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2009 Asia-Pacific power and Energy Engineering Conference, APPEEC 2009

作者： Wen-Hua, Hu Wei-Ming, Ma Chun-Xi, Liu Huazhong University of Science and Technology Wuhan 430074 China East China Jiaotong University Nanchang 330013 China National Key Laboratory for Vessel Integrated Power System Technology Naval University of Engineering Wuhan 430033 China

ISBN: (纸本)9781424424870

One of the important functions of three-phase inverter is to maintain the symmetric three-phase output voltage when the three-phase loads are unbalanced. Although the traditional symmetrical component decomposing and superimpose theory can keep the voltage balance through compensating the positive-, negative- and zero-sequence components of output voltage, however, this method is time-consuming and not suitable for control. Aiming at high power middle frequency inverter source, a Proportion + Resonant controller which ensured a balanced three phase output voltage under unbalanced load is proposed in this paper. The regulator was proved to be applicable to both three-phase three-wire system and three-phase four-wire system and developed two methods of realization. The simulation results verified that this method can suppressed effectively the output voltage distorted caused by the unbalanced load and attained a high quality voltage waveforms. © 2009 IEEE.

关键词： Controllers

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High-Performance Object Detection for Optical Remote Sensing Images with Lightweight Convolutional Neural Networks 22

High-Performance Object Detection for Optical Remote Sensing...

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22nd IEEE International Conference on High Performance Computing and Communications, 18th IEEE International Conference on Smart City and 6th IEEE International Conference on Data science and systems, HPCC-SmartCity-DSS 2020

作者： Liu, Jia Liu, Renhua Ren, Kaijun Li, Xiaoyong Xiang, Jianjian Qiu, Shaohua China University of Geosciences School of Computer Science Wuhan China National University of Defense Technology College of Meteorology and Oceanography Changsha China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

ISBN: (纸本)9781728176499

Convolutional neural network (CNN)-based object detection for optical remote sensing images has achieved higher accuracy compared with traditional detection methods with handcrafted features. However, the deep and large CNNs make it hard to be deployed in real-Time scenarios with limited computation, storage, power and bandwidth resources, for example, data processing onboard airborne, satellites and unmanned aerial vehicles for search and rescue. Therefore, in this paper we present a high-performance object detection approach for optical remote sensing images. Based on the widely used Faster R-CNN framework, we integrate state-of-The-Art lightweight CNNs as backbone to extract features, slim the heavy-head architecture of two-stage detector by reducing dimensions of features, and fine-Tune our models with NWPU VHR-10 optical remote sensing dataset. Besides, the multi-Threading for CPU and detection in batches for GPU are deployed to enhance the throughput of detectors and utilization of multi-core CPU and many-core GPU. Experiments show that our presented detection approach can significantly reduce the model size, computation complexity and detection time, while maintaining competitive accuracy. Specifically, the one with ShuffleNet-v2 and slimmed features has achieved a highest mean average precision of 94.39%, a lowest computational complexity of 18.97 Giga floating point operations, a highest detection speed of 90.10 frames per second (fps) for GPU and 3.07 fps for CPU, corresponding to speedups of 6.94X and 13.26X compared with the baseline on the benchmarked system, with a model size of 13.6 MB. Moreover, it further improves the efficiency and achieves 4.98 fps on CPU with 4 threads, and 200.24 fps on GPU with a batch size of 32. © 2020 IEEE.

关键词： Object detection

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Post-arc Transient Characteristics for DC Vacuum Circuit Breaker With Diode Connected in Series

Post-arc Transient Characteristics for DC Vacuum Circuit Bre...

