Hybrid posicast controller for a DC-DC buck converter
Kaithamalai Udhayakumar; Ponnusamy Lakshmi; Kandasamy Boobal
2008-01-01
A new Posicast compensated hybrid controller for the DC-DC Buck converter is investigated. Posicast is a feed forward compensator, which eliminates the overshoot in the step response of a lightly damped system. However, the traditional method is sensitive to variations in natural frequency. The new method described here reduces this undesirable sensitivity by using Posicast within the feedback loop. Design of the Posicast function is independent of computational delay. The new controller resu...
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
Lapčević Vladimir
2014-01-01
In this paper is presented charger for NiMH battery types AA. Charger is realized by Buck DC/DC converter and microcontroller. Microcontroller controls the work of Buck DC/DC converter by pulse width modulation and by measuring the current of battery charging. The current of charging is held constant by power electronics, and the time of charging is set by the user dependent of capacity of the battery. Standard battery chargers enable the recharge of NiMH b...
DEFF Research Database (Denmark)
Yang, Xi-jun; Qu, Hao; Yao, Chen; Zhang, Ning-yun; Tang, Hou-jun; Chen, Quan; Blaabjerg, Frede
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...
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.
Design of a PEM Fuel Cell Simulator Based on DC-DC Buck Converter
Georgi Georgievski; Goce L. Arsov
2010-01-01
Modeling of fuel cells is getting more and more important as power fuel cell stacks being available and have to be integrated into real power systems. This paper presents a novel circuit simulator for a PEM fuel cell that can be used to design fuel cell based systems. The simulator is consisted of a DC-DC buck converter driven by PIC 16F877 microcontroller. The proposed circuit can be used in design and analysis of fuel cell power systems.
A New Zero Voltage Switching Buck-Boost Type DC-DC Converter
Directory of Open Access Journals (Sweden)
Majid Delshad
2010-03-01
Full Text Available In this paper, a new zero voltage switching isolated buck-boost DC-DC converter with active clamp circuit is proposed. The active clamp circuit in this converter not only absorbs voltage spikes across the main switch but also provides soft switching conditions for all switches. All switches are PWM controlled which simplifies the control implementation. One of the main advantages of this converter is the that it operating can operate at high power levels while soft switching conditions exist in both buck and boost modes of converter operation. Since this converter can operate over a wide input voltage range, it can be employed in power factor correction. The experimental results obtained from a 150W prototype circuit operating at 100KHz are presented to confirm the integrity of the proposed circuit.
Directory of Open Access Journals (Sweden)
Dhananjay Choudhary
2014-08-01
Full Text Available The two basic topologies of switch mode DC-DC converters (Buck and Boost are analyzed with a view of their use in PV (photovoltaic systems, as the photovoltaic generator exhibits non-linear characteristics due to the change in environmental condition and load variation. As the efficiency of PV panels is low it becomes mandatory to extract maximum power from the PV panel at a given period of time. Several MPPT algorithms with different types of converters are being proposed for extracting maximum power from the PV panel. It is found that the nature of load plays an important role in the choice of topology. This paper investigates the implementation issues of Incremental Conductance method with Buck and Boost Converters. Mathematical analysis and desirable steady-state operating point of the converters are derived to give satisfactory maximum power point tracking operation.
DEFF Research Database (Denmark)
Pelan, Ovidiu; Cornea, Octavian; Muntean, Nicolae;
2014-01-01
This paper presents and discusses design considerations and efficiency investigation of a conventional step-down and a hybrid switched-capacitor DC-DC converter. Three MOSFETs with low on-resistance have been tested for each converter in order to find the most adequate switch for this application....... The experimental results and comparative efficiency graphs were obtained with a 1kW laboratory prototype dedicated for a 42/14V dual voltage automotive system....
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.
A low noise high efficiency buck DC-DC converter with sigma-delta modulation
International Nuclear Information System (INIS)
Some research efforts to improve the efficiency and noise performance of buck DC-DC converters are explored. A carefully designed power MOSFET driver, including a dead time controller, discontinuous current mode (DCM) controller and gate width controller, is proposed to improve efficiency. Instead of PWM modulation, sigma-delta modulation is introduced into the feedback loop of the converter to move out the clock-referred harmonic spike. The proposed converter has been designed and fabricated by a 0.35 μm CMOS process. Measured results show that the peak efficiency of the converter can reach 93% and sigma-delta modulation suppresses the harmonic spike by 30 dB over PWM modulation. (semiconductor integrated circuits)
Silva-Ortigoza, R.; C. Márquez-Sánchez; F. Carrizosa-Corral; M. Antonio-Cruz; J. M. Alba-Martínez; Saldaña-González, G.
2014-01-01
This paper presents a hierarchical controller that carries out the angular velocity trajectory tracking task for a DC motor driven by a DC/DC Buck converter. The high level control is related to the DC motor and the low level control is dedicated to the DC/DC Buck converter; both controls are designed via differential flatness. The high level control provides a desired voltage profile for the DC motor to achieve the tracking of a desired angular velocity trajectory. Then, a low level control ...
Integrated Circuit of CMOS DC-DC Buck Converter with Differential Active Inductor
Directory of Open Access Journals (Sweden)
Kaoutar Elbakkar
2011-11-01
Full Text Available In this paper, we propose a new design of DC-DC buck converter (BC, which the spiral inductor is replaced by a differential gyrator with capacitor load (gyrator-C implemented in 0.18um CMOS process. The gyrator-C transforms the capacitor load (which is the parasitic capacitor of MOSFETS to differential active inductor DAI. The low-Q value of DAI at switching frequency of converter (few hundred kHz is boosted by adding a negative impedance converter (NIC. The transistor parameters of DAI and NIC can be properly chosen to achieve the desirable value of equivalent inductance L (few tens H, and the maximum-Q value at the switching frequency, and thus the efficiency of converter is improved. Experimental results show that the converter supplied with an input voltage of 1V, provides an output voltage of 0.74V and output ripple voltage of 10mV at 155 kHz and Q-value is maximum (#8776;4226 at this frequency.
An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters
Directory of Open Access Journals (Sweden)
Run Min
2014-05-01
Full Text Available In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally.
An optimal current observer for predictive current controlled buck DC-DC converters.
Min, Run; Chen, Chen; Zhang, Xiaodong; Zou, Xuecheng; Tong, Qiaoling; Zhang, Qiao
2014-01-01
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In this paper, an optimal current observer is proposed. It achieves the highest observation accuracy by compensating for all the known parasitic parameters. By employing the optimal current observer-based predictive current controller, a buck converter is implemented. The converter has a convergently and accurately observed inductor current, and shows preferable transient response than the conventional voltage mode controlled converter. Besides, costs, power loss and size are minimized since the strategy requires no additional hardware for current sensing. The effectiveness of the proposed optimal current observer is demonstrated experimentally. PMID:24854061
Directory of Open Access Journals (Sweden)
Ahteshamul Haque
2016-02-01
Full Text Available The energy crisis concern leads to look for alternate source of energy. Solar energy is considered as most reliable among the all renewable energy sources. Solar PV (Photovoltaic is used to convert solar energy into electric energy. The efficiency of solar PV is very low and its characteristic is nonlinear. To overcome these drawbacks a technique known as maximum power point tracking is used. This algorithm is implemented in the control circuit of DC – DC converter. The objective of this paper is to evaluate the MPPT (Maximum Power Point Tracking with buck DC-DC converter under load varying conditions. The simulation work is done using PSIM simulation software.
An Optimal Current Observer for Predictive Current Controlled Buck DC-DC Converters
Run Min; Chen Chen; Xiaodong Zhang; Xuecheng Zou; Qiaoling Tong; Qiao Zhang
2014-01-01
In digital current mode controlled DC-DC converters, conventional current sensors might not provide isolation at a minimized price, power loss and size. Therefore, a current observer which can be realized based on the digital circuit itself, is a possible substitute. However, the observed current may diverge due to the parasitic resistors and the forward conduction voltage of the diode. Moreover, the divergence of the observed current will cause steady state errors in the output voltage. In t...
Nonlinear state-feedback with disturbances estimation for DC-DC Buck converter
Fall, Mamadou Lamine; Gehan, Olivier; Pigeon, Eric; Pouliquen, Mathieu; M'Saad, Mohammed
2012-01-01
Abstract--The aim of this paper is to present new results on the Buck converter control. The behaviour of the buck converter is described by the well-known average model and the control strategy is based on a double integral high gain control law including an estimation of current load. This control scheme rejects efficiently the disturbances introduced by the battery dynamics that depends on both the coil current and its charge level. Of particular interest, this nonlinear control algorithm ...
Preliminary Design of a PEM Fuel Cell Simulator Based on Digitally Controlled DC-DC Buck Converter
Goce L. Arsov; Georgi Georgievski
2009-01-01
Modeling of fuel cells is getting more and more important as power fuel cell stacks being available and have to be integrated into real power systems. This paper presents a novel circuit model for a PEM fuel cell that can be used to design fuel cell simulator. The model is consisted of a DC-DC buck converter driven by PIC 16F877 microcontroller. The model can be used in design and analysis of fuel cell power systems by simulation or by using practically realized simulator.
Preliminary Design of a PEM Fuel Cell Simulator Based on Digitally Controlled DC-DC Buck Converter
Directory of Open Access Journals (Sweden)
Goce L. Arsov
2009-06-01
Full Text Available Modeling of fuel cells is getting more and more important as power fuel cell stacks being available and have to be integrated into real power systems. This paper presents a novel circuit model for a PEM fuel cell that can be used to design fuel cell simulator. The model is consisted of a DC-DC buck converter driven by PIC 16F877 microcontroller. The model can be used in design and analysis of fuel cell power systems by simulation or by using practically realized simulator.
Directory of Open Access Journals (Sweden)
Benlafkih Abdessamad
2013-01-01
Full Text Available this paper presents comparative performance between Analog and digital controller on DC/DC buck-boost converter four switch. The design of power electronic converter circuit with the use of closed loop scheme needs modeling and then simulating the converter using the modeled equations. This can easily be done with the help of state equations and MATLAB/SIMULINK as a tool for simulation of those state equations. DC/DC Buckboost converter in this study is operated in buck (step-down and boost (step-up modes.
Benlafkih Abdessamad; Krit Salah-Ddine; Chafik Elidrissi Mohamed
2013-01-01
this paper presents comparative performance between Analog and digital controller on DC/DC buck-boost converter four switch. The design of power electronic converter circuit with the use of closed loop scheme needs modeling and then simulating the converter using the modeled equations. This can easily be done with the help of state equations and MATLAB/SIMULINK as a tool for simulation of those state equations. DC/DC Buckboost converter in this study is operated in buck (step-down) and boost ...
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 μm 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)
Optimal Control with Complete Load-Decoupled Design for the Buck DC-DC Switching Converter
Institute of Scientific and Technical Information of China (English)
Fei-Hu; Hsieh; Yau-Tarng; Juang
2002-01-01
This paper describes a new controller design procedure and turning method for the buck PWM DCDCswitching converter taking into consideration the equivalent series resistance of components. First, the linearoptimal feedback is designed by the LQR approach. Then the designed control law is implemented by aphase-lag lead controller incorporated with a complete load-decoupled PD compensator. The phase-lag lead controlleris tuned to achieve the optimal design based on the output error voltage directly, instead of using an estimator.With the proposed PD compensator, the converter is robust with respect to the load changes and parameterperturbations. We also provide the conditions for the robust stability assurance of the closed-loop system.
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 Multiport Isolated DC-DC Converter
Tran, Yan-Kim; Dujic, Drazen
2016-01-01
This paper presents a multi-port isolated DC-DC converter for DC applications. A three-port structure is presented, characterized with full bidirectional power flow and simple control. Galvanic isolation is achieved by means of a multi-winding medium frequency transformer which is a part of a resonant LLC converter. To provide controllable power exchange with external DC ports, two out of three ports are equipped with additional bidirectional buck/boost stages. They serve to provide active po...
Generalization of zad strategy: an application to a dc-dc buck converter
ANGULO GARCIA, FABIOLA; Olivar Tost, Gerard; Osorio Londoño, Gustavo Adolfo
2011-01-01
The Zero Average Dynamics (ZAD) strategy has been reported in the last decade as an alternative for controlling power converters. This technique has the advantage of guaranteeing fi xed frequency switching. However, the stability of the controller is highly dependent on the load value, and when the stability is lost, the fi xed frequency switching is lost too. In this paper we generalize ZAD strategy using the probabilities framework through the expectation operator. Thus, we recover class...
Mixed-Signal PI Controller in Current-Mode DC-DC Buck Converter for Automotive Applications
Moursy, Yasser; Khalil, Raouf; Lecce, Sergio; Poletto, Vanni; Iskander, Ramy; Louërat, Marie-Minerve
2016-01-01
International audience This paper proposes a fully-integrated solution for the PI compensation circuits in current-mode DC-DC converters used in automotive applications. In such applications, the switching frequencies are low and hence conventional PI compensation circuits employ large capacitors. The proposed analog/mixed-signal PI comprises an analog proportional amplifier and a digital integrator. The analog proportional amplifier provides the required response time and maintains system...
George, Libin; Gargiulo, Gaetano Dario; Lehmann, Torsten; Hamilton, Tara Julia
2016-06-01
This paper presents the design of a reconfigurable buck-boost switched-capacitor DC-DC converter suitable for use in a wide range of biomedical implants. The proposed converter has an extremely small footprint and uses a novel control method that allows coarse and fine control of the output voltage. The converter uses adaptive gain control, discrete frequency scaling and pulse-skipping schemes to regulate the power delivered to a range of output voltages and loads. Adaptive gain control is used to implement variable switching gain ratios from a reconfigurable power stage and thereby make coarse steps in output voltage. A discrete frequency scaling controller makes discrete changes in switching frequency to vary the power delivered to the load and perform fine tuning when the output voltage is within 10% of the target output voltage. The control architecture is predominately digital and it has been implemented as part of a fully-integrated switched-capacitor converter design using a standard bulk CMOS 0.18 μm process. Measured results show that the converter has an output voltage range of 1.0 to 2.2 V, can deliver up to 7.5 mW of load power and efficiency up to 75% using an active area of only 0.04 mm (2), which is significantly smaller than that of other designs. This low-area, low-complexity reconfigurable power converter can support low-power circuits in biomedical implant applications. PMID:26600247
Hybrid battery with bi-directional DC/DC converter
DUDRIK Jaroslav; OLEJAR Martin; BERES Tomáš
2010-01-01
Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.
Hybrid battery with bi-directional DC/DC converter
Directory of Open Access Journals (Sweden)
DUDRIK Jaroslav
2010-05-01
Full Text Available Bi-directional buck-boost DC/DC converterfor hybrid battery is described in this paper. The firstpart of the paper is aimed at concept of hybrid battery;main advance compared to conventional accumulatoris explained there. Control circuit with UC3637 andpower circuit of the converter are described in thesecond part of the paper. Experimental results frommeasuring of converter are mentioned in the last part.
Energy saving dc-dc converter circuit
International Nuclear Information System (INIS)
An energy saving dc-dc converter circuit is disclosed having two energy efficient means which operate in tandem, an energy conserving means and a voltage doubling means. These energy efficient means are applied in combination with elements commonly found in dc-dc converter circuits, namely an ac voltage generator, a transformer for stepping up the generated ac voltage, and means for storing the converted dc voltage. The energy conserving means is connected to the dc voltage storage means. It comprises a resettable inhibit circuit which cuts off the provision of dc voltage for conversion for a predetermined interval when the output of the converter exceeds a predetermined level. The voltage doubling means is reponsive to outputs of the inhibit circuit of the energy conserving means and the ac voltage generator. It provides a phase inverted waveform of the generated ac voltage on one of two leads to the ac voltage step-up transformer
A resonant dc-dc power converter assembly
DEFF Research Database (Denmark)
2015-01-01
The present invention relates to a resonant DC-DC power converter assembly comprising a first resonant DC-DC power converter and a second resonant DC-DC power converter having identical circuit topologies. A first inductor of the first resonant DC-DC power converter and a second inductor of the...... second resonant DC-DC power converter are configured for magnetically coupling the first and second resonant DC-DC power converters to each other to forcing substantially 180 degrees phase shift, or forcing substantially 0 degree phase shift, between corresponding resonant voltage waveforms of the first...... and second resonant DC-DC power converters. The first and second inductors are corresponding components of the first and second resonant DC-DC power converters....
Radiation-Tolerant DC-DC Converters
Skutt, Glenn; Sable, Dan; Leslie, Leonard; Graham, Shawn
2012-01-01
A document discusses power converters suitable for space use that meet the DSCC MIL-PRF-38534 Appendix G radiation hardness level P classification. A method for qualifying commercially produced electronic parts for DC-DC converters per the Defense Supply Center Columbus (DSCC) radiation hardened assurance requirements was developed. Development and compliance testing of standard hybrid converters suitable for space use were completed for missions with total dose radiation requirements of up to 30 kRad. This innovation provides the same overall performance as standard hybrid converters, but includes assurance of radiation- tolerant design through components and design compliance testing. This availability of design-certified radiation-tolerant converters can significantly reduce total cost and delivery time for power converters for space applications that fit the appropriate DSCC classification (30 kRad).
Energy Factor and Mathematical Modeling for Power DC/DC Converters
Institute of Scientific and Technical Information of China (English)
Fang Lin LUO; Hong YE
2004-01-01
Mathematical modelling for power DC/DC converters is a historical problem accompanying DC/DC conversion technology since 1940's. The traditional mathematical modelling is not available for complex structure converters since the differential equation order increases very high. We have to search other way to establish mathematical modelling for power DC/DC converters. We have theoretically defined a new concept - Energy Factor (EF) in this paper and researched the relations between EF and the mathematical modelling for power DC/DC converters. EF is a new concept in power DC/DC conversion technology, which thoroughly differs from the traditional concepts such as power factor (PF), power transfer efficiency (η), total harmonic distortion (THD) and ripple factor (RF). EF and the subsequential EFv (and EFvD ) can illustrate the system stability, reference response and interference recovery. This investigation is very helpful for system design and DC/DC converters characteristics foreseeing. Two DC/DC converters: Buck converter and Super-Lift Luo-Converter as the samples are analysed in this paper to demonstrate the applications of EF, EFv (and EFvD), PE,SE, VE (and VED ), time constant τ and damping time constant τd .
High Efficiency Interleaved Bi-Directional ZVS DC-DC Converter
DEFF Research Database (Denmark)
Zafar Ullah Khan, M.; Mohsin Naveed, M.; Hussain, Dil Muhammad Akbar
2013-01-01
A High Efficiency Interleaved Bi-Directional ZVS DC-DC converter is presented in this paper. This converter can be operated in both buck and boost mode. CoolMOS is used as a power device to achieve low conduction losses and fast turn off. The value of inductance is selected such that the CoolMOS ...
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
Institute of Scientific and Technical Information of China (English)
常昌远; 陈瑶; 黄金峰; 王青
2012-01-01
A simplified fuzzy control algorithm used for digitally controlled DC-DC converters, the single input fuzzy control algorithm, is proposed. In this algorithm, the signed distance method is introduced to simplify the two inputs in the conventional fuzzy control algorithm to a single input, making the number of the corresponding fuzzy rules significantly reduced. On this basis, the single input fuzzy controller is designed by the field-programmable gate array (FPGA), and the final verification is performed. The experimental results show that for the Buck DC-DC switching converter, when the input voltage is 2.7 to 3.5 V and the output voltage is 0. 8 to 1.5 V, the set-up time is less than 150 ms and the steady-state error is less than 10 mV. Compared with the conventional fuzzy controller, the single input fuzzy controller has simpler hardware implementation in design, regulation and implementation. Therefore, it may be widely used in digitally controlled DC-DC converters.%提出了一种简化的用于数字控制DC-DC变换器的模糊控制算法——单输入模糊控制算法.通过在算法中引入符号距离法,将常规模糊控制算法中的2个输入简化为单个输入,从而使相应的模糊规则条数明显减少.在此基础上,采用FPGA设计了单输入模糊控制器,并进行了系统验证.测试结果表明,在输入电压为2.7～3.5V、输出电压为0.8～1.5V的Buck型DC-DC开关变换器中,系统的建立时间小于150 ms,稳态误差小于10 mV.与常规模糊控制器相比,这种单输入模糊控制器具有设计、调节和硬件实现简单等优势,因而有望在数字控制DC-DC变换器中得到广泛应用.
Institute of Scientific and Technical Information of China (English)
孙大鹰; 徐申; 孙伟锋; 陆生礼
2014-01-01
为了提高数字DC-DC变换器的瞬态响应性能，设计了一种基于数字预测控制方法的模糊PID控制器。该控制器根据Buck型DC-DC变换器的电路结构，准确预测单个开关周期或多个开关周期后的负载电压和电感电流，以克服环路时延对系统瞬态响应的影响；同时，在基本PID控制基础上引入模糊控制，实时在线调整PID控制参数，以克服变换器的非线性特性对瞬态能力的影响。所设计数字控制器经FPGA验证，结果表明，与基本PID控制相比，所设计数字预测模糊PID控制器能有效提高变换器的瞬态响应能力，变换器的瞬态响应时间缩短1/3，电压超调量小于5％。%To improve the transient response of digital DC-DC converter,a digital fuzzy proportion-al-integral-derivative (PID)controller with a prediction algorithm is proposed.In the digital control-ler,the output voltage and inductance current after one cycle or multiple cycles are predicted accu-rately based on the circuit structure of Buck DC-DC converter,which overcomes the influence of loop time delay on the transient response.Meanwhile,fuzzy control is introduced in the basic PID control to overcome the influence of the nonlinear characteristics of converter on the transient re-sponse through the real-time online regulation of PID control parameters.The proposed digital con-troller is implemented by the field programmable gate array (FPGA ).The results of verification show that the proposed controller can effectively improve the transient response of converter com-pared with basic PID control.The transient response time of converter can decrease by one third and the voltage overshoot is less than 5%.
Study on stability of the voltage-mode DC-DC converters
International Nuclear Information System (INIS)
Stroboscopic maps for voltage-mode converters in the continuous conduction mode (CCM) are build up. The stability of one-periodic point is analyzed together with eigenvalues of Jacobian matrix of discrete-maps. The voltage-mode buck converter is taken as an example, and the results of theoretical analysis and numerical simulation coincide with each other, which shows that the stability analysis of the DC-DC converters is feasible using the discrete-map model. (authors)
Implementation of FPGA based Digital Controller for Controlling Chaos in DC/DC converters
RANJAN Vanaja; LOGAMANI Premalatha
2010-01-01
This paper analyzes the subharmonics andchaos generated in closed loop pulse width modulatedDC/DC buck converter and suggests the implementationof Digital controller based on time delayed selfcontrolling feedback concept for stabilizing the chaosgenerated in such converter. FPGA based digitalcontroller is designed and implemented for controllingthe chaotic oscillations of nonlinear switching converters.An experimental FPGA prototype and an applicationspecific IC that employ new controller arc...
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.
On and off controlled resonant dc-dc power converter
DEFF Research Database (Denmark)
2015-01-01
The present invention relates to a resonant DC-DC power converter comprising an input side circuit comprising a positive and a negative input terminal for receipt of an input voltage or current and an output side circuit comprising positive and negative output terminals for supply of a converter...... output voltage and connection to a converter load. The resonant DC-DC power converter further comprises a rectification circuit connected between an output of a resonant network and the output side circuit. The resonant network is configured for alternatingly being charged from the input voltage or...... current and discharged through the rectification circuit by a first controllable switch arrangement in accordance with a first switch control signal. A second controllable switch arrangement of the resonant DC-DC power converter is configured to select a first impedance characteristic of the resonant...
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.
A Novel FPSM Controller for DC-DC Switching Converters
Institute of Scientific and Technical Information of China (English)
Yong Feng; Shun-Ping Wang; Ping Luo; Quan-Ming Niu; Zhao-Ji Li
2007-01-01
This paper presents a novel fuzzy pulse skip modulation (FPSM) controller for switching direct current to direct current (DC-DC) converters based on fuzzy ratiocination modeling approach. Owing to the optimal consideration during the design and the nonlinear characteristics of the controller, improved dynamic responses of the FPSM controller can be achieved over conventional controllers. Compared with conventional proportion integral derivative (PID) control, FPSM control has 60% lower overshoot and 10% lower setting time under the same input voltage and output load change. The presented approach is general and can be applied to other types of DC-DC converters.
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 Technique for Hybrid DC/DC Converters
Wang, Bright L.
2011-01-01
Oscillation or instability is a situation that must be avoided for reliable hybrid DC/DC converters. A real-time electronics measurement technique was developed to detect catastrophic oscillations at early stages for hybrid DC/DC converters. It is capable of identifying low-level oscillation and determining the degree of the oscillation at a unique frequency for every individual model of the converters without disturbing their normal operations. This technique is specially developed for space-used hybrid DC/DC converters, but it is also suitable for most of commercial and military switching-mode power supplies. This is a weak-electronic-signal detection technique to detect hybrid DC/DC converter oscillation presented as a specific noise signal at power input pins. It is based on principles of feedback control loop oscillation and RF signal modulations, and is realized by using signal power spectral analysis. On the power spectrum, a channel power amplitude at characteristic frequency (CPcf) and a channel power amplitude at switching frequency (CPsw) are chosen as oscillation level indicators. If the converter is stable, the CPcf is a very small pulse and the CPsw is a larger, clear, single pulse. At early stage of oscillation, the CPcf increases to a certain level and the CPsw shows a small pair of sideband pulses around it. If the converter oscillates, the CPcf reaches to a higher level and the CPsw shows more high-level sideband pulses. A comprehensive stability index (CSI) is adopted as a quantitative measure to accurately assign a degree of stability to a specific DC/DC converter. The CSI is a ratio of normal and abnormal power spectral density, and can be calculated using specified and measured CPcf and CPsw data. The novel and unique feature of this technique is the use of power channel amplitudes at characteristic frequency and switching frequency to evaluate stability and identify oscillations at an early stage without interfering with a DC/DC converter s
Hysteretic Current Controlled Zvs Dc/Dc Converter For Automobile
DEFF Research Database (Denmark)
Cernat, M.; Scortarul, P.; Tanase, A.;
2007-01-01
A novel bi-directional dc-dc converter with ZVS and interleaving for dual voltage systems in automobiles is presented. A variable frequency extended band hysteretic current control method is proposed. In comparison with classical fixed frequency current control PWM, the reverse polarity peak...
Soft Commutated Three-Phase Dc-Dc Converter
Silpa.P.T; Rajeenamol P.T
2014-01-01
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-p...
Analysis and Experimental Study of Proportional-Integral Sliding Mode Control for DC/DC Converter
Institute of Scientific and Technical Information of China (English)
ZHANG Li; QIU Shui-sheng
2005-01-01
DC/DC converter using the proportional-integral (PI) sliding mode control (SMC) scheme is investigated, including the selection of the switching surface, the proof of the reaching condition and the existence condition of sliding motion. The sliding regime and the local stability are given. The implementation of the PI SMC is simpler than other SMC schemes and the steady-state error is eliminated. A prototype based on Buck converter is built up. The experimental results show that the dynamic performance and robustness to the parameter variations and external disturbances are improved.
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.
Very High Frequency Half Bridge DC/DC Converter
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
2014-01-01
This paper presents the first, off chip, class DE (resonant half bridge) converter working in the Very High Frequency (VHF) range. The benefits of using half bridge circuits both in the inverter and rectifier part of a VHF resonant dc/dc converter are analyzed and design equations for all...... components in the power stage are given. The circuit has been simulated to verify the accuracy of the presented equations and an efficiency of 89% has been shown. A prototype has been implemented with self-oscillating resonant gate drives driving the switches. The prototype has been used to drive an LED...
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...
Discrete prediction controller for DC-DC converter - doi: 10.4025/actascitechnol.v36i1.18770
Rengamani Shenbagalakshmi; Thangaswamy Sree Renga Raja
2014-01-01
A discrete controller is designed for low power dc-dc switched mode power supplies. The approach is based on time domain and the control loop continuously and concurrently tunes the compensator parameters to meet the converter specifications. A digital state feedback control combined with the load estimator provides a complete compensation, which further improves the dynamic performance of the closed loop system. Simulation of digitally controlled Buck converter is performed with MATLAB/Simul...
qZS-Based Soft-Switching DC/DC Converter with a Series Resonant LC Circuit
Vinnikov, D; Zaķis, J; Liivik, L; Raņķis, I
2013-01-01
This paper discusses further modifications of the recent popular qZS-based DC/DC converter design by the introduction of the resonant LC circuit in series to the primary winding of the isolation transformer. The primary aim is to achieve the zero voltage and zero current switching of transistors. As an additional benefit of the resonant LC circuit, the converter is able to perform the voltage buck function simply by changing the switching frequency of the transistors. The control principle of...
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.
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.
DEFF Research Database (Denmark)
2015-01-01
being charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier in accordance with a switch control signal to produce the converter output voltage. The step-up DC-DC power converter comprises an electrical short-circuit connection across the galvanic...... capacitor coupled between the positive and negative input terminals and the secondary side circuit comprises an output capacitor chargeable to a converter output voltage between a first positive electrode and a second negative electrode. A switched energy storage network is configured for alternatingly...... isolation barrier connecting, in a first case, the second negative electrode of the output capacitor to the positive input terminal of the primary side circuit or, in a second case, connecting the second positive electrode of the output capacitor to the negative input terminal of the primary side circuit...
RESONANT STEP-DOWN DC-DC POWER CONVERTERS
DEFF Research Database (Denmark)
2015-01-01
alternatingly being charged from the input voltage and discharged to the output capacitor through the galvanic isolation barrier by a semiconductor switch arrangement in accordance with a switch control signal to produce the converter output voltage. The resonant step-down DC-DC power converter comprises an...... electrical short-circuit connection across the galvanic isolation barrier connecting, in a first case, the second negative electrode of the output capacitor to the positive input terminal of the primary side circuit or, in a second case, connecting the second positive electrode of the output capacitor to the...... and an input capacitor coupled between the positive and negative input terminals and the secondary side circuit comprises an output capacitor chargeable to a converter output voltage between a first positive electrode and a second negative electrode. A resonant network is con- figured for...
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...
Digital Voltage Control of DC-DC Boost Converter
Directory of Open Access Journals (Sweden)
T. M. Swathy
2015-05-01
Full Text Available The need for digital control for faster communication between power stage module & system controllers is increased with requirement of load complexity. The requirements also include stability of power module with the parametric variation. This paper presents a digital control of a dc-dc boost converter under nominal parameter conditions. The system controller has been verified in both frequency response as well as MATLAB-Simulink under nominal & parametric varying condition. The modeling of converter has been illustrated using state-space averaging technique. Direct digital design method is equipped to design the controller in frequency response to yield constant load voltage. The characteristic of load voltage before & after parametric variation is shown.
A Comparison of Half Bridge & Full Bridge Isolated DC-DC Converters for Electrolysis Application
R.Samuel Rajesh Babu; Joseph Henry
2011-01-01
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...
