Your browser does not support JavaScript!
http://iet.metastore.ingenta.com
1887
banner image
image of Volume 4, Issue 3
Online ISSN 1755-4543 Print ISSN 1755-4535

IET Power Electronics

Volume 4, Issue 3, March 2011

Volumes & issues:

Volume 4, Issue 3

March 2011

Show / Hide details

    • Technique for simulating the steady-state response of power electronic converters
      • Author(s): S.R. Naidu  and  D.A. Fernandes
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 269 –277
      • DOI:  10.1049/iet-pel.2009.0321
      • Type: Article
      • + Show details - Hide details
      • p. 269 –277 (9)
        A technique for directly simulating the steady-state response of power electronic converters has been proposed. It is based on the representation of circuit elements by impedance or admittance matrices for periodic waveforms. A Newton–Raphson procedure is then used to solve the non-linear circuit equations. Detailed semiconducting device models may be easily included in the computations. The responses of typical power electronic converters have been computed and their waveforms have been presented. The technique is able to simulate non-autonomous and autonomous circuits.
        Add to favourites
        Export citations
      Understanding the operation of a Z-source inverter for photovoltaic application with a design example
      • Author(s): M. Hanif ; M. Basu ; K. Gaughan
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 278 –287
      • DOI:  10.1049/iet-pel.2009.0176
      • Type: Article
      • + Show details - Hide details
      • p. 278 –287 (10)
        Traditional voltage source inverter (VSI) and current source inverter (CSI) technology has advanced to the new Z-source inverter (ZSI) with a built-in impedance network, with modification to the traditional pulse width modulated (PWM) signal. Modified PWM signal accommodates the shoot-through (ST) signal (which would destroy the traditional inverters) in order to buck or boost the DC input voltage from a value between zero and infinity. The unique impedance network of passive elements, which gives a single-stage conversion, needs to be understood in detail in order to design a ZSI. The study compares traditional inverters against the ZSI and discusses the detailed operation modes involved. Circuit calculations, self-boost phenomenon, ST, inductor and capacitor design calculations, boost control methods and device selection procedures are discussed. Photovoltaic source (PV) being one of the most promising DC sources of the future, a design example involving PV and all the circuit calculations along with matching simulation results, are provided in this study.
        Add to favourites
        Export citations
      Zero-current-transition two-switch flyback pulse-width modulated DC–DC converter
      • Author(s): D. Murthy-Bellur  and  M.K. Kazimierczuk
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 288 –295
      • DOI:  10.1049/iet-pel.2009.0253
      • Type: Article
      • + Show details - Hide details
      • p. 288 –295 (8)
        This study presents a zero-current-transition (ZCT) two-switch flyback pulse-width modulated (PWM) DC–DC converter with a simple auxiliary circuit. The auxiliary circuit consists of an active switch and a clamp capacitor. The clamping diodes on the primary side of the two-switch flyback topology clamp the peak voltage across each main switch to the DC input voltage VI. This feature of the two-switch flyback converter is combined with the ZCT feature provided by a simple auxiliary circuit connected on the secondary side of the transformer, which results in a soft-switching two-switch flyback converter. Circuit description, principle of operation, steady-state analysis and design procedure of the ZCT two-switch flyback converter are presented. Simulation and experimental results from a laboratory prototype are given to validate the theoretical analysis.
        Add to favourites
        Export citations
      Neutral point clamped converter for high fundamental frequency applications
      • Author(s): L. D'Errico ; A. Lidozzi ; L. Solero
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 296 –308
      • DOI:  10.1049/iet-pel.2009.0166
      • Type: Article
      • + Show details - Hide details
      • p. 296 –308 (13)
        The proposed study intends to investigate the benefits of using multilevel converters in low-voltage fed applications at high fundamental frequency as high-speed electric drives, with particular reference to the energy recovering from gas exhausts in automotive systems. Comparison of a conventional two-level sine wave converter and a neutral point clamped (NPC) converter has been developed and investigated. Experimental results have been achieved by means of a prototypal realisation of a three-phase three-level NPC converter.
        Add to favourites
        Export citations
      Switched-coupled inductor cell for DC–DC converters with very large conversion ratio
      • Author(s): Y. Berkovich  and  B. Axelrod
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 309 –315
      • DOI:  10.1049/iet-pel.2009.0341
      • Type: Article
      • + Show details - Hide details
      • p. 309 –315 (7)
