Online ISSN
1755-4543
Print ISSN
1755-4535
IET Power Electronics
Volume 5, Issue 1, January 2012
Volumes & issues:
Volume 5, Issue 1
January 2012
-
- Author(s): M.A. Chaudhari ; H.M. Suryawanshi ; M.M. Renge
- Source: IET Power Electronics, Volume 5, Issue 1, p. 1 –10
- DOI: 10.1049/iet-pel.2011.0029
- Type: Article
- + Show details - Hide details
-
p.
1
–10
(10)
This study presents the bidirectional controlled switch-based high-frequency (HF) current injection circuit with simple gate control scheme. Improved power factor and total harmonic distortion (THD) of ac input line current of front-end rectifier for ac motor drive is achieved using this scheme. The gating pulses for feedback bidirectional controlled switches are generated at every zero-crossing instances of the respective phase voltages for the duration of π/6 rad. The analysis of the converter along with loss calculations is presented. In order to validate the concept, a prototype model of a converter for 5 kW power using voltage source converter feeding three-phase induction motor is designed in the laboratory. The sinusoidal pulse width modulation switching signals are generated by using DSP (TMS320F2812). The computer simulation results and experimental results are also presented. It is observed that HF current injection for the duration of one-third of phase voltage period results in a remarkable improvement in input current THD and power factor of the front-end rectifier. - Author(s): Y.-P. Hsieh ; J.-F. Chen ; T.-J. Liang ; L.-S. Yang
- Source: IET Power Electronics, Volume 5, Issue 1, p. 11 –21
- DOI: 10.1049/iet-pel.2010.0279
- Type: Article
- + Show details - Hide details
-
p.
11
–21
(11)
A novel high step-up DC–DC converter, which is composed of one boost converter, two capacitors, two diodes and one coupled inductor, is presented in this study. The concept is that the two capacitors are charged in parallel and are discharged in series via the coupled inductor to achieve high step-up voltage gain under appropriate duty ratio. Also, the leakage-inductor energy of the coupled inductor is recycled and the voltage stress on the main switch can be reduced. Besides, the energy of leakage inductor can transfer to capacitor to increase voltage gain. Therefore low conduction resistance RDS(ON) of the main switch can be adopted to reduce the conduction loss. In addition, the reverse-recovery problem of the output diode is alleviated. Thus, the efficiency can be further improved. The operating principle and steady-state analysis are discussed in detail. Finally, a prototype circuit with input voltage 24 V, output voltage 400 V and output power 200 W is implemented in the laboratory to verify the performance of the proposed converter. - Author(s): G.S. Konstantinou ; M.S.A. Dahidah ; V.G. Agelidis
- Source: IET Power Electronics, Volume 5, Issue 1, p. 22 –30
- DOI: 10.1049/iet-pel.2010.0220
- Type: Article
- + Show details - Hide details
-
p.
22
–30
(9)
A detailed analysis of a seven-level selective harmonic elimination pulse-width modulation method suitable for multilevel DC–AC converters is presented in this study. Solution trajectories that cover the normal range of modulation indices typical for the operation of multilevel inverters are documented. The properties and characteristics of these solutions with regard to the distribution of switching instants (angles) to the levels of the waveform are also reported. Selected simulation and experimental results are included for both steady state operation and under dynamic changes of the modulation index and the output frequency. The results confirm the effectiveness of the method. - Author(s): K.G. Pavlou ; M. Vasiladiotis ; S.N. Manias
- Source: IET Power Electronics, Volume 5, Issue 1, p. 31 –40
- DOI: 10.1049/iet-pel.2010.0253
- Type: Article
- + Show details - Hide details
-
p.
