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Complementary double pulse-width-modulation for 3D shape measurement of complex surfaces

OPTICS AND LASER TECHNOLOGY 2023年第1期167卷

作者： Zheng, Yanjun Gao, Zhisheng Zuo, Chenglin Xihua Univ Sch Comp & Software Engn Chengdu 610039 Peoples R China China Aerodynam Res & Dev Ctr Low Speed Aerodynam Inst Mianyang 621000 Peoples R China

pulse-width modulation has the advantages of fast projection speed and high precision. However, when it is used to measure the three-dimensional (3D) shape of complex surfaces, it suffers from harmonic interference caused by slight defocusing and is sensitive to pixel oversaturation. To achieve high-speed and accurate 3D measurement of complex surfaces using this method, in this paper, a complementary double pulse-width -modulation (CDPWM) is proposed and used to generate ideal phase-shift fringe patterns. In our method, a triangular carrier signal with a zero phase is first used to generate a set of double pulse-width-modulation (DPWM) patterns, and then a triangular carrier signal with a phase of ��/2 is used to generate another set of DPWM patterns. Then, the CDPWM is obtained by fusing these two sets of DPWM patterns. We demonstrate that CDPWM can tremendously suppress harmonic interference so that in practical applications, a smaller defocus can be used to robustly reconstruct complex surfaces. Moreover, it is proved that the patterns corresponding to the ��/2 phase are the compensation patterns of the patterns corresponding to the zero phase, which enables CDPWM to eliminate or reduce the pixel oversaturation effect caused by a surface with a high dynamic range. Through experiments on simulated and real data, the proposed method is shown to substantially improve the phase quality and measurement accuracy over a wide range of fringe periods (e.g., from 18 to 912 pixels), especially when the defocus level is low. Different camera exposure times are used to demonstrate the robustness of the proposed method to oversaturated pixels. Furthermore, we measured a set of ice surfaces and a metal surface containing both low-and high-reflection areas. The projector was set to a slight defocus, which better preserved the binary characteristics of the patterns it projected. The measurement results proved our method can significantly improve the measurement accuracy

关键词： Complementary pattern pulse-width-modulation High dynamic range 3D measurement Phase retrieval

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Voltage-Fed single stage inverter for generating systems with Multi-Input inverter using pulse width modulation

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SUSTAINABLE ENERGY TECHNOLOGIES AND ASSESSMENTS 2023年 60卷

作者： Senthilkumar, T. Sivaraju, S. S. Ranganayaki, V. Anuradha, T. Anna Univ RVS Coll Engn & Technol Dept Elect & Elect Engn Coimbatore Tamil Nadu India Anna Univ KCG Coll Technol Dept Elect & Elect Engn Chennai Tamil Nadu India

A voltage-fed single-stage multiple-input inverter is developed for hybrid wind/photovoltaic energy generating systems. In this research proposes a revolutionary multi-input inverter that simplifies and reduces the power system's cost. Inverter comprises the DC-DC converters and full-bridge ac inverters, which are buck/buck-boost. This study proposed a multi-input converter for hybrid photovoltaic and wind energy systems, with the basis and enhanced functionalities created by the scholars included in the design. A Novel Predictive Current Control Algorithm (NPCCA) is proposed for Hybrid a renewable energy source which depends on improved space-vector pulse-width-modulation (PWM) to provide high-quality current and quick dynamic reaction to incorporate changes. Also discussed are the solar array and wind turbine output power characteristics. The Maximum Power Point-Tracking (MPPT) methodology is accomplished using the perturbation and observation methods to resist all non-linearities in the typical I-V curves. The proposed multi-input converters results in lower production costs for the converters since they use fewer semiconductors and take up less space. Soft-starting and circuit safety features are added for real-world uses. The simulation outcome of the NPCCA framework attained in terms of accuracy is 92% and efficiency is 92% when compared with the other existing approaches.

