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8th International Conference on Computing and Artificial Intelligence, ICCAI 2022

作者： Liang, Yingjie Han, Yueying Jiang, Feng National Key Laboratory for Vessel Integrated Power System Technology Naval University of Engineering Wuhan China

ISBN: (纸本)9781450396110

With the rapid development of deep learning, the accuracy of object detection has greatly improved. But like the dark clouds in the clear sky, small objects detection is still a problem in computer vision. Due to low resolution, few pixels, limited information and rough outline, the features are difficult to extract, and training data is difficult to label. Around the problems and challenges in small object detection, we made an analysis and overview of the research progress and status of deep learning-based algorithms from one-stage and two-stage object detection methods. Then some techniques for small object detection are analysed from the aspects of feature enhancement, multi-scale prediction and detection network model. Finally, aiming at the problems and the development trend of machine vision, we make predictions and prospects for the application and development of small object detection in the future. © 2022 ACM.

关键词： Computer vision

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Study on PEEK/CF Composite Finite Element Model 26

Study on PEEK/CF Composite Finite Element Model

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26th International Conference on Electrical Machines and systems, ICEMS 2023

作者： Yang, Jing Su, Weiguo Wang, Dong Naval University of Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China Hubei East Lake New Power Co. Ltd. Wuhan China

ISBN: (纸本)9798350317589

The high speed motor will produce a large centrifugal force when rotating, so it is necessary to use special carbon fiber composite material or structure to ensure the strength of the rotor. Taking carbon fiber composite material as the research object, Johnson-Cook model was used to describe the mechanical behavior of PEEK material under the condition of hot forming. ABAQUS finite element software was used to establish the calculation model, and relevant experiments and research were carried out accordingly, which provided a new idea for the study of PEEK hot forming performance. © 2023 IEEE.

关键词： Carbon fibers

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Predictive Fuzzy Control Using Particle Swarm Optimization for Magnetic Levitation system 16th

Predictive Fuzzy Control Using Particle Swarm Optimization f...

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16th Annual Conference of China Electrotechnical Society, CES 2021

作者： Bu, Fanqi Xu, Jie College of National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan430033 China

ISBN: (纸本)9789811915277

The magnetic levitation system (MLS) has the characteristics of time-delay, open-loop unstable and non-linear. Considering the poor robustness and ability to tack ideal position of conventional algorithms, a predictive fuzzy proportional-integral-derivative (PID) with particle swarm optimization (PSO-PFPID) controller was proposed. With the recursive least squares (RLS) algorithm, a controlled auto-regressive integrated moving-average (CARIMA) model is identified on line and it serves for the predictive model of the generalized predictive control (GPC). Then the predicted optimal control law in the future time is served as the input of fuzzy PID (FPID). To enhance the dynamic and steady performance of the predictive fuzzy PID (PFPID) controller at the same time, the softening coefficient α and forgetting factor μ of the PFPID controller are globally optimized offline with the particle swarm optimization (PSO) algorithm. Finally, the maglev ball system is employed as the controlled object of the simulation and experiment and the mathematical model in balance points at the equilibrium point. Compared with PID, cascade GPC PID(PPID), simple PFPID, the PSO-PFPID controller has better robustness and make the controlled object stable in the case of mismatch. It can effectively adapt to system parameters changes. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Particle swarm optimization (PSO)

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MAGNETOSTRICTIVE VIBRATION SEPARATION AND EXPERIMENTAL RESEARCH ON MOTOR LAMINATED CORE 28

MAGNETOSTRICTIVE VIBRATION SEPARATION AND EXPERIMENTAL RESEA...

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28th International Congress on Sound and Vibration, ICSV 2022

作者： Zhang, Xianbiao Wang, Dong Chen, Junquan Wang, Xing Yi, Xinqiang National Key Laboratory for Vessel Integrated Power System Technology Naval University of Engineering Wuhan430033 China

ISBN: (纸本)9789811850707

As the major cause of noise in transformers and inductors, magnetostriction has been investigated extensively in non-rotating electric machines. In contrast to magnetostriction, the reluctance forces acting on the stator teeth are a major cause of noise emission in rotating electric machine. For rotating electric machines, magnetostriction is a potential cause of additional noise, and accurate magnetostriction data are hard to obtain. First, the simulation of vibration induced by reluctance forces has been investigated using 3D finite-element models. Next, the computation and test of the vibration specture caused by electromagnetism and magnetostriction effects, by example of an electromagnetic actuator with sinusoidal power supply. Moreover, two kinds current power supply are compared: fundamental exciting currents and third harmonic exciting currents with air-gap magnetic field density around 1.2 T. Compares the vibration acceleration spectra computed for reluctance forces as well as tested for both reluctance forces and magnetostriction. The finite-element predicted vibration acceleration by reluctance forces is compared with test results, where a relatively good agreement is achieved. It can be seen that the vibrations due to magnetostriction are considerably smaller than the effect due to reluctance forces. © International Institute of Acoustics and Vibration (IIAV), 2022.

