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Optimization of cross angle based on the pumping dynamics model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第3期11卷 181-190页

作者： Ji-en MA you-tong fang Bing XU Hua-yong YANG School of Electrical Engineering Zhejiang UniversityHangzhou 310027China State Key Lab of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China

The single cylinder and multi-cylinder pumping dynamics model of a swash plate piston pump were *** attention has been paid to the design influences of key parts of the valve plate such as relief groove,pre-compression/ expansion and fluid inertia effect of the unsteady *** important parameters,such as the discharge area,discharge coefficient,fluid bulk modulus,were especially analyzed using numerical methods or by experiment-based ***,the mathematical results of pressure pulsation and flow ripple agree well with experimental results from the test-rig of the flow ***,the cross angle and the pre-compression angle of the valve plate was optimized,based on the pumping dynamics *** both the flow ripple and the cylinder pressure of the pump,the cross angle is set to be 2.2° to 2.7° with a pre-compression angle of 1.7° to 2.2°,so the pumping dynamics character can obtain the best result.

关键词： Flow ripple Pressure pulsation Piston pump Noise

Design and analysis of the hybrid excitation rail eddy brake system of high-speed trains

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 936-944页

作者： Ji-en MA Bin ZHANG Xiao-yan HUANG you-tong fang Wen-ping CAO College of Electrical Engineering Zhejiang University Hangzhou 310027 China The Key State Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Newcastle University Newcastle upon Type NE1 7RU UK

Compared to the current eddy braking patterns using a single magnetic source,hybrid excitation rail eddy brakes have many advantages,such as controllability,energy saving,and various operating *** the large braking power consumption of the high-speed train,a hybrid excitation rail eddy brake system,which is based on the principle of electromagnetic field,is proposed to fulfill the needs of safety and *** the working processes of the mechanical lifting system and electromagnetic system are *** the electromagnetic system analyzed using the finite element method,the factors such as speed,air gap,and exciting current have influences on the braking force and attractive *** last,the structure optimization of the brake system is discussed.

关键词： High-speed train Hybrid excitation Eddy brake Finite element method

Electromagnetic environment around a high-speed railway using analytical technique

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 950-956页

作者： Yong-jian ZHI Bin ZHANG Kai LI Xiao-yan HUANG you-tong fang Wen-ping CAO College of Electrical Engineering Zhejiang University Hangzhou 310027 China State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China Newcastle University Newcastle upon Type NE1 7RU UK

A switched-mode unit used in electric locomotive generates a strong high frequency conducted electromagnetic interference (EMI),which radiates electromagnetic energy through railway *** of magnetic field using analytical technique based on contour integral is presented,in order to assess the electromagnetic environment around a high-speed *** railway multiconductor finitely long overhead lines are represented by an infinitely long single line above two-layered earth,whose characteristic is different from homogeneous *** to the constraint of the GB/T 24338-2009 and the high frequency investigated (a few MHz),only the magnetic fields are *** magnetic fields consist of four components:the direct wave,the ideal reflected wave or image wave,the trapped surface wave,and the lateral *** calculation results proved that due to the presence of the trapped surface wave,the magnetic field of the observer point on the interface is strongly influenced,when the line is on or closed to the interface.

关键词： Overhead lines Two-layered earth Trapped surface wave

Simulation software for CRH2 and CRH3 traction driver systems based on SIMULINK and VC

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 945-949页

作者： Qin-fen LU Bin WANG Xiao-yan HUANG Ji-en MA you-tong fang Jin YU Wen-ping CAO College of Electrical Engineering Zhejiang University Hangzhou 310027 China National Engineering Laboratory for System Integration of High-Speed Train （South） CSR Qingdao Sifang Co. Ltd. Qingdao 266111 China Newcastle University Newcastle Upon Type NE1 7RU UK

Simulation models of traction driver systems were established using SIMULINK,according to the actual structure and parameters of China Railway High-Speed 2 (CRH2) and China Railway High-Speed 3 (CRH3) *** these models,the traction motor adopts transient current control and an indirect rotor magnetic field orientation vector control strategy,and the traction converter uses sinusoidal pulse width modulation (SPWM) and space vector pulse width modulation (SVPWM) *** these models are transformed in VC++ program,and a friendly interface and data processing system are constructed,simulation software is obtained for CRH2 and CRH3 traction driver *** this basis,the operational performance of a traction converter was simulated and analyzed at different train speeds and in different *** simulation results can provide a reference for the actual design and production of a traction converter.

