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Series space vector modulation for multi-level cascaded H-bridge inverters

IET POWER ELECTRONICS 2010年第6期3卷 843-857页

作者： Rabinovici, R. Baimel, D. Tomasik, J. Zuckerberger, A. Ben Gurion Univ Negev Dept Elect & Comp Engn IL-84105 Beer Sheva Israel ATDD ABB Turgi CH-5300 Turgi Switzerland A2Z Consulting Ltd IL-20142 Misgav Israel

The study presents a series space vector modulation (SVM) method for multi-level cascaded H-bridge inverters. The proposed method s based on construction of multi-level reference voltage vectors from three-level voltage vectors, which are present in the space vector diagram of the multi-level inverter. The proposed approach is compared to the conventional SVM and the carrier-based pulse-width modulation (PWM) ones on 5-, 7-, and 13-level inverters. The implementation of these methods was simulated by Simulink. The simulation results show that implementation of the proposed series SVM is possible. Important advantages of the present series SVM approach against the conventional SVM one are simplicity and easy identification of triangles. Furthermore, it could be easily extended to any n-level inverter.

关键词： series space vector modulation bridge circuits Simulink simulation multilevel reference voltage vectors Power convertors and power supplies to apparatus pulse-width modulation PWM invertors multi-level cascaded H-bridge inverters

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Improved linear model of self oscillating systems such as relay feedback current controllers

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CONTROL ENGINEERING PRACTICE 2010年第8期18卷 927-935页

作者： Olivier, J. -C. Loron, L. Auger, F. Le Claire, J. -C. CRTT IREENA F-44602 St Nazaire France

In this paper, some analytical tools for the study of self-oscillating systems such as current-controlled static converters using pulse-width modulators are presented. These tools, based on the Tsypkin locus, concern the prediction of the switching frequency of the power stage and the characterization of its input-output behavior by an equivalent linear model. These first results, that can be used for any value of the duty cycle, are extended to the construction of the frequency response of the closed-loop system, where the power stage is replaced by a constant gain, associated with a constant time delay. This study is validated by experiments using a classical hysteresis current controller and a recent current controller without hysteresis. The obtained results are particularly useful for applications such as active filtering or high precision power supplies, where the frequency of the signal to follow can be close to one fifth of the switching frequency. (C) 2010 Elsevier Ltd. All rights reserved.

关键词： Continuous-time control Self-oscillation Current regulators pulse-width modulation Feedback linearization Dynamic modeling

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Effect of weak pulse electric fields on surface properties and destructive activity of Pseudomonas bacteria

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COLLOID JOURNAL 2010年第6期72卷 830-836页

作者： Podolska, V. I. Yakubenko, L. N. Ulberg, Z. R. Ermakov, V. N. Grischenko, N. I. Natl Acad Sci Ukraine Ovcharenko Inst Biocolloid Chem UA-03142 Kiev 142 Ukraine Natl Acad Sci Ukraine Bogoliubov Inst Theoret Phys UA-03143 Kiev 143 Ukraine

The effect of weak pulse electric fields on the destructive activity and surface properties of Pseudomonas bacteria is studied. It is revealed that the physiological response of bacteria on their treatment by external pulse fields depends on field parameters and is accompanied by the changes in the values of electrokinetic potential and hydrophobicity. The treatment of bacteria by the electric field with pulse duration of 1-10 ms and frequency of 100-500 Hz tends to increase by 20-30% the destruction of NaAg(CN)(2). It is suggested that changes in surface properties and the enhancement of biochemical activity of bacteria are based on the metabolic reaction of the cell related to the stimulation or suppression of the bacteria respiration upon the imposition of external field.

