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Common-Mode Voltage Harmonic Reduction in Variable Speed Drives Applying a Variable-Angle Carrier Phase-Displacement PWM Method

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ENERGIES 2021年第10期14卷 2929页

作者： Marquez, Abraham Monopoli, Vito Giuseppe Wang, Xuchen Leon, Jose I. Buticchi, Giampaolo Vazquez, Sergio Liserre, Marco Franquelo, Leopoldo G. Univ Seville Dept Elect Engn Seville 41004 Spain Politecn Bari Dept Elect & Informat Engn I-70126 Bari Italy Univ Nottingham Ningbo China Zhejiang Key Lab More Elect Aircraft Technol Ningbo 315100 Peoples R China Harbin Inst Technol Dept Control Sci & Engn Harbin 150001 Peoples R China Christian Albrechts Univ Kiel Power Elect Dept D-24118 Kiel Germany

Electric variable speed drives (VSD) have been replacing mechanic and hydraulic systems in many sectors of industry and transportation because of their better performance and reduced cost. However, the electric systems still face the issue of being considered less reliable than the mechanical ones. For this reason, researchers have been actively investigating effective ways to increase the reliability of such systems. This paper is focused on the analysis of the common-mode voltage (CMV) generated by the operation of the VSDs which directly affects to the lifetime and reliability of the complete system. The method is based on the mathematical description of the harmonic spectrum of the CMV depending on the PWM method implementation. A generalized PWM method where the carriers present a variable phase-displacement is developed. As a result of the presented analysis, the CMV reduction is achieved by applying the PWM method with optimal carrier phase-displacement angles without any external component and/or passive filtering technique. The optimal values of the carrier phase-displacement angles are obtained considering the minimization of the CMV total harmonic distortion. The resulting method is easily implementable on mostly off-the-shelf mid-range micro-controller control platforms. The strategy has been evaluated in a scaled-down experimental setup proving its good performance.

关键词： power converters harmonic distortion pulse-width modulation metaheuristic search algorithms

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Comprehensive Study Of Cascade Multilevel Inverters With Three Level Cells 7

Comprehensive Study Of Cascade Multilevel Inverters With Thr...

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7th IEEE International Conference on Energy Smart Systems (IEEE ESS)

作者： Plakhtii, Oleksandr Nerubatskyi, Volodymyr Khomenko, Igor Tsybulnyk, Vladyslav Syniayskyi, Andrii Ukrainian State Univ Railway Transport Dept Elect Power Engn Elect Engn & Electromech Kharkiv Ukraine Natl Tech Univ KhPI Dept Elect Transmiss Kharkiv Ukraine Private JSC ELAKS Kharkiv Ukraine Ltd Liabil Co VO OWEN Kharkiv Ukraine

ISBN: (纸本)9781728197876

The results of a study of a three-phase cascade multilevel inverter with various topologies and modulation algorithms are presented. It is proposed to use the topology of a cascade multilevel inverter with three-level single-phase bridges, which, if available, can significantly improve the output voltage and output current quality. The parameters of the electric power quality are studied in the implementation of various modulation algorithms: level-shifted pulse width modulation and phase-level-shifted pulse width modulation. The possibility of improving the quality of the output voltage when using interleaving in pulse-width modulation channels of individual bridges is investigated. Presented results of simulation conducted in the environment of Matlab / SymPowerSystems.

关键词： cascade multilevel voltage inverter pulse-width modulation switching frequency Fourier-analysis harmonic distortion power quality

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Description of processes in an active front-end with a fourth branch 11

Description of processes in an active front-end with a fourt...

