Enterprises in Jiangsu Province Technology Innovation Fund (No. BC2012121), and the Changzhou Science and Technology Support (Industrial) Project (No. CE20120074).
International Nuclear Information System (INIS)
This paper presents a width controller, a dead time controller, a discontinuous current mode (DCM) controller and a frequency skipping modulation (FSM) controller for a high frequency high efficiency buck DC-DC converter. To improve the efficiency over a wide load range, especially at high switching frequency, the dead time controller and width controller are applied to enhance the high load efficiency, while the DCM controller and FSM controller are proposed to increase the light load efficiency. The proposed DC-DC converter controllers have been designed and fabricated in the Chartered 0.35 ?m CMOS process, and the measured results show that the efficiency of the buck DC-DC converter is above 80% over a wide load current range from 8 to 570 mA, and the peak efficiency is 86% at 10 MHz switching frequency. (semiconductor integrated circuits)
Morcillo Bastidas, José Daniel
2012-01-01
Los sistemas de baja potencia se utilizan ampliamente en la robótica y en la industria, por lo tanto, el modelado y análisis de sistemas proporcionan fiabilidad y mejores diseños para tales sistemas. El convertidor buck es uno de los sistemas que ha sido ampliamente analizado durante años con el objetivo de conocer su comportamiento y mejorar el diseño de los algoritmos de control. En consecuencia, en este trabajo el convertidor buck controlado por PWM de voltaje es modelado, simulado y estud...
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
A Novel Zero-Voltage-Switching PWM Full Bridge Dc-Dc Buck Converter
Directory of Open Access Journals (Sweden)
Pravin Subhash Pawar *
2014-07-01
Full Text Available Introducing resonant inductance and clamping diodes into the full-bridge converter can eliminate the voltage oscillation across the rectifier diodes and increase the load range for zero-voltage-switching (ZVS achievement. The resonant inductance is shorted and its current keeps constant when the clamping diode is conducting, and the clamping diode is hard turned-off, causing significant reverse recovery loss if the output filter inductance is relatively larger. This paper improves the full-bridge converter by introducing a reset winding in series with the resonant inductance to make the clamping diode current decay rapidly when it conducts. The reset winding not only reduces the conduction losses, but also makes the clamping diodes naturally turn-off and avoids the reverse recovery. As the diodes are turned off naturally and reverse recovery voltage is avoided the distortions caused in the output voltage is removed to a maximum extend by varying the turns ratio of the transformer. The energy stored in the reset winding is also increased by which the inductor value of the snubber circuit to turn off the clamping diodes also increases, which results in reductions in the distortions of the output voltage.
Scientific Electronic Library Online (English)
Marcela, González Valencia; Alfonso, Alzate Gómez.
2010-06-01
Full Text Available Se presenta el diseño estático de un convertidor reductor-elevador bidireccional con tres conmutadores y conexión en cascada. La principal aplicación del convertidor es la administración de baterías en sistemas de alimentación ininterrumpida, controlando el flujo de energía y regulando la tensión de [...] alimentación DC durante los diferentes modos de operación de la batería como fuente y sumidero. Abstract in english This paper shows a buck-boost converter static design with 3 switches and cascade connection. The main application of the converter is the battery management on uninterruptible power supplies, controlling energy flow and regulating the DC supply voltage for the different battery operation modes as s [...] ource and sink.
International Nuclear Information System (INIS)
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 0.35 ?m 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 (semiconductor integrated circuits)
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.
Pulse-width modulated DC-DC power converters
Kazimierczuk, Marian K
2015-01-01
PWM DC-DC power converter technology underpins many energy conversion systems including renewable energy circuits, active power factor correctors, battery chargers, portable devices and LED drivers. Following the success of Pulse-Width Modulated DC-DC Power Converters this second edition has been thoroughly revised and expanded to cover the latest challenges and advances in the field. Key features of 2nd edition: Four new chapters, detailing the latest advances in power conversion, focus on: small-signal model and dynamic characteristics of the buck converter in continuous conduction
DC/DC Converter Stability Testing Study
Wang, Bright L.
2008-01-01
This report presents study results on hybrid DC/DC converter stability testing methods. An input impedance measurement method and a gain/phase margin measurement method were evaluated to be effective to determine front-end oscillation and feedback loop oscillation. In particular, certain channel power levels of converter input noises have been found to have high degree correlation with the gain/phase margins. It becomes a potential new method to evaluate stability levels of all type of DC/DC converters by utilizing the spectral analysis on converter input noises.
Full range ZVS DC-DC converter
International Nuclear Information System (INIS)
A 500 V, 24 Amp DC-DC converter with digital signal processor (DSP) based control and protection has been designed, fabricated and tested. Its power circuit consists of IGBT based single phase inverter bridge, ferrite transformer and diode rectifier. All IGBTs in the inverter bridge are operated in zero voltage switching (ZVS) mode to minimize switching losses thereby increasing the efficiency of the converter significantly. The efficiency of this converter is measured to be greater than 97% at full load. In a conventional full bridge inverter, typically ZVS is achieved under full load condition while at light load ZVS is lost. An auxiliary LC circuit has been intentionally incorporated in this converter to achieve ZVS even at light loaded conditions. Detailed simulation of the converter circuit is carried out and crucial waveforms have been presented in this paper. Microchip make dsPIC30F2020 DSP is employed to provide phase shifted PWMs to IGBTs in the inverter bridge. All the crucial parameters are also monitored by this DSP and in case of any unfavorable conditions, the converter is tripped off. Suitable experiments were carried out in this DC-DC converter under different loaded conditions and a close match between the simulated and experimental results were obtained. Such DC-DC converters can be connected in series or parallel for the development of solid state modular power supplies for various applications. (author)
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
Fractional DC/DC converter in solar-powered electrical generation systems
Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio
2010-01-01
This paper deals with the fractional modelling of a DC-DC buck-boost converter, suitable in solarpowered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. Although the modelling and design of the controller is carried out for this particular DC-DC converter, it can be easily extended to other king of switching converter. In addition, the comparison between integer-order plant/controller and fractiona...
Application handbook for a Standardized Control Module (SCM) for DC-DC converters, volume 1
Lee, F. C.; Mahmoud, M. F.; Yu, Y.
1980-04-01
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.
International Nuclear Information System (INIS)
A high switching frequency voltage-mode buck converter with fast voltage-tracking speed and wide output voltage range has been proposed. A novel error amplifier (EA) is presented to achieve a high DC gain and get high phase margin, including a resistor and capacitor net, a unit gain block and a high gain block. The investigated converter has been fabricated with GF 0.35 ?m CMOS process and can operate at 6 MHz with the output voltage range from 0.6 to 3.4 V. The experimental results show that the voltage-tracking speed can achieve 8.8 ?s/V for up-tracking and 6 ?s/V for down-tracking. Besides, the recovery time is less than 8 ?s while the load current suddenly changes 400 mA. (semiconductor integrated circuits)
HYBRID MODELING OF OPEN LOOP DC-DC CONVERTERS
Directory of Open Access Journals (Sweden)
Ekaitz Zulueta
2003-12-01
Full Text Available Power electronic converters always have been circuits of difficult modelling because differential equations that describe them have discontinuities. Although this situation has been improved since the appearance of the Hybrid Systems theory, able to jointly describe both continuous and discrete behaviors exhibited by some physical systems, nowadays it is possible to obtain very precise models which help us in the study and design of such circuits. An excellent option for the discrete part model (reactive system is to use statecharts, since this powerful language has recently been implemented and named Stateflow as a part of the Simulink toolbox of Matlab. So, today, the complete modeling of some hybrid systems within Matlab environment is possible. In this work the open loop hybrid modeling and simulation of the well-known dc-dc converters named buck and boost, using Matlab-Simulink-Stateflow, is presented
SIMPLIFIED APPROACHES FOR CONTROLLING DC-DC POWER CONVERTERS
Directory of Open Access Journals (Sweden)
M. M. ABDEL AZIZ
2012-02-01
Full Text Available This paper represents the design procedures of different compensation schemes for voltage mode controlled (VMC dc–dc switching converters. Proportional integral derivative (PID controllers, Fuzzy logic controllers (FLC, parallel combination of PID and FLC, and FLC tuned by PI controller have been investigated. MATLAB software is used to depict the buck converter performance with each compensator type when it is electrically simulated, and analytically modeled using its equivalent transfer function (TF. The comparative study Resultsemphasize that FLC tuned by PI controller is superior to the other control strategies because of fast transient response, minimum steady state error and good disturbance rejection under various variations of the operating conditions. Hence, it achieves the most tightly output voltage regulation.
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.
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.
Early Oscillation Detection for DC/DC Converter Fault Diagnosis
Wang, Bright L.
2011-01-01
The electrical power system of a spacecraft plays a very critical role for space mission success. Such a modern power system may contain numerous hybrid DC/DC converters both inside the power system electronics (PSE) units and onboard most of the flight electronics modules. One of the faulty conditions for DC/DC converter that poses serious threats to mission safety is the random occurrence of oscillation related to inherent instability characteristics of the DC/DC converters and design deficiency of the power systems. To ensure the highest reliability of the power system, oscillations in any form shall be promptly detected during part level testing, system integration tests, flight health monitoring, and on-board fault diagnosis. The popular gain/phase margin analysis method is capable of predicting stability levels of DC/DC converters, but it is limited only to verification of designs and to part-level testing on some of the models. This method has to inject noise signals into the control loop circuitry as required, thus, interrupts the DC/DC converter's normal operation and increases risks of degrading and damaging the flight unit. A novel technique to detect oscillations at early stage for flight hybrid DC/DC converters was developed.
Simulation analysis of cascade controller for DC-DC bank converter
International Nuclear Information System (INIS)
Power electronic converters are periodic variable structure systems due to their switched operation. During the last few decades several new dc-dc converter topologies have emerged. Buck converter being simple in topology, has recently drawn attraction of many researchers. Basically, a buck converter is highly underdamped system. In order to overcome the developed oscillations in output of this converter, various control techniques have been proposed. However, these techniques are fraught with many drawbacks. This paper focus on a cascade controller based buck topology. Steady state analysis is given in this paper which shows output voltage and inductor current in detail. Dynamic analysis for line and load variation is also presented. The buck topology is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)
Modified Multiport Dc-Dc Converter Topology For Smart Grid
Dhamodharan Shanmugam
2013-01-01
The development of a Solid State Transformer (SST) that incorporates a DC-DC multiport converter to integrate both photovoltaic (PV) power generation and battery energy storage is presented in this dissertation. The DC-DC stage is based on a quad active-bridge (QAB) converter which not only provides isolation for the load, but also for the PV and storage. The AC-DC stage is implemented with a pulse-widthmodulated (PWM) single phase rectifier. A unified gyrator-based average model is develope...
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.
Soft Commutated Three-Phase Dc-Dc Converter
Directory of Open Access Journals (Sweden)
Silpa.P.T
2014-08-01
Full Text Available High efficient DC-DC Converters find its application in electric power generation, transmission, distribution and Uninterruptable power supplies (UPS. Three phase converter system as compared with single phase converter system increases power density with reduced switching stresses, efficient usage of the transformer magnetic core and smaller filter design as the frequency of the system is higher. Inorder to make use of the above mentioned advantages a ZVS-PWM three- phase current-fed push-pull dc-dc converter with active clamping was developed. This converter topology allows the reuse of the energy from the leakage inductances and reduces the electromagnetic interferences (EMI. The topology was designed and simulated using MATLAB/SIMULINK. The input supply voltage used for the converter is 120V DC.
Hysteretic Current Controlled Zvs Dc/Dc Converter For Automobile
DEFF Research Database (Denmark)
Cernat, M.; Scortarul, P.; Tanase, A.; Iov, Florin
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 curr...
A New Soft-Switched Resonant DC-DC Converter
Pourabbasali, Rogayeh; Freghi, Samira; Pourabbasali, Reza; Pakdel, Majid
2011-01-01
This paper presents a new soft-switched resonant dc-dc converter using a passive snubber circuit. The proposed converter uses a new zero voltage and zero current switching (ZVZCS) strategies to get ZVZCS function. Besides operating at constant frequency, all semiconductor devices operate at soft-switching without additional voltage and current stresses. In order to validate the proposed converter, computer simulations and experimental results were conducted. The paper indicates the effective ...
A new LVI assisted PSFB DC-DC converter
BAKAN, Ahmet Faruk
2011-01-01
In this study, a new Phase Shifted Full Bridge (PSFB) Pulse Width Modulated (PWM) isolated dc-dc converter is proposed. In the proposed converter, resonant inductor is replaced with Linear Variable Inductor (LVI) that is controlled by output current. The soft switching operation range is increased and the dependency of ZVS operation on the load current is decreased. The required energy for ZVS operation at low current levels is obtained by means of the high value of the LVI. The val...
Dynamic Evolution Control for Fuel Cell DC-DC Converter
Ahmad Saudi Samosir; Tole Sutikno; Abdul Halim Mohd Yatim
2011-01-01
Fuel cells are new alternative energy resource that has a great promise for distributed generation and electric vehicle application. However, fuel cells have a slow response due to their slow internal electromechanical and thermodynamic response. To optimize the fuel cell system performance, a fuel cell DC-DC converter with an appropriate controller which can regulate the power flow and automatically adjust the converter output voltage is needed. This paper proposes a new control technique fo...
Implementation of FPGA based Digital Controller for Controlling Chaos in DC/DC converters
Directory of Open Access Journals (Sweden)
RANJAN Vanaja
2010-05-01
Full Text Available This paper analyzes the subharmonics andchaos generated in closed loop pulse width modulatedDC/DC buck converter and suggests the implementationof Digital controller based on time delayed selfcontrolling feedback concept for stabilizing the chaosgenerated in such converter. FPGA based digitalcontroller is designed and implemented for controllingthe chaotic oscillations of nonlinear switching converters.An experimental FPGA prototype and an applicationspecific IC that employ new controller architecture arebuilt around 11.3 V, 5.5 W, 2.5 KHz buck converter stageand successful operation of digital controller is verified.The experimental results prove the inherent capability ofthe proposed controller in maintaining the desired outputvoltage and keep the system chaos free by making thesystem insensitive to parameter variations.
Design Of Vswt With Lcl Resonant Dc-dc Converters For Rl Load
Directory of Open Access Journals (Sweden)
M. Vijaya Kumar
2012-08-01
Full Text Available This paper deals with design of variable speed wind turbine (VSWT with LCL resonantDC-to-DC converter for stand-alone wind energy system with RL load. The wind turbinesystem consists of synchronous generator (SG, full bridge diode rectifier, buck DC- DCconverter and inverter with RL load is present. Based on this electrical model, a Simulinkmodel of the system are simulated by using MATLAB Simulink power system blocks. Thisconverter has advantages like reduced transformer size, reduced filter size and currentsource characteristics. The Simulink circuit model for closed loop system of full bridgeDC – DC converter VSWT is developed and the same is used for simulation studies.
Sliding Mode Control of Buck Converter
Nagulapati Kiran
2014-01-01
DC-DC converters are used to convert DC voltage from one level to other. These converters are drastically used in industry as well as in research. One of the main limitations of these converters is unregulated supply of voltage and current. To overcome these problems there are various control techniques. This paper presents two such methods. This paper compares dynamic performance of buck Converter using PID controller and Sliding mode controller. Simulation of PI and Sliding mode control of ...
DC-DC Converters - Dynamic Model Design and Experimental Verification
Johansson, Bengt
2005-01-01
To obtain high performance control of a dc-dc converter, a good model of the converter is needed. The load usually affects the dynamics and one way to take this into consideration is to regard the load as a part of the converter. The load is often the most variable part of this system. If the load current and the output voltage are measured there are good possibilities to obtain a good model of the load on-line. Adaptive control can then be applied to improve the control. In peak curre...
Multiple Output ZVS DC/DC Converter Based on PWM
Directory of Open Access Journals (Sweden)
Olivia Ramya Chitranjan
2014-05-01
Full Text Available This project presents a soft-switching dc/dc converter with transformers connected in series to implement the features of ZVS, low voltage stress for MOSFETs. The converter has two half-bridge circuits connected in series to limit the voltage stress of MOSFETs at one-half of the input voltage. The output sides of four circuits are connected in series and parallel to primary circuit. The proposed multi output converter shows excellent performance in terms of its output regulation from no-load to full-load conditions and it also provides a multi output capability.
Design and implementation of fully-integrated inductive DC-DC converters in standard CMOS
Wens, Mike
2011-01-01
CMOS DC-DC Converters aims to provide a comprehensive dissertation on the matter of monolithic inductive Direct-Current to Direct-Current (DC-DC) converters. For this purpose seven chapters are defined which will allow the designer to gain specific knowledge on the design and implementation of monolithic inductive DC-DC converters, starting from the very basics.
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.
Scientific Electronic Library Online (English)
Carlos Andrés, Ramos-Paja; Roberto, Gira; Eliana Isabel, Arango Zuluaga.
2012-09-01
Full Text Available Se propone una estructura de desvío activo para maximizar la producción de potencia en sistemas fotovoltaicos bajo condiciones irregulares de operación, comparando su eficiencia con soluciones individuales y distribuidas basadas en convertidores DC/DC convencionales. Los análisis y simulaciones real [...] istas demuestran las ventajas del nuevo convertidor de desvío activo sobre soluciones basadas en convertidores Boost, Buck y Buck-Boost. Abstract in english An active bypass structure is proposed to maximize the power production in photovoltaic modules under mismatched conditions. Its efficiency is compared with single and distributed maximum power point tracking solutions based on conventional DC/DC structures. The analysis and simulations performed un [...] der realistic assumptions demonstrate the benefits of the novel active bypass converter over solutions based on Boost, Buck or Buck-Boost converters.
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.
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...
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.
Transformerless High Step-Up Dc-Dc Converter
Directory of Open Access Journals (Sweden)
Amit S. Surjagade
2014-10-01
Full Text Available This paper proposes a transformer-less high step-up DC-DC converter which acts as an interconnection between DC systems. A new step up converter proposed in the paper is designed and simulated in a simulation environment. The conventional boost converter cannot have any control over the input current at a high duty cycle. Due to which, it draws considerable amount of current from the source which can create problems for the components used in DC-DC converter. Moreover, the voltage stress across the switch comes nearly equal to output voltage. These problems can be overcome in the proposed topology discussed in the paper. The improved topology enhances important electrical parameters such as voltage gain, power loss and switch voltage stress. These improvements in the parameters are explained with the help of formulae explained in the paper. The improved topology improves the voltage stress and voltage gain. The output voltage is modified with the introduction of extra components. Due to improvement in these parameters, the proposed topology becomes an attractive feature for use with DG systems. The comparison is performed between conventional boost converter and boost converter with improved topology. The efficiency curves are plotted for simple boost converter and improved topology. The efficiency is evaluated for a wide range of duty cycle and this confirms the effectiveness of the improved topology discussed in the paper. The proposed converter design and its implementation are given with operational results. The simulation results are tested for an input voltage of 12V. The input voltage is stepped up to output voltage of 100V which can be used for various applications. The interfacing problem of DG system (PV cell arrays with grid will solve using this methodology.
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.
Artificial neural network control of sab dc/dc converter
International Nuclear Information System (INIS)
The latest development of power semiconductor devices enable the modern power electronic converters to withstand high voltage and high power applications. Power electronic converters are mostly periodic variable structure systems due to their switched operations. The main drawback of these converters is the generation of oscillations which are developed during the operation of the converters under nonlinear situations. To handle these nonlinearities, various researchers have proposed different control techniques. Power electronic designers are devoting in the further development of converter topologies and their control techniques. SAB (Single Active Bridge) DC/DC converter is a new topology recently introduced by Demetriades. This topology is used in high voltage and high power applications. Because of its smart features, SAB converter has recently drawn attention of many researchers. However, during the operation of SAB converter severe oscillations are generated. In this research work, a novel NNC (Neural Network Controller) model is developed for SAB converter to minimize oscillations generated during its operation. NNC is believed to be an advanced nonlinear and robust controller which has the ability to map the nonlinear behaviour in a negligible response time. The performance of SAB converter with NNC is tested under dynamic region by considering the reference voltage variation and duty ratio variation. The SAB converter is implemented and simulated in MATLAB/Simulink. The simulated results are presented. (author)
Single-Input Dual-Output (SIDO) Linear-Assisted DC/DC Converter
Martínez García, Herminio; Silva-Martínez, José; Conesa Roca, Alfons; Poveda López, Alberto
2008-01-01
This article describes a single-input dual output (SIDO) linear-assisted DC/DC converter. Linear-assisted DC/DC converters are structures that allow to take advantages of the two classic alternatives in the design of power supply systems: voltage linear regulators and switching DC/DC converters. Thanks to the combination of a switching converter and two voltage linear regulators, the proposed SIDO converter provides two independent outputs with suitable load and line regulations. In the prese...
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.
Very High Frequency Half Bridge DC/DC Converter
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold
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 string and shows an efficiency of 85% at 29 MHz with 130 V input and 13.4 W output. The efficiency was above 82% in the range 110-150 V input with output power between 10.3 W and 16.5 W
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).
Sharda Jaiswal; Debjyoti Chowdhury; Madhurima Chattopadhyay
2014-01-01
Abstract This paper presents a scheme for implementing two different DC/DC converters in the commutation circuitry of BLDC motor drive and corresponding output characteristic in both sensored and sensorless drive. Here we have considered Buck and Boost converters in order to provide a regulated supply to the commutation circuitry. The drive circuit is a closed loop system with a PI controller, Six-Switch Voltage Source Inverter (VSI) and one of the DC/DC converters among Buck and Boost. The p...
A Novel Bidirectional DC-DC Converter With Flyback Snubber For Hybrid Electric Vehicles
DIVYA K.NAIR; ELIZABETH RAJAN
2013-01-01
Hybrid electric Vehicles combine the benefits of engine, electric motor and batteries to provide improved fueleconomy. A converter is needed in hybrid Electric Vehicle for charging and discharging of the batteries. So a charging anddischarging can be combined in one circuit topology known as bidirectional DC-DC converter. Here the output is completelyisolated from input, so an isolated bidirectional Dc-DC converter is used. In the bidirectional DC-DC converter, there occursovervoltage and ove...
High-frequency resonant transistor dc-dc converters
Steigerwald, R. L.
1984-05-01
The design of a transistor dc-dc resonant converter operating at 200-300 kHz is presented, and the operation of a 500-W breadboard version is reported. Several configurations of both voltage-input and current-input type are described and illustrated with circuit diagrams and waveforms, and a full-bridge voltage-input resonant inverter using gate turnoff devices is analyzed in detail, using a piecewise linear approach to obtain design curves. The performance of the breadboard voltage-input half bridge using FET power switches is shown in graphs, demonstrating the low switching losses and transistor stresses achieved by lossless-snubber design. It is predicted that similar designs using bipolar transistors or GTOs can attain energy efficiencies greater than 90 percent. Applications to switching power supplies and battery chargers are suggested.
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.
Design & Implementation of Zero Voltage Switching Buck Converter
A.Suresh Kumar; Krishna Reddy, P.
2014-01-01
Zero voltage switching (ZVS) buck converter is more preferable over hard switched buck converter for low power, high frequency DC-DC conversion applications. In Zero voltage switching converter, turn on & turn off of a switch occurs at zero voltage that results in lower switching losses. In this converter soft switching is achieved by using resonant components. The optimal values of resonant components are determined by using electric functions derived from circuit configurati...
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.)
Load Dump Analysis in a 42/14V DC-DC Converter for Automotive Applications
Directory of Open Access Journals (Sweden)
Mohamed Abdualla Shrud
2013-07-01
Full Text Available The paper presents a model for a dc-dc centralised based architecture using Matlab/Simulink for load dump analysis. As the electrical load varies for various driving conditions such as day or night, summer or winter; and city or country side, the analysis of load change is a very important parameter for system behaviour. In order to study the 42V power generation dynamic performance under load variations, step change in loads have been investigated. A detailed mathematical model for a 3-phase, 4 kW and 42V Lundell alternator average electrical equivalent circuit along with the DC/DC converter based architectures for dual-voltage systems has been covered in previous publications. Aspects of the steady-state output current capabilities, transient behaviour due to load dump on the 14/42V buses and the behaviour of the system model under different loads are assessed and results discussed. The performance of the 42V Lundell alternator with the interleaved six-phase buck dc-to-dc converter system is modelled using Simulink software to assess the effectiveness of the model and its transient behaviour. The simulated results are presented for the transient characteristics of the system for load dumps.
High power density dc/dc converter: Selection of converter topology
Divan, Deepakraj M.
1990-01-01
The work involved in the identification and selection of a suitable converter topology is described. Three new dc/dc converter topologies are proposed: Phase-Shifted Single Active Bridge DC/DC Converter; Single Phase Dual Active Bridges DC/DC Converter; and Three Phase Dual Active Bridges DC/DC Converter (Topology C). The salient features of these topologies are: (1) All are minimal in structure, i.e., each consists of an input and output bridge, input and output filter and a transformer, all components essential for a high power dc/dc conversion process; (2) All devices of both the bridges can operate under near zero-voltage conditions, making possible a reduction of device switching losses and hence, an increase in switching frequency; (3) All circuits operate at a constant frequency, thus simplifying the task of the magnetic and filter elements; (4) Since, the leakage inductance of the transformer is used as the main current transfer element, problems associated with the diode reverse recovery are eliminated. Also, this mode of operation allows easy paralleling of multiple modules for extending the power capacity of the system; (5) All circuits are least sensitive to parasitic impedances, infact the parasitics are efficently utilized; and (6) The soft switching transitions, result in low electromagnetic interference. A detailed analysis of each topology was carried out. Based on the analysis, the various device and component ratings for each topology operating at an optimum point, and under the given specifications, are tabulated and discussed.
A Novel Bidirectional DC-DC Converter With Flyback Snubber For Hybrid Electric Vehicles
Directory of Open Access Journals (Sweden)
DIVYA K.NAIR
2013-06-01
Full Text Available Hybrid electric Vehicles combine the benefits of engine, electric motor and batteries to provide improved fueleconomy. A converter is needed in hybrid Electric Vehicle for charging and discharging of the batteries. So a charging anddischarging can be combined in one circuit topology known as bidirectional DC-DC converter. Here the output is completelyisolated from input, so an isolated bidirectional Dc-DC converter is used. In the bidirectional DC-DC converter, there occursovervoltage and overcurrent stress, which can be reduced by snubber circuits. Various technologies such as RCD, active clampand flyback snubber for bidirectional DC-DC converter are compared. The bidirectional DC-DC converter with flyback snubberis explained in detail. The simulations are carried out using Simulink/MATLAB 7.6.0 (R2009b package. The hardware is doneusing PIC16F877A, a microcontroller to generate the PWM pulses for the MOSFET switches so that harmonics in the circuit canbe reduced.
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...
Energy Technology Data Exchange (ETDEWEB)
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.
Directory of Open Access Journals (Sweden)
Sharda Jaiswal
2014-06-01
Full Text Available Abstract This paper presents a scheme for implementing two different DC/DC converters in the commutation circuitry of BLDC motor drive and corresponding output characteristic in both sensored and sensorless drive. Here we have considered Buck and Boost converters in order to provide a regulated supply to the commutation circuitry. The drive circuit is a closed loop system with a PI controller, Six-Switch Voltage Source Inverter (VSI and one of the DC/DC converters among Buck and Boost. The performances with these two modes of sensored and sensorless have been studied by considering a low speed operation. Finally a comparison has been studied on the basis of characteristics of stator currents, rotor speed and electromagnetic torque. The modeling and simulation of Buck and Boost converter fed BLDC motor is done using MATLAB/SIMULINK for both sensored and sensorless drive.
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...
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
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...
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...
Design and Implementation of a FLC for DC-DC Converter in a Microcontroller for PV System
Directory of Open Access Journals (Sweden)
Abel GarcÃa-B.
2013-07-01
Full Text Available This paper presents the design and implementation of a simple fuzzy logic controller (FLC for a DC-DC buck converter based on the PIC18F4550 microcontroller to control the lead acid battery charging voltage in solar cells applications. For cost consideration, an inexpensive 8-bit microcontroller is selected to program and implement the FLC proportional-integral. The obtained simulation and experimental results show the viability of the controller with a variation on the load of the buck converter showing a good performance on the design of the FLC, and it has also a smooth response with a small overshoot. The DC-DC converter designed in this work can be found applications in low cost photovoltaic (PV systems, although in the literature has been already reported this kind of devices with a better response [3-4], however these use a expensive microcontroller or its designs are very complex, and where these are not necessary for this kind of applications. Finally, a prototype PV system with 100 V/6 A has been implemented for verifying the feasibility of the CD-CD converter.
Magnetic materials and soft-switched topologies for high-current DC-DC converters
Rylko, Marek S.
2011-01-01
The thesis is focused on the magnetic materials comparison and selection for high-power non-isolated dc-dc converters for industrial applications or electric, hybrid and fuel cell vehicles. The application of high-frequency bi-directional soft-switched dc-dc converters is also investigated. The thesis initially outlines the motivation for an energy-efficient transportation system with minimum environmental impact and reduced dependence on exhaustible resources. This is followed by a general o...
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)
An overview of fast DC-DC converters for envelope amplifier in RF transmitters
García Suárez, Oscar; Vasic, Miroslav; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; Cobos Márquez, José Antonio
2012-01-01
In the last years, RF power amplifiers are taking advantage of the switched dc-dc converters to use them in several architectures that may improve the efficiency of the amplifier, keeping a good linearity. The use of linearization techniques such as Envelope Elimination and Restoration (EER) and Envelope Tracking (ET) requires a very fast dc-dc power converter to provide variable voltage supply to the power amplifier but theoretically the efficiency can be much higher than using the classical...
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. Â
Superconducting energy stabilizer with charging and discharging DC-DC converters
International Nuclear Information System (INIS)
This patent describes a superconducting energy stabilizer having multiple load connections and employing DC-DC conversion for storing energy in a superconducting inductive energy storage device having a first end and a second end, and for releasing the stored energy from the superconducting inductive energy storage device to a load or loads or to a utility or an industrial electrical distribution system, the superconducting energy stabilizer having multiple load connections and employing DC-DC conversion. It comprises: energy storage cell means for supplying energy to the load, discharging DC-DC converter means for releasing energy from the superconducting inductive energy storage device to the energy storage cell means, the discharging DC-DC converter means having input terminals, output terminals, and a discharging control line means for carrying signals controlling the operation of the discharging DC-DC converter means, one of the input terminals of the discharging DC-DC converter means coupled to the first end of the superconducting energy storage device
A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
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...
Design of A Bidirectional Dc-Dc Converter For Hybrid Electric Vehicles (HEV Using MATLAB
Directory of Open Access Journals (Sweden)
DHARAM DUTTA, SOUVIK GANGULI
2013-07-01
Full Text Available The design of a 60 kW bidirectional DC-DC converter is addressed in this paper. The paper also discusses the operation and role of dc-dc converter in Electric Vehicle (EV and Hybrid Electric Vehicle (HEV. Various circuits and their analysis are done to review the operation and design of converter. Results show that at 20Hz operation converter efficiency is better when ETD49 shape is used rather than EC70. However efficiencies are greater with ferrite materials rather than iron powder.
Efficiency and Regulation of Commercial Low Power DC/DC Converter Modules at Low Temperatures
Elbuluk, Malik E.; Gerber, Scott; Hammoud, Ahmad; Patterson, Richard L.
2000-01-01
DC/DC converters that are capable of operating at cryogenic temperatures are anticipated to play an important role in the power systems of future NASA deep space missions. Design of these converters to survive cryogenic temperatures will improve the power system performance, and reduce development and launch costs. At the NASA Glenn Research Center Low Temperature Electronics Laboratory, several commercial off-the-shelf dc/dc converter modules were evaluated for their low temperature performance. Various parameters were investigated as a function of temperature, in the range of 20 C to -190 C. Data pertaining to the efficiency and voltage regulation of the tested converters is presented and discussed.
Autonomous ultra-low power DC/DC converter for Microbial Fuel Cells
Adami, Salah-Eddine; Degrenne, Nicolas; Vollaire, Christian; Allard, Bruno; Buret, François; Costa, François
2011-01-01
In this paper, an ultra-low voltage and power DC/DC converter is presented. This converter harvests energy from a Microbial Fuel Cell (MFC) in order to feed another circuit such as an autonomous wireless sensor. The MFC behaves as a voltage generator of 475mV open-circuit voltage with a 600? serial internal impedance. The maximum delivered power is therefore around 100?W. The DC/DC converter provides output voltage in the range 2-7.5V and performs impedance matching with source. The converter...
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.
DC/DC Power Converter for Super-Capacitor Supplied by Electric Power Splitter
Haubert, T.; Mindl, P.
The aim of the article is design of DC/DC converter and discussing of problematic supply using electric power splitter. The electric power splitter with AC/DC converter is source for the DC/DC converter, which is dedicated for charging and discharging of hybrid car drive super-capacitor energy storage. The electric power splitter is synchronous machine with two rotating parts. First rotor contains permanent magnet and the second rotor contains three-phase windings. The amplitude of output voltage depends on difference between first and second rotor speed. The main role of the DC/DC converter is to optimize energy content in super-capacitor storage used to acceleration and deceleration driving period of the passenger car with hybrid electric vehicle (HEV) drive system using electric power splitter.