关键词： pulse-width-modulation Photovoltaic Wind Power System

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Digital removal of pulse-width-modulation-induced distortion in class-D audio amplifiers

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IET SIGNAL PROCESSING 2014年第6期8卷 680-692页

作者： Aase, Sven Ole Univ Stavanger Dept Elect Engn & Comp Sci N-4036 Stavanger Norway

In an all-digital, class-D audio amplifier, pulse-width-modulation (PWM) of a digital signal source is usually followed by a low-order analog low-pass filter to construct the analog audio waveform. This study shows how to remove the non-linear distortion usually associated with PWM, by prefiltering the digital signal prior to the PWM mapping in such a manner that the overall result is distortion-free. The prefiltering is done using computationally effective infinite-impulse-response filters combined with short-kernel anticausal finite-impulse-response filters, and relies on the interpretation of PWM as a Volterra filter. A case study is presented where a second-order Butterworth analog low-pass filter is used for reconstruction of the analog audio signal. A complete amplifier system is modelled, including upsampling, Volterra prefiltering and noise feedback coding. Computer simulations on CD music signals were performed. Using a third-order prefilter, a signal-to-noise ratio of 97-102 dB was obtained for the music signals tested. All necessary filter data needed for realisation of the prefilter are given in the Appendix.

关键词： audio-frequency amplifiers audio signal processing Butterworth filters distortion feedback low-pass filters nonlinear filters pulse width modulation signal reconstruction transient response digital removal pulse-width-modulation-induced distortion class-D audio amplifiers pulse-width-modulation PWM digital signal source low-order analog low-pass filter analog audio waveform nonlinear distortion removal digital signal pulse-code-modulated-to-PWM mapping computationally effective infinite-impulse-response filters short-kernel anticausal finite-impulse-response filters Volterra filter second-order Butterworth analog low-pass filter analog audio signal reconstruction amplifier system Volterra prefiltering noise feedback coding computer simulations CD music signals third-order prefilter signal-to-noise ratio music signals filter data

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ENNA: An Efficient Neural Network Accelerator Design Based on ADC-Free Compute-In-Memory Subarrays

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS 2023年第1期70卷 353-363页

作者： Jiang, Hongwu Huang, Shanshi Li, Wantong Yu, Shimeng Georgia Inst Technol Sch Elect & Comp Engn Atlanta GA 30332 USA

Compute-in-memory (CIM) is an attractive solution for machine learning hardware acceleration since it merges computation directly into memory arrays, performing parallel multiply-and-accumulate (MAC) operations. The primary challenge in the reported CIM designs is the analog-to-digital converters (ADCs) that digitize analog MAC values for further processing, causing accuracy loss, excessive power dissipation, latency penalty, and area overhead. In this work, we propose ENNA, a novel CIM architecture based on an ADC-free subarray design, implementing inter-array data processing in an analog manner. A lightweight input encoding scheme based on pulse-width modulation (PWM) is proposed to improve the throughput. We taped-out a prototype macro and validated the proposed ADC-free RRAM array design in TSMC 40nm process. Based on the measured silicon data, we explore the system-level performance with a partition between analog and digital processing at a level higher than the sub-array. The evaluation results show that the proposed accelerator can achieve 73.6 similar to 46.4 TOPS/VV energy efficiency and 2.3 similar to 7 TOPS throughput (normalized to binary operation) tested on various DNN models. Furthermore, we project the proposed design using a heterogeneous 3D integration (H3D) scheme, showing a 3x similar to 37x throughput improvement depending on different tasks and similar to 50% reduced area overhead compared to 2D design.

关键词： Compute-in-memory ADC-free pulse-width-modulation heterogeneous 3D integration

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Extremum-Seeking for PWM-Controlled Double-Integrator System via Nonlinear Small-Gain Approach

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS 2023年第12期70卷 5433-5441页

作者： Xu, Jingwei Jin, Zhenghong Northeastern Univ State Key Lab Synthet Automat Proc Ind Shenyang 110819 Peoples R China Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore

This study considers the extremum-seeking control problem for double-integrator system that is controlled by using the pulse-width-modulation (PWM) technique. A new class of PWM control law is presented that the state trajectories of the closed-loop system are held within a desired range. A trajectory-based analysis approach is also proposed that characterize the influence of the hybrid PWM control input. A novel hierarchical structure is developed that separates the closed-loop extremum-seeking system into the interconnected networked subsystems, which are characterized in the sense of input-to-state practical stability (ISpS) and input-to-output stability (IOpS). By using the nonlinear small-gain theorem, the stability of the ES closed-loop system is ensured so that the PWM-controlled plant can gravitate towards an appropriate region of the maximum (minimum) of the nonlinear map (which can be considered as a gradient field). Finally, numerical examples demonstrate the validity and effectiveness of our proposed design.