        By replacing the inductor in basic converters by a coupled-inductor, and adding one diode, new converters with a small count of elements and a high conversion ratio are obtained. The additional diode helps to circulate the leakage inductance energy to the load in a non-oscillatory manner. This diode conducts for a short period of time. The transistor turns on/off with soft-switching. The diodes turn on with zero-voltage switching and turn off with zero-current-switching, their reverse-recovery problem is alleviated. A switching-coupled inductor boost converter is studied in detail, and a family of DC–DC converters (boost, buck-boost, Ćuk, Sepic, Zeta) based on the new switching cell is then presented. The dependence of the voltage gain on the magnetic-coupling coefficient and turns ratio of the coupled inductor is studied. The influence of the load value on the voltage conversion ratio is discussed based on an exact analysis, which avoids assumptions of ideal elements. Computer simulation and experimental results confirmed the theoretical expectations.
        Add to favourites
        Export citations
      High step-up zero-voltage switching current-fed isolated pulse width modulation DC–DC converter
      • Author(s): M. Delshad  and  H. Farzanehfard
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 316 –322
      • DOI:  10.1049/iet-pel.2009.0246
      • Type: Article
      • + Show details - Hide details
      • p. 316 –322 (7)
        This study presents a new zero-voltage switching (ZVS) current-fed isolated pulse width modulation DC–DC converter. In this converter all switches turn on under zero-voltage zero-current switching and turn off under almost ZVS. Furthermore, the voltage spike across the main switch due to leakage inductance of isolating transformer is absorbed. Considering high efficiency and voltage gain of this converter, it is suitable for green generated systems such as fuel cells or photovoltaic systems. The proposed converter operating modes are analysed and theoretical waveforms are shown. The presented experimental results confirm the integrity of the proposed converter.
        Add to favourites
        Export citations
      Power quality enhancement utilising single-phase unified power quality conditioner: digital signal processor-based experimental validation
      • Author(s): V. Khadkikar ; A. Chandra ; A.O. Barry ; T.D. Nguyen
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 323 –331
      • DOI:  10.1049/iet-pel.2010.0031
      • Type: Article
      • + Show details - Hide details
      • p. 323 –331 (9)
        This study is based on a single-phase unified power quality conditioner (UPQC) to enhance power quality problem in single-phase systems. A simple control approach is implemented and validated through simulation as well as experimental studies. A laboratory prototype of UPQC is designed and developed using a digital signal processor. The performance of UPQC is validated experimentally under several operating conditions. It is found that the UPQC in single-phase system effectively compensates the important power quality issues, such as the load reactive power, load current harmonics, voltage harmonics, voltage sag, voltage swell and voltage flicker. Under distorted source voltage having total harmonics distortion (THD) of 14.1% with a non-linear load producing a distorted current (THD of 30.98%), the UPQC simultaneously compensates these harmonics resulting sinusoidal source current (THD of 3.77%) and load voltage (THD of 2.54%).
        Add to favourites
        Export citations
      N-switched-capacitor buck converter: topologies and analysis
      • Author(s): Y. Jiao  and  F.L. Luo
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 332 –341
      • DOI:  10.1049/iet-pel.2010.0104
      • Type: Article
      • + Show details - Hide details
      • p. 332 –341 (10)
        A series of n-switched-capacitor buck converters are proposed in this article. The most important feature is that they can provide even steeper step-down voltage to satisfy some extreme applications where low voltage and high current are required. They have the advantages of smaller sizes and simpler controlling algorithm compared to cascade buck converter and higher efficiency compared to the quadratic converter reported in former literature. This series can be introduced into on-board aeronautics modern power architectures and solar energy storage systems. Theoretical analysis is supported by simulation and experimental results.
        Add to favourites
        Export citations
      Half-wave symmetry selective harmonic elimination method for multilevel voltage source inverters
      • Author(s): W. Fei ; B. Wu ; Y. Huang
      • Source: IET Power Electronics, Volume 4, Issue 3, p. 342 –351
      • DOI:  10.1049/iet-pel.2010.0061
      • Type: Article
      • + Show details - Hide details
      • p. 342 –351 (10)
        This study investigates in detail the properties of multiple solutions of different existing selective harmonic elimination (SHE)-pulse-width modulation (PWM) schemes for multilevel voltage source inverters. In order to obtain more solutions to SHE-PWM problems, a novel half-wave symmetry SHE modulation method and its generalised formulation are proposed. The advantages of the proposed formulation include simplicity in format, flexibility in PWM waveforms and a broad solution space. Taking a five-level inverter with 20 points in half a cycle as an example, 12 groups of solutions at modulation index (M) of 0.8 are obtained and illustrated. A set of solutions for M varying from 0 to 1.15 are also listed in forms of initial values and their effective regions. Simulations on a Psim platform are carried out. An experimental prototype with a five-level cascade voltage source inverter topology is built and investigated. The experimental results agree well with simulated ones, which prove the validity and practicability of the new method.
        Add to favourites
        Export citations

Most viewed content for this Journal

Article
content/journals/iet-pel
Journal
5
Loading

Most cited content for this Journal

Print this page
This is a required field
Please enter a valid email address