Large step-down DC-DC converters with reduced current stress
International Nuclear Information System (INIS)
In this paper, several DC-DC converters with large voltage step-down ratios are introduced. A simple modification in the output section of the conventional buck and quadratic converters can effectively extend the duty-cycle range. Only two additional components (an inductor and diode) are necessary for extending the duty-cycle range. The topologies presented in this paper show an improvement in the duty-cycle (about 40%) over the conventional buck and quadratic converters. Consequently, they are well suited for extreme step-down voltage conversion ratio applications. With extended duty-cycle, the current stress on all components is reduced, leading to a significant improvement of the system losses. The principle of operation, theoretical analysis, and comparison of circuit performances with other step-down converters is discussed regarding voltage and current stress. Experimental results of one prototype rated 40-W and operating at 100 kHz are provided in this paper to verify the performance of this new family of converters. The efficiency of the proposed converters is higher than the quadratic converters
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.
Self-Stable Chaos Control of dc-dc Converter
Institute of Scientific and Technical Information of China (English)
LU Wei-Guo; ZHOU Luo-Wei; WU Jun-Ke
2009-01-01
A new concept related to self-stable chaos control is first put forward,and its theoretical basis and realization are presented from the frequency-domain perspective. With a new analogous-circuit realization of this control its applications in the voltage-mode Buck converter is discussed. The harmonic-balance method is applied to determine the control range of the control parameter.The experiment results given in the last part confirm the validity of the proposed control method.
A Family of Four Quadrant DC/DC Converters with Reduced Number of Components
DEFF Research Database (Denmark)
Mostaan, Ali; Soltani, Mohsen
2016-01-01
A family of four quadrant DC/DC converters is presented in this paper. Compare with existing four quadrant DC/DC converters that have been introduced in literature, the proposed converters have lower number of components. There are two bidirectional switches, two coupled inductors and one capacitor...
Design & Implementation of Zero Voltage Switching Buck Converter
A.Suresh Kumar; P.Krishna Reddy
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...
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 Zero-Voltage and Zero-Current Switching DC-DC Converters
Directory of Open Access Journals (Sweden)
Jaroslav Dudrik
2005-01-01
Full Text Available The paper presents principles and properties of the soft switching PWM DC-DC converters. The attention is focused mainly on high power applications and thus the full-bridge inverters are used in DC-DC converters. Considerations are also given to the control methods and principles of the switching and conduction losses reduction.
Multi-cell DC-DC converters : modelling, analysis and control
International Nuclear Information System (INIS)
This paper is devoted to modeling of a two-cell DC/DC buck converter, to the analysis of its behavior and to the design of control methods that yield to improve its performances. Various numerical simulations and dynamical aspects of this system are illustrated in the time domain and in the parameter space. Without control, the system may present many undesirable behaviors such as sub-harmonics and chaotic oscillations. The proposed controllers are able to widen the stability range of the system. Optimum values of parameters giving rise to fast response while maintaining stable periodic behavior are given in closed form. However, it is detected that in a certain region of the parameter space, the stabilized periodic orbit may coexist with a chaotic attractor. Boundary between basins of attraction are obtained by means of numerical simulations.
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.
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...
Discrete prediction controller for DC-DC converter - doi: 10.4025/actascitechnol.v36i1.18770
Directory of Open Access Journals (Sweden)
Rengamani Shenbagalakshmi
2014-01-01
Full Text Available A discrete controller is designed for low power dc-dc switched mode power supplies. The approach is based on time domain and the control loop continuously and concurrently tunes the compensator parameters to meet the converter specifications. A digital state feedback control combined with the load estimator provides a complete compensation, which further improves the dynamic performance of the closed loop system. Simulation of digitally controlled Buck converter is performed with MATLAB/Simulink. Experimental results are given to demonstrate the effectiveness of the controller using LabVIEW with a data acquisition card (model DAQ Pad - 6009.
Power efficiency improvement of a multi-oscillated current resonant type DC-DC converter
Sato, Tadahiko; Matsuo, Hirofumi; Ota, Hiroyuki; Ishizuka, Yoichi; Higashi, Nobuhiro
2009-01-01
This paper deals with an improvement of a power efficiency of a multi-oscillated current resonant type DC-DC converter. The current resonant type converter employs generally the pulse frequency modulation and its magnetizing inductance is set relatively low. For this reason, the magnetizing current through the converter causes a power loss under a light load. In order to solve this problem, a multi-oscillated current resonant type DC-DC converter has been proposed, and revealed the advantage ...
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
Directory of Open Access Journals (Sweden)
Sona P
2014-02-01
Full Text Available A high efficiency interleaved ZVS active clamped current fed dc-dc converter is proposed in this paper specially used for fuel cell applications. As the fuel cell output is very low we are in need of a step up dc-dc converter. Here a current fed dc-dc converter is used. Two current fed dc-dc converters are interleaved by connecting their inputs in parallel and outputs in series. With this proposed methodology input current ripples in the fuel cell stacks can be reduced and a regulated output voltage ripples can be obtained. The active clamping circuit used in this model absorbs the turn off voltage spikes hence low voltage devices with low on state resistance can be used.Voltage doubler circuits will give double the output voltage than normal with smaller transformer turns ratio and flexibility. The proposed method is simulated in MATLAB for verifying the accuracy of the proposed design.
Modular Power System Configured with Standard Product Hybrid DC-DC Converters Project
National Aeronautics and Space Administration — VPT proposes an innovative concept whereby complex NASA space power electronic systems can be configured using a small number of qualified hybrid DC-DC converter...
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...
A DC-DC Converter Efficiency Model for System Level Analysis in Ultra Low Power Applications
Benton H. Calhoun; Aatmesh Shrivastava
2013-01-01
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 induct...
Control of the DC-DC Converter used into Energy Generation System
International Nuclear Information System (INIS)
This paper presents an investigation of the DC-DC Converter controller used into Energy Generation System. The full bridge is used into an Energy Generation System (EGS) as second power interface between the energy source and the high DC bus. The simulation results show that the DC-DC Converter behavior can be improved using a well designed PI control surface. The used Simulink models for the EGS blocks and some design considerations are presented, too. (authors)
Novel current resonance DC-DC converter with voltage doubler rectifier for fuel cell system
Kato, Hisatsugu; Matsuo, Hirofumi; Kimura, Takayuki; Sakamoto, Yukitaka
2010-01-01
This paper deals with a novel composite rsonance DC-DC converter for low input voltage, large input current and high output voltsge with the voltage doubler rectifier. which i developed to appl y to the power conditioner of the fuel system. The proposed DC-DC cnverter has the current and voltage resonance fnctions to reduce the switching power loss. The primary and secondary sides of the converter are composed of the current resonant full bridge circuit, and voltage doubler, respectively. For...
High reliability DC/DC converter module for electronic boards equipped with FPGAs
Viganò, W.; Boccardi, A.; Zamantzas, C.
2015-01-01
The Beam Instrumentation Group at CERN is designing a new general-purpose VME carrier module utilising several PTH04T230W DC/DC converters. These off-the-shelf converters are built with unshielded inductors and need to be mounted on the printed circuit board as stand-alone components. Thus, reducing the global manageability and increasing the total cost of the carrier module. The new design aims to develop a module with better power dissipation, efficiency and reliability. In the future, it should be also possible to be directly integrated on the mainboard. For this reason, a Buck DC/DC converter has been implemented with the following main characteristics: input range from 3.0 V to 5.5 V; output range from 0.6 V to 3.3 V, settable by means of an external resistor; output current protection at 6 A; maximum output ripple ± 50 mVpp; switching frequency of 300KHz; short circuit protection; On/Off function; EMI reduction with frequency spread spectrum; soft-start function and thermal shutdown, in a 16 × 19 mm compact size. The selected buck controller is the TPS40303 integrated circuit and drives the CSD16321 power MOSFET, both from Texas Instruments. All selected components have been used at a minimum derating of 50% to reduce component stress and increase the reliability of this module. The selected inductors, i.e. Bourns SRP1055, are the main contributor for the high efficiency (95%), due to their very low equivalent series resistance. On the 4-layer PCB comprising all the components of this module, a snubber circuit, for further reduction of the output ripple due to the MOSFET ringing, can be mounted optionally. It is left as an option due to its effect on the total efficiency. The board layout has been optimized for maximum heat transfer and it can be used without active cooling. The board can maintain the maximum temperature on its surface, while at maximum current output, below 55°C at 25°C ambient temperature. An example of the electrical performance
High reliability DC/DC converter module for electronic boards equipped with FPGAs
International Nuclear Information System (INIS)
The Beam Instrumentation Group at CERN is designing a new general-purpose VME carrier module utilising several PTH04T230W DC/DC converters. These off-the-shelf converters are built with unshielded inductors and need to be mounted on the printed circuit board as stand-alone components. Thus, reducing the global manageability and increasing the total cost of the carrier module. The new design aims to develop a module with better power dissipation, efficiency and reliability. In the future, it should be also possible to be directly integrated on the mainboard. For this reason, a Buck DC/DC converter has been implemented with the following main characteristics: input range from 3.0 V to 5.5 V; output range from 0.6 V to 3.3 V, settable by means of an external resistor; output current protection at 6 A; maximum output ripple ± 50 mVpp; switching frequency of 300KHz; short circuit protection; On/Off function; EMI reduction with frequency spread spectrum; soft-start function and thermal shutdown, in a 16 × 19 mm compact size. The selected buck controller is the TPS40303 integrated circuit and drives the CSD16321 power MOSFET, both from Texas Instruments. All selected components have been used at a minimum derating of 50% to reduce component stress and increase the reliability of this module. The selected inductors, i.e. Bourns SRP1055, are the main contributor for the high efficiency (95%), due to their very low equivalent series resistance. On the 4-layer PCB comprising all the components of this module, a snubber circuit, for further reduction of the output ripple due to the MOSFET ringing, can be mounted optionally. It is left as an option due to its effect on the total efficiency. The board layout has been optimized for maximum heat transfer and it can be used without active cooling. The board can maintain the maximum temperature on its surface, while at maximum current output, below 55°C at 25°C ambient temperature. An example of the electrical performance
A digitally controlled PWM/PSM dual-mode DC/DC converter
Institute of Scientific and Technical Information of China (English)
Zhen Shaowei; Zhang Bo; Luo Ping; Hou Sijian; Ye Jingxin; Ma Xiao
2011-01-01
A digitally controlled pulse width modulation/pulse skip modulation (PWM/PSM) dual-mode buck DC/DC converter is proposed.Its operation mode can be automatically chosen as continuous conduction mode (CCM) or discontinuous conduction mode (DCM).The converter works in PSM at DCM and in 2 MHz PWM at CCM.Switching loss is reduced at a light load by skipping cycles.Thus high conversion efficiency is realized in a wide load current.The implementations of PWM control blocks,such as the ADC,the digital pulse width modulator (DPWM) and the loop compensator,and PSM control blocks are described in detail.The parameters of the loop compensator can be programmed for different external component values and switching frequencies,which is much more flexible than its analog rivals.The chip is manufactured in 0.13 μm CMOS technology and the chip area is 1.21 mm2.Experimental results show that the conversion efficiency is high,being 90% at 200 mA and 67% at 20 mA.Meanwhile,the measured load step response shows that the proposed dual-mode converter has good stability.
A digitally controlled PWM/PSM dual-mode DC/DC converter
International Nuclear Information System (INIS)
A digitally controlled pulse width modulation/pulse skip modulation (PWM/PSM) dual-mode buck DC/DC converter is proposed. Its operation mode can be automatically chosen as continuous conduction mode (CCM) or discontinuous conduction mode (DCM). The converter works in PSM at DCM and in 2 MHz PWM at CCM. Switching loss is reduced at a light load by skipping cycles. Thus high conversion efficiency is realized in a wide load current. The implementations of PWM control blocks, such as the ADC, the digital pulse width modulator (DPWM) and the loop compensator, and PSM control blocks are described in detail. The parameters of the loop compensator can be programmed for different external component values and switching frequencies, which is much more flexible than its analog rivals. The chip is manufactured in 0.13 μm CMOS technology and the chip area is 1.21 mm2. Experimental results show that the conversion efficiency is high, being 90% at 200 mA and 67% at 20 mA. Meanwhile, the measured load step response shows that the proposed dual-mode converter has good stability. (semiconductor integrated circuits)
Analysis and Controller Design of a Universal Bidirectional DC-DC Converter
Directory of Open Access Journals (Sweden)
Kou-Bin Liu
2016-06-01
Full Text Available In this paper, first the operating principles of a non-isolated universal bidirectional DC-DC converter are studied and analyzed. The presented power converter is capable of operating in all power transferring directions in buck/boost modes. Zero voltage switching can be achieved for all the power switches through proper modulation strategy design, therefore, the presented converter can achieve high efficiency. To further improve the efficiency, the relationship between the phase-shift angle and the overall system efficiency is analyzed in detail, an adaptive phase-shift (APS control method which determines the phase-shift value between gating signals according to the load level is then proposed. As the modulation strategy is a software-based solution, there is no requirement for additional circuits, therefore, it can be implemented easily and instability and noise susceptibility problems can be reduced. To validate the correctness and the effectiveness of the proposed method, a 300 W prototyping circuit is implemented and tested. A low cost dsPIC33FJ16GS502 digital signal controller is adopted in this paper to realize the power flow control, DC-bus voltage regulation and APS control. According to the experimental results, a 12.2% efficiency improvement at light load and 4.0% efficiency improvement at half load can be achieved.
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.
Test Results of Selected Commercial DC/DC Converters under Cryogenic Temperatures - A Digest
Patterson, Richard; Hammoud, Ahmad
2010-01-01
DC/DC converters are widely used in space power systems in the areas of power management and distribution, signal conditioning, and motor control. Design of DC/DC converters to survive cryogenic temperatures will improve the power system performance, simplify design, and reduce development and launch costs. In this work, the performance of nine COTS modular, low-tomedium power DC/DC converters was investigated under cryogenic temperatures. The converters were evaluated in terms of their output regulation, efficiency, and input and output currents. At a given temperature, these properties were obtained at various input voltages and at different load levels. A summary on the performance of the tested converters was given. More comprehensive testing and in-depth analysis of performance under long-term exposure to extreme temperatures are deemed necessary to establish the suitability of these and other devices for use in the harsh environment of space exploration missions.
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.
Very High Frequency Resonant DC/DC Converters for LED Lighting
DEFF Research Database (Denmark)
Madsen, Mickey Pierre; Knott, Arnold; Andersen, Michael A. E.
2013-01-01
This paper presents a very high frequency DC/DC converter for LED lighting. Several resonant topologies are compared and their usability discussed. At the end the resonant SEPIC converter is chosen based on the achievable power density and total bill of material. Simulations of a 51 MHz converter...
Novel bidirectional DC-DC converters based on the three-state switching cell
da Silva Júnior, José Carlos; Robles Balestero, Juan Paulo; Lessa Tofoli, Fernando
2016-05-01
It is well known that there is an increasing demand for bidirectional DC-DC converters for applications that range from renewable energy sources to electric vehicles. Within this context, this work proposes novel DC-DC converter topologies that use the three-state switching cell (3SSC), whose well-known advantages over conventional existing structures are ability to operate at high current levels, while current sharing is maintained by a high frequency transformer; reduction of cost and dimensions of magnetics; improved distribution of losses, with consequent increase of global efficiency and reduction of cost associated to the need of semiconductors with lower current ratings. Three distinct topologies can be derived from the 3SSC: one DC-DC converter with reversible current characteristic able to operate in the first and second quadrants; one DC-DC converter with reversible voltage characteristic able to operate in the first and third quadrants and one DC-DC converter with reversible current and voltage characteristics able to operate in four quadrants. Only the topology with bidirectional current characteristic is analysed in detail in terms of the operating stages in both nonoverlapping and overlapping modes, while the design procedure of the power stage elements is obtained. In order to validate the theoretical assumptions, an experimental prototype is also implemented, so that relevant issues can be properly discussed.
Design of an on-chip hybrid DC/DC converter
Cosp Vilella, Jordi; Martínez García, Herminio
2015-01-01
This paper presents the design of a hybrid on-chip VLSI DC/DC converter for low to medium integrated circuit power consumption that combines a switching and a linear regulator in parallel. The main goal is to take the best of both approaches, obtaining good power efficiency as in switching DC/DC converters, with small voltage output ripple as in linear converters. While the switching regulator is used to drive most of the load current, the linear regulator supplies the required current to fil...
Novel DC/DC Converters For High-Power Distributed Power Systems
Francisco Venustiano, Canales Abarca
2003-01-01
One of the requirements for the next generation of power supplies for distributed power systems (DPSs) is to achieve high power density with high efficiency. In the traditional front-end converter based on the two-stage approach for high-power three-phase DPSs, the DC-link voltage coming from the power factor correction (PFC) stage penalizes the second-stage DC/DC converter. This DC/DC converter not only has to meet the characteristics demanded by the load, but also must process energy w...
A low-delay digital PWM control circuit for DC-DC converters
Ishizuka, Yoichi; Ueno, Masao; Nishikawa, Ichiro; Ichinose, Akira; Matsuo, Hirofumi
2007-01-01
This paper is descried about a proposed scheme of a low-cost digital pulse width modulation (DPWM) control circuit for non-isolated DC-DC converter without A/D converter. Also,real-time PID control technique for DPWM is described. Some experimental results are revealed the proposed circuit and scheme. The purpose of this research is striking a balance between minimizing cost increase by digitalizing of the control circuit of DC-DC converter and speeding up the control circuit.
A new digital control DC-DC converter with peak current -injected control
Kurokawa, Fujio; Sukita, Shohei; Shibata, Yuichiro; Yokoyama, Tomoki; Sasaki, Masahiro; Mimura, Yasuhiro
2008-01-01
This paper presents a new digital control circuit which is able to detect the peak switch current of the high frequency switching dc-dc converter. In this proposed digital control circuit, the peak current-injected control is realized using the combination of the simple dual pulse width modulation analog-to-digital signal converter and the programmed delay circuit. In 100kHz digitally controlled dc-dc converter, it is seen in simulation that the proposed method has no overshoot of the output ...
Multi-output DC-DC converters based on diode-clamped converters configuration
DEFF Research Database (Denmark)
Nami, A.; Zare, F.; Ghosh, A.;
2010-01-01
This study presents a new DC DC multi-output boost (MOB) converter which can share its total output between different series of output voltages for low- and high-power applications. This configuration can be utilised instead of several single output power supplies. This is a compatible topology for...... a diode-clamed inverter in the grid connection systems, where boosting low rectified output-voltage and series DC link capacitors is required. To verify the proposed topology, steady-state and dynamic analyses of a MOB converter are examined. A simple control strategy has been proposed to...
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)
Modelling and Simulation of Digital Compensation Technique for dc-dc Converter by Pole Placement
Shenbagalakshmi, R.; Sree Renga Raja, T.
2015-09-01
A thorough and effective analysis of the dc-dc converters is carried out in order to achieve the system stability and to improve the dynamic performance. A small signal modelling based on state space averaging technique for dc-dc converters is carried out. A digital state feedback gain matrix is derived by pole placement technique in order to achieve the stability of a completely controllable system. A prediction observer for the dc-dc converters is designed and a dynamic compensation (observer plus control law) is provided using separation principle. The output is very much improved with zero output voltage ripples, zero peak overshoot, and much lesser settling time in the range of ms and with higher overall efficiency (>90 %).
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…
Y-Source Boost DC/DC Converter for Distributed Generation
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede;
2015-01-01
This paper introduces a versatile Y-source boost dc/dc converter intended for distributed power generation, where high gain is often demanded. The proposed converter uses a Y-source impedance network realized with a tightly coupled three-winding inductor for high voltage boosting that is presently...
Magnetically coupled high-gain Y-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Loh, Poh Chiang; Blaabjerg, Frede;
2014-01-01
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...
Trans-inverse (Tx−1) high step-up DC-DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang
2015-01-01
In this paper, a new magnetically coupled single-switch non-isolated dc-dc converter with a high voltage gain is proposed. The new topology utilizes a transformer to boost the output voltage. However, unlike other converter topologies with transformer or coupled magnetics, the voltage gain in the...
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)
Single Event Burnout in DC-DC Converters for the LHC Experiments
Energy Technology Data Exchange (ETDEWEB)
Claudio H. Rivetta et al.
2001-09-24
High voltage transistors in DC-DC converters are prone to catastrophic Single Event Burnout in the LHC radiation environment. This paper presents a systematic methodology to analyze single event effects sensitivity in converters and proposes solutions based on de-rating input voltage and output current or voltage.
Soft switching DC/DC converter using controlled output rectifier with auxiliary circuit
Dudrik, Jaroslav; BODOR Marcel; TRIP Daniel Nistor
2010-01-01
Auxiliary circuit for DC/DC converter withcontrolled output rectifier is presented in this paper.Soft switching for power switches of the inverter isachieved by using controlled output rectifier and softswitching of the controlled rectifier by using losslessauxiliary circuit. The principle of converter operationis explained and analyzed and experimental results onthe laboratory model are presented.
Solar Photovoltaic Powered Sailing Boat Using Buck Converter
Soumya Das; Pradip Kumar Sadhu; Nitai Pal; Gourav Majumdar; Saswata Mukherjee
2015-01-01
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 in...
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...
International Nuclear Information System (INIS)
This paper investigates the interest focused on employing parallel connected dc-dc converter with high tracking effectiveness under wide variation in environmental conditions (Insolation) and wide load variation. dc-dc converter is an essential part of the stand alone PV system. Paper also presents an approach on how duty cycle for maximum power position (MPP) is adjusted by taking care of varying load conditions and without iterative steps. Synchronized PWM pulses are employed for the converter. High tracking efficiency is achieved with continuous input and inductor current. In this approach, the converter can he utilized in buck as well in boost mode. The PV system simulation was verified and experimental results were in agreement to the presented scheme. (authors)
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.
Design of a High Efficiency Boost DC-DC Converter
Institute of Scientific and Technical Information of China (English)
GAO Jing; YAO Suying; XU Jiangtao; SHI Zaifeng
2009-01-01
An accurate circuit of PWM/PFM mode converting and a circuit of auto-adaptively adjusting dimension of power transistor are described. The duty cycle of the signal when the control mode converts can be gained accu-rately by using ratios of currents and capacitances, and an optimal dimension of power transistor is derived with different loads. The converter is designed by 0.35 μm standard CMOS technology. Simulation results indicate that the converter starts work at 0.8 V input voltage. Combined with synchronized rectification, the transfer efficiency is higher than 90% with full load range, and achieves 97.5% at rating output.
ZVZCS PWM DC-DC Converter with Energy Recovery Clamp
Directory of Open Access Journals (Sweden)
Vladimir Ruscin
2008-01-01
Full Text Available This paper presents research motivated by industrial demand for special traction drive topology devoted tominimization of traction transformer weight against topology with classical 50Hz traction transformer. The special tractiondrive topology for AC power systems consists of input high voltage trolley converter (single phase matrix converter –middle frequency transformer – output converter - traction motor has been described. The main attention has been given tothe control algorithm of the traction topology (inserting of NULL vector of matrix converter and Two-value control ofsecondary active rectifier.
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 ...... dc-grid system is presented. Finally, a small-scale IFBTL dc/dc converter prototype was built and tested in the laboratory, and the results verify the theoretical analysis.......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...
A Bidirectional Multi-Port DC-DC Converter Integrating Voltage Equalizer
DEFF Research Database (Denmark)
Chen, Jianfei; Hou, Shiying; Deng, Fujin;
2015-01-01
A novel bidirectional multi-port dc-dc converter integrating voltage equalizer based on switched-capacitor voltage accumulator (SCVA) is proposed. It has two operating modes of charging and discharging for battery modules. All battery modules are connected in series indirectly and can be equalized...
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...
Analysis and design of PPFHB bidirectional DC-DC converter with coupled inductors
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
In this paper, a novel push-pull-forward half-bridge (PPFHB) bi-directional DC-DC converter with coupled inductors is proposed. All switches can operate under zero-voltage-switching (ZVS). The operation principle with phase-shift modulation scheme, characteristics of coupled inductors, the steady...
Integrated S-band transmitter with on-chip DC-DC converter and control loop
Brouzes, H.; Geurts, S.; Besselink, M.; Telli, A.; Hek, A.P. de; Bent, G. van der; Vliet, F.E. van
2012-01-01
A highly integrated high-power transmitter has been designed in a high breakdown GaAs MMIC technology. The transmitter includes, on top of an S-Band 10 W class-F HPA, a DC/DC converter and its associated gate driver, the full voltage regulation control loop, which provides a significant step for pha
A high voltage ratio and low ripple interleaved DC-DC converter for fuel cell applications.
Chang, Long-Yi; Chao, Kuei-Hsiang; Chang, Tsang-Chih
2012-01-01
This paper proposes a high voltage ratio and low ripple interleaved boost DC-DC converter, which can be used to reduce the output voltage ripple. This converter transfers the low DC voltage of fuel cell to high DC voltage in DC link. The structure of the converter is parallel with two voltage-doubler boost converters by interleaving their output voltages to reduce the voltage ripple ratio. Besides, it can lower the current stress for the switches and inductors in the system. First, the PSIM software was used to establish a proton exchange membrane fuel cell and a converter circuit model. The simulated and measured results of the fuel cell output characteristic curve are made to verify the correctness of the established simulation model. In addition, some experimental results are made to validate the effectiveness in improving output voltage ripple of the proposed high voltage ratio interleaved boost DC-DC converters. PMID:23365536
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 Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase-shift modulation scheme, all the switches can realize zero-voltageswitching (ZVS) turn-on and bidirectional power flow can be controlled with phase-shift angle. The operating principles of the converter are descr...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2013-01-01
capacitive sub-actuators. It needs to be driven by three high voltage (~2.5 kV) DC-DC converters, to achieve the linear incremental motion. The topology used for this application is a bi-directional flyback DC-DC converter. The control of the incremental actuator involves, implementation of digital...
Soft switching DC/DC converter using auxiliary circuits
Jaroslav Dudrik; Vladimír Ruščin
2008-01-01
A novel auxiliary circuit for full-bridge PWMDC/DC converter with controlled secondary side rectifieris presented in this paper. Zero-current turn-on for allpower switches of the inverter is achieved for full loadrange from no-load to short circuit by using controlledrectifier and auxiliary circuit on the secondary side.Modified phase shift PWM control strategy is used for theconverter. The principle of operation is explained andanalyzed and the simulation results are presented.
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)
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...
High Voltage Coil Current Sensor for DC-DC Converters Employing DDCC
Directory of Open Access Journals (Sweden)
M. Drinovsky
2015-12-01
Full Text Available Current sensor is an integral part of every switching converter. It is used for over-current protection, regulation and in case of multiphase converters for balancing. A new high voltage current sensor for coil-based current sensing in DC-DC converters is presented. The sensor employs DDCC with high voltage input stage and gain trimming. The circuit has been simulated and implemented in 0.35 um BCD technology as part of a multiphase DC-DC converter where its function has been verified. The circuit is able to sustain common mode voltage on the input up to 40 V, it occupies 0.387*0.345 mm2 and consumes 3.2 mW typically.
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.
Parallel-Connected Solar Photovoltaic with Ultra Low Voltage DC/DC Converter
Zhiwen Yu; Da Xie; Junqi Feng
2013-01-01
In series-connected wiring scheme, the residual energy generated by partially shaded cells cannot be collected or, worse, impedes collection of power from the remaining fully illuminated cells. In this paper, a parallel-connected topology is introduced to PV panel. Each cell, connected to the dc bus paralleled with a special converter, is treated as a voltage source. The dc-dc converter is introduced to realize the method, which could work under an ultra-low-voltage (ULV). Efficiency comparis...
Average current control of DC-DC Cuk Converters as Power Factor Corrector
Ashima Kulshreshtha; Anmol R. Saxena
2015-01-01
The era of electronic devices in all loads due to the manufacturing technologies replaced many conventional electrical or mechanical loads including lighting loads where Light Emitting Diodes (LEDs) is becoming an emerging technique with many advantages. High frequency switching dc-dc converter is a new technology to control the load and the supply side simultaneously. Due to additional harmonics generated by these switching converters power factor correction has become a necessit...
Impact of dielectric deterioration on the conducted EMI emissions in the DC-DC boost converter
Musznicki, Piotr; Schanen, Jean-Luc; Granjon, Pierre; Јuszcz, Jarosław
2011-01-01
International audience The magnitude of emitted noise generated by DC-DC converters depends on their electrical behavior and parameters. Some of these can change during the converter life time, especially due to some deterioration process. In this paper the impact of the dielectric materials aging is presented using both circuit simulation and a digital signal processing method based on Wiener filtering. The change of the total EMI spectrum as a function of the dielectric property has been...
Current-Steering Switching Policy for a SIDO Linear-Assisted Hysteretic DC/DC Converter
Martínez García, Herminio; Silva-Martínez, José; Alarcón Cot, Eduardo José; Poveda López, Alberto
2010-01-01
This paper proposes the use of linear-assisted switching power converters in the context of single-inductor dual-output (SIDO) applications. By combining a DC/DC ripplecontrolled switching power converter with the respective voltage linear regulators at each output, improved performance in terms of load and line regulations is obtained. To achieve that aim, a current-steering switching policy is proposed, together with a resource-aware circuit implementation. The ripple-based hysteretic...
Inverse optimal control as an alternative to regulate a Boost DC-DC power converter
Directory of Open Access Journals (Sweden)
Carlos Jesús Vega Pérez
2015-11-01
Full Text Available This article presents the application of the fundamental theory of the inverse optimal control problem for regulation of the output voltage in a Boost DC-DC power converter. The inverse optimal control problem states a priori an optimal control law and a posteriori it proposes the functional cost to be minimized, avoiding the explicit solution of the Hamilton-Jacobi-Bellman equation and, therefore, making easier the solution of the optimal control problem. Some analytical developments are shown here to obtain mathematical expressions needed to perform the inverse optimal control approach on regulation of the output voltage in a Boost power converter circuit under the influence of external disturbances. Numerical routines performed in MATLAB® have shown promising results of the proposed technique by achieving annihilation of the perturbation effect in the system´s model. Future work is focused on experimental verification of this approach on a real prototype of the DC-DC converter.
Voltage Tracking of a DC-DC Flyback Converter Using Neural Network Control
Directory of Open Access Journals (Sweden)
Wahyu Mulyo Utomo
2012-01-01
Full Text Available This paper proposes a neural network control scheme of a DC-DC Flyback converter that will step up a 12V DC and applied it on brushless DC motor with 12 and 24V dc. In this technique, a back propagation learning algorithm is derived. The controller is designed to track the output voltage of the DC-DC converter and to improve performance of the Flyback converter during transient operations. Furthermore, to investigate the effectiveness of the proposed controller, some operations such as starting-up and reference voltage variations are verified. The numerical simulation results show that the proposed controller has a better performance compare to the conventional PI-Controller method.
A Dual-Input DC-DC Converter Using Clean Energy Power Supplies
Eguchi, Kei
2010-01-01
In this chapter, a serial SC DC-DC converter using clean energy power supplies has been proposed. The validity of the circuit design was conï¬rmed by theoretical analyses, SPICE simulations, and experiments. The proposed converter can realize not only long battery runtime but also small hardware-cost and wide input-range. Concretely, in comparison with the conventional parallel converter using 1.5Ã— step-up SC converters, the proposed converter can achieve 20%
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...
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...... bifurcations as a complex behaviour in power electronic system evidence are also described. In order to verify theoretical study the experimental DC-DC buck converter was build. The results obtained from three sources were presented and compared. A very good agreement between theory and experiment was observed....
