Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Language
      Language
      Clear All
      Language
  • Subject
      Subject
      Clear All
      Subject
  • Item Type
      Item Type
      Clear All
      Item Type
  • Discipline
      Discipline
      Clear All
      Discipline
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
5,526 result(s) for "DC/DC converter"
Sort by:
Efficiency Enhancement of Non-Isolated DC-DC Interleaved Buck Converter for Renewable Energy Sources
The article describes the principles based on which it is possible to obtain energy from renewable sources more efficiently. The principles use the conventional DC-DC interleaved buck converter based on the common electronic component types and the control strategy. A novelty of such a proposed solution lies in the methods which are not new, but with the right combination, better results can be achieved. The resulting method can be implemented into various topologies where the highest efficiency for wide input power is required. In case of the renewable energy sources where the power can vary hugely during the day, the proposed method can be implemented. Therefore, the article provides several steps, from calculation through simulation to experimental results that brings reader close to understanding of a such proposed solution.
A Common-Ground Bidirectional Hybrid Switched-Capacitor DC–DC Converter with a High Voltage Conversion Ratio
Electrical energy conversion and storage in DC systems, with increasing importance in industry, requires DC–DC power electronic converters with performances adapted to today’s requirements. In recent years, the applications of DC–DC converters have expanded, including energy storage management strategies, due to the use of supercapacitors for energy storage instead of—or together with—rechargeable batteries, in order to improve overall performance. This article presents a non-isolated, common-ground, bidirectional hybrid switched-capacitor DC–DC converter, which can be efficiently used for supercapacitor charging/discharging, due to its high voltage conversion ratio. The hybrid converter was obtained from the conventional bidirectional buck topology, inserting an “active” switched-capacitor cell. In addition to the high voltage conversion ratio, the switched-capacitor cell brings another important advantage: decreasing the values of all passive components without interrupting the input to the output ground path. All of these positive features were revealed through theoretical analysis and confirmed through digital simulations and experiments, proving that the hybrid converter performs well in both operating modes, with a smooth transition between them.
Modular Isolated DC-DC Converters for Ultra-Fast EV Chargers: A Generalized Modeling and Control Approach
Electric Vehicles (EVs) play a significant role in the reduction of CO2 emissions and other health-threatening air pollutants Accordingly, several research studies are introduced owing to replacing conventional gasoline-powered vehicles with battery-powered EVs. However, the ultra-fast charging (UFC) of the battery pack or the rapid recharging of the battery requires specific demands, including both: the EV battery and the influence on the power grid. In this regard, advanced power electronics technologies are emerging significantly to replace the currently existing gas station infrastructures with the EV charging stations to move from conventional charging (range of hours) to UFC (range of minutes). Among these power electronics conversion systems, the DC-DC conversion stage plays an essential role in supplying energy to the EV via charging the EV’s battery. Accordingly, this paper aims to present possible architectures of connecting multiple Dual Active Bridge (DAB) units as the DC-DC stage of the EV fast charger and study their Small-Signal Modeling (SSM) and their control scheme. These are, namely, Input-Series Output-Series (ISOS), Input-Series Output-Parallel (ISOP), Input-Parallel Output-Parallel (IPOP), and Input-Parallel Output-Series (IPOS). The control scheme for each system is studied through controlling the output filter inductor current such that the current profile is based on Reflex Charging (RC). The main contribution of this paper can be highlighted in providing generalized SSM as well as providing a generalized control approach for the Input-Series Input-Parallel Output-Series Output-Parallel (ISIP-OSOP) connection. The generalized model is verified with three different architectures. The control strategy for each architecture is studied to ensure equal power sharing, where simulation results are provided to elucidate the presented concept considering a three-module ISOS, IPOP, ISOP, and IPOS DC-DC converters.
