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在铁路建设事业蒸蒸日上的背景下,电气化牵引供电系统建设已经成为铁路建设的一个重点环节,并且同属四电建设的目标之一.铁路的信号系统属于弱电系统,在电气化牵引供电系统中,容易受到干扰,导致信号设备的运行或是数据输入输出发生异常,从而引发一些不必要的安全事故.本文对电气化牵引供电和铁路信号做了简单介绍,深入分析了信号设备受到电气化牵引供电的影响,提出了一些简单的应对策略. 相似文献
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研究和综述了现有文献关于“磁悬浮列车及其工程技术”方面的论述,其中包括“磁悬浮列车及其铁路工程技术的发展”,“磁悬浮浮列车的悬浮与导向”,“磁悬浮列车的牵引与制动”,“磁悬浮高速铁路的供电方式”,“磁悬浮高速铁路线路及其选线”等。 相似文献
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推导和证明了Haar小波连续小波变换时间和尺度的周期性,指出这种周期性可以提取出信号中的周期成分,并且使谐波和冲击信号在时间-尺度域中有不同的图形特征。因此根据这些特性可以识别齿轮裂纹产生的冲击和刚度变化,仿真和汽车变速器齿轮故障分析验证了Haar小波变换的有效性和实用性。 相似文献
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为研究路基振动压实过程中振动轮动力学响应的产生机理,进而为连续压实监测技术中的谐波比类指标提供理论支撑,基于有限元方法,分别考虑了纯弹性和弹塑性2种土体本构模型,针对振动压实过程中的加速度信号进行了仿真分析,分别研究了几何非线性、接触非线性以及材料非线性对加速度信号畸变的影响,探讨了加速度信号频谱中谐波分量和次谐波分量的产生机理,并对其随弹性模量、黏聚力等土体参数的变化规律进行了分析。其中,弹性模型在发生跳振之前,可以分析几何非线性和由于接触面积变化引起的接触非线性的影响,在发生跳振之后,可以用来考虑由于脱空引起的接触非线性的影响,弹塑性模型可以反映材料非线性的影响。研究结果表明:几何非线性对加速度信号畸变的影响不大,材料非线性和接触面积变化引起的接触非线性是加速度信号谐波分量的产生原因,而跳振引起的接触非线性是次谐波分量的产生原因。此外,随着压实过程的进行,土体模量和屈服极限同时提高,接触面积变化引起的接触非线性增强,但材料非线性的影响减弱,由于压实的中后期土体弹性因素占据了主导地位,塑性变形量很小,同时由于局部脱空的影响,导致实际工程中,随着压实过程的进行,二次谐波分量呈增大趋势。最后,跳振不仅会引起次谐波分量,还会导致谐波分量量值的减小,同时跳振发生前后加速度波形并不是连续变化,而是发生了突变。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(3):185-210
Summary The research and development (R & D) of maglev technology had made a great progress in China since the early 1980s. Especially, a 35 km-long Shanghai high-speed maglev railway employing the German Transrapid system began to be constructed on March 1, 2001. Based on the Transrapid system, the paper develops a 10-degree-of-freedom model of maglev vehicle running over three types of guideways with constant speed. Random guideway irregularities are discussed and taken into account for simulation of the vehicle response and for evaluation of the ride comfort. Using the direct time integration method and the discrete fast Fourier transform (DFFT), random responses of the maglev vehicle-guideway systems are obtained and analyzed. Numerical results show that the resonant frequency of car body acceleration response is 0.5–1 Hz, and there is a 2.2 Hz periodic vibration due to the periodic configuration of rigid piers when the maglev vehicle travels over the elevated-beam guideway. The car body acceleration power spectral density (PSD) curves meet well the ride quality criterion of the urban tracked aircushion vehicle (UTACV) and the maximum acceleration of car body is less than 0.05 g. Moreover, the Sperling ride index values are less than 2.5 as long as the operational speed is less than 450 km/h. It is concluded that the maglev vehicle ride quality is quite well. 相似文献
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C. F. Zhao W. M. Zhai 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2002,38(3):185-210
Summary The research and development (R & D) of maglev technology had made a great progress in China since the early 1980s. Especially, a 35 km-long Shanghai high-speed maglev railway employing the German Transrapid system began to be constructed on March 1, 2001. Based on the Transrapid system, the paper develops a 10-degree-of-freedom model of maglev vehicle running over three types of guideways with constant speed. Random guideway irregularities are discussed and taken into account for simulation of the vehicle response and for evaluation of the ride comfort. Using the direct time integration method and the discrete fast Fourier transform (DFFT), random responses of the maglev vehicle-guideway systems are obtained and analyzed. Numerical results show that the resonant frequency of car body acceleration response is 0.5-1 Hz, and there is a 2.2 Hz periodic vibration due to the periodic configuration of rigid piers when the maglev vehicle travels over the elevated-beam guideway. The car body acceleration power spectral density (PSD) curves meet well the ride quality criterion of the urban tracked aircushion vehicle (UTACV) and the maximum acceleration of car body is less than 0.05 g. Moreover, the Sperling ride index values are less than 2.5 as long as the operational speed is less than 450 km/h. It is concluded that the maglev vehicle ride quality is quite well. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(12):1077-1095
