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Broken Rotor Bar Fault Detection of Induction motors Using a Joint Algorithm of Trust Region and Modified Bare-bones Particle Swarm Optimization

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Chinese Journal of Mechanical Engineering 2019年第1期32卷 65-78页

作者： Panpan Wang Liping Shi Yong Zhang Yifan Wang Li Han School of Electrical and Power Engineering China University of Mining & Technology

A precise detection of the fault feature parameter of motor current is a new research hotspot in the broken rotor bar(BRB) fault diagnosis of induction motors. Discrete Fourier transform(DFT) is the most popular technique in this field, owing to low computation and easy realization. However, its accuracy is often limited by the data window length, spectral leakage, fence e ect, etc. Therefore, a new detection method based on a global optimization algorithm is proposed. First, a BRB fault current model and a residual error function are designed to transform the fault parameter detection problem into a nonlinear least-square problem. Because this optimization problem has a great number of local optima and needs to be resolved rapidly and accurately, a joint algorithm(called TR-MBPSO) based on a modified bare-bones particle swarm optimization(BPSO) and trust region(TR) is subsequently proposed. In the TR-MBPSO, a reinitialization strategy of inactive particle is introduced to the BPSO to enhance the swarm diversity and global search ability. Meanwhile, the TR is combined with the modified BPSO to improve convergence speed and accuracy. It also includes a global convergence analysis, whose result proves that the TR-MBPSO can converge to the global optimum with the probability of 1. Both simulations and experiments are conducted, and the results indicate that the proposed detection method not only has high accuracy of parameter estimation with short-time data window, e.g., the magnitude and frequency precision of the fault-related components reaches 10^(-4), but also overcomes the impacts of spectral leakage and non-integer-period sampling. The proposed research provides a new BRB detection method, which has enough precision to extract the parameters of the fault feature components.

关键词： Fault detection Broken rotor bars Induction motors Bare-bones particle swarm optimization Trust region

Molecular motors—Self-Organization of Cytoskeletal Network

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Yangtze Medicine 2017年第4期1卷 202-215页

作者： Kishore Dutta Department of Physics Handique Girls’ College Guwahati India

Molecular motors play an important role in the organization of cytoskeletal filament networks. These nanometer-sized natural molecular machines opened up a new frontier of nano-technology. This article describes biomolecular nano-machines, their internal structures, and dynamical interactions between molecular motors and their molecular tracks which reorganize a network of long protein filaments, particularly during cell division to form cytoskeleton of daughter cells. Towards the end, the article also takes up some still-to-be resolved matters and prospects for future developments in this exciting multidisciplinary area of science.

关键词： Cell Motility Molecular motors Self-Organization

OPTIMUM CONTROL OF LARGE D. C. motors

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Science in China,Ser.A 1960年第4期 545-558页

作者：叶正明 Institute of Automation

Large D. C. motors used in process machinery, such as in the main drive and sub-drive of rolling mills, electric shovels, and hoisting machines in the mine, etc., often work in repeatedly reversing conditions. Since s... 详细信息

关键词：田刀 motors OPTIMUM CONTROL OF LARGE D

Numerical Modeling of the Coupled Electromagnetic and Mechanical Phenomena of Linear Stepping motors

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Journal of Electromagnetic Analysis and Applications 2012年第1期4卷 1-8页

作者： Mustapha Zaouia Nacereddine Benamrouche M'hemed Rachek 不详

In this paper, we propose an electromagnetic-mechanical model based on the finite element and Macro-Element (ME) technique to analyse and study the dynamic characteristics of a Tubular Linear Switched Reluctance Stepping Motor (LSRSM). After the resolution of the non-linear electromagnetic equation governing the behaviour of the different materials of the motor using the nodal-based finite element method, this equation is then coupled to the mechanical equation firstly through the magnetic force computed by Maxwell stress tensor, and secondly by the modified flux distribution due to the moving part. Because of the precision required in the mobile part displacement and the very small air gap of stepping motors, the simulation of the movement is assured by the Macro-Element (ME) technique compared to other movement techniques that present many disadvantages. The validity of the developed model is verified through the comparison of the computed displacement of the LSRSM moving part with those given experimentally [2]. The Results shows satisfactory agreement. The obtained dynamic characteristics, particularly the starting magnetic force, are obtained by considering two values of the supplying currents.