A High Voltage Ratio and Low Ripple Interleaved DC-DC Converter for Fuel Cell Applications
Long-Yi Chang; Kuei-Hsiang Chao; Tsang-Chih Chang
2012-01-01
This paper proposes a high voltage ratio and low ripple interleaved boost DC-DC converter, which can be used to reduce the output voltage ripple. This converter transfers the low DC voltage of fuel cell to high DC voltage in DC link. The structure of the converter is parallel with two voltage-doubler boost converters by interleaving their output voltages to reduce the voltage ripple ratio. Besides, it can lower the current stress for the switches and inductors in the system. First, the PSIM s...
On the Robust Control of DC-DC Converters: Application to a Hybrid Power Generation System
Hernandez-Torres, David; Sename, Olivier; Riu, Delphine; Druart, Florence
2010-01-01
In this paper a complete robust control synthesis is performed for a hybrid power generation structure composed by a Fuel Cell and a Supercapacitor. The control strategies are applied to the DC-DC boost power converters associated to each power source. Multivariable PI control with H∞ performance, H∞ full and reduced order controllers are designed and compared. The multivariable PI controller is designed through an optimization procedure based on solving some Linear Matrix Inequalities. A μ-a...
An adaptive digital controller for satellite medium power DC/DC converter
Skup, Konrad R.; Grudziński, Paweł; Orleański, Orleański
2011-01-01
In this paper the work concerning an adaptive digital controller for satellite medium power DC/DC converters is presented. The adaptive techniques and methods developed in Space Research Centre allows an implemented in VHDL controller to modify its parameters according to detected changes in operating conditions. Inductor entering from discontinuous to continuous current mode and vice versa or moving sampling instants due to changes in duty time are good examples of varying operation...
A high voltage gain quasi Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang;
2014-01-01
A compact quasi-Z-source DC/DC converter is presented with high voltage gain, isolated output, and improved efficiency. The improvements in size and performance were achieved by using a square wave inverter with only two output switches driving an isolating transformer in push-pull mode, followed...... constructed and tested. The efficiency at full load varied from 89.0% to 97.4% as the input voltage changed from 44 V to 82 V....
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 has been designed and simulated and also compared with theoretical predictions.
Directory of Open Access Journals (Sweden)
V.V.Subrahmanya Kumar Bhajana
2012-06-01
Full Text Available A novel active clamp dual half bridge DC/DC converter with bidirectional power flow is proposed in this paper and comparative analysis between active clamp DHB ZVZCS and ZVS-ZCS bidirectional DC-DC converter topologies is also presented. By adding active clamping circuits to both bridges, zero voltage and zero current switching are achieved to improve the performance of the bidirectional DC/DC converter. The principle of operation is analyzed and simulated. With the proposed active clamp ZVZCS concept, the MATLAB simulation results of the applications of the fuel cell and battery have been obtained and compared with those of ZVS-ZCS bidirectional converter. The simulation results of proposed converter is compared with the ZVS-ZCS bidirectional DC-DC converter, efficiency, switching losses are the key parameters compared.
A Protection Circuit for DC-DC Converter with Voltage Doubler
D. Elangovan; A.Gopi; Dr.R.Saravanakumar
2012-01-01
This paper proposes a method to obtain a protected voltage gain by employing a protection circuit for the voltage doubler or multiplier circuit in an isolated tyde DC-DC Converter. The entire set up consists of a phase shift converter with a protected bridge/voltage doubler rectifier on the output side. The operating frequency of the phase shift converter is 20-25kHz (depending on the requirement of the application) which is high enough to improve the efficiency. Ferrite core transformer is u...
A DC-DC Converter with Wide Input Voltage Range for Fuel Cell and Supercapacitor Application
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
voltage doubler circuit in secondary side. Boost type converter can limit the output ripple current of the fuel cells; hybrid full-bridge structure can change operating modes according to the different input voltage; phase-shift with duty cycle control scheme is utilized to control the bidirectional power......This paper proposes a novel phase-shift plus duty cycle controlled hybrid bi-directional DC-DC converter based on fuel cells and supercapacitors. The described converter employs two high frequency transformers to couple the half-bridge and full-bridge circuits together in the primary side and...
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Thomsen, Ole Cornelius;
2011-01-01
, hereby increasing the power density of converters. In this paper, a new planar integrated magnetics (PIM) module for a phase-shift plus duty cycle controlled hybrid bi-directional dc-dc converter is proposed, which assembles one boost inductor and two transformers into an E-I-E core geometry, reducing...... the number of parts, the total volume of converter, as well as the total core loss of the magnetic components. AC losses in the windings and leakage inductance of the transformers are kept low by interleaving the primary and secondary turns of the transformers. To verify the validity of the design...
Multiple output zero-current switching switched-capacitor bidirectional dc-dc converter
Lee, Yuang-Shung; Ko, Yi-Pin; Chi, Chien-An
2010-08-01
The proposed circuit is a multiple output quasi-resonant (QR) zero-current switching (ZCS) switched-capacitor (SC) converter with a bidirectional power flow control conversion scheme. The principles of the proposed multiple output QR ZCS SC bidirectional dc-dc converter are described using a detailed circuit model for analysis. Simulation and experimental results are carried out to verify the validity and the soft switching performance of the proposed converter. The maximum efficiency achievable is about 94 and 92% for the forward and reverse power flow control schemes, respectively. The output voltage can be regulated by changing the switching frequency for the designed compensated closed-loop controller.
A Novel PPFHB Bidirectional DC-DC Converter for Supercapacitor Application
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
This paper presents a novel bidirectional DC-DC converter for the supercapacitor application. In the proposed converter, push-pull forward with half bridge (PPFHB) voltage doubler structure is used to reduce the number of the power switches and get higher voltage gain. Based on phase......-shift modulation scheme, all the switches can realize zero-voltageswitching (ZVS) turn-on and bidirectional power flow can be controlled with phase-shift angle. The operating principles of the converter are described in detail, ZVS conditions are discussed, parameters are designed, and the experimental results...
S.Augustilindiya; Palani, S.; K.Vijayarekha; M.BreethiYeltsina
2013-01-01
Tuning PID controller parameters using Evolutionary algorithm for an asynchronous Buck converter is presented in this paper. PID controller is one of the solutions for controlling a Buck converter during transient conditions. There are straight forward ways for calculating the parameters for the PID controller in the literature and evolutionary algorithm based approach with a proper fitnessfunction gives superior performance when compared to other methods. Ziegler Nicholas method, Hurwitz pol...
Transformerless DC-DC Converter Using Cockcroft-Walton Voltage Multiplier to Obtain High DC Voltage
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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.
Design and Implementation of Digital Current Mode Controller for DC-DC Converters
DEFF Research Database (Denmark)
Taeed, Fazel
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...
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
This paper introduces a new single-switch nonisolated dc-dc converter with very high voltage transfer ratio and reduced semiconductor voltage stress. The converter utilizes an integrated autotransformer and a coupled inductor on the same core to achieve a high step-up voltage gain without extreme...... to use a low voltage and low RDS-on MOSFET, which reduces the cost, and also the conduction and turn on losses of the switch. The principle of operation and theoretical analysis supported by key simulation and experimental waveforms are presented in details....
Multi-Level DC-DC Converter for High Gain Applications
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Girish Ganesan R
2013-12-01
Full Text Available The output voltage from most renewable energy sources like photovoltaic arrays and fuel cells will be at low level. This must be stepped up considerably for practical utilization or grid connection. The presented multilevel boost converter DC-DC converter topology consists of the conventional boost converter and voltage doubler stages to provide high voltage gain. The proposed topology uses only one switch along with one inductor, (2N-1 diodes and (2N-1 capacitors for obtaining an output which is N times the conventional boost converter. In this topology, each device blocks only one voltage level. The main advantages of this topology are continuous input current, large gain without high duty cycle or transformer, modularity and use of devices with low voltage ratings. Experimental results obtained from the 100W prototype demonstrate the voltage gain capability of the converter and validates the converter design.
Y-source impedance-network-based isolated boost DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Town, Graham; Loh, Poh Chiang;
2014-01-01
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...... with a relatively low duty cycle of the switches, and the gain obtainable is presently not matched by any existing impedance network based converter operated at the same duty ratio. The proposed converter has a Y-source impedance network to boost the voltage at the intermediate dc-link side and a push......-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...
Comparison of two different high performance mixed signal controllers for DC/DC converters
DEFF Research Database (Denmark)
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2006-01-01
This paper describes how mixed signal controllers combining a cheap microcontroller with a simple analogue circuit can offer high performance digital control for DC/DC converters. Mixed signal controllers have the same versatility and performance as DSP based controllers. It is important to have an...... engineer experienced in microcontroller programming write the software algorithms to achieve optimal performance. Two mixed signal controller designs based on the same 8-bit microcontroller are compared both theoretically and experimentally. A 16-bit PID compensator with a sampling frequency of 200 k...
Comparison of two different high performance mixed signal controllers for DC/DC converters
DEFF Research Database (Denmark)
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2006-01-01
This paper describes how mixed signal controllers combining a cheap microcontroller with a simple analogue circuit can offer high performance digital control for DC/DC converters. Mixed signal controllers have the same versatility and performance as DSP based controllers. It is important to have an...... engineer experienced in microcontroller programming write the software algorithms to achieve optimal performance. Two mixed signal controller designs based on the same 8-bit microcontroller are compared both theoretically and experimentally. A 16-bit PID compensator with a sampling frequency of 200 k......Hz implemented in the 16 MIPS, 8-bit ATTiny26 microcontroller is demonstrated....
Four Quadrants Integrated Transformers for Dual-input Isolated DC-DC Converters
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Andersen, Michael A. E.;
2012-01-01
A common limitation of power coupling effect in some known multiple-input dc-dc converters has been addressed in many literatures. In order to overcome this limitation, a new concept for decoupling the primary windings in the integrated multiple-winding transformers based on 3-dimensional (3D...... perpendicular primary windings, a name of “four quadrants integrated transformers” (FQIT) is therefore given to the proposed construction. Since the two primary windings are uncoupled, the FQIT allows the two input power stages to transfer the energy into the output load simultaneously or at any...
Fuzzy control of the DC-DC converter used as power interface for a fuel cell
International Nuclear Information System (INIS)
In this paper it is analyzed a feed-forward fuzzy control for PWM control of the DC-DC converter using a fuel cell as energy source. For a dynamic load the fuel cell output voltage vary in large DC range and the high DC voltage stabilization can not be a difficult task. The advantages of the forward loop after the fuel cell output voltage concerning the stability and robustness of fuzzy control are compared with the best results obtained using a well designed proportional-integral control. The Simulink models for the used blocks, simulation results, and some design consideration are presented, too. (authors)
Analysis and design of PPFHB bidirectional DC-DC converter with coupled inductors
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael Andreas E.
2009-01-01
In this paper, a novel push-pull-forward half-bridge (PPFHB) bi-directional DC-DC converter with coupled inductors is proposed. All switches can operate under zero-voltage-switching (ZVS). The operation principle with phase-shift modulation scheme, characteristics of coupled inductors, the steady state relationship and small-signal model are analyzed. The voltage controller based on the small-signal model in z-domain is designed. A 500W prototype controlled by TMS320F2808 DSP is implemented a...
Analysis and Implementation of Dual-ZCS forward DC/DC Converter
Institute of Scientific and Technical Information of China (English)
WANG Jing-mei; LAN Zhong-wei; YU Zhong; WANG Hao-cai
2005-01-01
As the switching frequency in DC/DC converter increases, original 'hard-switch' working mode is not compatible. Another problem is the reliability, which is puzzled in single-ended forward, push-pull or bridge-like structures. In this paper, a new dual-ZCS (zero current switches) forward topology is proposed. The operating principle of soft-switch is analyzed, showing the relationship between voltage and current in time domain. Then how to calculate the key parameters of resonant network is . Finally, a prototype ZCS SMPS is implemented and tested. The results consisted with the analyzing results well, and illustrated the advantages of the proposed structure.
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.
Modeling and Simulation of Sensorless Speed Control of a Buck Converter Controlled Dc Motor
Tagreed M. Ali; Bassim M. H. Jassim
2010-01-01
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.
Non-Inverting Buck-Boost Converter for Fuel Cell Applications
DEFF Research Database (Denmark)
Schaltz, Erik; Rasmussen, Peter Omand; Khaligh, Alireza
2008-01-01
Fuel cell DC/DC converters often have to be able to both step-up and step-down the input voltage, and provide a high efficiency in the whole range of output power. Conventional negative output buck-boost and non-inverting buck-boost converters provide both step-up and step-down characteristics....... In this paper the non-inverting buck-boost with either diodes or synchronous rectifiers is investigated for fuel cell applications. Most of previous research does not consider the parasitic in the evaluation of the converters. In this study, detailed analytical expressions of the efficiencies for the system...
Planar integrated magnetics design in wide input range DC-DC converter for fuel cell application
DEFF Research Database (Denmark)
Ouyang, Ziwei; Zhang, Zhe; Thomsen, Ole Cornelius;
2010-01-01
In the most power electronics converters, the overall volume is mainly determined by the number of parts and the size of passive components. Integrated magnetics and planar magnetics techniques therefore have been an excellent option in order to reduce the count and the size of magnetic components......, hereby increasing the power density of converters. A new planar integrated magnetics (PIM) technique for a phase-shift plus duty cycle controlled hybrid bi-directional DC/DC converter is presented and investigated in this paper. The main magnetic components including one boost inductor and two...... independent transformers are integrated into an E-I-E core geometry. Utilizing the flux cancellation as the principle of uncoupling, the transformers and the boost inductor are integrated, to reduce the total ferrite volume and core loss. The transformers and inductor are wound in the outer legs and the...
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
A Compact, Soft-Switching DC-DC Converter for Electric Propulsion
Button, Robert; Redilla, Jack; Ayyanar, Raja
2003-01-01
A hybrid, soft-switching, DC-DC converter has been developed with superior soft switching characteristics, high efficiency, and low electro-magnetic interference. This hybrid topology is comprised of an uncontrolled bridge operating at full pulse-width, and a controlled section operating as a conventional phase modulated converter. The unique topology is able to maintain zero voltage switching down to no load operating conditions. A breadboard prototype was developed and tested to demonstrate the benefits of the topology. Improvements were then made to reduce the size of passive components and increase efficiency in preparation for packaging. A packaged prototype was then designed and built, and several innovative packaging techniques are presented. Performance test data is presented that reveals deficiencies in the design of the power transformer. A simple redesign of the transformer windings eliminated the deficiency. Future plans to improve the converter and packaging design are presented along with several conclusions.
A High Voltage-lift Efficient Isolated Full Bridge DC-DC Converter
Directory of Open Access Journals (Sweden)
A. Gopi
2014-05-01
Full Text Available The aim of this study is to propose a high voltage lift isolated full bridge dc-dc converter. The proposed converter consists of an isolation transformer a low turn ratio to obtain high step up voltage gain. The secondary of the transformer connected with two boosting capacitors which connects parallel when power switches switch on period and discharged in series during the switch off period. In addition full bridge converter on primary side consists of clamping diode and capacitor, leakage energy is recycled there by improving conversion efficiency. The proposed circuits simulated using PSIM software form input voltage of 48V, an output of 410 V obtained. These results and operations experimented and validated by implementing in hardware model at 20/40 Vdc, 20 Watts.
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...
Institute of Scientific and Technical Information of China (English)
陈楠; 魏廷存; 陈笑
2016-01-01
针对高频DC-DC开关变换器，提出了数字控制DC-DC开关变换器的邻周期采样（ adjacent cycle sampling ，ACS）控制方法，缓解硬件处理速度与系统瞬态性能之间的矛盾。依据纹波控制方法，ACS控制算法利用硬件空闲阶段采样数据，增大环路预留时间，消除占空比的影响。采用ACS控制算法，推导出适用于后缘调制降压型DC-DC开关变换器的数字V2控制律和电流控制律，并且研究了次谐振荡现象及其数字斜坡补偿消除方法。仿真结果表明，在相同的硬件条件，对于负载的瞬间扰动，数字V2控制较数字电流控制具有更快的瞬态响应速度；与现有技术相比，ACS控制方法可有效提高系统的瞬态响应性能。%Adjacent cycle sampling ( ACS) control method applied to high switching frequency converters for the digitally controlled DC-DC switching converters was proposed .ACS control method can effectively relieve the contradiction between hardware processing speed and transient response performance .Accord-ing to ripple control method,ACS control method sampling the data in idle time increased the available time for duty ratio updating ,and furthermore it was irrelevant to duty ratio .For the buck DC-DC switching converters with trailing-edge modulation ,the control laws of both the digital V 2 control and the digital cur-rent control were derived based on ACS control method .Moreover ,the harmonic oscillation phenomenon of above control laws was analyzed and eliminated using digital slope compensation method .The simula-tion results show that ,for the load instantaneous disturbance ,the digital V 2 control has faster transient re-sponse speed than the digital current control under the same hardware resources .As compared with the conventional technologies ,the ACS control method can effectively improve the transient response perform-ance of DC-DC converters .
Two-Phase Interleaved Buck Converter with a new Digital Self-Oscillating Modulkator
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2007-01-01
This paper presents a new Digital Self-Oscillating Modulator (DiSOM) for DC/DC converters. The DiSOM modulator alllows the digital control algorithm to sample the output voltage at a sampling frequency higher than the converter switching frequency. This enables higher control loop bandwidth than for traditional digital PWM modulators given a certain switching frequency. A synchronised version of the DiSOM modulator is derived for interleaved converters. A prototype interleaved Buck converter ...
A Stable Control Strategy for Input-Series Output-Series Connected Boost half Bridge DC-DC Converter
Directory of Open Access Journals (Sweden)
Shahnawaz Farhan Khahro
2013-07-01
Full Text Available Boost half bridge DC-DC converters in the combination of an input-series and output-series (ISOS connected configuration with a stable control strategy has been investigated in this paper. A stable control strategy comprises of two loops that are current loop and voltage loop. The reference to the current loop has been chosen from the input side of the DC-DC converter. The reference to the voltage loop has been selected from the output side of the DC-DC converter. Such a reference makes the circuit configuration simple, easy and eventually results in reduced cost. The control strategy for input-series output-series (ISOS configuration of DC-DC converters is proposed to achieve equal input voltage sharing (IVS as well output voltage sharing (OVS. Furthermore, in this paper, the performance of the stable control strategy for input-series output-series (ISOS boost half bridge DC-DC converter has been observed not only for the fixed but also for the varying and continuously varying load. The proposed Stable control scheme has been developed by modeling it on MATLAB using Simulink and Simpower toolboxes. The operation of the proposed stable control strategy has been found to be satisfactory.
ASIC and FPGA based DPWM architectures for single-phase and single-output DC-DC converter: a review
Chander, Subhash; Agarwal, Pramod; Gupta, Indra
2013-12-01
Pulse width modulation (PWM) has been widely used in power converter control. This paper presents a review of architectures of the Digital Pulse Width Modulators (DPWM) targeting digital control of switching DC-DC converters. An attempt is made to review the reported architectures with emphasis on the ASIC and FPGA implementations in single phase and single-output DC-DC converters. Recent architectures using FPGA's advanced resources for achieving the resolution higher than classical methods have also been discussed. The merits and demerits of different architectures, and their relative comparative performance, are also presented. The Authors intention is to uncover the groundwork and the related references through this review for the benefit of readers and researchers targeting different DPWM architectures for the DC-DC converters.
Directory of Open Access Journals (Sweden)
Zheng Wang
2016-01-01
Full Text Available Three-port isolated (TPI bidirectional DC/DC converters have three energy ports and offer advantages of large voltage gain, galvanic isolation ability and high power density. For this reason this kind of converters are suitable to connect different energy sources and loads in electric and hybrid vehicles. The purpose of this paper is to propose chaotic modulation and the related control scheme for TPI bidirectional DC/DC converters, in such a way that the switching harmonic peaks can be suppressed in spectrum and the conducted electromagnetic interference (EMI is reduced. Two chaotic modulation strategies, namely the continuously chaotic modulation and the discretely chaotic modulation are presented. These two chaotic modulation strategies are applied for TPI bidirectional DC/DC converters with shifted-phase angle based control and phase-shifted PWM control. Both simulation and experiments are given to verify the validity of the proposed chaotic modulation-based control schemes.
High Step-Up DC-DC Converter for Distributed Generation System
Directory of Open Access Journals (Sweden)
V.K. Jayakrishnan
2013-08-01
Full Text Available This study proposes a method which consists of High step up DC-DC converter with a coupled inductor for distributed generation system. Theoretically the conventional boost converter provides high step up voltage gain but in practical it is limited by reverse recovery problem of diode, effective series impedance of inductors and capacitors and switching losses. High charged current and conduction losses occur in the switch when voltage lift and switched capacitor techniques are used. In the proposed strategy a coupled-inductor and two capacitors is utilized to achieve high step-up voltage gain. High power loss and voltage spike on the switch is avoided using passive clamp circuit that recycles the leakage inductor energy. The operating principle and steady-state analysis are discussed. The Proposed topology was simulated using PSPICE SOFTWARE and the following results were obtained. For an input voltage of 24V, an output of 333V was obtained.
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.
DC-DC converters for the upgrades of the CMS tracker
International Nuclear Information System (INIS)
Within the present decade, it is foreseen to gradually increase the instantaneous luminosity of the LHC to 1-2.1034 cm-2s-1. Around 2020, it is intended to increase the luminosity further, to about 5.1034 cm-2s-1. To ensure and improve its physics performance, CMS is going to exchange its pixel detector around 2016. Four years later the complete tracker is going to be replaced by a new development. The use of DC-DC converters is foreseen for both of these upgrades. Radiation tolerant converters developed by working groups at CERN and Aachen match the requirements of the new pixel detector already. However, further work is required to integrate the converters on system level and to ensure their save and reliable operation. The status of this work is presented. Building a new tracking detector equipped with converters, raises several additional challenges. In particular the noise performance of the converters and their efficiency at large conversion ratios still has to be improved. The coil, used by the converters to buffer energy, has a significant impact on both of these issues. Effort has been put into the optimization of converter coils, as well as into the exploration and minimization of noise radiated by the coils. The talk gives a summary of the results of this work.
A Family of Step-up DC/DC Converters with Fast Dynamic Response for Low Power Applications
DEFF Research Database (Denmark)
N. Soltani, Mohsen; Mostaan, Ali; Siwakoti, Yam Prasad;
2016-01-01
This paper presents a family of novel step-up DC/DC converters which do not have a right half plane zero in their transfer function resulting in faster dynamic behavior of the converters under the load variation. In addition, the voltage stress on all the active switches and diodes is as low as t...
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.
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.
Ultra-high Efficiency DC-DC Converter using GaN Devices
DEFF Research Database (Denmark)
Ramachandran, Rakesh
2016-01-01
The demands for high efficiency dc-dc power converters are increasing day by day in various applications such as telecommunication, data-centers, electric vehicles and various renewable energy systems. Silicon (Si) has been used as the semiconductor material in majority of the power devices for...... many decades. However, the rate of improvement slowed as the silicon power materials asymptotically approached its theoretical bounds. Compared to Si, wideband gap materials such as Silicon Carbide (SiC) and Gallium Nitride (GaN) are promising semiconductors for power devices due to their superior...... material properties such as high temperature operation, high breakdown voltage and high frequency operation. Among wide band-gap devices, GaN has an enhanced mobility of electrons, compared to SiC, which helps in achieving smaller size for a given on-resistance and breakdown voltage. These superior...
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 μm 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.
Directory of Open Access Journals (Sweden)
S.Augustilindiya
2013-08-01
Full Text Available Tuning PID controller parameters using Evolutionary algorithm for an asynchronous Buck converter is presented in this paper. PID controller is one of the solutions for controlling a Buck converter during transient conditions. There are straight forward ways for calculating the parameters for the PID controller in the literature and evolutionary algorithm based approach with a proper fitnessfunction gives superior performance when compared to other methods. Ziegler Nicholas method, Hurwitz polynomial method and Genetic Algorithm based method are compared. It is found that Genetic Algorithm based method yields better result. The hardware implementation of Genetic Algorithm assisted PID controller with low cost is desired and such an implementation is taken in this paper. A low cost microcontroller with built-in PWM modules is implemented and the performance is compared with simulations.
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
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...
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
A Protection Circuit for DC-DC Converter with Voltage Doubler
Directory of Open Access Journals (Sweden)
D.Elangovan
2012-12-01
Full Text Available This paper proposes a method to obtain a protected voltage gain by employing a protection circuit for the voltage doubler or multiplier circuit in an isolated tyde DC-DC Converter. The entire set up consists of a phase shift converter with a protected bridge/voltage doubler rectifier on the output side. The operating frequency of the phase shift converter is 20-25kHz (depending on the requirement of the application which is high enough to improve the efficiency. Ferrite core transformer is used in place of ordinary air core transformer, which is small in size with number of turns of the transformer is reduced and the overall power density is increased. The doubler circuit consists of electrolytic capacitors, which are rated at 400V in order to comply with IEC65 requirements. This paper proposes an “electrolytic capacitor protection circuit”, which enables the voltage rating of the electrolytics to be reduced to 250V. This circuit results in cost savings of more than 50% in the price of the electrolytic filter capacitors. The circuits were simulated using PSPICE SOFTWARE and the following results were obtained. For an input voltage of 200V, an output of 200V and400V were obtained in bridge mode and doubler mode respectively.
SWITCH MODE PULSE WIDTH MODULATED DC-DC CONVERTER WITH MULTIPLE POWER TRANSFORMERS
DEFF Research Database (Denmark)
2009-01-01
A switch mode pulse width modulated DC-DC power converter comprises at least one first electronic circuit on a input side (1) and a second electronic circuit on a output side (2). The input side (1) and the output side (2) are coupled via at least two power transformers (T1, T2). Each power...... transformer (T1, T2) comprises a first winding (T1a, T2a) arranged in a input side converter stage (3, 4) on the input side (1) and a second winding (T1 b, T2b) arranged in a output side converter stage (5) on the output side (2), and each of the windings (T1a, T1 b, T2a, T2b) has a first end and a second end...... switches being adapted to switch the current through the first winding (T1 a, T2a) between a first ON-state, a first OFF-state, a second ON-state with a polarity opposite to the first ON-state, and a second OFF-state, and/or being adapted to provide rectified current to the terminals (AO, A1) wherein the...
A Monolithically Integrated 12V/5V Switch-Capacitor DC-DC Converter
Institute of Scientific and Technical Information of China (English)
耿莉; 陈治明; 刘先锋
2000-01-01
A monolithically integrated 12V/SV switch capacitor DC-DC converter with structure-simplified main circuit and control circuit is presented. Its topological circuit and basic operating principle are discussed in detail. It is shown that elevated operating frequency, increased capacitance and reduced turn-on voltage of the diodes can make the converter's output characteristics improved. Reducing resistance of the equivalent resistors and other parasitic parameters can make the operation frequency higher. As a feasible efficient method to fabricate monolithically integrated converter with high frequency and high output power, several basic circuits are parallelly combined where the serial-parallel capacitance is optimized for the maximum output power. The device selection and its fabrication method are presented. A feasible integration process and its corresponding layout are designed. All active devices including switching transistors and diodes are integrated together with all passive cells including capacitors and resistor on a single chip based on BiMOS process,as has been verified to be correct and practical by simulation and chip test.
Directory of Open Access Journals (Sweden)
R. Silva-Ortigoza
2014-01-01
Full Text Available Sliding mode control is a discontinuous control technique that is, by its nature, appropriate for controlling variable structure systems, such as the switch regulated systems employed in power electronics. However, when designing control laws based on the average models of these systems a modulator is necessary for their experimental implementation. Among the most widely used modulators in power electronics are the pulse width modulation (PWM and, more recently, the sigma-delta-modulator (Σ-Δ-modulator. Based on the importance of achieving an appropriate implementation of average control laws and the relevance of the trajectory tracking task in DC/DC power converters, for the first time, this research presents the assessment of the experimental results obtained when one of these controllers is implemented through either a PWM or a Σ-Δ-modulator to perform such a task. A comparative assessment based on the integral square error (ISE index shows that, at frequencies with similar efficiency, the Σ-Δ-modulator provides a better tracking performance for the DC/DC Buck converter. In this paper, an average control based on differential flatness was used to perform the experiments. It is worth mentioning that a different trajectory tracking controller could have been selected for this research.
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...
Dual-Input Isolated Full-Bridge Boost DC-DC Converter Based on the Distributed Transformers
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;
2012-01-01
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...
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…
Progress on DC-DC Converters for a Silicon Tracker for the sLHC Upgrade
Dhawan, S; Chen, H; Khanna, R; Kierstead, J; Lanni, F; Lynn, D; Musso, C; Rescia, S; Smith, H; Tipton, P; M. Weber, M
2009-01-01
There is a need for DC-DC converters which can operate in the extremely harsh environment of the sLHC Si Tracker. The environment requires radiation qualification to a total ionizing radiation dose of 50 Mrad and a displacement damage fluence of 5 x 1014 /cm2 of 1 MeV equivalent neutrons. In addition a static magnetic field of 2 Tesla or greater prevents the use of any magnetic components or materials. In February 2007 an Enpirion EN5360 was qualified for the sLHC radiation dosage but the converter has an input voltage limited to a maximum of 5.5V. From a systems point of view this input voltage was not sufficient for the application. Commercial LDMOS FETs have developed using a 0.25 μm process which provided a 12 volt input and were still radiation hard. These results are reported here and in previous papers. Plug in power cards with ×10 voltage ratio are being developed for testing the hybrids with ABCN chips. These plug-in cards have air coils but use commercial chips that are not designed to be radiatio...
High-Temperature SOI/SiC-Based DC-DC Converter Suite
Directory of Open Access Journals (Sweden)
Brice McPherson
2008-08-01
Full Text Available A complete design strategy (mechanical and electrical for a 25Ã¢Â€Â‰W 28Ã¢Â€Â‰V/5Ã¢Â€Â‰V dc-dc converter utilizing SiC and SOI electronics is presented. The converter includes a high-temperature SOI-based PWM controller featuring 150Ã¢Â€Â‰kHz operation, a PID feedback loop, maximum duty cycle limit, complementary or symmetrical outputs, and a bootstrapped high-side gate driver. Several passive technologies were investigated for both control and power sections. Capacitor technologies were characterized over temperature and over time at 300CÃ¢ÂˆÂ˜, power inductors designed and tested up to 350CÃ¢ÂˆÂ˜, and power transformers designed and tested up to 500CÃ¢ÂˆÂ˜. Northrop Grumman normally-off SiC JFETs were used as power switches and were characterized up to 250CÃ¢ÂˆÂ˜. Efficiency and mass optimization routines were developed with the data gained from the first prototype. The effects of radiation on SiC and SOI electronics are then discussed. The results of the first prototype module are presented, with operation from 25CÃ¢ÂˆÂ˜ up to an ambient temperature of 240CÃ¢ÂˆÂ˜ .
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.
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
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...
National Aeronautics and Space Administration — Studying and analyzing the ageing mechanisms of electronic components avionics in systems such as the GPS and INAV are of critical importance. In DC-DC power...
Digitally intensive DC-DC converter for extreme space environments Project
National Aeronautics and Space Administration — The Space Micro Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator...