31
–40
(10)
This study presents a new approach to the control problem of single-phase switch-mode rectifiers. The proposed approach is based on a particular model predictive control scheme, incorporated with soft constraints for the errors of the key control targets. This control system is free of portional integral (PI) controllers, which are responsible for poor dynamic performance. Control objectives of sinusoidal input current, approximately unity input power factor, and output voltage regulation are successfully met under both steady state and load or setpoint changes. Considering the significant advantages of multilevel operation, the reflected AC side voltage exhibits an appropriate three-level modulation. The developed control strategy involves improved performance compared with a model-based sliding mode one. The theoretical analysis is validated by measurements on a laboratory prototype, illustrating the feasibility and suitability of the proposed controller for this type of rectifiers. - Author(s): P. Lefranc ; X. Jannot ; P. Dessante
- Source: IET Power Electronics, Volume 5, Issue 1, p. 41 –52
- DOI: 10.1049/iet-pel.2010.0284
- Type: Article
- + Show details - Hide details
-
p.
41
–52
(12)
In this article, the authors study the pre-sizing approach of DC–DC buck converters useful for electronics and system designers. The pre-sizing step in an indutrial process is suitable to obtain a preliminary precise sizing of a sub-system (here a buck DC–DC converter): it permits the system designer to perform a feasibility analysis of an overall system (e.g. that contains a buck DC–DC converter). First, static modelling of power devices is proposed: MOSFET, diode, inductor and heatsink. According to an industrial context, the MOSFETs, diodes and heatsinks fitting curves are issued from the manufacturer's datasheets. Second, the objective functions are explained in the case of mixed integer programming problems. Then, the optimisation variables and constraints are highlighted. Third, a section describes the choice of a multi-objective optimisation technique that leads to genetic algorithms (GAs). Fourth, the optimisation results are given. The choice of a final solution of the pre-sizing approach is discussed, considering additional constraints such as diode and MOSFET junctions temperatures, switching frequency etc. The authors focus on the general aspect of the optimisation method proposed here. It can also be used by power electronics designers with the help of additional constraints in accordance to their specific applications. - Author(s): A.G. Abo-Khalil
- Source: IET Power Electronics, Volume 5, Issue 1, p. 53 –58
- DOI: 10.1049/iet-pel.2010.0310
- Type: Article
- + Show details - Hide details
-
p.
53
–58
(6)
A novel online capacitance estimation method for a DC-link capacitor in a three-phase back-to-back pulse width modulation (PWM) converter is proposed. A controlled AC current with a frequency lower than the line frequency is injected into the input side, which then causes AC voltage ripples at the DC output side. With this AC voltage component extracted by band-pass filters, the capacitance is estimated by the support vector regression method without measuring the DC-link current. A function that defines the relation between a given capacitor power and its corresponding capacitance is determined using a set of training data. This function is then used to predict the output for the given input which is not included in the training set. The proposed method can simply be implemented with only software and no additional hardware. Experimental results confirm that the estimation error is less than 0.146%. - Author(s): K.I. Hwu and W.C. Tu
- Source: IET Power Electronics, Volume 5, Issue 1, p. 59 –67
- DOI: 10.1049/iet-pel.2011.0035
- Type: Article
- + Show details - Hide details
-
p.
59
–67
(9)
A novel dimmable light-emitting diode (LED) driver is presented. Via a simple concept, the total harmonic distortion and the power factor of the proposed LED driver are significantly improved as compared to the traditional LED drivers. Above all, there are no capacitor and no inductor in the main power stage of the proposed LED driver, thereby causing the life of the LED driver to be enhanced and the integral circuit design to be easy to achieve. Moreover, a new LED dimming strategy is presented. The basic operating principles of the LED driver are described in detail, along with some simulated and experimental results to demonstrate the effectiveness and feasibility of the proposed LED driver. - Author(s): C.Y. Chan
- Source: IET Power Electronics, Volume 5, Issue 1, p. 68 –73
- DOI: 10.1049/iet-pel.2011.0077
- Type: Article
- + Show details - Hide details
-
p.