Elimination of output voltage oscillations in DC-DC converter using PWM with PI controller
Directory of Open Access Journals (Sweden)
Sreenivasappa Veeranna Bhupasandra
2010-01-01
Full Text Available In this paper the SIMULINK model of a PWM controlled DC-DC converter is modeled using switching function concept to control the speed of the DC motor. The presence of the voltage oscillation cycles due to higher switching frequency in the DC-DC converter is identified. The effect of these oscillations on the output voltage of the converter, Armature current, Developed torque and Speed of the DC motor is analyzed. In order to minimize the oscillation cycles the PI controller is proposed in the PWM controller.
Voltage Tracking of a DC-DC Flyback Converter Using Neural Network Control
Wahyu Mulyo Utomo; Sim Sy Yi; Yonis M.Y. Buswig; Afarul Abu Bakar; Md Zarafi Ahmad
2012-01-01
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 starti...
Double Two Switch Forward Soft Switching PWM DC-DC Converter
Hamada, Satoshi; Moisseev, Serguei; Koudriavtsev, Oleg; Nakaoka, Mutsuo
A novel prototype of a double two-switch forward transformer linked zero-voltage and zero-current mode soft-switching (ZVZCS) pulse width modulation (PWM) DC-DC power converter using IGBTs for high power applications is presented. Based on a conventional two-switch forward transformer linked PWM DC-DC converter topology, this converter circuit configuration doesn't include any complex auxiliary resonant circuit. Combining two identical two-switch forward type DC-DC power conversion circuits with a tapped-inductor type DC smoothing filter into a power DC-DC conversion system makes it possible to achieve soft-switching conditions for the active power switches with aid of lossless snubber capacitors and transformer parasitic inductors. Lowered peak voltage across the power switching devices and their related peak current stresses, no transformer saturation effect, reducing of idle and circulating currents through circuit components are practically attained for this converter. This soft-switching PWM DC-DC power converter has some unique advantages such as better power conversion efficiency, lowered output DC ripple current, high power density, constant frequency PWM control scheme, cost effective and wide soft-switching operation range under load variations and PWM regulation settings for high power utilizations. The basic operating principle of the new soft switching power converter treated here is illustrated with approximate periodic steady-state circuit analysis for each mode equivalent circuit. The practical effectiveness of the proposed soft-switching DC-DC power converter is confirmed by the simulation results and is experimentally evaluated on basis of 500W-100kHz breadboard setup using the fast switching IGBTs.
Controlling DC-DC converters by chaos-based pulse width modulation to reduce EMI
International Nuclear Information System (INIS)
In this paper, periodic and chaotic behaviors of DC-DC converters under certain parametric conditions are simulated, experimentally verified, and analyzed. Motivated by the work of J.H.B. Deane and D.C. Hamill in 1996, where chaotic phenomena are useful in suppressing electromagnetic interference (EMI) by adjusting the parameters of the DC-DC converter and making it operate in chaos, a chaos-based pulse width modulation (CPWM) is proposed to distribute the harmonics of the DC-DC converters continuously and evenly over a wide frequency range, thereby reducing the EMI. The output waves and spectral properties of the EMI are simulated and analyzed as the carrier frequency or amplitude changes with regard to different chaotic maps. Simulation and experimental results are given to illustrate the effectiveness of the proposed CPWM, which provides a good example of applying chaos theory in engineering practice.
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
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 ?m up to 1500 ?m (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 efficiency of 97.8%.
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…
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; Andersen, Michael A. E.; Poulsen, Ole; Bjorklund, Thomas
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...
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)
Y-Source Boost DC/DC Converter for Distributed Generation
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede; Andreasen, Søren Juhl; Town, Graham E.
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 presentl...
Trans-inverse (Tx?1) high step-up DC-DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang
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 in the...
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
A new single-switch non-isolated dc-dc converter with very high voltage transfer ratio and reduced semiconductor voltage stress is proposed. The converter utilizes an integrated autotransformer and a coupled inductor on the same core to achieve a very high step-up voltage gain without extreme dut...
Magnetically coupled high-gain Y-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede; Town, Graham
2014-01-01
A new form of magnetically coupled DC/DC converter is proposed for medium power applications (250 W to 2 kW), requiring a high-voltage gain, short inductive charging time and galvanic isolation. The proposed converter can be realised using a unique Y-source impedance network and a two-switch push...
Design of current source DC/DC converter and inverter for 2kW fuel cell application
DEFF Research Database (Denmark)
Andreiciks, A.; Steiks, I.; Krievs, O.; Blaabjerg, Frede
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...
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 between the multiple inputs while the output power is still coupled with all inputs. The energy is accordingly allowed to deliver into the output load simultaneously or at any time-multiplexing scheme. 1-kW experimental prototypes have been built to demonstrate a well-managed power flow for photovoltaic (PV) and battery standalone system.
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...
Symmetrical multilevel converters with two quadrant DC-DC feeding
Schibli, Nikolaus
2000-01-01
In the technology sector of power electronics and control, the multilevel converter technology is still a rather new research area, but the application possibilities in the field of power drives and energy will demand more solutions with this promising technology. In the future, more converter systems will be realized with the multilevel topology. Up to now, multilevel converters have only been used in very particular applications, mainly due to the high costs and complexity of the multilevel...
Isolated Bidirectional DC–DC Converter for SuperCapacitor Applications
Dehnavi, Sayed M. D.; Sen, Gökhan; Thomsen, Ole Cornelius; Andersen, Michael A. E.; Møller, Lars
2011-01-01
This paper proposes a new bidirectional DC/DC converter for supercapacitor applications. The proposed converter has a parallel structure in supercapacitor side (where voltage is low and current is high) and a series structure in the other side. This structure increases efficiency of the converter. For current sharing in the parallel side of the proposed converter, two different methods are recommended and compared in this paper: Current balancing transformer (CBT) and two separate inductors (...
High-current inductors for high-power automotive DC-DC converters
Lyons, Brendan
2008-01-01
This thesis is focused on the investigation of magnetic materials for high-power dcdc converters in hybrid and fuel cell vehicles and the development of an optimized high-power inductor for a multi-phase converter. The thesis introduces the power system architectures for hybrid and fuel cell vehicles. The requirements for power electronic converters are established and the dc-dc converter topologies of interest are introduced. A compact and efficient inductor is critical to reduce the overall...
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,
A Family of Four Quadrant DC/DC Converters with Reduced Number of Components
DEFF Research Database (Denmark)
Mostaan, Ali; Soltani, Mohsen
2015-01-01
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 in proposed converters that can lead to lower cost and also smaller occupied space. The proposed converters are analyzed in detailed and their voltage gain is obtained. It is shown that to obtain high voltage gain, it is not necessary to increase the transformer turn ratio, therefore the leakage inductance effect is minimized in these converters. The effectiveness of the proposed converters is validated with simulation using MATLAB/SIMULINK.
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.
A high voltage gain quasi Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang; Town, Graham
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...
A Comparison of Half Bridge & Full Bridge Isolated DC-DC Converters for Electrolysis Application
Directory of Open Access Journals (Sweden)
R. Samuel Rajesh Babu
2011-09-01
Full Text Available This paper presents a comparison of half bridgeand full bridge isolated, soft-switched, DC-DC converters forElectrolysis application. An electrolyser is a part of renewableenergy system which generates hydrogen from water electrolysisthat used in fuel cells. A DC-DC converter is required to coupleelectrolyser to system DC bus. The proposed DC-DC converter isrealized in both full-bridge and half-bridge topology in order toachieve zero voltage switching for the power switches and toregulate the output voltage. Switching losses are reduced by zerovoltage switching. Switching stresses are reduced by usingresonant inductor and capacitor. The proposed DC-DC converterhas advantages like high power density, low EMI, reducedswitching stresses, high circuit efficiency and stable outputvoltage. The MATLAB simulation results show that the output ofconverter is free from the ripples and regulated output voltage andthis type of converter can be used for electrolyser application .Experimental results are obtained from a MOSFET based DC-DCConverter with LC filter. The
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.
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...
High-voltage boost quasi-Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang; Town, Graham
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...
Fuzzy Logic Controlled DC-DC Converter Based Dynamic Voltage Restorer
Directory of Open Access Journals (Sweden)
Mustafa ?nci
2015-12-01
Full Text Available This paper presents fuzzy logic controlled dc-dc boost converter based Dynamic Voltage Restorer (DVR to compensate severe voltage sag problems in an electrical system. DVR absorbs real power from battery to compensate voltage sags in the system. This condition causes reduction in voltage magnitude of dc-link capacitor. Additionally, DVR requires large dc capacitors to compensate long and severe voltage sags in the system. In this study, dc-dc boost converter is connected to DVR for keeping dc link voltage constant. For this propose, a control algorithm based on Fuzzy Logic (FL control is developed for dc-dc boost converter. The main contribution of this study is that Fuzzy Logic (FL is firstly used to generate reference signal for PWM signals of dc-dc converter applied in DVR. FL is a very flexible controller which keeps the dc link voltage constant during voltage sag. The performance results of proposed study are verified with PSCAD/EMDTC.
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 ......Hz implemented in the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated....
Digital control strategies for DC/DC SEPIC converters towards integration
Li, Nan
2012-01-01
The use of SMPS (Switched mode power supply) in embedded systems is continuously increasing. The technological requirements of these systems include simultaneously a very good voltage regulation and a strong compactness of components. SEPIC ( Single-Ended Primary Inductor Converter) is a DC/DC switching converter which possesses several advantages with regard to the other classical converters. Due to the difficulty in control of its 4th-order and non linear property, it is still not well-expl...
Y-Source Boost DC/DC Converter for Distributed Generation
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede; Andreasen, Søren Juhl; Town, Graham E.
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 unmatched by existing impedance networks. The proposed converter also has more variables for tuning the required gain and, hence, more degrees of freedom for meeting design constraints. These capabilit...
An Experimental Simulation of a Design Three-Port DC-DC Converter
Samir Al Sharif; Ahmad Harb; Haibing Hu; Issa Batarseh
2014-01-01
Traditional DC-DC converter topologies interface two power terminals: a source and a load. The construction of diverse and flexible power management and distribution (PMAD) systems with such topologies is governed by a tight compromise between converter count, efficiency, and control complexity. The broader impact of the current research activity is the development of enhanced power converter systems suitable for a wide range of applications. Potential users of this technology include the des...
Simulation and Implementation of Quasi Resonant DC-DC Converter
N.DEVARAJAN; P. Parvathy
2012-01-01
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 whe...
Comparative Study of PI Controlled and Fuzzy Controlled Buck Converter
Neetu Sharma1 , Dr.Pradyumn Chaturvedi2 , Rahul Dubey
2013-01-01
The main objective of this paper is to compare the performance between fuzzy controller and proportional integral controller in improving the performance of the DC-DC Buck Converter. The evaluation of the output has been carried out and compared by software simulation using MATLAB. This paper also evaluates the stability of the system with fuzzy controller and PI controller and concludes that the fuzzy controller is able to achieve faster transient response, has major stable steady state resp...
A Bidirectional Multi-Port DC-DC Converter Integrating Voltage Equalizer
DEFF Research Database (Denmark)
Chen, Jianfei; Hou, Shiying
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 battery modules with different voltages. Simulation results has shown the feasibility of the proposed converter.
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
interface to the grid. In power electronics, the converter efficiency is characterized at fixed operating voltage for various output power. This type of characterization is not suitable for fuel cells, since as the power from the fuel cell increases, the cell voltage decreases. This paper analyses how the...... fuel cell I-V characteristics influences the power electronics converter efficiency and their consequence on the overall system. A loaddependent efficiency curve is presented based on experimental results from a 6 kW dc-dc converter prototype including the most suitable control strategy which maximizes......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...
A Bidirectional Multi-Port DC-DC Converter Integrating Voltage Equalizer
DEFF Research Database (Denmark)
Chen, Jianfei; Hou, Shiying; Deng, Fujin; Chen, Zhe
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 battery modules with different voltages. Simulation results has shown the feasibility of the proposed converter....
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)
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.
Adaptive Non-singular Terminal Sliding Mode Control for DC-DC Converters
Yu, Y.; Fan, L
2011-01-01
DC-DC converters have some inherent characteristics such as high nonlinearity and time-variation, which often result in some difficulties in designing control schemes. An adaptive non-singular terminal sliding mode control method is presented in this paper. Non-singular terminal sliding mode control is used to make the converter reach steady state within a limited time, and an adaptive law is integrated to the non-singular terminal sliding mode control scheme to make the proposed control me...
LPV model for PV cell and fractional control of DC/DC converter for photovoltaic systems
Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio
2011-01-01
This paper deals with the fractional modelling of a DC-DC converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. A new model for PV cells is proposed in order to obtain a linear equation for V-I characteristic via scheduling dependence of temperature and irradiance. Due to the fractional nature of the ultracapacitors this kind of controller gives a suitable and good performance.
LPV model for PV cells and fractional control of DC/DC converter for photovoltaic systems
Martínez González, Rubén; Bolea Monte, Yolanda; Grau Saldes, Antoni; Martínez García, Herminio
2011-01-01
This paper deals with the fractional modelling of a DC-DC converter, suitable in solar-powered electrical generation systems, and the design of a fractional controller for the aforementioned switching converter. A new model for PV cells is proposed in order to obtain a linear equation for VI characteristic via scheduling dependence of temperature and irradiance. Due to the fractional nature of the ultracapacitors this kind of controller gives a suitable and good performance.
Multistability and Torus Reconstruction in a DC–DC Converter With Multilevel Control
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai T.; Mosekilde, Erik; Pavlova, Elena V.
2013-01-01
By virtue of their limited size and relatively low costs, multilevel dc-dc converters have come to play an important role in modern industrial power supply systems. When operating in a regime of high corrector gain, such converters can display a variety of new dynamic phenomena associated with th...... voltage is increased. The paper also describes the birth of a multilayered resonance torus through a transverse pitchfork bifurcation of the saddle cycle on an ordinary resonance torus....
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.
High Step Up Dc-Dc Converter For Non-Conventional Energy Source
Directory of Open Access Journals (Sweden)
K. Kuralanban
2013-04-01
Full Text Available The demand for non-isolated high step-up dc–dc converters in applications such as dc backup energy systems for UPS, photovoltaicand fuel cell systems, and hybrid electric vehicles has been gradually increasing. This project proposes a non-isolated step-up dc–dc converter with an improved switching method. The proposed converter shows zero-voltage switching turn-on of the switches in continuous conduction mode as well as reduced turnoff switching losses using resonant PWM.As a result of the proposed switching method, the switching losses associated with diode reverse recovery become negligible even in the small duty cycle. The capacitance in the auxiliary circuit is significantly reduced compared to the pulse width modulation method. The duty cycle loss is further reduced resulting in increased step-up ratio.The result of the project is implemented in Simulation using MATLAB Simulink Software.
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)
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 conÃ¯Â¬Ârmed 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 1.5Ãƒâ€” step-up SC converters, the proposed converter can achieve 20%
A DC-DC Converter Efficiency Model for System Level Analysis in Ultra Low Power Applications
Directory of Open Access Journals (Sweden)
Benton H. Calhoun
2013-06-01
Full Text Available This paper presents a model of inductor based DC-DC converters that can be used to study the impact of power management techniques such as dynamic voltage and frequency scaling (DVFS. System level power models of low power systems on chip (SoCs and power management strategies cannot be correctly established without accounting for the associated overhead related to the DC-DC converters that provide regulated power to the system. The proposed model accurately predicts the efficiency of inductor based DC-DC converters with varying topologies and control schemes across a range of output voltage and current loads. It also accounts for the energy and timing overhead associated with the change in the operating condition of the regulator. Since modern SoCs employ power management techniques that vary the voltage and current loads seen by the converter, accurate modeling of the impact on the converter efficiency becomes critical. We use this model to compute the overall cost of two power distribution strategies for a SoC with multiple voltage islands. The proposed model helps us to obtain the energy benefits of a power management technique and can also be used as a basis for comparison between power management techniques or as a tool for design space exploration early in a SoC design cycle.
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; Blaabjerg, Frede
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...
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 VHF Class E DC-DC Converter with Self-Oscillating Gate Driver
Andersen, Toke Meyer; Christensen, Søren K.; Knott, Arnold; Andersen, Michael A. E.
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, is inherently resonant, and switching losses are greatly reduced by ensuring Zero Voltage Switching (ZVS) of the power semiconductor devices. A design method to ensure ZVS operat...
Resonant Boost Dc-Dc Converter for a High Frequency Operation
Tejaswini R,
2013-01-01
With different versions of inverters available, a control of VHF resonant boost dc-dc converter is described in detailed in this paper. Though, a classical Class- ? inverter is well documented in the literature, this is a new version and coupled to resonant rectifier. The twin aspect of any design of resonant boost topology is to mainly feature low device voltage stress and to have high efficiency over wide range of loads. Increased switching frequency allows smaller size of the passive compo...
Dynamic Modelling & Controller Design for Z-Source DC-DC Converter
Directory of Open Access Journals (Sweden)
Shilpa Sarode
2013-04-01
Full Text Available This paper presents the detailed mathematical modeling of Z-source dc-dc converter (ZSC in continuous conduction mode. Transfer function of ZSC is derived based on mathematical modeling with state space averaging method. This paper has been focused on dynamic modeling of open loop transfer function of ZSC along with design of closed loop controller. MATLAB based simulation results are presented for open loop and close loop system of ZSC.
Four Quadrants Integrated Transformers for Dual-input Isolated DC-DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; 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) space orthogonal flux is proposed in this letter. And thus a new geometry core and relative winding arrangements are proposed in accordance with the orthogonal flux decoupling technology. Due to the four s...
Hybrid Wiener-Hammerstein Structure for Grey-Box Modeling of DC-DC Converters
Oliver Ramírez, Jesús Angel; Prieto López, Roberto; Cobos Márquez, José Antonio; García Suárez, Oscar; Alou Cervera, Pedro
2009-01-01
In this work a generic hybrid model for dc-dc converters is proposed. The protections and remote control functions are managed by the logic system (event driven behaviour) and the power stage and control is modelled by a Wiener-Hammerstein structure. The model is oriented to be parameterized based on the information provided by manufacturers in their datasheet and it is able to predict power consumption, efficiency, system stability and large signal behaviour including inrush current, protect...
Solar Photovoltaic Powered Sailing Boat Using Buck Converter
Directory of Open Access Journals (Sweden)
Soumya Das
2015-03-01
Full Text Available The main objective of this paper is to establish technical and economical aspects of the application of stand-alone photovoltaic (PV system in sailing boat using a buck converter in order to enhance the power generation and also to minimize the cost. Performance and control of dc-dc converter, suitable for photovoltaic (PV applications, is presented here. A buck converter is employed here which extracts complete power from the PV source and feeds into the dc load. The power, which is fed into the load, is sufficient to drive a boat . With the help of matlab simulink software PV module and buck model hasÂ beenÂ designed andÂ simulated and also compared with theoretical predictions.
Design and Implementation of Digital Current Mode Controller for DC-DC Converters
DEFF Research Database (Denmark)
Taeed, Fazel
2015-01-01
In the recent decades, shortage of fossil fuels and global warming have increased the demand for renewable energy resources. Dc-dc converters are widely used in renewable energy systems, electric vehicles, and battery chargers. In practical applications, dc-dc converters are required to be regulated by a closed-loop controller. The Peak Current Mode Control (PCMC) is one of the most promising control methods for dc-dc converters. It has been known for high bandwidth (speed), and inherent current protection. Increasing the controller bandwidth decreases the output filter size and cost. Analog controllers (including PCMC) are sensitive to temperature drift, component aging and noise. Digital controllers do not have the aforementioned drawbacks of analog controllers; but they have lower bandwidth than analog controllers due to the sampling and calculation delays. Generally, analog controllers have a bandwidth of 1/10 of the switching frequency. In the current state-of-the-art, the best reported digital PCMC hascrossover frequency of 1/15 of the switching frequency. In this PhD study a novel digital PCMC with negligible delay in the inner current loop has been proposed. The proposed solution has a bandwidth of 1/10 of the switching frequency; which is an improvement of 50% compared to the best reported digital solution, also the achieved crossover frequency is nearly equal to analog controller crossover frequency. Furthermore, the proposed solution offers an adaptive compensation slope; therefore the controlled converter can maintain a high bandwidth over wide range of the operating points. The proposed digital PCMC is modeled and the stability criteria are defined. The digital PCMC is implemented in a Field-Programmable Gate Array (FPGA). The experimental results verify the modeling method and the high predicted bandwidth of the proposed controller. Additionally, the small signal model of the isolated full-bridge boost converter is obtained and the modeling method is verified by experimental results. In modeling, the Equivalent Series Resistance (ESR) of the inductor and capacitor are also included. Analyzing the obtained model reveals that the small values of capacitor and inductor ESR results in a large resonance peak of complex poles in the voltage to duty cycle transfer function. High efficiency dc-dc converters essentially have low ESR in the capacitor and the inductor. Since the complex poles are eliminated in current mode control; applying the current mode control in high efficiency dc-dc converters results in much higher controller bandwidth.
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.
This paper proposes a novel phase-shift plus duty cycle controlled hybrid bi-directional DC-DC converter based on fuel cells and supercapacitors. The described converter employs two high frequency transformers to couple the half-bridge and full-bridge circuits together in the primary side and...... voltage doubler circuit in secondary side. Boost type converter can limit the output ripple current of the fuel cells; hybrid full-bridge structure can change operating modes according to the different input voltage; phase-shift with duty cycle control scheme is utilized to control the bidirectional power...
Y-source impedance-network-based isolated boost DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Town, Graham; Loh, Poh Chiang; Blaabjerg, Frede
A dc-dc converter with very high voltage gain is proposed in this paper for any medium-power application requiring a high voltage boost with galvanic isolation. The proposed converter topology can be realized using only two switches. With this topology a very high voltage boost can be achieved even......-pull transformer for square-wave AC inversion and isolation. The voltage-doubler rectifier provides a constant dc voltage at the output stage. A theoretical analysis of the converter is presented, supported by simulation and experimental results. A 250 W down-scaled prototype was implemented in the laboratory to...
An Efficient High Gain DC-DC Converter for Automotive Applications
Aiswarya T.M.; Prabhakar, M.
2015-01-01
This paper presents a high gain DC-DC converter which uses a clamp circuit to achieve soft switching. The proposed converter is designed to supply a high intensity discharge (HID) lamp used in automobile head lamps. The converter operates from a 12V input supply and provides an output voltage of 120V at 35W output power. A clamp circuit consisting of a clamp capacitor, clamp switch and resonant inductor will help to achieve zero voltage switching (ZVS) of the both main and clamp switches. The...
Design & Implementation of Zero Voltage Switching Buck Converter
Directory of Open Access Journals (Sweden)
A.Suresh Kumar
2014-09-01
Full Text Available Zero voltage switching (ZVS buck converter is more preferable over hard switched buck converter for low power, high frequency DC-DC conversion applications. In Zero voltage switching converter, turn on & turn off of a switch occurs at zero voltage that results in lower switching losses. In this converter soft switching is achieved by using resonant components. The optimal values of resonant components are determined by using electric functions derived from circuit configuration. This type of soft switched resonant converter offers very low electromagnetic interference (EMI.This study presents the circuit configuration with least components to realize highly efficient zero voltage switching resonant converter. It’s feasibility is confirmed with the developed proto type model and experimental results are verified.
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.
An Effective High Step-Up Interleaved DC-DC Converter Photovoltaic Grid Connection System
Directory of Open Access Journals (Sweden)
G. Lakpathi,
2013-09-01
Full Text Available Within the photovoltaic (PV power generation systems in the market, the ac PV module has shown obvious growth. However, a high voltage gain converter is concentrate for the module’s grid connection with dc-ac inverter. This paper proposed a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and numerous turns-ratio of a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the leakage inductor energy of the coupled inductor is efficiently recycled to the load. These features explain about module’s high-efficiency performance. The detailed operating principles and steady-state analyses of continuous mode is described. A 15 volts produces from photovoltaic which is connects to high step-up dc-dc converter to produces output voltage of 170 volts. The novel proposed system is “an effective high step up interleaved dc-dc converter photovoltaic grid connection system”. In this configuration consists of PV array, high step-up interleaved dc-dc converter and three-phase inverter with grid connected system. In this system, the THD value per phase voltage of three phase inverter output without filter is 1.74% with grid connection system. In this same configuration with 2nd order filter connected of three phase inverter output, the THD value reduced to 0.08%. The results are shown in Matlab/simulink 2009a.
Interleaved Self-Oscillating Class E Derived Resonant DC/DC Converters
DEFF Research Database (Denmark)
Kovacevic, Milovan; Knott, Arnold
2012-01-01
A new method for achieving self-oscillating, self-interleaved operation of class E derived resonant DC/DC converters is presented. The proposed method is suitable for operation at frequencies in the Very High Frequency (VHF) band. Interleaved and self-oscillating modes of operation are achieved at the same time with very small number of additional passive components in the interconnection network. To verify the proposed technique, a 110MHz prototype resonant boost converter was designed; experimental results and comparison with SPICE simulation are presented. Peak measured efficiency was 89% in continuous operation.
Transistor Selection and Design of a VHF DC-DC Power Converter
Warren, James R.; Rosowski, Kathryn Anne; Perreault, David J.
2007-01-01
This paper explores the design and performance of dc-dc power converters operating in the very high frequency (VHF, 30-300 MHz) range. Methods are presented for assessment and comparison of device losses in VHF operation under soft switching and soft gating conditions. These methods are applied to the development of a 2 W resonant boost converter operating at a switching frequency of 30 MHz. Design of the power stage, resonant gate drive, and control circuitry are treated in detail, and exper...
Directory of Open Access Journals (Sweden)
Mrs. K.Rajalakshmi#1 , Mr.S.P.Karthick
2013-04-01
Full Text Available This paper describes the design and implementation of high frequency switched full-bridge DC-DC converter using analog control techniques. The major aim of this paper is to provide constant DC voltage to each of the switching equipment of the telephone exchange. In general, all the telephone exchanges are having switching equipment to trace out the route or the communication path to the destination. The voltage to be fed to the switching equipment is obtained from the series connected batteries and is delivered to the DC-DC converter. The DC-DC converter consists of a ferrite transformer. The voltage from the battery is being stepped down by the ferrite transformer according to the requirement. Filters are employed to suppress the harmonics and noise contents in the output voltage. The voltage obtained from the DC-DC converter is controlled by the regulating pulse width modulator using PWM technique.
An Efficient High Gain DC-DC Converter for Automotive Applications
Directory of Open Access Journals (Sweden)
Aiswarya T.M.
2015-06-01
Full Text Available This paper presents a high gain DC-DC converter which uses a clamp circuit to achieve soft switching. The proposed converter is designed to supply a high intensity discharge (HID lamp used in automobile head lamps. The converter operates from a 12V input supply and provides an output voltage of 120V at 35W output power. A clamp circuit consisting of a clamp capacitor, clamp switch and resonant inductor will help to achieve zero voltage switching (ZVS of the both main and clamp switches. The practical performance of the converter was validated through experimental results. Results obtained from the prototype hardware prove that the converter meets the requirements of HID lamp application and can be a very good alternative to existing converters.
Frederick, Martin E.; Jermakian, Joel B.
1994-07-01
A method and an apparatus 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 is introduced. 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 comparing the array voltage with a control voltage from a 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.
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.
Viejo de Frutos, Miriam del; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; García Suárez, Oscar; Cobos Márquez, José Antonio
2010-01-01
High switching frequency allows the integration of low power DC/DC converters. Although a high switching frequency would make feasible a voltage mode control with 1MHz bandwidth, parasitic effects and robustness don’t allow such a high bandwidth. This paper proposes a fast control to optimize the dynamic response of high frequency DC/DC converters. The proposed control is based on the peak current mode control of the output capacitor current. The output capacitor current loop provides...
Comparison of MPPT Algorithms for DC-DC Converters Based PV Systems
Directory of Open Access Journals (Sweden)
A.PRADEEP KUMAR YADAV
2013-01-01
Full Text Available The comparative study between two most popular algorithms technique which is incremental conductance algorithm and perturbs and observe algorithm. Two different converters buck and boost converter use for comparative in this study. Few comparison such as voltage, current and power output for each different combination has been recorded.MATLAB Simulink tools have been used for performance evaluation on energy point.
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
MOS 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...
Digital simulation of closed loop control of bi-directional dc - dc converter
Directory of Open Access Journals (Sweden)
S.A. Elankurisil,
2011-02-01
Full Text Available This paper presents a closed loop control of isolated boost full bridge dc-dc converter for used in Medium and High power application. Zero voltage switching is applied in all switches. The dc inputvoltage is stepped up by using a boost converter. It is inverted using a fullbridge inverter. The transformer is used to produce a higher voltage in secondary voltage side The a.c. voltage is convertedinto d.c. voltage with the help of rectifier. The open loop model there is no possiblity of maintain a constant voltage with variation of input voltage. In closed loop system is maintain a constant voltage is applied with various value of input voltage. Matlab 7.3 version is used for simulating the open loop and closed loop full bridge dc – dc converter are verified. Isolated boost converter can operate at an input voltage of 24V and the output voltage 200-260 V and average efficiency of 89% at 55khz switching frequency.
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)
The PEM Fuel Cell System with DC/DC Boost Converter: Design, Modeling and Simulation
A. Kirubakaran; Jain, Shailendra; R. K. NEMA
2010-01-01
The fuel cells are considered as one of the most promising devices for standalone/grid connected distributed generations (DGs) due to its cleanliness, modularity and higher potential capability. The barriers in the widespread use of fuel cells are their slow response for sudden load changes and higher installation cost. In this paper a simulation study of dynamic behavior of NexaTM 1.2kW PEM fuel cell with DC/DC boost converter is carried out for compact design of PCU. The necessity for the r...
A high power high voltage dc/dc converter for space applications
Weinberg, A.; Schreuders, J.
The design details of a modular dc/dc converter used to power the main anode supply of a mercury ion motor are presented. This motor, the RIT-35 built by M.B.B. Germany, is used as the propulsion unit of a future Asteroid Gravity Optical and Radar Analysis (AGORA) mission. This paper shows the design selected to cope with the high voltage, high power conversion for space applications and the requirement to operate from an unregulated solar array with a voltage excursion of from 150 volts beginning-of-mission (BOM) to 240 volts end-of-mission (EOM).
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)
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...... along with their associated resonance tongues where periodic dynamics is observed. We show how a quintruple-turn torus is transformed into a single-turn torus in a homoclinic bifurcation and examine different mechanisms of torus destruction (via horseshoe formation and through period doubling...
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 VHF Class E DC-DC Converter with Self-Oscillating Gate Driver
DEFF Research Database (Denmark)
Andersen, Toke Meyer; Christensen, SØren K.
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, is inherently resonant, and switching losses are greatly reduced by ensuring Zero Voltage Switching (ZVS) of the power semiconductor devices. A design method to ensure ZVS operation when combining the inverter, rectifier, and gate driver is provided. Several parasitic effects and their influence on converter operation are discussed, and measurement results of a 100 MHz prototype converter are presented and evaluated. The designed prototype converter verifies the described topology.
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.
Control and Analysis of Synchronous Rectifier Buck Converter for ZVS in Light Load Condition
Directory of Open Access Journals (Sweden)
NIMMY JOSEPH
2013-06-01
Full Text Available This paper aims to improve the efficiency of a dc-dc buck converter. It enables a synchronous rectifier buck converter to realize zero voltage switching in light load condition. The replacement of output rectifier diode by MOSFET can minimize conduction losses and increase the efficiency of the circuit. The control technique introduced in this paper enables a SR buck converter to carry out ZVS in light load condition to increase efficiency. No extra auxiliary switches or RLC passive components are required. It is of low cost and easy to control.
Modeling and Simulation of Sensorless Speed Control of a Buck Converter Controlled Dc Motor
Directory of Open Access Journals (Sweden)
Tagreed M. Ali
2010-01-01
Full Text Available This paper investigate a sensorless speed control of a separately excited dc motor fed from a buck type dc-dc converter. The control system is designed in digital technique by using a two dimension look-up table. The performance of the drive system was evaluated by digital simulation using Simulink toolbox of Matlab.
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...
Systematic design approach of fuzzy PID stabilizer for DC-DC converters
International Nuclear Information System (INIS)
DC-DC converters process electrical energy by switching between a fixed number of configurations. The objective of controlling these systems is to provide better performances, ensure closed loop stability and guarantee a simple predictable behaviour. Based on a converter averaged model, we propose, in this paper, a systematic design approach of a fuzzy PID. The choice of controller parameters stands on the whole system stability requirements. Extension of the obtained asymptotic stability to structural stability is presented to show that the developed controller ensures also a simple and predictable behaviour of the converter. Finally, we illustrate the efficiency of the proposed fuzzy PID design approach through simulations in voltage mode as well as in current mode control
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%.
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)
Scientific Electronic Library Online (English)
Fredy Hernán, Martínez Sarmiento; Mariela, Castiblanco Ortíz.