Directory of Open Access Journals (Sweden)
Liao Xiaozhong
2013-02-01
Full Text Available High Output Voltage Based Multiphase Step-Up DC-DC Converter topology with voltage doubler rectifiers is presented in this paper. High output voltage is obtained due to the series combination of voltage doubler rectifiers on the secondary side of high frequency transformers. This topology is useful in the application where the output voltage is greater than the input. The two loop control strategy has been developed in order to analyze the stable and effective working of the converter topology. Therefore the working mode analysis of the converter topology has been described in detail. The multiphase step-up DC-DC converter topology is first simulated on MATLAB and then a prototype has been designed in order to verify the simulation and experimental results. Finally the simulation and experimental results are found to be satisfactory.
Evaluating neural control with optimal architecture for DC/DC converter
Directory of Open Access Journals (Sweden)
Fredy Hernán Martínez Sarmiento
2010-05-01
-power equipment raises great design challenges due to the mathematical model’s complexity and its highly nonlinear dynamic characteristics. Artificial intelligence techniques, such as neuronal networks, suppose great improvements in design and final per- formance, given their capacity for learning complex dynamics and generalising their behaviour. This work was aimed at propo- sing (and evaluating dynamic response later on direct control link with neuronal networks which also allowed eliminating test ele- ments and error in its design. Artificial neuronal network-based direct control was designed as well as possible using bio-inspired search models. This simultaneously optimised two different but fundamental aspects of the network: architecture and the weight of the connections. The control was applied to a boost converter. The results led to observing the scheme’s dynamic performan- ce; response time and exit voltage delta led to concluding that the criteria selected for designing the control were appropriate and represented a contribution towards developing control applications of DC/DC switchmode systems.
Design of piezoelectric transformer for DC/DC converter with stochastic optimization method
Vasic, Dejan; Vido, Lionel
2016-04-01
Piezoelectric transformers were adopted in recent year due to their many inherent advantages such as safety, no EMI problem, low housing profile, and high power density, etc. The characteristics of the piezoelectric transformers are well known when the load impedance is a pure resistor. However, when piezoelectric transformers are used in AC/DC or DC/DC converters, there are non-linear electronic circuits connected before and after the transformer. Consequently, the output load is variable and due to the output capacitance of the transformer the optimal working point change. This paper starts from modeling a piezoelectric transformer connected to a full wave rectifier in order to discuss the design constraints and configuration of the transformer. The optimization method adopted here use the MOPSO algorithm (Multiple Objective Particle Swarm Optimization). We start with the formulation of the objective function and constraints; then the results give different sizes of the transformer and the characteristics. In other word, this method is looking for a best size of the transformer for optimal efficiency condition that is suitable for variable load. Furthermore, the size and the efficiency are found to be a trade-off. This paper proposes the completed design procedure to find the minimum size of PT in need. The completed design procedure is discussed by a given specification. The PT derived from the proposed design procedure can guarantee both good efficiency and enough range for load variation.
Total ionizing dose effects of DC-DC power converter used in satellite
International Nuclear Information System (INIS)
The total ionizing dose effects and annealing effects of DVHF2812DF and DVTR2815DF DC-DC power converters were investigated. The typical electrical parameters, such as input current, output current, output voltage, and input current of inhibition mode, as functions of the total dose with different loads and different input voltages were discussed. The relationships between these parameters and the annealing time were observed. The experiment results show that when annealing at room temperature, the trapped holes in deeper energy levels anneal little, which results in dramatic changes of the electric parameters of the DVHF2812DF device when irradiated with extra dose irradiation. However, these parameters go back to the initial values when annealing at high temperature. There are more changes of the electric parameters under the full power loaded situation than other conditions. The input current under inhibition mode can be considered as a sensitive parameter in the evaluation of the radiation-hardened levels of the devices. (authors)
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.
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.
Directory of Open Access Journals (Sweden)
Haojie Wang
2016-07-01
Full Text Available It is a common practice for storage batteries to be connected to DC microgrid buses through DC-DC converters for voltage support on islanded operation mode. A feed-forward control based dual-loop constant voltage PI control for three-branch interleaved DC-DC converters (TIDC is proposed for storage batteries in DC microgrids. The working principle of TIDC is analyzed, and the factors influencing the response rate based on the dual-loop constant voltage control for TIDC are discussed, and then the method of feed-forward control for TIDC is studied to improve the response rate for load changing. A prototype of the TIDC is developed and an experimental platform is built. The experiment results show that DC bus voltage sags or swells caused by load changing can be reduced and the time for voltage recovery can be decreased significantly with the proposed feed-forward control.
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.
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.; Maksimovic, Dragan; Sarban, Rahimullah
2014-01-01
This paper presents the design of a low input (24 V) and variable high output voltage (0-2.5 kV) bidirectional dc-dc converter for driving a capacitive actuator. The topology is a digitally controlled bidirectional flyback converter with a variable frequency control. The objective is, to design the converter for efficiently charging and discharging the capacitive actuator from 0 V to 2.5 kV and vice versa, respectively. The converter is used to drive a dielectric electro active polymer (DEAP)...
Efficiency and Cost Comparison of Si IGBT and SiC JFET Isolated DC/DC Converters
DEFF Research Database (Denmark)
Nielsen, Rasmus Ørndrup; Török, Lajos; Munk-Nielsen, Stig;
2013-01-01
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. The hardware differences between the two converters are described and performance is compared. An...... 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....
Using Nyquist or Nyquist-Like Plot to Predict Three Typical Instabilities in DC-DC Converters
Fang, Chung-Chieh
2012-01-01
By transforming an exact stability condition, a new Nyquist-like plot is proposed to predict occurrences of three typical instabilities in DC-DC converters. The three instabilities are saddle-node bifurcation (coexistence of multiple solutions), period-doubling bifurcation (subharmonic oscillation), and Neimark bifurcation (quasi-periodic oscillation). In a single plot, it accurately predicts whether an instability occurs and what type the instability is. The plot is equivalent to the Nyquist...
A.S. Oshaba; E.S. Ali
2013-01-01
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 co...
Implementation of Rapid Prototyping Tools for Power Loss and Cost Minimization of DC-DC Converters
Directory of Open Access Journals (Sweden)
Amruta V. Kulkarni
2016-07-01
Full Text Available In this paper, power loss and cost models of power electronic converters based on converter ratings and datasheet information are presented. These models aid in creating rapid prototypes which facilitate the component selection process. Through rapid prototyping, users can estimate power loss and cost which are essential in design decisions. The proposed approach treats main power electronic components of a converter as building blocks that can be arranged to obtain multiple topologies to facilitate rapid prototyping. In order to get system-level power loss and cost models, two processes are implemented. The first process automatically provides minimum power loss or cost estimates and identifies components for specific applications and ratings; the second process estimates power losses and costs of each component of interest as well as the whole system. Two examples are used to illustrate the proposed approaches—boost and buck converters in continuous conduction mode. Achieved cost and loss estimates are over 93% accurate when compared to measured losses and real cost data. This research presents derivations of the proposed models, experimental validation of the models and demonstration of a user friendly interface that integrates all the models. Tools presented in this paper are expected to be very useful for practicing engineers, designers, and researchers, and are flexible and adaptable with changing or new technologies and varying component prices.
DEFF Research Database (Denmark)
Park, Kiwoo; Chen, Zhe
2015-01-01
have several advantages for high-power applications, and the modular concept of the parallel-connected converter is highly beneficial especially for offshore wind farm applications in terms of maintenance cost and fault tolerance. To justify the feasibility of the parallel-connected SAB dc-dc converter......This study presents a control strategy and its dynamic analysis of a high-power dc-dc converter, which is constructed with the parallel-connected single active bridge (SAB) dc-dc converters for dc-grid wind farm applications. The structural and operational characteristics of the SAB dc-dc converter...... for dc-grid wind farm applications, an input voltage control method based on the PI control will be introduced and the dynamics of the overall system will be analysed. The analysis results are to be verified by means of simulations and experiments....
Topology investigation of front end DC/DC converter for distributed power system
Yang, Bo
2003-01-01
Topology Investigation of Front End DC/DC Power Conversion for Distributed Power System by Bo Yang Fred C. Lee, Chairman Electrical Engineering (Abstract) With the fast advance in VLSI technology, smaller, more powerful digital system is available. It requires power supply with higher power density, lower profile and higher efficiency. PWM topologies have been widely used for this application. Unfortunately, hold up time requirement put huge penalties on the performance o...
Directory of Open Access Journals (Sweden)
Taizhou Bei
2014-01-01
Full Text Available Considering the disadvantages of the traditional high-gain DC-DC converter such as big size, high voltage stress of switches, and large input current ripple, a novel high-gain interleaved boost converter with coupled-inductor and switched-capacitor was proposed correspondingly and the operation principle together with the steady-state analysis of this converter was also described. Besides, a new control approach-dynamic sliding mode evolution PWM controller (DSME PWM for the novel topological converter based on both dynamic evolution and sliding mode control was also presented. From the simulation results and experimental validation the proposed converter can fulfill high-gain boost, low ripple of both the input current and the output voltage. Furthermore, MPPT technique can be also achieved in a short time by simulation. The efficiency and stability of the converter proposed in this paper can be improved.
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.
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.
DEFF Research Database (Denmark)
Meng, Lexuan; Dragicevic, Tomislav; Quintero, Juan Carlos Vasquez;
2015-01-01
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......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...
V. V. Subrahmanya Kumar Bhajana; S. Rama Reddy
2010-01-01
A closed loop ZVS-ZCS bidirectional dc-dc converter is modeled and appropriate digital simulations are provided. With the ZVS-ZCS concept, the MATLAB simulation results of application to a fuel cell and battery application have been obtained whenever the input voltage exceeds the given 24V, at that time the load voltage will change from 180V to 230V. But due to this usage the load is disturbed and there is instability in the model. Using closed loop the output voltage is stabilized.
Directory of Open Access Journals (Sweden)
V. V. Subrahmanya Kumar Bhajana
2010-08-01
Full Text Available A closed loop ZVS-ZCS bidirectional dc-dc converter is modeled and appropriate digital simulations are provided. With the ZVS-ZCS concept, the MATLAB simulation results of application to a fuel cell and battery application have been obtained whenever the input voltage exceeds the given 24V, at that time the load voltage will change from 180V to 230V. But due to this usage the load is disturbed and there is instability in the model. Using closed loop the output voltage is stabilized.
A Novel Dual-input Isolated Current-Fed DC-DC Converter for Renewable Energy System
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.;
2010-01-01
In this paper, a novel isolated current-fed DC-DC converter (boost-type) with two input power sources based on multi-transformer structure, which is suitable for fuel cells and super-capacitors hybrid energy system, is proposed and designed. With particular transformer windings connection strategy......, the proposed converter can draw power from two different DC sources with lower voltage and deliver it to the higher voltage DC bus or load individually and simultaneously. The detailed operation principle of the proposed converter has been analyzed in dual-input mode and single-input mode......, respectively. Furthermore, the method to increase the number of input ports, the magnetic integration structure, and ground loop decoupling are discussed. Experimental results from the lab prototype converter with two DC voltage sources verify the validity of the theoretical analysis and design of the...
SPECTRAL ANALYSIS OF BUCK AND SEPIC CONVERTERS
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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)
Boumediène Allaoua
2013-01-01
Full Text Available The development of electric vehicles power electronics system control comprising of DC-AC inverters and DC-DC converters takes a great interest of researchers in the modern industry. A DC-AC inverter supplies the high power electric vehicle motors torques of the propulsion system and utility loads, whereas a DC-DC converter supplies conventional low-power, low-voltage loads. However, the need for high power bidirectional DC-DC converters in future electric vehicles has led to the development of many new topologies of DC-DC converters. Nonlinear control of power converters is an active area of research in the fields of power electronics. This paper focuses on a fuzzy sliding mode strategy (FSMS as a control strategy for boost DC-DC converter power supply for electric vehicle. The proposed fuzzy controller specifies changes in the control signal based on the surface and the surface change knowledge to satisfy the sliding mode stability and attraction conditions. The performances of the proposed fuzzy sliding controller are compared to those obtained by a classical sliding mode controller. The satisfactory simulation results show the efficiency of the proposed control law which reduces the chattering phenomenon. Moreover, the obtained results prove the robustness of the proposed control law against variation of the load resistance and the input voltage of the studied converter.
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 theoretical–phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as heat generation increases the losses. In our design, the maximum output current capacity can increase by 100% when the temperature of operation of the PT is kept below 55 ° C. The study comprises a theoretical part and experimental proof-of-concept demonstration of the proposed design method. (paper)
Su, Yu-Hao; Liu, Yuan-Ping; Vasic, Dejan; Costa, Francois; Wu, Wen-Jong; Lee, Chuih-Kung
2013-09-01
The objective of this study was to increase the output current and power in a piezoelectric transformer (PT)-based DC/DC converter by using a cooling system. It is known that the output current of a PT is limited by temperature build-up because of losses, especially when driving at high vibration velocity. Although connecting different inductive circuits at the PT secondary terminal can increase the output current, the root cause of the temperature build-up problem has not yet been solved. This paper presents a study of a PT with cooling system in a DC/DC converter with a commonly used full-bridge rectifier and current-doubler rectifier. The advantages and disadvantages of the proposed technique were investigated. A theoretical-phenomenological model was developed to explain the relationship between the losses and the temperature rise. It will be shown that the vibration velocity as well as heat generation increases the losses. In our design, the maximum output current capacity can increase by 100% when the temperature of operation of the PT is kept below 55 ° C. The study comprises a theoretical part and experimental proof-of-concept demonstration of the proposed design method.
Modeling and Control of DC/DC Boost Converter using K-Factor Control for MPPT of Solar PV System
DEFF Research Database (Denmark)
Vangari, Adithya; Haribabu, Divyanagalakshmi; Sakamuri, Jayachandra N.
2015-01-01
This paper is focused on the design of a controller for the DC/DC boost converter using K factor control, which is based on modified PI control method, for maximum power point tracking (MPPT) of solar PV system. A mathematical model for boost converter based on small signal averaging approach is...... presented. Design of the passive elements of the boost converter as per the system specifications is also illustrated. The performance of the proposed K factor control method is verified with the simulations for MPPT on solar PV system at different atmospheric conditions. A new circuit based model for solar...... PV array, which includes the effect of solar insolation and temperature on PV array output, for the application in power system transient simulations, is also presented. The performance of the PV array model is verified with simulations at different atmospheric conditions. A 160W PV module from BP...
DEFF Research Database (Denmark)
Török, Lajos; Munk-Nielsen, Stig
2011-01-01
A comparison of an analog and a digital controller driven 70 W two-stage power factor corrector converter is presented. Both controllers are operated in average current-mode-control for the PFC and peak current control for the DC-DC converter. Digital controller design and converter modeling is...
Development of a DC-DC conversion powering scheme for the CMS Phase-1 pixel upgrade
Feld, Lutz Werner; Karpinski, Waclaw; Klein, Katja; Lipinski, Martin; Preuten, Marius; Max Rauch; Rittich, David Michael; Sammet, Jan Domenik; Wlochal, Michael
2014-01-01
A novel powering scheme based on the DC-DC conversion technique will be exploited to power the CMS Phase-1 pixel detector. DC-DC buck converters for the CMS pixel project have been developed, based on the AMIS5 ASIC designed by CERN. The powering system of the Phase-1 pixel detector is described and the performance of the converter prototypes is detailed, including power efficiency, stability of the output voltage, shielding, and thermal management. Results from a test of the magnetic field tolerance of the DC-DC converters are reported. System tests with pixel modules using many components of the future pixel barrel system are summarized. Finally first impressions from a pre-series of 200 DC-DC converters are presented.
DC/DC开关变换器混沌现象研究综述%Summary of the Research on Chaos Phenomena of DC/DC Converter
Institute of Scientific and Technical Information of China (English)
蔚洋; 冯平
2012-01-01
DC/DC功率开关变换器是开关电源的核心部分,通过对其混沌现象的研究可以更加深刻地认识DC/DC变换器的本质,也会在将来基于混沌现象提出新的设计方法和控制策略,实现现有DC/DC变换器无法达到的性能.本文介绍了DC/DC变换器混沌现象的研究现状,对DC/DC变换器混沌现象的基本建模方法进行了综合对比分析,展望了DC/DC变换器混沌研究的发展和未来应用前景.%DC/DC power switch converter is the core part of switch power supply. Through the study of chaos phenomena, the essence of DC/DC converter can be more deeply understand, the new design methods and control strategies based on chaos phenomena will be put forward in the future, to achieve the existing DC/DC converter that cannot reach. This paper introduces the research status of the DC/DC converter chaos phenomena, makes comprehensive comparative analysis of the basic modeling method of DC/DC converter chaos phenomena, and looks to its development and future application prospect.
SUPPRESSING CONDUCTED EMI FROM A DC/DC HIGH POWER CONVERTER BASED ON MIXED-MODE FILTER
Institute of Scientific and Technical Information of China (English)
无
2005-01-01
Conducted electromagnetic interference (EMI) from a 7.5kVA DC/DC high power converter is investigated to agree with EN class A. Here in some passive methods of suppressing conducted EM Noise, such as mixed-mode (MM) EMI filters, snubbing circuits and other means, are used. Based on measurement, the sources of noise are detected with the characteristics analyzed in detail. The MM EMI filters is valuable means with which low-frequency part and some of the high frequency part of conducted EM Noise can be efficiently reduced. How to lay out the MM filters on both sides of the converter is outlined in detail. In addition, multiple grounding and RDC snubbing circuits are employed to improve the performance in high frequency. The experimental results confirm the methods adopted.
Simple digital PWM and PSM controlled DC-DC boost converter for luminance-regulated WLED driver
Institute of Scientific and Technical Information of China (English)
LIU Xin; GUO Shu-xu; CHANG Yu-chun; ZHU Shun-dong; WANG Shuai
2009-01-01
This article presents a control strategy based on simple digital pulse-width modulation (DPWM) and pulse-skip modulation (PSM) for a DC-DC boost converter, to drive a luminance-regulated white light emitting diodes (WLEDs). The presented control strategy not only retains most of the advantages and flexibilities of traditional digital PWM, but also reduces complexity and cost. Based on analyzing the principle of the presented control strategy, the white light emitting diode (WLED) driver is designed and simulated using the 0.6 (m CMOS process. Simulation results of the boost converter show that the power efficiency is above 76% for a full load, with a peak efficiency of 88% when supply voltage varies from 2.7 V to 5.5 V. The control strategy overcomes low efficiency for PWM mode with light load.
三重交错并联DC／DC变换器设计%Design of a triple interleaving DC/DC converter of composite power electric cars
Institute of Scientific and Technical Information of China (English)
张智林; 张彦会; 张群
2012-01-01
DC／DC变换器是复合电源电动汽车的重要组成部分之一，为了提高DC／DC变换器的功率密度，DC／DC变换器正在向高频化发展，研究在单相DC／DC变换器的基础上，设计了一种三重交错并联DC／DC变换器，可以提高系统的开关频率、降低纹波电压，从而减小滤波器的体积、提高功率密度．最后通过Simulink进仿真分析，结果表明：三重交错并联DC／DC变换器的纹波电压明显小于单相DC／DC变换器，有利于功率密度的提高．%DC/DC converter is the important part of composite power electric cars. In order to improve the power density of DC/DC converter, high frequency is required. This paper designs a triple inter/earing DC/DC converter based on the single phase DC/DC converter. It can reduce the ripple voltage effectively, reduce the volume of the filter and improve the switch frequency of the system. Finally, through the simulation analysis, the results show that the system efficiency of the triple interleaving DC/DC converter is better than the single phase DC/DC converter, thus the power density is increased.
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.
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 ...
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...... perpendicular primary windings, a name of “four quadrants integrated transformers” (FQIT) is therefore given to the proposed construction. Since the two primary windings are uncoupled, the FQIT allows the two input power stages to transfer the energy into the output load simultaneously or at any...... timemultiplexing scheme, which can optimize the utilization of diversified power energy sources, simplify the system structure, improve the flexibility and reduce the overall cost, so they are attractive for the hybrid renewable power system. Section IV initiates a discussion for the advantages of the FQIT. In...
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
DEFF Research Database (Denmark)
Zhang, Zhe; Ouyang, Ziwei; Thomsen, Ole Cornelius;
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...
Faccio, F; Michelis, S; Faccio, Federico; Fuentes, C; Allongue, B; Sorge, R; Orlandi, S
2010-01-01
TID and displacement damage effects are studied for vertical and lateral power MOSFETs in five different technologies in view of the development of radiation-tolerant fully integrated DC-DC converters. Investigation is pushed to the very high level of radiation expected for an upgrade to the LHC experiments. TID induces threshold voltage shifts and, in n-channel transistors, source-drain leakage currents. Wide variability in the magnitude of these effects is observed. Displacement damage increases the on-resistance of both vertical and lateral high-voltage transistors. In the latter case, degradation at high particle fluence might lead to a distortion of the output characteristics curve. HBD techniques to limit or eliminate the radiation-induced leakage currents are successfully applied to these high-voltage transistors, but have to be used carefully to avoid consequences on the breakdown voltage.
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
Self-oscillating Galvanic Isolated Bidirectional Very High Frequency DC-DC Converter
DEFF Research Database (Denmark)
Pedersen, Jeppe Arnsdorf; Madsen, Mickey Pierre; Knott, Arnold;
2015-01-01
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......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...... 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....
Two-output Class E Isolated dc-dc Converter at 5 MHz Switching Frequency
Pavlovic, Zoran; Oliver Ramírez, Jesús Angel; Alou Cervera, Pedro; García Suárez, Oscar; Prieto López, Roberto; Cobos Márquez, José Antonio
2010-01-01
This paper presents a two output class-E isolated dcdc converter that regulates the output voltages at fixed switching frequency. The converter is simulated at operating frequency of 5 MHz. The converter output power is 40 W and the output voltages are 15 V and 5 V. All the switches operate at zero voltage switching (ZVS) conditions for the full load range. The circuit configuration is simple with small passive components which reduce the size of the converter. The circuit also has ...
A novel resonant transition push-pull DC-DC converter
Swaminathan, B.; Ramanarayanan, V
2004-01-01
In hard-switched converters, the switching frequency is limited by switching losses and EMI problems. However, high-switching frequency is necessary to reduce the converter size. Hence, soft switching is imperative at high switching frequency to obtain good efficiency. Push-pull converter is a preferred topology at medium power level. This paper proposes a novel resonant transition topology for push-pull converter. The proposed topology uses two additional switches and two diodes when compare...
New DC/DC High Step Up Isolated Converter with ZVS
Directory of Open Access Journals (Sweden)
Ehsan Movahedi
2014-10-01
Full Text Available In this paper we presents a soft switch sepic, flyback converter. At first the converter have hard switching in main switch and completely analysis then added auxiliary circuit for soft switching Auxiliary circuit in the converter is not only soft switching condition for the main switch but also prevents the spike voltage across the main switch when turned off that because leakage inductance. Therefore, the proposed converter efficiency in comparison with the previous converters increased and voltage stress on the main switch is reduced. Also the auxiliary switch in the converter have soft switching and thereby decrese losses. this converter Control with pwm.These converter have higher efficiency than the similar converters and the cost is low. Auxiliary circuit in the converter is not only soft switching condition for the main switch but also prevents the spike voltage across the main switch when turned off that because leakage inductance. Therefore, the proposed converter efficiency in comparison with the previous converters increased and voltage stress on the main switch is reduced.
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.
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.
A New Soft Switching Current fed DC-DC Converter for Medium Power Applications
Directory of Open Access Journals (Sweden)
Majid Delshad
2008-09-01
Full Text Available In this paper a new zero voltage switching current fed half bridge converter with an auxiliary circuit is proposed. The auxiliary circuit not only absorbs the voltage surge across switches at turn off instance, but also provides zero voltage switching condition for all converter switches. Therefore in this converter the efficiency is higher than hard switching counterpart and also main switches voltage stresses decrease. Since the switches in auxiliary circuit operate under soft switching conditions, these switches don’t apply additional losses to proposed converter. Implementation of control circuit is very simple since the converter is PWM controlled and the auxiliary switches turn on are complementary with respect to main switches. In this paper the proposed converter operating modes are analyzed and simulation results are presented. To verify the converter operation a 100W laboratory prototype operating at 100kHz is implemented and the experimental results are presented.
Isolated DC-DC UPS based in a forward-forward converter analysis and design
García Suárez, Oscar; Flores Oropeza, Luis Alejandro; Román Loera, Alejandro; Esparza González, Mario S.
2008-01-01
This paper presents the analysis, design and simulation from a simple DC-UPS converter with integrated back-up and automatic transition. This converter makes automatic transition between the main AC and the battery when a failure occurs, and it delivers uninterrupted DC power to the load through two independent power sources of commercial input power and battery power. The converter has the following characteristics: automatic transition between the main and the battery, no additional control...
A New Soft Switching Current fed DC-DC Converter for Medium Power Applications
Majid Delshad
2008-01-01
In this paper a new zero voltage switching current fed half bridge converter with an auxiliary circuit is proposed. The auxiliary circuit not only absorbs the voltage surge across switches at turn off instance, but also provides zero voltage switching condition for all converter switches. Therefore in this converter the efficiency is higher than hard switching counterpart and also main switches voltage stresses decrease. Since the switches in auxiliary circuit operate under soft switching con...
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.
DEFF Research Database (Denmark)
Schaltz, Erik; Li, Zhihao; Onar, Omer;
2009-01-01
Battery/Ultra-capacitor based electrical vehicles (EV) combine two energy sources with different voltage levels and current characteristics. This paper focuses on design and control of a multiple input DC/DC converter, to regulate output voltage from different inputs. The proposed multi...
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...
A Two-stage DC-DC Converter for the Fuel Cell-Supercapacitor Hybrid System
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2009-01-01
A wide input range multi-stage converter is proposed with the fuel cells and supercapacitors as a hybrid system. The front-end two-phase boost converter is used to optimize the output power and to reduce the current ripple of fuel cells. The supercapacitor power module is connected by push......-pull-forward half bridge (PPFHB) converter with coupled inductors in the second stage to handle the slow transient response of the fuel cells and realize the bidirectional power flow control. Moreover, this cascaded structure simplifies the power management. The control strategy for the whole system is analyzed and...
A Two-stage DC-DC Converter for the Fuel Cell-Supercapacitor Hybrid System
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2009-01-01
A wide input range multi-stage converter is proposed with the fuel cells and supercapacitors as a hybrid system. The front-end two-phase boost converter is used to optimize the output power and to reduce the current ripple of fuel cells. The supercapacitor power module is connected by push-pull-forward half bridge (PPFHB) converter with coupled inductors in the second stage to handle the slow transient response of the fuel cells and realize the bidirectional power flow control. Moreover, this...
Dynamic characteristics of DC-DC converter with novel digital peak current-injected control
Kurokawa, Fujio; Sakemi, Junya; Sukita, Shohei; Shibata, Yuichiro; Soejima, Masato; YOKOYAMA, Tomonori; Sasaki, Masahiro; Mimura, Yasuhiro
2009-01-01
This paper presents the dynamic characteristics of the proposed digital control current mode de-de converter. In the proposed novel digital control circuit, the peak current-injected control is realized using the combination of the simple dual A-Dsignal converter and the programmed delay circuit. In 100kHz digitally controlled de-de converter, it is seen in simulation that the proposed method has no overshoot of the output voltage and the convergencetime that the output voltage is settled to ...
Chih-Lung Shen; Hong-Yu Chen; Po-Chieh Chiu
2015-01-01
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...
Analysis, design and implementation of an interleaved three-level PWM DC/DC ZVS converter
Lin, Bor-Ren; Liu, Chien-Hung
2016-02-01
This paper presents a new parallel three-level soft switching pulse-width modulation (PWM) converter. The proposed converter has two circuit cells operated by the interleaved PWM modulation. Thus, the ripple currents at input and output sides are reduced. Each circuit cell has two three-level zero voltage switching circuits sharing the same power switches. Therefore, the current and power rating of the secondary side components are reduced. Current double rectifier topology is selected on the secondary side to decrease output ripple current. The main advantages of the proposed converter are soft switching of power switches, low ripple current on the output side and low-voltage rating of power switches for medium-power applications. Finally, the performance of the proposed converter is verified by experiments with 1 kW prototype circuit.
Design of discrete time controllers for the DC-DC boost converter
Directory of Open Access Journals (Sweden)
Mohammed Alkrunz
2016-04-01
Full Text Available In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried out.
Design of discrete time controllers for the DC-DC boost converter
Mohammed Alkrunz; Irfan Yazıcı
2016-01-01
In this paper, a small signal model for the boost converter is obtained. Two digital controllers using pole placement technique and Linear Quadratic Optimal Regulator (LQR) methods are designed and applied to the boost converter. The compensated system’s operations and analysis are discussed and verified through MATLAB/Simulink simulation. Comparison between the two controllers related to the design methodology, implementation issues and transient measured performance is carried o...
Two-Phase Interleaved Buck Converter with a new Digital Self-Oscillating Modulkator
DEFF Research Database (Denmark)
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2007-01-01
This paper presents a new Digital Self-Oscillating Modulator (DiSOM) for DC/DC converters. The DiSOM modulator alllows the digital control algorithm to sample the output voltage at a sampling frequency higher than the converter switching frequency. This enables higher control loop bandwidth than...... for traditional digital PWM modulators given a certain switching frequency. A synchronised version of the DiSOM modulator is derived for interleaved converters. A prototype interleaved Buck converter for Point of Load applications has been designed and built to test the performance of DiSOM modulator....... The DiSOM modulator and a digital control algorithm have been implemented in an FPGA. Experimental results show that the converter has a very fast transient response when a loadstep is applied to the output. For a loadstep of 50% of nominal output current the output voltage overshoot is less than 2...
Directory of Open Access Journals (Sweden)
Slamet Kasbi
2015-12-01
Full Text Available Boost DC-DC converters are used in many renewable energy sources including photovoltaic and fuel cell. They are also used in Uninterrupted Power Supply, inverters, electric vehicles and robots. In this paper a boost converter was built and its controller was developed using proportional integral (PI action for current loop and low pass filter (LPF for voltage loop. The controller was derived analytically based on small signal model. Experiment results show that the boost controller functions well in regulating the output voltage under a variation of load. During the start up without any load it can elevate input voltage from 119.6V to output voltage of 241.6V. The developed controller can regulate the output voltage smoothly under load variation from no load to sudden load of 352W. When a large sudden load change happens from 0W to 1042W the output voltage experiences small drop before it is recovered to 241.6V. It can be concluded that the developed control system satisfies the design specification.
DEFF Research Database (Denmark)
Thummala, Prasanth; Maksimovic, Dragan; Zhang, Zhe;
2016-01-01
(0-2.5 kV) bidirectional dc-dc flyback converter for driving a capacitive incremental actuator. The incremental actuator consists of three electrically isolated, mechanically connected capacitive actuators. It requires three high voltage (2-2.5 kV) bidirectional dc-dc converters, to accomplish the...... incremental motion by charging and discharging the capacitive actuators. The bidirectional flyback converter employs a digital controller to improve efficiency and charge/discharge speed using the valley switching technique during both charge and discharge processes, without the need to sense signals on the...... output high-voltage (HV) side. Experimental results verifying the bidirectional operation of a high voltage flyback converter are presented, using a 3 kV polypropylene film capacitor as the load. The energy loss distributions of the converter when 4 kV and 4.5 kV HV MOSFETs are used on HV side are...
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)
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.