关键词： Laminating

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INFLUENCE OF MOTOR AIR-GAP ECCENTRICITY ON THE VIBRATION OF ROTOR WITH ASYMMETRIC STIFFNESS 28

INFLUENCE OF MOTOR AIR-GAP ECCENTRICITY ON THE VIBRATION OF ...

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28th International Congress on Sound and Vibration, ICSV 2022

作者： Hu, Yuchao Wang, Xing Li, Wenyin Hu, Jinghua National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Hubei Province Wuhan430033 China

ISBN: (纸本)9789811850707

In motors, the electromagnetic forces and mechanical forces are usually considered as independent vibration sources, and their coupling mechanism is seldom investigated. In this paper, the influence of unbalanced magnetic pull (UMP) caused by motor air-gap eccentricity on mechanical force excitation of rotor is studied for a permanent magnet synchronous motors (PMSM). The components of electromagnetic forces in multiple pole-pairs motor with a static eccentricity in air-gap is firstly analyzed. Considering the mass eccentricity and asymmetric stiffness of rotor, a nonlinear dynamics model with UMP is established. Multi-scale method is used to solve the nonlinear equation. The results reveal that the component of double rotation frequency vibration (2X) occurs when considering asymmetric stiffness. However, the amplitude of 2X component corresponds to the UMP force. Experiments are carried out on a six pole-pairs permanent magnet synchronous motor. The result shows that the amplitude of 2X component has a positive correlation within small air-gap eccentricity, which verifies the analytical conclusions. © International Institute of Acoustics and Vibration (IIAV), 2022.

关键词： Stiffness

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Period Energy Method to Detect Demagnetization Failure of Surface Mounted Permanent Magnet Motor with Search Coil 16th

Period Energy Method to Detect Demagnetization Failure of Su...

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16th Annual Conference of China Electrotechnical Society, ACCES 2021

作者： huang, Wen Hu, Jinghua National Key Laboratory of Science and Technology on Vessel Integrated Power System No.717 Jiefang Avenue Qiaokou District Wuhan China

ISBN: (纸本)9789811915314

Permanent magnet synchronous motors are widely used in major fields such as aerospace, wind power generation, high-end manufacturing, national defense, and military industry due to its many advantages. The stability of permanent magnet materials will be affected by factors such as temperature, external magnetic field, acid-base corrosion, and manufacturing defects, resulting in uniform demagnetization or partial demagnetization failures. Demagnetization fault is a unique fault of permanent magnet motor. It will reduce operating efficiency, increase torque ripple, and deteriorate vibration performance. This paper studies the change of the "period energy" in search coil caused by demagnetization. When the permanent magnet is demagnetized, the asymmetry of the rotor magnetic field makes the "period energy" in the search coil no longer zero, and its amplitude proportional to the failure degree. The equivalent surface current method is used in the calculation of the air gap magnetic field due to its intuitive physical meaning and the advantages of calculation speed. Based on the acquisition of the air gap magnetic field, the induced voltage of the search coil is obtained based on the law of electromagnetic induction and the "period energy" is calculated to diagnose magnet’s fault. The comparison with the finite element and simulation results shows that the method proposed in this paper can effectively monitor the permanent magnet demagnetization failure and quantitatively evaluate the degree of loss of magnetization. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

关键词： Permanent magnets

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Lithium-ion Batteries RUL Prediction Based on Temporal Pattern Attention 15

Lithium-ion Batteries RUL Prediction Based on Temporal Patte...

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2022 15th International Conference on Computer and Electrical Engineering, ICCEE 2022

作者： Qin, Haochen Fan, Xuexin Fan, Yaxiang Wang, Ruitian Tian, Fengyuan National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering 717 Jiefang Avenue 430033 China

Accurate prediction of battery remaining useful life (RUL) under various operating conditions is essential for battery management systems to evaluate battery reliability, reduce the risk of battery usage and provide a rationale for battery maintenance. However, RUL prediction is a challenging problem since battery degradation is a nonlinear process and is influenced by external factors. In order to improve the prediction speed and accuracy, the research proposes a new Li-ion batteries RUL prediction method based on temporal pattern attention-based, which can take into account the influence of different variables for prediction. To model time-invariant patterns across multiple time steps, it combines a gated recurrent unit (GRU), a convolutional neural network, and an attention mechanism. Battery capacity, impedance and temperature are taken as input to train the model. Experiments are validated on public datasets and the results are compared with state of art methods. The experimental results show that the proposed method achieves the lowest MAE with 8.99, which proves the effectiveness of the method. © 2022 Published under licence by IOP Publishing Ltd.