关键词： ELECTRIC fields PSEUDOMONAS HYDROPHOBIC surfaces ELECTRIC stimulation MICROBIAL respiration ELECTROKINETICS pulse-width modulation

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Linearisation method and control for series active power filter by means of pulse-width modulation

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IEE PROCEEDINGS-ELECTRIC POWER APPLICATIONS 2006年第3期153卷 337-342页

作者： Ramos, A. Nuez, I. Feliu, V. Univ Las Palmas Gran Canaria ETS Ingn Ind Las Palmas Gran Canaria Spain Univ Castilla La Mancha ETS Ingn Ind E-13071 Ciudad Real Spain

The increase of nonlinear loads in networks involves rises in harmonic currents, resulting in voltage distortion that can affect other sensitive loads. The series voltage compensators are the devices used to reduce voltage deformation in networks of nonnegligible impedance. The control technique of the series compensator is one factor which can improve the operation of the series compensator, in order to reduce voltage disturbances existing in the network. The control of devices controlled by PWM permits the use of classical linear strategies and nonlinear control. Initially, in the paper, the linear and discrete model of the voltage compensator is obtained by using an original linearisation method for systems controlled by PWM, which shows better behaviour than conventional methods. Then a control algorithm is developed in minimum time based on the linear model obtained. The control algorithm has been simulated and has subsequently been implemented in a laboratory prototype of the series compensator, giving very satisfactory results.

关键词： pulse-width modulation HARMONICS (Electric waves) CAPACITORS ELECTRIC potential ALGORITHMS VOLTAGE regulators

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PWM Technique to Extend Current Reconstruction Range and Reduce Common-Mode Voltage for Three-Phase Inverter using DC-link Current Sensor Only

PWM Technique to Extend Current Reconstruction Range and Red...

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2011 IEEE Energy Conversion Congress and Exposition (ECCE 2011)

作者： Yong-Kai Lin Yen-Shin Lai Center for Power Electronics Technology National Taipei University of Technology Taipei Taiwan

ISBN: (纸本)9781457705427

A PWM technique for three-phase inverter current reconstruction using only one current sensor is presented. As compared to previous work, the proposed technique not only can extend the current reconstruction range, but also decrease the common mode voltage of inverter output. Moreover, the theoretical analysis for the limitation to current reconstruction using only one current sensor is included in this paper. It will be shown that reduction of PWM switching frequency and acquisition time of AD conversion will extend the current reconstruction range for a given PWM technique. Experimental results derived from an FPGA-based controlled inverter show that using the presented PWM technique the three-phase current signals of inverter can be reconstructed even under very low modulation index range while reducing the common-mode noise of inverter output.

关键词： pulse-width modulation Inverter Common-mode Voltage

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A four-quadrant voltage converter (600 V, 500 A)

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INSTRUMENTS AND EXPERIMENTAL TECHNIQUES 2010年第2期53卷 240-245页

作者： Erokhin, A. I. Medvedko, A. S. Skorobogatov, D. N. Selivanov, P. A. Russian Acad Sci Budker Inst Nucl Phys Siberian Div Novosibirsk 630090 Russia

A power system based on regulators connected in a pulse-width modulation (PWM) half-bridge circuit with up-to-date power IGBT switches. The system ensures the four-quadrant operation with an out-put voltage of up to 600 V and current of up to 500 A. The control system is based on a digital signal processor and ensures all necessary measurements, interlocks, PWM signal generation, and communication with the computer.

关键词： pulse-width modulation SIGNAL processing -- Digital techniques ELECTRONIC circuits ELECTRONICS pulse modulation (Electronics)

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Light-load efficiency increase in high-frequency integrated DC-DC converters by parallel dynamic width controlling

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ANALOG INTEGRATED CIRCUITS AND SIGNAL PROCESSING 2010年第1期62卷 1-8页

作者： Lorentz, V. R. H. Berberich, S. E. Maerz, M. Bauer, A. J. Ryssel, H. Poure, P. Braun, F. Nancy Univ LIEN Vandoeuvre Les Nancy France Fraunhofer IISB Dept Technol Erlangen Germany ULP InESS Strasbourg France Fraunhofer IISB Devices Grp Erlangen Germany Fraunhofer IISB Silicon Carbide SiC Program Erlangen Germany

A significant improvement of the light load conversion efficiency in integrated CMOS DC-DC converters using pulse-width modulation (PWM) at constant switching frequencies above 1 MHz can be obtained by implementing dynamic width controlling (DWC) of the power transistors. The parallel implementation of DWC uses equally sized power cells, each containing the power transistor and its gate driver stages. The power cells are connected together in a parallel arrangement to limit the propagation delays and to avoid the transmission gates used in serial implementations. Due to this, higher switching frequencies can be realized. Advanced simulations were performed with Cadence Spectre combined with Mathematica to investigate the conversion efficiency improvement potential offered by DWC. With DWC, an absolute increase of the light load conversion efficiency as high as 29% can be achieved for switching frequencies in the range 1-10 MHz. Further, a conversion efficiency higher than 80% can be provided over roughly two decades of load current for a DC-DC converter operating at a switching frequency of 10 MHz. Experimental results obtained from a synchronous buck converter designed in a 0.18 mu m CMOS technology and switched at 2 MHz in continuous conduction mode (CCM) have demonstrated an improvement of the light-load conversion efficiency of about 25%.