Reliability-Oriented Design of LC Filter in Buck DC-DC Converter
DEFF Research Database (Denmark)
Liu, Yi; Huang, Meng; Wang, Huai; Zha, Xiaoming; Gong, Jinwu; Sun, Jianjun
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...
Directory of Open Access Journals (Sweden)
Nittala S K Sastry
2012-06-01
Full Text Available This paper presents a new PWM Multi phase DC-DC converter under current mode control with an auxiliary circuit which provides zero voltage switching in order to meet the power supply requirements of the processors of modern electronic equipments like laptops, mobiles, and PDAs etc which require more than 70 A current, lower voltage and better transient response.The multi phase topology benefits in high current, good efficiency and better current transient response. High current multi phase buck converters found applications in advanced data control, solid state lasers, communication equipment and Pentium processors etc. In this paper designed of three phase DC-DC converter 100W, 12V/1V under current mode control is discussed in detail and the simulation results are presented to support the theoretical analysis.
Observer design for DC/DC power converters with bilinear averaged model
Spinu, V.; Dam, M.C.A.; Lazar, M.
2012-01-01
Increased demand for high bandwidth and high efficiency made full state-feedback control solutions very attractive to power-electronics community. However, full state measurement is economically prohibitive for a large range of applications. Moreover, state measurements in switching power converters
High-voltage boost quasi-Z-source isolated DC/DC converter
DEFF Research Database (Denmark)
Siwakoti, Yam P.; Blaabjerg, Frede; Loh, Poh Chiang;
2014-01-01
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...
High Efficiency Non-isolated Three Port DC-DC Converter for PV-Battery Systems
DEFF Research Database (Denmark)
Tomas Manez, Kevin; Anthon, Alexander; Zhang, Zhe;
2016-01-01
This paper presents a nonisolated Three Port Converter (TPC) with a unidirectional port for photovoltaic (PV) panels and a bidirectional port for energy storage. With the proposed topology single power conversion is performed between each port, so high efficiencies are obtained. A theoretical...
Research on control algorithm of DC-DC Boost converters%DC-DC Boost变换器控制算法的研究
Institute of Scientific and Technical Information of China (English)
杨玉岗; 甘汶桦
2015-01-01
为了改善DC⁃DC Boost变换器的性能，在电压控制模式的基础上，设计了PI控制器，对输出电压进行控制。分析了DC⁃DC Boost变换器的基本原理，推导了变换器的传递函数。本文用Zie⁃gler⁃Nichols方法和Loop⁃Shaping方法计算出PI控制器中K p和K i的值，进而通过Matlab仿真和实验，比较了两种方法的输出响应，得出结论：采用Loop⁃Shaping方法能更好改善变换器的性能。%To improve the control performance of DC⁃DC Boost power converters, a PI controller is designed to reg⁃ulate the output voltage based on voltage mode. The basic principle of the DC⁃DC Boost converter have been ana⁃lyzed, and the transfer function of the converter have been derived. The paper uses PI controller in which the val⁃ues of Kp and Ki have been derived using the Ziegler⁃Nichols method and Loop Shaping method, and through Matlab simulation and experiment, the output response of the both methods is compared and conclusion is made that Loop⁃Shaping method can improve the performance of the converter better.
National Aeronautics and Space Administration — The Space Micro ?Arizona State University (ASU) team will develop an all-digitally controlled, wide temperature range point-of-load switch-mode DC-DC regulator core...
Soft Switching Full-Bridge PWM DC/DC Converter Using Secondary Snubber
Directory of Open Access Journals (Sweden)
Jaroslav Dudrik
2009-05-01
Full Text Available A novel full-bridge PWM DC/DCconverter with controlled secondary side rectifier usingsecondary snubber is presented in this paper.Limitation of the circulating current as well as softswitching for all power switches of the inverter isachieved for full load range from no-load to shortcircuit by using controlled rectifier and snubber on thesecondary side. Phase shift PWM control strategy isused for the converter. The principle of operation isexplained and analyzed and the experimental resultson a 1kW, 50 kHz laboratory model of the converterare presented.
Generalized computer-aided discrete time domain modeling and analysis of dc-dc converters
Lee, F. C.; Iwens, R. P.; Yu, Y.; Triner, J. E.
1977-01-01
A generalized discrete time domain modeling and analysis technique is presented for all types of switching regulators using any type of duty-cycle controller, and operating in both continuous and discontinuous inductor current. State space techniques are employed to derive an equivalent nonlinear discrete time model that describes the converter exactly. The system is linearized about its equilibrium state to obtain a linear discrete time model for small signal performance evaluations, such as stability, audiosusceptibility and transient response. The analysis makes extensive use of the digital computer as an analytical tool. It is universal, exact and easy to use.
A Different Three-Port DC/DC Converter for Standalone PV System
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Nimrod Vázquez
2014-01-01
Full Text Available A three-port converter suitable for standalone applications is proposed in this paper. Each port is used for specific input or output, and its functions depend on the port; they are the renewable source, the battery set, and the output port. This proposed converter is considered for standalone operation, but it is not limited to it. Not only the system is able to deliver energy independently from each input source or in a mixed way for the output, but also the battery system may be charged from the renewable source just in case it is required. The battery port is only used when it is required; this allows increasing battery lifetime. Another important feature is that, in case of a renewable source failure, the energy is automatically demanded from the battery set, like an uninterruptible power supply. The system is able to track the maximum power of the renewable source when it is required. Operation, analysis, simulation, and experimental results are described in detail.
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%.
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...
Institute of Scientific and Technical Information of China (English)
吴云亚; 谢少军; 阚加荣; 汤雨
2014-01-01
根据导抗网络的基本特性，提出一种新型双向直流变换器(bidirectional DC/DC converter，BDC)。分析了所提双向变换器在 boost 模式和 buck 模式下电路的工作模态。由导抗网络的基本特性可知，在任意的工作模式下，都可保证变换器中全桥变换器交流侧的功率因数为1，可使回流功率为零以提高系统效率。分析了双向变换器中的物理量关系，给出了变换器中变压器、导抗网络参数优化设计的规则，提出了双向变换器的信号调制策略及相应控制策略。实验结果表明所提BDC性能优良。%According to basic characteristic of immittance network, a structure for a new type of bidirectional DC/DC (BDC) converter is proposed. The operating modals of the circuit of the proposed BDC converter under boost mode and buck mode are analyzed. It can be seen from basic characteristic of immittance network that under arbitrary working mode the power factor at the AC side of the full-bridge converter in the BDC converter can be ensured as unity, thus it makes the backflow becoming zero to improve the system efficiency. The relation among physical quantities in the proposed BDC converter is analyzed and the rules for optimization design of parameters of transformer and immittance network of the proposed BDC converter are given. The signal modulation strategy of the BDC converter and corresponding control strategy are put forward. Experimental results show that the proposed BDC converter possesses high performance.
DEFF Research Database (Denmark)
Park, Kiwoo; Chen, Zhe
2013-01-01
This paper presents a parallel-connected Single Active Bridge (SAB) dc-dc converter for high-power applications. Paralleling lower-power converters can lower the current rating of each modular converter and interleaving the outputs can significantly reduce the magnitudes of input and output current...... ripples without increasing switching losses or device stresses. Analysis of both the input and output current characteristics and design aspects of the transformer, the filter inductor, and the input and output filter capacitors will be presented. Considering the high maintenance cost and fault tolerant...... requirements, this modular converter concept is expected to be highly beneficial especially for the offshore wind farm application....
Directory of Open Access Journals (Sweden)
Mechouma Rabiaa
2014-01-01
Full Text Available In recent years, power demand of industrial applications has increased significantly reaching some megawatts. The use of multilevel converters for applications of medium and high powers is proposed as a solution to drawback semiconductor technology. A multilevel converter not only achieves high power ratings, but also enables the use of renewable energy sources. Renewable energy sources such as photovoltaic can be easily interfaced to a multilevel converter system for a high power application. This paper presents the simulation study in Matlab/Simulink of a grid connected photovoltaic three phase Neutral Point Clamped (NPC inverter with DC/DC boost converter for constant and variable solar radiation.
Arshak, Khalil; Almukhtar, Basil
2000-01-01
peer-reviewed In this work a step by step planar transformer design proccdare for Flybock switch-mode DC-DC converter application is presented. This transformer has a maximum dimention of 2cm x 2cm x 0.4cm aiming to achieve an efficiency of 99% at an operating frequency of 500kHz. This planar transformer is designed specially for thick film technology development.
Development of TMS320F2810 DSP Based Bidirectional buck-boost Chopper
Mr. K.S. Chakradhar*1,; M.Ayesha siddiqa2; T.Vandhana3
2014-01-01
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 respon...
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.
电动汽车用数字型直流-直流转换器设计%Design of digital DC-DC converter for electric vehicles
Institute of Scientific and Technical Information of China (English)
滕聪; 黄金强; 禄盛; 黄智宇
2012-01-01
The electric vehicle may win an opportunity due to the pollution of traditional vehicles. The DC-DC converter is an important device for the popularity of electric vehicles, in order to absorb the advantages of digital converter and meet the requirement of wide-range input voltage, the concept of digital DC-DC converters for electric vehicle has been a research subject in EVs area. However, this method requires high dynamic response and wide-range input voltage. A two-stage DC-DC converter controlled by automotive MCU and software was presented, based on the simulation result of small-signal model. The component parameters and test results were described. The results show that the DC-DC converter controlled by digital chip is a real-time programmability, and can meet the requirements of electric vehicles.%随着传统汽车污染的不断增加,以电动汽车为代表的新能源汽车迎来了机遇.而直流-直流( DC-DC)转换器是电动汽车中不可缺少的一种装置.为了吸纳数字型转换器的优点,以及符合宽范围输入电压的要求,电动汽车中用数字型DC-DC转换器已经成为新能源汽车领域中一个热门研究.然而,这种方法需要快速的动态响应.因此,根据其小信号模型仿真结果设计了一个两级转换拓扑的DC-DC转换器,并且设计了基于汽车级数字芯片控制的硬件电路平台和软件算法程序,并给出了DC-DC转换器的元件参数及测试结果.结果表明由数字芯片控制的DC-DC转化器是实时可编程的,也满足汽车电子的要求.
采用LCD箝位电路的正激DC-DC变换器%A Forward DC-DC Converter with a LCD Clamp Circuit
Institute of Scientific and Technical Information of China (English)
王国礼; 金新民
2000-01-01
In this paper a forward DC-DC converter with a LCD clamp circuit is propsed. The core is reset through this simple clamp circuit, and the efficiency of the converter is improved due to avoiding the energy loss.%介绍了一种采用LCD箝位电路的正激DC-DC变换器，它以十分简单的电路结构实现了变压器铁心的磁通复位，并且避免了能量的损耗，提高了变换器的效率。
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.
A fully on-chip three-terminal switched-capacitor DC-DC converter for low-voltage CMOS LSIs
Kojima, Yuta; Hirose, Tetsuya; Tsubaki, Keishi; Ozaki, Toshihiro; Asano, Hiroki; Kuroki, Nobutaka; Numa, Masahiro
2016-04-01
In this paper, we present a fully on-chip switched-capacitor DC-DC converter for low-voltage CMOS LSIs. The converter has three terminals of input, ground, and output, by developing control circuits with fully on-chip configuration. We employ an ultra low-power nanoampere bias current and voltage reference circuit to achieve ultra low-power dissipation of control circuits. It enables us to realize a highly efficient power conversion circuit at light-load-current applications. The converter achieves highly efficient and robust voltage conversion using a pulse frequency modulation control circuit and a start-up/fail-safe circuit. Measurement results demonstrated that the converter can convert a 3.0 V input into 1.2 V output successfully. The start-up and fail-safe operations were confirmed through the measurement. The efficiency was more than 50% in the range of 2-6 µA load current.
Sample-Data Modeling of a Zero Voltage Transition DC-DC Converter for On-Board Battery Charger in EV
Teresa R. Granados-Luna; Ismael Araujo-Vargas; Francisco J. Perez-Pinal
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 ...
FRAPPE,E; DE-BERNARDINIS,A; Coquery, G.; Bethoux, O.; Marchand, C
2011-01-01
In transport application, long high power PEM fuel cell stacks could suffer from voltage discrepancy between cells due to severe constraints or appearance of localized faults in case of bad water management, moreover the output power of the stack is limited by the weakest group of cells. This article proposes a three-part segmented fuel cell associated with an isolated four-source DC/DC converter which makes possible a power sharing between the fuel cell segments according to their state-of-h...
DEFF Research Database (Denmark)
Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.
2013-01-01
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...... 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...
Feld, L.; Karpinski, W.; Klein, K.; Lipinski, M.; Preuten, M.; Rauch, M.; Schmitz, S.; Wlochal, M.
2016-02-01
The CMS collaboration has adopted a DC-DC conversion powering scheme for the Phase-1 Upgrade of its pixel detector. DC-DC buck converters with a conversion ratio of around 3 are installed on the support structures, outside of the sensitive tracking region, requiring a re-design of the low and high voltage distribution to the pixel modules. After several years of R&D, the project has entered the production phase. A total of 1800 DC-DC converters are being produced, and rigorous quality assurance and control is being employed during the production process. 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.
Research on a Novel Soft-Switching Buck Converter
Peng Ge; Ben Niu; Yuanbin Li
2013-01-01
Based on classical zero voltage transition buck pwm converter, an ideal buck converter with pwm-controlled soft-switching circuit is proposed. The proposed auxiliary circuit allows the main switch to operate with zero-voltage switching. Besides, all of the semiconductor devices operate under soft-switching conditions. Thus, losses were reduced. It was analyzed in detail to demonstrate the operating principle of the novel circuit. Finally, simulation results are given analysis and the simulati...
Institute of Scientific and Technical Information of China (English)
Ye Qiang; Liu Jie; Yuan Bing; Lai Xinquan; Liu Ning
2012-01-01
A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented.By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA),the proposed circuit generates two zeros to realize high closed-loop stability.Meanwhile,full on-chip integration is also achieved due to its simple structure.Hence,the number of off-chip components and the board space is greatly reduced.The structure of the dual signal path OTA is also optimized to help get a better transition response.Implemented in a 0.5 μm CMOS process,the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability.The test results show that both load and line regulations are less than 0.3％,and the output voltage can be recovered within 15 μs for a 400 mA load step.Moreover,the compensation components area is less than 2％ of the die's area and the board space is also reduced by 11％.The efficiency of the whole chip can be up to 95％.
International Nuclear Information System (INIS)
A novel on-chip frequency compensation circuit for a voltage-mode control DC/DC converter is presented. By employing an RC network in the two signal paths of an operational transconductance amplifier (OTA), the proposed circuit generates two zeros to realize high closed-loop stability. Meanwhile, full on-chip integration is also achieved due to its simple structure. Hence, the number of off-chip components and the board space is greatly reduced. The structure of the dual signal path OTA is also optimized to help get a better transition response. Implemented in a 0.5 μm CMOS process, the voltage mode control DC/DC converter with the proposed frequency compensation circuit exhibits good stability. The test results show that both load and line regulations are less than 0.3%, and the output voltage can be recovered within 15 μs for a 400 mA load step. Moreover, the compensation components area is less than 2% of the die's area and the board space is also reduced by 11%. The efficiency of the whole chip can be up to 95%. (semiconductor integrated circuits)
Sample-Data Modeling of a Zero Voltage Transition DC-DC Converter for On-Board Battery Charger in EV
Directory of Open Access Journals (Sweden)
Teresa R. Granados-Luna
2014-01-01
Full Text Available 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 battery charger. A piece-wise linear analysis of the converter is the basis of the technique presented such that a large-signal model and, therefore, a small-signal model of the converter are derived. Numerical and simulation results of a 250 W test rig validate the model.
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...
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
Institute of Scientific and Technical Information of China (English)
李峰; 魏廷存; 郑宇亮; 郑然
2012-01-01
在高精度数字DC-DC变换器设计中,必须建立变换器功率级的精确模型.通过分析现有功率级离散模型与连续模型的拟合度,建立了拟合程度更高的修正离散功率级模型.为简化数字控制器设计,针对修正离散功率级模型,提出了一种含单一设计参数的数字补偿器设计方法,并分析了该补偿器对系统稳态和瞬态性能的影响.基于Altera Cyclone Ⅲ FPGA开发板,实现了数字Buck变换器,测试结果表明:1.8V输出电压下,电压纹波率小于1％；0.4 A负载电流跳变时,过渡时间为0.22 ms,实验结果证明了修正离散功率级模型的精确性及数字补偿器的有效性.%For high precision design of digital DC-DC converters, it is necessary to establish the accurate discrete model of power stage. A modified discrete model of power stage with high degree of fitting with continuous model in magnitude and phase is built after analyzing the present discrete power stage model. Based on the modified power stage model, a digital compensator with one design parameter is proposed to simplify the design process, and also the steady-state and dynamic performances of converters using this compensator are analyzed. The digital Buck DC-DC converters is implemented on FPGA (Altera Cyclone III), and the experimental results indicate that the output ripple rate is less than 1% for 1.8 V output voltage, the transitional time is 0.22 ms for 0.4 A load step change, and prove the accuracy of modified discrete power stage model and the validity of the proposed digital compensator.This work is supported by National Natural Science Foundation of China (No. 60972157).
Demirbaş, Şevki; Fidanboy, Hikmet; Kurt, Erol
2016-08-01
In this paper, detailed analyses of the chaotic behavior observed in a buck-boost converter are presented. Although this basic converter system is already known world-wide for the purpose of dc-dc conversion of the output of renewable energy systems, it indicates certain chaotic regimes where both the output amplitude and frequency change randomly. This chaotic regime can yield an unstable output over the resistive or resistive/inductive electrical loads. This study presents a detailed map for the regular and chaotic regions in terms of material parameters, such as converter capacitance C, resistive load R, and inductive load L. Thus, the stable area of operation for efficient and renewable electricity production will be ascertained for the studied converter system. We emphasize that the material parameters C, R, and L play important roles in generating energy from the solar cell; indeed, the stability increases with higher values of the converter capacitor and load inductance, whereas it decreases according to the resistive load. A number of periodic windows have been observed and the output frequency gives a broad-band spectrum of up to 50 kHz.
Demirbaş, Şevki; Fidanboy, Hikmet; Kurt, Erol
2016-03-01
In this paper, detailed analyses of the chaotic behavior observed in a buck-boost converter are presented. Although this basic converter system is already known world-wide for the purpose of dc-dc conversion of the output of renewable energy systems, it indicates certain chaotic regimes where both the output amplitude and frequency change randomly. This chaotic regime can yield an unstable output over the resistive or resistive/inductive electrical loads. This study presents a detailed map for the regular and chaotic regions in terms of material parameters, such as converter capacitance C, resistive load R, and inductive load L. Thus, the stable area of operation for efficient and renewable electricity production will be ascertained for the studied converter system. We emphasize that the material parameters C, R, and L play important roles in generating energy from the solar cell; indeed, the stability increases with higher values of the converter capacitor and load inductance, whereas it decreases according to the resistive load. A number of periodic windows have been observed and the output frequency gives a broad-band spectrum of up to 50 kHz.
Directory of Open Access Journals (Sweden)
Kosenko Roman
2015-07-01
Full Text Available This paper compares semiconductor losses of the galvanically isolated quasi-Z-source converter and full-bridge boost DC-DC converter with active clamping circuit. Operation principle of both converters is described. Short design guidelines are provided as well. Results of steady state analysis are used to calculate semiconductor power losses for both converters. Analytical expressions are derived for all types of semiconductor power losses present in these converters. The theoretical results were verified by means of numerical simulation performed in the PSIM simulation software. Its add-on module “Thermal module” was used to estimate semiconductor power losses using the datasheet parameters of the selected semiconductor devices. Results of calculations and simulation study were obtained for four operating points with different input voltage and constant input current to compare performance of the converters in renewable applications, like photovoltaic, where input voltage and power can vary significantly. Power loss breakdown is detailed and its dependence on the converter output power is analyzed. Recommendations are given for the use of the converter topologies in applications with low input voltage and relatively high input current.
Analysis of a PWM Resonant Buck Chopper for Use as a Ship Service Converter Module
Ciezki, John G.; Ashton, Robert W.
1999-01-01
The Navy's interest in implementing a DC Zonal Electric Distribution System (DC ZEDS) in the next generation of surface combatant has motivated considerable research work into dc-dc converters. The switching frequency of a hard-switched dc-dc converter is limited by the maximum admissible switching losses allowed by the switch, heat sink, and cooling process. Also, hard- switched converters contribute significant Electromagnetic Interference (EMI) concerns for the system. This study provides ...
Wide input high step-up isolated DC/DC converter%宽输入高增益隔离升压型DC/DC变换器
Institute of Scientific and Technical Information of China (English)
肖文英; 戴日光
2012-01-01
隔离升压型DC/DC变换器是一类可以将低压直流母线变换成高压直流母线并实现电气隔离的变换器的统称.该技术在新能源发电领域如燃料电池发电系统以及微逆变器系统中应用广泛,其研究热点是宽输入适应性、高增益和高效率功率变换.LLC谐振变换器很好地符合这些要求.为此,研究了基于全桥LLC谐振变换器的高增益隔离升压型DC/DC变换器,提出了单级式和两级式两种方案,单级式方案为输出稳压LLC谐振变换器,而两级式方案为Boost变换器级联输出不稳压LLC谐振变换器.分别提出了LLC谐振变换器在单级式和两级式方案中的基于最佳励磁电感的谐振腔参数设计方法,并且分别通过样机实验验证了所提出的设计方法的有效性.%The isolated step-up DC/DC converter is a kind of converter that can convert low DC voltage bus into high DC voltage bus and realize electrical isolation. This technology has been widely used in new energy generation, such as fuel cell power system and micro-inverter system. Its research focuses on wide input adaptation, high step-up and high efficiency power conversion. LLC resonant converter perfectly satisfies these requirements. For this reason, high step-up DC/DC converter based on full bridge LLC resonant converter was studied in this paper. Two structures were presented, namely, single-stage structure applying regulated LLC resonant converter and two-stage structure applying Boost converter cascaded unregulated LLC resonant converter. The design method of the resonant tank under different structures based on the optimal magnetizing inductance was proposed. Finally, the prototypes of regulated and unregulated LLC resonant converter were built to verify the verification of the proposed method.
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...
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
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...... to verify the validity of the theoretical analysis and also demonstrate the converter’s performance over wide variations in input voltage....
Directory of Open Access Journals (Sweden)
R. Ramesh,
2014-03-01
Full Text Available Single phase ac-dc converters having high frequency isolation are implemented in buck, boost, buck-boost configuration with improving the power quality in terms of reducing the harmonics of input current. The paperpropose the circuit configuration, control mechanism, and simulation result for the single phase ac-dc converter.
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...
Accurate Modeling of Buck Converters with Magnetic-Core Inductors
DEFF Research Database (Denmark)
Astorino, Antonio; Antonini, Giulio; Swaminathan, Madhavan
2015-01-01
In this paper, a modeling approach for buck converters with magnetic-core inductors is presented. Due to the high nonlinearity of magnetic materials, the frequency domain analysis of such circuits is not suitable for an accurate description of their behaviour. Hence, in this work, a timedomain model...... of buck converters with magnetic-core inductors in a SimulinkR environment is proposed. As an example, the presented approach is used to simulate an eight-phase buck converter. The simulation results show that an unexpected system behaviour in terms of current ripple amplitude needs the inductor core...
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2013-01-01
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......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...... 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...
Soft-Switching Resonant Reset Dual Switch Forward DC/DC Converter%软开关谐振复位双管正激DC/DC变流器
Institute of Scientific and Technical Information of China (English)
洪小圆; 陈威; 吕征宇
2009-01-01
提出了一种新颖的双管正激DC/DC变流器,利用谐振复位使变流器工作在0.5以上的占空比,利用变压器二次侧串联饱和电感的方法使变流器所有开关管实现软开关,适于宽范围输入、高效率要求的应用场合.分析了变流器的工作原理,对变流器的特性进行了详细的分析.最后以一台250～400V直流输入,54V/5A输出的样机验证了该变流器的可行性.%This paper presents a new dual switch forward DC/DC converter topology. The duty cycle can be more than 0.5 by resonant reset. In addition, soft switching operation is achieved for all switches of the presented converter by adding a saturable reactor . It means that the converter is very attractive for wide range input and high efficiency application. In this paper, the operation principle and characteristic of this converter are analysed in details. Finally, the advantages mentioned above are verified by a 250~400V input, 54V/5A output prototype.
不对称控制全桥副边双谐振DC-DC变换器%Asymmetrical Full-bridge Secondary Dual Resonance DC-DC Converters
Institute of Scientific and Technical Information of China (English)
陈章勇; 肖皓中; 陈利; 许建平
2013-01-01
An asymmetrical full-bridge secondary dual resonance (FB-SDR) DC-DC converter is proposed. Without auxiliary circuits, the proposed converter can achieve zero voltage switching (ZVS) for the power switches and zero current switching (ZCS) for the rectifier diodes in the entire operating range. The switching losses and diode reverse-recovery losses are thus decreased. The circulating current loss is eliminated with the asymmetrical PWM strategy. Moreover, the proposed converter eliminates the voltage spike and oscillation of the rectifier diodes, clamps the diode voltage at the output voltage to decrease the voltage stress of the rectifier diodes. The analysis and design considerations of the converter are presented. Finally, experimental results from a 1 kW 400 V/48 V prototype were presented to verify the analysis of the proposed converter.%提出一种全桥副边双谐振(full-bridge secondary-dual-resonance，FB-SDR)DC-DC 变换器。变换器无需添加辅助电路即可在全负载范围内实现开关管的零电压开关和副边整流二极管的零电流关断，减小了开通损耗和反向恢复损耗；同时，采用不对称控制策略，消除了传统移相全桥变换器的环流损耗，提高了变换器的效率；有效抑制了整流二极管的电压尖峰和振荡，将整流二极管电压箝位在输出电压，减小了电压应力，进一步提高了变换器的性能。详细研究FB-SDR变换器的工作原理及稳态特性，并对电路关键参数进行设计。最后，通过搭建一台1 kW、400 V/48 V 的实验样机，验证理论分析的正确性。
Closed Loop Control of Soft Switched Interleaved Buck Converter
Directory of Open Access Journals (Sweden)
R. Shenbagalakshmi
2012-06-01
Full Text Available Design, Modeling and Simulation of a closed loop control is presented for Interleaved Buck Converter with Soft Switching. The features of the closed loop system are to reduce the switching losses and load current sharing among the parallel connected converters. The control system of the converter is designed using PWM technique. In order to improve the transient response and dynamic stability of the converters, the controller parameters are designed based on current mode control. Resonant components thus designed enable the application of zero current switching for both the converters connected in parallel thereby maintaining greater efficiency and minimizing voltage and current oscillations. The system analysis, design and performance are verified through simulation using MATLAB/Simulink environment. The simulation approach reveals the high speed dynamic performance of the closed loop system designed using robust PID controller. The laboratory prototype of the Buck converter is developed to verify the controller platform using PIC16F877A microcontroller.
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...
Directory of Open Access Journals (Sweden)
T.NageswaraRao
2012-07-01
Full Text Available A multiport converter promises cost-effective, flexible and more efficient energy processing by utilizing only a single power stage. Multiport converters, a promising concept for alternative energy systems, have attracted increasing research interest recently. Zero Voltage Switching (ZVS alleviates the switching losses and improves the converter overall efficiency. Zero voltage switching can be achieved with the help of coupled inductor which also regulates the input current during the load disturbances. To reduce the switching losses and henceforth to improve efficiency of converter system, Zero Voltage Switching (ZVS is employed. . This paper presents a two output ports single stage boost converter with ZVS. The proposed multi output port converter with soft switching is simple and efficient. The analysis is carried out for open loop and closed loop control. The simulation results for the same are presented in this paper.
Jaouen, Cédric; Multon, Bernard; Barruel, Franck
2011-01-01
This paper discusses a design methodology for power electronic converters according to the Global Energy Requirement (GER) criterion, i.e. the primary energy consumption over their entire life cycle. For given specifications of the converter, each power component of a self-oscillating flyback converter and the main control parameters are optimized using scaling laws for given technologies. Models linking sizes of components, loss parameters and embodied energy parameters are presented. Finall...
Thermal Modeling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Zygimantas; Zhang, Zhe; Pittini, Riccardo;
2014-01-01
Power electronic converters are widely used and play a pivotal role in electronics area . The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determine...
Thermal Modelling and Design of On-board DC-DC Power Converter using Finite Element Method
DEFF Research Database (Denmark)
Staliulionis, Z.; Zhang, Z.; Pittini, R.;
2014-01-01
Power electronic converters are widely used and play a pivotal role in electronics area. The temperature causes around 54 % of all power converters failures. Thermal loads are nowadays one of the bottlenecks in the power system design and the cooling efficiency of a system is primarily determined...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
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...
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...
DEFF Research Database (Denmark)
Mostaan, Ali; Alizadeh, Ebrahim; Soltani, Mohsen
2014-01-01
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...
Sliding mode control of reaction flywheel-based brushless DC motor with buck converter
Institute of Scientific and Technical Information of China (English)
Liu Gang; Zhang Cong
2013-01-01
Reaction flywheel is a significant actuator for satellites' attitude control.To improve out-put torque and rotational speed accuracy for reaction flywheel,this paper reviews the modeling and control approaches of DC-DC converters and presents an application of the variable structure system theory with associated sliding regimes.Firstly,the topology of reaction flywheel is constructed.The small signal linearization process for a buck converter is illustrated.Then,based on the state averaging models and reaching qualification expressed by the Lee derivative,the general results of the sliding mode control (SMC) are analyzed.The analytical equivalent control laws for reaction flywheel are deduced detailedly by selecting various sliding surfaces at electromotion,energy consumption braking,reverse connection braking stages.Finally,numerical and experimental examples are presented for illustrative purposes.The results demonstrate that favorable agreement is established between the simulations and experiments.The proposed control strategy achieves preferable rotational speed regulation,strong rejection of modest disturbances,and high-precision output torque and rotational speed tracking abilities.
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
. 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....
Morimoto, Keiki; Doi, Toshimitsu; Manabe, Haruhiko; Ahmed, Tarek; Hiraki, Eiji; Lee, Hyun-Woo; Nakaoka, Mutsuo
This paper presents a new circuit topology of full-bridge soft-switching PWM inverter linked DC-DC power converter composed of conventional full-bridge high frequency PWM inverter with high frequency transformer and an active quasi-resonant snubber consisting of an additional power switching device in series with DC busline and a lossless capacitor in parallel with DC busline. Under this proposed high frequency soft-switching PWM inverter linked DC-DC converter, four power switches in the full-bridge arms and DC busline series switch can achieve ZVS at turn-off commutation. By developing the advanced soft-switching PWM high frequency inverter type DC-DC converter, although the conduction power loss of DC busline series power switch increases a little, the total turn-off switching loss of full-bridge high frequency inverter power modules can be sufficiently lowered more and more in the higher frequency range of 60kHz. As a result, when the switching frequency of high frequency inverter power stage using IGBT power modules is designed so as to be more than about 10kHz, the more the switching frequency of inverter increases, the more this high frequency soft-switching DC-DC converter has remarkable advantage as for the power conversion efficiency as compared with the conventional hard-switching PWM inverter DC-DC converter. Its practical effectiveness of high power density and high performance is actually proved for TIG arc welding equipment in industry.