Non-Isolated Interleaved Hybrid Boost Converter for Renewable Energy Applications
DC-DC boost converters are necessary to extract power from solar panels. The output voltage from these panels is far lower than the utility voltage levels. One of the main functions of the boost converter is to provide a considerable step-up gain to interface the panel to the utility lines. There are several techniques used to boost the low panel voltage. Some of the issues faced by these topologies are a high duty ratio operation, complex design with multiple active switches and discontinuous input current that affects the power drawn from the panel. This paper presents a boost converter topology that combines the advantages of an interleaved structure, a voltage lift capacitor and a passive voltage multiplier network. A mathematical analysis of the proposed converter during its various modes of operation is presented. A 100 W prototype of the proposed converter is designed and tested. The prototype is controlled by a PIC16F18455 microcontroller. The converter is capable of achieving a gain of 10 without operating at extremely high duty ratios. The voltage stress of the switch is far lower than the maximum output voltage.
Capacitance‐sharing, dual‐output, compact, switched‐capacitor DC–DC converter for low‐power biomedical implants
A dual‐output, compact, switched‐capacitor DC–DC converter is presented for efficient voltage generation in low‐power biomedical implants. By sharing the charge transfer capacitors between multiple independent switched‐capacitor DC–DC converters, fewer capacitors are required, resulting in overall system size reduction. A proof‐of‐concept capacitance‐sharing, dual‐output DC–DC converter, converting 1.2 V – 0.4 V and 0.8 V, fabricated in a 0.13 μm CMOS technology, occupying 0.3 mm2 and achieving a peak efficiency of 97.6% is demonstrated.
Analysis of Unidirectional Secondary Resonant Single Active Bridge DC–DC Converter
A compact and highly efficient unidirectional DC–DC converter is required as a battery charger for electrical vehicles, which will rapidly become widespread in the near future. The single active bridge (SAB) converter is proposed as a simple and high-frequency isolated unidirectional converter, which is comprised of an active H-bridge converter in the primary side, an isolated high frequency transformer, and a rectifying secondary diode bridge output circuit. This paper presents a novel, unidirectional, high-frequency isolated DC–DC converter called a Secondary Resonant Single Active Bridge (SR–SAB) DC–DC converter. The circuit topology of the SR–SAB converter is a resonant capacitor connected to each diode in parallel in order to construct the series resonant circuit in the secondary circuit. As a result, the SR–SAB converter achieves a higher total power factor at the high frequency transformer and a unity voltage conversion ratio under the unity transformer turns ratio. Small and nonsignificant overshoot values of current and voltage waveforms are observed. Soft-switching commutations of the primary H-bridge circuit and the soft recovery of secondary diode bridge are achieved. The operating philosophy and design method of the proposed converter are presented. Output power control using transformer frequency variation is proposed. The effectiveness of the SR–SAB converter was verified by experiments using a 1 kW, 48 VDC, and 20 kHz laboratory prototype.
Encapsulated 3Ø converter for power loss minimization in a grid-connected system
A newly designed DC-AC three phase bidirectional converter (DATBC) with an encapsulated DC-DC converter (EDC) for the energy storage system (ESD) is analysed and investigated in this research paper. By using encapsulated or embedded or hidden DC-DC converter a stable and constant DC bus is developed between the encapsulated DC-DC converter and DC-AC three phase bidirectional converter. The proposed converter is entirely different from the traditional dual-stage DC-AC converter, because it takes less than 20% of power used for the DC-AC conversion process. So, this reduced power consumption increases efficiency to a considerable value. A new control technique for zero sequence has been adopted components are inserted in the modulating signal based on carrier pulse width modulation (CPWM). Working principle, implementation and characteristics of the DC-AC three phase bidirectional converter are analysed. Effectiveness and feasibility of the developed converter are examined with a proto-type model.
