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2020 3rd International Symposium on power Electronics and Control Engineering, ISPECE 2020

作者： Ma, Xiao Huang, Yongle Luo, Yifei National Key Laboratory of Science and Technology on Vessel Integrated Power System China

Considering overload working conditions in electromagnetic emission, the paper presents a simulation of IGBT turn-off under large current and high temperature. Numerous simulation result is received under a specific test circuit. Boundary conditions for temperature, current and starry inductance are obtained under a set of temperature criterion. Further analysis proves that after temperature reaches the criterion, high current density path swiftly extends from local area to a vertical current path throughout the cells. This method for IGBT theoretical boundary is useful for similar projects or working conditions. © Published under licence by IOP Publishing Ltd.

关键词： Insulated gate bipolar transistors (IGBT)

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An RNN-EKF Observer for Time Delay of Large-Scale Motor Control system 10

An RNN-EKF Observer for Time Delay of Large-Scale Motor Cont...

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

作者： Song, Lin Nie, Ziling Xu, Jie Song, Zelin Li, Huayu Naval University of Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China Taiyuan University of Technology of Shanxi Province Taiyuan China

ISBN: (数字)9781665422079

ISBN: (纸本)9781665422079

For a large-scale motor control system with non-negligible time delay, a Recursive Neural Network- Extended Kalman Filter (RNN-EKF) observer is proposed to estimate the flux and reduce the disturbance caused by the time delay. In this paper, the motor model is designed to simulate the actual operating conditions: the motor resistance varies with temperature and time delay is considered in the current loop. The proposed observer combines the RNN with EKF algorithm, aiming at reducing the error between the observed flux and the actual flux by training weight coefficients of the neural network. Simulation results show that the proposed observer owns good static and transient control performance. In addition, the effect of the unknown time delay is effectively reduced. © 2022 IEEE.

关键词： Time delay

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Optically transparent Millimeter-Wave metasurface for frequency-spatial multiplexed holographic imaging 12

Optically transparent Millimeter-Wave metasurface for freque...

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12th IEEE Asia-Pacific Conference on Antennas and Propagation, APCAP 2024

作者： Zhang, Zhiyun Zhang, Guang Zhou, Yulong Li, Sijia Tian, Jianghao Guo, Zexu Cao, Xiangyu Air Force Engineering University Information and Navigation College Xi'an710077 China Shaanxi Changling Electronic Technology Co. Ltd. Baoji721006 China Pla Naval University of Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan430033 China

ISBN: (纸本)9798350351019

Restricted by the physical properties of materials, most traditional electromagnetic (EM) metasurfaces cannot achieve transparent stealth in visible spectrum. Although some metasurfaces for holography have been designed, there is no standard method for evaluating the advancement of wavefront manipulation, metasurface design, and algorithms. Here, a novel full space control the complex amplitude of a metasurface with optical transparency (OT) is presented in the millimeter-wave (mmWave) band. Through frequency-multiplexing, two distinct holographic images 'HOLO' and 'GRAM' with high quality are designed, achieving signal-to-noise ratios (SNR) of 14.6 dB and 14.4 dB, respectively. The 64 × 64 bi-layered metasurface is composed of glass and PET substrates and three silver mesh layers. By changing the opening size and rotating angle of split rings, phase and amplitude modulations are simultaneously and independently realized at 26.6 GHz and 44.0 GHz. © 2024 IEEE.

关键词： Microwave holography

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A fast positioning method of navigation receiver assisted by Doppler information

A fast positioning method of navigation receiver assisted by...

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第十四届中国卫星导航年会

作者： Yinyin Tang Junyong Lu Junhong Feng Kai Li National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering

In order to shorten the time to first fix(TTFF) of the satellite receiver,a fast positioning method using both carrier and pseudo code observation is ***,use the Doppler information acquired by the carrier tracking loop to reduce the a priori time accuracy to 100 ***,use the code phase acquired by pseudo-code tracking loop,and use the five-state equation to solve the receiver *** this way,positioning can be achieved before frame synchronization and bit *** simulation and test results show that positioning can be achieved within 1 second through Beidou/GPS dual system in the global or BeiDou alone in the Asia-Pacific region,when the a priori position accuracy is less than 10 km and the a priori time accuracy is less than 2 hours.

