Showing papers on "Voltage published in 2007"
TL;DR: The results show that the predictive method controls very effectively the load current and performs very well compared with the classical solutions.
Abstract: This paper presents a predictive current control method and its application to a voltage source inverter. The method uses a discrete-time model of the system to predict the future value of the load current for all possible voltage vectors generated by the inverter. The voltage vector which minimizes a quality function is selected. The quality function used in this work evaluates the current error at the next sampling time. The performance of the proposed predictive control method is compared with hysteresis and pulsewidth modulation control. The results show that the predictive method controls very effectively the load current and performs very well compared with the classical solutions
1,387 citations
TL;DR: In this paper, the authors presented a small (component volume 1 cm3, practical volume 1 5 cm3) electromagnetic generator utilizing discrete components and optimized for a low ambient vibration level based upon real application data.
Abstract: Vibration energy harvesting is receiving a considerable amount of interest as a means for powering wireless sensor nodes This paper presents a small (component volume 01 cm3, practical volume 015 cm3) electromagnetic generator utilizing discrete components and optimized for a low ambient vibration level based upon real application data The generator uses four magnets arranged on an etched cantilever with a wound coil located within the moving magnetic field Magnet size and coil properties were optimized, with the final device producing 46 µW in a resistive load of 4 k? from just 059 m s-2 acceleration levels at its resonant frequency of 52 Hz A voltage of 428 mVrms was obtained from the generator with a 2300 turn coil which has proved sufficient for subsequent rectification and voltage step-up circuitry The generator delivers 30% of the power supplied from the environment to useful electrical power in the load This generator compares very favourably with other demonstrated examples in the literature, both in terms of normalized power density and efficiency
1,313 citations
TL;DR: In this paper, a method was described in which crystalline silicon can be used as a practical anode material for lithium-ion batteries, and a cycling method was demonstrated in which the silicon is first partially converted to amorphous silicon, in situ, during conditioning cycles.
Abstract: A method is described in which crystalline silicon can be used as a practical anode material for lithium-ion batteries. Commercial lithium-ion cells are typically charged at a constant current to a fixed voltage and then are held by the charger at constant voltage until the current decreases to a certain value (also known as constant current/constant voltage or CCCV charging). It is first shown that CCCV charging can be used to reversibly cycle crystalline silicon and limit its capacity. A cycling method is then demonstrated in which crystalline silicon is first partially converted to amorphous silicon, in situ, during conditioning cycles. After the conditioning cycles the silicon can be cycled normally, using CCCV cycling limits, with good coulombic efficiency and little overlithiation during the first cycle.
1,049 citations
TL;DR: The aim of this paper is to propose a flexible active power control based on a fast current controller and a reconfigurable reference current selector that facilitates multiple choices for fault ride through by simply changing the reference selection criteria.
Abstract: The increasing penetration of distributed power generation into the power system leads to a continuous evolution of grid interconnection requirements. In particular, active power control will play an important role both during grid faults (low-voltage ride-through capability and controlled current injection) and in normal conditions (reserve function and frequency regulation). The aim of this paper is to propose a flexible active power control based on a fast current controller and a reconfigurable reference current selector. Several strategies to select the current reference are studied and compared using experimental results that are obtained during an unsymmetrical voltage fault. The results of the analysis allow selection of the best reference current in every condition. The proposed methods facilitate multiple choices for fault ride through by simply changing the reference selection criteria.
690 citations
TL;DR: The perturbation theory for calculating the piezoelectric potential distribution in a nanowire (NW) as pushed by a lateral force at the tip produces a result that is within 6% from the full numerically calculated result using the finite element method.