关键词： High-speed train Traction driver system VC China Railway High-Speed (CRH)

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世界三代压水堆主要机型技术分析（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第11期17卷 911-922页

作者： Yong WANG Ji-en MA you-tong fang Shanghai Nuclear Engineering Research and Design Institute Shanghai 200233China College of Electrical Engineering Zhejiang UniversityHangzhou 310027China

本文针对目前主要的第三代压水堆机型EPR、AES2006以及CAP1400,从核电厂设计理念,综合性能、安全性和经济性等方面进行对比分析。在此基础上,结合福岛核事故,探讨中国商用核电未来的技术发展方向。通过对EPR、AES2006以及CAP1400的对比... 详细信息

本文针对目前主要的第三代压水堆机型EPR、AES2006以及CAP1400,从核电厂设计理念,综合性能、安全性和经济性等方面进行对比分析。在此基础上,结合福岛核事故,探讨中国商用核电未来的技术发展方向。通过对EPR、AES2006以及CAP1400的对比分析发现,尽管它们采用了不同的设计理念和技术方式,但作为目前第三代商用压水堆的代表机型,其目标都在于提高核电厂的整体性能、安全性能和经济性,从而在提高安全性的前提下,强化其相比于其他发电方式的竞争力,获得政府、公众和业主的支持。第三代压水堆技术的主要努力方向在于:在安全方面,进一步强化纵深防御体系,将设计加强工况(包括全厂断电、商用飞机撞击和预期未能停堆的瞬态等)纳入设计考虑的范畴;设置预防和缓解严重事故的措施;考虑极端外部事件设防(包括地震和洪水等)。再者,对非能动安全与能动安全两者之间的关系定位、相互衔接进行优化设置,从而更好的保障核安全。此外,严重事故下设备和仪表的可用性成为福岛核事故后需要特别关注的问题。从经济性的角度讲,加强设计简化和标准化,及时将EPR、AES2006以及CAP1400的首台组的建造经验反馈到后续机组,改进可建造性和模块化从而确保经济性和缩短建造周期。从运行的角度讲,考虑国内核电装机容量的增加、较长的设计寿命以及其他可再生能源的并网,核电设计需强化负荷跟踪的能力。长期来看,需要考虑可能的气候变化,从而确保核电站(沿海和内陆)具有较强的应对极端气候以及较高环境温度和冷却水升温的能力。

关键词：第三代压水堆技术性能安全性经济性核电

A fault tolerant single sided matrix converter for flight control actuation systems

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第11期13卷 866-874页

作者： Xiao-yan HUANG Mao-jing JIY Jian-cheng ZHANG Qin-fen LU you-tong fang Andrew GOODMAN Chris GERADA College of Electrical Engineering Zhejiang University Hangzhou 310027 China High Technology Research and Development Center Ministry of Science and Technology Beijing 100044 China University of Nottingham Nottingham NG72RD UK

We describe a single sided matrix converter (SSMC) designed for safety critical applications like flight control actuation systems. Dynamic simulations of multi-phase SSMC using Matlab Simulink are carried out to evaluate the fault tolerance capabilities. Investigation into different numbers of phases and power converter topologies under single phase open circuit, single switch open circuit, and single switch short circuit has been executed. The simulation results confirm 5-phase SSMC design as a compromise between fault tolerance and converter size/volume. A 5-phase SSMC prototype was built. Experimental results verify the effectiveness of our design.