关键词： Time to First Fix Navigation Receiver Fast Positioning Doppler Information Code Phase

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Few-Shot Gearbox Fault Diagnosis Based on Semi-Supervised Prototypical Network and Contrastive Learning

Few-Shot Gearbox Fault Diagnosis Based on Semi-Supervised Pr...

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2023 China Automation Congress, CAC 2023

作者： Cheng, Shulie Liang, Yingjie Ping, Zuowei Liao, Xuechao Wang, Maolin Zhang, Yong School of Information Science and Engineering Wuhan University of Science and Technology Wuhan China Naval University of Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China School of Computer Science and Technology Wuhan University of Science and Technology Wuhan China School of Artificial Intelligence and Automation Huazhong University of Science and Technology Wuhan China

ISBN: (纸本)9798350303759

Due to the scarcity of labeled faulty data in industrial practice, fault diagnosis models often face challenges related to overfitting and limited accuracy. This article introduces a novel solution to tackle the problem - a fault diagnosis method that leverages a combination of a semi-supervised prototype network and contrastive learning. Firstly, a limited number of labeled samples is employed to construct pairs of positive and negative samples. And the training method of contrastive learning is used to provide appropriate initial parameters for the autoencoder. Secondly, the autoencoder is employed as a feature mapping function within the prototype network and obtains the prototype using a limited number of labeled samples. Finally, a prototype refinement method fine-tunes the prototype through unlabeled data, reducing the impact of anomalous data and obtaining a more stable and accurate prototype. The effectiveness of the proposed method is evaluated using gearbox data as a validation dataset. Through comparative analysis with other methods, the results demonstrate that the proposed approach achieves superior diagnostic accuracy. © 2023 IEEE.

关键词： Failure analysis

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Analysis of Electromagnetic Characteristics of a Novel Toroidal Acceleration Linear Motor

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CES Transactions on Electrical Machines and systems 2022年第2期6卷 113-117页

作者： Zhentian Liu Qiaopeng Zhou Weichao Li National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430000China School of Electrical and Electronic Engineering Naval University of EngineeringWuhan 430000China

A high thrust density linear motor,which adopts a novel toroidal structure,applying to load acceleration in confined space is *** basic structure of the toroidal acceleration permanent magnet synchronous linear motor(TA-PMLSM)is depicted,both with its parameters *** main characteristics such as air gap magnetic density and electromagnetic thrust are discussed by establishing the electromagnetic field equation in the cylindrical coordinate *** simulation comparison between the Halbach permanent magnet array and the classical radial one is also made to get a higher density of the magnetic and electromagnetic *** with the conventional radial permanent magnet array,results show that the amplitude of back EMF of ring motor under the action of Halbach permanent magnet array has a better sinusoidal,the magnetic density of the air gap increases by 1.3 times,the thrust density increases by 1.42 times,and the main harmonic content of the two referred physical quantity decreases significantly.

关键词： Toroidal motor Linear motor Electromagnetic field analysis.

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Line width mathematical model in fused deposition modelling for precision manufacturing 2

Line width mathematical model in fused deposition modelling ...

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2020 2nd International Conference on power, Energy and Electrical Engineering, PEEE 2020

作者： Jiang, J.C. Xu, Xinghua Rui, Wanzhi Jia, Zhengrong Ping, Zuowei National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China

Additive manufacturing is becoming increasingly popular because of its unique advantages, especially fused deposition modelling (FDM) which has been widely used due to its simplicity and comparatively low price. However, in current FDM processes, it is difficult to fabricate parts with highly accurate dimensions. One of the reasons is due to the slicing process of 3D models. Current slicing software divides the parts into layers and then lines (paths) based on a fixed value. However, in a real printing process, the printed line width will change when the process parameters are set in different values. The various printed widths may result in inaccuracy of printed dimensions of parts if using a fixed value for slicing. In this paper, a mathematical model is proposed to predict the printed line width in different layer heights. Based on this model, a method is proposed for calculating the optimal width value for slicing 3D parts. In the future, the proposed mathematical model can be integrated into slicing software to slice 3D models for precision additive manufacturing. © The Authors, published by EDP sciences, 2021.