Abstract: We have applied the perturbation theory for calculating the piezoelectric potential distribution in a nanowire (NW) as pushed by a lateral force at the tip. The analytical solution given under the first-order approximation produces a result that is within 6% from the full numerically calculated result using the finite element method. The calculation shows that the piezoelectric potential in the NW almost does not depend on the z-coordinate along the NW unless very close to the two ends, meaning that the NW can be approximately taken as a “parallel plated capacitor”. This is entirely consistent to the model established for nanopiezotronics, in which the potential drop across the nanowire serves as the gate voltage for the piezoelectric field effect transistor. The maximum potential at the surface of the NW is directly proportional to the lateral displacement of the NW and inversely proportional to the cube of its length-to-diameter aspect ratio. The magnitude of piezoelectric potential for a NW of diameter 50 nm and length 600 nm is 0.3 V. This voltage is much larger than the thermal voltage (25 mV) and is high enough to drive the metal-semiconductor Schottky diode at the interface between atomic force microscope tip and the ZnO NW, as assumed in our original mechanism for the nanogenerators. Developing novel technologies for wireless nanodevices and nanosystems is of critical importance for applications in biomedical sensing, environmental monitoring, and even personal electronics. Miniaturization of a power package and self-powering of these tiny devices are some key challenges for their applications. Various approaches have been developed for harvesting energy from the environment based on approaches such as thermoelectricity and piezoelectricity. Innovative nanotechnologies are being developed for converting mechanical energy (such as body movement, muscle stretching), vibration energy (such as acoustic/ultrasonic wave), and hydraulic energy (such as body fluid and blood flow) into electric energy that will be used to power nanodevices that operate at low power. Recently, using piezoelectric ZnO nanowire (NW) arrays, a novel approach has been demonstrated for converting nanoscale mechanical energy into electric energy. 1-3 The single nanowire nanogenerator (NG) relies on the bending of a NW by a conductive atomic force microscope (AFM) tip, which transfers the displacement energy from the tip to the elastic bending energy of the NW. The coupled piezoelectric and semiconducting properties of the NW perform a charge creation, accumulation, and discharge process. Most recently, this approach has been extensively developed to produce continuous direct-current output with the use of aligned NWs that were covered by a zigzag top electrode, and the nanogenerator was driven by ultrasonic wave, establishing the platform of producing usable power output for nanodevices by harvesting energy from the environment. 4 Furthermore, based on the coupled piezoelectric and semiconducting properties of the NW, a new field of nanopiezotronics has been created, 5,6 which is the basis for fabricating piezoelectric field effect transistors, 7 piezoelectric diode, 8 piezoelectric force/humidity/chemical sensors, 9 and more. The theoretical background for the nanogenerator and nanopiezotronics is based on a voltage drop created across the cross section of the NW when it is laterally deflected, with the tensile side surface in positive voltage and compressive side in negative voltage. 1,5 It is essential to quantitatively calculate and even develop analytical equations that can give a direct calculation of the voltage at the two side surfaces of the NW, which is important to calculating the efficiency of the nanogenerator and the operation voltage of the nanopiezotronics. In the literature, numerous theories for onedimensional (1D) nanostructure piezoelectricity have been proposed, including first-principles calculations, 10,11 molecular dynamics (MD) simulations, 12 and continuum models. 13
551 citations
TL;DR: In this article, the authors compared the performance of reactive power control and intelligent distributed voltage control in terms of the potential for connecting increased capacities within existing networks. And they showed that the results obtained by the reactive control gave similar results to those obtained by centralized management in the case of the DG.
Abstract: With the rapid increase in distributed generation (DG), the issue of voltage regulation in the distribution network becomes more significant, and centralized voltage control (or active network management) is one of the proposed methods. Alternative work on intelligent distributed voltage and reactive power control of DG has also demonstrated benefits in terms of the minimization of voltage variation and violations as well as the ability to connect larger generators to the distribution network. This paper uses optimal power flow to compare the two methods and shows that intelligent distributed voltage and reactive power control of the DG gives similar results to those obtained by centralized management in terms of the potential for connecting increased capacities within existing networks
549 citations
TL;DR: In this article, the Hessian of the free energy function ceases to be positive definite, which may cause the elastomer to thin down drastically, resulting in an electrical breakdown.