关键词： pulse-width-modulation input-to-output practical stability nonlinear small-gain theorem extremum-seeking

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Segregation of Additional High Frequency Harmonic Losses Created by PWM Supply 65

Segregation of Additional High Frequency Harmonic Losses Cre...

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65th IEEE Annual International Scientific Conference on Power and Electrical Engineering of Riga Technical University, RTUCON 2024

作者： Aarniovuori, Lassi Tiihonen, Matias Ahmed, Shoaib Karkkainen, Hannu Niemela, Markku Barta, Jan Vitek, Ondrej LUT School of Energy systems Lappeenranta Finland Brno University of Technology Department of Power and Electronic Engineering Brno Czech Republic

ISBN: (纸本)9798350365771

This paper describes a method for analysing high frequency harmonic losses in the rotating field machines supplied with a frequency converter. The loss segregation is mainly used in the energy efficiency classification and analysis of direct-online induction motors. Previously, there has not been a universal method to segregate the additional high frequency harmonic losses created by the PWM supply from the experimentally determined total losses of the 37-kW modern IE3 rated converter-fed induction motor. This paper demonstrates the method to segregate and analyse the high frequency harmonic losses created by the PWM supply based on the assumption that the loss component is equal to harmonic power determined from the electric power measurement from the motor terminals. The loss segregation is performed in 30 operations points in the frequency - torque plane. The drive system losses are segregated into the loss components, converter losses, motor losses, and high frequency harmonic losses. © 2024 IEEE.

关键词： efficiency experimental testing induction motor pulse-width-modulation voltage source converter

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Direct current grid-based doubly-fed induction generator wind turbines: Real-time control and stability analysis

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IET POWER ELECTRONICS 2022年第12期15卷 1158-1173页

作者： Akhbari, Allahyar Rahimi, Mohsen Khooban, Mohammad Hassan Univ Kashan Elect & Comp Engn Dept Kashan *** Iran Aarhus Univ Dept Elect & Comp Engn Aarhus Denmark

Commonly, a simple topology consisting of a single diode-rectifier and pulse-width-modulation (PWM) converter is used for the connection of the doubly-fed induction generator-based wind turbines (DFIG-WTs) to the DC grid, in which the rotor-side converter (RSC) and the stator diode-rectifier are linked to the common DC bus. But, this topology suffers from less flexibility due to the requirement of matching the stator nominal voltage with the DC grid. Hence, in this paper, a buck converter is added to the DFIG-WT topology and two methods are proposed to control the power converters, where in the first one, the RSC regulates the active power and stator flux linkage, and in the second one, the RSC regulates the DC bus voltage and stator flux linkage. Then, the small-signal stability and the performance of the DFIG-WT system with the mentioned control strategies are compared analytically and through the off-line simulations. At last, a real-time hardware-in-the-loop (HIL) emulation-based OPAL-RT is carried out to investigate the performance of the proposed control methods from a practical perspective.

关键词： small-signal stability DC grid stators power generation control pulse-width-modulation real-time control diodes stator flux linkage PWM stability analysis direct current grid-based doubly-fed induction generator wind turbines pulse width modulation rotor-side converter asynchronous generators stator diode-rectifier machine control stator nominal voltage rotors HIL power convertors power grids topology DFIG-WT system hardware-in-the-loop simulation wind turbines rectifiers power system stability real-time hardware-in-the-loop emulation-based OPAL-RT buck converter RSC DC bus voltage voltage control power converters magnetic flux single diode-rectifier active power

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Ensuring a Smooth Transition from Linear modulation, through Overmodulation, and into Six-Step

Ensuring a Smooth Transition from Linear Modulation, through...