关键词： Fused Deposition Modeling

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VIBRATION PREDICTION UNDER ELECTROMAGNETIC FORCE EXCITATION OF A THREE-PHASE INDUCTION MOTOR USING HYBRID FE-SEA METHOD 28

VIBRATION PREDICTION UNDER ELECTROMAGNETIC FORCE EXCITATION ...

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28th International Congress on Sound and Vibration, ICSV 2022

作者： Wang, Xing Li, Xuhan Zhang, Xianbiao Su, Wu National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Hubei Province Wuhan430033 China Unit 91697 of PLA China

ISBN: (纸本)9789811850707

In this paper hybrid FE-SEA method is used to model an 11kw three phase inductor motor. The whole FE-SEA model of the motor is built form commercial software VA One, while the internal loss factors are obtained from ESEA using hammer excitations. Vibration tests are also carried out on the whole motor when the motor is running at rated speed. Comparison of the vibration energy level differences between simulation and experiments shows large difference in low frequency due to low modal density. However, above 1 kHz FE-SEA model has good agreement with experiment, which verifies the modeling method. Finally, electromagnetic forces on each teeth are calculated in Ansys Maxwell and applied in the FE-SEA model. The predicted vibration responses and measurements show similar trends within 7dB differences. This work expands the application of hybrid FE-SEA method onto the motor vibration. © International Institute of Acoustics and Vibration (IIAV), 2022.

关键词： Electric excitation

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Research on Lfp Battery Balancing Strategy for the Hybrid Energy Storage system

SSRN

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SSRN 2024年

作者： Zhou, Ren Lu, Junyong Wu, Yiting Liu, Yingquan Yan, Kangwei National Key Laboratory of Electromagnetic Energy Naval University of Engineering Wuhan430033 China National Key Laboratory of Science and Technology on Vessel Integrated Power System China

For the problem of consistency decline in the long-term use of battery packs for the hybrid energy storage system, a dynamic timing adjustment balancing strategy is proposed based on the charge-discharge topology. Compared with the traditional balancing strategy, the dynamic timing adjustment balance strategy is more suitable for the transient high-frequency pulse and high-power output of the hybrid energy storage system. It gives full play to the pulse output adjustment function of the integrated charge-discharge topology. The advantages of the strategy include improving the balance between the battery packs, prolonging the service life of the battery packs, and improving the continuous work capability of the system. Combined with the work condition of the hybrid energy storage system, the balance control model is established, and cycle charge-discharge test platform of battery packs is built. The effectiveness and advantage of the balance strategy of dynamic timing adjustment is verified by the experiment and simulation. © 2024, The Authors. All rights reserved.

关键词： Topology

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Research on Temperature Rise and Heat Dissipation of Wireless power Transfer

Research on Temperature Rise and Heat Dissipation of Wireles...

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2022 International Conference on power Energy systems and Applications, ICoPESA 2022

作者： Li, Da Wu, Xusheng Gao, Wei Gao, Jianxin Naval University of Engineering School of Electrical Engineering Wuhan China Naval University of Engineering National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China

ISBN: (纸本)9781665410977

The magnetic coupler is a crucial part of the IPT system to achieve high-efficiency energy transmission. The heating loss of the magnetic coupler during operation causes the coil's temperature to rise, affecting the IPT system's operational stability. In this paper, the circuit and magnetic field model of the coupler are established. The heating mechanism of the coil, iron core and aluminum shielding plate in the coupler is studied. Furthermore, the temperature distribution of each component is given after running for 30 minutes. The temperature rise of each part of the coupler was measured, and the coil temperature was the highest. Through the thermal field simulation of the magnetic coupler, the temperature rise of each part of the magnetic coupler in the operation of the wireless power transmission system can be optimized. © 2022 IEEE.

关键词： Temperature distribution

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