Abstract: Subject to an electric voltage, a layer of a dielectric elastomer reduces its thickness, so that the voltage induces a high electric field. The positive feedback may cause the elastomer to thin down drastically, resulting in an electrical breakdown. The authors show that the electromechanical instability occurs when the Hessian of the free-energy function ceases to be positive definite. Their calculation shows that the stability of the actuator is markedly enhanced by prestresses, agreeing with existing experimental observations.
444 citations
TL;DR: In this paper, the pull-in instability in microelectromechanical (MEMS) resonators was studied and the authors proposed a low-voltage MEMS RF switch actuated with a combined DC and AC loading, which uses a voltage much lower than the traditionally used DC voltage.
Abstract: We study the pull-in instability in microelectromechanical (MEMS) resonators and find that characteristics of the pull-in phenomenon in the presence of AC loads differ from those under purely DC loads. We analyze this phenomenon, dubbed dynamic pull-in, and formulate safety criteria for the design of MEMS resonant sensors and filters excited near one of their natural frequencies. We also utilize this phenomenon to design a low-voltage MEMS RF switch actuated with a combined DC and AC loading. The new switch uses a voltage much lower than the traditionally used DC voltage. Either the frequency or the amplitude of the AC loading can be adjusted to reduce the driving voltage and switching time. The new actuation method has the potential of solving the problem of high driving voltages of RF MEMS switches.
421 citations
TL;DR: The proposed model determines the SOC by incorporating the changes occurring due to terminal voltage, current load, and internal resistance, which mitigate the disadvantages of using impedance only.
Abstract: State-of-charge (SOC) determination is an increasingly important issue in battery technology. In addition to the immediate display of the remaining battery capacity to the user, precise knowledge of SOC exerts additional control over the charging/discharging process, which can be employed to increase battery life. This reduces the risk of overvoltage and gassing, which degrade the chemical composition of the electrolyte and plates. The proposed model in this paper determines the SOC by incorporating the changes occurring due to terminal voltage, current load, and internal resistance, which mitigate the disadvantages of using impedance only. Electromotive force (EMF) voltage is predicted while the battery is under load conditions; from the estimated EMF voltage, the SOC is then determined. The method divides the battery voltage curve into two regions: 1) the linear region for full to partial SOC and 2) the hyperbolic region from partial to low SOC. Algorithms are developed to correspond to the different characteristic changes occurring within each region. In the hyperbolic region, the rate of change in impedance and terminal voltage is greater than that in the linear region. The magnitude of current discharge causes varying rates of change to the terminal voltage and impedance. Experimental tests and results are presented to validate the new models.
414 citations
TL;DR: In this article, a simple electrical model has been established to describe supercapacitor behavior as a function of frequency, voltage and temperature for hybrid vehicle applications, which was derived from experimental data using electrochemical impedance spectroscopy (EIS).
383 citations
TL;DR: The closed-loop control methodology is utilized in the proposed scheme to overcome the voltage drift problem of the power source under the variation of loads and achieve the aim of high-efficiency power conversion.
Abstract: In this paper, a high-efficiency dc-dc converter with high voltage gain and reduced switch stress is proposed. Generally speaking, the utilization of a coupled inductor is useful for raising the step-up ratio of the conventional boost converter. However, the switch surge voltage may be caused by the leakage inductor so that it will result in the requirement of high-voltage-rated devices. In the proposed topology, a three-winding coupled inductor is used for providing a high voltage gain without extreme switch duty-cycle and enhancing the utility rate of magnetic core. Moreover, the energy in the leakage inductor is released directly to the output terminal for avoiding the phenomenon of circulating current and the production of switch surge voltage. In addition, the delay time formed with the cross of primary and secondary currents of the coupled inductor is manipulated to alleviate the reverse-recovery current of the output diode. It can achieve the aim of high-efficiency power conversion. Furthermore, the closed-loop control methodology is utilized in the proposed scheme to overcome the voltage drift problem of the power source under the variation of loads. Some experimental results via an example of a proton exchange membrane fuel cell power source with 250-W nominal rating are given to demonstrate the effectiveness of the proposed power conversion strategy
TL;DR: In this paper, the authors provide an overview of the physics and design of single dielectric barrier discharge (SDBD) plasma actuators for enhanced aerodynamics in a variety of applications.