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11th International Conference on Electrical Power Drive Systems (ICEPDS)

作者： Ioffe, Igor Ziuzev, Anatolii Kostylev, Aleksey Ural Fed Univ Elect Drives Dept Ekaterinburg Russia

ISBN: (纸本)9781728165387

Neutral wire is used in multiple active front-end application. Some of these applications are single phase loads and maintaining system stability in case of emerging unsymmetrical components, which can lead to malfunction and device failure. In such cases neutral wire potential can be middle point of DC-link, what leads to capacitor separation, but also can be implemented as additional arm, leading to full DC-link voltage utilization and additional control channel for zero symmetrical component in case of unsymmetrical load. In order to perform control system synthesis for such a complicated object, knowledge of its complex mathematical model is required. Four arms active front-end mathematical model is developed for analysis and control system development, featuring phase-coordinates usage and taking into account multiple peculiarities of this converter. Diagrams of main voltages and currents components are derived from model research.

关键词： Active front-end zero symmetrical component inverse symmetrical component four arms converter neutral wire pulse-width modulation solid-state converter

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A Random modulation Spread-Spectrum Digital PWM for a Low System Clock Digital Buck Converter

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IEEE ACCESS 2021年 9卷 156663-156671页

作者： Moon, Chan-Ho Chen, Ching-Jan Lee, Seong-Won Hanwha VisionNext Seongnam 13488 South Korea Natl Taiwan Univ Dept Elect Engn Taipei 10617 Taiwan Kwangwoon Univ Dept Comp Engn Seoul 01897 South Korea

The need for a high-efficiency power system has emerged since many IoT devices are mainly operated by batteries. A power system with analog control can have a high control bandwidth, but it is relatively vulnerable to noise disturbances and may suffer from control problems. On the other hand, a digitally controlled power system has high reliability and great controllability at the expense of switching noise and EMI issues. To implement a digitally controlled PWM with high resolution and low EMI, this study proposes a random carrier frequency modulation with dithered duty cycle method, where wide spectrum dithering and random modulation of spread spectrum PWM are tightly integrated. The proposed system was not only able to suppress voltage ripples, but also possible to minimize the occurrence of dependent frequencies due to the fixed dithering pattern. The spectrum of the output voltage showed that the switching frequency component was reduced by about 6.1dB and the output voltage ripples was also reduced compared to the existing PWM techniques.

关键词： pulse width modulation Electromagnetic interference modulation Switches Control systems Frequency modulation Switching frequency Digitally controlled buck converter spread spectrum dithering pulse-width modulation

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Control Algorithms Based on Load Angle and Phase Current Difference for Traction Switched Reluctance Motor 61

Control Algorithms Based on Load Angle and Phase Current Dif...

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61st IEEE Annual International Scientific Conference on Power and Electrical Engineering of Riga-Technical-University (RTUCON)

作者： Sejejs, Karlis Kamolins, Edmunds Gorobetz, Mikhail Potapovs, Andrejs JSC Riga Elect Machine Bldg Works 53 Ganibu Dambis LV-1005 Riga Latvia Riga Tech Univ 1 Kalku LV-1658 Riga Latvia

ISBN: (纸本)9781728195100

The goal of this research is to propose a simple and inexpensive solution to increase the reliability of the electric vehicle with traction switched reluctance motor (SRM) by the modification of control algorithm that is based not only on rotary encoder data but also on single-phase current. The paper presents the research of traction SRM, describes the developed control algorithms based on load angle detection by a rotary encoder and proposes a novel modified algorithm based on the difference of load-dependent variable phase current fragment. Test bench with SRM drive is developed and developed control algorithms are implemented in MCU software. Experimental results show the workability of the developed algorithms proving the opportunity to use single-phase current sensor for control of SRM with variable load.

关键词： digital control rotary encoder position detection pulse-width modulation switched reluctance machine control algorithms

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Silicon-Photonic Matrix Switches and Control Technologies to Accelerate Switching Speed 4

Silicon-Photonic Matrix Switches and Control Technologies to...

