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Analysis of Vibration Characteristics Considering the modulation effect According to Rotor Bars of Induction Motor for EVs

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JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY 2025年第3期20卷 1405-1415页

作者： Kim, Nam-Ho Cho, Jae-Hoon Lee, Jin Hwan Jung, Sang-Yong Sungkyunkwan Univ Dept Elect & Comp Engn Suwon South Korea Chonnam Natl Univ Dept Elect Engn Gwangju South Korea

The predominant method for mitigating vibrations in electric vehicle (EV) propulsion motors involves utilizing electromagnetic strategies to reduce air-gap electromagnetic force (AEMF) orders. This study investigates the origins of AEMFs that significantly induce vibrations in induction motor (IM) models with 6-poles and 54-slots. Initially, it is revealed through spatial harmonic analysis of winding distribution factors that harmonics of same magnitude to the fundamental component play a crucial role in the harmonics of the armature reaction (critical order). Subsequently, it analytically examines and compares the sources of vibration orders of AEMFs. The conditions for determining the rotor slot number are provided to avoid vibration orders that induce significant vibrations. To prove this, this paper utilizes 2D-FEA to calculate AEMFs at rated operating point for both the 44-bar and 70-bar models, confirming the substantial contribution of the critical order of MMF to lower vibration orders in the 44-bar model. Conversely, the 70-bar model exhibits significantly reduced forces due to the absence of correlation between lower vibration orders and the critical order of MMF. After that, considering the modulation effect of high vibration orders caused by rotor slots and slip effects, the forces are calculated by vector summation with lower vibration orders for all operating speeds. This comparison confirms that the 44-bar model generates larger AEMFs compared to the 70-bar model. Finally, through coupling analysis, it demonstrates that the 70-bar model is advantageous in terms of vibration compared to the 44-bar model.

关键词： Air-gap electromagnetic force Distribution factor Induction motor modulation effect Vibration

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Investigation of Electromagnetic Forces Acting on Rotor Considering modulation effect of Surface-Mounted Pole Structure

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IEEE TRANSACTIONS ON TRANSPORTATION ELECTRIFICATION 2025年第2期11卷 5723-5733页

作者： Wang, Wenting Wu, Lijian Song, Pingyue Wei, Guoqiang Wang, Xufeng Lyu, Wei Zhejiang Univ Coll Elect Engn Hangzhou 310027 Peoples R China Shanghai Elect Wind Power Grp Co Ltd Hangzhou 310027 Peoples R China

While the modulation effect of stator teeth on electromagnetic forces (EFs) acting on the stator surface has been extensively studied, EFs acting on the rotor with the corresponding effect considered remain largely unexplored. This article reveals that the surface-mounted magnet poles can act as modulators of EF harmonics, which indicates that high-order EF harmonics also contribute to low-order mode rotor vibration. To specifically explain the force modulation effect of magnets, this study introduces an intuitive masking function. Furthermore, an analytical procedure is developed to reidentify dominant field harmonic sources and EF harmonics of low-order modulated forces, with both field and force modulation effects considered. The field component contribution is analytically quantified by the amplitude-, force modulation-, and field modulation coefficients. Subsequently, the influence of the pole arc ratio and tooth-tip arc ratio is investigated for low-vibration design. The findings show that the contribution of a high-order EF harmonic to a certain modulated force can be comparable to that of a low-order EF harmonic. In addition, there exists an overlapping range of the above two design parameters to achieve low vibration and high torque. The analysis is validated by the finite element method and experiments.

关键词： Electromagnetic force (EF) external rotor (ER) modulation effect modulation effect surface-mounted permanent magnet machines surface-mounted permanent magnet machines vibration vibration vibration

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modulation effect and inverse synthetic aperture radar imaging of rotationally symmetric ballistic targets with precession

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IET RADAR SONAR AND NAVIGATION 2013年第9期7卷 950-958页

作者： Pan, Xiao-yi Wang, Wei Liu, Jin Ma, Liang Feng, De-jun Wang, Guo-yu Natl Univ Def Technol Coll Elect Sci & Engn Changsha 410073 Hunan Peoples R China

The modulation effect of rotationally symmetric ballistic targets (BTs) with precession is concerned. To further approach the actual case, the modulation in amplitude and Doppler is considered in the radar backscattering and revealed by short-time Fourier transform (STFT). The results indicate that the micro-Doppler (m-D) effect induced by periodical precession is not represented as a sinusoidal modulation on the edge of BTs as usual, and the amplitude modulation may lead to discontinuity of time-frequency curve. The phenomenon in STFT is confirmed by both simulated and real data from a BT model with precession measured in the microwave anechoic chamber. Based upon the measured data, inverse synthetic aperture radar imaging results have been obtained by smoothed pseudo Wigner-Ville time-frequency distribution.