TL;DR: The causes of charge reversal and the impact of prolonged reversal on power generation using a two air-cathode MFCs stack were investigated and the reason for the voltage reversal was shown to be fuel starvation, resulting in a loss of bacterial activity.
Patent•
30 Aug 2007TL;DR: In this article, a light emitting device (1) turns on a light-emitting unit (7), causes a pulse generation circuit (2), a divider circuit (3), and a count memory circuit (4) to count a continuous electrical connection time, causes the light emitting devices (7) to blink by an ON/OFF patter based on the counting result.
Abstract: When a power voltage is supplied, a light emitting device (1) turns on a light emitting unit (7), causes a pulse generation circuit (2), a divider circuit (3), and a count memory circuit (4) to count a continuous electrical connection time, causes the light emitting device (7) to blink by an ON/OFF patter based on the counting result, and transmits the continuous electrical connection time information outside.
Abstract: The low-voltage ride-through capability of a 2 MW full converter wind turbine with permanent magnet synchronous generator is investigated herein. A detailed description of the system, its controller options and its behaviour when subjected to a severe voltage dip, is presented. A control scheme for the turbine that allows it to withstand severe voltage dips is designed and simulated. This control scheme emphasises the regulation of the dc-link voltage and minimisation of the drive train torque surplus. Also, the level of modelling detail required for stability analysis is analysed and discussed.
TL;DR: In this paper, the basic mechanisms responsible for the electrohydrodynamic (EHD) force exerted by the discharge on the gas molecules were discussed and a parametric study of the EHD force as a function of voltage rise time and dielectric thickness was presented.
Abstract: Surface dielectric barrier discharges (DBDs) have been proposed as actuators for flow control. In this paper we discuss the basic mechanisms responsible for the electrohydrodynamic (EHD) force exerted by the discharge on the gas molecules. A two-dimensional fluid model of the DBD is used to describe the plasma dynamics, to understand the basic physics associated with the EHD force and to give some quantitative estimation of the force under simplified conditions. The results show that for ramp or sinusoidal voltage waveforms, the discharge consists of large amplitude short current pulses during which a filamentary plasma spreads along the surface, separated in time by long duration, low current discharge phases of a Townsend or corona type. The contribution of the low current phases to the total force exerted by the discharge on the gas is dominant because their duration is much longer than that of the current pulses and because the force takes place in a much larger volume. A description of the different discharge regimes and a parametric study of the EHD force as a function of voltage rise time and dielectric thickness is presented.
Patent•
13 Aug 2007
TL;DR: In this article, the average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch, and the regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of a power converter.
Abstract: A system drives one or plurality of LEDs regulating their brightness by controlling LEDs average current or voltage. The system includes a switching power converter and an integrated digital regulator with at least one of electrical, thermal and optical feedbacks. The regulator is constructed as a hysteretic peak current mode controller for continuous mode of operation of the power converter. For discontinuous mode of operation of the power converter a pulse averaging sliding mode control is being used. Average LED current is measured by integrating LED pulse current at off time and hysteretically adjusting on time of the power switch. Input battery is protected from discharging at abnormally low impedance of the output.
TL;DR: A superposition method is proposed to optimize the performance of multiple-output rectifiers and Constant-power scaling and area-efficient design are discussed.