2009-12-01
Full Text Available El control de convertidores DC/DC, topologías utilizadas ampliamente en la reducción activa de contenido armónico para equipo monofásico no lineal de baja potencia, plantea grandes retos de diseño debido a lo complejo del modelo matemático y su característica dinámica altamente no lineal. Técnicas d [...] e inteligencia artificial como las redes neuronales, suponen grandes mejoras en el diseño y desempeño final, dada su capacidad de aprender dinámicas complejas y generalizar su comportamiento. La motivación de este trabajo fue la de plantear (y posteriormente evaluar la respuesta dinámica) un lazo de control directo con redes neuronales, que permitiera adicionalmente eliminar elementos de prueba y error en su diseño. Se propone un control directo basado en red neuronal artificial, cuyo diseño se realizó de forma óptima utilizando modelos de búsqueda bioinspirada, esto para optimizar simultáneamente dos aspectos diferentes pero fundamentales de la red: la arquitectura y los pesos de las conexiones. El control es aplicado a un convertidor boost. Los resultados obtenidos permiten observar el desempeño dinámico del esquema, para el cual los tiempos de respuesta y los delta de voltaje en la salida permiten concluir que los criterios seleccionados para el diseño del control son apropiados y representan un aporte en el desarrollo de aplicaciones de control de sistemas conmutados DC/DC. Abstract in english Controlling DC/DC converters (topologies widely used in the active reduction of harmonic content for singlephase nonlinear low power equipment) raises great design challenges due to the mathematical model's complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniqu [...] es, such as neuronal networks, suppose great improvements in design and final performance, given their capacity for learning complex dynamics and generalising their behaviour. This work was aimed at proposing (and evaluating dynamic response later on) direct control link with neuronal networks which also allowed eliminating test elements and error in its design. Artificial neuronal networkbased direct control was designed as well as possible using bioinspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme's dynamic performance; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of DC/DC switchmode systems.
Directory of Open Access Journals (Sweden)
Sergio Serna
2012-11-01
Full Text Available A novel asymmetrical interleaved dc/dc switching converters family intended for photovoltaic and fuel cell applications is presented in this paper. The main requirements on such applications are small ripples in the generator and load, as well as high voltage conversion ratio. Therefore, interleaved structures and voltage multiplier cells have been asymmetrically combined to generate new converters, which inherently operate indiscontinuous conduction mode. The novel family is derived from boost, buck-boost and flyback-based structures. This converter family is analyzed to obtain the design equations and synthesize a design process based on the typical requirements of photovoltaic and fuel cell applications. Finally, the experimental results validate the characteristics and usefulness of the asymmetrical interleaved converter family.
Chien-Wei Ma; Jaw-Kuen Shiau
2013-01-01
This paper analyzes and simulates the Li-ion battery charging process for a solar powered battery management system. The battery is charged using a non-inverting synchronous buck-boost DC/DC power converter. The system operates in buck, buck-boost, or boost mode, according to the supply voltage conditions from the solar panels. Rapid changes in atmospheric conditions or sunlight incident angle cause supply voltage variations. This study develops an electrochemical-based equivalent circuit mod...
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.
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.
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.
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
investigated individually. The tradeoffs among these factors have to be analyzed in order to achieve optimal parameters. Combined with a certain application, four typical winding arrangements have been compared to illustrate each their advantages and disadvantages. An improved interleaving structure with......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....
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.
A dual VCDL DLL based gate driver for zero-voltage-switching DC-DC converter
International Nuclear Information System (INIS)
This paper presents a dual voltage-controlled-delay-line (VCDL) delay-lock-loop (DLL) based gate driver for a zero-voltage-switching (ZVS) DC-DC converter. Using the delay difference of two VCDLs for the dead time control, the dual VCDL DLL is able to implement ZVS control with high accuracy while keeping good linearity performance of the DLL and low power consumption. The design is implemented in the CSM 2P4M 0.35 ?m CMOS process. The measurement results indicate that an efficiency improvement of 2%-4% is achieved over the load current range from 100 to 600 mA at 4 MHz switching frequency with 3.3 V input and 1.3 V output voltage.
Resonant Boost Dc-Dc Converter for a High Frequency Operation
Directory of Open Access Journals (Sweden)
Tejaswini R,
2013-07-01
Full Text Available With different versions of inverters available, a control of VHF resonant boost dc-dc converter is described in detailed in this paper. Though, a classical Class- ? inverter is well documented in the literature, this is a new version and coupled to resonant rectifier. The twin aspect of any design of resonant boost topology is to mainly feature low device voltage stress and to have high efficiency over wide range of loads. Increased switching frequency allows smaller size of the passive components, allowing one to use air-core magnetic, and thereby reducing core loss. The output is regulated by MPPT controller. The performance analysis was carried out on MATLAB/Simulink platform and performance characteristics are presented along with the values of components.
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 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.
Design Of Vswt With Lcl Resonant Dc-dc Converters For Rl Load
M. Vijaya Kumar; M. Annamalai
2012-01-01
This paper deals with design of variable speed wind turbine (VSWT) with LCL resonantDC-to-DC converter for stand-alone wind energy system with RL load. The wind turbinesystem consists of synchronous generator (SG), full bridge diode rectifier, buck DC- DCconverter and inverter with RL load is present. Based on this electrical model, a Simulinkmodel of the system are simulated by using MATLAB Simulink power system blocks. Thisconverter has advantages like reduced transformer size, reduced filt...
High Step up DC-DC Converter with PID Controller for Photovoltaic Applications
Directory of Open Access Journals (Sweden)
Rakesh Kumar Goudanaikar
2014-06-01
Full Text Available From the literature survey, it is observed that the need of ac photovoltaic modules in photovoltaic (PV power-generation market has increased. However, the important aspect is a requirement of a high voltage gain converter for the module’s grid connection through a dc–ac inverter. A high step up dc-dc converter using PI controller is proposed and presented in this paper. Further, the converter proposed in this paper employs a floating active switch, which is designed to isolate the dc current from the PV panel when the ac module is off-grid as well as in the non-operating condition. This isolation will ensure the operation of the internal components without any residential energy being transferred to the output or input terminal,. The PI controller is used in feedback in order to speed-up the response. The converter achieves a high step-up voltage-conversion ratio without extreme duty ratio and the numerous turns-ratios of a coupled inductor. The leakage inductor energy of the coupled inductor is efficiently recycled to the load. The proposed converter model along with PI controller is modeled using SIMULINK and the simulation results are presented in this paper to authenticate the proposed scheme.
Analysis of a Multi-Oscillated Current Resonant Type DC-DC Converter
Matsuo, Osamu; Matsuo, Hirofumi; Ishizuka, Yoichi; Ota, Hiroyuki
This paper presents the analysis of a new multi-oscillated current resonant type DC-DC converter. Current resonant converters have several remarkable features such as high efficiency, small size, low cost and low noise, and are frequently employed in many portable electronic systems such as personal computers, cellular phones and flat panel displays. The current resonant type converter generally employs pulse frequency modulation for constant voltage control in the output. For this reason, the magnetizing current through the converter not only causes a power loss under a light load, but also a loss during stand-by. Therefore, this type of converter has a problem in that the required smaller size cannot be achieved, because an auxiliary source is necessary for stand-by. In order to solve these problems, a new current resonant type power supply is proposed in which two driving methods are employed. In these driving methods, one MOSFET as a main switch is driven by an auxiliary winding of the transformer and another MOSFET as a main switch is driven by the driving IC with a low withstand voltage. Good agreement of the observed and simulated waveforms was confirmed. In addition, eight distinct states and four distinct operating modes, which compose of the sequence of states, were clarified by experimental and simulated analysis.
Directory of Open Access Journals (Sweden)
Sugandhra Pal Singh
2014-07-01
Full Text Available In this paper, we study on buck dc/dc converter of high efficiency by soft switching technique. The paper will focus on modeling, analysis, and design and simulation buck converter architecture. The converter is designed in CCM (continuous conduction mode. The voltage mode control strategy is proposed by using pulse width modulation (PWM with a proportional-integral (PI. The effectiveness of the step down converter is verified through simulation results using control oriented simulator like MATLAB/Simulink tools. The circuit operation, designs and simulation results are mentioned in this paper.
Analysis of Dc/Dc converters with PWM and sliding mode controls
International Nuclear Information System (INIS)
Static and dynamic performances of D C/D C converters with PWM and sliding mode controllers are investigated. To improve the performance of the PWM controller, a linear compensator is proposed and used. For sliding controller, important parameters such as sliding coefficients and filter time constant are carefully computed and used. Finally, a D C/D C buck converter with PWM and sliding controller is designed, modeled and constructed. Theoretical and experimental results are compared and the distinguished features and limitations of each control technique are presented
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
DEFF Research Database (Denmark)
Mira Albert, Maria del Carmen; Zhang, Zhe; Knott, Arnold; Andersen, Michael A. E.
DC microgrids or nanogrids have attracted increasing research interest in recent years. Therefore, as a critical component, dc-dc converters with multiple inputs are required. In this paper, a dual-input interleaved buck/boost converter is proposed and its corresponding power flow control methods...
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 and the...... voltage transfer gain is obtained. It is also demonstrated that the voltage stress on all semiconductor devices is restricted to input voltage which allows the utilization of a power switch with lower drain source resistance. In order to further increase the voltage gain another switched capacitor voltage...... multiplier cell can be added to the proposed converter. By using the state space average technique it is shown that the control to output transfer function of the proposed converter and its derivatives doesn't have right half plane zero (R.H.P.Z) that makes the dynamic behavior of these converters very fast...
High-voltage boost quasi-Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede
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 converter uses less switches, a smaller common duty cycle and less turns for the transformer when compared with existing topologies. Its size and weight are therefore smaller, whereas its efficiency is higher. It is therefore well-suited for applications, where a wide range of voltage gain is required like renewable energy systems, DC power supplies found in telecom, aerospace and electric vehicles. To demonstrate the performance of the proposed converter, a 400 V, 500 W prototype has been implemented in the laboratory. Efficiency of the prototype measured is found to vary from 89.0 to 97.4% when its input voltage changes from 44 to 82 V at full load.
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.
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 â€œelectrolytic capacitor protection circuitâ€, 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.
PV and Wind Energy Hybrid Integrated Full-Bridge-DC–DC Converter for a Residential Application
Directory of Open Access Journals (Sweden)
G.Revan Sidda
2014-09-01
Full Text Available Hybrid power system can be used to reduce energy storage requirements. There is increasing demand for the use of alternate or renewable energy sources to achieve clean and low-cost electricity for Residential Application The PV-wind hybrid system returns the lowest unit cost values to maintain the same level of DPSP as compared to standalone solar and wind systems. For all load demands the levelised energy cost for PV-wind hybrid system is always lower than that of standalone solar PV or wind system. The PV-wind hybrid option is techno-economically viable for rural electrification. This paper proposes a novel integrated converter topology for interfacing between the energy storage system and the dc bus for a residential microgrid application The proposed integrated full-bridge dc–dc converter presents the following features: low number of active devices compared to the converters usually applied to similar applications, low input and output current ripple, high voltage ratio, bidirectional power flow, and galvanic isolation.
Basic circuits to design switched-based DC-DC converters
Directory of Open Access Journals (Sweden)
F Sandoval-Ibarra
2007-12-01
Full Text Available The purpose of this paper is twofold. On one hand, basics on switched circuits for designing a DC-DC converter are presented and, on the other hand, power electronics definitions associated with simple electrical networks are mentioned. In the analysis of these networks, it is necessary to take into account not only converters' non-idealities but also how to minimize power losses. Since power losses may be minimized by increasing the clock frequency of switched-based converters, experimental results of basic clock generators are presented. These generators were implemented with low-cost componentsEl propósito de este artículo es doble. Por un lado, se presentan conceptos básicos de circuitos conmutados para diseñar un convertidor CD-CD y, por el otro, se rescatan definiciones de electrónica de potencia asociadas a redes eléctricas simples. En el análisis de esas redes es necesario tomar en cuenta no solo las no idealidades de los convertidores sino también cómo minimizar pérdidas de potencia. Porque las perdidas de potencia pueden ser minimizadas aumentando la frecuencia de reloj de los convertidores conmutados, se presentan resultados experimentales de generadores de reloj. Estos circuitos fueron implementados con componentes de bajo costo
Basic circuits to design switched-based DC-DC converters
Scientific Electronic Library Online (English)
F, Sandoval-Ibarra; J.R, Mercado-Moreno; L.H, Urióstegui-Vázquez.
2007-12-01
Full Text Available El propósito de este artículo es doble. Por un lado, se presentan conceptos básicos de circuitos conmutados para diseñar un convertidor CD-CD y, por el otro, se rescatan definiciones de electrónica de potencia asociadas a redes eléctricas simples. En el análisis de esas redes es necesario tomar en c [...] uenta no solo las no idealidades de los convertidores sino también cómo minimizar pérdidas de potencia. Porque las perdidas de potencia pueden ser minimizadas aumentando la frecuencia de reloj de los convertidores conmutados, se presentan resultados experimentales de generadores de reloj. Estos circuitos fueron implementados con componentes de bajo costo Abstract in english The purpose of this paper is twofold. On one hand, basics on switched circuits for designing a DC-DC converter are presented and, on the other hand, power electronics definitions associated with simple electrical networks are mentioned. In the analysis of these networks, it is necessary to take into [...] account not only converters' non-idealities but also how to minimize power losses. Since power losses may be minimized by increasing the clock frequency of switched-based converters, experimental results of basic clock generators are presented. These generators were implemented with low-cost components
An imroved design for ZVT DC-DC PWM converters with snubber assisted auxiliary switch
Scientific Electronic Library Online (English)
J., Russi; M. L., Martins; H. A., Gründling; H., Pinheiro; J. R., Pinheiro; H. L., Hey.
2005-03-01
Full Text Available Este artigo propõe uma metodologia de projeto aprimorada para determinação dos componentes auxiliares para o conversor ZVT CC-CC PWM snubber assisted auxiliary switch. O procedimento de projeto proposto é baseado na redução das perdas de condução no circuito auxiliar. Isto é somente possível devido [...] à localização do capacitor snubber de bloqueio, o qual é compartilhado por ambas as chaves ativas. Através do procedimento de projeto proposto o rendimento do conversor pode ser aumentado. Uma análise comparativa do rendimento é apresentada e os resultados experimentais, obtidos de protótipos de laboratório de 1 kW, 100 kHz, mostram uma melhoria relevante em relação ao rendimento apresentado pelo projeto original. Além disso, os resultados experimentais também confirmam que o projeto proposto para o conversor ZVT snubber assisted auxiliary switch torna-o competitivo em relação ao conversor ZVT PWM com fonte auxiliar de tensão constante (true PWM ZVS pole). Abstract in english This paper proposes an improved design to calculate the snubber auxiliary elements of ZVT DC-DC PWM converters with snubber assisted auxiliary switch. The proposed improved design guidelines are based on the reduction of the conduction losses through the auxiliary circuit. It is accomplished by the [...] unique location of the turn-off snubber capacitor, which is shared by both active switches. By means of this improved design guidelines the converter efficiency can be increased. An efficiency comparative analysis is carried out and the experimental results, obtained from 1 kW, 100 kHz laboratory prototypes, show a relevant improvement in converter efficiency compared to the original converter design. In addition, experimental results also confirm that with the improved design the ZVT PWM converters with snubber assisted auxiliary switch can be competitive with ZVT PWM converters with constant auxiliary voltage source (True PWM ZVS pole).
Garcerá Sanfeliú, Gabriel; González Medina, Raul; Figueres Amorós, Emilio; Sandia Paredes, Jesús
2012-01-01
In photovoltaic (PV) double-stage grid-connected inverters a high-frequency DC-DC isolation and voltage step-up stage is commonly used between the panel and the grid-connected inverter. This paper is focused on the modeling and control design of DC-DC converters with Peak Current mode Control (PCC) and an external control loop of the PV panel voltage, which works following a voltage reference provided by a maximum power point tracking (MPPT) algorithm. In the proposed overall control structur...
DEFF Research Database (Denmark)
Sanjeevikumar, Padmanaban; Grandi, Gabriele; Wheeler, Patrick; Blaabjerg, Frede; Loncarski, J.
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...
Fast response double series resonant high-voltage DC-DC converter
International Nuclear Information System (INIS)
In this paper, a novel double series resonant high-voltage dc-dc converter with dual-mode pulse frequency modulation (PFM) control scheme is proposed. The proposed topology consists of two series resonant tanks and hence two resonant currents flow in each switching period. Moreover, it consists of two high-voltage transformer with the leakage inductances are absorbed as resonant inductor in the series resonant tanks. The secondary output of both transformers are rectified and mixed before supplying to load. In the resonant mode operation, the series resonant tanks are energized alternately by controlling two Insulated Gate Bipolar Transistor (IGBT) switches with pulse frequency modulation (PFM). This topology operates in discontinuous conduction mode (DCM) with all IGBT switches operating in zero current switching (ZCS) condition and hence no switching loss occurs. To achieve fast rise in output voltage, a dual-mode PFM control during start-up of the converter is proposed. In this operation, the inverter is started at a high switching frequency and as the output voltage reaches 90% of the target value, the switching frequency is reduced to a value which corresponds to the target output voltage. This can effectively reduce the rise time of the output voltage and prevent overshoot. Experimental results collected from a 100-W laboratory prototype are presented to verify the effectiveness of the proposed system.
High Current Planar Transformer for Very High Efficiency Isolated Boost DC-DC Converters
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe
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 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 in an optimal way.
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.
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 ?m process which provided a 12 volt input and were still radiation hard. These results are reported here and in previous papers. Plug in power cards with ×10 voltage ratio are being developed for testing the hybrids with ABCN chips. These plug-in cards have air coils but use commercial chips that are not designed to be radiatio...
Optimal Design and Tradeoff Analysis of Planar Transformer in High-Power DC–DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Thomsen, Ole Cornelius
2012-01-01
The trend toward high power density, high operating frequency, and low profile in power converters has exposed a number of limitations in the use of conventional wire-wound magnetic component structures. A planar magnetic is a low-profile transformer or inductor utilizing planar windings, instead of the traditional windings made of Cu wires. In this paper, the most important factors for planar transformer (PT) design including winding loss, core loss, leakage inductance, and stray capacitance have individually been investigated. The tradeoffs among these factors have to be analyzed in order to achieve optimal parameters. Combined with an application, four typical winding arrangements have been compared to illustrate their advantages and disadvantages. An improved interleaving structure with optimal behaviors is proposed, which constructs the top layer paralleling with the bottom layer and then in series with the other turns of the primary, so that a lower magnetomotive force ratio $m$ can be obtained, as wellas minimized ac resistance, leakage inductance, and even stray capacitance. A 1.2-kW full-bridge dc–dc converter prototype employing the improved PT structure has been constructed, over 96% efficiency is achieved, and a 2.7% improvement, compared with the noninterleaving structure, is obtained.
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.)
Design and Simulation of a soft switching scheme for a dc-dc Boost Converter with pi controller
Directory of Open Access Journals (Sweden)
X.Felix Joseph
2010-10-01
Full Text Available This paper presents the design of simple but powerful soft switching scheme for a DC-DC Boost Converter with a closed loop control. A new novel soft switching scheme is proposed with a single switch and minimum components which offers load independent operations. The only switch used in this converter is switched ON at zero current and switched OFF at zero voltage .The proposed Controller is used to improve the dynamic performance of DC-DC converter by achieving a robust output voltage against load disturbances. The duty cycle of the Boost converter is controlled by PI Controller. A 50W/50KHz soft switched PWM Boost converter is simulated and analyzed. The results are simulated using PSIM
Dynamic analysis of the input-controlled buck converter fed by a photovoltaic array
Directory of Open Access Journals (Sweden)
Marcelo Gradella Villalva
2008-12-01
Full Text Available The control of the input voltage of DC-DC converters is frequently required in photovoltaic applications. In this special situation, unlike conventional converters, the output voltage is constant and the input voltage is controlled. This paper deals with the analysis and the control of the buck converter with constant output voltage and variable input.O controle da tensão de entrada de conversores DC-DC é freqüentemente necessário em aplicações com energia fotovoltaica. Nesta situação especial, diferentemente do que ocorre com conversores convencionais, a tensão de saída é constante e a tensão de entrada é variável. Este artigo versa sobre a análise e o controle do conversor buck com tensão de saída constante e tensão de entrada variável.
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...
National Aeronautics and Space Administration â€” 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...
Zumel, P.; Fernandez, C.; Sanz, M.; Lazaro, A.; Barrado, A.
2011-01-01
In this paper, a short introductory course to introduce field-programmable gate array (FPGA)-based digital control of dc/dc switching power converters is presented. Digital control based on specific hardware has been at the leading edge of low-medium power dc/dc switching converters in recent years. Besides industry's interest in this topic, from…
Developments on DC/DC converters for the LHC experiment upgrades
International Nuclear Information System (INIS)
Prototypes of DC/DC power and Point of Load (PoL) converters were designed and built with the aim of satisfying the foreseen working parameters of the High Luminosity (HL) LHC experiments, using both Silicon (Si) MOSFETs and/or more recent devices substantiated of better power performance, like Silicon Carbide (SiC) and Gallium Nitride (GaN) transistors. Optimization of their design, based on the comparison between the simulated and measured thermal, electrical and mechanical performance, is in progress, and many improvements with respect to the previous versions are under implementation. We discuss in this paper the results of the last modifications. In addition, many tens of discrete component samples, chosen among the devices commercially available in the three different technologies (Si, SiC and GaN), were electrically characterized and tested under ?-rays, neutron, proton and heavy ion radiation, also using a combined run method. We have also planned to test some commercial DC/DCs under the extreme conditions of radiation and magnetic field expected in the upgrades of the LHC experiments. Here we show the first results on few samples
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; Blaabjerg, Frede
2013-01-01
Silicon carbide (SiC) and other wide band gap devices are in these years undergoing a rapid development. The need for higher efficiency and smaller dimensions are forcing engineers to take these new devices in to considerations when choosing semiconductors for their converters. In this article a Si 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. ...
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.
An imroved design for ZVT DC-DC PWM converters with snubber assisted auxiliary switch
Directory of Open Access Journals (Sweden)
J. Russi
2005-03-01
Full Text Available This paper proposes an improved design to calculate the snubber auxiliary elements of ZVT DC-DC PWM converters with snubber assisted auxiliary switch. The proposed improved design guidelines are based on the reduction of the conduction losses through the auxiliary circuit. It is accomplished by the unique location of the turn-off snubber capacitor, which is shared by both active switches. By means of this improved design guidelines the converter efficiency can be increased. An efficiency comparative analysis is carried out and the experimental results, obtained from 1 kW, 100 kHz laboratory prototypes, show a relevant improvement in converter efficiency compared to the original converter design. In addition, experimental results also confirm that with the improved design the ZVT PWM converters with snubber assisted auxiliary switch can be competitive with ZVT PWM converters with constant auxiliary voltage source (True PWM ZVS pole.Este artigo propÃµe uma metodologia de projeto aprimorada para determinaÃ§Ã£o dos componentes auxiliares para o conversor ZVT CC-CC PWM snubber assisted auxiliary switch. O procedimento de projeto proposto Ã© baseado na reduÃ§Ã£o das perdas de conduÃ§Ã£o no circuito auxiliar. Isto Ã© somente possÃvel devido Ã localizaÃ§Ã£o do capacitor snubber de bloqueio, o qual Ã© compartilhado por ambas as chaves ativas. AtravÃ©s do procedimento de projeto proposto o rendimento do conversor pode ser aumentado. Uma anÃ¡lise comparativa do rendimento Ã© apresentada e os resultados experimentais, obtidos de protÃ³tipos de laboratÃ³rio de 1 kW, 100 kHz, mostram uma melhoria relevante em relaÃ§Ã£o ao rendimento apresentado pelo projeto original. AlÃ©m disso, os resultados experimentais tambÃ©m confirmam que o projeto proposto para o conversor ZVT snubber assisted auxiliary switch torna-o competitivo em relaÃ§Ã£o ao conversor ZVT PWM com fonte auxiliar de tensÃ£o constante (true PWM ZVS pole.
Dynamic analysis of the input-controlled buck converter fed by a photovoltaic array
Scientific Electronic Library Online (English)
Marcelo Gradella, Villalva; Ernesto, Ruppert Filho.
2008-12-01
Full Text Available O controle da tensão de entrada de conversores DC-DC é freqüentemente necessário em aplicações com energia fotovoltaica. Nesta situação especial, diferentemente do que ocorre com conversores convencionais, a tensão de saída é constante e a tensão de entrada é variável. Este artigo versa sobre a anál [...] ise e o controle do conversor buck com tensão de saída constante e tensão de entrada variável. Abstract in english The control of the input voltage of DC-DC converters is frequently required in photovoltaic applications. In this special situation, unlike conventional converters, the output voltage is constant and the input voltage is controlled. This paper deals with the analysis and the control of the buck conv [...] erter with constant output voltage and variable input.
Bifurcation and Chaos in a Pulse Width modulation controlled Buck Converter
DEFF Research Database (Denmark)
Kocewiak, Lukasz; Bak, Claus Leth; Munk-Nielsen, Stig
2007-01-01
Power electronic system with pulse width modulation (PWM) control is studied. Behaviour characteristic for a nonlinear dynamical system is observed and theoretically explained. A DC-DC buck converter controlled by a voltage feedback is taken as an example. The studied system is described by a system of piecewise-smooth nonautonomous differential equations. The research are focused on chaotic oscillations analysis and analytical search for bifurcations dependent on parameter. The most frequent ro...
MartÃnez GarcÃa, Herminio
2015-01-01
This article shows the proposal of a linearâ€“assisted converter or linearâ€“&â€“switching hybrid converter with a constant switching frequency for photovoltaic solar DC-DC regulators. The control loop of the system is based on the currentâ€“mode technique. The main disadvantage of a converter with currentâ€“mode control is the inherent instability of the loop when switch duty ratios are greater than 0.5. In order to make stable the proposed linearâ€“assisted converter, the article shows the technique ba...
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.
Design and Robustness Analysis of a PID Based Sliding Mode Controller for a dc-dc Converter
D.M.Mary Synthia Regis Prabha; S.Pushpa Kumar; G.Glan Devadhas
2012-01-01
This study deals with the design and analysis of a dc-dc converter operating in continuous conduction mode with Proportional-Integral-Derivative control and PID based Sliding Mode Control (SMC). A small signal model is developed using Switching Flow Graph (SFG) from which the control coefficients for the PID controller is selected. PID based SMC uses a control law which constrains the weighted sum of the voltage error, its derivatives and the integral of the voltage error to zero. The equival...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.; Rahimullah, Sarban
2013-01-01
This paper presents driving circuit for a recently invented dielectric electro active polymer (DEAP) incremental actuator. The basic operation of such an actuator is bioinspired from the movement of an inchworm. The actuator consists of three electrically isolated, and mechanically connected capacitive sub-actuators. It needs to be driven by three high voltage (~2.5 kV) DC-DC converters, to achieve the linear incremental motion. The topology used for this application is a bi-directional flyback ...
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...
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) space orthogonal flux is proposed in this paper. And thus a new geometry core and relative winding arrangements are proposed in accordance with the rthogonal flux decoupling technology. Due to the four sec...
García Suárez, Oscar; Vasic, Miroslav; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; Díaz López, Daniel; Cheng, Pengming; Cobos Márquez, José Antonio
2011-01-01
Classical linear amplifiers such as A, AB and B offer very good linearity suitable for RF power amplifiers. However, its inherent low efficiency limits its use especially in base-stations that manage tens or hundreds of Watts. The use of linearization techniques such as Envelope Elimination and Restoration (EER) allow an increase of efficiency keeping good linearity. This technique requires a very fast dc-dc power converter to provide variable voltage supply to the power amplifier. In this pa...
Implementation of Buck-Boost Converter with Coupled Inductor for Photo-Voltaic System
Directory of Open Access Journals (Sweden)
M.S. Subbulakshmi
2014-12-01
Full Text Available The solar energy is a very interesting alternative on supplement the electrical system generation. In this paper, a photovoltaic based system is obtained from a boost cascaded with a buck converter along with Coupled inductor. Due to its novel operating modes, high efficiency can be achieved because there is only one switch operating at high frequency at a time, and the converter allows the use of power MOSFET and ultra-fast reverse recovery diode. This paper begins with theoretical analysis and modeling of this boost–buck converter. The model indicates that the coupled inductance will lead to an increase in the gain and the decrease in ripples. Finally, this paper analyzes and describes step by step the process of designing, and simulation of high efficiency low ripple voltage buck boost DC-DC converter for the photovoltaic solar conversion system
Non-Inverting Buck-Boost Converter for Fuel Cell Applications
DEFF Research Database (Denmark)
Schaltz, Erik; Rasmussen, Peter Omand; Khaligh, Alireza
this paper the non-inverting buck-boost with either diodes or synchronous rectifiers is investigated for fuel cell applications. Most of previous research does not considerÂ the parasitic in the evaluation of the converters. In this study, detailed analytical expressions of the efficiencies for the......Fuel cell DC/DC converters often have to be able to both step-up and step-down the input voltage, and provide a high efficiency in the whole range of output power. ConventionalÂ negative output buck-boost and non-inverting buck-boost converters provide both step-up and step-down characteristics. In...... system composed of fuel cell system and interfacing converter, considering the parasitics, are presented. It is concluded that the implementation with synchronous rectifiers provides the highest efficiency in the whole range of the fuel cell power, and its efficiency characteristic is more suitable for...
Boumediène Allaoua; Brahim Mebarki; Abdellah Laoufi
2013-01-01
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 ...
Directory of Open Access Journals (Sweden)
Ching-Ming Lai
2015-09-01
Full Text Available The objective of this paper is to implement a two-phase, interleaved, bidirectional DC/DC converter topology with an improved voltage conversion ratio for electric vehicle (EV and DC-microgrid systems. In this study, a two-phase interleaved charge-pump topology is introduced to achieve a high voltage conversion ratio with very simple control circuits. In discharge mode, the circuit topology acts as a voltage-multiplier boost converter to achieve a high step-up conversion ratio (48 V to 240 V. In charge mode, the circuit topology acts as a voltage-divider buck converter to achieve a high voltage step-down conversion ratio (240 V to 48 V. The circuit configuration, operating principle, steady-state analysis and the closed-loop control of the proposed converter are presented. Experiments conducted on a laboratory prototype with 500 W power-rating are presented to verify the effectiveness. The maximum efficiency levels in discharge and charge modes are about 97.7% and 98.4% respectively.
DC-DC CONVERTER WITH VOLTAGE CONTROLLER FOR STAND ALONE WIND ENERGY SYSTEM
Directory of Open Access Journals (Sweden)
A. Bala Chandana
2015-05-01
Full Text Available This paper deals with the design and simulation of DC-DC voltage regulator using closed loop system with pulse width modulation technique and are simulated using MATLAB/SIMULINK power system blocks. This system has advantages like current source characteristics, reduced filter size and reduced transformer size. The simulink circuit model for open loop controller and closed loop model with PI controller are developed, compared and used for simulation studies. Results of the simulation are presented.
A Cascaded Quasi Z-Source Scheme Step up DC-DC Converter Using ANN Based Control.
R.Praburaja; Karthikeyan, C.
2013-01-01
Modern renewable generation systems need smart and integrated power converters ensure for high efficiency of power conversion .This project intends to the Artificial Neural Network (ANN) based control step up DC-DC converter family with a cascaded Quasi Z-source network (qZS-scheme).The cascaded (two-stage) qZS- network could be derived by the adding of one diode, one inductor, and two capacitors to the traditional single stage quasi-Z-source inverter (qZSI). The proposed cascaded qZSI giving...
Directory of Open Access Journals (Sweden)
T.Umaranjani
2012-05-01
Full Text Available This paper deals with reducing switching loss, reducing voltage and current stresses, and reducing conduction loss due to circulation current. An isolated bidirectional full-bridge dc–dc converter with high conversion ratio, high output power, and soft start-up capability is proposed. The use of a capacitor, a diode, and a flyback converter can clamp the voltage spike caused by the current difference between the currentfed inductor and leakage inductance of the isolation transformer, and can reduce the current flowing through the active switches at the current-fed side.
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.; Nielsen, Henning R.
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......, respectively. Furthermore, the method to increase the number of input ports, the magnetic integration structure, and ground loop decoupling are discussed. Experimental results from the lab prototype converter with two DC voltage sources verify the validity of the theoretical analysis and design of the...
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.; Nielsen, Henning R.
2012-01-01
In this paper, a new two-input isolated boost dc-dc converter based on a distributed multi-transformer structure which is suitable for hybrid renewable energy systems is investigated and designed. With a novel transformer winding-connecting strategy, the two input ports can be decoupled completely...... powers of each transformer and rectifier are both reduced by four times. Furthermore, some special issues on converter design, such as increasing number of the input ports, the magnetic integration and the ground loop decoupling are discussed. A 2 kW prototype was built and tested. Experiments on the...
Directory of Open Access Journals (Sweden)
ANIL KUMAR REDDY.K, SIRISHA.S
2013-08-01
Full Text Available Abstract:zero-voltage-switching (ZVS dc?dc converter with specific voltage gain is proposed . The specific voltage is utilized for inverter operation for supplying 3-phase domestic load. It consists of a ZVS boost converter stage and a ZVS half-bridge converter stage and two stages are merged into a single stage. The ZVS boost converter stage provides a continuous input current and ZVS operation of the power switches. The ZVS half-bridge converter stage provides a high voltage gain. The principle of operation and system analysis are presented. The specific voltage is used to obtain a 200 volts Line to Line RMS AC supply through inverter operation. The supply is in turn used for a 3-Phase load like operation and speed control of 3-Phase Squirrel cage Induction motor. Keywords: Boost converter, Zero voltage switching, Coupled inductor, Specific voltage gain, Soft switching technique, Inverter, Speed control of Induction motor.
