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Yang S.,Southwest Jiaotong University | Wang X.,CSR Qingdao Sifang Locomotive Rolling Stock Co. | Cao B.,Southwest Jiaotong University | Gu Z.,Southwest Jiaotong University | And 4 more authors.
Gaoya Dianqi/High Voltage Apparatus | Year: 2015

This paper reviews the recent progress in researches on arc and arc temperature field between pantograph and catenary with respect to the arc model, arc energy, characteristics of arc radiation, and so on. The current researches on arc model and its characteristics are introduced briefly. The impact of arc energy between pantograph and catenary on the pantograph-catenary system and the arc radiation characteristics are discussed. In addition, it is pointed out that the research on arc temperature field between pantograph and catenary is still facing many problems, such as complex environment of multi-field coupling where arc exists, establishment of new arc model, and difficult calculation of fluid. ©, 2015, Xi'an High Voltage Apparatus Research Institute. All right reserved. Source

Kang Z.,Dalian University of Technology | Wang X.,CSR Qingdao Sifang Locomotive Rolling Stock Co. | Luo Z.,University of Technology, Sydney
Journal of Mechanical Design, Transactions of the ASME | Year: 2012

This paper investigates the simultaneous optimal distribution of structural material and trilevel actuation voltage for static shape control applications. In this optimal design problem, the shape error between the actuated and the desired shapes is chosen as the objective function. The energy and the material volume are taken as constraints in the optimization problem formulation. The discrete-valued optimization problem is relaxed using element-wise continuous design variables representing the relative material density and the actuation voltage level. Artificial interpolation models which relate the mechanical/piezoelectrical properties of the material and the actuation voltage to the design variables are employed. Therein, power-law penalization functions are used to suppress intermediate values of both the material densities and the control voltage. The sensitivity analysis procedure is discussed, and the design variables are optimized by using the method of moving asymptotes (MMA). Finally, numerical examples are presented to demonstrate the applicability and effectiveness of the proposed method. It is shown that the proposed method is able to yield distinct material distribution and to suppress intermediate actuation voltage values as required. © 2012 American Society of Mechanical Engineers. Source

Luo S.,State Grid Corporation of China | Sun J.,China Electric Power Research Institute | Wu G.,Southwest Jiaotong University | Xu Y.,CSR Qingdao Sifang Locomotive Rolling Stock Co. | And 2 more authors.
Gaoya Dianqi/High Voltage Apparatus | Year: 2015

To research impedance properties change in the process of water losing from polluted insulator surface, the pollution near electrified railway is collected and analyzed. The experiment result show that when the contamination moisture content is reduced to certain degree, its impedance angle growing exponentially while amplitude not obviously. In artificial pollution experiment, the pollution impedance and its angle characteristics of difference pollution levels are analyzed in drying process. Results show that when water content is the same, the higher of pollution level, the smaller of the impedance angle, the greater of the impedance amplitude. When proportions of equivalent salt deposit density (ESDD) and non-soluble deposit density (NSDD) are same, the impedance angle variation significantly. The influence of ESDD to pollution impedance is obvious. According to the experimental research, a method of insulator pollution degree monitoring is proposed by taking use of the impedance angle and amplitude changing regulation in the process of water losing from the contamination. This is added up to the traditional leakage current monitoring method. ©, 2015, Xi'an High Voltage Apparatus Research Institute. All right reserved. Source

Ding S.-S.,Beijing Jiaotong University | Ding S.-S.,CSR Qingdao Sifang Locomotive Rolling Stock Co. | Li Q.,Beijing Jiaotong University | Tian A.-Q.,CSR Qingdao Sifang Locomotive Rolling Stock Co. | And 2 more authors.
Acta Mechanica Sinica/Lixue Xuebao | Year: 2016

Compared with the traditional train, the operational speed of the high-speed train has largely improved, and the dynamic environment of the train has changed from one of mechanical domination to one of aerodynamic domination. The aerodynamic problem has become the key technological challenge of high-speed trains and significantly affects the economy, environment, safety, and comfort. In this paper, the relationships among the aerodynamic design principle, aerodynamic performance indexes, and design variables are first studied, and the research methods of train aerodynamics are proposed, including numerical simulation, a reduced-scale test, and a full-scale test. Technological schemes of train aerodynamics involve the optimization design of the streamlined head and the smooth design of the body surface. Optimization design of the streamlined head includes conception design, project design, numerical simulation, and a reduced-scale test. Smooth design of the body surface is mainly used for the key parts, such as electric-current collecting system, wheel truck compartment, and windshield. The aerodynamic design method established in this paper has been successfully applied to various high-speed trains (CRH380A, CRH380AM, CRH6, CRH2G, and the Standard electric multiple unit (EMU)) that have met expected design objectives. The research results can provide an effective guideline for the aerodynamic design of high-speed trains. © 2016 The Chinese Society of Theoretical and Applied Mechanics; Institute of Mechanics, Chinese Academy of Sciences and Springer-Verlag Berlin Heidelberg Source

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