Abstract: Design strategy and efficiency optimization of ultrahigh-frequency (UHF) micro-power rectifiers using diode-connected MOS transistors with very low threshold voltage is presented. The analysis takes into account the conduction angle, leakage current, and body effect in deriving the output voltage. Appropriate approximations allow analytical expressions for the output voltage, power consumption, and efficiency to be derived. A design procedure to maximize efficiency is presented. A superposition method is proposed to optimize the performance of multiple-output rectifiers. Constant-power scaling and area-efficient design are discussed. Using a 0.18-mum CMOS process with zero-threshold transistors, 900-MHz rectifiers with different conversion ratios were designed, and extensive HSPICE simulations show good agreement with the analysis. A 24-stage triple-output rectifier was designed and fabricated, and measurement results verified the validity of the analysis
TL;DR: It is shown that various types of miniature semiconductor diodes floating in water act as self-propelling particles when powered by an external alternating electric field.
Abstract: Microsensors and micromachines that are capable of self-propulsion through fluids could revolutionize many aspects of technology. Few principles to propel such devices and supply them with energy are known. Here, we show that various types of miniature semiconductor diodes floating in water act as self-propelling particles when powered by an external alternating electric field. The millimetre-sized diodes rectify the voltage induced between their electrodes. The resulting particle-localized electro-osmotic flow propels them in the direction of either the cathode or the anode, depending on their surface charge. These rudimentary self-propelling devices can emit light or respond to light and could be controlled by internal logic. Diodes embedded in the walls of microfluidic channels provide locally distributed pumping or mixing functions powered by a global external field. The combined application of a.c. and d.c. fields in such devices allows decoupling of the velocity of the particles and the liquid and could be used for on-chip separations.
TL;DR: This letter presents an improved backward/ forward sweep algorithm for three-phase load-flow analysis of radial distribution systems and shows that the algorithm is accurate and computationally efficient in comparing with two other commonly used methods.
Abstract: This letter presents an improved backward/ forward sweep algorithm for three-phase load-flow analysis of radial distribution systems. In the backward sweep, Kirchhoff's Current Law and Kirchhoff's Voltage Law are used to calculate the upstream bus voltage of each line or a transformer branch. Then, the linear proportional principle is adopted to find the ratios of the real and imaginary components of the specified voltage to those of the calculated voltage at the substation bus. In the forward sweep, the voltage at each downstream bus is then updated by the real and imaginary components of the calculated bus voltage multiplying with the corresponding ratio. The procedure stops after the mismatch of the calculated and the specified voltages at the substation is less than a convergence tolerance. The proposed algorithm is tested with three IEEE benchmark distribution systems. Results show that the algorithm is accurate and computationally efficient in comparing with two other commonly used methods
TL;DR: This paper compares the expense of power semiconductors and passive components of a two-level, three-level neutral-point-clamped, four-level flying-capacitor, and five-level series-connected H-bridge voltage source converter on the basis of the state-of-the-art 6.7-kV insulated gate bipolar transistors for industrial medium-voltage drives.
Abstract: This paper compares the expense of power semiconductors and passive components of a (2.3 kV, 2.4 MVA) two-level, three-level neutral-point-clamped, three-level flying-capacitor, four-level flying-capacitor, and five-level series-connected H-bridge voltage source converter on the basis of the state-of-the-art 6.5-, 3.3-, 2.5-, and 1.7-kV insulated gate bipolar transistors for industrial medium-voltage drives. The power semiconductor losses, the loss distribution, the installed switch power, the design of flying capacitors, and the components of an sine filter for retrofit applications are considered.
TL;DR: In this paper, a modified 3-diode equivalent circuit model for analysis of multicrystalline silicon (Mc-Si) solar cells was proposed to precisely evaluate the characteristics of Mc-Si solar cells taking the influence of grain boundaries and large leakage current through the peripheries into consideration and extract electrical properties.