Ebrahim Babaei; Azadeh Mofidi; Sara Laali
2015-01-01
In the high voltage dc-dc boost converters, the energy transmission modes are divided into continuous conduction mode (CCM) and discontinuous conduction mode (DCM). In addition, these modes are also divided into two different modes: complete inductor supply mode (CISM) and incomplete inductor supply mode (IISM). In this paper, the operation of the boost dc-dc converter with high voltage gain is analyzed. Firstly, the energy transmission process between CCM and DCM is analyzed. Then, this pro...
Directory of Open Access Journals (Sweden)
Pui-Sun Lei
2015-01-01
Full Text Available This Letter presents a low start-up voltage dc–dc converter for low-power thermoelectric systems which uses a native n-type MOS transistor as the start-up switch. The start-up voltage of the proposed converter is 300 mV and the converter does not need batteries to start up. The negative voltage control is proposed to reduce the leakage current caused by native n-type transistor and increase the efficiency. The proposed converter was designed using standard 0.18 µm CMOS process with chip size of 0.388 mm^2. The peak efficiency is 63% at load current of 1.5 mA. The proposed converter provides output voltage >1 V at maximum load current of 3.2 mA.
International Nuclear Information System (INIS)
Research highlights: ? Hybrid electric power system for a real surface tramway. ? Hybrid system based on PEM fuel cell with dc/dc converter and Ni-MH battery. ? New control strategy for the energy management of the tramway. ? Hybrid system demonstrated to meet appropriate driving cycle of the tramway. -- Abstract: This paper presents a hybrid electric power system for a real surface tramway. The hybrid system consists of two electrical energy sources integrating a single dc/dc converter to provide the power demanded by the tramway loads (four electric traction motors and auxiliary services): (1) a Polymer Electrolyte Membrane (PEM) fuel cell (FC) as the primary and (2) a rechargeable Ni-MH battery as electrical energy storage to supplement the FC over the driving cycle. According to the requirements of the real driving cycle of the tramway, it was considered a 200 kW PEM FC system with two FCs connected in parallel and a 34 Ah Ni-MH battery. The PEM FC and Ni-MH battery models were designed from commercially available components. The power conditioning system provides the appropriate power for the tramway. It is composed of: (1) a unique dc/dc boot converter which adapts the FC output voltage to the 750 V traction standard dc bus; (2) three phase inverters to drive properly each electric motors; and (3) a braking chopper to dissipate excess of regenerative braking energy. Suitable state machine control architecture is presented for the hybrid system, its objective being to provide demanded power by the driving cycle, optimizing the energy generated. Following this objective, a new state machine control strategy based on eight states decides the operating point of each component of the system and a cascade control structure allows achieving the operating points determined by the strategy. Simulation results of the real driving cycle of the tramway check the adequacy of the hybrid electric power system.
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.
SPECTRAL ANALYSIS OF BUCK AND SEPIC CONVERTERS
Directory of Open Access Journals (Sweden)
CHAKIB ALAOUI
2011-02-01
Full Text Available Switched mode power converters generate harmonic currents, which will be injected into the utility grid, causing distortion of the utility waveform. They also become a source for the generation of EMI, which may affect the communication systems. This work is about the design and evaluation of the two most frequently used SMPS used in step down mode of operation: the Buck converter and the Sepic converter working in step-down mode of operation. These converters were designed using optimized equations for their components ratings. Simulation results show that although the Buck output voltage is low in harmonics, it has high harmonic contents in currents circulating in its inductor and diode, and hence requires strong filtering. The Sepic converterhas lower harmonic contents than the Buck converter.
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.
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.
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)
Sergio Ignacio Serna-Garces
2013-10-01
Full Text Available A previous article has presented the members of the asymmetrical interleaved dc/dc switching converters family as very appropriate candidates to interface between photovoltaic or fuel cell generators and their loads because of their reduced ripple and increased current processing capabilities. After a review of the main modeling methods suitable for high-order converters operating, as the asymmetrical interleaved converters (AIC ones, in discontinuous current conduction mode a full-order averaged model has been adapted and improved to describe the dynamic behavior of AIC. The excellent agreement between the mathematical model predictions, the switched simulations and the experimental results has allowed for satisfactory design of a linear-quadratic regulator (LQR in a fuel-cell application example, which demonstrates the usefulness of the improved control-oriented modeling approach when the switching converters operate in discontinuous conduction mode.
Directory of Open Access Journals (Sweden)
R. Seyezhai
2012-06-01
Full Text Available In this paper, a soft-switched Interleaved DC-DC Boost Converter (IBC for fuel cell is simulated and implemented. The proposed two-phase IBC circuit consists of two identical boost converter connected in parallel and are controlled by interleaved switching signals. But in the conventional IBC switching loss increases with the number of switching devices. To solve this problem, this paper has proposed a soft switched IBC. Detailed analysis has been done to investigate the benefits of soft-switched IBC compared to that of conventional uncoupled and directly coupled IBC. The converter circuit is constructed using power MOSFET as power switch. The PWM is generated by PIC18F4450 microcontroller. In this paper, the analysis of the converter is presented which is verified by the results of simulation and experimentation.
Directory of Open Access Journals (Sweden)
R. Seyezhai
2012-09-01
Full Text Available In this paper, a soft-switched Interleaved DC-DC Boost Converter (IBC for fuel cell is simulated and implemented. The proposed two-phase IBC circuit consists of two identical boost converter connected in parallel and are controlled by interleaved switching signals. But in the conventional IBC switching loss increases with the number of switching devices. To solve this problem, this paper has proposed a soft switched IBC. Detailed analysis has been done to investigate the benefits of soft-switched IBC compared to that of conventional uncoupled and directly coupled IBC. The converter circuit is constructed using power MOSFET as power switch. The PWM is generated by PIC18F4450 microcontroller. In this paper, the analysis of the converter is presented which is verified by the results of simulation and experimentation.
Lina Morales Laguado; Harold Chamorro; Jairo Soriano
2010-01-01
This document proposes analysing and designing two control strategies for permanent current DC-DC buck converter. These kinds of electronic devices convert a constant-voltage to a lower constant-voltage (nonlinearity characteristics being demonstra- ted). Two nonlinear control techniques are shown. The first is a conventional optimal proportional error and integral error (PI) controller based on minimising integral of time per squared errors (ITSE) criteria. A model of the plant at ...
DEFF Research Database (Denmark)
Mira Albert, Maria del Carmen; Zhang, Zhe; Knott, Arnold; Andersen, Michael A. E.
2015-01-01
DC microgrids or nanogrids have attracted increasing research interest in recent years. Therefore, as a critical component, dc-dc converters with multiple inputs are required. In this paper, a dual-input interleaved buck/boost converter is proposed and its corresponding power flow control methods are analyzed and designed accordingly. Furthermore, the design guidelines are discussed. Finally, in order to verify the validity of this study, the measurement results are presented.
Katayama, Noboru; Kogoshi, Sumio
A fuel cell/electric double layer capacitor hybrid power source using a multi-port bidirectional DC-DC converter has been developed to reduce load variations for the purpose of extending fuel cell life. The proposed converter operates to maintain the fuel cell current, load voltage and bus voltage at constant values with a digital signal processor. The effect of the proposed converter is evaluated. The charging or discharging current of the EDLC rapidly changes along with step loading, and the voltage and current of the fuel cell are maintained at the constant values. Short-time transient responses show that the fuel cell current ripples 0.35 A at 1 A load change in 6 ms.
DEFF Research Database (Denmark)
Meng, Lexuan; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez; Guerrero, Josep M.
2015-01-01
energy losses, this paper proposes a tertiary control level including an optimization method for achieving efficient operation. As the efficiency of each converter changes with the output power, VR values are set as decision variables for modifying the power sharing ratio among converters. Genetic...... algorithm is used in searching for a global efficiency optimum. In addition, a secondary control level is added to regulate the output voltage drooped by the VRs. However, system dynamics is affected when shifting up/down the VR references. Therefore, a secondary control for system damping is proposed and......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...
International Nuclear Information System (INIS)
The objective of this study was to increase the output current and power in a piezoelectric transformer (PT)-based DC/DC converter by using a cooling system. It is known that the output current of a PT is limited by temperature build-up because of losses, especially when driving at high vibration velocity. Although connecting different inductive circuits at the PT secondary terminal can increase the output current, the root cause of the temperature build-up problem has not yet been solved. This paper presents a study of a PT with cooling system in a DC/DC converter with a commonly used full-bridge rectifier and current-doubler rectifier. The advantages and disadvantages of the proposed technique were investigated. A theoreticalâ€“phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as heat generation increases the losses. In our design, the maximum output current capacity can increase by 100% when the temperature of operation of the PT is kept below 55â€‰Â° C. The study comprises a theoretical part and experimental proof-of-concept demonstration of the proposed design method. (paper)
Olivar, Gerard
1997-01-01
Esta tesis estudia el fenómeno del caos en las ecuaciones que modelan un convertidor buck con control PWM. Desde el punto de vista matemático, contribuye al estudio de los sistemas lineales a trozos tridimensionales, con émfasis en las perspectivas geométrica y de cálculo numérico. Se consiguen resultados analíticos pero, finalmente, deben emplearse métodos numéricos para calcular efectivamente las órbitas periódicas, bifurcaciones, variedades invariantes y cuencas de atracción. Desde el punt...
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)
New non-linear control strategy for non-isolated DC/DC converter with high voltage ratio
International Nuclear Information System (INIS)
In this paper, a non-isolated DC/DC converter with high voltage ratio is proposed to allow the interface between a low voltage power source like fuel cell and a high voltage DC bus. To take into account the low voltage-high density characteristics of power sources, a cascaded structure composed of two sub-converters has been chosen and allows obtaining a high voltage ratio. The choice of each sub-converter is based on the requirements of the source and its performances. Consequently, we have chosen a three-interleaved boost converter as the 1st sub-converter whereas the 2nd sub-converter is a three-level boost converter. The control of the whole system is realized thanks to energetic trajectories planning based on flatness properties of the system. The control of both the current and the balance of voltage across the output serial capacitors of the three-level boost converter is ensured by non-linear controllers based on a new non-linear model. Experimental results allow validating the proposed power architecture and its associated control.
Dual-Input Isolated Full-Bridge Boost DC-DC Converter Based on the Distributed Transformers
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius
2012-01-01
In this paper, a new two-input isolated boost dc-dc converter based on a distributed multi-transformer structure which is suitable for hybrid renewable energy systems is investigated and designed. With a novel transformer winding-connecting strategy, the two input ports can be decoupled completely, so the proposed converter can draw the power from the two different dc sources, which have low output voltage, and transfer it to the dc bus, which has high voltage, separately or simultaneously. The detailed operation principles of the proposed converter have been analyzed in the dual-input mode and the single-input mode, respectively. The main advantage of the proposed topology is that the four transformers and the secondary rectifiers are fully utilized whether the converter is connected with two input power sources or only one input. Although the four transformers are employed, the nominal powers of each transformer and rectifier are both reduced by four times. Furthermore, some special issues on converter design, such as increasing number of the input ports, the magnetic integration and the ground loop decoupling are discussed. A 2 kW prototype was built and tested. Experiments on the converter’s steady-state and transient operations verified the validity of the analysis and design.
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe
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) based capacitive incremental actuator, which has the potential to be used in automotive (e.g., EVs), space 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 with the proposed design are provided
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 of the converter unaffected or to improve the quality of the output current under the fault condition. The feasibility of the proposed fault detection and fault-tolerant methods are verified by simulations and experiments.
Transient Performance Improvement Circuit (TPIC)s for DC-DC converter applications
Lim, Sungkeun
Gordon Moore famously predicted the exponential increase in transistor integration and computing power that has been witnessed in recent decades [1]. In the near future, it is expected that more than one billion transistors will be integrated per chip, and advanced microprocessors will require clock speeds in excess of several GHz. The increasing number of transistors and high clock speeds will necessitate the consumption of more power. By 2014, it is expected that the maximum power consumption of the microprocessor will reach approximately 150W, and the maximum load current will be around 150A. Today's trend in power and thermal management is to reduce supply voltage as low as possible to reduce delivered power. It is anticipated that the Intel cores will operate on 0.8V of supply voltage by 2014 [2]. A significant challenge in Voltage Regulator Module (VRM) development for next generation microprocessors is to regulate the supply voltage within a certain tolerance band during high slew rate load transitions, since the required supply voltage tolerance band will be much narrower than the current requirement. If VR output impedance is maintained at a constant value from DC to high frequency, large output voltage spikes can be avoided during load cur- rent transients. Based on this, the Adaptive Voltage Position (AVP) concept was developed to achieve constant VR output impedance to improve transient response performance [3]. However, the VR output impedance can not be made constant over the entire frequency range with AVP design, because the AVP design makes the VR output impedance constant only at low frequencies. To make the output impedance constant at high frequencies, many bulk capacitors and ceramic capacitors are required. The tight supply voltage tolerance for the next generation of microprocessors during high slew rate load transitions requires fast transient response power supplies. A VRM can not follow the high slew rate load current transients, because 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 designed to improve the performance of an LDO regulator during output current transients. A TPIC fo
Directory of Open Access Journals (Sweden)
Jaw-Kuen Shiau
2014-08-01
Full Text Available The power converter is one of the essential elements for effective use of renewable power sources. This paper focuses on the development of a circuit simulation model for maximum power point tracking (MPPT evaluation of solar power that involves using different buck-boost power converter topologies; including SEPIC, Zeta, and four-switch type buck-boost DC/DC converters. The circuit simulation model mainly includes three subsystems: a PV model; a buck-boost converter-based MPPT system; and a fuzzy logic MPPT controller. Dynamic analyses of the current-fed buck-boost converter systems are conducted and results are presented in the paper. The maximum power point tracking function is achieved through appropriate control of the power switches of the power converter. A fuzzy logic controller is developed to perform the MPPT function for obtaining maximum power from the PV panel. The MATLAB-based Simulink piecewise linear electric circuit simulation tool is used to verify the complete circuit simulation model.
International Nuclear Information System (INIS)
The solar energy has been drawing attention of the whole world as a clean and infinite energy, since the globe resource, the globe ecology and so on came into question. The wide applications of the solar energy are being expected in a range from electric power plants to household systems. But the output power induced in the photovoltaic modules is influenced by an intensity of the solar radiation, a temperature of the solar cells and so on, so the various useful forms of the solar energy are being proposed for a purpose of stable power supply. a system described in this paper is a small scaled photovoltaic system with storage batteries. This paper describes the theoretical analyses of the photovoltaic system using a resonant DC-DC converter in order to clarify a desirable circuit condition, besides the experimental results of the battery charging characteristics are presented
Shimer, Daniel W. (Danville, CA); Lange, Arnold C. (Livermore, CA)
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.
Shimer, D.W.; Lange, A.C.
1995-05-23
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. 5 Figs.
Closed Loop DC-DC Boost Converter with Inverter for Small Scale Generation Plant
Manish Agarwal; Sanjeev Gupta; P.Phulambrikar
2014-01-01
In this paper implements the single phase two level PWM inverter by using DC converter. DC voltage is boosted using dc to dc boost converter with the help of close loop topology. Here converter will be used to convert 24 volts DC voltage to 373 volts. The boosted DC voltage is converted in to AC with help of PWM inverter. Boosted DC voltage is fed with the inverter and that converts DC voltage into AC voltage. The cascaded H-Bridge type of inverter is used to achieve AC output voltage. The ou...
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
Advanced Control for Very Fast DC-DC Converters Based on Hysteresis of the C-out Current
Huerta Oliveres, Santa Concepción; Soto de Pecho, Andrés; Alou Cervera, Pedro; Oliver Ramírez, Jesús Angel; García Suárez, Oscar; Cobos Márquez, José Antonio
2013-01-01
The bandwidth achievable by using voltage mode control or current mode control in switch-mode power supply is limited by the switching frequency. Fast transient response requires high switching frequency, although lower switching frequencies could be more suitable for higher efficiency. This paper proposes the use of hysteretic control of the output capacitor $(C_{out})$ current to improve the dynamic response of the buck converter. An external voltage loop is required to accurately regulate ...
Kosenko Roman; Liivik Liisa; Chub Andrii; Velihorskyi Oleksandr
2015-01-01
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 ...
Self-oscillating Galvanic Isolated Bidirectional Very High Frequency DC-DC Converter
DEFF Research Database (Denmark)
Pedersen, Jeppe Arnsdorf; Madsen, Mickey Pierre
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 synchronous. This increases the complexity of the gate drives, which in this paper is solved by using a self-oscillating gate drive. A bidirectional converter has been implemented and is described in this paper; the converter reaches efficiencies above 80% in forward conduction mode and 73.5% in reverse conduction mode. The designed converter operates at a switching frequency of 35.6 MHz, which is well within the VHF range. The same converter is also implemented with PCB embedded inductors to minimize cost and the physical volume of the total converter.
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.
Continuation of periodic orbits in a ZAD-strategy controlled buck converter
International Nuclear Information System (INIS)
This paper concerns the dynamics of a Zero Average Dynamics (ZAD) controlled DC-DC Buck converter. We study the continuation problem of periodic orbits in a periodically forced piecewise-smooth system through the ranges of existence and stability. These orbits can have different configuration and periodicity, and they end in a transition to chaotic bands when a parameter is varied. Three assumptions (a symmetry assumption, a zero-average assumption and a regulation assumption) allows existence ranges to be predicted analytically, and there is only a final efficient numerical step. Stability is checked through Floquet exponents, which are also analytically computed
DC-DC Converters Using PID Controller and Pulse Width Modulation Technique
Directory of Open Access Journals (Sweden)
R.Sudha
2014-01-01
Full Text Available This paper presents a boost converter along with a flyback converter. The Zero Voltage Switching (ZVS technique is used to achieve soft switching. A bidirectional boost converter is connected with an output module as a Parallel Input Serial Output configuration. The flyback converter with Voltage Doubler Rectifier (VDR acts as an output module. This connection makes a bidirectional boost converter an active clamp circuit which is connected to the output side in order to extend the step up ratio. A converter with active clamp technique is used to recycle the leakage energy, to eliminate voltage spike due to coupled inductors and also to provide a mechanism to achieve ZVS. To overcome the efficiency degradation during light load due to load dependent soft switching of the ZVS, a control method using Pulse Width Modulation (PWM proportional to the load current is used.
Closed Loop DC-DC Boost Converter with Inverter for Small Scale Generation Plant
Directory of Open Access Journals (Sweden)
Manish Agarwal
2014-09-01
Full Text Available In this paper implements the single phase two level PWM inverter by using DC converter. DC voltage is boosted using dc to dc boost converter with the help of close loop topology. Here converter will be used to convert 24 volts DC voltage to 373 volts. The boosted DC voltage is converted in to AC with help of PWM inverter. Boosted DC voltage is fed with the inverter and that converts DC voltage into AC voltage. The cascaded H-Bridge type of inverter is used to achieve AC output voltage. The output of inverter is given to low-pass filter which will give 260 volts (RMS AC , 50Hz pure sinusoidal output voltage & finally this output is given to the load.
Analysis of a Multilevel Dual Active Bridge (ML-DAB DC-DC Converter Using Symmetric Modulation
Directory of Open Access Journals (Sweden)
M. A. Moonem
2015-04-01
Full Text Available Dual active bridge (DAB converters have been popular in high voltage, low and medium power DC-DC applications, as well as an intermediate high frequency link in solid state transformers. In this paper, a multilevel DAB (ML-DAB has been proposed in which two active bridges produce two-level (2L-5L, 5L-2L and 3L-5L voltage waveforms across the high frequency transformer. The proposed ML-DAB has the advantage of being used in high step-up/down converters, which deal with higher voltages, as compared to conventional two-level DABs. A three-level neutral point diode clamped (NPC topology has been used in the high voltage bridge, which enables the semiconductor switches to be operated within a higher voltage range without the need for cascaded bridges or multiple two-level DAB converters. A symmetric modulation scheme, based on the least number of angular parameters rather than the duty-ratio, has been proposed for a different combination of bridge voltages. This ML-DAB is also suitable for maximum power point tracking (MPPT control in photovoltaic applications. Steady-state analysis of the converter with symmetric phase-shift modulation is presented and verified using simulation and hardware experiments.
Phase-staggering control of a series-resonant DC-DC converter with paralleled power modules
Klaassens, J. Ben; Moize de Chateleux, Willem L. F. H. A.; van Wesenbeeck, M. P. N.
1988-04-01
A method of decreasing the ripple on the output voltage of high-power AC-DC or DC-DC series-resonant converters without increasing the internal converter frequency or the capacity of the energy storage elements is discussed. This improvement is accomplished by subdividing the converter into two or more series-resonant power modules operated with a constant relative phase shift (phase-staggering control). The method of eliminating the harmonic components in the input and output currents of the conversion system, without increasing the internal pulse frequency, is justified by Fourier analysis of the current waveforms. The frequency spectra of the source and output waveforms for the continuous and discontinuous resonant current mode are shifted to higher frequency ranges, as computations show for both one single module and multiple paralleled modules. Inadequacies in the phase-staggering control method applied to series-resonant converters are indicated in relation to the dominant harmonic component, in particular for two modules and supported by experimentally acquired waveforms. High-frequency current components to the source and to the load are reduced, resulting in smaller input and output filters. This improves the resolution of the control of the flow of energy from the source to the load, resulting in a faster system response.
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.
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.
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...
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
Today power converters are present in many commercial, medical and industrial applications. A lot of them are high power and high current applications. In order to increase power handling capability several transistors or diodes are paralleled often. However such paralleling may lead to converter...
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...
Design and Implementation of Power Flow Control for a novel Dual Input DC-DC Converter
DEFF Research Database (Denmark)
Taeed, Fazel; Ouyang, Ziwei
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 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 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.
High efficiency isolated DC/DC converter inherently optimized for fuel cell applications
DEFF Research Database (Denmark)
Petersen, Lars Press; Jensen, Lasse Crone
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 different topology not previous used for fuel cell applications with some clear advantages. Taking into account the I-V characteristics of the fuel cell only emphasized the performance of the proposed converter and reveals its self as an optimal candidate for the fuel cell application.
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
In this paper an isolated full bridge boost converter (IFBC) firstly is modeled. In the modeling part, a small signal equivalent of the converter is developed. From the small signal model, the converter transfer function is derived. Based on the obtained transfer function, challenges of controller design are discussed. In the next step a digital PI controller is designed and implemented in a FPGA to control the output voltage. Using the injection transformer method the open loop transfer function in closed loop is measured and modeling results are verified by experimental results. © 2013 IEEE.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2012-01-01
This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high-frequency tr......This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high......-frequency transformer; this structure minimizes the number of the switching transistors and their associate gate driver components. With phase-shift control strategy, all the switches are operated under zero-voltage switching (ZVS) condition. Furthermore, in order to optimize the converter performance and increase...
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; Andersen, Michael A. E.
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 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....
DEFF Research Database (Denmark)
Meng, Lexuan; Dragicevic, Tomislav
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 energy losses, this paper proposes a tertiary control level including an optimization method for achieving efficient operation. As the efficiency of each converter changes with the output power, VR values are set as decision variables for modifying the power sharing ratio among converters. Genetic algorithm is used in searching for a global efficiency optimum. In addition, a secondary control level is added to regulate the output voltage drooped by the VRs. However, system dynamics is affected when shifting up/down the VR references. Therefore, a secondary control for system damping is proposed and applied for maintaining system stability. Hardware-in-the-loop simulations are conducted to validate the effectiveness of this method. The results show that the system efficiency is improved by using tertiary optimization control and the desired transient response is ensured with system damping secondary control.
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.
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 Effective High Step-Up Interleaved DC-DC Converter Photovoltaic Grid Connection System
G. Lakpathi,; S. ManoharReddy,; K. Lakshmi Ganesh,; G. Satyanarayana,
2013-01-01
Within the photovoltaic (PV) power generation systems in the market, the ac PV module has shown obvious growth. However, a high voltage gain converter is concentrate for the module’s grid connection with dc-ac inverter. This paper proposed a converter that employs a floating active switch to isolate energy from the PV panel when the ac module is OFF; this particular design protects installers and users from electrical hazards. Without extreme duty ratios and numerous turns-ratio of a coupled ...
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2013-01-01
Energy production from renewable energy sources is continuously varying, for this reason energy storage is becoming more and more important as the percentage of green energy increases. Newly developed fuel cells can operate in reverse mode as electrolyzer cells; therefore, they are becoming an...... attractive technology for energy storage grid-tie applications. In this application dc-dc converter optimization is very challenging due to the large voltage range that the converter is expected to operate. Moreover, the fuel-electrolyzer cell side of the converter is characterized by low voltage and high...... current. Dc-dc converter efficiency plays a fundamental role in the overall system efficiency since processed energy is always flowing through the converter; for this reason, loss analysis and optimization are a key component of the converter design. The paper presents an isolated full bridge boost dc...
Very High Frequency Resonant DC/DC Converters for LED Lighting
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
with 40 V input and 15 V output are made. The simulation shows possibility of achieving efficiency up to 87 % even with a HEXFET Power MOSFET. Three prototypes of the simulated converter are implemented showing good correlation with simulations. The prototypes have efficiencies up to 84 % and power...
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.; Schmidt, Jacob D.; Nielsen, Henning R.
Abstract-In this paper, an extended run time DC UPS system structure with fuel cell and supercapacitor is investigated. A wide input range bi-directional dc-dc converter is described along with the phase-shift modulation scheme and phase-shift with duty cycle control, in different modes. The...
DEFF Research Database (Denmark)
Schaltz, Erik; Li, Zhihao; Onar, Omer; Khaligh, Alireza
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...
Speed control of synchronous machine by changing duty cycle of DC/DC buck converter
Rashid Al Badwawi; Mohammad Abusara; Tapas Mallick
2015-01-01
Renewable energies such as wind or solar energy are naturally intermittent and can create technical challenges to interconnected grid in particular with high integration amounts. In addition, if wind or solar is used to supply power to a stand-alone system, continuous power supply will be met only if sufficient energy storage system is available. The global penetration of renewable energy in power systems is increasing rapidly especially wind and solar photovoltaic (PV) systems. Hybrid wind a...
Speed control of synchronous machine by changing duty cycle of DC/DC buck converter
Directory of Open Access Journals (Sweden)
Rashid Al Badwawi
2015-11-01
Full Text Available Renewable energies such as wind or solar energy are naturally intermittent and can create technical challenges to interconnected grid in particular with high integration amounts. In addition, if wind or solar is used to supply power to a stand-alone system, continuous power supply will be met only if sufficient energy storage system is available. The global penetration of renewable energy in power systems is increasing rapidly especially wind and solar photovoltaic (PV systems. Hybrid wind and solar PV generation system becomes very attractive solution in particular for stand-alone applications. It can provide better reliability since the weakness of one system could be complemented by the strength of the other one. When wind energy is integrated into grid, maximum power point tracking control could be used to optimize the output of wind turbine. In variable speed wind turbine, the turbine speed is varied according to the wind speed. This paper presents a comparison between two methods of controlling the speed of a wind turbine in a microgrid namely; Proportional-Integral (PI control of the tip speed ratio and stored power curve. The PI method provides more controllability, but it requires an anemometer to measure the wind speed. The stored power curve method, however, is easier to implement, but the amount of energy extracted can be less. The system has been modelled using Matlab/Simulink.
Mari, Federico; Melatti, Igor; Salvo, Ivano; Tronci, Enrico
2011-01-01
Many Embedded Systems are indeed Software Based Control Systems (SBCSs), that is control systems whose controller consists of control software running on a microcontroller device. This motivates investigation on Formal Model Based Design approaches for automatic synthesis of SBCS control software. In previous works we presented an algorithm, along with a tool QKS implementing it, that from a formal model (as a Discrete Time Linear Hybrid System, DTLHS) of the controlled syst...
Scientific Electronic Library Online (English)
Carlos Alejandro, Ramírez; Andrés Julián, Saavedra-Montes; Carlos Andrés, Ramos-Paja.
2014-01-01
Full Text Available Este artículo presenta una revisión de la literatura sobre sistemas eólicos de micro generación. La revisión analiza cuatro tópicos: la topología del sistema, su modelado, el diseño de los convertidores de potencia y el control de los mismos. Finalmente, la revisión resalta los problemas de investig [...] ación abiertos, así como las oportunidades para mejorar soluciones comúnmente utilizadas Abstract in english This paper presents a literature review analyzing four topics concerning wind systems for micro-generation: system topologies, system modeling, power converters design, and power converter controllers. The review also reveals the open research problems in the literature, and the opportunities to imp [...] rove commonly adopted solutions
A New Active Soft Switching Technique for Pulse Width Modulated Full Bridge DC-DC Converters
Directory of Open Access Journals (Sweden)
Naga Brahmendra Yadav Gorla
2014-02-01
Full Text Available A new active soft switching circuit for Zero Voltage Switched Pulse Width Modulated (ZVS-PWM full bridge converter is presented in this paper. The proposed circuit has two auxiliary circuit cells (Auxiliary circuit cell-1, Auxiliary circuit cell-2, one for each ground referred active switch. Auxiliary circuit cell consists of an active switch, a diode, a resonant inductor and a capacitor, and a coupled winding derived from main power transformer. Auxiliary circuit when gated properly creates zero voltage across the main switch during its turn-on. Winding coupled to the power transformer helps in resetting auxiliary inductor current to zero and hence turn-off of auxiliary switch is lossless. Steady state operation of proposed circuit with necessary analytical expressions is presented. Circuit simulation results of the proposed active soft switched ZVS-PWM full bridge converter are presented.
Design and implementation of adaptive slope compensation in current mode DC-DC converter
International Nuclear Information System (INIS)
To improve the compensation for the inherent instability in a current mode converter, the adaptive slope compensation, giving attention to the problems of the traditional compensation on compensation accuracy, loading capability and turning jitter, is presented. Based on the analysis of current loop, by detecting the input and output voltage, converting the adaptive slope compensation current, the compensation of the current loop is optimized successfully. It can not only improve the compensation accuracy but also eliminate the over compensation, the turning jitter and the poor loading capability in the reported slope compensation. A power supply chip with adaptive slope compensation has been fabricated in a 0.35 ?m CMOS process. The measurement results show that the chip starts up and operates steadily with the constant current limit under conditions of 5 V input voltage, from 10% to 100% duty cycle. (semiconductor integrated circuits)
A New Active Soft Switching Technique for Pulse Width Modulated Full Bridge DC-DC Converters
Naga Brahmendra Yadav Gorla; N. Lakshmi Narasamma
2014-01-01
A new active soft switching circuit for Zero Voltage Switched Pulse Width Modulated (ZVS-PWM) full bridge converter is presented in this paper. The proposed circuit has two auxiliary circuit cells (Auxiliary circuit cell-1, Auxiliary circuit cell-2), one for each ground referred active switch. Auxiliary circuit cell consists of an active switch, a diode, a resonant inductor and a capacitor, and a coupled winding derived from main power transformer. Auxiliary circuit when gated properly create...
Design and Implementation of high frequency transformer for SMPS Based flyback DC-DC converter
Directory of Open Access Journals (Sweden)
Prashanth R.S.
2012-12-01
Full Text Available In switch mode power supplies (SMPS, flyback converters are very popular because of, design simplicity, low cost, multiple isolated outputs, high output voltages and high efficiency. They are preferred especially for low power applications. In this paper we have presented the design of transformer for variable DC input (18V to 60V to 12V DC output. And observed the wave form across the switch, primary & secondary of the transformer.
Optimal Design and Tradeoff Analysis of Planar Transformer in High-Power DC–DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2012-01-01
The trend toward high power density, high operating frequency, and low profile in power converters has exposed a number of limitations in the use of conventional wire-wound magnetic component structures. A planar magnetic is a low-profile transformer or inductor utilizing planar windings, instead of the traditional windings made of Cu wires. In this paper, the most important factors for planar transformer (PT) design including winding loss, core loss, leakage inductance, and stray capacitance ha...
Design and Implementation of high frequency transformer for SMPS Based flyback DC-DC converter
Prashanth R.S.; C.M.Tavade; L.M.Deshpande; Hameed Miyan
2012-01-01
In switch mode power supplies (SMPS), flyback converters are very popular because of, design simplicity, low cost, multiple isolated outputs, high output voltages and high efficiency. They are preferred especially for low power applications. In this paper we have presented the design of transformer for variable DC input (18V to 60V) to 12V DC output. And observed the wave form across the switch, primary & secondary of the transformer.
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe
2013-01-01
Energy production from renewable energy sources is continuously varying, for this reason energy storage is becoming more and more important as the percentage of green energy increases. Newly developed fuel cells can operate in reverse mode as electrolyzer cells; therefore, they are becoming an attractive technology for energy storage grid-tie applications. In this application dc-dc converter optimization is very challenging due to the large voltage range that the converter is expected to operate. Moreover, the fuel-electrolyzer cell side of the converter is characterized by low voltage and high current. Dc-dc converter efficiency plays a fundamental role in the overall system efficiency since processed energy is always flowing through the converter; for this reason, loss analysis and optimization are a key component of the converter design. The paper presents an isolated full bridge boost dc-dc converter (IFBBC) designed for this new application focusing on losses analysis. The system topology is briefly discussed and the major concerns related to the system, cells stacks and converter operating points are analyzed. The dc-dc converter losses are modeled and presented in detail; the analysis is validated on adc-dc converter prototype rated at 6 kW 30-80 V 0-80 A on the low voltage side and 700-800 V on the high voltage side (for a grid-tie application). The prototype is based on fully planar magnetic, Si MOSFETs, Si IGBTs and SiC diodes; efficiencies up to ~96.5% and ~97.8% were demonstrated depending on the converter operating point.