A new dynamic model of a high-speed EMS maglev vehicle/guideway interaction is presented. The model considers the vehicle and the guideway as an integral system and couples vertical interaction with lateral interaction. The vehicle subsystem is modeled as a multi-body system, which runs on the guideway with a constant velocity. The guideway substructure is modeled as an elastic beam. The attractive magnetic forces between vehicle and guideway are decided by controller, observer, and filter. A special simulation program is developed. Numerical results of the program are compared with test results. The results show that the coupling model is appropriate and the simulation program is credible primarily. Applications of coupling model to the investigation of the effect of irregularities on maglev system are reported at the end of the paper. The studies in this paper can be used to evaluate and optimize dynamic performances of the high-speed EMS maglev system. 相似文献
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Jin Shi Qingchao Wei Yang Zhao 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(12):1077-1095
A new dynamic model of a high-speed EMS maglev vehicle/guideway interaction is presented. The model considers the vehicle and the guideway as an integral system and couples vertical interaction with lateral interaction. The vehicle subsystem is modeled as a multi-body system, which runs on the guideway with a constant velocity. The guideway substructure is modeled as an elastic beam. The attractive magnetic forces between vehicle and guideway are decided by controller, observer, and filter. A special simulation program is developed. Numerical results of the program are compared with test results. The results show that the coupling model is appropriate and the simulation program is credible primarily. Applications of coupling model to the investigation of the effect of irregularities on maglev system are reported at the end of the paper. The studies in this paper can be used to evaluate and optimize dynamic performances of the high-speed EMS maglev system. 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(2):145-156
Fully enclosed motorcycles could form the basis for extremely fuel and space efficient vehicles, but their inherent instability upon encountering even a momentary loss of traction renders them unsuitable for general use. It will be shown that a relatively simple tilt control system using a gyroscope to provide a tilt control moment is capable of stabilizing the vehicle at still stand or at speed on a very low traction surface. Furthermore, the system can achieve a coordinated turn on high traction surfaces. Since the gyro is an energy storage device, it can be used also in a hybrid system to provide extra power for acceleration and to recover some energy during braking. This relatively old idea should be reconsidered in light of the improved electromechanical devices, which have been developed recently for hybrid electric vehicles. 相似文献
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Z. L. Wang G. Q. Li Y. B. Yang S. W. Chen X. L. Zhang 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2019,57(2):161-191
This study presents a more realistic modelling of the maglev-based high-speed railway line in Shanghai, China. Focus is placed on an accurate simulation of the two subsystems: the train subsystem including the magnets and the viaduct subsystem including the modular function units of the rails. The electromagnet force–air gap model with a proportional-derivative (PD) controller is adopted to simulate the interaction between the maglev train via its electromagnets and the viaduct via its modular function units. The flexibilities of the rails, girders, piers and associated elastic bearings are all considered in the modelling of the viaduct subsystem to investigate their effects on an interaction between the two subsystems. By applying the proposed model to the Shanghai maglev line, the essential characteristics of the coupled system