TL;DR: In this paper, an analytical approach based on Euler-Bernoulli beam theory and Timoshenko beam equations for the voltage and power generation of a PZT bender is presented.
Abstract: Piezoelectric materials (PZT) have shown the ability to convert mechanical forces into an electric field in response to the application of mechanical stresses or vice versa. This property of the materials has found extensive applications in a vast array of areas including sensors and actuators. The study presented in this paper targets the modeling of a PZT bender for voltage and power generation by transforming ambient vibrations into electrical energy. This device can potentially replace the battery that supplies the power in a microwatt range necessary for operating sensors and data transmission. One of the advantages is that it is maintenance-free over a long time span. The feasibility of this application has been repeatedly demonstrated in the literature, but a real demonstration of a working device is partially successful because of the various design parameters necessary for a construction of the PZT bender. According to a literature survey, the device can be modeled using various approaches. This paper focuses on the analytical approach based on Euler–Bernoulli beam theory and Timoshenko beam equations for the voltage and power generation, which is then compared with two previously described models in the literature: the electrical equivalent circuit and energy method. The three models are then implemented in a Matlab/Simulink/Simpower environment and simulated with an AC/DC power conversion circuit. The results of the simulation and the experiment have been compared and discussed.
TL;DR: In this paper, a new conversion structure for the bidirectional interfacing of two dc voltage sources with a higher voltage dc-link is presented, where only three controllable power electronic switches are needed and where the only limit is that the sum of the two dc voltages must be lower or equal than the motor drive dclink voltage.
Abstract: The use of energy storage devices such as batteries or supercapacitors is almost mandatory in fuel cell hybrid electric vehicles, in order to guarantee load leveling, assuring braking energy recovery and good performances in transient operations. To this end, converters with bidirectional power flows are needed to connect the accumulators to the dc-link of the motor drive system. In this paper, a new conversion structure for the bidirectional interfacing of two dc voltage sources with a higher voltage dc-link is presented, where only three controllable power electronic switches are needed and where the only limit is that the sum of the two dc voltages must be lower or equal than the motor drive dc-link voltage. The analysis of the converter structure, the control and modulation systems that have been developed, and simulations and experimental results are reported
10 Sep 2007
TL;DR: In this paper, the authors present a runtime system (CPU MISER) and an integrated performance model for performance-directed, power-aware cluster computing, which supports system-wide, application-independent, fine-grain, dynamic voltage and frequency scaling (DVFS) based power management for a generic poweraware cluster.
Abstract: Performance and power are critical design constraints in today's high-end computing systems. Reducing power consumption without impacting system performance is a challenge for the HPC community. We present a runtime system (CPU MISER) and an integrated performance model for performance-directed, power-aware cluster computing. CPU MISER supports system-wide, application-independent, fine-grain, dynamic voltage and frequency scaling (DVFS) based power management for a generic power-aware cluster. Experimental results show that CPU MISER can achieve as much as 20% energy savings for the NAS parallel benchmarks. In addition to energy savings, CPU MISER is able to constrain performance loss for most applications within user-specified limits. These constraints are achieved through accurate performance modeling and prediction, coupled with advanced control techniques.
Patent•
05 Jan 2007
TL;DR: In this paper, a vehicle propulsion system consisting of an alternating current (AC) traction drive, a first energy storage system, coupled to said traction drive through a direct current (DC) link electrically, and a second ESS system electrically coupled to the output from the second ECS system was presented.
Abstract: A vehicle propulsion system comprising: an alternating current (AC) traction drive; a first energy storage system, coupled to said traction drive through a direct current (DC) link electrically; second energy storage system electrically coupled to said traction drive, such that bi-directional boost converter using a voltage from the DC link is coupled to the output from the second energy storage system; and a unidirectional current device that is poled to conduct current from a low voltage to the boost converter said boost converter high voltage side.