A bi-directional DC/DC converter for hybrid wind generator/battery system with state machine control
Energy Technology Data Exchange (ETDEWEB)
Hua, C.C.; Liao, Y.C. [National Yunlin Univ. of Science and Technology, Yunlin, Taiwan (China). Dept. of Electrical Engineering
2008-07-01
A bi-directional DC to DC converter used in a hybrid wind generator/lead-acid battery power system was presented. A state machine control strategy was used to control both the system power flow and load distribution. It was also used to increase the power capacity of the system. The battery was also charged or discharged through the bi-directional DC to DC converter. Multi-stage current charging control of the batteries was accomplished by adjusting the duty cycle of the power converter. This also improved the charging efficiency by the maximum power point tracking algorithm. It was concluded that the proposed control method can be readily extended to other renewable energy conversion systems. 6 refs., 13 figs.
Single-Event Transient Testing of the Crane Aerospace and Electronics SMHF2812D Dual DC-DC Converter
Casey, Megan
2015-01-01
The purpose of this testing was to characterize the Crane Aerospace & Electronics (Crane) Interpoint SMHF2812D for single-event transient (SET) susceptibility. These data shall be used for flight lot evaluation, as well as qualification by similarity of the SMHF family of converters, all of which use the same active components.
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.
Simpliﬁed loss analysis and comparison of full-bridge, full-range-ZVS DC-DC converters
Indian Academy of Sciences (India)
Shubhendu Bhardwaj; Mangesh Borage; Sunil Tiwari
2008-10-01
The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters. Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS DC–DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to be consistent with the experimental efﬁciency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently proposed new topology has the least penalty of additional losses.
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 μm) silicone elastomer film with a compliant metallic electrode layer on both sides. The DEAP is fundamentally a capacitor that is capable of very high strain. The property that the polymer changes its shape, as a result of...... topology to obtain high voltage at low current, for driving the DEAP actuator. Simulation and experimental results for uni-directional flyback converter topology are shown....... 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......The Dielectric Electro Active Polymer (DEAP) material is a very thin (~80 μm) silicone elastomer film with a compliant metallic electrode layer on both sides. The DEAP is fundamentally a capacitor that is capable of very high strain. The property that the polymer changes its shape, as a result of...
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
Accurate Sliding-Mode Control System Modeling for Buck Converters
DEFF Research Database (Denmark)
Høyerby, 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...... modeling the hysteretic comparator as an infinite gain. Correct prediction of output impedance is shown to be enabled by the use of a more elaborate, finite-gain model of the hysteretic comparator, which takes the effects of time delay and finite switching frequency into account. The demonstrated modeling...... approach also predicts the self-oscillating switching action of the sliding-mode control system correctly. Analytical findings are verified by simulation as well as experimentally in a 10-30V/3A buck converter....
Highly efficient PWM synchronous buck converter with optimized LDMOS
Roy, Swarnil; Mukherjee, Sagar; Sarkar, Chandan Kumar
2015-07-01
In this work, a design of high efficiency synchronous buck converter with an optimized LDMOS is presented which works in VHF frequency domain. The circuit performance of the buck converter is then analyzed and optimized to increase the efficiency and to reduce the power losses without modifying the circuit. The analysis and optimization is performed by varying the different device parameters like drift region doping concentration (DDrift) and drift region length (LDrift) along with the circuit level parameters like the dead time and the switching frequency. The effect of the parameters is found to reduce the power losses of the circuit. The circuit with optimized parameters yields 80% efficiency at 100 MHz switching frequency.
On-chip SIDO buck converter with independent outputs
Martínez García, Herminio; Silva-Martínez, José
2013-01-01
The portable electronics market is rapidly migrating towards more compact devices requiring multiple high-integrity high-efficiency voltage supplies for empowering the systems. This paper demonstrates a single inductor used in a buck converter with two output voltages from an input battery with voltage of value 3 V. The main targets are low cross regulation between the two outputs to supply independent load current levels while maintaining desired output voltage values well within the accepta...
A New Multi-channel DC/DC Converter with Two Inputs%一种新的双输入多通道直流变换器
Institute of Scientific and Technical Information of China (English)
黄志翔; 王维俊; 张欢
2013-01-01
Multiple unidirectional and bidirectional DC converters are usually needed in the traditional energy storage unit of the distributed generation system,to realize its function. The paper puts forward a new multi-channel DC converter with two inputs, whose function is equivalent to a DC converter plus a bidirectional DC converter. The working principle of the multi-channel DC converter with two inputs is analyzed,the steady state equation and the energy management method of converter are worked out. Sim-ulation experiment is conducted and the validity of the analysis is verified by using Saber software. It is concluded that the converter not only possesses the advantages of double input DC Buck converter,but makes it possible that renewable energy supply power to storage input source.%在传统的含储能单元分布式供电系统中，一般都需要多个单向直流变换器和双向直流变换器才能实现其功能。提出一种新的双输入多通道直流变换器，它的功能等效于一个单向直流变换器和一个双向直流变换器。分析了双输入多通道直流变换器的工作原理，给出了变换器的稳态关系式以及能量管理方法，并运用Saber软件进行仿真，验证了理论分析的正确性。该直流变换器除具有双输入Buck直流变换器的优点外，还能实现可再生能源向储电输入源充电。
Notch filter feedback controlled chaos in buck converter
Institute of Scientific and Technical Information of China (English)
Lu Wei-Guo; Zhou Luo-Wei; Luo Quan-Ming
2007-01-01
A method of controlling chaos in the voltage-mode buck converter is presented by using an improved notch filter feedback control in this paper. The proposed control part comprises a notch filter and a low-pass filter. The discrepancy between the outputs of the two filters is introduced into the control prototype of the power converter. In this way, the system period-1 solution is kept unchanged. The harmonic balance method is applied to analysing the variation law of the system bifurcation point, and then the stable range of the feedback gain is ascertained. The results of simulation and experiment are also given finally.
Modeling and Simulation of Buck-Boost Converter with Voltage Feedback Control
Zhou Xuelian; He Qiang
2015-01-01
In order to design the control system, it is necessary to have an exact model of buck-boost converter. This paper put forward the transfer function model of buck-boost converter by the state-space average method. The open-loop transfer function model of uncompensated system is deduced according to the mathematic model of the buck-boost converter, the controller is designed according to frequency domain. The phase and magnitude margin of the open-loop system of the buck-boost converter with co...
An FPGA Based Controller for a SOFC DC-DC Power System
Directory of Open Access Journals (Sweden)
Kanhu Charan Bhuyan
2013-01-01
Full Text Available Fuel cells are an attractive option for alternative power and of use in a variety of applications. This paper proposes a state space model for the solid oxide fuel cell (SOFC based power system that comprises fuel cell, DC-DC buck converter, and load. In this investigation we have taken up a case study for SOFC feeding a DC load where a DC-DC buck converter acts as the interface between the load and the source. A proportional-integral (PI controller is used in conjunction with pulse width modulation (PWM that computes the pulse width and switches the MOSFET at the right instant so that the desired voltage is obtained. The proposed model is validated through extensive simulation using MATLAB/SIMULINK. Controller for the fuel cell power system (FCPS is prototyped using XC3S500E development board containing a SPARTAN 3E Xilinx FPGA that simplifies the entire control circuit besides providing additional flexibility for further improvement. The results clearly indicate improved performance and validate our proposed model.
Dynamical analysis and experimental verification of valley current controlled buck converter
International Nuclear Information System (INIS)
The dynamical behaviours of valley current controlled buck converter are studied by establishing its corresponding discrete iterative map model in this paper. Time-domain waveforms and phase portraits of valley current controlled buck converter are obtained by Runge–Kutta algorithm through a piecewise smooth switching model. The research results indicate that the valley current controlled buck converter exhibits rich nonlinear phenomena, and it has routes to chaos through period-doubling bifurcation and border-collision bifurcation in a wide parameter range. Interesting inverse nonlinear behaviours compared with peak current controlled buck converter are observed in the valley current controlled buck converter. Analysis and simulation results are verified by experimental results. (general)
Robles Balestero, Juan Paulo; Lessa Tofoli, Fernando; Mendes de Seixas, Claudiner; Torrico Bascopé, Grover Victor; José Mendes de Seixas, Falcondes
2014-04-01
This article presents a comparative study involving a buck converter derived from the three-state switching cell in both operation modes, i.e. non-overlapping and overlapping modes, since it is well known in literature that several advantages can be addressed to topologies based on this approach. In the case of the mentioned converter, only part of the load delivered to the load flows through the controlled switches, so that operation at high-current high-power levels is possible. Besides, the design of reactive elements such as very autotransformer and filter inductor is performed for twice the switching frequency, with consequent reduction of size, weight and volume. Another clear advantage is that the area for which the converter operates in continuous conduction mode is wider than that for the discontinuous conduction mode in comparison with the so-called classical non-isolated buck converter. The operation of the converter, which was previously proposed in literature, is analysed considering the aforementioned modes in terms of the efficiency, and similar approaches for the non-isolated dc-dc conversion are also investigated.
M.K. Kazimierczuk; R.S. Geise; A. Reatti
1995-01-01
An extensive small-signal analysis of a single-loop voltage mode-control strategy for a pulse-width-modulated (PWM) boost DC-DC power converter operating in continuous conduction mode (CCM) is proposed using a new nonsymmetric phase controller. To model the boost power stage, a linear circuit model is used which includes all parasitic components such as the equivalent series resistance (ESR) of the filter capacitor, the ESR of the inductor, the transistor ON-resistance, and the diode forward ...
Institute of Scientific and Technical Information of China (English)
Yu Jiale; Lü Danzhu; Hong Zhiliang
2012-01-01
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 μm CMOS process.A small external inductor of 0.47 μH and a capacitor of 4.7 μF are used to lower the cost of the converter and keep the output ripple to less than 10 mV.The measurement results show that the overshoot of the load transient response is 8 mV @ 200 mA step and the dynamic voltage scaling (DVS) performance is a rise of 16 μs/V and a fall of 20μs/V.With a SAPTS technique and PFM control,the efficiency is maintained at more than 81% for a load range of 20 to 1 500 mA and the peak efficiency reaches 88.43%.
Institute of Scientific and Technical Information of China (English)
邱力军; 杨威; 王荣; 王伊笑
2015-01-01
In this paper the working principle of active clamp forward converter and the features of LM5026 chip were proposed. Furthermore, an example was proposed to discuss the design of transformer and inductor in active-clamp DC-DC converter. In the design example, efficiency of higher than 90%and the load regulation within 1%were obtained for an input of 28V and the implementation of the soft switch of the main MOSFET was realized, verifying the excellent load regulation and high efficiency of the active-clamp forward DC-DC converter.%介绍了有源钳位正激变换器的工作原理以及 LM5026芯片的功能特点，并以一个设计实例讨论了变压器和电感在有源钳位DC-DC变换器中的设计。结果表明，在28V 输入电压时，效率超过90%，负载调整率也在1%以内，且实现了主MOS管的软开通，验证了有源钳位正激变换器良好的负载调整率以及高效性。
Power decoupling method for single phase differential buck converter
DEFF Research Database (Denmark)
Yao, Wenli; Tang, Yi; Zhang, Xiaobin; Wang, Xiongfei; Loh, Poh Chiang; Blaabjerg, Frede
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...
Extended time-delay autosynchronization for the buck converter
Batlle, C; Olivar, G
1996-01-01
Time-delay autosynchronization (TDAS) can be used to stabilize unstable periodic orbits in dynamical systems. The technique involves continuous feedback of signals delayed by the orbit's period. One variant, ETDAS, uses information further in the past. In both cases, the feedback signal vanishes on the target periodic orbit and hence the stabilized periodic orbit is one of the original dynamical system. Furthermore, this control method only requires the knowledge of the period of the unstable orbit. The amount of feedback gain needed to achieve stabilization varies with the bifurcation parameter(s) of the system, resulting in a domain of control. In this paper we compute the domain of control of the unstable periodic orbits of the \\textit{buck} converter. We obtain a closed analytical expression for the curve $g:S^1 \\rightarrow\\C$ whose index determines the stability, and this index is then numerically computed. We run several simulations of the controlled system and discuss the results.
Capacitorless DC-DC regulator as a candidate topology for photovoltaic solar facilities
Martínez García, Herminio
2015-01-01
Linear-assisted DC/DC converters (or linearswitching hybrid DC/DC converters) consist of a voltage linear regulator (classic NPN or nMOS topologies and LDO) connected in parallel with a switching DC/DC converter. They are a good candidate for energy processing in photovoltaic solar facilities. In order to control these hybrid structures, different strategies exist, allowing fixing the switching frequency as a function of some parameters of the linear regulator. This article compares two contr...
Comparative Study of 4-Switch Buck-Boost Controller and Regular Buck-Boost
Directory of Open Access Journals (Sweden)
Taufik Taufik
2011-01-01
Full Text Available A very important characteristic that dc-dc converters require is the ability to efficiently regulate an output voltage with a wide ranging value of input voltages. A recently developed solution to this requirement is a synchronous 4-Switch Buck-Boost controller developed by Linear Technology. The Linear Technology’s LTC3780 controller chip enables the adoption of a 4-Switch switching topology as opposed to the traditional single-switch Buck-Boost topology. In this paper, the LTC3780’s 4-Switch BuckBoost topology is analyzed and its performance is compared against those of the regular single-switch Buck-Boost topology. Results from computer simulations demonstrate the benefits of using the 4-switch approach than the conventional buck-boost method.
DEFF Research Database (Denmark)
Zhang, Zhe; Thomsen, Ole Cornelius; Andersen, Michael A. E.
2013-01-01
This paper introduces a new zero-voltage-switching (ZVS) isolated DC-DC converter with two input ports which can be utilized in hybrid energy systems, for instance, in a fuel cell and super-capacitor system. By fully using two high frequency transformers, the proposed converter can effectively...... 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...
A Novel Soft-Switching Synchronous Buck Converter for Portable Applications
Mohapatra, K. K.; Swapnajit Pattnaik; Anup Kumar Panda
2008-01-01
This paper proposes a zero-voltage-transition (ZVT) pulse-width-modulated (PWM) synchronous buck converter, which is designed to operate at low voltage and high efficiency typically required for portable systems. A new passive auxiliary circuit that allows the main switch to operate with zero-voltage switching has been incorporated in the conventional PWM synchronous buck converter. The operation principles and a detailed steady-state analysis of the ZVT-PWM synchronous converter implemented ...
DEFF Research Database (Denmark)
Thummala, Prasanth; Zhang, Zhe; Andersen, Michael A. E.;
2014-01-01
the valley switchingtechnique during both charge and discharge processes, withoutthe need to sense signals on the output high-voltage side.Experimental results verifying the bidirectional operation of asingle high voltage flyback converter are presented, using afilm capacitor as the load. Energy......This paper presents a digital control technique toachieve valley switching in a bidirectional flyback converterused to drive a dielectric electro active polymer basedincremental actuator. The incremental actuator consists ofthree electrically isolated, mechanically connected capacitiveactuators....... The incremental actuator requires three highvoltage (~2.5 kV) bidirectional DC-DC converters, toaccomplish the incremental motion by charging anddischarging the capacitive actuators. The bidirectional flybackconverter employs a digital controller to improve efficiencyand charge/discharge speed using...
Modeling and Simulation of Buck-Boost Converter with Voltage Feedback Control
Directory of Open Access Journals (Sweden)
Zhou Xuelian
2015-01-01
Full Text Available In order to design the control system, it is necessary to have an exact model of buck-boost converter. This paper put forward the transfer function model of buck-boost converter by the state-space average method. The open-loop transfer function model of uncompensated system is deduced according to the mathematic model of the buck-boost converter, the controller is designed according to frequency domain. The phase and magnitude margin of the open-loop system of the buck-boost converter with compensator have both been increased. After compensating, this control system has the advantages of small overshoot and short settling time. It can also improve control system’s real time property and anti-interference ability.
Buck Converter with Soft-Switching Cells for PV Panel Applications
Directory of Open Access Journals (Sweden)
Cheng-Tao Tsai
2016-03-01
Full Text Available In power conversion of photovoltaic (PV energy, a hard-switching buck converter always generates some disadvantages. For example, serious electromagnetic interference (EMI, high switching losses, and stresses on an active switch (metal-oxide-semiconductor-field-effect-transistor, MOSFET, and high reverse-recovery losses of a freewheeling diode result in low conversion efficiency. To release these disadvantages, a buck converter with soft-switching cells for PV panel applications is proposed. To create zero-voltage-switching (ZVS features of the active switches, a simple active soft-switching cell with an inductor, a capacitor, and a MOSFET is incorporated into the proposed buck converter. Therefore, the switching losses and stresses of the active switches and EMI can be reduced significantly. To reduce reverse-recovery losses of a freewheeling diode, a simple passive soft-switching cell with a capacitor and two diodes is implemented. To verify the performance and the feasibility of the proposed buck converter with soft-switching cells for PV panel applications, a prototype soft-switching buck converter is built and implemented by using a maximum-power-point-tracking (MPPT method. Simulated and experimental results are presented from a 100 W soft-switching buck converter for PV panel applications.
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.
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.
基于DPA426R的开关电源环路补偿设计%Loop compensation design of DC/DC converter based on DPA426R
Institute of Scientific and Technical Information of China (English)
王斌
2012-01-01
针对基于集成电源管理芯片DPA426R的正激DC/DC变换器,研究了反馈控制环路的补偿设计方法.建立了开关电源闭环系统的s域传递函数模型,通过调整误差放大电路、光耦反馈电路、DPA426R控制电路等各个环节的电路参数来实现系统零极点的配置.反馈补偿设计无需改变系统的硬件电路结构,在配置零极点时有很大的灵活性,可以获得充足的环路设计裕量.应用Matlab仿真软件结合具体电路参数进行了系统的频域响应分析,仿真实验结果验证了反馈环路补偿设计的有效性.%A high frequency DC/DC converter was designed utilizing the integrated power management IC DPA426R. An approach to feedback control loop compensation was presented. The small signal model of the closed-loop control system for the DC/DC switching power supply in s-domain was built. The circuit parameters of the error amplifier, optocoupler and DPA426 were regulated, in order to realize the pole-zero configurations of the com pensation networks. The loop compensation was designed without changing the hardware circuit structure. The sufficient margin was achieved in the design of the feedback loop. A bode plot of the overall system was generated. The simulation results are shown to verify the validity of the loop compensation approach.
Institute of Scientific and Technical Information of China (English)
郭明明; 沈锦飞
2011-01-01
The switching loss,voltage and current stress of switching device is large and other shortcomings resulting in decrease efficiency of the system,when the traditional photovoltaic DC/DC converters operate in hard switching state.A soft switch Boost converter with simple structure, easy control is proposed which can greatly reduce switching losses and pressure drop of switching device.Finally, simulation and experimental results verify the converter main and auxiliary switch and freewheeling diode can achieve soft switching, thus transmission efficiency of photovoltaic power generation is improved.%针对传统光伏发电DC/DC变换器工作在硬开关状态时,因开关损耗大、开关管所承受的电压电流大等缺点导致的系统效率下降问题,采用了一种软开关Boost变换器,其结构简单,易于控制,大大减少了变换器工作中的开关损耗,并且降低了开关管所承受的压降.最后通过仿真和实验证明变换器的主、辅开关管和续流二极管均能实现软开关,从而提高了光伏发电传输效率.
Institute of Scientific and Technical Information of China (English)
郑宇亮; 魏廷存; 李峰
2012-01-01
提出了一种应用于数字DC-DC变换器的高精度定点数字控制器的设计方法；在数字控制器的控制率运算中,将浮点数格式的控制参数转化为定点数格式,从而达到简化硬件电路的目的;该设计方法应用于降压型数字DC-DC变换器的设计中,并完成了基于FPGA的测试和验证；在500kHz的开关频率下,输出电压纹波为14mY,对于士0.5A的负载电流跳变,控制器响应时间约为330μs.测试结果表明,该设计方法在保持控制精度的前提下,可简化硬件电路的设计复杂度,并改善系统的瞬态性能.%A design method of high precision fixed-point digital controller, which is applied to digital DC-DC converter, is proposed. In order to simplify the complexity of hardware circuit, the control parameters of floating-point format are converted into fixed-point format during the operation of the digital controller. The design method is applied to digital DC-DC converter, and the testing and verification based on FPGA are accomplished. When switching frequency is 500KHz, output voltage ripple is 14mV, and when load current varies ± 0. 5A, response time of the controller is about 330μs. The test results indicate that this design method not only preserves the control precision but also simplifies the complexity of hardware circuit as well as improves the system transient performances.
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 can’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.
Analysis of Discharge Spark Energy in Buck Converter of a Continuous Mode of Inductive Current
Institute of Scientific and Technical Information of China (English)
CUI Bao-chun; CHENG Hong; WANG Cong; LU Huan-yu; SHI Yun
2006-01-01
The basic idea of intrinsically safe circuit and the discharge spark in the Buck converter in the explosive atmospheres were introduced. The Buck converter is the main topological structure of the switch type of intrinsically safe circuit, which has two working modes: continuous inductive current (CCM - continuous conduction mode) and discrete inductance current (DCM - discontinuous conduction mode). The operating state of the continuous inductive current mode is analyzed in detail and the energy of discharge spark in various operating modes is discussed. The total energy will decrease with the increase of switch frequency, in a switching cycle; the discharge spark energy has a maximum and a minimum value. Therefore, the Buck converter has smaller discharge spark energy than the linear power circuit and the switch type of intrinsically safe circuit can enhance the output power and the conversion efficiency of the intrinsically safe power.
高输入输出变比的两级式DC/DC变换器%Two-stage DC/DC converter for high voltage input low voltage output case
Institute of Scientific and Technical Information of China (English)
张玄; 宁国云; 毛康宇; 黄声华
2011-01-01
Two-stage converter is more applicable than the single-stage converter for high voltage input low voltage output case. A Buck + LLC resonance full bridge topology was introduced in this paper. The operation principles and the characteristics of the LLC resonance full bridge topology were introduced. Then based on stability analysis of the two-stage converters high efficiency was achieved via rationally choosing the output voltage of front stage Buck circuit, the transformer turn ratio and resonance elements values of the end stage LLC resonance full bridge circuit. Finally, a 1 kW converter was designed, which had 210-270 V input and 27 V output. Then the experiment result was given.%两级式变换器比单级式变换器更适合应用在输入输出变比较高的DC/DC变换场合.研究了一种Buck+LLC谐振全桥的电路拓扑,阐述了LLC谐振全桥的原理和特性,在分析了这种两级变换器的稳定性基础上,通过合理选取前级Buck电路的输出电压、后级LLC谐振全桥变压器变比和谐振元件参数,提高了两级变换的效率.基于上述分析,采用该拓扑结构试制了一台功率1kW,210-270 V输入,27V输出的原理样机,并给出了实验结果.
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...
Design and implementation of an observer controller for a buck converter
LAKSHMI, Shenbaga; RAJA, T. Sree Renga
2014-01-01
An observer controller for a buck converter is presented. A state feedback gain matrix is derived in order to achieve the stability of the converter and to ensure the robustness of the controller. A load estimator is designed to estimate the unmeasurable variables and to obtain the zero output voltage error. A pulse-width modulation scheme is adopted to obtain the output voltage regulation. In order to improve the transitory response and dynamic constancy of the converter, the controlle...
Institute of Scientific and Technical Information of China (English)
谷雨; 张东来; 朱洪雨; 李悦
2011-01-01
Due to the intensity change of the output voltage on the solar array bus,Boost based bidirectional DC/DC converter is presented for the sake of providing continual and steady output voltage to the load in the entire orbit cycle. Simplicity, high stability and high efficiency are the advantages of this topology, meanwhile, minimum phase system could be achieved by inserting damping network.Conductance control is adopted to achieve better output response, moreover, voltage feedforward ensure the bandwidth of the conductance control invariable.Finally, the bidirectional experimental results under 1.5 kW are presented to verify the performance of the proposed converter and the efficiency of the converter is tested.%由于空间中太阳电池阵输出母线电压变化幅度较大,为保证电源在整个轨道周期内向负载提供持续稳定的电压,提出一种基于Boost拓扑结构的双向DC/DC变换器.该变换器拓扑简单,可靠性高,在大幅减小系统体积与成本的同时提高了系统的效率,并通过引入衰减网络优化Boost变换器为最小相位系统.变换器采用电导控制,并引入电压前馈控制以维持电导控制带宽的恒定.最后通过实验验证了变换器在1.5 kW功率下能量双向流动的工作特性,测试了变换器的效率.
Institute of Scientific and Technical Information of China (English)
Wang Fa-Qiang; Ma Xi-Kui
2013-01-01
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.
1 GHz GaAs Buck Converter for High Power Amplifier Modulation Applications
Busking, E.B.; Hek, A.P. de; Vliet, F.E. van
2012-01-01
A fully integrated 1 GHz buck converter output stage, including on-chip inductor and DC output filtering has been realized, in a standard high-voltage breakdown GaAs MMIC technology. This is a significant step forward in designing highspeed power control of supply-modulated HPAs (high power amplifie
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
Research and comparison of novel digital control for DC-DC converter%DC-DC变换器新型数字控制方式的研究与对比
Institute of Scientific and Technical Information of China (English)
关静
2013-01-01
提出了一种DC-DC变换器的新型数字控制电路,由频域上的移动平均电路、时域上的微分电路、抗混叠滤波器、A/D变换器、加法器、减法器等构成,并将该数字控制方式与通过DSP构成的最小相位FIR滤波器控制方式及IIR滤波器控制方式相对比,研究不同数字控制方式的过渡特性,仿真出各种控制方式的过冲电压和调整时间,结果表明所提的新型数字控制电路能够获得比最小相位FIR滤波器优越的控制特性,且由简单数字电路构成,成本较低,有利于实用.%This paper proposes a new method for the digitally controlled DC-DC converter. It consists of moving average circuit in the frequency-domain, the differential circuit in the time domain, anti-aliasing filter, A/D converter, adder, subtractor, etc. It studies the transition characteristics of different digital control processes, by comparing this digital circuit control process with the control processes of minimum phase FIR filter and IIR filter based on DSP. The voltage overshoot and adjustment time of the control processes is simulated. The results showed that the novel digital control method can gain better control characteristics than the control method of minimum phase FIR filter. Moreover, it consists of a simple digital circuit and costs little,and is easy to be put into practice.
Buck-Boost/Forward Hybrid Converter for PV Energy Conversion Applications
Sheng-Yu Tseng; Chien-Chih Chen; Hung-Yuan Wang
2014-01-01
This paper presents a charger and LED lighting (discharger) hybrid system with a PV array as its power source for electronic sign indicator applications. The charger adopts buck-boost converter which is operated in constant current mode to charge lead-acid battery and with the perturb and observe method to extract maximum power of PV arrays. Their control algorithms are implemented by microcontroller. Moreover, forward converter with active clamp circuit is operated in voltage regulation cond...
Adaptive prediction in digitally controlled buck converter with fast load transient response
Lee, TLA; Chan, PCH
2012-01-01
An adaptive prediction scheme based on linear extrapolation for digitally controlled voltage-mode buck-type switching converter is presented. A major drawback of conventional digitally controlled switching converters is bandwidth limitation due to the additional phase lag in the digital feedback control loop. By predicting the future error voltage, the ADC sampling time delay is compensated in order to achieve a higher bandwidth even with a modest sampling rate. Both simulation and measuremen...
Lee, ATL; Sin, JKO; Chan, PCH
2014-01-01
Digitally controlled switching converter suffers from bandwidth limitation because of the additional phase delay in the digital feedback control loop. In order to overcome the bandwidth limitation without using a high sampling rate, this paper presents an adaptive third-order digital controller for regulating a voltage-mode buck converter with a modest 2x oversampling ratio. The phase lag due to the ADC conversion time delay is virtually compensated by providing an early estimation of the err...
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.
A Novel Soft-Switching Synchronous Buck Converter for Portable Applications
Directory of Open Access Journals (Sweden)
Anup Kumar Panda
2008-01-01
Full Text Available This paper proposes a zero-voltage-transition (ZVT pulse-width-modulated (PWM synchronous buck converter, which is designed to operate at low voltage and high efficiency typically required for portable systems. A new passive auxiliary circuit that allows the main switch to operate with zero-voltage switching has been incorporated in the conventional PWM synchronous buck converter. The operation principles and a detailed steady-state analysis of the ZVT-PWM synchronous converter implemented with the auxiliary circuit are presented. Besides, the main switch and all of the semiconductor devices operate under soft-switching conditions. Thus, the auxiliary circuit provides a larger overall efficiency. The feasibility of the auxiliary circuit is confirmed by simulation and experimental results.
大功率高压输入的IGBT高频直-直变换器%A High-Power DC-DC Converter for High Frequency High-Input Voltage Using IGBT
Institute of Scientific and Technical Information of China (English)
彭光凤; 郝荣泰
1998-01-01
For the high frequency and high-input-voltage (sometimes reaching several kilo-volts) converter, its switching devices - IGBTs′ voltage rating can not suit this requirement. In this paper, a new cascaded-inverter-units structure is proposed, in which the high-input-voltage is divided into several parts and each part corresponds to one DC-AC converter. So the IGBT′s operating voltages are equal to the voltage of each divided part. In order to increase the output power, the output-rectifier-diodes usually are used in parallel, a method to balance the current by changing the linking type between the transformer secondary windings and the output-rectifier diodes is recommended. This method fully utilizes the transformer leakage inductance to realize the current-sharing function. In this paper, operation of a high-input voltage, high-power DC-DC converter is described. Both experimental and simulation results are shown for a small-full-scale-model converter.%在高频高压输入的情况下,开关器件绝缘门极双极晶体管(IGBT)的耐压不能满足要求.文中论述了一种逆变单元串联的结构,它将输入的高电压分成几部分,每一部分有一个DC-AC逆变器.此时,IGBT的工作电压等于各部分电压.为了提高输出功率,输出整流二极管通常并联连接,变压器的副边漏电感作为二极管的均流电感.并分析了高压输入的大功率DC-DC逆变器的工作情况,同时给出了模拟结果和实验结果.
Martínez García, Herminio; Grau Saldes, Antoni
2015-01-01
Hybrid DC-DC regulators or linear–assisted DC-DC regulators are structures that combine both a linear voltage regulator and a switching DC-DC converter. The main objective of this hybrid topology is to converge, in a single circuit topology, the best of both alternatives: One the one hand, obtaining small voltage output ripple, which is typical of linear regulator structures, and, on the other, achieving good energy efficiency, as in switching alternatives. While the linear regulator fixes th...
Advanced buck converter power supply ABCPS for APT
Energy Technology Data Exchange (ETDEWEB)
Street, R.; Overett, T.; Bowles, E. [General Atomics, San Diego, CA (United States)
1998-12-31
The United States Department of Energy (DOE) is planning to fabricate an Accelerator for the Production of Tritium (APT) at their Savannah River Site, to provide Tritium for national defense. The 1700 million electron volt (MeV) proton beam accelerator will be powered by radio frequency (RF) klystrons. A direct current (DC) power supply is required for each of the approximately two hundred and fifty 1-megawatt (MW) continuous wave klystrons in the RF power system. The requirements are that the power supply meet output performance specifications, provide fault protection for the klystron, have high efficiency, high reliability, good maintainability, and be readily manufacturable. As the power supplies are one of the largest cost elements in the accelerator, a technology review was made to determine the most economical approach to satisfy the requirements. A switch-mode power supply employing a buck-regulator was identified as being potentially the lowest cost approach. As the switch represents a certain development risk, a small-scale prototype has been constructed for evaluation, and has resulted in the decision to fabricate a full-scale prototype power supply. A description of the hardware will be presented.
