检索结果-南通市图书馆

Dynamic neighborhood genetic learning particle swarm optimization for high-power-density electric propulsion motor

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2022年第12期35卷 253-265页

作者： jinquan xu Huapeng LIN Hong GUO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Ningbo Institute of Technology Beihang UniversityNingbo 315800China

To maximize the power density of the electric propulsion motor in aerospace application,this paper proposes a novel Dynamic Neighborhood Genetic Learning Particle Swarm Optimization(DNGL-PSO)for the motor design,which can deal with the insufficient population diversity and non-global optimal solution *** DNGL-PSO framework is composed of the dynamic neighborhood module and the particle update *** improve the population diversity,the dynamic neighborhood strategy is first proposed,which combines the local neighborhood exemplar generation mechanism and the shuffling *** local neighborhood exemplar generation mechanism enlarges the search range of the algorithm in the solution space,thus obtaining highquality ***,when the global optimal solution cannot update its fitness value,the shuffling mechanism module is triggered to dynamically change the local neighborhood *** roulette wheel selection operator is introduced into the shuffling mechanism to ensure that particles with larger fitness value are selected with a higher probability and remain in the local ***,the global learning based particle update approach is proposed,which can achieve a good balance between the expansion of the search range in the early stage and the acceleration of local convergence in the later ***,the optimization design of the electric propulsion motor is conducted to verify the effectiveness of the proposed *** simulation results show that the proposed DNGL-PSO has excellent adaptability,optimization efficiency and global optimization capability,while the optimized electric propulsion motor has a high power density of 5.207 kW/kg with the efficiency of 96.12%.

关键词： Dynamic Neighborhood Genetic Learning Particle Swarm Optimization(DNGL-PSO) Permanent magnet synchronous motor Power density Efficiency of motor Electric propulsion motor

Design and analysis of a novel hybrid cooling method of high-speed high-power permanent magnet assisted synchronous reluctance starter/generator in aviation applications

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第3期36卷 285-302页

作者： Hong GUO xu HE jinquan xu Wei TIAN Xiaofeng DING Laicai JU Dehong LI School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100083China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing 100083China Ningbo Innovation Research Institute Ningbo 315800China School of Electrical and Information Engineering Jiangsu UniversityZhenjiang 212013China Beijing Shuguang Aviation Electric Co.LTD Beijing 101300China Aviation Industry Helicopter Design and Research Institute Jingdezhen 333001China

To improve the heat dissipation performance,this paper proposes a novel hybrid cooling method for high-speed high-power Permanent Magnet assisted Synchronous Reluctance Starter/Generator(PMa Syn R S/G)in aerospace *** hybrid cooling structure with oil circulation in the housing,oil spray at winding ends and rotor end surface is firstly proposed for the PMa Syn R S/*** the accurate loss calculation of the PMa Syn R S/G is proposed,which includes air gap friction loss under oil spray cooling,copper loss,stator and rotor core loss,permanent magnet eddy current loss and bearing *** parameter sensitivity analysis of the hybrid cooling structure is proposed,while the equivalent thermal network model of the PMa Syn R S/G is established considering the uneven spraying at the winding ***,the effectiveness of the proposed hybrid cooling method is demonstrated on a 40 k W/24000 r/min PMa Syn R S/G experimental platform.

关键词： Air gap friction loss Oil spray cooling Permanent magnet assisted synchronous reluctance starter/generator Thermal analysis Thermal network model

Modeling and analysis of oil frictional loss in wet-type permanent magnet synchronous motor for aerospace electro-hydrostatic actuator

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2023年第11期36卷 328-341页

作者： jinquan xu Wenbo JIN Hong GUO Tian YU Wenhu FAN Zongxia JIAO School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Ningbo Institute of Technology Beihang UniversityNingbo 315800China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

To improve the power density and simplify the seal structure,the Wet-Type Permanent Magnet Synchronous Motor(WTPMSM)technique has been applied to aerospace Electro-Hydrostatic Actuators(EHA).In a WTPMSM,the stator and the rotor are both immersed in the aviation hydraulic *** the heat dissipation performance of the WTPMSM can be enhanced,the aviation hydraulic oil will cost an extra oil frictional loss in the narrow airgap of the *** paper proposes an accurate oil frictional loss model for the WTPMSM,in which the wide speed range(0–20 kr/min)and the narrowness of the airgap(0.5–1.5 mm)are its ***,the mechanism of the oil frictional loss in the airgap of the WTPMSM is *** an accurate oil frictional loss model is proposed considering the nonlinear influence caused by the Taylor ***,the influence of motor dimensions on oil frictional loss is ***,the proposed oil frictional loss model is verified by experiments,which provides a guideline for engineers to follow in the WTPMSM design.