18 Jun 2007
TL;DR: Temperature, voltage, and current sensors monitor the operation of a TCP/IP offload accelerator engine fabricated in 90nm CMOS, and a control unit dynamically changes frequency, Voltage, and body bias for optimum performance and energy efficiency.
Abstract: Temperature, voltage, and current sensors monitor the operation of a TCP/IP offload accelerator engine fabricated in 90nm CMOS, and a control unit dynamically changes frequency, voltage, and body bias for optimum performance and energy efficiency. Fast response to droops and temperature changes is enabled by a multi-PLL clocking unit and on-chip body bias. Adaptive techniques are also used to compensate performance degradation due to device aging, reducing the aging guardband.
TL;DR: A novel dielectrophoresis switching with vertical electrodes in the sidewall of microchannels for multiplexed switching of objects has been designed and tested and can be integrated with other particle detection components to enable microfluidic flow cytometry systems.
Abstract: A novel dielectrophoresis switching with vertical electrodes in the sidewall of microchannels for multiplexed switching of objects has been designed, fabricated and tested. With appropriate electrode design, lateral DEP force can be generated so that one can dynamically position particulates along the width of the channel. A set of interdigitated electrodes in the sidewall of the microchannels is used for the generation of non-uniform electrical fields to generate negative DEP forces that repel beads/cells from the sidewalls. A countering DEP force is generated from another set of electrodes patterned on the opposing sidewall. These lateral negative DEP forces can be adjusted by the voltage and frequency applied. By manipulating the coupled DEP forces, the particles flowing through the microchannel can be positioned at different equilibrium points along the width direction and continue to flow into different outlet channels. Experimental results for switching biological cells and polystyrene microbeads to multiple outlets (up to 5) have been achieved. This novel particle switching technique can be integrated with other particle detection components to enable microfluidic flow cytometry systems.
Patent•
27 Apr 2007
TL;DR: In this article, a method of wirelessly sharing power by inductive inductive method is presented and an apparatus consisting of a first battery (130, 131, 132, 133, 134, 136, 136) supplying power; a rectifier (120, 121, 122, 123, 124, 126) supplied with an AC voltage, converting the AC voltage into a DC voltage, and outputting the DC voltage; an inverter supplied with the dc voltage, converted the dc voltages into the AC voltages, and outputs the DC voltages; and a power control/
Abstract: An apparatus (100, 101, 102, 103, 104, 106) and method of wirelessly sharing power by an inductive method are provided. The apparatus includes a first battery (130, 131, 132, 133, 134, 136) supplying power; a rectifier (120, 121, 122, 123, 124, 126) supplied with an AC voltage, converts the AC voltage into a DC voltage, and outputs the DC voltage; an inverter supplied with the DC voltage, converts the DC voltage into the AC voltage, and outputs the AC voltage; a power control/conversion unit (110, 111, 112, 113, 114, 116) connected to the rectifier or the inverter and supplying power to charge the first battery or a second battery that is provided in an external device as a power supply for the first battery; and a communication unit (170, 171, 172, 173, 174, 176) communicating with the external device.
TL;DR: In this article, an interleaved current-fed full bridge (ICFFB) dc-dc converter is proposed that has low input current ripple to meet the fuel cell demands, by interleaving two isolated CFFB converters with parallel input and series output connection.
Abstract: An interleaved current-fed full bridge (ICFFB) dc-dc converter is proposed in this paper that has low input current ripple to meet the fuel cell demands. By interleaving two isolated CFFB converters with parallel input and series output connection, both input current ripple and output voltage ripple can be reduced. In addition, the size of the magnetic components and current stress of the semiconductor devices on the input side are also reduced. Similarly, smaller voltage rating components can be used on the output side. Only one digital signal processor microcontroller is used to generate phase-shifted gate signals and to implement a cascaded digital control system. The main features of the proposed converter are high efficiency, small passive component size, and small input current ripple. Experimental results for a 1.2-kW interleaved CFFB converter are provided in the paper