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 it’s associated Drive System in simple and lucid manner. In this paper the drive system is proposed with a buck converter topology. It has the advantages of reduced switching losses, low inductor power loss, reduced ripple by using a pi-filter, which in turn makes the DC link voltage to be stable. The modeling and simulation of the PMBLDC motor is done using the software package MATLAB/SIMULINK. The operation principle of the buck converter is analyzed and the simulation results are presented in this paper to verify the theoretical analysis.
Smooth Starter for a DC Machine through a DC-to-DC Buck Converter
Linares-Flores J.; Antonio-García A.; Orantes-Molina A.
2011-01-01
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 s...
1 GHz GaAs Buck Converter for High Power Amplifier Modulation Applications
Busking, E.B.; Hek, A.P. de; Vliet, F.E. van
2012-01-01
A fully integrated 1 GHz buck converter output stage, including on-chip inductor and DC output filtering has been realized, in a standard high-voltage breakdown GaAs MMIC technology. This is a significant step forward in designing highspeed power control of supply-modulated HPAs (high power amplifiers). Agile power controlled HPAs are intended to find application in high-efficiency transmitters for both radio communication and radar applications, especially in which phased array transmit chai...
Optimization of Power MOSFET for High-Frequency Synchronous Buck Converter
Bai, Yuming
2003-01-01
Evolutions in microprocessor technology require the use of a high-frequency synchronous buck converter (SBC) in order to achieve low cost, low profile, fast transient response and high power density. However, high frequency also causes more power loss on MOSFETs. Optimization of the MOSFETs plays an important role in the system performance. Circuit and device modeling is important in understanding the relationship between the device parameters and the power loss. The gate-to-drain charge ...
Yigeng Huangfu; Ruiqing Ma; Abdellatif Miraoui
2012-01-01
This paper mainly discussed a method of high-frequency second-order sliding mode control for Buck converter in wind power systems. Because the wind energy of nature is always unpredictable and intermittent, the robust control such as sliding mode control is adopted in past literatures. In order to remove the high frequency chattering problem when the traditional sliding mode achieves convergence, the second order sliding mode algorithm is reviewed firstly. Meanwhile, the Buck converter taken ...
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.
A novel buck/LDO dual-mode DC—DC converter for efficiency improvement
International Nuclear Information System (INIS)
A novel buck/LDO dual-mode (BLDM) converter using a multiplexing power MOS transistor is proposed, which adaptively switches between buck mode and LDO mode to improve conversion efficiency. The chip was fabricated in a standard 0.35 μm CMOS process. Measurement results show that the peak efficiency is 97%. For the light load operation, the efficiency is improved by 14%. The efficiency keeps higher than 82.5% for the load current of 50 mA without any complex control or extra EMI due to the normal method of pulse frequency modulation (PFM) control used for improving the light load efficiency. It does not cost much extra chip area because no additional regulator PMOS is needed. It is more suitable for noise-restricted systems and battery-powered electronic devices for when battery voltage drops because of long hours of work. (semiconductor integrated circuits)
一种新型软开关 BUCK变换器%A NoveI Soft-switching BUCK Converter
Institute of Scientific and Technical Information of China (English)
刘吉星; 沈锦飞
2014-01-01
磁耦合谐振式无线电能传输采用直流斩波调压控制传输功率，传统的直流斩波电路开关损耗大，因此提出了一种新型的软开关BUCK变换器的改进电路，在电路中添加耦合电感、辅助电感和二极管，可以实现零电流开通和零电压关断。变换器结构简单，便于控制。介绍了电路工作原理和过程，设计了电路参数，进行了仿真和实验研究，最后给出了仿真和实验波形。%The magnetically coupled resonant wireless power transmission adopts DC chopper control over transmission power,while traditional DC chopper circuit switching has a high loss.This paper presents an improved circuit for a novel soft-switching BUCK DC-DC converter,where a coupled inductor,auxiliary inductor and diode are added to realize zero current switching-on and zero voltage switching-off.The converter has a simple structure and is easy to control.Furthermore,the paper describes the working principle and process of the circuit,designs circuit parameters,completes simulation and experimental research,and finally gives simulation and test waveforms.
A NoveI Soft-switching BUCK Converter%一种新型软开关 BUCK变换器
Institute of Scientific and Technical Information of China (English)
刘吉星; 沈锦飞
2014-01-01
磁耦合谐振式无线电能传输采用直流斩波调压控制传输功率，传统的直流斩波电路开关损耗大，因此提出了一种新型的软开关BUCK变换器的改进电路，在电路中添加耦合电感、辅助电感和二极管，可以实现零电流开通和零电压关断。变换器结构简单，便于控制。介绍了电路工作原理和过程，设计了电路参数，进行了仿真和实验研究，最后给出了仿真和实验波形。%The magnetically coupled resonant wireless power transmission adopts DC chopper control over transmission power,while traditional DC chopper circuit switching has a high loss.This paper presents an improved circuit for a novel soft-switching BUCK DC-DC converter,where a coupled inductor,auxiliary inductor and diode are added to realize zero current switching-on and zero voltage switching-off.The converter has a simple structure and is easy to control.Furthermore,the paper describes the working principle and process of the circuit,designs circuit parameters,completes simulation and experimental research,and finally gives simulation and test waveforms.
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).
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.
Birchenough, Arthur G.
2003-01-01
Improvements in the efficiency and size of DC-DC converters have resulted from advances in components, primarily semiconductors, and improved topologies. One topology, which has shown very high potential in limited applications, is the Series Connected Boost Unit (SCBU), wherein a small DC-DC converter output is connected in series with the input bus to provide an output voltage equal to or greater than the input voltage. Since the DC-DC converter switches only a fraction of the power throughput, the overall system efficiency is very high. But this technique is limited to applications where the output is always greater than the input. The Series Connected Buck Boost Regulator (SCBBR) concept extends partial power processing technique used in the SCBU to operation when the desired output voltage is higher or lower than the input voltage, and the implementation described can even operate as a conventional buck converter to operate at very low output to input voltage ratios. This paper describes the operation and performance of an SCBBR configured as a bus voltage regulator providing 50 percent voltage regulation range, bus switching, and overload limiting, operating above 98 percent efficiency. The technique does not provide input-output isolation.
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
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.
A novel single phase buck PFC converter in discontinuous capacitor voltage mode operation
Institute of Scientific and Technical Information of China (English)
邓超平; 凌志斌; 叶芃生
2003-01-01
A novel single-phase Buck converter for power factor correction is proposed. It features simple control due to the constant duty ratio PWM used. It can obtain unity power factor by selecting a suitable LC filter at its input to force the voltage of capacitor to operate in discontinuous capacitor voltage mode. And by using another resonant LC filter at its output, it can not only eliminate the input current distortion at the vicinity of the zero crossing of the supply but also drastically reduce the 100 Hz output voltage ripple. The validity of analysis is confirmed by simulation results and experimental results.
Sensorless Load Torque Estimation and Passivity Based Control of Buck Converter Fed DC Motor
Directory of Open Access Journals (Sweden)
S. Ganesh Kumar
2015-01-01
Full Text Available 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.
Directory of Open Access Journals (Sweden)
Yali Xiong
2008-01-01
Full Text Available This paper investigates the performance perspectives and theoretical limitations of trench power MOSFETs in synchronous rectifier buck converters operating in the MHz frequency range. Several trench MOSFET technologies are studied using a mixed-mode device/circuit modeling approach. Individual power loss contributions from the control and synchronous MOSFETs, and their dependence on switching frequency between 500 kHz and 5 MHz are discussed in detail. It is observed that the conduction loss contribution decreases from 40% to 4% while the switching loss contribution increases from 60% to 96% as the switching frequency increases from 500 KHz to 5 MHz. Beyond 1 MHz frequency there is no obvious benefit to increase the die size of either SyncFET or CtrlFET. The RDS(ON×QG figure of merit (FOM still correlates well to the overall converter efficiency in the MHz frequency range. The efficiency of the hard switching buck topology is limited to 80% at 2 MHz and 65% at 5 MHz even with the most advanced trench MOSFET technologies.
Institute of Scientific and Technical Information of China (English)
侯鑫尧; 倪强
2011-01-01
Base on analyzing the principle and working process of pulse-train（PT） control technique,a simple and practical PT controller is designed.PSpice Simulation results of PT controlled buck converter in discontinuous conduction mode（DCM） are performed in this%在分析开关电源脉冲序列（Pulse Train,PT）控制方法的原理和工作过程的基础上,设计了一种简单实用的脉冲序列控制电路。利用PSpice对PT控制DCM Buck变换器进行了仿真研究,并通过实验验证了脉冲序列控制器的可行性和正确性,为PT控制开关电源提供了一种有效的实施方案。
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 μm 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)
A 10 MHz ripple-based on-time controlled buck converter with dual ripple compensation
Institute of Scientific and Technical Information of China (English)
Lü Danzhu; Yu Jiale; Hong Zhiliang
2013-01-01
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 μm 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％.
A Novel Application of Zero-Current-Switching Quasiresonant Buck Converter for Battery Chargers
Directory of Open Access Journals (Sweden)
Kuo-Kuang Chen
2011-01-01
Full Text Available The main purpose of this paper is to develop a novel application of a resonant switch converter for battery chargers. A zero-current-switching (ZCS converter with a quasiresonant converter (QRC was used as the main structure. The proposed ZCS dc–dc battery charger has a straightforward structure, low cost, easy control, and high efficiency. The operating principles and design procedure of the proposed charger 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. Experiments were conducted using lead-acid batteries. The optimal parameters of the resonance components were determined using the load characteristic curve diagrams. These values enable the battery charger to turn on and off at zero current, resulting in a reduction of switching losses. The results of the experiments show that when compared with the traditional pulse-width-modulation (PWM converter for a battery charger, the buck converter with a zero- current-switching quasiresonant converter can lower the temperature of the activepower switch.
Push-Pull Converter Fed Three-Phase Inverter for Residential and Motor Load
Directory of Open Access Journals (Sweden)
Samuel Rajesh Babu
2015-06-01
Full Text Available The proposed paper is an new approach for power conditioning of a PV (photo-voltaic cell array. The main objective is to investigate an approach to provide and improve the delivered electric energy by means of power conditioning structures with the use of alternative renewable resources (ARRs for remote rural residential or industrial non-linear loads. This approach employs a series-combined connected boost and buck boost DC-DC converter for power conditioning of the dc voltage provided by a photo-voltaic array. The input voltage to the combined converters is 100 V provided from two series connected PV cells, which is converted and increased to 200 V at the dc output voltage. Series-combined connected boost and buck-boost DC-DC converters operate alternatively. This helps to reduce the input ripple current and provide the required 400 Vdc on a sinusoidal PWM three-phase inverter. Analysis of the two series-combined DC-DC converters is presented along with simulation results. Simulations of the series-combined DC-DC converters are presented with an output DC voltage of 200 V and a maximum output load of Po = 600 W.
Buck-Boost/Forward Hybrid Converter for PV Energy Conversion Applications
Directory of Open Access Journals (Sweden)
Sheng-Yu Tseng
2014-01-01
Full Text Available This paper presents a charger and LED lighting (discharger hybrid system with a PV array as its power source for electronic sign indicator applications. The charger adopts buck-boost converter which is operated in constant current mode to charge lead-acid battery and with the perturb and observe method to extract maximum power of PV arrays. Their control algorithms are implemented by microcontroller. Moreover, forward converter with active clamp circuit is operated in voltage regulation condition to drive LED for electronic sign applications. To simplify the circuit structure of the proposed hybrid converter, switches of two converters are integrated with the switch integration technique. With this approach, the proposed hybrid converter has several merits, which are less component counts, lighter weight, smaller size, and higher conversion efficiency. Finally, a prototype of LED driving system under output voltage of 10 V and output power of 20 W has been implemented to verify its feasibility. It is suitable for the electronic sign indicator applications.
Institute of Scientific and Technical Information of China (English)
Wu Xiaobo; Liu Qing; Zhao Menglian; Chen Mingyang
2013-01-01
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 μm CMOS process.Simulation and experiment results show that the transient time of this SIDO buck converter drops to 10 μs while the cross-regulation is reduced to 0.057 mV/mA,when its first load changes from 50 to 100 mA.
Closed-loop analysis and control of a non-inverting buck-boost converter
Chen, Zengshi; Hu, Jiangang; Gao, Wenzhong
2010-11-01
In this article, a cascade controller is designed and analysed for a non-inverting buck-boost converter. The fast inner current loop uses sliding mode control. The slow outer voltage loop uses the proportional-integral (PI) control. Stability analysis and selection of PI gains are based on the nonlinear closed-loop error dynamics incorporating both the inner and outer loop controllers. The closed-loop system is proven to have a nonminimum phase structure. The voltage transient due to step changes of input voltage or resistance is predictable. The operating range of the reference voltage is discussed. The controller is validated by a simulation circuit. The simulation results show that the reference output voltage is well-tracked under system uncertainties or disturbances, confirming the validity of the proposed controller.
Serna-Garcés, S. I.; Jiménez, R. E.; C. A. Ramos-Paja
2013-01-01
This paper proposes an active postfilter based on two Buck converters, connected in parallel, operating in complementary interleaving. In such a configuration the ripple in the load current could be virtually eliminated to improve the power quality in comparison with classical Point-Of-Load (POL) regulators based on a single Buck converter. The postfilter is designed to isolate the load from the main Buck regulator, leading to the proposed three-converter structure named BuckPS. The correct o...
Bifurcation and chaos in high-frequency peak current mode Buck converter
Chang-Yuan, Chang; Xin, Zhao; Fan, Yang; Cheng-En, Wu
2016-07-01
Bifurcation and chaos in high-frequency peak current mode Buck converter working in continuous conduction mode (CCM) are studied in this paper. First of all, the two-dimensional discrete mapping model is established. Next, reference current at the period-doubling point and the border of inductor current are derived. Then, the bifurcation diagrams are drawn with the aid of MATLAB. Meanwhile, circuit simulations are executed with PSIM, and time domain waveforms as well as phase portraits in i L–v C plane are plotted with MATLAB on the basis of simulation data. After that, we construct the Jacobian matrix and analyze the stability of the system based on the roots of characteristic equations. Finally, the validity of theoretical analysis has been verified by circuit testing. The simulation and experimental results show that, with the increase of reference current I ref, the corresponding switching frequency f is approaching to low-frequency stage continuously when the period-doubling bifurcation happens, leading to the converter tending to be unstable. With the increase of f, the corresponding I ref decreases when the period-doubling bifurcation occurs, indicating the stable working range of the system becomes smaller. Project supported by the National Natural Science Foundation of China (Grant No. 61376029), the Fundamental Research Funds for the Central Universities, China, and the College Graduate Research and Innovation Program of Jiangsu Province, China (Grant No. SJLX15_0092).
Directory of Open Access Journals (Sweden)
Latha. S. C
2014-11-01
Full Text Available The portable devices development of semiconductor manufacturing technology, conversion efficiency, power consumption, and the size of devices have become the most important design criteria of switching power converters. For portable applications better conveniences extension of battery life and improves the conversion efficiency of power converters .It is essential to develop accurate switching power converters, which can reduce more wasted power energy. The proposed topology can achieve faster transient responses when the supply voltages are changed for the converter by making use of the feed forward network .With mode select circuit the conduction & switching losses are reduced the positive buck–boost converter operate in buck, buck–boost, or boost converter. By adding feed-forward techniques, the proposed converter can improve transient response when the supply voltages are changed. The designing, modeling & experimental results were verified in MATLAB/ Simulink. The fuzzy logic controller is used as controller.
Digitally Controlled Point of Load Converter with Very Fast Transient Response
DEFF Research Database (Denmark)
Jakobsen, Lars Tønnes; Andersen, Michael Andreas E.
2007-01-01
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...... 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...... three clock cycles from the time the A/D converter result is read by the control algorithm to the time the duty cycle command is updated. A typical POL converter has been built and the experimental results show that the transient response of the converter is very fast. The output voltage overshoot is...
Switched-mode converters (one quadrant)
Barrade, P
2006-01-01
Switched-mode converters are DC/DC converters that supply DC loads with a regulated output voltage, and protection against overcurrents and short circuits. These converters are generally fed from an AC network via a transformer and a conventional diode rectifier. Switched-mode converters (one quadrant) are non-reversible converters that allow the feeding of a DC load with unipolar voltage and current. The switched-mode converters presented in this contribution are classified into two families. The first is dedicated to the basic topologies of DC/DC converters, generally used for low- to mid-power applications. As such structures enable only hard commutation processes, the main drawback of such topologies is high commutation losses. A typical multichannel evolution is presented that allows an interesting decrease in these losses. Deduced from this direct DC/DC converter, an evolution is also presented that allows the integration of a transformer into the buck and the buck–boost structure. This enables an int...
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.
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
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
-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...
Li, Peng; Zhang, Chongxiao; Kim, Junyoung; Yu, Liangyao; Zuo, Lei
2014-04-01
Regenerative semi-active suspensions can capture the previously dissipated vibration energy and convert it to usable electrical energy for powering on-board electronic devices, while achieve both the better ride comfort and improved road handling performance at the same time when certain control is applied. To achieve this objective, the power electronics interface circuit connecting the energy harvester and the electrical loads, which can perform simultaneous vibration control and energy harvesting function is in need. This paper utilized a buck-boost converter for simultaneous semi-active vibration control and energy harvesting with electromagnetic regenerative shock absorber, which utilizes a rotational generator to converter the vibration energy to electricity. It has been found that when the circuit works in discontinuous current mode (DCM), the ratio between the input voltage and current is only related to the duty cycle of the switch pulse width modulation signal. Using this property, the buck-boost converter can be used to perform semi-active vibration control by controlling the load connected between the terminals of the generator in the electromagnetic shock absorber. While performing the vibration control, the circuit always draw current from the shock absorber and the suspension remain dissipative, and the shock absorber takes no additional energy to perform the vibration control. The working principle and dynamics of the circuit has been analyzed and simulations were performed to validate the concept.
一种带耦合电感的交错并联型DC/DC变换器研究%Research on interleaved DC/DC converter in parallel with coupling inductors
Institute of Scientific and Technical Information of China (English)
于澎; 王永攀; 朱忠尼; 宋庆国
2015-01-01
The phenomena existing in each single group of full-bridge converter are the secondary of output transformer shorts out easily after the turning-off of the legging switches, while the loop current exists in the primary under the condition of light load, thus resulting in the control of converter being complex and its low efficiency. To improve the performance of high power converter, and get over the short circuit of the transformer’ s secondary, this paper puts forward a converter topology with output coupling inductors, and then implements the zero current-off and zero voltage-on of the lagging leg’s switching tubes. Next, we analyze the operating principles of the proposed converter circuits and give its key parameter design, and finally perform a experiment. Experiment results agree with those of the theoretical analysis.%在轻负载条件下单组全桥变换器在滞后管关断后存在输出变压器次级短路、初级有环流存在的现象，使得变换器的控制复杂，轻载时变换器效率不高。为了提高大功率变换器性能，解决变压器次级短路问题，提出了一种输出带耦合电感的变换器拓扑，实现了滞后桥臂开关管的零流关断和零压开通。然后，分析了所提出的变换器电路的工作原理，给出了关键参数的设计。最后对变换器进行了实验。实验结果与理论分析一致。
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 ...
An asynchronous finite-state-machine-based buck-boost converter for on-chip adaptive power supply
Fernández, Daniel; Madrenas Boadas, Jordi; Alarcón Cot, Eduardo José
2013-01-01
In this paper we present an asynchronous finite-state machine digital controller co-integrated with an on-chip non-inverting buck-boost power converter with dynamic signal-tracking capabilities. The mostly-digital controller functionally implements a non-PWM zone-wise control law through asynchronous circuitry, thus exhibiting self-timed minimum latency and ultra low power operation due to gate switching activity. Experimental results on a 0.35 lm CMOS technology demonstrate an efficien...
Institute of Scientific and Technical Information of China (English)
Abdolreza Esmaeli; SUN Li; ZHAO Ke; JIANG Bao-jun
2005-01-01
EMI Filter Design and Performance for isolated full bridge buck converter is developed in this paper.In order to design a high performance EMI filter, many issues need to be considered beforehand. Some important issues including accurate model of converter components, parasitic elements, its effect on EMI noise and impedance mismatch are included in this paper. A numerical prediction of EMI/EMC has the potential to evaluate EMI performances at the design stage and before prototyping. It can also help reduce the post-prototype EMC cost by minimizing late redesign and modifications of a design implementation. Saber simulator is used to analyze the EMI noises and EMI filter's performance. Conducted EMI noise measurement and EMI filter design of isolated full bridge buck converter has been achieved while successfully satisfying the FCC class B limits in the frequency range from 150 kHz to 30 MHz. Simulation results are compared with experimental data and the effectiveness of the EMI simulation approach is demonstrated.
One Bridge-type Secondary-side LLC Resonant DC-DC Converter%一种桥型副边LLC谐振直流-直流变换器
Institute of Scientific and Technical Information of China (English)
袁义生; 罗峰; 胡盼安
2014-01-01
A secondary-side LLC resonant converter was proposed. On the primary side, four power switches form a bridge-type construer, and a bulk capacitor is inserted between two primary windings. Then two primary current loops always exist at the same time, and two primary windings flow the same high-frequency resonant current. A voltage-doubling circuit construct is applied on the secondary side. LLC resonance is formed by the magnetic inductance, the leakage inductance and a voltage-doubling capacitanceCc. The power switches can achieve zero-voltage turn-on and are turned off at a little magnetic current. The power diodes can achieve zero-current turn-off and their rated-voltage is equal to output voltage. The operation theory of each stage is analyzed. The conversion gain characteristic, not similar with that of the traditional LLC resonant converter, was also elaborated. A 40~56V input/360V output/rated power 300W prototype was built and tested. Its peak efficiency can over 95.5% in the rated input voltage range. Experimental waveforms also verify the theory and the converter is available.%提出一种副边侧LLC谐振的直流变换器拓扑。原边4个开关管采用一种桥型结构，并利用增加的一个储能电容Cc实现原边同时具有两个电流回路，达到两个变压器原边绕组并联工作而高频谐振电流均流的目的。副边采用倍压结构，利用变压器漏感、励磁电感和倍压电容构成LLC谐振来传递能量。原边开关管能实现零电压开通，且关断时的励磁电流小。副边两个二极管零电流关断，且额定电压为输出电压。分析电路各阶段的工作原理，详细推导电路与传统LLC谐振电路不一样的增益特性。设计一款40~56 V输入/360V输出/额定负载300W的样机，在不同输入下电路最高效率都大于95.5%。实验测试波形验证了电路的正确性及可行性。
R. Bautista-Quintero; H. Taud; M. Marcelino-Aranda; V. M. Hernández-Guzmán; R. Silva-Ortigoza; J. R. García-Sánchez; J. M. Alba-Martínez
2013-01-01
This paper presents a two-stage control design for the “Buck power converter/DC motor” system, which allows to perform the sensorless angular velocity trajectory tracking task. The differential flatness property of the DC-motor model is exploited in order to propose a first-stage controller, which is designed to achieve the desired angular velocity trajectory. This controller provides the voltage profiles that must be tracked by the Buck converter. Then, a second-stage controller is meant to ...
A tapped-inductor buck-boost converter for a multi-DEAP generator energy harvesting system
Dimopoulos, Emmanouil; Munk-Nielsen, Stig
2014-03-01
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; Loh, Poh Chiang
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-blockin...
Li, Qing; Zhang, Xiao-ping; Chen, Qi
2011-12-01
The dynamic performance of a novel Buck-Boost matrix converter (BBMC) based on double-loop control strategy is put forward in this paper. The fundamental principle of BBMC has been elaborated and the method of the double-loop control strategy has been built with Matlab, and then the dynamic performances of BBMC based on the double-loop control strategy are discussed. The results show that the output voltage and frequency can be almost constant with the BBMC and double-loop control strategy despite of the changeable input voltage and frequency. Moreover, a high-quality sine output wave with low harmonic distortion can be directly obtained without filtering. So it can be drawn that the BBMC based on the double-loop control strategy has perfectly dynamic performance and practical importance to the engineering.
An efficiency improved single-phase PFC converter for electric vehicle charger applications
DEFF Research Database (Denmark)
Zhu, Dexuan; Tang, Yi; Jin, Chi;
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....
Tiara Freitas; Paulo Menegáz; Domingos Simonetti
2015-01-01
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. Th...
DC analysis of quasi-resonant buck and forward converters including effects of parasitic elements
Roufberg, Lewis Marlin
1987-01-01
The need for smaller and more efficient power supplies steadily grows. Many power supplies incorporate high-frequency dc-to-dc switching converters to meet these demands. Recently, a new class of switching converters has been introduced which can operate at very high frequencies to further reduce size and increase efficiency. They are called quasi-resonant converters. Previously, the dc characteristics of many of these converters had been determined, assuming ideal components a...
BLDCM Control System Based on Buck-Boost Converter%基于Buck-Boost变换器驱动的无刷直流电动机控制系统
Institute of Scientific and Technical Information of China (English)
孟武胜; 王波; 何博
2011-01-01
An improved topology of brushless DC motor drive with a Buck-Boost converter before 3 phase inverter,The motor can be controlled by technique-multi-loop. This method can reduce switching losses,the inverter size and cost. Effectiveness and feasibility of the proposed control method was verified by MATLAB/Simulink.%提出在无刷直流电动机的驱动三相逆变桥的输入端加前级降压-升压(Buck-Boost)变换器,采用转速和直流母线电流的多环反馈控制方法实现电机的控制.该方法减少了开关损耗,逆变器尺寸和成本.通过MAT-LAB/Simulink仿真验证了该方法的有效性和可行性.
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 μm CMOS process. A small external inductor of 0.47 μH and a capacitor of 4.7 μF 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 μs/V and a fall of 20 μs/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)
Adaptive switching frequency buck DC—DC converter with high-accuracy on-chip current sensor
International Nuclear Information System (INIS)
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 μm 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. (paper)
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 μA) 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 μA 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 μm CMOS processes and requires two external components: 1.2 μF capacitor and 6.8 μH inductor. PMID:26742139
Exploration of Charge Recycling DC-DC Conversion Using a Switched Capacitor Regulator
Directory of Open Access Journals (Sweden)
Mircea R. Stan
2013-07-01
Full Text Available The increasing popularity of DVFS (dynamic voltage frequency scaling schemes for portable low power applications demands highly efficient on-chip DC-DC converters. The primary aim of this work is to enable increased efficiency of on-chip DC-DC conversion for near-threshold operation of multicore chips. The idea is to supply nominal (high off-chip voltage to the cores which are then “voltage-stacked” to generate the near-threshold (low voltages based on Kirchhoff’s voltage law through charge recycling. However, the effectiveness of this implicit down-conversion is affected by the current imbalance among the cores. The paper presents a design methodology and optimization strategy for highly efficient charge recycling on-chip regulation using a push-pull switched capacitor (SC circuit. A dual-boundary hysteretic feedback control circuit has been designed for stacked loads. A stacked-voltage domain with its self-regulation capability combined with a SC converter has shown average efficiency of 78%–93% for 2:1 down-conversion with ILoad (max of 200 mA and workload imbalance varying from 0–100%.
Directory of Open Access Journals (Sweden)
R. Silva-Ortigoza
2013-01-01
differential flatness property of the DC-motor model is exploited in order to propose a first-stage controller, which is designed to achieve the desired angular velocity trajectory. This controller provides the voltage profiles that must be tracked by the Buck converter. Then, a second-stage controller is meant to assure the aforementioned. This controller is based on flatness property of the Buck power converter model, which provides the input voltage to the DC motor. Due to the fact that the two-stage controller proposed uses the average model of the system, as a practical and effective implementation of this controller, a Σ − Δ-modulator is employed. Finally, in order to verify the control performance of this approach, numerical simulations are included.
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. In addition, the effective operational range of the converter is usually limited by the lack of...
Kelkar, S. S.; Lee, F. C.
1984-01-01
Small signal analysis was performed earlier to demonstrate the marked improvement of dynamic properties and stability margins of a switching regulator employing a novel feedforward input filter compensation scheme. A large signal nonlinear recurrent time domain model is presented for the converter to analyse the transient response due to a step input change with and without the presence of the proposed feedforward loop. The results are verified with experimental data.
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)
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.
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 μm 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)
DC-DC-teholähteen suunnittelu full bridge -topologialla
Lapinkangas, Hannu
2011-01-01
Työn tavoitteena oli suunnitella 500 W:inen DC-DC-teholähde, joka toimii full bridge -topologialla. Full bridge -topologialla voidaan saavuttaa erittäin hyvä hyötysuhde ja lähdön häiriöjännite saadaan pysymään pienenä suhteellisen pienellä lähtökapasitanssin määrällä. Teholähteen tulojännitteeksi asetettiin 400 V ja lähtöjännitteeksi 55 V. Hyötysuhteen teholähteellä tulisi olla yli 90 %. Valmista tuotetta teholähteestä ei ollut tarkoitus tehdä, vaan työn tarkoituksena oli saada lisää tietoa ...
Galvanically Isolated Quasi-Z-Source DC–DC Converter With a Novel ZVS and ZCS Technique
DEFF Research Database (Denmark)
Husev, Oleksandr; Liivik, Liisa; Blaabjerg, Frede; Chub, Andrii; Vinnikov, Dmitri; Roasto, Indrek
2015-01-01
This paper focuses on the galvanically isolated quasi-Z-source dc-dc converter with a novel zero voltage and zero current switching technique. The unique feature of the impedance network lies in combining the buck-boost operation capability with the short- and open-circuit immunity of transistors......; at the same time, it can perform zero voltage and zero current switching on the primary side. The boundary conduction mode of the current in the second inductor of the quasi-Z-source network was used along with snubber capacitors in the two out of four transistors and a special control algorithm to...
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.
International Nuclear Information System (INIS)
The upgrades of the Large Hadron Collider (LHC) introduce a significant challenge to the power distribution of the detectors. DC-DC conversion is the preferred powering scheme proposed to be integrated for the CMS tracker to deliver high input voltage levels and performing a step-down conversion nearby the detector modules. In this work, we propose a step-up/step-down powering scheme by performing voltage step up at the CAEN supply unit and voltage step down near the detector. We designed step-up converters and investigate the pixel performance and power loss on the FPIX power distribution system. Tests are performed using the PSI46 pixel readout chips on a forward pixel panel module and the DC-DC converters developed at CERN and Fermilab. Reliability studies include the voltage drop measurements on the readout chips and the power supply noise generated from the converter. Performance studies include pixel noise and threshold dispersion results. Comparison between step-down only and step-up/step-down conversion powering schemes are provided.
Todri, A.; Perera, L.; Rivera, R.; Kwan, S.
2010-12-01
The upgrades of the Large Hadron Collider (LHC) introduce a significant challenge to the power distribution of the detectors. DC-DC conversion is the preferred powering scheme proposed to be integrated for the CMS tracker to deliver high input voltage levels and performing a step-down conversion nearby the detector modules. In this work, we propose a step-up/step-down powering scheme by performing voltage step up at the CAEN supply unit and voltage step down near the detector. We designed step-up converters and investigate the pixel performance and power loss on the FPIX power distribution system. Tests are performed using the PSI46 pixel readout chips on a forward pixel panel module and the DC-DC converters developed at CERN and Fermilab. Reliability studies include the voltage drop measurements on the readout chips and the power supply noise generated from the converter. Performance studies include pixel noise and threshold dispersion results. Comparison between step-down only and step-up/step-down conversion powering schemes are provided.