关键词： Electro-hydrostatic actuator Motor dimensions Oil frictional loss Taylor vortex Wet-type permanent magnet synchronous motor

Interface models for thin interfacial layers

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2016年第6期37卷 707-724页

作者： Xiaojing CAI jinquan xu School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong University

There have already been several interface models for the analyses of thin interfacial layers in bonded materials. To distinguish their corresponding advantages or limitations, a comparative study is carried out, and a new constitutive-based interface model is proposed. Through numerical examinations, the limitations of typical models are clarified. It is found that the new interface model is an efficient and accurate model, by which both the traction and the displacement jumps across the modelled interface with the thickness of zero are allowed, and the stresses within the interracial layer can also be analyzed.

关键词： bonding interface model interfacial layer

Fault tolerant control with torque limitation based on fault mode for ten-phase permanent magnet synchronous motor

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2015年第5期28卷 1464-1475页

作者： Guo Hong xu jinquan School of Automation Science and Electrical Engineering Beihang University

This paper proposes a novel fault tolerant control with torque limitation based on the fault mode for the ten-phase permanent magnet synchronous motor （PMSM） under various open-circuit and short-circuit fault conditions, which includes the optimal torque control and the torque limitation control based on the fault mode. The optimal torque control is adopted to guarantee the ripple-free electromagnetic torque operation for the ten-phase motor system under the post-fault condition. Furthermore, we systematically analyze the load capacity of the ten-phase motor system under different fault modes. And a torque limitation control approach based on the fault mode is proposed, which was not available earlier. This approach is able to ensure the safety operation of the faulted motor system in long operating time without causing the overheat fault. The simulation result confirms that the proposed fault tolerant control for the ten-phase motor system is able to guarantee the ripple-free electromagnetic torque and the safety operation in long operating time under the normal and fault conditions.

关键词： Fault mode Fault tolerant Optimal torque control Permanent magnet motorTorque limitation

孔雀绿-PVA-磷钼酸铵分光光度法测定无铅锡基焊料中磷含量

在线全文

学校读者我要写书评

暂无评论

湖南有色金属 2024年第4期40卷 109-114页

作者：李丽段泽平韩红兰孙彪许金泉黄慧兰云南锡业新材料有限公司云南昆明650500

文章提出了孔雀绿-PVA-磷钼酸铵以三元络合物体系测定无铅锡基焊料中磷的方法,且能稳定存在于含有聚乙烯醇的水溶液中。缔合物最大吸收峰值位于600 nm波长处,波尔吸收系数ε=8.27×10^(4)L/mol·cm。线性回归方程为y=9.6731x-0.0761,相... 详细信息

文章提出了孔雀绿-PVA-磷钼酸铵以三元络合物体系测定无铅锡基焊料中磷的方法,且能稳定存在于含有聚乙烯醇的水溶液中。缔合物最大吸收峰值位于600 nm波长处,波尔吸收系数ε=8.27×10^(4)L/mol·cm。线性回归方程为y=9.6731x-0.0761,相关系数为0.9995,25 mL溶液中磷质量在1~6μg范围内符合Lambert-Beer定律。测定无铅焊料中磷含量相对标准偏差0.80%~2.95%(n=11),加标回收率在96.59%~104.45%。优化样品前处理方式,缩短了样品前处理时间。该法显色酸度范围宽、共存离子干扰性小、选择性好、显色稳定时间长,准确度较高,易于操作。

关键词：磷含量孔雀绿 PVA 分光光度法无铅焊料

A novel fault tolerant permanent magnet synchronous motor with improved optimal torque control for aerospace application

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2015年第2期28卷 535-544页

作者： Guo Hong xu jinquan Kuang Xiaolin School of Automation Science and Electrical Engineering Beihang University