关键词： amplitude modulation anechoic chambers (electromagnetic) backscatter ballistics Doppler radar electromagnetic wave scattering Fourier transforms radar imaging synthetic aperture radar time-frequency analysis Wigner distribution modulation effect inverse synthetic aperture radar imaging rotationally symmetric ballistic target BT amplitude modulation radar backscattering short-time Fourier transform STFT microDoppler effect periodical precession sinusoidal modulation microwave anechoic chamber smoothed pseudoWigner-Ville time-frequency distribution

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modulation effect of Slotted Structure on Vibration Response in Electrical Machines

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2019年第4期66卷 2998-3007页

作者： Fang, Haiyang Li, Dawei Qu, Ronghai Yan, Peng Huazhong Univ Sci & Technol Sch Elect & Elect Engn State Key Lab Adv Electromagnet Engn & Technol Wuhan 430074 Hubei Peoples R China

Analytical method for vibration and noise prediction in electrical machines is computationally efficient and widely used. In conventional analytical approaches, the slotted stator is simplified as a cylinder, and it is generally believed that the vibration is more sensitive to the air-gap forces with low spatial orders, hence, those high-order air-gap forces are usually neglected. In this paper, the force distribution on the slotted stator is analyzed using a force transformation model and a new phenomenon, i.e., the modulation effect, is found, which indicates that a high-order air-gap force could also induce a low-mode stator vibration with a large amplitude. As a result, the conventional analytical methods are not so accurate for machines with a strong modulation effect, such as fractional-slot concentrated-winding machines. The existence condition for the modulation effect is also discussed in this paper. Finite-element analysis and experiments have been done to verify the analysis results.

关键词： Analytical method high-order air-gap force modulation effect slotted stator vibration

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modulation effect produced by adjacent AC voltage on the characteristics of negative corona current pulses in a wire-cylinder electrode configuration

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JOURNAL OF ELECTROSTATICS 2016年 84卷 54-62页

作者： Wang, Zhenguo Lu, Tiebing Bian, Xingming Hiziroglu, Huseyin R. Li, Xuebao North China Elect Power Univ State Key Lab Alternate Elect Power Syst Renewabl Beijing 102206 Peoples R China Kettering Univ Dept Elect & Comp Engn Flint MI 48504 USA

In this paper, a wire-cylinder electrode system was designed to study the negative DC corona pulses due to the influence of AC voltage applied to an adjacent conductor. The corona onset voltage and distribution pattern and the parameters of the corona current pulses such as the rise time, pulse duration and the average pulse amplitude are systematically analyzed. The AC voltage is found to have an interesting modulation effect on the time interval of the current pulses. At last, based on a simplified ion cloud model, a full explanation is given to reveal the mechanism behind the influence of the AC voltage on negative DC corona. (C) 2016 Elsevier B.V. All rights reserved.

关键词： DC corona discharge Corona current pulses AC voltage modulation effect

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modulation effect of carbon quantum dots in organic electroluminescent devices

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ORGANIC ELECTRONICS 2017年 51卷 314-321页

作者： Qian, Kun Li, Hairong Zheng, Bo Chang, Fangzhi Lei, Qi Han, Genliang Song, Yuzhe Liu, Su Wei, Yongzhi Lanzhou Univ Sch Phys Sci & Technol Lanzhou 730000 Peoples R China Gansu Acad Sci Inst Sensor Technol Lanzhou 730000 Peoples R China Lanzhou Univ Minist Educ Key Lab Special Funct Mat & Struct Design Lanzhou 730000 Peoples R China Lanzhou Univ Minist Educ Key Lab Magnetism & Magnet Mat Lanzhou 730000 Peoples R China

In this work, carbon quantum dots (CQDs) are embedded as a functional material into white-organic-light-emitting diodes (WOLEDs) devices with a structure of dual-light-emitting layer. When the forward voltage is applied on devices ranging from 14 V to 22 V, the CIE coordinates of CQDs WOLEDs changed from (0.27,0.29) to (0.34,0.37) which exhibits linear optical modulation effect. Meanwhile the as-fabricated CQDs WOLEDs obtain excellent optical and electrical properties. By embedding CQDs, WOLEDs with a low turn-on voltage of 12 V which is 40% lower than reference devices can be achieved. Moreover, the devices could also obtain high luminous brightness with a lower voltage. Such superior properties are attributed to the CQDs multiple exciton generation (MEG) effect. The results demonstrate that CQDs as functional materials of WOLEDs may open up new thoughts to develop the optically modifiable WOLEDs and the low power consumption optoelectronic devices. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Organic light-emitting diodes Carbon quantum dots modulation effect Performance improvement