Todri, A; Rivera, R; Kwan, S; 10.1088/1748-0221/5/12/C12010
2010-01-01
The upgrades of the Large Hadron Collider (LHC) introduce a significant challenge to the power distribution of the detectors. DC-DC conversion is the preferred powering scheme proposed to be integrated for the CMS tracker to deliver high input voltage levels and performing a step-down conversion nearby the detector modules. In this work, we propose a step-up/step-down powering scheme by performing voltage step up at the CAEN supply unit and voltage step down near the detector. We designed step-up converters and investigate the pixel performance and power loss on the FPIX power distribution system. Tests are performed using the PSI46 pixel readout chips on a forward pixel panel module and the DC-DC converters developed at CERN and Fermilab. Reliability studies include the voltage drop measurements on the readout chips and the power supply noise generated from the converter. Performance studies include pixel noise and threshold dispersion results. Comparison between step-down only and step-up/step-down conversi...
DEFF Research Database (Denmark)
Tang, Yi; Zhu, Dexuan; Jin, Chi;
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...... 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...
PARÇACIK SÜRÜ OPTİMİZASYONU İLE FOTOVOLTAİK SİSTEMLERDE KULLANILAN DC-DC DÖNÜŞTÜRÜCÜNÜN KONTROLÜ
Öztürk, Ali; ALKAN, Selman
2013-01-01
Photovoltaic (PV) system is known as a system generating electrical energy from solar energy. DC-DC converters is of great importance in terms of the system stability and efficiency in PV system. The sun angle, weather conditions such as temperature and load changes in the system cause the change of voltage values. It is important that the output voltage of DC-DC converter used in PV systems remain constant at the desired value and is retained in this value. So, it would have been easier to c...
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.
Latha. S. C; Dr. Venugopal .N
2014-01-01
The portable devices development of semiconductor manufacturing technology, conversion efficiency, power consumption, and the size of devices have become the most important design criteria of switching power converters. For portable applications better conveniences extension of battery life and improves the conversion efficiency of power converters .It is essential to develop accurate switching power converters, which can reduce more wasted power energy. The proposed topology can ...
Reset-sensing quasi-V2 single-inductor multiple-output buck converter with reduced cross-regulation
Lee, ATL; Tan, SC; Hui, SYR; Chan, PCH; Sin, JKO
2015-01-01
This paper proposes a reset-sensing quasi-V2 single-inductor multiple-output (SIMO) converter with minimal cross-regulation. The conventional quasi-V2 sensing scheme in SIMO converters suffers from serious cross-regulation which is primarily induced by the load differentiation with unbalanced loads. It is shown that the proposed reset-sensing quasi-V2 control scheme can significantly reduce cross-regulation by completely discharging the feed-forward sensing node to zero volts during the idle ...
Institute of Scientific and Technical Information of China (English)
张希; 许建平; 包伯成; 贺明智
2014-01-01
当输出电容等效串联电阻(equivalent series resistance，ESR)较小时，固定关断时间控制(fixed off-time，FOT)控制Buck变换器可能工作在不稳定的混沌状态。提出FOT控制Buck 变换器的斜坡补偿技术，通过采样电感电流信息对输出电容电压进行电压斜坡补偿，实现了低 ESR 输出电容FOT控制Buck变换器的稳定工作。分析斜坡补偿的作用机理，给出确保变换器稳定工作时斜坡补偿电压斜率的临界值。建立斜坡补偿FOT控制Buck变换器的离散映射模型，研究斜坡补偿电压斜率作为分岔参数时斜坡补偿FOT控制Buck 变换器的动力学行为。研究结果表明，斜坡补偿有效拓宽了变换器输出电容 ESR 的稳定工作范围，通过斜坡补偿技术，输出电容ESR较小时FOT控制Buck变换器也能稳定正常工作。实验结果验证了理论分析的正确性。%The fixed off-time (FOT) controlled buck converter often operates in an unstable and chaotic state when the output capacitor has a low equivalent series resistance (ESR). By sensing inductor current information of main circuits for compensating the slope of output capacitor voltage, a ramp compensation technique of FOT controlled buck converter is proposed, which realizes that the converter is in stable and normal operation when a low ESR output capacitor is used. The action mechanism of the ramp compensation technique is analyzed, and the critical slope of compensation ramp voltage to ensure the converter stable operation is achieved quantitatively. The discrete-time map model of FOT controlled buck converter with ramp compensation is established, upon which the dynamical behaviors of the converter are investigated by taking the slope of compensation ramp voltage as the bifurcation parameter. The results indicate that the ramp compensation effectively extends the stable operating range of the output capacitor ESR of the converter, and the ramp compensation
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...
Physics of Failure Models for Capacitor Degradation in DC-DC Converters
National Aeronautics and Space Administration — This paper proposes a combined energy-based model with an empirical physics of failure model for degradation analysis and prognosis of electrolytic capacitors in...
Usign Planar Transformers in Soft Switching DC/DC Power Converters
Directory of Open Access Journals (Sweden)
Gabriel Kacor
2004-01-01
Full Text Available In recent years, the demand for wide applications of highly regulated, reliable power supplies, and the desire to have smaller size, lighter weight and higher efficiency of power electronics systems has been increased. The tallest and heaviest components on printed-circuit-boards are often magnetic components. The answer for miniaturization and material performance can be planar magnetic technology. This paper focuses on the power planar magnetic circuits, with respect to application possibilities of these alternative and attractive magnetic components in modern, soft switching, low profile power supplies.
The control algorithm DC-DC converter device for field weakening
Костенко, Іван Олександрович; Петренко, Олександр Миколайович
2015-01-01
In order to improve the energy efficiency of rolling stock and its characteristics are taken Various regulatory tools. In particular, improving circuit design, the transition to pulse traction motor control system, the use of key semiconductor devices with lower internal losses, and so on. Field weakening mode traction engines is one of the main modes of the electric rolling stock. In the previous article, the authors were reviewed in detail to improve the system weakening of the field using ...
Multistability and hidden attractors in a multilevel DC/DC converter
DEFF Research Database (Denmark)
Zhusubaliyev, Zhanybai T.; Mosekilde, Erik
2015-01-01
An attracting periodic, quasiperiodic or chaotic set of a smooth, autonomous system may be referred to as a "hidden attractor" if its basin of attraction does not overlap with the neighborhood of an unstable equilibrium point. Historically, this condition has implied that the basin of attraction...... produce complicated structures of attracting and repelling states organized around the basic switching cycle. This leads us to suggest the existence of hidden attractors in such systems as well. In this case, the condition will be that the basin of attraction does not overlap with the fixed point...
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.
The use of power DC-DC converters and gyrator structures for energy processing
Martínez García, 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 ...
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
Roermund, Arthur; Baschirotto, Andrea
2012-01-01
The book contains the contribution of 18 tutorials of the 20th workshop on Advances in Analog Circuit Design. Each part discusses a specific to-date topic on new and valuable design ideas in the area of analog circuit design. Each part is presented by six experts in that field and state of the art information is shared and overviewed. This book is number 20 in this successful series of Analog Circuit Design, providing valuable information and excellent overviews of Low-Voltage Low-Power Data Converters - Chaired by Prof. Anderea Baschirotto, University of Milan-Bicocca Short Range Wireless Front-Ends - Chaired by Prof. Arthur van Roermund, Eindhoven University of Technology Power management and DC-DC - Chaired by Prof. M. Steyaert, Katholieke University Leuven Analog Circuit Design is an essential reference source for analog circuit designers and researchers wishing to keep abreast with the latest development in the field. The tutorial coverage also makes it suitable for use in an advanced design.
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
DC-DC konverter zasnovan na tehnologiji laganog prebacivanja za primjene u auto industriji
Mahalingam, Prabhakar
2015-01-01
DC-DC konverteri zasnovani na tehnologiji ćelija naponskog množila predloženi su u ovome članku. Predloženi konverteri pružaju zahtjevanu visoku voltažu be uporabe transformatora. Slijedom toga, dobivamo kompaktni konverter sa visokom gustoćom energije. Predložena topologija ima veću efikasnost zahvaljujući laganon predacivanju aktivnih komponenti. Eksperimentalni rezultati pokazuju da konverter radi sa maksimalno 95% korisnosti ujedno pružajući i dobru regulaciju tereta.
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
Institute of Scientific and Technical Information of China (English)
刘啸天; 周国华; 李振华; 陈兴
2015-01-01
The operation principle of digital voltage-mode controlled buck converter with dual-edge modulation is analyzed in this paper. Based on the state equation of buck converter and six possible evolutions in one switching cycle, the discrete iterative-map model of digital voltage-mode controlled buck converter with dual-edge modulation is established. Ignoring the quantization error of analog-digital converter and on the basis of its discrete iterative-map model, the nonlinear dynamical behavior of digital voltage-mode controlled buck converter with dual-edge modulation is investigated in detail. Taking the input voltage and the load resistance as bifurcation parameters, the output voltage bifurcation diagram and the inductor current bifurcation diagram are plotted. Through analyzing the bifurcation diagrams, it is indicated that there are two kinds of similar but different Hopf bifurcation phenomena. By use of Poincar´e section, time-domain simulation waveforms and phase portraits, two different Hopf bifurcations and low-frequency oscillation phenomena are compared and studied. Observing the inductor current and capacitor voltage waveforms respectively, it is obviously found that their oscillation frequencies and amplitudes are different, the shapes of two Poincar´e sections and phase portraits are also different. In order to verify the correctness of the simulation and theoretical analysis, the eigenvalues of Jacobian matrix of the discrete iterative map model are introduced and solved in two kinds of stable evolutions. Through analyzing variation of eigenvalues of Jacobi matrix with input voltage, the existence and difference of two kinds of Hopf bifurcation phenomena are proved theoretically. Moreover, it is observed in this paper that the odd period-doubling bifurcation phenomenon exists in digital voltage-mode controlled buck converter with dual-edge modulation for the first time, where the operation state of the buck converter turns from period-one into period
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
Bidirectional converter interface for a battery energy storage test bench
DEFF Research Database (Denmark)
Trintis, Ionut; Thomas, Stephan; Blank, Tobias;
2011-01-01
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...
2011-09-06
... COMMISSION In the Matter of Certain DC-DC Controllers and Products Containing Same; Notice of Institution of... ``Richtek''). 75 FR 446-47. The complaint, as amended, alleged violations of section 337 of the Tariff Act... (EDIS) at http://edis.usitc.gov/ . Hearing-impaired persons are advised that information on the...
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.
Configuración y prueba de convertidores DC/DC para prácticas de laboratorio
De Evan de Marcos, Cristina
2015-01-01
Este proyecto consiste en el diseño e implementación de convertidores DC/DC a partir del dispositivo Semiteach-‐IGBT para docencia en Electrónica de Potencia. De este modo, los alumnos pueden realizar pruebas experimentales en una plataforma real de los contenidos teóricos vistos en clase o simulados. Mediante técnicas de Modulación por Ancho d...
Analysis and Design of Embedded Controlled Parallel Resonant Converter
Directory of Open Access Journals (Sweden)
P. CHANDRASEKHAR
2009-07-01
Full Text Available Microcontroller based constant frequency controlled full bridge LC parallel resonant converter is presented in this paper for electrolyser application. An electrolyser is a part of renewable energy system which generates hydrogen from water electrolysis. The DC power required by the electrolyser system is supplied by the DC-DC converter. Owing to operation under constant frequency, the filter designs are simplified and utilization of magnetic components is improved. This converter has advantages like high power density, low EMI and reduced switching stresses. DC-DC converter system is simulated using MATLAB, Simulink. Detailed simulation results are presented. The simulation results are compared with the experimental results.
A Single Phase to Three Phase PFC Half-Bridge Converter Using BLDC Drive with SPWM Technique.
Directory of Open Access Journals (Sweden)
Srinu Duvvada
2014-07-01
Full Text Available In this paper, a buck half-bridge DC-DC converter is used as a single-stage power factor correction (PFC converter for feeding a voltage source inverter (VSI based permanent magnet brushless DC motor (BLDC drive. The front end of this PFC converter is a diode bridge rectifier (DBR fed from single-phase AC mains. The BLDC is used to drive a compressor load of an air conditioner through a three-phase VSI fed from a controlled DC link voltage. The speed of the compressor is controlled to achieve energy conservation using a concept of the voltage control at DC link proportional to the desired speed of the BLDC. Therefore the VSI is operated only as an electronic commutator of the BLDC. The stator current of the BLDC during step change of reference speed is controlled by a rate limiter for the reference voltage at DC link. The proposed BLDC drive with voltage control based PFC converter is designed, modeled and its performance is simulated in Matlab-Simulink environment for an air conditioner compressor driven through a 1.5 kW, 1500 rpm BLDC motor. The evaluation results of the proposed speed control scheme are presented to demonstrate an improved efficiency of the proposed drive system with PFC feature in wide range of the speed and an input AC voltage.
Isolated Boost Converter with Bidirectional Operation for Supercapacitor Applications
DEFF Research Database (Denmark)
Hernandez Botella, Juan Carlos; Mira Albert, Maria del Carmen; Sen, Gökhan;
2013-01-01
This paper presents an isolated bidirectional dc/dc converter based on primary parallel isolated boost converter (PPIBC). This topology is an efficient solution in low voltage high power applications due to its ability to handle high currents in the low voltage side. In this paper, the converter...
A New Hard Switching Bidirectional Converter With High Power Density
Bahador Fani; Majid Delshad; Daryoosh Nazarpour
2010-01-01
In this paper, a new isolated dc-dc bidirectional converter is proposed. This converter consists of two transformers (flyback and forward) and only one switch in primary side and one switch in secondary side of transformers. In this converter energy transfers to the output in both on and off switch states so power density of this converter is high This converter controlled by PWM signal. Also this converter operates over a wide input voltage range. Theoretical analysis is presented and compu...
Quasi-Periodicity and Border-Collision Bifurcations in a DC-DC Converter with Pulsewidth Modulation
DEFF Research Database (Denmark)
Zhusubalaliyev, Zh. T.; Soukhoterin, E.A.; Mosekilde, Erik
2003-01-01
border-collision bifurcations (BCB) on a two-dimensional torus. The arrangement of the resonance domains within the parameter plane is related to the Farey series, and their internal structure is described. It is shown that transitions to chaos mainly occur through finite sequences of BCB. Some other...
Martínez García, 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 ...
Martínez García, Herminio; Cosp Vilella, Jordi
2014-01-01
Este artículo ofrece una clasificación de las estructuras giradoras de potencia conmutadas de alta eficiencia (high efficiency switching power-gyrator structures), y su uso como células para el procesado de energía en instalaciones solares fotovoltaicas. Teniendo en cuenta las propiedades de estas topologías presentadas en el artículo, su inclusión en instalaciones solares, permite aumentar el rendimiento de toda la instalación. Así pues, el diseño, simulación e implementación de un girador d...
Martínez García, 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 ...
1V.Chaitanya,P.G.scholar,; 2 J.S.V. Siva Kumar,Sr.Asst.Professor,
2015-01-01
: 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 invo...
An Improved Power Quality BIBRED Converter-Based VSI-Fed BLDC Motor Drive
Singh, Bhim; Bist, Vashist
2014-01-01
This paper presents an IHQRR (integrated high-quality rectifier regulator) BIBRED (boost integrated buck rectifier energy storage DC-DC) converter-based VSI (voltage source inverter)-fed BLDC (brushless DC) motor drive. The speed control of BLDC motor is achieved by controlling the DC link voltage of the VSI using a single voltage sensor. This allows VSI to operate in fundamental frequency switching mode for electronic commutation of BLDC motor which reduces the switching losses due to high-frequency switching used in conventional approach of PWM (pulse width modulation)-based VSI-fed BLDC motor drive. A BIBRED converter is operated in a dual-DCM (discontinuous conduction mode) thus using a voltage follower approach for PFC (power factor correction) and DC link voltage control. The performance of the proposed drive is evaluated for improved power quality over a wide range of speed control and supply voltage variation for demonstrating the behavior of proposed drive. The power quality indices thus obtained are within the recommended limits by international PQ (power quality) standards such as IEC 61000-3-2.
Directory of Open Access Journals (Sweden)
Venmathi M
2014-07-01
Full Text Available In this paper analysis of an efficient topology of the three-port full bridge dc-dc converter is presented. This topology is promising with the view points of centralised control, compact design as it is capable of interfacing many numbers of ports with less number of switches, low cost, simple and fast power flow management with reduced conversion process. In a stand-alone system this topology is used to interface renewable energy sources and the load along with the energy storage device. Thus the proposed topology interfaces three ports: as one source port, one bidirectional storage port and an isolated output port. The key feature of this converter is that it performs buck-boost operation on the input port side to obtain power balance in the system with the centralised controller. The centralised controller was implemented by using proportional Integral (PI controller. Such that it is used to track maximum power from the Photovoltaic (PV system and to regulate output voltage by controlling the charging and the discharging characteristics of the battery. Zero voltage switching (ZVS is also achieved in all the switches by using the energy stored in the leakage inductance of the transformer, output filter inductance and capacitance.
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..
DEFF Research Database (Denmark)
Rødgaard, Martin Schøler; Andersen, Thomas; Meyer, Kaspar Sinding;
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...
Analysis and Implementation of Efficient BLDC Motor Drive with Different Converter Systems
Angeline Jayachandran*1,; Mrs. G.R.P Lakshmi2
2014-01-01
This Paper deals with analysis of efficient BLDC motor drive with various converter systems. Performance of the drive system is compared based on THD and PF at the AC mains with the following converter topology: Conventional DC-DC converter, SEPIC and CSC converter. The complete drive system is designed and modeled in MATLAB/Simulink environment for speed control over a wide range.
On-Chip Buck-Boost Power Supply for Power Amplifiers
Oroug, Ole
2006-01-01
The increasing use of low voltage portable devices and growing requirements of functionalities embedded into such devices, efficient power management techniques are needed for longer battery life. The efficiency of battery-operated portable applications can be improved by increasing the efficiency of power amplifiers. By dynamically changing the supply voltage from the fixed battery supply using a DC-DC converter, the power amplifier can be operated with high efficiency during power back-off....
Low-power PFC and forward converters : methods to improve performance
Tuomainen, Vesa
2004-01-01
The number of power electronic appliances is growing. Power electronic converters can be used to convert the ac line voltage to a dc voltage, and further through dc-dc conversion stages to desired dc voltages for different loads. This Thesis deals with three single-stage power factor correction converters and a forward type dc-dc converter. Single-stage converters can be considered as low cost solutions for power factor correction. This is because only one active switching stage is used i...
LLC resonant half-bridge circuit design with DC-DC%LLC谐振半桥DC-DC电路设计
Institute of Scientific and Technical Information of China (English)
杨磊; 吴晓光; 羊彦
2013-01-01
LED drive power level after the DC-DC constant current circuit using LLC resonant half-bridge topology structure, and through the output current and voltage feedback loop to achieve constant current limiting function.LLC resonant half-bridge DC-DC constant current circuit power part comprises a resonant circuit and the output of the rectifier circuit, the control part chip power supply circuit, the control chip peripheral circuit, an output feedback loop, the test shows that the system has stable output can be good, long time working with high efficiency.%LED驱动电源的后级DC-DC恒流电路采用LLC谐振半桥的拓扑结构,并通过输出的电流电压双环反馈来实现恒流限压功能.LLC谐振半桥DC-DC恒流电路的功率部分包括了谐振电路和输出整流电路,控制部分有芯片供电电路、控制芯片外围电路、输出反馈回路等,经试验证明该系统输出稳定好,能够长时间高效工作.
Directory of Open Access Journals (Sweden)
Constance Murray
2008-12-01
Full Text Available Paul Buck passed away on January 16, 2008. Respected and admired by his colleagues and friends, he left a legacy of lifelong commitment to ecology and botany. Paul was a founding member of the Board of Directors of the Oklahoma Native Plant Society in 1987, and, after serving on its board for several subsequent terms, he was the second recipient of the ONPS Service Award.
Constance Murray
2008-01-01
Paul Buck passed away on January 16, 2008. Respected and admired by his colleagues and friends, he left a legacy of lifelong commitment to ecology and botany. Paul was a founding member of the Board of Directors of the Oklahoma Native Plant Society in 1987, and, after serving on its board for several subsequent terms, he was the second recipient of the ONPS Service Award.
International Nuclear Information System (INIS)
This book concentrates on switch mode power supply. It has four parts, which are introduction of switch mode power supply with DC-DC converter such as Buck converter boost converter, Buck-boost converter and PWM control circuit, explanation for SMPS with DC-DC converter modeling and power mode control, resonance converter like resonance switch, converter, multi resonance converter and series resonance and parallel resonance converters, basic test of SMPS with PWM control circuit, Buck converter, Boost converter, flyback converter, forward converter and IC for control circuit.
Quasi-Y-Source Boost DC–DC Converter
DEFF Research Database (Denmark)
Siwakoti, Yam Prasad; Blaabjerg, Frede; Loh, Poh Chiang
2015-01-01
In this letter, a new topology called “quasi-Y-source dc-dc converter” is presented. It inherits all the advantages of the original Y-source converter. In addition, the new topology draws a continuous current from the source, which is definitely more appropriate for most renewable sources. It als...... has dc-current-blocking capacitors, which will definitely help to prevent the coupled inductor core from saturation. Experimental testing has proven the validity of the proposed network and its application as a high boost dc-dc converter....
EMI Prediction of Switching Converters
Trinchero, Riccardo; Stievano, Igor Simone; Canavero, Flavio
2015-01-01
This paper addresses the simulation of the conducted electromagnetic interference produced by circuits with periodically switching elements. The proposed method allows for the computation of their steady-state responses by means of augmented linear time-invariant equivalents built from circuit inspection only, and standard tools for circuit analysis. The approach is demonstrated on a real dc-dc boost converter by comparing simulation results with real measurements
Viejo de Frutos, Miriam del; Alou Cervera, Pedro; García Suárez, Oscar; Oliver Ramírez, Jesús Angel; Cobos Márquez, José Antonio
2010-01-01
Una frecuencia de conmutación de 5MHz permite la integración en un chip de un convertidor DC/DC de baja potencia (10W). Aunque a esta frecuencia de conmutación es posible emplear un control modo tensión con un ancho de banda de 1MHz, los efectos parásitos y la robustez del sistema no permiten esa frecuencia de ancho de banda tan elevada. En esta publicación se propone una técnica de control que optimiza la respuesta dinámica de convertidores DC/DC de elevada frecuencia de conmutació...
Improved Forward Topologies for DC-DC applications with Built-in Input Filter
Leu, Ching-Shan
2006-01-01
Among PWM power conversion topologies, the single-switch forward topology is the one that has been most widely used for decades. Its popularity has been based on many factors, including its low cost, circuit simplicity and high efficiency. However, several issues need to be addressed when using the forward converter such as the core reset, the voltage spikes caused by the transformer leakage inductance, and the pulsating input current waveform. The transformer is driven in a unidirecti...
Isolated Bidirectional DC–DC Converter for SuperCapacitor Applications
DEFF Research Database (Denmark)
Dehnavi, Sayed M. D.; Sen, Gökhan; Thomsen, Ole Cornelius;
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...
Institute of Scientific and Technical Information of China (English)
刘福鑫; 阮洁; 阮新波
2012-01-01
Multi-port DC/DC converters（MPC） can be combined with multiple uni-directional DC/DC converters and bidirectional DC/DC converters into one configuration,which are of potential interest in applications such as renewable power systems and electric vehicle power systems,featuring simpler structure,lower cost and more flexible control.In this paper,available MPC were classified into different types,and the characteristics of each type were illustrated.The unipolar pulsating source cells（UPSC） were extracted from the conventional bidirectional converters;the approach to construct MPC with UPSC and buffer cells was proposed;and corresponding rules for combination and cascade of PSCs and buffer cells were given.Finally,five synthesizing rules for MPC were generalized and a series of MPC topologies were derived.%多端口直流变换器（multi-port DC/DC converters,MPC）可应用于新能源供电系统与电动汽车供电系统,它将系统中原有的多个单向和双向直流变换器在电路结构上实现合并,具有结构简单、成本低、控制灵活等优点。对现有的MPC进行分类,指出每种类型变换器的特点。从基本的双向直流变换器中提取出双向单极性脉冲电源单元,提出采用脉冲电源单元和缓冲单元组合的方法构建MPC,给出脉冲电源单元组合规则及其与缓冲单元的级联规则,总结归纳出5种不同类型多端口变换器的生成规则,进而推导出一系列MPC拓扑。
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......The large scale integration of renewable energy sources requires suitable energy storage systems to balance energy production and demand in the electrical grid. Bidirectional fuel cells are an attractive technology for energy storage systems due to the high energy density of fuel. Compared to...... 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...
High Efficiency Boost Converter with Three State Switching Cell
DEFF Research Database (Denmark)
Klimczak, Pawel; Munk-Nielsen, Stig
2009-01-01
The boost converter with the three-state switching cell seems to be a good candidate for a dc-dc stage for non-isolated generators based on alternative energy sources. It provides a high voltage gain, a reduced voltage stress on transistors and limited input current ripples. In this paper the focus...
An Effective Wind Energy System based on Buck-boost Controller
Directory of Open Access Journals (Sweden)
N. Prakash
2013-06-01
Full Text Available In Domestic Wind Machines, if the wind speed is low, the output voltage is not sufficient to charge the battery as it is lower than the rated charging voltage of the battery. This limits the overall efficiency of the Wind Machine to 20%. This study proposed to design and develop a Buck Boost Controller for the effective utilization of the wind machine. By implementing a controller based Buck Boost converter, the voltage produced at the lower wind speeds can also be utilized effectively by boosting it to the rated charging voltage of the battery. Also if the wind speed is high (>14 m/s, the DC output voltage will increase to more than 65 V. The converter bucks this high voltage to the nominal battery charging voltage (52 V, thereby protecting the battery from over charging voltage. Thus the effective utilization of the wind machine has been achieved by the use of the proposed Buck Boost Controller.
Directory of Open Access Journals (Sweden)
M. Hemachandran
2014-08-01
Full Text Available In this study multi port AC/DC-DC single stage power electronics converter proposed for grid power supply. The topology includes reduced number of active element and passive element. Passive element is used to provide to achieve improved voltage gain and to reduce the voltage stress of input side switches. The active-clamp circuits are used to recycle the energy stored in the leakage inductors and to improve the system performances. Here two input port (wind and battery unit and output port connected to dc grid, battery act as charge unit and source. Efficient wind power conversion is achieved by PFC boost dc-dc converter. Controlled and high step up voltage is supplied to multi-port converter from wind source.
Commutation Processes in Multiresonant ZVS Bridge Converter
Directory of Open Access Journals (Sweden)
Miroslaw Luft
2008-01-01
Full Text Available The analysis of the multiresonant ZVS DC/DC bridge converter is presented. The control system of the converter is basedon the method of frequency control at the constant time of transistor turn-off with a phase shift. The operation of the circuit is givenand the operating range of the converter is defined where ZVS switching operation is assured. Control characteristics are given andthe converter’s efficiency is defined. The circuit’s operation is analysed on the basis of results of the converter simulation tests using Simplorer programme.
A New Hard Switching Bidirectional Converter With High Power Density
Directory of Open Access Journals (Sweden)
Bahador Fani
2010-01-01
Full Text Available In this paper, a new isolated dc-dc bidirectional converter is proposed. This converter consists of two transformers (flyback and forward and only one switch in primary side and one switch in secondary side of transformers. In this converter energy transfers to the output in both on and off switch states so power density of this converter is high This converter controlled by PWM signal. Also this converter operates over a wide input voltage range. Theoretical analysis is presented and computer simulation and experimental results verify the converter analysis.
DEFF Research Database (Denmark)
Beltran, H.; Perez, E.; Chen, Zhe;
2009-01-01
This paper describes a Fixed Maximum Power Point analog control used in a step-down Pulse Width Modulated power converter. The DC/DC converter drives a DC motor used in small water pumping installations, without any electric storage device. The power supply is provided by PV panels working around...
A High Power Density Three-level Parallel Resonant Converter for Capacitor Charging
Sheng, Honggang
2009-01-01
This dissertation proposes a high-power, high-frequency and high-density three-level parallel resonant converter for capacitor charging. DC-DC pulsed power converters are widely used in military and medical systems, where the power density requirement is often stringent. The primary means for reducing the power converter size has been to reduce loss for reduced cooling systems and to increase the frequency for reduced passive components. Three-level resonant converters, which combine the mer...
Improved Power Electronic Converter Topology Using a Variable Inductor for Electric Vehicles
Beraki, Mebrahtom Woldelibanos
2015-01-01
The design and selection of power inductor plays an essential role in the overall system performance as well as the size of power converter topologies. Therefore, this project is concentrated on the optimal power converters topologies definition based on variable inductor and focus is given to the design, implementation and testing of the DC-DC converters for improving the size and efficiency of power converters particularly for traction application. Both the design, modelling, simulation an...
Analysis and Implementation of Efficient BLDC Motor Drive with Different Converter Systems
Directory of Open Access Journals (Sweden)
Angeline Jayachandran*1,
2014-04-01
Full Text Available This Paper deals with analysis of efficient BLDC motor drive with various converter systems. Performance of the drive system is compared based on THD and PF at the AC mains with the following converter topology: Conventional DC-DC converter, SEPIC and CSC converter. The complete drive system is designed and modeled in MATLAB/Simulink environment for speed control over a wide range.
Active Clamped ZVS Forward Converter With Soft-Switched Synchronous Rectifier
AÇIK, Adnan; ÇADIRCI, Işık
2002-01-01
This paper presents the analysis, design and implementation of an active-clamped, ZVS forward converter equipped with a soft-switched synchronous rectifier (ACFC-SR) proposed for high-efficiency, low output voltage dc-dc converter applications. The converter efficiency is maximized due to the soft-switching of the main, active clamp, synchronous rectifier and freewheeling MOSFET switches. The operating principles of the ACFC-SR are analyzed in detail and the converter performance is ...
High Frequency Soft Switching Of PWM Boost Converter Using Auxiliary Resonant Circuit
C. P. Sai Kiran; M. Vishnu Vardhan
2014-01-01
This thesis presents High frequency Soft Switching DC-DC boost Converter. The circuit consists of a general Boost Converter with an additional resonant circuit which has a switch, inductor, capacitor and a diode.In general Boost Converter circuits have snubber circuits where switching losses are dissipated in external passive resistors; which is known as hard switching. As the switching frequency of PWM converters is increased its switching losses and conduction losses also in...
Bidirectional soft-switching converter-fed DC motor drives
Ching, TW; Chan, CC; Chau, KT
1998-01-01
Two new soft-switching DC-DC power converters, with the capabilities of bidirectional power flow and soft-switching (either zero-voltage transition or zero-current transition) are developed for DC motor drives. The proposed bidirectional zero-voltage-transition power converter possesses the definite advantages that both main transistors and rectifiers can switch with zero-voltage switching (ZVS) and unity device stresses during both motoring and regenerating modes of operation, while both the...