关键词： Integrated CMOS DC-DC converter Dynamic width controlling Light-load Power conversion efficiency High switching frequency Synchronous rectification pulse-width modulation

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A particle swarm optimisation based technique of harmonic elimination and voltage control in pulse-width modulated inverters

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INTERNATIONAL JOURNAL OF BIO-INSPIRED COMPUTATION 2010年第1期2卷 18-26页

作者： Upendar, J. Singh, G. K. Gupta, C. P. Indian Inst Technol Dept Elect Engn Roorkee Uttarakand India

A particle swarm optimisation (PSO) based method is presented for selective harmonics elimination (SHE) solution in pulse-width modulated (PWM). PSO is used to determine the switching pulses by solving the non-linear equation's formed with the Fourier analysis of the output waveform which enables the control of the fundamental component. The application of the proposed method to single phase and three phase inverter is demonstrated with respect to harmonic distortion by eliminating the unwanted lower harmonic component up to 19th order. The selected performance features are validated by relevant waveforms, which are obtained by simulation of different examples with the use of MATLAB software, which shows the better perform of the proposed method.

关键词： particle swarm optimisation PSO selective harmonic elimination pulse-width modulation PWM inverter

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FPGA-based PWM for three-phase SEPIC rectifier

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IEICE ELECTRONICS EXPRESS 2010年第18期7卷 1335-1341页

作者： Raihan, Siti Rohani S. Rahim, Nasrudin Abd Univ Malaya Ctr Res Power Elect Drives Automat & Control Fac Engn Kuala Lumpur 50603 Malaysia

This paper presents the design and implementation of synchronous pulse-width modulation (PWM) for a three-phase three-switch Single Ended Primary Inductance Converter (SEPIC). The PWM switching patterns are generated from an Altera Cyclone II field programmable gate array (FPGA) device. Two types of carrier waveforms are used with two 60 degrees sine waveforms, taking less space in the FPGA, providing more space for control circuits. Comparative study of two PWM methods is also shown. Verification of simulation results are based on hardware-in-the-loop technique, to show the effectiveness of digital-based PWM control.

关键词： pulse-width modulation FPGA rectifier SEPIC hardware-in-the-loop

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Propagation of elliptically polarized laser pulses in isotropic gyrotropic medium with relaxation cubic nonlinearity and anomalous frequency dispersion

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OPTICS AND SPECTROSCOPY 2010年第5期109卷 778-782页

作者： Makarov, V. A. Perezhogin, I. A. Potravkin, N. N. Moscow MV Lomonosov State Univ Ctr Int Laser Moscow 119991 Russia Moscow MV Lomonosov State Univ Fac Phys Moscow 119991 Russia

The self-action of elliptically polarized Gaussian laser pulses in an isotropic gyrotropic medium with an anomalous frequency dispersion and cubic Kerr nonlinearity with a finite relaxation time on the order of the pulse duration is numerically studied. It is shown that, at the output of the medium, the pulse polarization nonmonotonically varies with time. The main peak of the pulse is additionally delayed compared to the time of passing the linear medium;the value of this delay significantly depends on the polarization of the incident pulse and achieves a maximum for incident pulses whose degree of ellipticity is equal to the ratio of the material constants characterizing the local and nonlocal nonlinear optical response of the medium. It seems promising to search for possible differences in relaxation times depending on the intensity of additions to the refractive indices of the right and left circularly polarized waves by investigating the time dependence of polarization characteristics at the output of the medium.

关键词： ULTRASHORT laser pulses POLARIZATION (Electricity) NONLINEAR mechanics DISPERSION MAGNETOOPTICS NONLINEAR optics pulse-width modulation

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