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4th International Conference on Photonics Solutions (ICPS)

作者： Matsuura, Hiroyuki Suzuki, Keijiro Konoike, Ryotaro Ikeda, Kazuhiro Kawashima, Hitoshi Namiki, Shu Natl Inst Adv Ind Sci & Technol 1-1-1 Umezono Tsukuba Ibaraki Japan

ISBN: (数字)9781510634305

ISBN: (纸本)9781510634305

Optical devices based on silicon photonic technology are very important as supporting current and future communication systems in terms of their scale of integration and productivity. Although various devices have been proposed and realized using silicon photonics technology, this paper describes an optical path switch combining a large number of 2x2-unitswitches loaded with electrical heaters on a Mach-Zehnder interferometer (MZI). We have been developed 8x8 and 32x32 optical matrix switches, which employ a path-independent-insertion-loss (PILOSS) configuration that has a feature of the same device count on the any path of the connection. The PILOSS structure has a feature of Strictly-non-blocking, which can connect any input port to any output port without changing existing connections when making a new connection. Each heater of the optical switch is driven by pulse-width-modulation (PWM) generated by a Field Programmable Gate Array (FPGA). The calibration of the pulse width according to the 2x2-unit switch state (Cross or Bar) is performed on all of the MZIs in advance, and the values are stored in a table of the FPGA. Separately, Cross / Bar state tables corresponding to the connection pattern of the optical input port and output port are prepared, and the pulse width switching according to the state table is simultaneously performed based on a switching command from the upper layer controller. It takes a certain amount of time to change the heater temperature of the MZI arm for switching. However, it is possible to shorten the switching time by applying a signal named "Turbo pulse" for a short term at the transition. When the temperature is raised by the heater, the switching can be speeded-up by applying a continuous high-level voltage to the heater temporarily. Even in the case of the temperature drops, the switching time can be accelerated by applying a continuous high-level voltage to the heater on the other arm of the MZI. The switching time, which was ac

关键词： Optical matrix switch Silicon photonics Strictly-non-blocking switch Mach-Zehnder interferometer Heater controlled pulse-width modulation Field programmable gate array Switching-time acceleration

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Efficiency Improvement of Step-Up Series Resonant DC-DC Converter in Buck Operating Mode 61

Efficiency Improvement of Step-Up Series Resonant DC-DC Conv...

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61st IEEE Annual International Scientific Conference on Power and Electrical Engineering of Riga-Technical-University (RTUCON)

作者： Sidorov, Vadim Chub, Andrii Vinnikov, Dmitri Tallinn Univ Technol Dept Elect Power Engn & Mechatron Tallinn Estonia

ISBN: (纸本)9781728195100

The paper focuses on the galvanically isolated series-resonant dc-dc converter (SRC) operating at low values of the quality factor of the resonant tank. The SRC topology is considered as a step-up front-end dc-dc converter with buck-boost functionality for integration of renewable energy sources in dc microgrids. The input voltage range could be expanded significantly by implementing different buck control methods at the constant switching frequency. Moreover, an additional control degree of freedom allowing optimization of the converter operation is topology reconfiguration between the full-bridge mode and the half-bridge mode. The paper describes the transition between these two modes of the input-side full-bridge inverter by applying hybrid phase shift modulation and asymmetrical pulse-width modulation, respectively. Experimental results show the operation of the converter in a wide input voltage range and transition transients between the two modes.

关键词： Series resonance dc-dc converters phase shift modulation pulse-width modulation dc microgrid voltage range

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Functional Measuring Generator with pulse Current Stabilization

Functional Measuring Generator with Pulse Current Stabilizat...

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Global Smart Industry Conference (GloSIC)

作者： Galiev, A. L. Yumagulov, N., I Topolsky, D., V Bashkir State Univ Dept Gen & Theoret Phys Sterilitamak Branch Sterlitamak Russia Nizhnevartovsk State Univ Dept Educ Phys & Math Nizhnevartovsk Russia South Ural State Univ NRU Dept Theoret Fdn Elect Engn Chelyabinsk Russia

ISBN: (纸本)9781728180755

Smart sensors are a source of objective and reproducible information on quantities characterizing the quality of production processes, the condition and properties of objects of study. The paper presents the results of a study of a pulsed current stabilizer, which provides simultaneous registration of the resistance value of the site of the object of study. The developed device provides an energy mode of influence on the object of study with a given current value. A control circuit using pulse-width modulation with a constant pulse repetition rate stabilizes the current. The constancy of the pulse repetition rate is a distinctive feature of the stabilizer in question, which allows for a fixed constant value of the generator current to significantly expand the range of controlled resistances of the object under study. In the work, the optimal range of current values is recommended, at which the diagnostic value of the received information is preserved and the most economical mode of operation of the device is provided.