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2023 IEEE Energy Conversion Congress and Exposition, ECCE 2023

作者： Sun, Yang Secrest, Caleb W. Power Drive Systems BorgWarner Inc NoblesvilleIN United States

ISBN: (纸本)9798350316445

Six-step operation of a motor drive system can increase overall efficiency and maximize peak power output. It is generally achieved as an extension of an overmodulation algorithm. However, due to the nature of sampling and execution processes in a digital signal processor, if fully relying on existing state-of-the-art overmodulation techniques, then undesirable voltage imbalance and current oscillation can be introduced when transitioning into six-step operation. This is especially true during low pulse-ratio operation. This paper presents a method to achieve a smooth transition from linear modulation, through overmodulation, and into six-step for a 3-phase motor drive system. It is proposed that an averaged ideal volt-second solution coupled with manipulation of the pulse-width-modulation carrier waveform can be used to ensure a smooth transition. © 2023 IEEE.

关键词： overmodulation pulse-width-modulation six-step

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DAB-Based Common-Mode Injection in Three-Phase Four-Wire Inverters 16

DAB-Based Common-Mode Injection in Three-Phase Four-Wire Inv...

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16th International Conference on Compatibility, Power Electronics, and Power Engineering (CPE-POWERENG)

作者： Mandrioli, Riccardo Ricco, Mania Grandi, Gabriele Pereira, Thiago A. Liserre, Marco Univ Bologna Dept Elect Elect & Informat Engn Bologna Italy Christian Albrechts Univ Kiel Chair Power Elect Kiel Schleswig Holst Germany

ISBN: (纸本)9781665496780

Three-phase four-wire DC/AC converters are crucial for applications like electric vehicle (EV) chargers and solid-state transformers (SST). For ensuring galvanic isolation, dual-active-bridge (DAB) converters are often selected to be associated with the front-end AC/DC stage. In this context, this paper explores the possibility of delivering and driving the additional neutral wire directly from the DAB converter without introducing any additional and dedicated fourth-leg, as well as an independent-controlled neutral module. Further, a modified single phase-shift strategy capable of providing common-mode injection is presented and discussed under different operating conditions and modulation schemes. Finally, numerical results are presented to validate the correctness of all developments.

关键词： dual-active-bridge four-wire inverter EV charging smart-transformer pulse-width-modulation

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A Power Quality Assessment of Electric Submersible Pumps Fed by Variable Frequency Drives under Normal and Failure Modes

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ENERGIES 2023年第13期16卷 5121页

作者： Lingom, Pascal M. M. Song-Manguelle, Joseph Betoka-Onyama, Simon Pierre Nyobe-Yome, Jean Maurice Doumbia, Mamadou Lamine Univ Quebec Trois Rivieres Dept Elect & Comp Engn Trois Rivieres PQ G8Z 4M3 Canada Univ Douala Elect Engn Dept Douala 3QPW P9M Cameroon

This paper proposed a simplified modeling approach for a power quality (PQ) assessment of Electric Submersible Pumps (ESP) systems supplied by the two-level, the neutral-point-clamped three-level, and the cascaded H-bridge (CHB) multilevel inverter VFD topologies. The VFD switching function models and their analytical expressions are proposed to understand how they can create high-frequency components that might excite the resonance mode in a transmission cable or a rotating shaft system. Voltage, current, and motor airgap torque harmonics induced by each VFD topology in a balanced operation mode are derived and correlated to the PWM carrier and motor operating frequencies. The motor airgap harmonics are calculated based on Concordia's transformation of voltages and currents in & alpha;& beta;-plan. These harmonic components are represented in the form of Campbell diagrams. An analysis of harmonics under unbalanced conditions was also conducted in a CHB VFD topology-powered ESP system with failed and bypassed cells. The investigated modulation technique is a neutral-shift PWM method that enables the system to operate balanced line-line voltages even if the line-neutral voltages are unbalanced. The effects of modifying the electrical spectrum using the neutral-shift PWM method on electrical and mechanical spectra are analyzed. The results of the Matlab/Simulink-based simulation show that the proposed full ESP system model is highly accurate in both normal and failure modes. The results are consistent with theoretical predictions and are graphically shown in the time and frequency domains for easy analysis. Hybrid experimental-numerical results on a reduced-scale laboratory setup are also discussed to confirm the correctness of the suggested developments.

关键词： common-mode voltage electric submersible pumps harmonics multilevel inverter neutral-point-clamped inverter pulsating torque pulse-width-modulation power quality

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