68
–73
(6)
The development of non-linear controllers for a tri-state boost converter in the presence of an unknown load is addressed. In contrast to the conventional boost converter, the tri-state boost converter has two control inputs and does not have a right-half-plane zero. The controllers are designed using the average model of the tri-state boost converter to vary both the ‘boost’ and ‘capacitor-charging’ intervals using the average model of the tri-state boost converter to achieve fast response and a small inductor current. Experimental results to illustrate the features of the controllers are provided. - Author(s): K. Ding ; K.W.E. Cheng ; Y.P. Zou
- Source: IET Power Electronics, Volume 5, Issue 1, p. 74 –85
- DOI: 10.1049/iet-pel.2010.0370
- Type: Article
- + Show details - Hide details
-
p.
74
–85
(12)
Traditional means for implementing the switching of the power switches in multilevel converters is subharmonic pulse width modulation (SHPWM) or triangulation approach involving a comparison between a target reference waveform and several high-frequency carrier waveforms where all the power switches usually work at high switching frequency. The asymmetric modulation method (AMM) which is derived from hybrid modulation method is illustrated. The contribution of asymmetric modulation is to provide a general method of finding the locus of the output stepped-wave for the hybrid modulation method. This study also provides an illustration of the ‘Mathematic expression of modulation process’ of SHPWM and AMM where it is easy to see how the two techniques are related, and the output expression of the AMM method can be easily obtained from the general N-level double-Fourier output expressions of SHPWM where cumbersome mathematical work has been avoided. Through the analysis of modulation process for SHPWM and AMM, results show that the AMM is an improved version of SHPWM method with optimised switching combination. Theoretical analysis, simulation and experimental results are provided to validate the feasibility of the proposed analysis method. - Author(s): R.-L. Lin ; W.-S. Liu ; J.-F. Chen ; M.-H. Chen ; C.-H. Liu
- Source: IET Power Electronics, Volume 5, Issue 1, p. 86 –94
- DOI: 10.1049/iet-pel.2010.0092
- Type: Article
- + Show details - Hide details
-
p.
86
–94
(9)
Voltage allocation (VA) is analysed for a multi-module power conversion system using a parallel-input and series-output (PISO) connection with different power ratings. In PISO system, the multi-module converters with different power ratings cannot regulate total output voltage when one of the series module is operated in its voltage limited mode. Therefore an automatic master loop regulation (AMLR) control scheme is proposed to allocate output voltage of individual modules, as well as to regulate total output voltage and achieve power management. Presented also is a green-mode control (AMLR+backup module) that could shield backup module in light-load to improve light-load efficiency. Finally, by using green-mode control, the experimental prototypes of three PISO forward modules with different power ratings are implemented in order to achieve VA mechanism. The efficiency of the multi-module PISO system with the proposed control scheme in the light-load is improved by over 12%, as compared to the conventional control scheme. - Author(s): S. Roy and L. Umanand
- Source: IET Power Electronics, Volume 5, Issue 1, p. 95 –105
- DOI: 10.1049/iet-pel.2011.0110
- Type: Article
- + Show details - Hide details
-
p.
95
–105
(11)
Handling unbalanced and non-linear loads in a three-phase AC power supply has always been a difficult issue. This has been addressed in the literature by either using fast controllers in the fundamental rotating reference frame or using separate controllers in reference frames specific to the harmonics. In the former case, the controller needs to be fast and in the latter case, besides the need for many controllers, negative-sequence components need to be extracted from the measured signal. This study proposes a control scheme for harmonic and unbalance compensation of a three-phase uninterruptible power supply wherein the problems mentioned above are addressed. The control takes place in the fundamental positive-sequence reference frame using only a set of feedback and feed-forward compensators. The harmonic components are extracted by a process of frame transformations and used as feed-forward compensation terms in the positive-sequence fundamental reference frame. This study uses a method wherein the measured signal itself is used for fundamental negative-sequence compensation. As the feed-forward compensator handles the high-bandwidth components, the feedback compensator can be a simple low-bandwidth one. This control algorithm is explained and validated experimentally. - Author(s): N. Farokhnia ; S.H. Fathi ; N. Yousefpoor ; M.K. Bakhshizadeh
- Source: IET Power Electronics, Volume 5, Issue 1, p. 106 –114
- DOI: 10.1049/iet-pel.2011.0092
- Type: Article
- + Show details - Hide details
-
p.