关键词： Numerical Modeling Electromagnetic-Mechanical Phenomena Finite Element Movement Stepping motors

Static-torque Characteristics of Three-phase Hybrid(HB) Stepping motors and Influence of Way of Winding Connection on Operating Characteristics of motors of This Kind

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Journal of Harbin Institute of Technology(New Series) 1997年第4期4卷 59-62页

作者：刘宝廷郑萍崔淑梅

Ｓｔａｔｉｃ－ｔｏｒｑｕｅＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＴｈｒｅ－ｐｈａｓｅＨｙｂｒｉｄ（ＨＢ）ＳｔｅｐｐｉｎｇＭｏｔｏｒｓａｎｄＩｎｆｌｕｅｎｃｅｏｆＷａｙｏｆＷｉｎｄｉｎｇＣｏｎｎｅｃｔｉｏｎｏｎＯｐｅｒａｔ... 详细信息

Ｓｔａｔｉｃ－ｔｏｒｑｕｅＣｈａｒａｃｔｅｒｉｓｔｉｃｓｏｆＴｈｒｅ－ｐｈａｓｅＨｙｂｒｉｄ（ＨＢ）ＳｔｅｐｐｉｎｇＭｏｔｏｒｓａｎｄＩｎｆｌｕｅｎｃｅｏｆＷａｙｏｆＷｉｎｄｉｎｇＣｏｎｎｅｃｔｉｏｎｏｎＯｐｅｒａｔｉｎｇＣｈａｒａｃｔｅｒｉｓｔｉｃ...

关键词： Stepping motors torque characteristics winding connection

Fault Tolerant Neuro-Robust Position Control of DC motors

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Journal of Electromagnetic Analysis and Applications 2011年第10期3卷 412-415页

作者： Ran Zhang Marwan Bikdash 不详

DC motors are widely used in industry such as mechanics, robotics, and aerospace engineering. In this paper, we present a high performance control method for position control of DC motors. Fault-tolerant control model are also addressed to combine with neuro-robust control approach. It is shown that with the proposed control algorithms, external disturbances and coupled dynamics inherent in the system are effectively compensated using neural network unit in which no analytical estimation on the upper bound of the reconstruction error and uncertainties is needed. Simulations on various flight conditions also confirm the effectiveness of the proposed methods.

关键词： Fault-Tolerant Neuro-Robust Position Control DC motors

英雄识英雄——成龙与MITSUBISHI motors

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汽车之友 2007年第18期 76-77页

日前，MITSUBISHI motors宣布聘请世界著名影星成龙先生作为其2007年在中国市场的形象代言人。成龙将出现在电视、报纸、杂志等广告宣传中，参加各种活动，共同制作限量版车型等，与MITSUBISHI motors在各种领域开展合作。

关键词：成龙 MITSUBISHI motors 中国市场形象代言人汽车

“特斯拉杀手”创电动汽车最大规模IPO，Lucid motors估值240亿美金 B01

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“特斯拉杀手”创电动汽车最大规模IPO，Lucid Motors估值240亿美...

Investigation of a novel pyrogenic pulser in a laboratory motor

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作者：张凌霄

近日,据外媒报道,美国电动车初创企业Lucid motors与Churchill Capital IV(CCIV)达成协议,Lucid将通过与该公司合并的方式完成在纽交所的借壳上市。根据双方发布的联合声明,此次参与私募股权公司包括Lucid现有大股东沙特公共投资基金(P... 详细信息

近日,据外媒报道,美国电动车初创企业Lucid motors与Churchill Capital IV(CCIV)达成协议,Lucid将通过与该公司合并的方式完成在纽交所的借壳上市。根据双方发布的联合声明,此次参与私募股权公司包括Lucid现有大股东沙特公共投资基金(PIF)以及贝莱德、富达、富兰克林邓普顿

关键词：特斯拉 Lucid motors IPO 电动汽车

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Chinese Journal of Aeronautics 2020年第1期33卷 134-148页

作者： Roohollah TAHERINEZHAD Gholamreza ZAREPOUR Department of Mechanical Engineering University of GuilanRasht 51665-315Iran

In this paper,a novel pyrogenic pulser was designed both analytically and numerically and was evaluated with empirical *** motivation of this study was the need for active control of the aero acoustic pressure oscillations by injecting the secondary flow into the solid rocket ***,in brief,pyrotechnic and pyrogenic pulsers were introduced,and then analytical governing equations were presented in three transient,sinusoidal and Hercules *** order to understand the internal pressure of the pulsar and its plume length,the injection flow field was evaluated using the ANSYS-Fluent software with both k-ωSST and k-εRealizable models both at ambient and motor *** that,the design and manufacturing of the pulser hardware and the test process were ***,analytical,numerical and experimental results were *** results show that there is a good correlation between the transient analysis in theory and the numerical solution by the k-ωSST model and the empirical test *** addition,pyrogenic pulsers design depends on various parameters of motor and pulser charge performance *** quality of pulser charge bonding to its insulator and erosion of its throat path due to injection have an important role to obtain a desirable pulser mass flow rate and plume length.

关键词： Aero acoustic Pressure oscillation Pyrogenic pulsers Secondary injection Solid rocket motors