DC-DC Converter Topologies for Electric Vehicles, Plug-in Hybrid Electric Vehicles and Fast Charging Stations: State of the Art and Future Trends
This article reviews the design and evaluation of different DC-DC converter topologies for Battery Electric Vehicles (BEVs) and Plug-in Hybrid Electric Vehicles (PHEVs). The design and evaluation of these converter topologies are presented, analyzed and compared in terms of output power, component count, switching frequency, electromagnetic interference (EMI), losses, effectiveness, reliability and cost. This paper also evaluates the architecture, merits and demerits of converter topologies (AC-DC and DC-DC) for Fast Charging Stations (FCHARs). On the basis of this analysis, it has found that the Multidevice Interleaved DC-DC Bidirectional Converter (MDIBC) is the most suitable topology for high-power BEVs and PHEVs (> 10kW), thanks to its low input current ripples, low output voltage ripples, low electromagnetic interference, bidirectionality, high efficiency and high reliability. In contrast, for low-power electric vehicles (<10 kW), it is tough to recommend a single candidate that is the best in all possible aspects. However, the Sinusoidal Amplitude Converter, the Z-Source DC-DC converter and the boost DC-DC converter with resonant circuit are more suitable for low-power BEVs and PHEVs because of their soft switching, noise-free operation, low switching loss and high efficiency. Finally, this paper explores the opportunity of using wide band gap semiconductors (WBGSs) in DC-DC converters for BEVs, PHEVs and converters for FCHARs. Specifically, the future roadmap of research for WBGSs, modeling of emerging topologies and design techniques of the control system for BEV and PHEV powertrains are also presented in detail, which will certainly help researchers and solution engineers of automotive industries to select the suitable converter topology to achieve the growth of projected power density.
Solar power based positive output super-lift Luo converter using fuzzy logic controller
Photovoltaic (PV) power generation is employed to meet the increasing demand for energy and of cleaner form. Though renewable and high energy using PV can be produced, they have certain disadvantages. PV cells have a low voltage (approx. 0.5V) rating and they have to be connected in series when higher voltage is required. These cells when connected in series should have identical electrical characteristics to avoid ripples in the output voltage and current, but it is not possible practically. To avoid this miss-match, converter circuits are employed. The major drawbacks in most power converters are reduced voltage gain and their tendency to generate harmonics in the supply system and the load circuit. To overcome these limitations, a positive output super-lift Luo converter is designed. A Positive Output Super Lift Luo converter (POSLC) is a powerful DC-DC converter where the voltage is converted from positive source voltage to positive load voltage as it produces positive voltages of comparatively higher ranges than those of conventional types. The super-lift technique also overcomes the effect of parasitic elements and thus minimizing the ripples in the output voltage and current. In addition to this, the voltage build-up can be achieved by implementing the super-lift technique where the output voltage rises in geometric progression with increased voltage transfer gain and high power density. In this paper fuzzy control is used to produce better-controlled voltage and a more refined output. The performance of POSLC with and without implementation of fuzzy control has been successfully simulated and verified using MATLAB/SIMULINK as well simulation model also developed and analyzed with Proteus package.
An Analysis-Supported Design of a Single Active Bridge (SAB) Converter
Currently, due to its various applications, the high-performance isolated dc-dc converter is in demand. In applications where unidirectional power transfer is required, the single active bridge (SAB) is the most suitable one due to its simplicity and ease of control. The general schematic of the SAB converter consists of an active bridge and a passive bridge, which are connected through a high-frequency transformer thus isolated. The paper summarizes the behavior of this converter in its three operation modes, namely the continuous, discontinuous, and boundary modes. Later, the features of this converter, such as its input-to-output and external characteristics are discussed. Input-to-output characteristics include the variation of converter output power, voltage, and current with an input control variable i.e., phase-shift angle, whereas the external characteristic is the variation of the output voltage as a function of output current. In this discussion, the behavior of this converter in its extreme operating conditions is also examined. The features of the characteristics are elucidated with the help of suitable plots obtained in the MATLAB environment. Afterward, the specifications of a SAB converter are given and, based on the results of the analysis, a detailed design of its electrical elements is carried out. To validate the features and the design procedures presented in this paper, a prototype is developed. An element-wise loss estimation is also carried out and the efficiency of the converter has been found to be approximately equal to 93%. Lastly, the test was executed on this prototype, confirming the theoretical findings concerning this converter.