106
–114
(9)
Recently, a switching strategy based on minimisation of total harmonic distortion (MTHD) has been proposed. Normally, in multilevel flexible AC transmission systems, DC voltages of capacitors are changed. It is proposed to regulate this value on a predefined value. Thus, desired value is employed for optimising THD value. Results show effectiveness of the proposed method in minimising THD, when it is compared with the case of a multilevel inverter with constant DC sources. Genetic algorithm as a powerful tool is used to minimise THD as well as satisfy fundamental component. To verify theory and simulation results, a seven-level cascaded inverter-based hardware prototype is built. - Author(s): R.-Y. Duan and J.-D. Lee
- Source: IET Power Electronics, Volume 5, Issue 1, p. 115 –123
- DOI: 10.1049/iet-pel.2010.0401
- Type: Article
- + Show details - Hide details
-
p.
115
–123
(9)
This study presents a novel soft-switching bidirectional dc-dc converter with a coupled inductor. Transformer-based circuit topologies are commonly employed in conventional bidirectional converters and soft-switching techniques, including zero-voltage switching (ZVS) or zero-current switching (ZCS), are frequently applied to mitigate switching losses. Unfortunately, the use of more than four switches and several diodes in these transformer-based schemes increase production costs and reduce conversion efficiency. This work presents a coupled-inductor bidirectional converter scheme that utilises four power switches to achieve the goal of bidirectional current control. The high step-up and step-down ratios enable a battery module current with a low-voltage level to be injected into a high-voltage dc bus for subsequent utilisation. Experimental results based on a 24 V/200 V 800 W prototype are provided to verify the effectiveness of the proposed bidirectional converter. Since the voltage clamping, synchronous rectification and soft-switching techniques are utilised in the proposed circuit topology and the corresponding device specifications are adequately fulfilled, the proposed converter can provide highly efficient bidirectional power conversion in a wide range on the low-voltage side. - Author(s): S. De ; M. Rajne ; S. Poosapati ; C. Patel ; K. Gopakumar
- Source: IET Power Electronics, Volume 5, Issue 1, p. 124 –133
- DOI: 10.1049/iet-pel.2010.0329
- Type: Article
- + Show details - Hide details
-
p.
124
–133
(10)
As aircraft technology is moving towards more electric architecture, use of electric motors in aircraft is increasing. Axial flux BLDC motors (brushless DC motors) are becoming popular in aero application because of their ability to meet the demand of light weight, high power density, high efficiency and high reliability. Axial flux BLDC motors, in general, and ironless axial flux BLDC motors, in particular, come with very low inductance Owing to this, they need special care to limit the magnitude of ripple current in motor winding. In most of the new more electric aircraft applications, BLDC motor needs to be driven from 300 or 600 Vdc bus. In such cases, particularly for operation from 600 Vdc bus, insulated-gate bipolar transistor (IGBT)-based inverters are used for BLDC motor drive. IGBT-based inverters have limitation on increasing the switching frequency, and hence they are not very suitable for driving BLDC motors with low winding inductance. In this study, a three-level neutral point clamped (NPC) inverter is proposed to drive axial flux BLDC motors. Operation of a BLDC motor driven from three-level NPC inverter is explained and experimental results are presented. - Author(s): L.C. Meng ; K.W. Eric Cheng ; K.W. Chan ; Y. Lu
- Source: IET Power Electronics, Volume 5, Issue 1, p. 134 –141
- DOI: 10.1049/iet-pel.2010.0388
- Type: Article
- + Show details - Hide details
-
p.