Complete bifurcation analysis of DC-DC converters under current mode control
International Nuclear Information System (INIS)
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
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)
A fast dynamic response dc-dc converter for high voltage applications
International Nuclear Information System (INIS)
This paper present a fast dynamic response de-de converter for high voltage application such as medical use X-ray generator. In the proposed de-de converter a zero-current switching series resonant inverter is used to drive input terminals of voltage multiplier circuit. The zero-current switching series resonant inverter operates at fixed frequency and duly ratio. A control circuit is used at the lower arm of the inverter, to control the effective input voltage across the inverter. At the turn on the inverter is supplied with maximum effective input voltage, which results in quick rise-up of the output voltage. As the output voltage approaches to 80% of it target voltage, the effective input voltage is reduced to a value which corresponds to the target output voltage, as a result the rise rate of the output voltage becomes slow and overshoot is avoided. The effectiveness of the proposed control scheme has been confirmed experimentally with a laboratory scale- down prototype. (author)
DEFF Research Database (Denmark)
Zhang, Zhe; Ouyang, Ziwei
2012-01-01
Electrical power system in future uninterruptible power supply (UPS) or electrical vehicle (EV) may employ hybrid energy sources, such as fuel cells and super-capacitors. It will be necessary to efficiently draw the energy from these two sources as well as recharge the energy storage elements by the DC bus. In this paper, a bidirectional isolated DC-DC converter controlled by phase-shift and duty cycle for the fuel cell hybrid energy system is analyzed and designed. The proposed topology minimizes the number of switches and their associated gate driver components by using two high frequency transformers which combine a half-bridge circuit and a full-bridge circuit together on the primary side. The voltage doubler circuit is employed on the secondary side. The current-fed input can limit the input current ripple that is favorable for fuel cells. The parasitic capacitance of the switches is used for zero voltage switching (ZVS). Moreover, a phase-shift and duty cycle modulation method is utilized to control thebidirectional power flow flexibly and it also makes the converter operate under a quasi-optimal condition over a wide input voltage range. This paper describes the operation principle of the proposed converter, the ZVS conditions and the quasi-optimal design in depth. The design guidelines and considerations about the transformers and other key components are given. Finally, a 1- kW 30~50-V-input 400-V-output laboratory prototype operating at 100 kHz switching frequency is built and tested to verify the effectiveness of the presented converter.
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...
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...
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%.
Development of TMS320F2810 DSP Based Bidirectional buck-boost Chopper
Directory of Open Access Journals (Sweden)
Mr. K.S. Chakradhar*1,
2014-06-01
Full Text Available A DC - DC converter is an electronic circuit which converts a source of direct current (DC from one voltage level to another. It is a class of power converter. One common application of DC - DC converters is DC motor control. The Buck - Boost Chopper is a type of DC - DC converter. They are static devices which are used to obtain variable DC voltage from the source of constant DC voltage. Besides the saving in power, Buck-Boost choppers offer greater efficiency, faster response, lower maintenance, smooth control and small size. Even though Buck Boost choppers have several advantages, they can't transfer power from either sides. So a unidirectional DC/DC converter is designed to flow energy on both sides by replacing diodes with controllable switch forming a Bidirectional DC/DC converter. The output DC level is controlled by varying the time for which the supply is connected to the circuit.
Sergio Serna; Roberto Giral; Javier Calvente; Carlos Andres Ramos-Paja; Eliana Arango
2012-01-01
A novel asymmetrical interleaved dc/dc switching converters family intended for photovoltaic and fuel cell applications is presented in this paper. The main requirements on such applications are small ripples in the generator and load, as well as high voltage conversion ratio. Therefore, interleaved structures and voltage multiplier cells have been asymmetrically combined to generate new converters, which inherently operate indiscontinuous conduction mode. The novel family is derived from boo...
DEFF Research Database (Denmark)
Schaltz, Erik; Li, Zhihao; Onar, Omer; Khaligh, Alireza
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 converter is capable of bi-directional operation and is responsible for power diversification and optimization. A fixed switching frequency strategy is considered to control its operating modes. A portion o...
Scientific Electronic Library Online (English)
Andrés Mauricio, López-Cañón; Rafael Fernando, Diez-Medina; Gabriel, Perilla-Galindo; Diego Alejandro, Patiño-Guevara.
2012-06-01
Full Text Available Neste artigo analisa-se e desenha-se um conversor multinível em topologia tipo escada para una aplicação de alta voltagem (3000 V). Este conversor é comparado com outra estrutura conhecida chamada flying capacitors e mostra sua simplicidade na implementação e no controle. Adicionalmente, analisam as [...] quedas de voltagem a topologia tipo escada em função do número de celular e da corrente de carga. Por outro lado, implementa-se o conversor, que alcança satisfatoriamente 3000 V 100 mA e com os resultados obtidos validam-se as análises teóricas. O conversor é testado com dois tipos diferentes de condensadores e, assim, determina-se qual deles tem o melhor desempenho. Abstract in spanish En este artículo se analiza y se diseña un convertidor multinivel en topología escalera para una aplicación de alto voltaje (3.000 V). Este convertidor se compara con otra estructura conocida llamada flying capacitors y muestra su sencillez en la implementación y en el control. Adicionalmente, se an [...] alizan las caídas de voltaje de la topología escalera en función del número de celdas y de la corriente de carga. Por otro lado, se implementa el convertidor, que alcanza satisfactoriamente 3000 V 100 mA y con los resultados obtenidos se validan los análisis teóricos. El convertidor se prueba con dos tipos diferentes de condensadores y, así, se determina cuál de ellos tiene el mejor desempeño. Abstract in english This article analyzes and designs a ladder multilevel converter topology for a high voltage application (3000 V). This converter is compared to other well-known structures called Flying Capacitors showing its simplicity for implementation and control. In addition, an analysis of the voltage drop of [...] the ladder topology is carried out as a function of the number of cells and of the load current. Furthermore, the converter is implemented and successfully achieves 3000 V 100 mA. The theoretical analysis is validated by the results. The converter is tested with two different types of capacitors in order to determine which one offers a better performance.
Directory of Open Access Journals (Sweden)
M.Geetha
2012-05-01
Full Text Available This paper presents on a new high power full bridge isolated current fed dc/dc Converter with an active clamp. A proposed current fed dc/dc converter with high efficiency and voltage boosting capability is designed for use in the interface between a low voltage fuel cell source and a high voltage dc bus for inverters.ZVS scheme in all active switches is achieved for using a soft switching scheme. The switching losses and the conduction losses are reduced and the performance of the drive system should be increased from the proposed model. The proposed converter system is controlled by SPWM Technique. The simulation results are carried out and presented.
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.
Directory of Open Access Journals (Sweden)
Ebrahim Babaei
2015-06-01
Full Text Available In the high voltage dc-dc boost converters, the energy transmission modes are divided into continuous conduction mode (CCM and discontinuous conduction mode (DCM. In addition, these modes are also divided into two different modes: complete inductor supply mode (CISM and incomplete inductor supply mode (IISM. In this paper, the operation of the boost dc-dc converter with high voltage gain is analyzed. Firstly, the energy transmission process between CCM and DCM is analyzed. Then, this process is investigated between IISM and CISM. Moreover, the critical inductance between CCM and DCM in addition to CISM and IISM is calculated. Finally, in order to verify the presented theoretical issues, the simulation results in EMTDC/PSCAD software program are used.
Directory of Open Access Journals (Sweden)
Saritha Thomas
2014-09-01
Full Text Available This paper presents a soft-switching pulse width modulation (PWM non-isolated bi-directional dc–dc converter embedding an edge-resonant switched capacitor (ER-SWC cell. The conceptual dc–dc converter treated herein can achieve high-frequency zero-current soft-switching turn-on and zero-voltage soft-switching turn-off operations in the active switches. Those advantageous properties enable a wide range of soft-switching operations together with a high-voltage step- up conversion ratio with a reduced current stress. Circuit design guideline based on the soft-switching range is introduced; then, a theoretical analysis is carried out for investigating the step up voltage conversion ratio.
1 kW, 9 kV dc-dc converter module with time-sharing control of output voltage and input current
Energy Technology Data Exchange (ETDEWEB)
Borgatti, R.; Stefani, R.; Bressan, O.; Bicciato, F. [F.I.A.R. Electronic Systems Group, Milan (Italy). Avionics Div.; Tenti, P.; Rossetto, L. [Univ. of Padova (Italy). Dept. of Electrical Engineering
1993-10-01
The paper describes a dc-dc power module based on a single-stage current-fed converter structure. Control is made according to a time-sharing strategy allowing simultaneous regulation of output voltage and input current. This solution is suitable for high-performance space and avionic applications, giving high efficiency, compactness, and accuracy, speed and robustness of control. Theoretical analysis, design criteria, and experimental results are reported. Application to radar supplies is discussed.
Arshak, Khalil; Almukhtar, Basil
2000-01-01
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.
A prototype of a fuel cell PEM emulator based on a buck converter
Energy Technology Data Exchange (ETDEWEB)
Marsala, Giuseppe; Cirrincione, Maurizio; Miraoui, Abdellatif [FClab- SET, Universite de Technologie de Belfort-Montbeliard (UTBM), Belfort (France); Pucci, Marcello; Vitale, Gianpaolo [ISSIA-CNR (Institute on Intelligent Systems for the Automation), Via Dante, 12, Palermo (Italy)
2009-10-15
After a brief introduction about fuel cell systems, and their modelling, this paper proposes a possible solution to emulate a proton exchange membrane fuel cell (PEM-FC) system by using a DC-DC buck converter. The fuel cell system, including all its auxiliaries and related control systems, is emulated by a buck converter realized experimentally and controlled in the DSPACE environment. The realization of the buck converter allows the behaviour of any fuel cells to be easily emulated since only the modification of the control law of the switch is necessary. The proposed emulator can be applied easily to other fuel cell systems if the polarization curve has the same current rate and maximum power. In this way it is possible to utilize the converter and perform the necessary tests to optimize a fuel cell system by avoiding the waste of hydrogen and the purchase of cells as well as any cell damage. With regard to current other types of emulators, the one presented here has the following characteristics: (1) all the auxiliaries of the system have been considered, each including its own control system, as in a real FCS, (2) the converter is a classical buck converter with a free-wheeling diode and is designed to have a high bandwidth and to be practically always in conduction mode (discontinuous mode appears only at very low currents) (3) the voltage control is made by a space-state controller, able to fix properly the closed loop poles of the system, thus guaranteeing the desired bandwidth of the control system and (4) it can be used in laboratory as a stand-alone low-cost system for design and experimental purposes. (author)
A prototype of a fuel cell PEM emulator based on a buck converter
International Nuclear Information System (INIS)
After a brief introduction about fuel cell systems, and their modelling, this paper proposes a possible solution to emulate a proton exchange membrane fuel cell (PEM-FC) system by using a DC-DC buck converter. The fuel cell system, including all its auxiliaries and related control systems, is emulated by a buck converter realized experimentally and controlled in the DSPACE environment. The realization of the buck converter allows the behaviour of any fuel cells to be easily emulated since only the modification of the control law of the switch is necessary. The proposed emulator can be applied easily to other fuel cell systems if the polarization curve has the same current rate and maximum power. In this way it is possible to utilize the converter and perform the necessary tests to optimize a fuel cell system by avoiding the waste of hydrogen and the purchase of cells as well as any cell damage. With regard to current other types of emulators, the one presented here has the following characteristics: (1) all the auxiliaries of the system have been considered, each including its own control system, as in a real FCS, (2) the converter is a classical buck converter with a free-wheeling diode and is designed to have a high bandwidth and to be practically always in conduction mode (discontinuous mode appears only at very low currents) (3) the voltage control is made by a space-state controller, able to fix properly the closed loop poles of the system, thus guaranteeing the desired bandwidth of the control system and (4) it can be used in laboratory as a stand-alone low-cost system for design and experimental purposes.
Directory of Open Access Journals (Sweden)
Chien-Wei Ma
2013-03-01
Full Text Available This paper analyzes and simulates the Li-ion battery charging process for a solar powered battery management system. The battery is charged using a non-inverting synchronous buck-boost DC/DC power converter. The system operates in buck, buck-boost, or boost mode, according to the supply voltage conditions from the solar panels. Rapid changes in atmospheric conditions or sunlight incident angle cause supply voltage variations. This study develops an electrochemical-based equivalent circuit model for a Li-ion battery. A dynamic model for the battery charging process is then constructed based on the Li-ion battery electrochemical model and the buck-boost power converter dynamic model. The battery charging process forms a system with multiple interconnections. Characteristics, including battery charging system stability margins for each individual operating mode, are analyzed and discussed. Because of supply voltage variation, the system can switch between buck, buck-boost, and boost modes. The system is modeled as a Markov jump system to evaluate the mean square stability of the system. The MATLAB based Simulink piecewise linear electric circuit simulation tool is used to verify the battery charging model.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2013-01-01
This paper presents a new zero-voltage-switching (ZVS) isolated dc-dc converter which combines a boost halfbridge (BHB) cell and a full-bridge (FB) cell, so that two different type of power sources, i.e. both current-fed and voltage-fed, can be coupled effectively by the proposed converter for...... various applications, such as fuel cell and super-capacitor hybrid energy system. By fully using two high frequency transformers and a shared leg of switches, number of the power devices and associated gate driver circuits can be reduced. With phase-shift control, the converter can achieve ZVS turn-on of...
DEFF Research Database (Denmark)
Schaltz, Erik; Li, Zhihao
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 converter is capable of bi-directional operation and is responsible for power diversification and optimization. A fixed switching frequency strategy is considered to control its operating modes. A portion of New York City Cycle that includes these operation modes is used to perform the analyses.
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.
Sample-Data Modeling of a Zero Voltage Transition DC-DC Converter for On-Board Battery Charger in EV
Granados-Luna, Teresa R.; Ismael Araujo-Vargas; Perez-Pinal, Francisco J.
2014-01-01
Battery charger is a key device in electric and hybrid electric vehicles. On-board and off-board topologies are available in the market. Lightweight, small, high performance, and simple control are desired characteristics for on-board chargers. Moreover, isolated single-phase topologies are the most common system in Level 1 battery charger topologies. Following this trend, this paper proposes a sampled-data modelling strategy of a zero voltage transition (ZVT) DC-DC converter for an on-board ...
Accurate Sliding-Mode Control System Modeling for Buck Converters
DEFF Research Database (Denmark)
HÃ¸yerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.
2007-01-01
This paper shows that classical sliding mode theory fails to correctly predict the output impedance of the highly useful sliding mode PID compensated buck converter. The reason for this is identified as the assumption of the sliding variable being held at zero during sliding mode, effectively...... approach also predicts the self-oscillating switching action of the sliding-mode control system correctly. Analytical findings are verified by simulation as well as experimentally in a 10-30V/3A buck converter....
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius
2012-01-01
This paper presents a low-cost bidirectional isolated dc–dc converte, derived from dual-active-bridge converter for the power sources with variable output voltage like supercapacitors. The proposed converter consists of push-pull-forward circuit half-bridge circuit (PPFHB) and a high-frequency transformer; this structure minimizes the number of the switching transistors and their associate gate driver components. With phase-shift control strategy, all the switches are operated under zero-voltage switching (ZVS) condition. Furthermore, in order to optimize the converter performance and increase efficiency, optimal design methods and criteria are investigated, including coupled inductors design, bidirectional power flow analysis, harmonics analysis, and ZVS range extension. Based on all the optimal parameters, higher efficiency can be achieved. Finally, prototypes are built in laboratory controlled by digital signal processor for comparison purpose. Detailed test results verify the theoretical analysis and demonstrate the validity of optimization design method.
Two phase interleaved buck converter for driving high power LEDs
DEFF Research Database (Denmark)
Beczkowski, Szymon; Munk-Nielsen, Stig
2011-01-01
The goal of this paper is to evaluate an interleaved buck topology for driving high current light-emitting diodes. Low output capacitor value allows the use of non-electrolytic capacitors extending the lifetime of the converter. Converter is operated as a constant, regulated current source which...... increases luminous efficacy of LED compared to PWM dimmed system. Because of the low dynamic resistance of LEDs the duty cycle of the converter does not change greatly with controlled current. By setting the input voltage of the buck converter to around twice the voltage of diode strings, converter can be...
International Nuclear Information System (INIS)
A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented. By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA), the proposed circuit generates two zeros to realize high closed-loop stability. Meanwhile, full on-chip integration is also achieved due to its simple structure. Hence, the number of off-chip components and the board space is greatly reduced. The structure of the dual signal path OTA is also optimized to help get a better transition response. Implemented in a 0.5 ?m CMOS process, the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability. The test results show that both load and line regulations are less than 0.3%, and the output voltage can be recovered within 15 ?s for a 400 mA load step. Moreover, the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%. The efficiency of the whole chip can be up to 95%. (semiconductor integrated circuits)
Energy Technology Data Exchange (ETDEWEB)
Senouci, N.
1998-07-01
This work belongs to the European Barmint project which final goal is the realization of a micro-system, implanted in the human body, and devoted to the regulation of the blood pressure of patients. The aim of this thesis is the realization of the miniaturized power supply of this micro-system. The different approaches allowing to reach the required voltage levels from the 3.5 V initial level are analysed first. A solution based on the integration of DC-DC converters with their control loop has been retained. A control loop based on a single-cycle control principle and completed with a technique of control of the maximum current has been applied for the first time to a boost converter in order to eliminate the disturbances coming from the output of the photovoltaic cells. A first prototype with a single converter and with such a control loop has been successfully built and validated. Then a full system has been built which comprises: a DC-DC converter with its control loop for the 5 V-130 mA power supply and two parallel converters with their control loop for the 60 V output supply. This loop comprises an energy saving circuit which switches on the converters only when required by the health situation of the patient. It includes also a charge pump circuit which allows to supply the different 5 V control loop blocks using the 3.5 V input voltage. The entire system represents a 17.5 mm{sup 2} silicon surface. The second part of this work concerns the integration of a coil on a silicon surface. Iron/nickel alloy deposits on silicon substrates have been obtained and characterized. (J.S.)
Integrated power electronic converters and digital control
Emadi, Ali; Nie, Zhong
2009-01-01
Non-isolated DC-DC ConvertersBuck ConverterBoost ConverterBuck-Boost ConverterIsolated DC-DC ConvertersFlyback ConverterForward ConverterPush-Pull ConverterFull-Bridge ConverterHalf-Bridge ConverterPower Factor CorrectionConcept of PFCGeneral Classification of PFC CircuitsHigh Switching Frequency Topologies for PFCApplication of PFC in Advanced Motor DrivesIntegrated Switched-Mode Power ConvertersSwitched-Mode Power SuppliesThe Concept of Integrated ConverterDefinition of Integrated Switched-Mode Power Supplies (ISMPS)Boost-Type Integrated TopologiesGeneral Structure of Boost-Type Integrated T
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.
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 â€œThermal moduleâ€ 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.
Closed Loop Control of Soft Switched Interleaved Buck Converter
R. Shenbagalakshmi; Sree Renga Raja
2012-01-01
Design, Modeling and Simulation of a closed loop control is presented for Interleaved Buck Converter with Soft Switching. The features of the closed loop system are to reduce the switching losses and load current sharing among the parallel connected converters. The control system of the converter is designed using PWM technique. In order to improve the transient response and dynamic stability of the converters, the controller parameters are designed based on current mode control. Resonant com...
Directory of Open Access Journals (Sweden)
Cherif Larouci
2012-06-01
Full Text Available The current paper deals with a multi-objective design approach of power converters applied to a DC-DC buck structure. This approch consists on optimizing a preselected power architecture by minimizing a multi-objective function (volume and time response under multi-physic constraints (efficiency, thermal, electromagnetic compatibility and control. This multi-objective optimization allows evaluating the impact of the control aspect on the converter design by considering the control criteria with the same importance as the conventional constraints. The obtained results confirm the influence of the control on the converter design parameters. They help the designer to choose suitable operating points depending on the desired performances in terms of volume and time response while respecting efficiency, junction temperatures and electromagnetic compatibility constraints.
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; Blaabjerg, Frede
efficiency of above 97 % for the SiC JFET and over 90 % for the SI IGBT converter was measured. Cost differences between the two converters have been analyzed, showing that 772 days of operation are needed for the SiC converter costs to break even with the Si IGBT converter costs....
Methods of Battery Charging with Buck Converter Using Soft-Switching Techniques
Directory of Open Access Journals (Sweden)
S. Abinaya
2011-12-01
Full Text Available This paper is a detailed study on methods of battery charging with Buck Resonant converter using soft switching techniques like ZVS and ZCS. This study also presents the circuit configuration with the least components to realize a highly efficient solar energy battery charger with a zero-voltage and zero current switching resonant converter. The high-frequency resonant converter has numerous well-known advantages over the traditional hard-switching converters. The most important advantage is that it offers a lower switching loss and a higher power density. Additionally, the soft switching current waveform characterizes a lower electromagnetic interference (EMI. The operating principles and design procedure of the proposed charger with both zero voltage and zero current are thoroughly analyzed. The optimal values of the resonant components are computed by applying the characteristic curve and electric functions derived from the circuit configuration. Finally, a simulation model is implemented for charger circuit designed for a 12-V 4-Ah lead acid battery using zero voltage and zero current switching and MATLAB/SIMULINK software is used as the simulation tool. The proposed dc?dc battery charger has a straightforward structure, low cost, easy control, and high efficiency. Satisfactory performance is obtained from the experimental results.
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. PMID:24844896
Bifurcation Control of Current-Mode Buck Converter via TDFC
International Nuclear Information System (INIS)
Considering the TDFC controlled current-mode Buck converter featuring periodicity we propose a Fourier-decomposition based method for the bifurcation analysis of this system, hence the theoretical range of control gain of TDFC is determined. In addition, the power-stage experiment circuit is built and the control part is realized in a digital controller. The experimental results show that either bifurcation or chaos in the current-mode Buck converter can be controlled into the expectant period-1 orbit rapidly. (general)
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 be regulated effectively. By using the second input capacitor and the high side switches as an inherent active clamping circuit, zerovoltage switching (ZVS) for the power MOSFETs on the primary side, and zero-current switching (ZCS) for the diodes on the secondary side are achieved respectively to improve the performance of the proposed PWM converter. The principle of operation is analyzed and some design considerations are discussed. Simulation results using PLECS are given to verify the proposed analysis and design. An experimental converter prototype has been designed, constructed and tested in the laboratory to verify the validity of the theoretical analysis and also demonstrate the converter’s performance over wide variations in input voltage.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius
2013-01-01
This paper presents a new zero-voltage-switching (ZVS) isolated dc-dc converter which combines a boost halfbridge (BHB) cell and a full-bridge (FB) cell, so that two different type of power sources, i.e. both current-fed and voltage-fed, can be coupled effectively by the proposed converter for various applications, such as fuel cell and super-capacitor hybrid energy system. By fully using two high frequency transformers and a shared leg of switches, number of the power devices and associated gate driver circuits can be reduced. With phase-shift control, the converter can achieve ZVS turn-on of active switches and zero-current switching (ZCS) turn-off of diodes. In this paper, derivation, analysis and design of the proposed converter are presented. Finally, a 25~50 V input, 300~400 V output prototype with a 600 W nominal power rating is built up and tested to demonstrate the effectiveness of the proposed converter topology.
Two phase interleaved buck converter for driving high power LEDs
Beczkowski, Szymon; Munk-Nielsen, Stig
2011-01-01
The goal of this paper is to evaluate an interleaved buck topology for driving high current light-emitting diodes. Low output capacitor value allows the use of non-electrolytic capacitors extending the lifetime of the converter. Converter is operated as a constant, regulated current source which increases luminous efficacy of LED compared to PWM dimmed system. Because of the low dynamic resistance of LEDs the duty cycle of the converter does not change greatly with controlled current. By sett...
Design of a Fully Integrated Three-Level Buck Converter
Y. Neelima*,
2014-01-01
Dynamic response of a converter plays an important role in many applications which change load in a rapid manner, especially in POL (Point of load) applicant ions. Here a new method for improving the dynamic response of a converter is presented. Here separate control schemes are implemented during steady state as well as transient load conditions. A three level buck converter topology with fast transient response is discussed here. This topology does not require a soft start u...
Directory of Open Access Journals (Sweden)
SRDIC, S.
2015-08-01
Full Text Available This paper presents a buck-boost converter which is modified to utilize new 600 V gallium nitride (GaN power semiconductor devices in an application requiring 1200 V devices. The presented buck-boost converter is used as a part of a dc/dc stage in an all-GaN photovoltaic (PV inverter and it provides a negative voltage for the 3-level neutral-point-clamped (NPC PWM inverter which is connected to the utility grid. Since in this application the transistor and the diode of the buck-boost converter need to block the sum of the PV string voltage (which is normally in the range from 150 to 350 V and the dc bus voltage (which is in the order of 400 V, the 1200 V devices or series connection of 600 V devices need to be employed. Currently, 1200 V GaN power semiconductor devices are not commercially available. Therefore, the standard buck-boost converter is modified to enable the use of 600 V GaN devices in this particular application. Based on the proposed converter topology, a PSpice simulation model and a 600 W converter prototype were developed. Both simulation and experimental results show successful operation of the converter.
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.; Maksimovic, Dragan; Sarban, Rahimullah
2014-01-01
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) based capacitive incremental actuator, which has the potential to be used in automotive (e.g., EVs), space and...
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; Andersen, Michael A. E.; Noreika, A.; Tarvydas, P.
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.; Andersen, M. A. E.; Noreika, A.; Tarvydas, P.
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...
A DC-DC conversion powering scheme for the CMS Phase-1 pixel upgrade
Feld, L.; Fleck, M.; Friedrichs, M.; Hensch, R.; Karpinski, W.; Klein, K.; Sammet, J.; Wlochal, M.
2013-02-01
The CMS pixel detector was designed for a nominal instantaneous LHC luminosity of 1?1034 cm-2s-1. During Phase-1 of the LHC upgrade, the instantaneous luminosity will be increased to about twice this value. To preserve the excellent performance of the pixel detector despite the increase in particle rates and track densities, the CMS Collaboration foresees the exchange of its pixel detector in the shutdown 2016/2017. The new pixel detector will be improved in many respects, and will comprise twice the number of readout channels. A powering scheme based on DC-DC conversion will be adopted, which will enable the provision of the required power with the present cable plant. 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 between DC-DC converters.
A High Step up DC-DC Converter with Coupled Inductor for AC AND DC Module Applications
Anand.S; Eranna
2014-01-01
The grid connected AC module is an alternative solution in photovoltaic (PV) generation systems. It combines a PV panel and a micro inverter connected to grid. A high step up converter is used because the input is about 15V to 40V for a single PV panel. The proposed converter employs a zeta converter and a coupled inductor without extreme duty ratios generally needed for coupled inductor to achieve high step up voltage conversion,the leakage inductor energy of the coupled induc...
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.
Thermal Modeling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Zygimantas; Zhang, Zhe
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 by numerical modeling techniques. Therefore, thermal design through thermal modeling and simulation is becoming an integral part of the design process as less expensive compared to the experimenta l cut - and - try approach. Here the investigation is performed using finite element method - based modeling , and also the potential of such analysis was demonstrated by real - world measurements and comparison of obtained results . Thermal modeling was accomplishe d using finite element anal ysis software COMSOL and thermo - imaging camera was used to measure the thermal field distribution. Also, the improved configuration of power converter was proposed
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)
Synchronous Buck converter with Output Impedance Correction Circuit
Svikovic, Vladimir; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; García Suárez, Oscar; Cobos Márquez, José Antonio
2012-01-01
This work is related to the improvement of the output impedance of the Buck converter by means of introducing an additional power path that virtually increases the output capacitance during transients. It is well known that in VRM applications, with wide load steps, voltage overshoots and undershoots may lead to undesired performance of the load. To solve this problem, high-bandwidth high-switching frequency power converters can be applied to reduce the transient time or a big output capacito...
Design of a Fully Integrated Three-Level Buck Converter
Directory of Open Access Journals (Sweden)
Y. Neelima*,
2014-08-01
Full Text Available Dynamic response of a converter plays an important role in many applications which change load in a rapid manner, especially in POL (Point of load applicant ions. Here a new method for improving the dynamic response of a converter is presented. Here separate control schemes are implemented during steady state as well as transient load conditions. A three level buck converter topology with fast transient response is discussed here. This topology does not require a soft start up circuitry for three level buck converters. Simulation model is done in Matlab/Simulink and the result shows a great improvement in dynamic response of the system. The 3-level converter enables smaller inductors (1 NH than a buck, while generating a wide range of output voltages compared to a 1/2 model capacitor converter. The test-chip prototype delivers up to 0.85 a load current while generating output voltages from 0.4 to 1.4 V from a 2.4 V input supply. It achieves 77% peak efficiency at power density of 0.1 W/mm and 63% efficiency at maximum power density of 0.3 W/mm.
Zhongjie, Guo; Longsheng, Wu; Youbao, Liu
2010-12-01
To improve the compensation for the inherent instability in a current mode converter, the adaptive slope compensation, giving attention to the problems of the traditional compensation on compensation accuracy, loading capability and turning jitter, is presented. Based on the analysis of current loop, by detecting the input and output voltage, converting the adaptive slope compensation current, the compensation of the current loop is optimized successfully. It can not only improve the compensation accuracy but also eliminate the over compensation, the turning jitter and the poor loading capability in the reported slope compensation. A power supply chip with adaptive slope compensation has been fabricated in a 0.35 ?m CMOS process. The measurement results show that the chip starts up and operates steadily with the constant current limit under conditions of 5 V input voltage, from 10% to 100% duty cycle.
Simpliï¬ed 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 DCâ€“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 efï¬ciency 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.
Digital Linear and Nonlinear Controllers for Buck Converter
Directory of Open Access Journals (Sweden)
Shyama M
2012-03-01
Full Text Available Both linear PID controllers and fuzzy controllers are designed and implemented for a buck converter. Comparison between the two controllers is made in the aspect of design, implementation and experimental results. Design of fuzzy controllers is based on heuristic knowledge of the converter and tuned using trial and error, while the design of linear PID and PI controllers is based on the frequency response of the buck converter. Implementation of linear controllers is quite straightforward, while implementation of fuzzy controllers has its unique issues. A comparison of experimental results indicates that the performance of the fuzzy controller is superior to that of the linear PID and PI controllers. The fuzzy controller is able to achieve faster transient response, has more stable steady-state response, and is more robust under different operating points.
A NEW GENERATION VLSI APPROACH FOR THE PWM CONTROL OF AN INTEGRATED FOUR-PORT DC-DC CONVERTER
Directory of Open Access Journals (Sweden)
SANGAMESH SAKRI
2012-12-01
Full Text Available In the recent years, the increase in the petroleum prices, the rapid run out tendency of fossil fuel reserves and their unavoidable harmful effects and political instabilities in the regions of energy sources have been accelerated the studies on the renewable energy systems. Although various renewable energy power generations are in practice today, the most popular is using photovoltaic (PV arrays and wind generators. Since PV and wind sources can meet the required demand but either source alone provides an intermittent supply and energy storage is needed to deliver a reliable supply. However these two sources complement each other. A combined plant (hybrid therefore has higher availability than either individual source and so needs less storage capacity. This paper proposes a novel converter topology that interfaces four power ports: two sources (PVand wind source, one bidirectional storage port, and one isolated load port. Power electronic converter is needed to interface and concurrently control multiple renewable energy sources with the load along with energy storage in stand-alone or grid-connected residential, commercial and automobile applications. The power electronic interface also contains some level of monitoring and control functionality to ensure that the distributed energy system can operate as required. In the proposed scheme, a unique VLSI chip called Digital Signal Controller (DSC is used to implement the controller operation which has the features of both microcontroller and digital signal processor (DSP. In this work, dsPIC30F2010 DSC chip is used to program the phase shift angles and generate the PWM pulses for the converter switches. The results of proposed system are recorded and analyzed. The experimental results have verified the proposed scheme of PWM control. The proposed topology and control is particularly relevant to battery-backed power systems having multiple renewable sources.
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.; Thomsen, Ole Cornelius
2012-01-01
The Dielectric Electro Active Polymer (DEAP) material is a very thin (~80 Î¼m) silicone elastomer film with a compliant metallic electrode layer on both sides. The DEAP is fundamentally a capacitor that is capable of very high strain. The property that the polymer changes its shape, as a result of...... flaps. With the DEAP based high power actuator, it is expected to make a reliable and light solution with superior controllability. The current DEAP technology requires high DC voltage in the range of kV to fully utilize the DEAP material as an actuator. In this paper we propose a flyback converter...