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IEEE Conference on Energy Internet and Energy system Integration (EI2)

作者： Zhendong Peng Bo Li Xinle Sha Chenguang Yang Zhigang Ren Ship Integrated Power System Technology Key Laboratory Wuhan Institute of Marine Electric Propulsion Wuhan China

ISBN: (数字)9781728196060

ISBN: (纸本)9781728196077

Experimental investigations have been carried out on the rapid high current commutation interruption (CI) process of a $10\mathrm{k}\mathrm{V}$ DC vacuum circuit breaker (VCB). The VCB arc restriking and breaking failure phenomenon appeared frequently in $23\mathrm{k}\mathrm{A}$ CI tests with arc current fall rate of about $300\mathrm{A}/\mu \mathrm{s}$ for a single VCB, while the VCB CI reliability has been improved a lot under the same conditions with diode connected in series. After a detailed analysis of the vacuum gap (VG) post-arc transient characteristics, it was found that it lasted about $450\mu \mathrm{s}$ before the VG finishing the ion sheath development for the single VCB in the post-arc stage. Meanwhile, the VG electric field intensity (EFI) and power density (PD) would quickly rise to the peak values of $12\mathrm{M}\mathrm{V}/\mathrm{m}$ and $45\mathrm{M}\mathrm{W}/\mathrm{m}^{2}$ separately in about $1\mu \mathrm{s}$ after the arc zero-crossing. As a result, the VG electrical or thermal breakdown were very prone to come out when the plasma concentration was still high in the sheath development stage. With the diode in series, the VG power injection path was cut off effectively by the diode reverse blocking, the initial transient recovery voltage rising very fast would be avoid and the plasma concentration was promoted to decay significantly, by which both the EFI and PD were decreased greatly when the VG began to get insulation recovery in the post-arc phase. Under the most extreme condition that the VG started to build dielectric strength at the end of the diode reverse blocking, the simulation results revealed the EFI and PD peak values were substantially reduced to $130\mathrm{k}\mathrm{V}/\mathrm{m}$ and $1.4\mathrm{k}\mathrm{W}/\mathrm{m}^{2}$ respectively and delayed for about $30\mu \mathrm{s}$, which were very beneficial to reduce the VG breakdown probability and improve the dielectric recovery performance in the post-arc transient.

关键词： Insulation Circuit breakers Snubbers Plasmas Dielectrics Transient analysis integrated circuit reliability

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A speed sensorless control strategy for a dual three-phase linear induction motor based on SMFEKF

A speed sensorless control strategy for a dual three-phase l...

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CSAA/IET International Conference on Aircraft Utility systems, AUS 2018

作者： Sun, Xingfa Nie, Ziling Zhu, Junjie Han, Yi Ye, Weiwei Sun, Jun Wu, Yanhao National Key Laboratory of Science and Technology on Vessel Integrated Power System Navy University of Engineering Wuhan430033 China College of Electrical Engineering Navy University of Engineering Wuhan430033 China

ISBN: (纸本)9781785617911

The speed sensorless control of linear motors is an important research in the field of electric drive. According to the dual-αβ mathematical model of a dual three-phase linear induction motor (LIM), this paper presents an equivalent single-αβ mathematical model and the fourth-order state equation of the dual three-phase LIM that have been derived from variable substitution for the purpose of estimating the rotor speed based on the extended kalman filter. Because the extended kalman filter algorithm is poor in estimation performance when the system state changes suddenly, a method of rotor speed estimation is proposed on the basis of suboptimal multiple fading extended kalman filter. The online adaptive regulation of the prediction error covariance matrix leads to an improvement on the algorithm for the system robustness. The use of the control strategy for a secondary magnetic field-oriented average torque current can keep the torque components of the dual three-phase currents constant and reduce the imbalance of the currents The simulation and experimental results show that the speed sensorless control strategy is superior to the conventional extended kalman filter algorithm in the accuracy of speed estimation. © 2018 IET Conference Publications. All rights reserved.