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modulation effect in adjacent dual metal single atom catalysts for electrochemical nitrogen reduction reaction

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Chinese Chemical Letters 2022年第3期33卷 1455-1458页

作者： Xiaonan Zheng Yang Liu Yu Yan Xiaoxiao Li Yuan Yao MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage&State Key Laboratory of Advanced Welding and Joining School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150080China

Nitrogen reduction reaction (NRR) is a clean mode of energy conversion and the development of highly efficient NRR electrocatalysts under ambient conditions for industrial application is still a big challenge. Metal-nitrogen-carbon (M-N-C) has emerged as a class of single atom catalyst due to the unique geometric structure, high catalytic activity, and clear selectivity. Herein, we designed a series of dual metal single atom catalysts containing adjacent M-N-C dual active centers (MN_(4)/M'N_(4)-C) as NRR electrocatalysts to uncover the structure-activity relationship. By evaluating structural stability, catalytic activity, and selectivity using density functional theory (DFT) calculations, 5 catalysts, such as CrN_(4)/M'N_(4)-C (M’ = Cr, Mn, Fe, Cu and Zn), were determined to exhibit the best NRR catalytic performance with the limiting potential ranging from -0.64 V to -0.62 V. The CrN_(4) center acted as the main catalytic site and the adjacent M'N_(4) center could enhance the NRR catalytic activity by modulation effect based on the analysis of the electronic properties including the charge density difference, partial density of states (PDOS), and Bader charge variation. This study offers useful insights on understanding the structure-activity relationship of dual metal single atom catalysts for electrochemical NRR.

关键词： Nitrogen reduction reaction Electrocatalysts Density functional theory Dual metal single atom catalysts modulation effect

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modulation effect in multiphoton pair production

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PHYSICS LETTERS B 2017年 768卷 174-179页

作者： Sitiwaldi, Ibrahim Xie, Bai-Song Beijing Normal Univ Minist Educ Key Lab Beam Technol & Mat Modificat Beijing 100875 Peoples R China Coll Nucl Sci & Technol Beijing 100875 Peoples R China Beijing Radiat Ctr Beijing 100875 Peoples R China

We investigate the electron-positron pair production process in an oscillating field with modulated amplitude in the quantum kinetic formalism. By comparing the number density in the oscillating field with and without modulation, we find that the pair production rate can be enhanced by several orders when the photon energy just reaches the threshold with the help of shifted frequency due to modulation. We also detect the same effect in a pulse train with subcycle structure. We demonstrate that the frequency threshold can be lowered by the frequency of the pulse train due to the modulation effect. We also find that the momentum distribution for a N-pulse train can reach N-2 times the single pulse at the maximum value and the number density as a function of pulse number follows the power law with index 1.6 when the modulation effect is maximized. (C) 2017 The Authors. Published by Elsevier B.V.

关键词： Pair production modulation effect Pulse train

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modulation effect of Lead Zirconate Titanate for Zinc Oxide Channel Resistance in Ferroelectric Field effect Transistor

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FERROELECTRICS 2011年第1期421卷 92-97页

作者： Jia, Ze Zhang, Ming-Ming Ren, Tian-Ling Tsinghua Univ Inst Microelect Tsinghua Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China

In this work, bottom-gate-type ferroelectric field effect transistors (FeFET) are fabricated. Sol-gel prepared aluminum doped zinc oxide (ZnO) and Lead Zirconate Titanate (PZT) are applied as channel and gate dielectric respectively. Uniform and dense ZnO is fabricated and good conductivity is obtained. Polarization of PZT is found to decrease after Al doped ZnO is prepared on it. Obvious modulation effects of PZT on the channel are found. Capacitance of the channel and gate dielectric stacked structure is tested. And channel resistance is found to change with the direction of remnant polarization in PZT. Mechanisms of the modulation effects are investigated.

关键词： FeFET ZnO modulation effect channel resistance

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modulation effect of Lead Zirconate Titanate for Zinc Oxide Channel Resistance in Ferroelectric Field effect Transistor

Modulation Effect of Lead Zirconate Titanate for Zinc Oxide ...

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Joint Meeting of the 19th IEEE International Symposium on the Applications of Ferroelectrics/10th European Conference on the Applications of Polar Dielectrics

作者： Jia, Ze Zhang, Ming-Ming Ren, Tian-Ling Tsinghua Univ Inst Microelect Tsinghua Natl Lab Informat Sci & Technol Beijing 100084 Peoples R China

关键词： FeFET ZnO modulation effect channel resistance

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