Directory of Open Access Journals (Sweden)
S. Ramya
2012-11-01
Full Text Available The objective of this paper is to propose amulti-input power converter for the hybrid system in order tosimplify the power system and reduce the cost. The proposedconverter interfaces two unidirectional input ports and abidirectional port for storage element in a unified structure. Italso utilizes four power switches that are controlled independentlywith four different duty ratios. The renewable power systemhybridizes PV and Wind as main source & Battery Power forbackup energy source. Three different power operation modes aredefined for the converter based on utilization state of the battery asfollows: 1 An operation type wherein power is delivered to loadfrom hybrid renewable energy sources; 2A single type whereinonly one renewable energy source supplies power to the load withbattery discharging; 3 An operation type wherein power isdelivered to load from renewable sources along with batterycharging. A simple and cost effective control with DC-DCconverter is used for maximum power point tracking (MPPT andhence maximum power is extracted from the source .Theintegration of the hybrid renewable power system is implementedand simulated using MATLAB/SIMULINK.
A 0.35Î¼m 50V CMOS Sliding-Mode Control IC for Buck Converters
DEFF Research Database (Denmark)
HÃ¸yerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.; Andreani, Pietro
2007-01-01
This paper presents a hysteretic (sliding mode) control IC for a buck DC/DC converter for use as an envelope tracking power supply to increase the efficiency of an RF power amplifier. The IC integrates a high-bandwidth error amplifier, a comparator with hysteresis, and a high-side driver for an...... external N-channel power MOSFET. The total control loop delay using the implemented IC is 35ns, this is shown to be a 30% reduction compared to a state-of-the-art discrete IC based solution. The presented results also show that it is viable to integrate a 100MHz operational amplifier on the same die as a...
A 0.35?m 50V CMOS Sliding-Mode Control IC for Buck Converters
DEFF Research Database (Denmark)
HØyerby, Mikkel Christian Wendelboe; Andersen, Michael Andreas E.
2007-01-01
This paper presents a hysteretic (sliding mode) control IC for a buck DC/DC converter for use as an envelope tracking power supply to increase the efficiency of an RF power amplifier. The IC integrates a high-bandwidth error amplifier, a comparator with hysteresis, and a high-side driver for an external N-channel power MOSFET. The total control loop delay using the implemented IC is 35ns, this is shown to be a 30% reduction compared to a state-of-the-art discrete IC based solution. The presented results also show that it is viable to integrate a 100MHz operational amplifier on the same die as a high-voltage MOSFET driver operating with slew rates in excess of 5V/ns. The IC is demonstrated in a tracking power supply with 30W output power and 3?s rise/fall time, running from a 40V input. The complete IC, including pads, takes up 4mm2 in a 0.35?m 50V CMOS process.
Characterization of an integrated buck converter using infrared thermography
Viviès, Noelle; Haussener, Marion; Welemane, Hélène; Trajin, Baptiste; Vidal, Paul-Etienne
2014-01-01
This study deals with new integrated systems for power electronics applications including wide-gap semiconductors. Integration of Silicon carbide (SiC) components provides for instance new perspectives with higher temperature operating points than conventional Silicon (Si) semiconductors. The present work intends to study an integrated buck converter composed of a Silicon IGBT (Insulated-Gate Bipolar Transistor) and a Silicon carbide diode. By means of in...
Stability Aspects in One-Cycle Controlled Buck Converters
GURBINA, M.; LASCU, D.
2014-01-01
The paper aims to investigate issues related to one cycle controlled buck converters stability, in the situation when the integration capacitor discharging is performed through a non-zero value resistor, as it happens in practice. It is known that in this case the exponential discharge makes capacitor voltage theoretically never reach zero. Under these conditions, instability phenomena are expected when the discharge time is short, that is at high duty cycles. The stability co...
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 proposed balancing system.
Stability Aspects in One-Cycle Controlled Buck Converters
Directory of Open Access Journals (Sweden)
GURBINA, M.
2014-02-01
Full Text Available The paper aims to investigate issues related to one cycle controlled buck converters stability, in the situation when the integration capacitor discharging is performed through a non-zero value resistor, as it happens in practice. It is known that in this case the exponential discharge makes capacitor voltage theoretically never reach zero. Under these conditions, instability phenomena are expected when the discharge time is short, that is at high duty cycles. The stability condition is analytically derived with respect to the control voltage. It is shown that instability occurs with period doubling leading to a half switching frequency subharmonic. Computer simulations confirm the validity of theoretical considerations.
Integrated design & control of a buck boost converter
Scientific Electronic Library Online (English)
Martin J. Pomar, Garcia; Julio E., Normey-Rico; Gloria, Gutierrez; César de, Prada.
2009-09-01
Full Text Available This paper presents the integrated design and control of a buck boost converter (BBC). In the proposed methodology the design tool provides simultaneously the controller tuning and BBC design parameters in such a way that some closed-loop pre-specified static and dynamic behavior is obtained. This a [...] pproach contrasts with the traditional methodology, where the design of BBC is performed without taking into account its dynamical behavior. An optimization procedure is used to obtain the electronic components of the BBC and the tuning parameters of the controller, minimizing an objective function that considers the set of performance specifications. Although the methodology can be applied to any converter and any control strategy, in this particular case an ideal BBC and a Sliding Model Control (SMC) strategy are used. Some simulation results show the advantages and principally the flexibility that can be obtained with this approach.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
This paper introduces a new zero-voltage-switching (ZVS) isolated DC-DC converter with two input ports which can be utilized in hybrid energy systems, for instance, in a fuel cell and super-capacitor system. By fully using two high frequency transformers, the proposed converter can effectively...... integrate a current-fed boost half-bridge (BHB) and a full-bridge (FB) into one equivalent circuit configuration which has dual-input ability and additionally it can reduce the number of the power devices. With the phase-shift control, it can achieve zero-voltage switching turn-on of active switches and...
Implementation of PV System with Two Inductor Buck Boost Converter
Directory of Open Access Journals (Sweden)
T.Jeevanandham, M.Raja
2015-03-01
Full Text Available The project proposes a new converter for photovoltaic system which is substantially high performance oriented. Furthermore, the lack of batteries replacement water pumping systems without the use of chemicals are responsible for the failure of such systems in isolated areas. The converter is designed to drive a three-phase induction motor directly from photovoltaic system. The majority of commercial systems use low-voltage (PV energy. The use of three-phase induction motor presents a suitable replacement of dc motor though by the use of dc motor we can directly drive by means of converter dc supply, but due to its lack of performance and reliability, we have opted for three phase induction motor. In the developed technique, there is no specialized personnel for operating and the system is based on a current-fed multi-resonant converter also maintaining these motors. Here, we make use of the TIBC topology such that they are found to be made of Buck Boost converter which will both stabilize and boost the output supply. Thus, the project will be a low cost high efficiency water supply duo for agricultural industry. Though solar energy based water supply system is being developed for the past 20 years, this project will be a phenomenal change and development of renewable energy that could be used in agricultural industry projects.
Directory of Open Access Journals (Sweden)
Lina Morales Laguado
2010-05-01
Full Text Available This document proposes analysing and designing two control strategies for permanent current DC-DC buck converter. These kinds of electronic devices convert a constant-voltage to a lower constant-voltage (nonlinearity characteristics being demonstra- ted. Two nonlinear control techniques are shown. The first is a conventional optimal proportional error and integral error (PI controller based on minimising integral of time per squared errors (ITSE criteria. A model of the plant at an operation point was thus obtained. The second one was fuzzy control where input and output sets were also defined by minimising ITSE criteria in the overall system and establishing inputs such as proportional error and integral error. Load was then varied to establish the system’s efficiency with both the aforementioned controllers. It must be borne in mind that such systems should not present super-voltage since this can cause damage. The parameters found in designing both controllers thus corresponded to analytical and descriptive methodology. Simulation results, the performance index mentioned above (ITSE and power consumption showed that the sys- tem’s response for the fuzzy control drew more power consumption than the optimal controller; otherwise, obtained ITSE was lar- ger for the optimal control than the fuzzy control. It is concluded that exploring these types of converter is applicable when using nonlinear control techniques and minimising the different performance indices.
Scientific Electronic Library Online (English)
Eliana, Arango; Carlos, Ramos-Paja; Carlos, Carrejo; Roberto, Giral; Andres, Saavedra-Montes.
2011-09-01
Full Text Available Este artículo propone un pre-amplificador basado en convertidores DC-DC conectados en paralelo para la reducción de armónicos inyectados a fuentes de potencia. Las principales características del pre-amplificador son la reducción del rizado de corriente de entrada en convertidores de potencia, incre [...] mentado además la eficiencia del sistema de conversión. Se describe el cálculo de las condiciones óptimas de operación del pre-amplificador, así como su modelado matemático y control para operar en las condiciones seleccionadas. Así mismo, se analiza el pre-amplificador con un convertidor elevador clásico, obteniendo una reducción significativa en el rizado de corriente inyectado a la fuente, así como un incremento en la eficiencia del sistema. Finalmente, los análisis teóricos se confirman a través de simulaciones circuitales y resultados experimentales. Abstract in english An efficient pre-amplifier based on interleaved DC-DC boost switching converters to mitigate high-frequency harmonics injection to power sources is proposed. The main features of the pre-amplifier are mitigate the ripple of power converters input-current and improving the efficiency of the whole pow [...] er conversion chain. The pre-amplifier optimal operating conditions are calculated, and the circuit is modeled and controlled to operate in such conditions. The pre-amplifier interacting with a classical single boost is analyzed, obtaining a strong reduction in the current ripple injected to the source, and also improving the efficiency of the initial conversion system. Finally, the theoretical analyses are confirmed by means of circuital PSIM simulations and experimental results.
International Nuclear Information System (INIS)
A 1500 mA, 10 MHz self-adaptive on-time (SOT) controlled buck DC—DC converter is presented. Both a low-cost ripple compensation scheme (RCS) and a self-adaptive on-time generator (SAOTG) are proposed to solve the system stability and frequency variation problem. Meanwhile a self-adaptive power transistor sizing (SAPTS) technique is used to optimize the efficiency especially with a heavy load. The circuit is implemented in a 2P4M 0.35 ?m CMOS process. A small external inductor of 0.47 ?H and a capacitor of 4.7 ?F are used to lower the cost of the converter and keep the output ripple to less than 10 mV. The measurement results show that the overshoot of the load transient response is 8 mV at 200 mA step and the dynamic voltage scaling (DVS) performance is a rise of 16 ?s/V and a fall of 20 ?s/V. With a SAPTS technique and PFM control, the efficiency is maintained at more than 81% for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%. (semiconductor integrated circuits)
Power decoupling method for single phase differential buck converter
DEFF Research Database (Denmark)
Yao, Wenli; Tang, Yi
2015-01-01
The well-known inherent second-order ripple power in single phase converters imposes harmonic stress on the dc link, resulting in low efficiency and overheating issues. In order to avoid installing bulky electrolytic capacitors or LC filters in the dc-link, this paper presents a differential buck inverter to improve the dc link power quality, and an improved active power decoupling method is proposed to achieve ripple power reduction for both AC-DC and DC-AC conversions. The ripple energy storage is realized by the filter capacitors, which are connected between the output terminal and the negative dc bus. By properly controlling the differential mode voltage of the capacitors, it is possible to transfer desired energy between the DC port and AC port. The common mode voltage is controlled in such a way that the ripple power on the dc side will be reduced. Furthermore, an autonomous reference generation technique is proposed to provide accurate ripple power compensation, and closed-loop controllers are also designed based on small signal models. The effectiveness of this power decoupling method is verified by detailed simulation studies as well as laboratory prototype experimental results.
Mclyman, C. W.
1983-01-01
Compact dc/dc inverter uses single integrated-circuit package containing six inverter gates that generate and amplify 100-kHz square-wave switching signal. Square-wave switching inverts 10-volt local power to isolated voltage at another desired level. Relatively high operating frequency reduces size of filter capacitors required, resulting in small package unit.
Buck-Buck- Boost Regulatr (B3R)
Mourra, Olivier; Fernandez, Arturo; Landstroem, Sven; Tonicello, Ferdinando
2011-10-01
In a satellite, the main function of a Power Conditioning Unit (PCU) is to manage the energy coming from several power sources (usually solar arrays and battery) and to deliver it continuously to the users in an appropriate form during the overall mission. The objective of this paper is to present an electronic switching DC-DC converter called Buck-Buck-Boost Regulator (B3R) that could be used as a modular and recurrent solution in a PCU for regulated or un- regulated 28Vsatellite power bus classes. The power conversion stages of the B3R topology are first described. Then theoretical equations and practical tests illustrate how the converter operates in term of power conversion, control loops performances and efficiency. The paper finally provides some examples of single point failure tolerant implementation using the B3R.
Design Considerations for High Step-Down ratio Buck Regulators
Khanna, R
2008-01-01
The buck or step-down DC-DC converter is the workhorse switching power supply topology. It utilizes two switches (two FETS or one FET and one diode) along with an output inductor and output capacitor. Whether you look at a large computer server, a personal desktop or a laptop computer, a cell phone or a GPS unit all will contain a buck converter in one form or another. This paper will discuss the synchronous buck topology, design considerations, component selection followed by a small signal model of buck converter. Issues that are important in optimizing the efficiency of the design for example MOSFET selection, the impact that the MOSFET driver plays in improving the efficiency will be examined. The paper will finish by contrasting various control architectures.
Mechouma Rabiaa; Azoui Boubekeur
2014-01-01
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...
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius
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 integrate a current-fed boost half-bridge (BHB) and a full-bridge (FB) into one equivalent circuit configuration which has dual-input ability and additionally it can reduce the number of the power devices. With the phase-shift control, it can achieve zero-voltage switching turn-on of active switches and zero-current switching (ZCS) turn-off of diodes leading to negligible reverse recovery loss. Voltage conversion ratio is higher compared to the conventional boost converter owing to the BHB circuit and the corresponding control. Finally, a 25~50 V input, 300~400 V output prototype with a 600 W nominal power rating are built up and tested to demonstrate the effectiveness of the proposed converter topology.
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.
Application of Theory of Hybrid Systems to Control the Switching of Buck Converter
Benmiloud, Mohammed
2013-08-01
The field of power electronics poses challenging control problems that canâ€™t be treated in a complete manner using traditional modeling. In this paper, the buck converter operating in Continuous Conduction Mode (CCM) is represented analytically by hybrid automaton model and graphically representation is also given. The hybrid trajectory and the model behavior are presented. The control problem of buck switching converters is transformed to a guard selection problem. The guard selection calculation formulas of buck converter are derived from the basic circuit laws. The stability of the switching is established analytically by the use of multiple Lyapunov functions to ensure the convergence and Poincare map to assess the local stability of the limit cycle. Numerical results clearly bring out the advantages and effectiveness of the proposed control law under varying line voltage and load conditions. Simulation studies are carried out in Matlab/Simulink/Stateflow.
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...
Simulation and Implementation a Non-Isolated Buck Converter at ZCS Condition
Directory of Open Access Journals (Sweden)
Nahid Hematian
2013-10-01
Full Text Available A new soft-switching resonant inverting-buck converter with high efficiency is presented. The proposed converter steps down and inverts the input voltage. The zero-current-switching (ZCS technique is employed to reduce switching losses and Electromagnetic Interferences (EMI. An LLC resonant network is utilized to provide soft-switching conditions for all semiconductor devices. Experimental results verify the integrity of the proposed converter operation and the presented theoretical analysis.
Cheng, Pengming; Vasic, Miroslav; García Suárez, Oscar; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; Cobos Márquez, José Antonio
2011-01-01
This paper proposes an interleaved multiphase buck converter with minimum time control strategy for envelope amplifiers in high efficiency RF power amplifiers. The solution of the envelope amplifier is to combine the proposed converter with a linear regulator in series. High system efficiency can be obtained through modulating the supply voltage of the envelope amplifier with the fast output voltage variation of the converter working with several particular duty cycles that achieve tot...
International Nuclear Information System (INIS)
Based on the fact that the real inductor and the real capacitor are fractional order in nature and the fractional calculus, the transfer function modeling and analysis of the open-loop Buck converter in a continuous conduction mode (CCM) operation are carried out in this paper. The fractional order small signal model and the corresponding equivalent circuit of the open-loop Buck converter in a CCM operation are presented. The transfer functions from the input voltage to the output voltage, from the input voltage to the inductor current, from the duty cycle to the output voltage, from the duty cycle to the inductor current, and the output impedance of the open-loop Buck converter in CCM operation are derived, and their bode diagrams and step responses are calculated, respectively. It is found that all the derived fractional order transfer functions of the system are influenced by the fractional orders of the inductor and the capacitor. Finally, the realization of the fractional order inductor and the fractional order capacitor is designed, and the corresponding PSIM circuit simulation results of the open-loop Buck converter in CCM operation are given to confirm the correctness of the derivations and the theoretical analysis
Design and realization of the BUCK converter based on anti-saturated PI controller
Directory of Open Access Journals (Sweden)
JIANG Lan
2013-02-01
Full Text Available A kind of anti-saturated digital PI regulator is designed and implemented based on DSP.This PI regulator was applied to the system design of voltage and current double-loop control in a BUCK converter and related experimental research was made in a 5.5 KW prototype machine.Experimental results show that the converter has good static and dynamic performances and the validity of the design of the PI regulator is verified.
Space-state robust control of a Buck converter with amorphous core coil and variable load
Morales Cabrera, Rafael; Somolinos Sanchez, Jose Andres; Moron Fernandez, Carlos; Garcia Garcia, Alfonso
2013-01-01
Pulse-width modulation is widely used to control electronic converters. One of the most frequently used topologies for high DC voltage/low DC voltage conversion is the Buck converter. These converters are described by a second order system with an LC filter between the switching subsystem and the load. The use of a coil with an amorphous magnetic material core rather than an air core permits the design of smaller converters. If high switching frequencies are used to obtain high quality voltag...
Cheng, Pengming; Vasic, Miroslav; García Suárez, Oscar; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; Cobos Márquez, José Antonio
2011-01-01
In this paper, an interleaved multiphase buck converter with minimum time control strategy for envelope amplifiers in high efficiency RF power amplifiers is proposed. The solution for the envelope amplifier is to combine the proposed converter with a linear regulator in series. High efficiency of envelope amplifier can be obtained through modulating the supply voltage of the linear regulator. Instead of tracking the envelope, the buck converter has discrete output voltage that corresponding t...
Energy Technology Data Exchange (ETDEWEB)
Lee, H. [Kyungnam University (Korea, Republic of)
1996-10-27
A soft switching method with small switching loss was proposed for the purpose of increasing the efficiency of a DC-DC boost converter which converted a DC current generated by solar cells to a variable DC current. Existing current converters are supplemented by using a snubber circuit around the switch so as to protect the switch by a hard switching action. However, with an increase of the output current, snubber loss is increased, reducing the efficiency. In order to solve this problem, the partial resonant switch method was applied to the converter; with this method of partially forming a resonant circuit only at the time of turning on/off of the switch, the switching loss was reduced through the soft switching, thereby making the proposed converter operate with high efficiency. Moreover, the resonant element of the partial resonant circuit using a snubber condenser, the energy accumulated in the condenser was regenerated on the power supply side without loss of snubber. With the regenerated energy, the proposed converter was provided with a smaller ratio of switching to use than the conventional converter. 4 refs., 7 figs., 1 tab.
Energy Technology Data Exchange (ETDEWEB)
Amjadi, Zahra; Williamson, Sheldon
2010-09-15
This paper presents the analysis and novel hybrid controller design for an interleaved 2-quadrant switched capacitor (SC) bidirectional DC/DC converter for a hybrid electric vehicle (HEV) dual energy storage system. The designed novel control strategy enables simpler dynamics compared to a standard buck converter with input filter, good regulation capability, low EMI, lower source current ripple, ease of control, and continuous input current waveform in both buck as well as boost modes of operation.
Modelling and Simulation of Closed Loop Controlled Buck Converter Fed Pmbldc Drive System
Directory of Open Access Journals (Sweden)
R. Dhanasekaran
2011-04-01
Full Text Available Permanent Magnet Brushless DC Motor (PMBLDC is one of the best electrical drives that has increasing popularity, due to their high efficiency, reliability, good dynamic response and very low maintenance. This makes the interest of modeling an ideal PMBLDC motor and itâ€™s associated Drive System in simple and lucid manner. In this paper the drive system is proposed with a buck converter topology. It has the advantages of reduced switching losses, low inductor power loss, reduced ripple by using a pi-filter, which in turn makes the DC link voltage to be stable. The modeling and simulation of the PMBLDC motor is done using the software package MATLAB/SIMULINK. The operation principle of the buck converter is analyzed and the simulation results are presented in this paper to verify the theoretical analysis.
Non-Inverted Buck-Boost Converters with Dual Delta Sigma Modulators
Kobori, Yasunori; Kono, Masashi; Shimizu, Toshihiko; Kobayashi, Haruo
This paper presents a new control circuit to create high-performance non-inverted Buck-Boost converter with dual ⊿âˆ‘ modulations. Experimental load regulation, corresponding to load current steps of Â±0.5A, is within 45mVpp, and the efficiency without synchronized rectifier is 83% at input voltage 2.5V and load current 0.8A.
Filter based non-invasive control of chaos in Buck converter
International Nuclear Information System (INIS)
A non-invasive method for controlling chaos in the voltage-mode Buck converter is proposed by using a hybrid active filter based feedback controller in this Letter. The harmonic balance method is applied to obtaining the bifurcation-point equations of the controlled system. Hence, a stability-boundary diagram is constructed, through which the control parameters are chosen correctly. The results of simulation and experiment are given after all
A New Buck-Boost Converter for a Hybrid-Electric Drive Stand
Directory of Open Access Journals (Sweden)
P. Mašek
2009-01-01
Full Text Available This paper describes work on the laboratory working stand for a hybrid-electric drive located in laboratory T2:H1-26.The basic idea is to operate the combustion engine in its optimal regime. In this regime the engine has the highest efficiency and minimal smoke exhaust. This optimal regime is only a small portion of its operation area. Because the engine has to operate in this area, it is necessary to add a new converter to the hybrid-electric stand. The new converter must be allowed to buck and boost and must operate as a current source in this regime.
Evaluation of Arm Processor-based Bionic Intelligent Controller for a Buck-boost Converte
Directory of Open Access Journals (Sweden)
M.V. Mini
2015-07-01
Full Text Available This study focuses on performance-comparison of different tuning methods for a PI controller applied to a buck-boost converter. Comparison between the controllers is made by analysis of design methodology implementation issues and empirically measured performance. Design of PI controller is based on frequency response of the converter. The optimization of PI controller is based on ant colony algorithm. Experimental results show that, tuning the PI controller using ACO algorithm gave better performance than the conventional algorithm. This is mainly due to the fact ACO is capable of reducing the overshoot without oscillation.
Active pre-filters for dc/dc Boost regulators
Directory of Open Access Journals (Sweden)
Carlos Andrés Ramos-Paja
2014-07-01
Full Text Available This paper proposes an active pre-filter to mitigate the current harmonics generated by classical dc/dc Boost regulators, which generate current ripples proportional to the duty cycle. Therefore, high output voltage conditions, i.e., high voltage conversion ratios, produce high current harmonics that must be filtered to avoid damage or source losses. Traditionally, these current components are filtered using electrolytic capacitors, which introduce reliability problems because of their high failure rate. The solution introduced in this paper instead uses a dc/dc converter based on the parallel connection of the Boost canonical cells to filter the current ripples generated by the Boost regulator, improving the system reliability. This solution provides the additional benefits of improving the overall efficiency and the voltage conversion ratio. Finally, the solution is validated with simulations and experimental results.
Dynamics and stabilization of peak current-mode controlled buck converter with constant current load
Leng, Min-Rui; Zhou, Guo-Hua; Zhang, Kai-Tun; Li, Zhen-Hua
2015-10-01
The discrete iterative map model of peak current-mode controlled buck converter with constant current load (CCL), containing the output voltage feedback and ramp compensation, is established in this paper. Based on this model the complex dynamics of this converter is investigated by analyzing bifurcation diagrams and the Lyapunov exponent spectrum. The effects of ramp compensation and output voltage feedback on the stability of the converter are investigated. Experimental results verify the simulation and theoretical analysis. The stability boundary and chaos boundary are obtained under the theoretical conditions of period-doubling bifurcation and border collision. It is found that there are four operation regions in the peak current-mode controlled buck converter with CCL due to period-doubling bifurcation and border-collision bifurcation. Research results indicate that ramp compensation can extend the stable operation range and transfer the operating mode, and output voltage feedback can eventually eliminate the coexisting fast-slow scale instability. Project supported by the National Natural Science Foundation of China (Grant No. 61371033), the Fok Ying-Tung Education Foundation for Young Teachers in the Higher Education Institutions of China (Grant No. 142027), the Sichuan Provincial Youth Science and Technology Fund, China (Grant Nos. 2014JQ0015 and 2013JQ0033), and the Fundamental Research Funds for the Central Universities, China (Grant No. SWJTU11CX029).
Bifurcations and chaos produced by the modulation signal in a PWM buck converter
International Nuclear Information System (INIS)
We present an analysis of the complex dynamics displayed by the classical buck converter, controlled with a Pulse-Width-Modulation technique. We show the conditions to make the circuit display a sliding mode and a null steady-state error. Also, some conditions for the existence of a periodic orbit with the same period as the modulation signal are established. Finally, taking the period of the modulation signal as a bifurcation parameter, we describe a situation where the controlled circuit exhibits chaotic behavior.
Sensorless load torque estimation and passivity based control of buck converter fed DC motor.
Kumar, S Ganesh; Thilagar, S Hosimin
2015-01-01
Passivity based control of DC motor in sensorless configuration is proposed in this paper. Exact tracking error dynamics passive output feedback control is used for stabilizing the speed of Buck converter fed DC motor under various load torques such as constant type, fan type, propeller type, and unknown load torques. Under load conditions, sensorless online algebraic approach is proposed, and it is compared with sensorless reduced order observer approach. The former produces better response in estimating the load torque. Sensitivity analysis is also performed to select the appropriate control variables. Simulation and experimental results fully confirm the superiority of the proposed approach suggested in this paper. PMID:25893208
ANALYSIS OF VARIABLE SPEED PFC BUCK–BOOST CONVERTER-FED PMBLDC MOTOR DRIVE
Directory of Open Access Journals (Sweden)
K. Raghavareddy
2015-09-01
Full Text Available This paper presents an analysis of variable speed low power drive with PFC at supply ends by using BLDC PM motor fed from buck-boost converter. The speed control of BLDC achieved by simply control the DC link voltage of VSI converter which is taken as reference signal. This facilitates the operation of VSI at fundamental frequency switching by using the electronic commutation of the BLDC motor which offers reduced switching losses. A PFC buck–boost converter is designed to operate in discontinuous inductor current mode (DICM to provide an inherent PFC at ac mains. The performance of the proposed drive is evaluated over a wide range of speed control and varying supply voltages (universal ac mains at 170–270 V with improved power quality at ac mains. The obtained power quality indices are within the acceptable limits of international power quality standards such as the IEC 61000-3-2. The performance of the proposed drive is simulated in MATLAB/Simulink environment, and the obtained results are validated experimentally on a developed prototype of the drive.
Reduce Energy Losses and THD in Buck Converter Using Control Algorithm
Directory of Open Access Journals (Sweden)
Vipul C. Rajyaguru, Keerti S.Vashishtha, K. C. Dave
2012-04-01
Full Text Available The paper will focus on modeling, analysis, and design and simulation buck converter architecture. This architecture is used for automotive dual power system to reduce filters, dynamic response and power. The converter is designed in CCM (continuous conduction mode. The voltage mode control strategy is proposed by using pulse width modulation (PWM with a proportional-integralderivative (PID. The effectiveness of the step down converter is verified through simulation results using control oriented simulator like MATLAB/Simulink tools.The proposed circuits operate at constant frequency and are regulated by conventional pulse width modulation (PWM using dedicated PWM and PID control techniques. The circuit operation, mathematical analysis, designs and simulation results for continuous current mode (CCM operation are mentioned in this paper.
Design Of Converter For Low Power Photovoltaic Conversion System
Directory of Open Access Journals (Sweden)
SWAPNIL ZADEY, SUBROTO DUTT
2013-06-01
Full Text Available The solar energy conversion system is an alternative for conventional power generating system. It has no running cost due to freely available and non polluting solar radiations. The voltage which is available from solar array is variable and to obtain a stable voltage from solar panels, DC-DC converters are required for constant power production. There are mainly three converters namely Buck, Boost and Buck-Boost converters which can be used for either increasing or decreasing the voltage. This paper presents mobile charging circuit with a PV source. The circuit structure of the proposed system adopts buck converter combined PWM MPPT technique. In this research, buck converter is used as a charger for charging mobile battery. The input voltage can typically change from (12V initially, down to (5V, and provide a regulated voltage within the range of the 4.5V required for the charging of mobile batteries.
Electrodeposited Nanolaminated CoNiFe Cores for Ultracompact DC-DC Power Conversion
Energy Technology Data Exchange (ETDEWEB)
Kim, J; Kim, M; Herrault, F; Park, JY; Allen, MG
2015-09-01
Laminated metallic alloy cores (i.e., alternating layers of thin film metallic alloy and insulating material) of appropriate lamination thickness enable suppression of eddy current losses at high frequencies. Magnetic cores comprised of many such laminations yield substantial overall magnetic volume, thereby enabling high-power operation. Previously, we reported nanolaminated permalloy (Ni-80 Fe-20) cores based on a sequential electrodeposition technique, demonstrating negligible eddy current losses at peak flux densities up to 0.5 T and operating at megahertz frequencies. This paper demonstrates improved performance of nanolaminated cores comprising tens to hundreds of layers of 300-500-nm-thick CoNiFe films that exhibit superior magnetic properties (e.g., higher saturation flux density and lower coercivity) than permalloy. Nanolaminated CoNiFe cores can be operated up to a peak flux density of 0.9 T, demonstrating improved power handling capacity and exhibiting 30% reduced volumetric core loss, attributed to lowered hysteresis losses compared to the nanolaminated permalloy core of the same geometry. Operating these cores in a buck dc-dc power converter at a switching frequency of 1 MHz, the nanolaminated CoNiFe cores achieved a conversion efficiency exceeding 90% at output power levels up to 7 W, compared to an achieved permalloy core conversion efficiency below 86% at 6 W.
Directory of Open Access Journals (Sweden)
M.S.SIVAGAMAUNDARI, DR.P.MELBA MARY, V.K.VELVIZHI
2013-06-01
Full Text Available Energy, especially alternative source of energy is vital for the development of a country. In future, the world anticipates to develop more of its solar resource potential as an alternative energy source to overcome the persistent shortages and unreliability of power supply. In order to maximize the power output the system components of the photovoltaic system should be optimized. For the optimization maximum power point tracking (MPPT is a promising technique that grid tie inverters, solar battery chargers and similar devices use to get the maximum possible power from one or more solar panels. Among the different methods used to track the maximum power point, Perturb and Observe method is a type of strategy to optimize the power output of an array. In this method, the controller adjusts the voltage by a small amount from the array and measures power, if the power increases, further adjustments in that direction are tried until power no longer increases. In this research paper the system performance is optimized by perturb and observe method using buck boost converter. By varying the duty cycle of the buck boost converter, the source impedance can be matched to adjust the load impedance to improve the efficiency of the system. The Performance has been studied by the MATLAB/Simulink.
A 10 MHz ripple-based on-time controlled buck converter with dual ripple compensation
International Nuclear Information System (INIS)
A 10 MHz ripple-based on-time controlled buck converter is presented. A novel low-cost dual ripple compensation, which consists of coupling capacitor compensation and passive equivalent series resistance compensation, is proposed to achieve a fast load transient response and robust stability simultaneously. Implemented in a 2P4M 0.35 ?m CMOS process, the converter achieves fix-frequency output with a ripple of below 10 mV and an overshoot of 10 mV at 400 mA step load transient response. With width optimization of the power transistors in an ultra-heavy load and PFM control in a light load, the efficiency stays at over 83% for a load range from 20 mA to 1.5 A and the peak efficiency reaches 90.16%. (semiconductor integrated circuits)
Svikovic, Vladimir; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; García Suárez, Oscar; Cobos Márquez, José Antonio
2012-01-01
This work is related to the improvement of the dynamic performance of the Buck converter by means of introducing an additional power path that virtually increase s the output capacitance during transients, thus improving the output impedance of the converter. It is well known that in VRM applications, with wide load steps, voltage overshoots and undershoots ma y lead to undesired performance of the load. To solve this problem, high-bandwidth high-switching frequency power converter s can be a...
Bradley, Mark; Alarcón Cot, Eduardo José; Feely, Orla
2014-01-01
Digital control of switching power converters is an area which has seen increased attention in recent years. However, quantization in the feedback loop from the analog-to-digital (A/D) converter and the digital pulse width modulator (DPWM) may cause limit cycle oscillations to manifest, which are generally seen as being undesirable. This paper presents an analysis of the limit cycle behavior found in a multiple-sampled digitally controlled buck converter. The limit cycles which may arise in t...