关键词： Electric drives

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Modeling of hybrid DC fuse based on piecewise fitting 22

Modeling of hybrid DC fuse based on piecewise fitting

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22nd International Symposium on High Voltage Engineering, ISH 2021

作者： Liu, Shaopeng Ji, Feng Li, Siguang Sun, Wen National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan430033 China College of Electrical Engineering Naval University of Engineering Wuhan430033 China

ISBN: (纸本)9781839536052

As a current limiting device, Hybird DC fuse can be used to limit the short-circuit current of the system, In order to precheck the current limiting capability, a simulation model of fuse needs to be established. However, the existing model is relatively complex, and there is no mature model that can be directly called in the existing simulation software. Therefore, this paper designs a piecewise fitting method based on the arcing test data of fuse to describe the whole process of arc drawing. First, considering the influence of resonance and other factors in the test data acquisition of the fuse breaking, the ripple is mixed, and a stepwise filtering algorithm is proposed;Then, according to the degree of fluctuation of the arcing curve, the piecewise points are selected using the normalized curvature criterion and the normalized residual norm criterion respectively, which solves the problem that the piecewise points rely on the designer's practical experience;Finally, according to the results of piecewise fitting, a fuse model of arcing resistance changing with time is constructed in PSCAD, and the simulation verifies the effectiveness of the method used. © 2021 The Institution of Engineering and technology.

关键词： Data acquisition

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Design of lossless snubber circuit for phase-shifted full-bridge converter

Design of lossless snubber circuit for phase-shifted full-br...

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2020 International Conference on Applied Physics and Computing, ICAPC 2020

作者： Ji, Shengxian Jie, Guisheng Gao, Shan Wang, Hengli Wang, Ruitian Liu, Xiaohu National key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan430033 China College of Electrical Engineering Naval University of Engineering Wuhan430033 China

In the phase-shifted full-bridge circuit, the voltage spike caused by the hard turn-off of the switch tube increases the voltage stress of the switching device. Due to the existence of energy-consuming components such as resistance in the traditional absorption circuit, the efficiency is not always high. Based on the RCD snubber circuit, a low-loss absorption circuit is designed in this paper. This circuit absorbs voltage spikes through an absorption capacitor, and then slowly releases energy through an oscillating circuit consisting of current-limiting inductance, stray inductance, and absorption capacitance. The current-limiting inductance reduces the current stress of the blocking diode effectively, which can be achieved with the absorption not being affected and the power loss being reduced. Finally, the absorption effect and energy loss of the new low-loss absorption circuit and the commonly used RCD circuit were simulated and compared in PSpice software, and verified its feasibility. © 2020 Institute of Physics Publishing. All rights reserved.

关键词： Capacitance

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Intelligent recognition and information extraction of radar complex jamming based on time-frequency features

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Journal of systems Engineering and Electronics 2024年第5期35卷 1148-1166页

作者： PENG Ruihui WU Xingrui WANG Guohong SUN Dianxing YANG Zhong LI Hongwen College of Information and Communication Engineering Harbin Engineering UniversityHarbin 150001China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China Information Fusion Research Institute Naval Aeronautical UniversityYantai 264001China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of EngineeringWuhan 430033China

In modern war,radar countermeasure is becoming increasingly fierce,and the enemy jamming time and pattern are changing more *** is challenging for the radar to efficiently identify jamming and obtain precise parameter information,particularly in low signal-to-noise ratio(SNR)*** this paper,an approach to intelligent recognition and complex jamming parameter estimate based on joint time-frequency distribution features is proposed to address this challenging ***,a joint algorithm based on YOLOv5 convolutional neural networks(CNNs)is proposed,which is used to achieve the jamming signal classification and preliminary parameter ***,an accurate jamming key parameters estimation algorithm is constructed by comprehensively utilizing chi-square statistical test,feature region search,position regression,spectrum interpolation,etc.,which realizes the accurate estimation of jamming carrier frequency,relative delay,Doppler frequency shift,and other ***,the approach has improved performance for complex jamming recognition and parameter estimation under low SNR,and the recognition rate can reach 98%under−15 dB SNR,according to simulation and real data verification results.