can be duly captured. The accuracy and effectiveness of the proposed approach are then validated by comparing the computed dynamic responses and frequencies with the measurement results. It is confirmed that the proposed modelling with a detailed simulation of the magnets and modular function units can duly account for the dynamic interaction between the train and viaduct systems. Moreover, the effects of the inclusion of the flexibilities of the rails, girders and elastic supports to the response of the coupled system are respectively investigated, the results of which prove that their involvements are essential to the accurate prediction of the response of the coupled maglev train–viaduct system. 相似文献
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Dean Karnopp 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2002,37(2):145-156
Fully enclosed motorcycles could form the basis for extremely fuel and space efficient vehicles, but their inherent instability upon encountering even a momentary loss of traction renders them unsuitable for general use. It will be shown that a relatively simple tilt control system using a gyroscope to provide a tilt control moment is capable of stabilizing the vehicle at still stand or at speed on a very low traction surface. Furthermore, the system can achieve a coordinated turn on high traction surfaces. Since the gyro is an energy storage device, it can be used also in a hybrid system to provide extra power for acceleration and to recover some energy during braking. This relatively old idea should be reconsidered in light of the improved electromechanical devices, which have been developed recently for hybrid electric vehicles. 相似文献
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为了降低高速列车从始发站至终到站运行的牵引能耗, 研究了针对多列车区间运行时分同步分配的列车运行图节能优化方法。基于高速列车在站间采用的“四阶段”操纵策略构建最优驾驶策略集, 以牵引距离和巡航距离为变化因子, 以牵引能耗和区间运行时分为计算目标, 求解出最优驾驶策略集里牵引能耗与区间运行时分的线性关系。在此基础上构建多列车区间运行时分最优分配的节能运行图模型。模型以牵引能耗最低为目标, 考虑了列车总运行时间约束、变量取值范围约束以及安全间隔时分约束。在模型求解方面, 选取拉格朗日松弛算法, 将复杂约束松弛至目标函数当中, 从而把原问题分解为各区间可独立求解的子问题, 利用次梯度优化的方法得出精确解, 实现了多列车区间运行时分同步分配的目标。以宝兰高速铁路为背景进行算例验证, 结果表明: 通过重新分配区间运行时分, 10列车总共节约了595.958 kW·h牵引能耗, 平均节能率达到了1.2%;从运行图的层面分析, 该算例下通过调整区间运行时分的节能方法对其影响幅度较小, 具有较强的现实意义; 所提出的模型及算法的计算时间为10 s, 针对列车开行对数较多的高速铁路, 可有效提高求解效率。 相似文献
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介绍了高速开关阀的特点及在沥青混凝土摊铺机自动找平控制系统中的应用,设计了一套高速开关阀控制方案,并在实验室建立了实验台,通过实验对传统普通电磁阀控制方案和高速开关阀控制方案进行了比较,得到了比较详细的实验数据。实验结果表明,高速开关阀可以较好地应用到自动找平控制系统中,对提高系统响应时间、减小开关控制死区的影响有较好的作用,但过高的调制频率对系统的影响并没有太大好处。 相似文献
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Xiukun Wei Ming Zhu Limin Jia 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(7):982-1003
The high-speed train has achieved great progress in the last decades. It is one of the most important modes of transportation between cities. With the rapid development of the high-speed train, its safety issue is paid much more attention than ever before. To improve the stability of the vehicle with high speed, extra dampers (i.e. anti-hunting damper) are used in the traditional bogies with passive suspension system. However, the curving performance of the vehicle is undermined due to the extra lateral force generated by the dampers. The active suspension systems proposed in the last decades attempt to solve the vehicle steering issue. However, the active suspension systems need extra actuators driven by electrical power or hydraulic power. There are some implementation and even safety issues which are not easy to be overcome. In this paper, an innovative semi-active controlled lateral suspension system for railway vehicles is proposed. Four magnetorheological fluid dampers are fixed to the primary suspension system of each bogie. They are controlled by online controllers for enhancing the running stability on the straight track line on the one hand and further improving the curving performance by controlling the damper force on the other hand. Two control strategies are proposed in the light of the pure rolling concept. The effectiveness of the proposed strategies is demonstrated by SIMPACK and Matlab co-simulation for a full railway vehicle with two conventional bogies. 相似文献