International Nuclear Information System (INIS)
An analog implementation of a novel fixed-frequency quasi-sliding-mode controller for single-inductor dual-output (SIDO) buck converter in pseudo-continuous conduction mode (PCCM) with a self-adaptive freewheeling current level (SFCL) is presented. Both small and large signal variations around the operation point are considered to achieve better transient response so as to reduce the cross-regulation of this SIDO buck converter. Moreover, an internal integral loop is added to suppress the steady-state regulation error introduced by conventional PWM-based sliding mode controllers. Instead of keeping it as a constant value, the free-wheeling current level varies according to the load condition to maintain high power efficiency and less cross-regulation at the same time. To verify the feasibility of the proposed controller, an SIDO buck converter with two regulated output voltages, 1.8 V and 3.3 V, is designed and fabricated in HEJIAN 0.35 ?m CMOS process. Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 ?s while the cross-regulation is reduced to 0.057 mV/mA, when its first load changes from 50 to 100 mA. (semiconductor integrated circuits)
Sampled-Data and Harmonic Balance Analyses of Average Current-Mode Controlled Buck Converter
Fang, Chung-Chieh
2012-01-01
Dynamics and stability of average current-mode control of buck converters are analyzed by sampled-data and harmonic balance analyses. An exact sampled-data model is derived. A new continuous-time model "lifted" from the sampled-data model is also derived, and has frequency response matched with experimental data reported previously. Orbital stability is studied and it is found unrelated to the ripple size of the current-loop compensator output. An unstable window of the current-loop compensator pole is found by simulations, and it can be accurately predicted by sampled-data and harmonic balance analyses. A new S plot accurately predicting the subharmonic oscillation is proposed. The S plot assists pole assignment and shows the required ramp slope to avoid instability.
Yahaya, N.Z; Lee, M. K.; Begam, K. M.; Awan, M.
2010-01-01
This work is about the analysis of dead time variation on switching losses in a Zero Voltage Switching (ZVS) synchronous buck converter (SBC) circuit. In high frequency converter circuits, switching losses are commonly linked with high and low side switches of SBC circuit. They are activated externally by the gate driver circuit. The duty ratio, dead time and resonant inductor are the parameters that affect the efficiency of the circuit. These variables can be adjusted for the optimization pu...
The DC-DC conversion power system of the CMS Phase-1 pixel upgrade
Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Preuten, M.; Rauch, M.; Schmitz, St.; Wlochal, M.
2015-01-01
The pixel detector of the CMS experiment will be exchanged during the year-end technical stop in 2016/2017, as part of the experiment's Phase-1 upgrade. The new device will feature approximately twice the number of readout channels, and consequently the power consumption will be doubled. By moving to a DC-DC conversion powering scheme, it is possible to power the new pixel detector with the existing power supplies and cable plant. The power system of the Phase-1 pixel detector is described and the performance of the new components, including DC-DC converters, DC-DC converter motherboards and various power distribution boards, is detailed. The outcome of system tests in terms of electrical behaviour, thermal management and pixel module performance is discussed.
The DC-DC conversion power system of the CMS Phase-1 pixel upgrade
International Nuclear Information System (INIS)
The pixel detector of the CMS experiment will be exchanged during the year-end technical stop in 2016/2017, as part of the experiment's Phase-1 upgrade. The new device will feature approximately twice the number of readout channels, and consequently the power consumption will be doubled. By moving to a DC-DC conversion powering scheme, it is possible to power the new pixel detector with the existing power supplies and cable plant. The power system of the Phase-1 pixel detector is described and the performance of the new components, including DC-DC converters, DC-DC converter motherboards and various power distribution boards, is detailed. The outcome of system tests in terms of electrical behaviour, thermal management and pixel module performance is discussed
Scientific Electronic Library Online (English)
C. A, Ramos-Paja; R, Giral; C, Carrejo.
2014-08-01
Full Text Available Este artículo propone un pre-filtro activo para mitigar los armónicos de corriente generados por reguladores elevadores clásicos, los cuales producen rizados de corriente proporcionales al ciclo de trabajo. Por tanto, altos voltajes de salida, i.e., altos factores de transformación de voltaje, produ [...] cen armónicos de corriente que se deben filtrar para evitar daños o pérdidas de potencia en la fuente. Tradicionalmente, estas componentes se filtran usando condensadores electrolíticos, lo que introducen problemas de confiabilidad debido a su alta taza de falla. En contraste, la solución propuesta usa un convertidor dc/dc, basado en la conexión paralela de celdas canónicas Boost, para filtrar el rizado de corriente generado por el regulador Boost, lo que mejora la confiabilidad del sistema. Esta solución, además, incrementa la eficiencia total y el factor de transformación de voltaje. Finalmente, la solución se valida usando simulaciones y resultados experimentales. Abstract in english This paper proposes an active pre-filter to mitigate the current harmonics generated by classical dc/dc Boost regulators, which generate current ripples proportional to the duty cycle. Therefore, high output voltage conditions, i.e., high voltage conversion ratios, produce high current harmonics tha [...] t must be filtered to avoid damage or source losses. Traditionally, these current components are filtered using electrolytic capacitors, which introduce reliability problems because of their high failure rate. The solution introduced in this paper instead uses a dc/dc converter based on the parallel connection of the Boost canonical cells to filter the current ripples generated by the Boost regulator, improving the system reliability. This solution provides the additional benefits of improving the overall efficiency and the voltage conversion ratio. Finally, the solution is validated with simulations and experimental results.
Design And Implementation Of Luo Converter For Electric Vehicle Applications
Directory of Open Access Journals (Sweden)
A.Manikandan
2013-10-01
Full Text Available This paper proposes the stable and ripple free output voltage from the design of developed Dc-Dc converter topology. Dc voltage provided by battery contains high voltage ripples and it is not constant enough voltage, thus it is not applicable for most devices like electric-vehicle controller, dc-chargers, etc. Dc-Dc converters are employed to attenuate the ripples regardless of change in the load voltage. In the existing method, the classical buck converter for electric vehicle applications does not meet the load requirement containing more ripples on the output voltage and parasitic effects. To overcome this problem the advanced developed Dc-Dc luo-converter technology was introduced. luo converter is the developed converter derived from the buck-boost converter. In this proposed model the additional filter elements in the luo-converter eliminate the output ripples and effectively enhance the output voltage level. A computer simulation using MATLAB/SIMULINK confirms the predicted results.
A High Step-Down Interleaved Buck Converter with Active-Clamp Circuits for Wind Turbines
Directory of Open Access Journals (Sweden)
Chih-Lung Shen
2012-12-01
Full Text Available In this paper, a high step-down interleaved buck coupled-inductor converter (IBCC with active-clamp circuits for wind energy conversion has been studied. In high step-down voltage applications, an IBCC can extend duty ratio and reduce voltage stresses on active switches. In order to reduce switching losses of active switches to improve conversion efficiency, a IBCC with soft-switching techniques is usually required. Compared with passive-clamp circuits, the IBCC with active-clamp circuits have lower switching losses and minimum ringing voltage of the active switches. Thus, the proposed IBCC with active-clamp circuits for wind energy conversion can significantly increase conversion efficiency. Finally, a 240 W prototype of the proposed IBCC with active-clamp circuits was built and implemented. Experimental results have shown that efficiency can reach as high as 91%. The proposed IBCC with active-clamp circuits is presented in high step-down voltage applications to verify the performance and the feasibility for energy conversion of wind turbines.
A novel DC-DC convertor using LTCC technology for magnetic integration application
International Nuclear Information System (INIS)
A compact DC-DC convertor is proposed and fabricated in multilayer ferrite substrate using LTCC technology. The spiral conductors are buried into the ferrite substrate with a multilayer 3-D structure to reduce the volume of convertor. The passive integration of magnetic components and surface circuitry are achieved in a whole substrate and the size of module can be reduced markedly. The whole height of module is only 3mm, 1/3 of the height of conventional modules. Testing results indicate that the performance of the module is excellent in Point-of-Load (POL) field. The step-down DC-DC converter converts input voltage of 5V to output voltage of 3.3V. It is confirmed that the maximum conversion efficiency of 93.2% is sufficient for actual DC-DC converter application. Such a compact DC-DC convertor provides a compact, low cost and high reliability approach for power supply and magnetic integration application.
A novel DC-DC convertor using LTCC technology for magnetic integration application
Energy Technology Data Exchange (ETDEWEB)
Xu, Z Q [Research Institutes, University of Electronic Science and Technology of China, Chengdu (China); Shi, Y; Guo, H P; Yang, B C, E-mail: nanterxu@uestc.edu.cn [State key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu (China)
2011-01-01
A compact DC-DC convertor is proposed and fabricated in multilayer ferrite substrate using LTCC technology. The spiral conductors are buried into the ferrite substrate with a multilayer 3-D structure to reduce the volume of convertor. The passive integration of magnetic components and surface circuitry are achieved in a whole substrate and the size of module can be reduced markedly. The whole height of module is only 3mm, 1/3 of the height of conventional modules. Testing results indicate that the performance of the module is excellent in Point-of-Load (POL) field. The step-down DC-DC converter converts input voltage of 5V to output voltage of 3.3V. It is confirmed that the maximum conversion efficiency of 93.2% is sufficient for actual DC-DC converter application. Such a compact DC-DC convertor provides a compact, low cost and high reliability approach for power supply and magnetic integration application.
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Ouyang, Ziwei; Andersen, Michael A. E.; Thomsen, Ole Cornelius
In this paper an analysis of two planar transformers designed for high-current switching applications is presented. Typical converter application is represented by fuel and electrolyser cell converters. The transformer designs are based on E+I and ER+I planar cores while the analysis focuses on...
Energy Technology Data Exchange (ETDEWEB)
Lopez, Henrique Fioravanti Miguel
2009-08-15
This work presents the study and development of a processing power system that could be used in the connection of renewable energy sources to commercial power grid. The system consists of a ZETA converter associated with a bridge inverter operating at low frequency. The Zeta converter, operating in discontinuous conduction mode (DCM), plays the main role in this arrangement, producing a rectified sinusoidal current waveform synchronized with the electric grid. The function of the full-bridge inverter, connected in cascade with the Zeta converter, is to reverse every 180 deg the current generated by the Zeta converter. Initially it presents the analysis of the Zeta converter operating in DCM, as well as a design criterion. Following by the control strategy and the experimental results for the proposed system are presented and discussed. (author)
Energy Technology Data Exchange (ETDEWEB)
Schoenen, Timo
2011-07-01
Every time a new hybrid or electrical vehicle is developed, different topologies are compared to achieve the best results regarding weight costs and efficiency. The integration of a dc-to-dc converter between the battery stack and the power train is a frequently discussed alternative because the preferred voltage of the inverter and machine are often higher than the voltage of the battery stack. Within this thesis this approach was studied in detail and compared with the conventional concept without using a dc-to-dc converter. Therefore the influence of the dc-link voltage on the components like battery stack, machine, inverter and dc-to-dc converter was investigated. A change of the dc-link voltage leads to changes inside the components which affect weight, surface of the semiconductor devices and efficiency. This correlation could be used to develop a simulation process which optimizes the dc-link voltage regarding the programmed targets. In hybrid and electrical vehicles low weight and minimum costs are important and were defined as the main targets to achieve. The vantages which arise by using a dc-to-dc converter can be opposed to the disadvantages which also occur. The additional degree of freedom caused by the dc-to-dc converter shall be used. To achieve the best results regarding efficiency, the dc-link voltage has to be adapted to the operating point of the machine. First of all the dc-to-dc converter is an additional component with its weight, volume and losses. By the increased dc-link voltage on the drive train side, the size of the semiconductor devices inside the inverter could be reduced. Therefore the number of windings inside the machine has to be adapted accordingly. Also the wiring could be decreased based on the reduced currents. Overall there is still a higher weight and volume caused by the dc-to-dc converter. Also the efficiency map is influenced by the dc-to-dc converter. In the base speed region the dc-to-dc converter leads to a higher efficiency because the inverter currents should be reduced by the increased voltage. At high speed and especially high load the double energy conversion leads to a reduced efficiency. Whether a dc-to-dc converter is beneficial for traction systems depends highly on the distribution of the operating points. An inverter with an integrated dc-to-dc converter was developed and constructed for the ''Europa-Hybrid'' project. This hybrid vehicle project was public funded by the German Federal Ministry of Economics and Technology (BMWi). The inverter and the dc-to-dc converter where used to verify the simulation results. Within this thesis the factors of influence, which are in correlation with the dc-link voltage, were analyzed and depicted. The pros and cons of the dc-to-dc converter between the battery and the drive train where pointed out accordingly. (orig.)
Lee, ATL; Sin, JKO; Chan, PCH
2014-01-01
There has been growing interest in Single-Inductor Multiple-Output (SIMO) DC-DC converters due to its reduced cost and smaller form factor in comparison with using multiple single-output converters. An application for such a SIMO-based switching converter is to drive multiple LED strings in a multi-channel LED display. This paper proposes a quasi-hysteretic FSM-based digitally controlled Single-Inductor Dual-Output (SIDO) buck switching LED Driver operating in Discontinuous Conduction Mode (D...
Directory of Open Access Journals (Sweden)
Muhammad Taufiq Ramadhan
2015-03-01
Full Text Available Penggunaan mobil listrik secara umum terkendala pada beban, kecepatan aktual, serta efisiensi energi. Pemanfaatan Fuzzy Logic Controller untuk pengaturan kecepatan motor DC pada mobil listrik diperlukan untuk meraih kecepatan aktual yang lebih presisi sehingga diperoleh efisiensi energi. Selain itu perlu juga menggunakan Bidirectional Buck-Boost Cascade Converter untuk pengaturan motor DC secara bidirectional, yakni pengaturan saat motoring dan saat pengereman regeneratif (regenerative braking. Hal ini berdasar pada energi yang terbuang percuma, baik itu rugi elektris maupun rugi mekanis saat pengereman.
Adaptive Fuzzy Control of a Fuel Cell/DC-DC Convertor System
Fan Li-Ping; Li Chong
2013-01-01
Maintaining a fuel cell system in a correct operating status requires good system control. An adaptive fuzzy control scheme is proposed in this study for the fuel cell/DC-DC converter system to realize constant voltage output under different loads. PID controller and fuzzy controller are used to compare with the proposed adaptive fuzzy controller. Simulation results show that the adaptive fuzzy controller can provide attractive control effects such as faste...
Direct Parallel Connection of DC-DC Power Circuits with Galvanic Isolation
?obanov, Neven
2006-01-01
A DC-DC converter made of two identical IGBT full bridge power circuits is built. The two circuits are directly connected in parallel and driven with only one control circuit originally built for one IGBT bridge. One signal drives two corresponding IGBTs in parallel bridges without any additional circuits for current sharing. The main causes of possible current unbalance were identified by simulation. The difference among transformer leakage inductances has, by far, the most significant influ...
Adaptive Fuzzy Control of a Fuel Cell/DC-DC Convertor System
Directory of Open Access Journals (Sweden)
Fan Li-Ping
2013-01-01
Full Text Available Maintaining a fuel cell system in a correct operating status requires good system control. An adaptive fuzzy control scheme is proposed in this study for the fuel cell/DC-DC converter system to realize constant voltage output under different loads. PID controller and fuzzy controller are used to compare with the proposed adaptive fuzzy controller. Simulation results show that the adaptive fuzzy controller can provide attractive control effects such as faster response characteristic and better steady-state behavior.
Efficient Design to Meet High Power Density Applications Using DC-DC Energy Conversion
Ashok, L.
2014-01-01
In order to meet higher power applications in power electronics system this proposed with implantation using DC-DC energy conversion with resonant converter. Present generation there is a huge amount of markets has increased the demand for high efficiency and high power density applications. But Conventional adopted pulse width modulation includes small weight, low power, low efficiency, due to high switching frequencies in diodes. The proposed system implements a half-bridge ...
Digitally Controlled Point of Load Converter with Very Fast Transient Response
DEFF Research Database (Denmark)
Jakobsen, Lars TÃ¸nnes; Andersen, Michael Andreas E.
2007-01-01
This paper presents a new Digital Self-Oscillating Modulator (DiSOM) that allows the duty cycle to be changed instantly. The DiSOM modulator is shown to have variable switching that is a function of the duty cycle. Compared to a more traditional digital PWM modulator based on a counter and...... comparator the DiSOM modulator allows the sampling frequency of the output voltage control loop to be higher than the switching frequency of the power converter, typically a DC/DC converter. The features of the DiSOM modulator makes it possible to design a digitally controlled DC/DC converter with linear...... voltage mode control and very fast transient response. The DiSOM modulator is combined with a digital PID compensator algorithm is implemented in a hybrid CPLD/FPGA and is used to control a synchronous Buck converter, which is used in typical Point of Load applications. The computational time is only...
A fixed-frequency fast transient response DC–DC controller for VRMs
International Nuclear Information System (INIS)
A 2V-10A fast transient response DC–DC buck controller based on fixed frequency hysteresis control is presented. A carefully designed output voltage filter detects the output capacitor current change which helps the controller to respond immediately after load changes. Adaptive hysteresis control guarantees the switching frequency to be the same as the reference frequency by using a CCII-composed circuit and current mirrors. The controller is designed and fabricated in a TSMC 0.35 ?m process. Simulation and test results show that this controller achieves a 20 ?s settling time in one single switching cycle when load current changes from 1 A to the full load condition at 10 A. (semiconductor integrated circuits)
A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system
DEFF Research Database (Denmark)
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
2014-01-01
Interest on Dielectric ElectroActive Polymer (DEAP) generators has aroused among scientists in recent years, due to the former ones' documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter. On top of that, the shortage of commercially-available, high-efficient, high-voltage, low-power semiconductor devices limits the effective operational range of the power electronic converter. In this paper, a bidirectional tapped-inductor buck-boost converter is proposed, addressing high-efficient high step-up and high step-down voltage conversion ratios, for energy harvesting applications based on DEAP generators. The effective operational range of the converter is extended, by replacing its high-side switch with a string of three serialized MOSFETs, to accommodate the need for high-efficient high-voltage operation. Experiments conducted on a single DEAP generator - part of a quadruple DEAP generator energy harvesting system with all elements installed sequentially in the same circular disk with a 90 phase shift - validate the applicability of the proposed converter, demonstrating energy harvesting of 0.26 J, at 0.5 Hz and 60 % delta-strain; characterized by an energy density of 1.25 J per kg of active material.
Quasi Y-Source Boost DC-DC Converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede
2015-01-01
A new topology called “quasi-Y-source impedance network” is presented in this paper. It inherits all the advantages of the original Y-source network. In addition, the new topology draws continuous current from the source which is required for many renewable sources. It also has dc-current-blocking capacitors, which avoids saturation in the transformer core.
Quasi Y-Source Boost DC-DC Converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang
A new topology called “quasi-Y-source impedance network” is presented in this paper. It inherits all the advantages of the original Y-source network. In addition, the new topology draws continuous current from the source which is required for many renewable sources. It also has dc-current-blockin...
Very High Frequency Half Bridge DC/DC Converter
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
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...
An efficiency improved single-phase PFC converter for electric vehicle charger applications
DEFF Research Database (Denmark)
Zhu, Dexuan; Tang, Yi
2013-01-01
This paper presents an efficiency improved single-phase power factor correction (PFC) converter with its target application to plug-in hybrid electric vehicle (PHEV) charging systems. The proposed PFC converter features sinusoidal input current, three-level output characteristic, and wide range of output DC voltage. Moreover, the involved DC/DC buck conversion stage may only need to convert partial input power rather than full scale of input power, and therefore the system overall efficiency can be much improved. Through proper control of the buck converter, it is also possible to mitigate the double-line frequency ripple power that is inherent in a single-phase AC/DC system. Both simulation and experimental results are presented to show the effectiveness of this converter.
Efficient Power Conversion in Common Active Clamp for Interleaved Dc-Dc Boost
Directory of Open Access Journals (Sweden)
V. Rathinavel Subramaniam
2014-10-01
Full Text Available This project presents a high-efficiency and high-step-up non isolated interleaved dc to dc converter with a common active-clamp circuit. In the presented converter, the coupled-inductor boost converters are interleaved. A boost converter is used to clamp the voltage stresses of all the switches in the interleaved converters, caused by the leakage inductances present in the practical coupled inductors, to a low voltage level. The leakage energies of the inter-leaved converters are collected in a clamp capacitor and recycled to the output by the clamp boost converter. The proposed converter achieves high efficiency because of the recycling of the leakage energies, reduction of the switch voltage stress, mitigation of the output diode is reverse recovery problem, and interleaving of the converters. In many applications, high-efficiency, high-voltage step-up dc–dc converters are required as an interface between the available low voltage sources and the output loads, which are operated at much higher voltages. Examples of such applications are as follows. Different distributed energy storage components such as batteries, fuel cells, and ultra capacitors are used in the power trains of hybrid electric vehicles (HEV, electric vehicles (EV, and fuel cell vehicles (FCV. In the present power train architectures of these vehicles, the voltage levels of the energy storage elements are usually low; whereas the motors of the vehicles are driven at much higher voltages. The telecom and the computer industry utilize the standard batteries, with low voltage levels, as a back-up power source. The dc–dc converter, used in this case, is required to boost the low-input voltage of the batteries to the high voltage of the dc bus. Another example is the automotive headlamps, using the high-intensity discharge lamp ballasts..
A Tapped-Inductor Buck-Boost Converter for a Dielectric ElectroActive Polymer Generator
DEFF Research Database (Denmark)
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
generators. The high-side switch of the converter is replaced by a string of three non-matched, non-thermally-coupled, off-the-shelf MOSFETs, extending its effective operational range. Experiments conducted on a standalone DEAP generator validate the applicability of the proposed converter by demonstrating...
Scientific Electronic Library Online (English)
Erick, Baethge; Alberto, Berzoy; Víctor, Guzmán; María Isabel, Giménez.
2011-09-01
Full Text Available Para obtener la máxima energía de un panel solar es necesario operarlo en el punto de máxima potencia, donde el producto de la tensión fotovoltaica generada y la corriente extraída es un máximo. En operación normal este punto cambia continuamente, lo que requiere de un sistema de seguimiento del pun [...] to de máxima potencia para optimizar la operación del panel. Los paneles solares presentan una característica no lineal en la curva corriente-voltaje, lo que hace difícil la utilización de algoritmos convencionales de seguimiento de puntos de operación donde se busca un máximo o un mínimo. Se ha demostrado que el algoritmo “perturbar y observar” (P&O) es adecuado para el seguimiento del punto de máxima transferencia de potencia sobre este sistema. Este trabajo presenta una simulación en Matlab Simulink del comportamiento del panel solar bajo irradiancias y temperaturas típicas. El modelo se usa para probar que un sistema de seguimiento del punto de máxima potencia del panel basado en el algoritmo P&O operando sobre un control predictivo de corriente aplicado a un convertidor CC-CC es capaz de encontrar y seguir eficientemente el punto de máxima transferencia de potencia frente a variaciones en las condiciones de irradiancia y temperatura en el panel. Abstract in english To get maximum energy from a solar panel it is necessary to operate in the maximum power point where the product of generated photovoltage and extracted current is a maximum. In normal operation this point changes continuously, therefore a maximum power point tracking system is required. Solar panel [...] s present a nonlinear characteristic in the current-voltage graph, complicating the use of standard operating point tracking algorithms to find a maximum power point. If has been shown that the "perturb and observe" (P&O) algorithm is adequate to achieve this task. This work presents a Simulink Matlab simulation of the solar panel behavior under constant irradiation and typical temperatures. This simulation is used to prove that a maximum power point tracking control based on the P&O algorithm manipulating a predictive current control applied to a DC-DC converter is able to find and efficiently follow the maximum power point under panel irradiance and temperature variations.
Park, Sung-Yun; Cho, Jihyun; Lee, Kyuseok; Yoon, Euisik
2015-12-01
We report a pulse width modulation (PWM) buck converter that is able to achieve a power conversion efficiency (PCE) of > 80% in light loads 100 Î¼A) for implantable biomedical systems. In order to achieve a high PCE for the given light loads, the buck converter adaptively reconfigures the size of power PMOS and NMOS transistors and their gate drivers in accordance with load currents, while operating at a fixed frequency of 1 MHz. The buck converter employs the analog-digital hybrid control scheme for coarse/fine adjustment of power transistors. The coarse digital control generates an approximate duty cycle necessary for driving a given load and selects an appropriate width of power transistors to minimize redundant power dissipation. The fine analog control provides the final tuning of the duty cycle to compensate for the error from the coarse digital control. The mode switching between the analog and digital controls is accomplished by a mode arbiter which estimates the average of duty cycles for the given load condition from limit cycle oscillations (LCO) induced by coarse adjustment. The fabricated buck converter achieved a peak efficiency of 86.3% at 1.4 mA and > 80% efficiency for a wide range of load conditions from 45 Î¼A to 4.1 mA, while generating 1 V output from 2.5-3.3 V supply. The converter occupies 0.375 mm(2) in 0.18 Î¼m CMOS processes and requires two external components: 1.2 Î¼F capacitor and 6.8 Î¼H inductor. PMID:26742139
A Single Phase to Three Phase PFC Half-Bridge Converter Using BLDC Drive with SPWM Technique.
Srinu Duvvada; Manmadha Kumar B
2014-01-01
In this paper, a buck half-bridge DC-DC converter is used as a single-stage power factor correction (PFC) converter for feeding a voltage source inverter (VSI) based permanent magnet brushless DC motor (BLDC) drive. The front end of this PFC converter is a diode bridge rectifier (DBR) fed from single-phase AC mains. The BLDC is used to drive a compressor load of an air conditioner through a three-phase VSI fed from a controlled DC link voltage. The speed of the compressor is controlled to ach...
Closed-Form Critical Conditions of Subharmonic Oscillations for Buck Converters
Fang, Chung-Chieh
2012-01-01
A general critical condition of subharmonic oscillation in terms of the loop gain is derived. Many closed-form critical conditions for various control schemes in terms of converter parameters are also derived. Some previously known critical conditions become special cases in the generalized framework. Given an arbitrary control scheme, a systematic procedure is proposed to derive the critical condition for that control scheme. Different control schemes share similar forms of critical conditions. For example, both V2 control and voltage mode control have the same form of critical condition. A peculiar phenomenon in average current mode control where subharmonic oscillation occurs in a window value of pole can be explained by the derived critical condition. A ripple amplitude index to predict subharmonic oscillation proposed in the past research has limited application and is shown invalid for a converter with a large pole.
A Tapped-Inductor Buck-Boost Converter for a Dielectric ElectroActive Polymer Generator
DEFF Research Database (Denmark)
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
2014-01-01
Energy harvesting applications based on Dielectric ElectroActive Polymer (DEAP) generators have been in the spotlight in recent years after the latter ones’ documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter....
Stratégies de commande numérique pour un convertisseur DC/DC SEPIC en vue de l'intégration
Li, Nan
2012-01-01
L'utilisation des alimentations à découpage (SMPSs : switched mode power supplies) est à présent largement répandue dans des systèmes embarqués en raison de leur rendement. Les exigences technologiques de ces systèmes nécessitent simultanément une très bonne régulation de tension et une forte compacité des composants. SEPIC (Single-Ended Primary Inductor Converter) est un convertisseur à découpage DC/DC qui possède plusieurs avantages par rapport à d'autres convertisseurs de structure classiq...
Directory of Open Access Journals (Sweden)
Tiara Freitas
2015-09-01
Full Text Available A new application of the three-phase buck-resonant converter is presented in this paper. It is shown that the analyzed converter is suitable to operate as the rectifier stage in low power wind energy conversion systems (WECS based on permanent magnet synchronous generators (PMSG with variable wind speed. As main features, it presents a single controlled switch, simple implementation and control, and operates with a high power factor and low harmonic distortion over all wind speed ranges. The converter topology, its design equations and its operation are presented, as well as the simulation results of the PMSG based conversion system. From the analysis carried out in the paper it is concluded that the converter is indicated to be employed in distributed generation and hybrid systems where wind generation is associated with other sources.
Feld, Lutz Werner; Klein, Katja; Lipinski, Martin; Preuten, Marius; Rauch, Max Philip; Schmitz, Stefan Antonius; Wlochal, Michael
2016-01-01
The CMS pixel detector will be exchanged during the technical stop 2016/2017. To allow the new pixel detector to be powered with the legacy cable plant and power supplies, a novel powering scheme based on DC-DC conversion is employed. After the successful conclusion of an extensive development and prototyping phase, mass production of 1800 DC-DC converters as well as motherboards and other power PCBs has now been completed. This contribution reviews the lessons learned from the development of the power system for the Phase-1 pixel detector, and summarizes the experience from the production phase.
Feld, Lutz Werner; Klein, Katja; Lipinski, Martin; Preuten, Marius; Rauch, Max Philip; Schmitz, Stefan Antonius; Wlochal, Michael
2015-01-01
The testing program is outlined, results from mass production are presented and issues that have been encountered are described. In addition, two system level challenges, namely the choice of output voltage in the presence of large, load-dependent voltage drops, and the thermal management required to remove the heat load caused by the DC-DC converters, are discussed.
Directory of Open Access Journals (Sweden)
Leila Mohammadian
2015-03-01
Full Text Available In this paper, a new method of signal flow graph technique and Masonâ€™s gain formula are applied for extracting the model and transfer functions from control to output and from input to output of a buck-boost converter. In order to investigate necessity of a controller for the converter with assumed parameters, the frequency and time domain analysis is done and the open loop system characteristics are verified. In addition, the needed closed loop controlled system specifications are determined. Moreover, designing a controller for the mentioned converter system based on the extracted model is discussed. For this purpose, a proportional-integral-derivative (PID controller is designed and the hybrid of genetic algorithm (GA and particle swarm optimization (PSO, called H-GA-PSO method is used for tuning of the PID controller. Finally, the simulation results are used to show the performance of the proposed modeling and regulation methods.
DEFF Research Database (Denmark)
Rødgaard, Martin Schøler; Andersen, Thomas; Meyer, Kaspar Sinding; Andersen, Michael A. E.
2012-01-01
Research and development within piezoelectric transformer (PT) based converters are rapidly increasing as the technology is maturing and starts to prove its capabilities. Especially for high voltage and high step-up applications, PT based converters have demonstrated good performance and DC/AC co...... switching optimised PT, capable of generating output voltages higher than 2kV from a 24V supply voltage. Furthermore finite element method (FEM) has been the main tool through the PT development.......Research and development within piezoelectric transformer (PT) based converters are rapidly increasing as the technology is maturing and starts to prove its capabilities. Especially for high voltage and high step-up applications, PT based converters have demonstrated good performance and DC....../AC converters are widely used commercially. The availability of PT based converters for DC/DC applications are very limited and are not that developed yet. I this paper an interleaved multi layer Rosen-type PT for high step-up and high output voltage is developed, for driving a 2.5kV dielectric electro active...
Scientific Electronic Library Online (English)
Lina, Morales Laguado; Harold, Chamorro; Jairo, Soriano.
2009-12-01
Full Text Available Este trabajo propone el análisis y diseño de dos estrategias de control para un conversor CC-CC reductor de corriente permanente. Tal tipo de dispositivos de electrónica de potencia convierten una tensión continua a otra de menor magnitud y cuyas características de no linealidad son evidenciadas. Se [...] presentan entonces, dos técnicas de control no lineal, la primera propuesta es un control óptimo PI (error proporcional e integral del error) convencional, basado en la minimización del criterio ITSE (integral del cuadrado del error ponderado en el tiempo). Para ello se obtiene un modelo de la planta en un punto de operación. La segunda propuesta es un control difuso cuyos conjuntos de entrada y salida son también definidos minimizando el criterio ITSE en el sistema general, y estableciendo como entradas el error proporcional y la integral del error. A continuación se realiza una variación de la carga para establecer la eficiencia del sistema con los dos controladores mencionados. Se debe tener en cuenta que este tipo de sistemas no debe presentar sobretensiones considerables, ya que puede ocasionar daño en él. En este sentido, los parámetros encontrados en el diseño de los dos controladores corresponden a una metodología analítica y descriptiva. Los resultados obtenidos en simulación, y estableciendo como figura de mérito el índice de desempeño mencionado (ITSE) y el consumo de potencia, muestra que la respuesta del sistema para el control difuso presenta un mayor consumo de potencia que el control óptimo, mientras que el ITSE obtenido es mayor para el control óptimo que para el difuso. Se concluye que la exploración de este tipo de conversores, utilizando técnicas de control no lineal y minimizando los diferentes índices de desempeño, es aplicable. Abstract in english This document proposes analysing and designing two control strategies for permanent current DC-DC buck converter. These kinds of electronic devices convert a constant-voltage to a lower constant-voltage (nonlinearity characteristics being demonstrated). Two nonlinear control techniques are shown. Th [...] e first is a conventional optimal proportional error and integral error (PI) controller based on minimising integral of time per squared errors (ITSE) criteria. A model of the plant at an operation point was thus obtained. The second one was fuzzy control where input and output sets were also defined by minimising ITSE criteria in the overall system and establishing inputs such as proportional error and integral error. Load was then varied to establish the system's efficiency with both the aforementioned controllers. It must be borne in mind that such systems should not present supervoltage since this can cause damage. The parameters found in designing both controllers thus corresponded to analytical and descriptive methodology. Simulation results, the performance index mentioned above (ITSE) and power consumption showed that the system's response for the fuzzy control drew more power consumption than the optimal controller; otherwise, obtained ITSE was larger for the optimal control than the fuzzy control. It is concluded that exploring these types of converter is applicable when using nonlinear control techniques and minimising the different performance indices.