关键词： complex jamming recognition time frequency feature convolutional neural network(CNN) parameter estimation

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Research on novel high torque density transverse-flux permanent magnet motor

Research on novel high torque density transverse-flux perman...

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International Conference on Electrical Machines and systems (ICEMS)

作者： Changpeng Lv Lichun Zhang Yongxiang Xu Yang Liu Science and Technology on Ship Integrated Power System Technology Wuhan China School of Electric Engineering and Automation Harbin Institute of Technology Harbin China

ISBN: (纸本)9781728133997

A new transverse flux permanent magnet motor(TFPMM) with skewed PMs and shared-border pole stator is presented in the paper, which can make full use of laminations instead of soft magnetic composite (SMC) material. This new TFPMM also has a higher torque density by advantageously utilizing the laminations and taking full advantage of the radial space. To clarify the distribution of inner magnetic field and the optimal design rule for the new TFPMM, the Maxwell 3D finite element method(FEM) has to be adopted, and a simplified model for analysis and optimizations is presented. A prototype scheme is presented. The theoretical analysis was verified by finite element analysis and prototype test results.

关键词： Stator cores Magnetic flux Magnetic cores Rotors Air gaps Permanent magnet motors Prototypes

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Diagnosis of Inter-Turn Short Circuit Fault of AMB Based on Forgetting Factor Recursive Least Square Algorithm 8

Diagnosis of Inter-Turn Short Circuit Fault of AMB Based on ...

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8th International Conference on Reliability of Electrical Products and Electrical Contacts, ICREPEC 2022

作者： Li, Henghui Wu, Lijian Su, Zhenzhong Chen, Junquan Lyu, Zekai Niu, Feng College of Electrical Engineering Zhejiang University Hangzhou China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin China

ISBN: (纸本)9789881532374

Fault diagnosis is one of the most important ways to improve the reliability of an active magnetic bearing (AMB) system. The inter-turn short circuit (ITSC) fault of an AMB may lead to catastrophic consequence such as rotor impact and winding open circuit. Hence, it is vital to diagnose the ITSC fault in real-time. To diagnosis the ITSC fault of AMB, a model of the AMB with ITSC fault is established in this paper. A method is proposed to extract the fault feature utilizing the forgetting factor recursive least square (FFRLS) algorithm. Furthermore, a compensation method based on look-up table is introduced to improve the robustness of the proposed method to the eccentricity of the rotor. The effectiveness of proposed method is verified by experiments. © ICREPEC *** rights reserved

关键词： Failure analysis

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Anomaly Detection-Oriented High-Frequency Signal Storage for Diesel Engines 4

Anomaly Detection-Oriented High-Frequency Signal Storage for...

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4th IEEE International Conference on Computer and Communication Engineering technology, CCET 2021

作者： Huang, He Xu, Bailing Luo, Hao Zhuang, Haoran Liu, Xuewei Ma, Liyong Naval University of Engineering National Key Laboratory for Vessel Integrated Power System Technology Wuhan China Shanghai Marine Diesel Engine Research Institute Shanghai China School of Information Science and Engineering Harbin Institute of Technology Weihai China

ISBN: (纸本)9781665438902

Marine diesel engine has been the main power of civil ships, small and medium-sized ships and conventional submarines. Anomaly detection on diesel engines is very important for the safety of marine systems. Diesel engine anomaly detection requires access to a large number of high-frequency signals. How to store these signals to support anomaly detection applications is currently rarely studied. This article discusses the design of high-frequency signal storage systems that provide data support for intelligent anomaly detection systems. It mainly focuses the design of database system and file system for high-frequency signal storage requirements of diesel engines. The actual operation shows that the system designed in this paper can support the storage of high-frequency signals and the deployment of anomaly detection applications. © 2021 IEEE.

关键词： Diesel engines

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