134
–141
(8)
This study aims to enhance heating performance of an induction cooker with convex bottom Chinese wok for commercial applications. Traditional single coil solution is first designed according to the wok shape. The theoretical closed-form expressions of the eddy currents in the wok are derived, and further verified by finite-element method (FEM) analysis. The results reveal the localised and uneven eddy currents distribution for the induction cooker with an evenly distributed single coil. Variable turn pitch (VTP) coils are then proposed to address the eddy currents distribution problem. Corresponding analytical equations are given to present the design process of the VTP coils. The resulting eddy currents distribution on the wok is validated to be improved by applying the VTP coils. The inductance characteristics of the proposed VTP coils are also studied by conducting FEM and physical measurements. Finally, a prototype of the proposed system is developed and has undergone comprehensive experiments. The experimental results validate the theoretical analysis, indicating that the heating performance of the induction cooker system would be remarkably enhanced by implementing the VTP coils. - Author(s): J. Tian ; Q. Chen ; B. Xie
- Source: IET Power Electronics, Volume 5, Issue 1, p. 142 –148
- DOI: 10.1049/iet-pel.2011.0003
- Type: Article
- + Show details - Hide details
-
p.
142
–148
(7)
In order to reduce inverter capacity and enhance system reliability, a novel series hybrid active power filter (APF) based on controllable harmonic impedance is proposed in this study. As the pulse-width-modulated inverter works as a controlled harmonic current source, the series transformer (ST) can exhibit the controllable impedance to harmonic current, which makes the impedance of primary winding of series transformer very high for all frequencies except for the fundamental, thus forcing all harmonic current components through the passive filters and therefore preventing harmonic currents from entering the main power system. Adopting the small self-inductance ST, the inverter and secondary winding of the ST need not endure the fundamental current but only endure the injected harmonic currents, and the LC fundamental tuned bypass can be omitted; so the cost of the proposed APF will be very low. The validity of the proposed APF is verified by the simulation and experimental results.
A three-phase unity power factor front-end rectifier for AC motor drive
Analysis and implementation of a novel single-switch high step-up DC–DC converter
Solution trajectories for selective harmonic elimination pulse-width modulation for seven-level waveforms: analysis and implementation
Constrained model predictive control strategy for single-phase switch-mode rectifiers
Virtual prototyping and pre-sizing methodology for buck DC–DC converters using genetic algorithms
Current injection-based DC-link capacitance estimation using support vector regression
Dimmable driver for light-emitting diode with total harmonic distortion improved
Development of non-linear controllers for a tri-state boost converter
Analysis of an asymmetric modulation method for cascaded multilevel inverters
Voltage allocation control for multi-module power conversion system with parallel-input and series-output connection
Control technique for non-linear and unbalance compensation of an integrated magnetics-based three-phase series-shunt-compensated uninterruptible power supply
Minimisation of total harmonic distortion in a cascaded multilevel inverter by regulating voltages of DC sources
High-efficiency bidirectional DC-DC converter with coupled inductor
Low-inductance axial flux BLDC motor drive for more electric aircraft
Variable turn pitch coils design for heating performance enhancement of commercial induction cooker
Series hybrid active power filter based on controllable harmonic impedance
Most viewed content for this Journal
Article
content/journals/iet-pel
Journal
5
Most cited content for this Journal
-
Review of dc–dc converters for multi-terminal HVDC transmission networks
- Author(s): Grain Philip Adam ; Islam Azmy Gowaid ; Stephen Jon Finney ; Derrick Holliday ; Barry W. Williams
- Type: Article
-
Structure for multi-input multi-output dc–dc boost converter
- Author(s): Ebrahim Babaei and Okhtay Abbasi
- Type: Article
-
Developed embedded switched-Z-source inverter
- Author(s): Ebrahim Babaei ; Elias Shokati Asl ; Mohsen Hasan Babayi ; Sara Laali
- Type: Article
-
Three-phase AC/DC power-flow for balanced/unbalanced microgrids including wind/solar, droop-controlled and electronically-coupled distributed energy resources using radial basis function neural networks
- Author(s): Hamid Reza Baghaee ; Mojtaba Mirsalim ; Gevork B. Gharehpetian ; Heidar Ali Talebi
- Type: Article
-
High-voltage-gain quadratic boost converter with voltage multiplier
- Author(s): Neng Zhang ; Danny Sutanto ; Kashem M. Muttaqi ; Bo Zhang ; Dongyuan Qiu
- Type: Article
