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On China's High-Speed Railway Technology

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第12期12卷 883-884页

作者： you-tong fang College of Electrical Engineering Zhejiang University Hangzhou 310027 China

Energy and environmental issues have become increasingly prominent in matters of transportation.Compared with road,air,and sea transportation,railway transportation has the advantages of a large transmission capacity,with rapid,safe,and on-time travel,requiring less land resources,with lower energy consumption,less environmental pollution,and the capacity to operate under most weather conditions.In particular,high-speed railway technology has been growing rapidly.Since the world's first high-speed railway was built in Japan in 1964,more than ten countries and regions have developed high-speed railways,operating over a total of more than 10000 km.High-speed railways not only provide the public with a new type of rapid,convenient,safe,and comfortable travel,but also greatly boost the socio-economic development of the country.

关键词：铁路技术中国铁路运输能源消耗环境问题海上运输传输容量环境污染

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 improved.Particular 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 flow.Some important parameters,such as the discharge area,discharge coefficient,fluid bulk modulus,were especially analyzed using numerical methods or by experiment-based estimation.Consequently,the mathematical results of pressure pulsation and flow ripple agree well with experimental results from the test-rig of the flow ripple.Therefore,the cross angle and the pre-compression angle of the valve plate was optimized,based on the pumping dynamics model.Considering 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：水动力学模型交叉角基础优化数值分析方法水动力学特征活塞泵预压缩

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 models.Considering 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 reliability.Then the working processes of the mechanical lifting system and electromagnetic system are demonstrated.With 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 force.At last,the structure optimization of the brake system is discussed.

关键词：高速度的火车混合刺激埃迪刹车有限元素方法

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 lines.Evaluation of magnetic field using analytical technique based on contour integral is presented,in order to assess the electromagnetic environment around a high-speed railway.Actual railway multiconductor finitely long overhead lines are represented by an infinitely long single line above two-layered earth,whose characteristic is different from homogeneous earth.Owing to the constraint of the GB/T 24338-2009 and the high frequency investigated (a few MHz),only the magnetic fields are examined.The magnetic fields consist of four components:the direct wave,the ideal reflected wave or image wave,the trapped surface wave,and the lateral wave.The 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：开销排队二分层的土套住的表面波浪

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) trains.In 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) methods.After 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 systems.On this basis,the operational performance of a traction converter was simulated and analyzed at different train speeds and in different conditions.The simulation results can provide a reference for the actual design and production of a traction converter.

关键词：高速度的火车拖拉司机系统 VC 中国铁路高速度(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 obscurity.It is found that the rail should withstand huge mechanical and thermal shocks during the launching operation.The forms of rail failure are accompanied by gouge,grooving,transition,and arc ablation,etc.The 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 materials.This paper provides a comprehensive review of rail materials,including material composition,preparation,microstructure,and properties.We begin from a short background of the requirement of the rail material.Then a detailed investigation of rail materials is described,and the performances of those materials are introduced.Finally,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