关键词： pulse-width modulation monostable multivibrator stabilizer differential amplifier resistance value recorder

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Prediction of DC-Link Voltage Switching Ripple in Three-Phase Four-Leg PWM Inverters

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ENERGIES 2021年第5期14卷 1434-1434页

作者： Mandrioli, Riccardo Viatkin, Aleksandr Hammami, Manel Ricco, Mattia Grandi, Gabriele Univ Bologna Dept Elect Elect & Informat Engn I-40136 Bologna Italy

This paper presents a thorough prediction of DC-link voltage switching ripples in the three-phase four-leg inverters operating in balanced and unbalanced working conditions. The unbalanced modes examined here employ the highest degree of AC current imbalance while still preserving three-phase operation. This behavior can be found in many grid-connected or standalone grid-forming three-phase converters that supply "heavy" single-phase loads, comprising a recent trend in smart-grid, smart electric vehicle (EV)-charging applications. In this sense, for instance, the smart EV chargers might be employed in conditions when different power is drawn/injected from/to the grid, providing power conditioning services to the latter. The analysis of three-phase four-leg inverters is then extended to single-phase operations typical of home-charging or vehicle-to-home (V2H) applications. Their performances in terms of DC-link voltage switching ripple are demonstrated. Two of the most common carrier-based PWM modulation techniques are employed to drive the three-phase inverter-namely, sinusoidal PWM and centered PWM (carrier-based analogy of the space vector modulation). The derived mathematical expressions of peak-to-peak and RMS values of DC-link voltage switching ripple for balanced and unbalanced conditions are handy for designing the associated DC-link capacitor and estimating the overall efficiency of the converter. Extensive numerical simulations and experimental tests have been performed to validate the presented analytical developments.

关键词： voltage ripple voltage source inverter four-wire four-leg inverter DC-link switching ripple harmonic pollution pulse-width modulation EV charging on-board charger

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OPTIMISATION OF A POLARISATION NEPHELOMETER

LIGHT & ENGINEERING

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LIGHT & ENGINEERING 2021年第2期29卷 87-95页

作者： Oshlakov, Victor G. Shcherbakov, Anatoly P. RAS Siberian Branch VE Zuev Inst Atmospher Opt Tomsk Russia

An analysis of the influence caused by polarization nephelometer parameters on the scattering matrix measurement accuracy in a non-isotropic medium is presented. The approximation errors in the actual scattering volume and radiation beam by an elementary scattering volume and an elementary radiation beam are considered. A formula for calculating the nephelometer base is proposed. It is shown that requirements to an irradiation source of a polarizing nephelometer, i.e. mono-chromaticity and high radiation intensity and directivity in a wide spectral range can be satisfied by a set of high brightness LEDs with a radiating (self-luminous) small size body. A 5-wavelength monochromatic irradiation source, with an emission flux of (0.15-0.6) W required for a polarization nephelometer, is described. The design of small-sized polarizing phase control units is shown. An electronic circuit of a radiator control unit" based on an AVR-Atmega 8-bit micro-controller with feedback and drive control realized by means of an incremental angular motion sensor and a software PID controller 2 is presented. Precise and smooth motion of the radiator is ensured by standard servo-driven numerical control mathematics and the use of precision gears. The system allows both autonomous adjustment of the radiator's reference positions and adjustment by means of commands from a personal computer. Both the computer and microcontroller programs were developed with the use of free software, making it possible to transfer the programs to Windows-7(10), Linux and embedded Linux operating systems. Communication between the radiator's position control system and the personal computer is realised by means of a standard noise immune USB-RS485 interface.

关键词： polarization nephelometer non-isotropic scatterer scattering matrix elementary volume elementary light beam approximation error LED encoder microprocessor precision position control motor power bridge pulse-width modulation PID controller

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