Series Connected Converter for Control of Multi-Bus Spacecraft Power Utility
Beach, Raymond F. (Inventor); Brush, Andy (Inventor)
1997-01-01
The invention provides a power system using series connected regulators. Power from a source, such as a solar array, is processed through the regulators and provided to corresponding buses used to charge a battery and supply loads. The regulators employ a bypass loop around a DC-DC converter. The bypass loop connects a hot input of the converter to a return output, preferably though an inductor. Part of the current from the source passes through the bypass loop to the power bus. The converter bucks or boosts the voltage from the source to maintain the desired voltage at the bus. Thus, only part of the power is processed through the converter. The converter can also be used without the bypass loop to provide isolation. All of the converters can be substantially identical.
International Nuclear Information System (INIS)
In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC—DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated post-regulator DC—DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis. (general)
Wang, Fa-Qiang; Zhang, Hao; Ma, Xi-Kui
2012-02-01
In this paper, period-doubling bifurcation in a two-stage power factor correction converter is analyzed by using the method of incremental harmonic balance (IHB) and Floquet theory. A two-stage power factor correction converter typically employs a cascade configuration of a pre-regulator boost power factor correction converter with average current mode control to achieve a near unity power factor and a tightly regulated post-regulator DC—DC Buck converter with voltage feedback control to regulate the output voltage. Based on the assumption that the tightly regulated post-regulator DC—DC Buck converter is represented as a constant power sink and some other assumptions, the simplified model of the two-stage power factor correction converter is derived and its approximate periodic solution is calculated by the method of IHB. And then, the stability of the system is investigated by using Floquet theory and the stable boundaries are presented on the selected parameter spaces. Finally, some experimental results are given to confirm the effectiveness of the theoretical analysis.
Parallel connection of high-power DC/DC power supply based on IGBT device
International Nuclear Information System (INIS)
Parallel connection technique of DC/DC power supplies is adopted, and DC high-power supply is designed based on IGBT device, which can be used as the plasma displacement fast control power supply for EAST device. Based on the simulation and experiment, satisfactory dynamic and static performance of the DC/DC power supply was obtained. (authors)
Efficient Hybrid Optimal Design Method for Power Electronics Converters
AUTHOR|(SzGeCERN)697719; Aguglia, Davide; Viarouge, Philippe; Cros, Jérôme
2015-01-01
This paper presents a novel design methodology for dimensioning optimal power-electronic converters, which is able to achieve the precision of numerical simulation-based optimization procedures, however minimizing the overall computation time. The approach is based on the utilization of analytical and frequency-domain design models for a numerical optimization process, a validation with numerical simulations of the intermediate optimal solutions, and the correction of the analytical design models precision from the numerical simulation results. This method allows using the numerical simulation in an efficient way, where typically less than ten correction iterations are required. In order to demonstrate the performances of the proposed methodology, the calculation of the control parameters for an H-bridge DC-DC converter and the optimal dimensioning of a damped output filter for a buck converter using the proposed approach is presented.
DEFF Research Database (Denmark)
Tang, Yi; Zhu, Dexuan; Jin, Chi; Wang, Peng; Blaabjerg, Frede
2015-01-01
voltages, and it will be very suitable for high-power applications where the output voltage can be either lower or higher than the peak ac input voltage, e.g., plug-in hybrid electric vehicle charging systems. Moreover, the involved dc/dc buck conversion stage may only need to process partial input power...... voltage will be fairly constant. The dynamic response of this regulation loop is also very fast and the system is therefore insensitive to external disturbances. Both simulation and experimental results are presented to show the effectiveness of this converter as well as its efficiency improvement against...
Low-to-Medium Power Single Chip Digital Controlled DC-DC Regulator for Point-of-Load Applications
Adell, Philippe C. (Inventor); Bakkaloglu, Bertan (Inventor); Vermeire, Bert (Inventor); Liu, Tao (Inventor)
2015-01-01
A DC-DC converter for generating a DC output voltage includes: a digitally controlled pulse width modulator (DPWM) for controlling a switching power stage to supply a varying voltage to an inductor; and a digital voltage feedback circuit for controlling the DPWM in accordance with a feedback voltage corresponding to the DC output voltage, the digital voltage feedback circuit including: a first voltage controlled oscillator for converting the feedback voltage into a first frequency signal and to supply the first frequency signal to a first frequency discriminator; a second voltage controlled oscillator for converting a reference voltage into a second frequency signal and to supply the second frequency signal to a second frequency discriminator; a digital comparator for comparing digital outputs of the first and second frequency discriminators and for outputting a digital feedback signal; and a controller for controlling the DPWM in accordance with the digital feedback signal.
Auda, Milan; MilanoviÄ, Miro; RoÅ¡kariÄ, Andrej
2000-01-01
The paper describes a double-back and boost converter structure suittable for battery charger in electrical vehicle application. It is very convenient to use inverter elements for battery charging task. Different DC to DC converter structures can be organized from the inverter semiconductor elements. In the case of the induction motor electrical drive application, the required inductors could be established from the motor windings. Such combined converter should satisfy the unity power factor...
Compherensive Design of a 100 kW/400 V High Performance AC-DC Converter
Directory of Open Access Journals (Sweden)
Ghasem Esfandiari
2015-01-01
Full Text Available In this paper, a comprehensive design for a 100kW/400V, three-phase pulse-width modulated (PWM AC-DC converter is presented that serves as the front-end power supply for wide-range varying active load. This power supply includes two series stages; a six-switch AC-DC boost converter and a DC-DC buck converter to regulate 400VDC at load side. The design of all inductors and capacitors is fulfilled using mathematical expressions. In addition, small signal modelling and controller design are presented in order to raise the design efficiency of the proposed converter. Also, due to the high power application, improved soft-switching techniques are applied. Furthermore, systematic approach to design an input EMI filter for DC-DC converter is explained. The simulation results performed by PSCAD software show that high performance of the proposed power supply is obtained in terms of stability, high power factor, high efficiency and low total harmonic distortion (THD.
Nejati, R.; Eshtehardiha, S.; Poudeh, M. Bayati
2008-10-01
The DC converter can be employed alone for the stabilization or the control of DC voltage of a battery or it can be a component of a complex converter to control the intermediate or output voltages. Due to the switching property included in their structure, DC-DC converters have a non-linear behavior and their controlling design is accompanied with complexities. But by employing the average method it is possible to approximate the system by a linear system and then linear control methods can be used. Dynamic performance of buck converters output voltage can be controlled by methods of Linear Quadratic Regulator (LQR) and PID. The former controller designing needs to positive definite matrix selection and the later is relative to desired pole places in complex coordinate. In this article, matrixes coefficients and the best constant values for PID controllers are selected based on Genetic algorithm method. The simulation results show an improvement in voltage control response.
A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system
DEFF Research Database (Denmark)
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
operational range of the converter is extended, by replacing its high-side switch with a string of three serialized MOSFETs, to accommodate the need for high-efficient high-voltage operation. Experiments conducted on a single DEAP generator - part of a quadruple DEAP generator energy harvesting system with...
A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system
DEFF Research Database (Denmark)
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
2014-01-01
Interest on Dielectric ElectroActive Polymer (DEAP) generators has aroused among scientists in recent years, due to the former ones' documented advantages against competing electromagnetic and field-activated technologies. Yet, the need for bidirectional energy flow under high step-up and high step-down voltage conversion ratios, accompanied by low-average but relatively high-peak currents, imposes great challenges on the design of the employed power electronic converter. On top of that, the sho...
Investigation of Buck Converter Radiated Emissions (150 kHz - 30 MHz) Measured according to CISPR 25
Murase, John Takeshi
2013-01-01
Electromagnetic compatibility and compliance with relevant standards is imperative for commercial success for any type of electronic equipment. Since more and more electronics are constantly added into today’s vehicles, this is a highly significant matter in the automotive business. The primary source of electric energy in an on-road vehicle is typically a 12 or 24 volt battery; this makes voltage step down converters ubiquitous in virtually any automotive electronic system. In strive for eve...
Directory of Open Access Journals (Sweden)
Ali Siblini
2012-08-01
Full Text Available This paper presents the conception, fabrication and characterization of integrated inductors containing magnetic layers. We require different steps of micro-technologies: preparation of glass and ferrite substrates, RF sputtering, photolithography, etching and finally electroplating techniques for copper and gold films. The geometrical magnitudes are determined by using HFSS simulator software. The measurements performed at low and high frequencies (up to 1 GHz permit to verify the correlation between experiment and simulation results. The inductance of the manufactured spiral inductor is ??about 200 nH and it is constant from low frequency up to 0.9 GHz.
Performance Analysis of Various DC-DC Converters with Optimum Controllers for PV Applications
R. Sankarganesh; S. Thangavel
2014-01-01
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 ...
A DC-DC Converter-Based PEM Fuel Cell System Emulator
Rezzak, Daoud; Khoucha, Farid; Benbouzid, Mohamed; Kheloui, Abdelaziz; Mamoune, Abdeslam
2011-01-01
The Proton Exchange Membrane Fuel Cell (PEMFC) is being investigated as an alternate power source for various applications as transportation and emergency power supplies. Fuel cell systems are characterized by high costs and complex auxiliary devices. For this reason, a fuel cell emulator can be used as a suitable and economic alternative to a real one for developing and testing a fuel cell power conditioning system. The fuel cell emulator must be able to reproduce the FC nonlinear output vol...
Physics of Failure Models for Capacitor Degradation in DC-DC Converters
National Aeronautics and Space Administration â€” This paper proposes a combined energy-based model with an empirical physics of failure model for degradation analysis and prognosis of electrolytic capacitors in...
Analysis and design of multicell DC/DC converters using vectorized models
Meynard, Thierry
2015-01-01
Shows how the concepts of vectorization and design masks can be used to help the designer in comparing different designs and making the right choices. The book addresses series and parallel multicell conversion directly, and the concepts can be generalized to describe other topologies.
Modular DC/DC Converter for DC Distribution and Collection Networks
Kenzelmann, Stephan
2012-01-01
A major change in the electrical transmission and distribution system is taking place in Europe at the moment. The shift from a centralised energy production to a distributed generation profoundly changes the behaviour of the grid. Environmental or social issues associated with the construction of new power lines to relieve bottlenecks, together with aged equipment dating from the 1960s, pose some serious challenges to government, the research communi...
Modeling and control of isolated full bridge boost DC-DC converter implemented in FPGA
DEFF Research Database (Denmark)
Taeed, Fazel; Nymand, M.
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....
The use of power DC-DC converters and gyrator structures for energy processing
MartÃnez GarcÃa, Herminio
2014-01-01
This article provides a classification of high efficiency switching power-gyrator structures and their use as cells for energy processing in photovoltaic solar facilities. Having into account the properties of these topologies presented in the article, their inclusion in solar facilities allows increasing the performance of the whole installation. Thus, the design, simulation and implementation of a G-type power gyrator are carried out throughout the text. In addition, in order to obtain the ...
Power factor controller used as DC-DC converter for photovoltaic sources
Energy Technology Data Exchange (ETDEWEB)
Mukerjee, A.K.; Dasgupta, Nivedita [Centre for Energy Studies, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016 (India)
2008-06-15
An active power factor controller (PFC) integrated circuit, normally used in AC circuits, has been used for DC-to-DC boost conversion with a stable output voltage for a variable DC input voltage as obtained from photovoltaic (PV) sources. The circuit described here uses a power factor controller MC 34262 to give approximately 400 V{sub DC} output for an input variation from 90 to 280 V{sub DC}. The maximum efficiency achieved was 98% at 450 W. Comparisons between AC and DC operations have been made. (author)
PV and Wind Energy Hybrid Integrated Full-Bridge-DC–DC Converter for a Residential Application
G.Revan Sidda; Mohandas. Audirala; Mohammed Mustafa
2014-01-01
Hybrid power system can be used to reduce energy storage requirements. There is increasing demand for the use of alternate or renewable energy sources to achieve clean and low-cost electricity for Residential Application The PV-wind hybrid system returns the lowest unit cost values to maintain the same level of DPSP as compared to standalone solar and wind systems. For all load demands the levelised energy cost for PV-wind hybrid system is always lower than that of standalone solar PV or wind...
FC/Battery Power Management for Electric Vehicle Based Interleaved DC-DC Boost Converter Topology
Benrabah, Ali; Khoucha, Farid; Herizi, Omar; Benbouzid, Mohamed; Kheloui, Abdelaziz
2013-01-01
Due to the fact that the environmental issues have become more serious recently, interest in renewable energy systems, such as, fuel-cells (FCs) has increased steadfastly. Among many types of FCs, proton exchange membrane FC (PEMFC) is one of the most promising power sources due to its advantages, such as, low operation temperature, high power density and low emission. However, using only PEMFC for electric vehicle may not be feasible to satisfy the peak demand changes especially during accel...
Basic circuits to design switched-based DC-DC converters
Directory of Open Access Journals (Sweden)
F. Sandoval-Ibarra
2007-01-01
Full Text Available El propósito de este artículo es doble. Por un lado, se presentan conceptos básicos de circuitos conmutados para diseñar un convertidor CD–CD y, por el otro, se rescatan definiciones de electrónica de potencia asociadas a redes eléctricas simples. En el análisis de esas redes es necesario tomar en cuenta no solo las no idealidades de los convertidores sino también cómo minimizar pérdidas de potencia. Porque las perdidas de potencia pueden ser minimizadas aumentando la frecuencia de reloj de los convertidores conmutados, se presentan resultados experimentales de generadores de reloj. Estos circuitos fueron implementados con componentes de bajo costo.
Design and Implementation of Digital Current Mode Controller for DC-DC Converters
DEFF Research Database (Denmark)
Taeed, Fazel
controllers (including PCMC) are sensitive to temperature drift, component aging and noise. Digital controllers do not have the aforementioned drawbacks of analog controllers; but they have lower bandwidth than analog controllers due to the sampling and calculation delays. Generally, analog controllers have a...
Fan, Haifeng
2011-12-01
The distributed renewable energy generation and utilization are constantly growing, and are expected to be integrated with the conventional grid. The growing pressure for innovative solutions will demand power electronics to take an even larger role in future electric energy delivery and management systems, since power electronics are required for the conversion and control of electric energy by most dispersed generation systems Furthermore, power electronics systems can provide additional intelligent energy management, grid stability and power quality capabilities. Medium-voltage isolated dc-dc converter will become one of the key interfaces for grid components with moderate power ratings. To address the demand of medium voltage (MV) and high power capability for future electric energy delivery and management systems, the power electronics community and industry have been reacting in two different ways: developing semiconductor technology or directly connecting devices in series/parallel to reach higher nominal voltages and currents while maintaining conventional converter topologies; and by developing new converter topologies with traditional semiconductor technology, known as multilevel converters or modular converters. The modular approach uses the well-known, mature, and cheaper power semiconductor devices by adopting new converter topologies. The main advantages of the modular approach include: significant improvement in reliability by introducing desired level of redundancy; standardization of components leading to reduction in manufacturing cost and time; power systems can be easily reconfigured to support varying input-output specifications; and possibly higher efficiency and power density of the overall system. Input-series output-parallel (ISOP) modular configuration is a good choice to realize MV to low voltage (LV) conversion for utility application. However, challenges still remain. First of all, for the high-frequency MV utility application, the low switching loss and conduction loss are must-haves for high efficiency, while bidirectional power flow capability is a must for power management requirement. To address the demand, the phase-shift dual-halfbridge (DHB) is proposed as the constituent module of ISOP configuration for MV application. The proposed ISOP DHB converter employs zero-voltage-switching (ZVS) technique combined with LV MOSFETs to achieve low switching and conduction losses under high frequency operation, and therefore high efficiency and high power density, and bidirectional power flow as well. Secondly, a large load range of high efficiency is desired rather than only a specific load point due to the continuous operation and large load variation range of utility application, which is of high importance because of the rising energy cost. This work proposes a novel DHB converter with an adaptive commutation inductor. By utilizing an adaptive inductor as the main energy transfer element, the output power can be controlled by not only the phase shift but also the commutation inductance, which allows the circulating energy to be optimized for different load conditions to maintain ZVS under light load conditions and minimize additional conduction losses under heavy load conditions as well. As a result, the efficiency at both light and heavy load can be significantly improved compared with the conventional DHB converter, and therefore extended high-efficiency range can be achieved. In addition, current stress of switch devices can be reduced. The theoretical analysis is presented and validated by the experimental results on a 50 kHz, 1 kW dc-dc converter module. Thirdly, input-voltage sharing and output-current sharing are critical to assure the advantages of the ISOP modular configuration. To solve this issue, an identically distributed control scheme is proposed in this work. The proposed control scheme, using only one distributed voltage loop to realize both input-voltage and output-current sharing, provides plug-and-play capability, possible high-level fault tolerance, and easy implementatio
Recovery Act: Integrated DC-DC Conversion for Energy-Efficient Multicore Processors
Energy Technology Data Exchange (ETDEWEB)
Shepard, Kenneth L
2013-03-31
In this project, we have developed the use of thin-film magnetic materials to improve in energy efficiency of digital computing applications by enabling integrated dc-dc power conversion and management with on-chip power inductors. Integrated voltage regulators also enables fine-grained power management, by providing dynamic scaling of the supply voltage in concert with the clock frequency of synchronous logic to throttle power consumption at periods of low computational demand. The voltage converter generates lower output voltages during periods of low computational performance requirements and higher output voltages during periods of high computational performance requirements. Implementation of integrated power conversion requires high-capacity energy storage devices, which are generally not available in traditional semiconductor processes. We achieve this with integration of thin-film magnetic materials into a conventional complementary metal-oxide-semiconductor (CMOS) process for high-quality on-chip power inductors. This project includes a body of work conducted to develop integrated switch-mode voltage regulators with thin-film magnetic power inductors. Soft-magnetic materials and inductor topologies are selected and optimized, with intent to maximize efficiency and current density of the integrated regulators. A custom integrated circuit (IC) is designed and fabricated in 45-nm CMOS silicon-on-insulator (SOI) to provide the control system and power-train necessary to drive the power inductors, in addition to providing a digital load for the converter. A silicon interposer is designed and fabricated in collaboration with IBM Research to integrate custom power inductors by chip stacking with the 45-nm CMOS integrated circuit, enabling power conversion with current density greater than 10A/mm2. The concepts and designs developed from this work enable significant improvements in performance-per-watt of future microprocessors in servers, desktops, and mobile devices. These new approaches to scaled voltage regulation for computing devices also promise significant impact on electricity consumption in the United States and abroad by improving the efficiency of all computational platforms. In 2006, servers and datacenters in the United States consumed an estimated 61 billion kWh or about 1.5% of the nation's total energy consumption. Federal Government servers and data centers alone accounted for about 10 billion kWh, for a total annual energy cost of about $450 million. Based upon market growth and efficiency trends, estimates place current server and datacenter power consumption at nearly 85 billion kWh in the US and at almost 280 billion kWh worldwide. Similar estimates place national desktop, mobile and portable computing at 80 billion kWh combined. While national electricity utilization for computation amounts to only 4% of current usage, it is growing at a rate of about 10% a year with volume servers representing one of the largest growth segments due to the increasing utilization of cloud-based services. The percentage of power that is consumed by the processor in a server varies but can be as much as 30% of the total power utilization, with an additional 50% associated with heat removal. The approaches considered here should allow energy efficiency gains as high as 30% in processors for all computing platforms, from high-end servers to smart phones, resulting in a direct annual energy savings of almost 15 billion kWh nationally, and 50 billion kWh globally. The work developed here is being commercialized by the start-up venture, Ferric Semiconductor, which has already secured two Phase I SBIR grants to bring these technologies to the marketplace.
Grid converter for LED based intelligent light sources
DEFF Research Database (Denmark)
Török, Lajos
2011-01-01
The purpose of this thesis was to investigate the applicability and effects of digital control to line connected switched mode power supplies with power factor correction. The main approach was cost effectiveness with high efficiency. This involved hardware design for increased switching frequency to reduce the size of the magnetic components. A description of different grid regulations was given followed by a set of converter topologies and controllers. Different control techniques were pointed out. Among the listed topologies and control solutions few were selected for further analysis, design and implementation. Many of different hardware and control solutions available on the market were investigated. Most of the commercial power supplies are controlled by dedicated analog controllers in form an integrated circuit. Thus a survey was conducted to analyze the available state-of-art analog controllers and their implemented control algorithms. As digital control has to be competitive with the existing solutions it was investigated what digital signal processing solutions exist. A performance and cost comparison was also presented. The chosen converter topologies were thoroughly analyzed. Different converters were chosen for different power levels. At low power simple boost converter as power factor corrector (PFC) and a RCD-clamped forward converter was chosen as DC-DC converter. This with has double output and coupled lter inductor. To design a digital controller with the tools of the classical control theory a small signal linearized model of the converter is needed. Detailed modeling and linearizing of the boost converter is presented. At high power level interleaving technique is frequently used to reduce the current stress on the switching components. Though the number of magnetic components is increased they became smaller in size resulting in smaller current ripple through them. An interleaved boost converter with two legs is selected as PFC converter. It was shown that the small signal model of the interleaved converter is similar to the simple boost converter. Only the simple inductor has to be replaced by the paralleled inductors of each leg. This statement is valid only if the total inductor current is controlled rather than controlling the current in each leg. As second stage a phase-shifted full-bridge converter with synchronous rectication and current doubler was selected. It was shown that for output current and voltage control this topology can be modeled as a interleaved synchronous buck converter. As it can be seen interleaving technique is also present in this topology. For this topology a fuzzy logic voltage controller is proposed and compared to the traditional PI controller. After modeling the converters controllers can be designed. The controller design was interconnected with the hardware design and control platform. Thus two dfferent prototypes were designed and built with two dierent digital controllers and the controller design, analysis and implementation was based on these two case studies. The first prototype was a 70 W two-stage PFC and DC-DC converter with boost and forward converters. Average current mode control was selected, designed, simulated an implemented for the boost PFC converter. The two-loop control structure (fast internal current loop and lower bandwidth external voltage loop) was designed for nominal power but system behavior was also analyzed for low-load conditions. The controller was simulated in Matlab/Simulink using PLECS library and embedded Matlab function. All the parameters were treated and scaled just as they appear in the ADC interrupt of the 16 bit fixed point dsPIC30F1010 microcontroller. Peak current control was implemented for the forward converter, using analog comparator module of the digital-signal controller. The waveforms, eciency and power factor results were compared to the performance of an identical two stage 70 W power supply controlled with an analog PFC/PWM integrated circuit. The second prototype was a 600 W two-stage PFC and DC-DC converter with
Energy Technology Data Exchange (ETDEWEB)
Sammet, Jan
2014-03-18
The instantaneous luminosity of the LHC is expected to reach 2 x 10{sup 34} s{sup -1}cm{sup -2} and 5 x 10{sup 34} s{sup -1}cm{sup -2} around the years 2019 and 2024, respectively. After the second upgrade the LHC will be referred to as the High Luminosity LHC (HL-LHC). In order to benefit from the higher luminosities, CMS foresees to upgrade its pixel detector during an extended winter shutdown of the LHC at the end of 2016 and the beginning of 2017. During a long shutdown of the LHC over the years 2022 and 2023, it is foreseen to install a completely new tracking system in CMS. Both upgrades are expected to result in the need to provide more electric current to the detector. However, power losses in cables already contribute 50% to the power consumption of the present tracker and rise with the current squared. Since no more space is available for cables, and thicker cables within the tracking volume spoil the material budget of the detector, new powering schemes are considered mandatory. CMS foresees the use of radiation tolerant DC-DC converters on the front-end to reduce power losses on cables. This thesis describes the new powering scheme of the CMS pixel detector and discusses the options with respect to a new strip tracker. A radiation and magnetic field tolerant DC-DC converter prototype, the PIXV8A, is introduced and the research that led to its development is summarised. The PIXV8A has been developed for the application in the pixel upgrade and is also a first approach for a DC-DC converter for the later upgrade of the CMS tracking system. The PIXV8A makes use of the AMIS4 chip, which has been proven to stay operational for total ionising doses of up to 1 MGy and fluences of up to 10{sup 15} n{sub eq}/cm{sup 2}. With an input voltage of 10 V, the PIXV8A converter provides an efficiency of about 80% for output voltages of 2.5 V and 3.0 V. Within this thesis the robustness of the novel powering scheme and the qualification of the PIXV8A are demonstrated in several tests, including system test measurements with silicon strip detector modules and silicon pixel detector modules in combination with an evaporative CO{sub 2} cooling system.
International Nuclear Information System (INIS)
The instantaneous luminosity of the LHC is expected to reach 2 x 1034 s-1cm-2 and 5 x 1034 s-1cm-2 around the years 2019 and 2024, respectively. After the second upgrade the LHC will be referred to as the High Luminosity LHC (HL-LHC). In order to benefit from the higher luminosities, CMS foresees to upgrade its pixel detector during an extended winter shutdown of the LHC at the end of 2016 and the beginning of 2017. During a long shutdown of the LHC over the years 2022 and 2023, it is foreseen to install a completely new tracking system in CMS. Both upgrades are expected to result in the need to provide more electric current to the detector. However, power losses in cables already contribute 50% to the power consumption of the present tracker and rise with the current squared. Since no more space is available for cables, and thicker cables within the tracking volume spoil the material budget of the detector, new powering schemes are considered mandatory. CMS foresees the use of radiation tolerant DC-DC converters on the front-end to reduce power losses on cables. This thesis describes the new powering scheme of the CMS pixel detector and discusses the options with respect to a new strip tracker. A radiation and magnetic field tolerant DC-DC converter prototype, the PIXV8A, is introduced and the research that led to its development is summarised. The PIXV8A has been developed for the application in the pixel upgrade and is also a first approach for a DC-DC converter for the later upgrade of the CMS tracking system. The PIXV8A makes use of the AMIS4 chip, which has been proven to stay operational for total ionising doses of up to 1 MGy and fluences of up to 1015 neq/cm2. With an input voltage of 10 V, the PIXV8A converter provides an efficiency of about 80% for output voltages of 2.5 V and 3.0 V. Within this thesis the robustness of the novel powering scheme and the qualification of the PIXV8A are demonstrated in several tests, including system test measurements with silicon strip detector modules and silicon pixel detector modules in combination with an evaporative CO2 cooling system.
Kazimierczuk, Marian K
2012-01-01
This book is devoted to resonant energy conversion in power electronics. It is a practical, systematic guide to the analysis and design of various dc-dc resonant inverters, high-frequency rectifiers, and dc-dc resonant converters that are building blocks of many of today's high-frequency energy processors. Designed to function as both a superior senior-to-graduate level textbook for electrical engineering courses and a valuable professional reference for practicing engineers, it provides students and engineers with a solid grasp of existing high-frequency technology, while acquainting them wit
Zhu, Lizhi (Canton, MI)
2007-11-13
A power converter architecture interleaves full bridge converters to alleviate thermal management problems in high current applications, and may, for example, double the output power capability while reducing parts count and costs. For example, one phase of a three phase inverter is shared between two transformers, which provide power to a rectifier such as a current doubler rectifier to provide two full bridge DC/DC converters with three rather than four high voltage inverter legs.
Scientific Electronic Library Online (English)
J, Linares-Flores; A, Antonio-García; A, Orantes-Molina.
2011-06-01
Full Text Available En este artículo se presenta el diseño e implementación de un controlador de velocidad para un motor de CD a través de un convertidor reductor, el cual sigue una trayectoria de referencia suave diseñada mediante un polinomio de interpolación Bézier. El sistema reduce los picos súbitos de voltaje y c [...] orriente en el circuito de armadura del motor durante el arranque. El cálculo del control de velocidad se obtiene de una salida F llamada salida plana (calculada a través de la matriz de controlabilidad de Kalman). Este control se basa en la retroalimentación de todos los estados reescritos en términos de la salida plana y de sus derivadas sucesivas para el seguimiento de la trayectoria. Con la ayuda de la técnica de ubicación de polos es posible sintonizar adecuadamente el controlador en lazo cerrado. La efectividad del sistema se verifica experimentalmente mediante una plataforma que está compuesta por el convertidor reductor-motor CD y un modulador PWM. Abstract in english This article presents the design and implementation of a speed controller for a DC motor through a buck converter, which tracks a smooth reference trajectory designed by a Bezier polynomial interpolation. The system reduces voltage and current sudden peaks in the armature circuit of the motor during [...] the start. The calculation of the speed control is obtained from an output F called flat output (calculated through the Kalman controllability matrix). This control is based on feedback from all states rewritten in terms of the flat output and its successive derivatives for tracking the trajectory. With the aid of the pole placement technique it is possible to properly tune the controller in closed loop. The effectiveness of the system is verified experimentally by means of a platform that consists of the DC motor-buck converter and a PWM modulator.
DEFF Research Database (Denmark)
Tang, Yi; Zhu, Dexuan
2015-01-01
This paper presents a three-level quasi-two-stage single-phase power factor correction (PFC) converter that has flexible output voltage and improved conversion efficiency. The proposed PFC converter features sinusoidal input current, three-level output characteristic, and a wide range of output dc voltages, and it will be very suitable for high-power applications where the output voltage can be either lower or higher than the peak ac input voltage, e.g., plug-in hybrid electric vehicle charging systems. Moreover, the involved dc/dc buck conversion stage may only need to process partial input power rather than full scale of the input power, and therefore the system overall efficiency can be much improved. Through proper control of the buck converter, it is also possible to mitigate the double-line frequency ripple power that is inherent in a single-phase ac/dc system, and the resulting load end voltage will be fairly constant. The dynamic response of this regulation loop is also very fast and the system is therefore insensitive to external disturbances. Both simulation and experimental results are presented to show the effectiveness of this converter as well as its efficiency improvement against a conventional two-stage solution.
Directory of Open Access Journals (Sweden)
I Wayan Arta Wijaya
2012-05-01
Full Text Available Pengubah daya DC-DC topologi boost dapat menghasilkan tegangan yang lebih tinggi dari tegangan input dengan riak (ripple yang kecil dan efisiensi yang cukup tinggi. Nilai dari sebuah induktansi dan kapasitansi dari pengubah daya DC-DC dengan menggunakan topologi boost dioptimalkan menggunakan analisa transien. Fungsi ini diatur berdasarkan pada analisa dari pengubah daya selama kondisi transien. Nilai induktansi dan kapasitansi yang telah dioptimalkan dengan perhitungan dibandingkan dalam simulasi pada pengubah daya DC-DC dan hasilnya akan dibuktikan dengan menggunakan hasil percobaan. Nilai optimal untuk kapasitor dan induktor pada frekuensi 666,7 Hz, siklus kerja (duty cycle 66,7 %, resistansi output 36 Î dan tegangan input 12 volt adalah 1038 Î¼F dan 11,9 mH
Bidirectional converter interface for a battery energy storage test bench
DEFF Research Database (Denmark)
Trintis, Ionut; Thomas, Stephan; Blank, Tobias; Roggendorf, Christoph; Munk-Nielsen, Stig; Teodorescu, Remus
This paper presents the bidirectional converter interface for a 6 kV battery energy storage test bench. The power electronic interface consists a two stage converter topology having a low voltage dc-ac grid connected converter and a new dual active bridge dc-dc converter with high transformation...... ratio. The dc-dc converter controls the battery charge/discharge current while the grid converter controls the common dc-link voltage and the grid current. The applied control structures and the hardware implementation of both converters are presented, together with their interaction. Experimental...
High Efficiency Reversible Fuel Cell Power Converter
DEFF Research Database (Denmark)
Pittini, Riccardo
traditional unidirectional fuel cell, bidirectional fuel cells have increased operating voltage and current ranges. These characteristics increase the stresses on dc-dc and dc-ac converters in the electrical system, which require proper design and advanced optimization. This work is part of the PhD project...... entitled "High Efficiency Reversible Fuel Cell Power Converter" and it presents the design of a high efficiency dc-dc converter developed and optimized for bidirectional fuel cell applications. First, a brief overview of fuel cell and energy storage technologies is presented. Different system topologies as...... well as different dc-ac and dc-dc converter topologies are presented and analyzed. A new ac-dc topology for high efficiency data center applications is proposed and an efficiency characterization based on the fuel cell stack I-V characteristic curve is presented. The second part discusses the main...
Efficient Power Conversion in Common Active Clamp for Interleaved Dc-Dc Boost
V. Rathinavel Subramaniam; C.Nallasivam
2014-01-01
This project presents a high-efficiency and high-step-up non isolated interleaved dc to dc converter with a common active-clamp circuit. In the presented converter, the coupled-inductor boost converters are interleaved. A boost converter is used to clamp the voltage stresses of all the switches in the interleaved converters, caused by the leakage inductances present in the practical coupled inductors, to a low voltage level. The leakage energies of the inter-leaved converters ...
Asymptotic Tracking with DC-to-DC Bilinear Power Converters
Olm i Miras, Josep M.
2004-01-01
Avui en dia la conversió DC-AC té una important aplicació pràctica en el camp dels sistemes de potència ininterrompuda (SPI). Els convertidors commutats bàsics (el buck, lineal, i el boost i el buck-boost, no lineals) presenten una estructura molt simple, i al llarg dels últims quinze anys s'ha estudiat la possibilitat d'usar-los en esquemes de conversió DC-AC. L'objectiu de la tesi és aconseguir que els convertidors DC-DC de potència bàsics puguin seguir referències alternes mitjançant el vo...
Power Converters Secure Electronics in Harsh Environments
2013-01-01
In order to harden power converters for the rigors of space, NASA awarded multiple SBIR contracts to Blacksburg, Virginia-based VPT Inc. The resulting hybrid DC-DC converters have proven valuable in aerospace applications, and as a result the company has generated millions in revenue from the product line and created four high-tech jobs to handle production.