Improving fault tolerant performance of permanent magnet synchronous motor has always been the central issue of the electrically supplied actuator for aerospace application. In this paper, a novel fault tolerant permanent magnet synchronous motor is proposed, which is character- ized by two stators and two rotors on the same shaft with a circumferential displacement of mechanical angle of 4.5°. It helps to reduce the cogging torque. Each segment of the stator and the rotor can be considered as an 8-pole/10-slot five-phase permanent magnet synchronous motor with concentrated, single-layer and alternate teeth wound winding, which enhance the fault isola- tion capacity of the motor. Furthermore, the motor has high phase inductance to restrain the short-circuit current. In addition, an improved optimal torque control strategy is proposed to make the motor work well under the open-circuit fault and short-circuit fault conditions. Simulation and experiment results show that the proposed fault tolerant motor system has excellent fault tolerant capacity, which is able to operate continuously under the third open-circuit fault and second short- circuit fault condition without system performance degradation, which was not available earlier.

关键词： Actuator Fault isolation Fault tolerant Optimal torque control Permanent magnet moto

Research on a six-phase permanent magnet synchronous motor system at dual-redundant and fault tolerant modes in aviation application

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2017年第4期30卷 1548-1560页

作者： Xiaolin KUANG Hong GUO jinquan xu Tong ZHOU School of Automation Science and Electrical Engineering Beihang University Beij'ing 100083 China

With the development of more/all electrical aircraft technology, an electro-mechanical actuator（EMA） is more and more used in an aircraft actuation system. The motor system, as the crucial part of an EMA, usually adopts the redundancy technology or fault tolerance technology to improve the reliability. To compare the performances of these two motor systems, a 10-pole/12-slot six-phase permanent magnet synchronous motor（PMSM） is designed with the concentrated single-layer winding, which is able to operate at dual-redundant and fault tolerant ***, the position servo performances of the six-phase PMSM at dual-redundant and fault tolerant modes are analyzed, including the normal and fault conditions. In addition, a variable structure proportional-integral-derivative（PID） control strategy is proposed to solve the performance degradation problem caused by phase current saturation. Simulation and experimental results show that the fault tolerant PMSM has a better position servo performance than the dual-redundant PMSM, and the variable structure PID control strategy is able to improve the performance due to phase current saturation.

关键词： Electro-mechanical actua tors Fault tolerant Permanent magnet syn chronous motor Redundancy Variable structure PID control

METTL1 promotes colorectal cancer cell proliferation by attenuating CHEK2-induced G1/S phase arrest

在线全文

学校读者我要写书评

暂无评论

Genes & Diseases 2024年第2期11卷 579-581页

作者： Houxiang Jiang Ying Liu Huibin Song jinquan Xia Ying Tian Luolin Wang Mingwei Li Zhenyu xu Zhenglei xu Chang Zou Department of Gastrointestinal Surgery The First Affiliated Hospital of Wannan Medical College (Yijishan Hospital of Wannan Medical College)WuhuAnhui 241001China Anhui Province Clinical Research Center for Critical Respiratory Medicine WuhuAnhui 241001China Department of Clinical Medical Research Center The Second Clinical Medical College (Shenzhen People's Hospital) of Jinan UniversityThe First Affiliated Hospital of Southern University of Science and TechnologyShenzhenGuangdong 518020China Integrated Chinese and Western Medicine Postdoctoral Research Station Jinan UniversityGuangzhouGuangdong 510632China School of Pharmacy Southwest Medical UniversityLuzhouSichuan 646000China Department of Gastroenterology Shenzhen People's Hospital(The Second Clinical Medical CollegeJinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)ShenzhenGuangdong 518020China Precision Medicine Center The First Affiliated Hospital of Wannan Medical College(Yijishan Hospital of Wannan Medical College)WuhuAnhui 241001China School of Medicine Life and Health SciencesThe Chinese University of Hong KongShenzhenGuangdong 518172China

Colorectal carcinoma(CRC),the third most commonly diagnosed cancer,accounts for 9.7%of all newly diagnosed cancer cases and 9.4%of cancer-related deaths globally.1 Recent studies have demonstrated that post-transcriptional RNA modifications,such as N^(6)-methyladenosine,N^(5)-methylcytosine,and N^(7)-methylguanosine,play critical roles in the regulation of mRNA stability and translation,primary microRNA processing,and lncRNA-protein complex that contributes to the progression of human cancer.

关键词： cancer colorectal globally