关键词： Single sided matrix converter Fault tolerance Flight control actuation systems

Research progress on advanced rail materials for electromagnetic railgun technology

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Defence Technology（防务技术） 2021年第2期17卷 429-439页

作者： Hong-bin Xie Hui-ya Yang Jian Yu Ming-yu Gao Jian-dong Shou you-tong fang Jia-bin Liu Hong-tao Wang School of Materials Science and Engineering Zhejiang UniversityHangzhou310027China Center for X-mechanics Faculty of EngineeringZhejiang UniversityHangzhou310027China

Electromagnetic railgun attracts more and more attention due to its advantage in speed,cost,and *** is found that the rail should withstand huge mechanical and thermal shocks during the launching *** forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,*** service life of the rail has become a bottleneck restricting the development of electromagnetic railgun technology.A series of researches are carried out to solve rail failure,including analysing the failure mechanism and using various advanced rail *** paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and *** begin from a short background of the requirement of the rail *** a detailed investigation of rail materials is described,and the performances of those materials are ***,further development prospect of rail material is discussed.

关键词： Strength Conductivity Electromagnetic railgun Copper alloys Rai

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中国高速铁路的可持续发展战略（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2016年第12期17卷 923-932页

作者： Ping TAN Ji-en MA Jing ZHOU you-tong fang School of Automation and Electrical Engineering Zhejiang University of Science and Technology China Academy of West Region Development Zhejiang University College of Electrical Engineering Zhejiang University

2008年以来,通过引进和消化国外高速铁路先进技术,联合设计生产和在此基础上的再创新,中国高速铁路技术进入了世界前列,并建成了世界上规模最大,技术水平最高的高速铁路网,大幅改善了中国的交通状况,带动了区域经济和装备制造业的发展... 详细信息

2008年以来,通过引进和消化国外高速铁路先进技术,联合设计生产和在此基础上的再创新,中国高速铁路技术进入了世界前列,并建成了世界上规模最大,技术水平最高的高速铁路网,大幅改善了中国的交通状况,带动了区域经济和装备制造业的发展。新的中长期铁路网规划的发布和"一带一路"及中国铁路"走出去"战略的实施,给高速铁路技术提出了新的要求。未来需要将现代科学的最新进展与高速铁路建设、运营、维护和管理的工程进一步结合,通过创新支撑中国乃至世界高速铁路的可持续发展。

关键词：高速铁路技术创新可持续发展

基于全局热网络和局部流体动力学建模的全封闭永磁牵引电机热性能优化（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第11期19卷 878-888页

作者： Wei CHEN Gui-chu WU you-tong fang Ji-en MA Key Laboratory of Low-Voltage Apparatus Intellectual Technology of Zhejiang Wenzhou University College of Electrical Engineering Zhejiang University

目的:提出一种适用于全封闭冷却结构的电机热性能优化模型,设计一台600 kW的高速列车用永磁牵引电机。创新点:1.通过耦合局部流体动力学模型的方法求解电机复杂冷却风道内的对流传热系数,并在全局热网络模型的框架内得到快速、准确的电... 详细信息

目的:提出一种适用于全封闭冷却结构的电机热性能优化模型,设计一台600 kW的高速列车用永磁牵引电机。创新点:1.通过耦合局部流体动力学模型的方法求解电机复杂冷却风道内的对流传热系数,并在全局热网络模型的框架内得到快速、准确的电机温升结果以用于结构优化;2.在冷却风道中引入栅格结构,采用热性能分析模型优化冷却结构,提升电机热性能;3.通过三维流体动力学模型计算电机局部温升最大值,并提山一种预测特定结构下电机铁损工作阈值的工程方法。方法:1.采用热网络法建立全局热网络模型(图3),并通过耦合局部流体动力学模型计算风道内的热网络参数(图4和6); 2.应用田口设计法对电机风道结构进行优化,并研制样机进行验证(计算与试验结果见表5); 3.假设铁损的谐波附加值与磁密值成正比,通过三维流体动力学模型计算给山端部绕组、永磁体温升值与铁损的预测曲线,并用样机试验进行验证。结论:1.采用全局热网络和局部流体动力学建模的方法可以快速、正确地计算复杂冷却结构下的电机温升分布,且优化后的冷却结构至少可以提升文中电机15%的热性能;2.本文提出的优化模型适用于全封闭风冷或者水冷等冷却结构相对独立且尚无经验公式可参考的电机热性能优化设计;3.铁损工作阈值的预测方法可以为电磁和控制系统设计提供参考。

关键词：热网络模型流体动力学永磁电机全封闭强制风冷