关键词： Lithium-ion batteries

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Investigation on influence of gamma irradiation on piezoelectric and resonance characteristics of surface acoustic wave resonators 5

Investigation on influence of gamma irradiation on piezoelec...

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5th International Conference on Mechanical Engineering and Materials, ICMEM 2024

作者： Sun, Lei Peng, Bin Yang, Yuntao Sun, Zhaofeng Zhu, Jialiang Zhang, Wanli State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Chengdu China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of China Chengdu China

ISBN: (数字)9781510688971

ISBN: (纸本)9781510688964

In this work, an evaluation towards influence of high-dose gamma irradiation on surface acoustic wave (SAW) resonators, is reported. The single-port SAW resonators are fabricated using Lithium niobate (LiNbO3) and Catangasite (CTGS, Ca3TaGa3Si2O14) substrates, along respective cut directions of (0º, 38º, 0º) and (0º, 90º, 0º). Piezoelectric coefficient of substrates, and several main resonance parameters covering resonance frequency, amplitude of resonance peak in reflection coefficient, quality factor together with electromechanical coupling factor of manufactured SAW resonators are investigated, as suitable representatives of piezoelectric and resonance characteristics of SAW resonators. After exposure to gamma ray with a maximum dose of 250 kGy, substrates show insignificant variation not exceeding 6% in their piezoelectric coefficient. Meanwhile, resonance parameters of SAW resonators also alter slightly. Such excellent stability of these characteristics demonstrates credible irradiation hardness owned by both SAW resonators. Results in this study can provide supportive references for usage of LiNbO3 and CTGS-based SAW devices in harsh environments. © 2025 SPIE.

关键词： Gamma rays

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A High-power Self-interference Signal Cancellation Architecture Based on RF and Baseband Cancellation Cascade 10

A High-power Self-interference Signal Cancellation Architect...

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10th IEEE Joint International Information technology and Artificial Intelligence Conference, ITAIC 2022

作者： Luo, Hang Li, Yi Xing, Jinling Ge, Songhu He, Fangmin Meng, Jin Naval University of Engineering National Key Laboratory for Vessel Integrated Power System Technology Hubei Wuhan430033 China

ISBN: (数字)9781665422079

ISBN: (纸本)9781665422079

In this paper, a novel cancelling scheme based on orthogonal vector synthesis cancelling and baseband cancelling is proposed to solve the problem of high power common access self-interference(SI). First, the main interference is properly suppressed by the first stage of RF cancellation, and the high-power interference signal can reach the dynamic range requirements of the ADC. The second stage baseband cancellation technology is used to suppress the remaining SI signals and recover useful signals. The cancellation performance of high power SI signal is greatly improved by two-stage processing of autointerference signal. Compared with the single-stage cancellation structure, the RF circuit can deal with high-power SI signals, and because of the performance supplement of the sub-stage cancellation, the accuracy requirement of the first stage RF cancellation circuit device is greatly reduced. The second stage cancellation relies on high speed digital signal processing technology to ensure sufficient cancellation speed. The simulation model is established to verify the superior cancellation performance of the structure in high power SI signals. © 2022 IEEE.

关键词： Signal interference

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Research on current decoupling control of six-phase permanent magnet linear synchronous motor for electromagnetic launch

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International Journal of Mechanical system Dynamics 2021年第2期1卷 267-277页

作者： Xingfa Sun Jin Xu Junjie Zhu Department of Electrical Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power SystemNaval University of EngineeringWuhanChina

Six-phase permanent magnet linear synchronous motor(PMLSM)for electromagnetic launch(EML)system presents the characteristics of a high order,nonlinearity,multivariable,strong coupling,and nonperiodic transient operation in the synchronous rotating coordinate system,posing a great challenge to the dynamic response ability of the current *** research on current decoupling control(CDC)mainly focuses on cross decoupling within a three-phase system,even though there are neither decoupling methods for multiphase systems nor effective evaluation criteria for the decoupling and dynamic response *** this perspective,this paper first presents an equivalent reduced-order complex-matrix dynamic mathematical model of six-phase PMLSM and analyze its transient coupling characteristics during the process of ***,the CDC methods of six-phase PMLSM based on direct compensation and matrix diagonalization principles are realized,respectively,to accomplish the cross decoupling and back electromotive force decoupling within and between different three-phase ***,an all-round method is proposed,for the first time,to evaluate the decoupling performances and dynamic response performances of different CDC strategies for six-phase *** superiority of deviation decoupling regulator in decoupling performance and robustness are verified based on high-speed EML experimental platform of six-phase PMLSM.

关键词： complex-matrix mathematical model current decoupling control electromagnetic launch strong transient

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