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311.
蒋时军 《变流技术与电力牵引》2011,(3)
介绍了双源式无轨电车的储能系统的基本原理与相关设计要点,特别是根据一种无轨电车运营模式对储能系统容量、储能形式以及能量分配进行了研究,同时在电池箱散热设计中采用了有限元的分析方法,最后通过无轨电车实际运营考核验证了该方法的有效性。 相似文献
312.
中低速磁浮列车技术研究进展 总被引:1,自引:0,他引:1
文章介绍了中低速磁浮列车的技术特点,并从悬浮、直线电机牵引、走行机构三个方面讲述了中低速磁浮列车技术的现状. 相似文献
313.
总结广州在市域快线规划设计方面的经验,基于时空目标的功能定位,提出对线路规划设计的要求。分析国内外大站快线、快慢线组合以及复线等三大快线建设模式的功能差异及优缺点。以广州地铁21号线快慢线规划设计为例,提出规划设计阶段应以如何落实市域快线与线网衔接点、站点布置规划、最高运行速度及运营模式、快线停靠站点选择、投资控制等5个维度为重点研究内容,并逐一进行详细论述和数据比较分析,为新建市域快线的决策、规划设计提供参考。 相似文献
314.
高速铁路列车运行噪声特性研究 总被引:3,自引:0,他引:3
在对我国高速铁路噪声实测的基础上,分析了我国高速铁路噪声的特性。动车组高速运行时,在桥梁区段峰值均出现在低频段(f=31.5~63Hz);路基区段的噪声频谱呈宽频特性,在低频段(f=31.5—63Hz)和中高频段(f=500—8000Hz)声能量均较为集中。高速铁路列车辐射噪声随速度的关系式与国外辐射噪声随速度的关系基本一致,当高速动车组运行速度大于300km/h后,轮轨噪声、空气动力噪声和集电系统噪声成为主要声源。高速列车辐射噪声几何衰减基本遵守距离加倍,声级衰减3—4dB(A)的规律。 相似文献
315.
土压平衡盾构在富水地层掘进中常会发生喷涌问题并产生不良后果,以广州地铁6号线的区间隧道工程为实例进行论证.在盾构机配置双螺旋输送器后,除了具有平衡土压的优良性能外,有效的渣土改良措施是防止喷涌发生的重要因素,加强同步注浆管理、阻断盾尾到达土仓的水力联系通道也至关重要,并提出配置双螺旋输送系统后存在的缺点及需要改进之处. 相似文献
316.
基于单调速器法的并车控制器模型与并车推进装置特性分析 总被引:1,自引:0,他引:1
针对船舶并车推进装置的并车控制问题,介绍了单调速器法的控制原理,建立了基于单调速器法的并车控制器模型,并在动力装置性能仿真模型库的基础上,构建了CODAD并车推进装置的模块化实时仿真模型.分析了在单调速器控制方法下并车推进装置的稳态特性,并车过程和加速过程的动态特性.讨论了控制算法的优化,为控制策略的合理制定提供了理论基础. 相似文献
317.
Liang Ling Qing Zhang Xinbiao Xiao Zefeng Wen Xuesong Jin 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(4):485-505
The resonance vibration of flexible car-bodies greatly affects the dynamics performances of high-speed trains. In this paper, we report a three-dimensional train–track model to capture the flexible vibration features of high-speed train carriages based on the flexible multi-body dynamics approach. The flexible car-body is modelled using both the finite element method (FEM) and the multi-body dynamics (MBD) approach, in which the rigid motions are obtained by using the MBD theory and the structure deformation is calculated by the FEM and the modal superposition method. The proposed model is applied to investigate the influence of the flexible vibration of car-bodies on the dynamics performances of train–track systems. The dynamics performances of a high-speed train running on a slab track, including the car-body vibration behaviour, the ride comfort, and the running safety, calculated by the numerical models with rigid and flexible car-bodies are compared in detail. The results show that the car-body flexibility not only significantly affects the vibration behaviour and ride comfort of rail carriages, but also can has an important influence on the running safety of trains. The rigid car-body model underestimates the vibration level and ride comfort of rail vehicles, and ignoring carriage torsional flexibility in the curving safety evaluation of trains is conservative. 相似文献
318.
Lirong Guo Zaigang Chen Zhiyong Shi Kaikai Lv Tiancheng Ji 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(6):900-922
This paper aims to improve car body stability performance by optimising locomotive parameters when coupler jack-knifing occurs during braking. In order to prevent car body instability behaviour caused by coupler jack-knifing, a multi-locomotive simulation model and a series of field braking tests are developed to analyse the influence of the secondary suspension and the secondary lateral stopper on the car body stability performance during braking. According to simulation and test results, increasing secondary lateral stiffness contributes to limit car body yaw angle during braking. However, it seriously affects the dynamic performance of the locomotive. For the secondary lateral stopper, its lateral stiffness and free clearance have a significant influence on improving the car body stability capacity, and have less effect on the dynamic performance of the locomotive. An optimised measure was proposed and adopted on the test locomotive. For the optimised locomotive, the lateral stiffness of secondary lateral stopper is increased to 7875?kN/m, while its free clearance is decreased to 10?mm. The optimised locomotive has excellent dynamic and safety performance. Comparing with the original locomotive, the maximum car body yaw angle and coupler rotation angle of the optimised locomotive were reduced by 59.25% and 53.19%, respectively, according to the practical application. The maximum derailment coefficient was 0.32, and the maximum wheelset lateral force was 39.5?kN. Hence, reasonable parameters of secondary lateral stopper can improve the car body stability capacity and the running safety of the heavy haul locomotive. 相似文献
319.
Decang Li Jianjun Meng Huan Bai Ruxun Xu 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(7):1028-1050
This paper focuses on the safety of high-speed trains under strong crosswind conditions. A new active control strategy is proposed based on the adaptive predictive control theory. The new control strategy aims at adjusting the attitudes of a train by controlling the new-type intelligent giant magnetostrictive actuator (GMA). It combined adaptive control with dynamic matrix control; parameters of predictive controller was real-time adjusted by online distinguishing to enhance the robustness of the control algorithm. On this basis, a correction control algorithm is also designed to regulate the parameters of predictive controller based on the step response of a controlled objective. Finally, the simulation results show that the proposed control strategy can adjust the running attitudes of high-speed trains under strong crosswind conditions; they also indicate that the new active control strategy is effective and applicable in improving the safety performance of a train based on a host–target computer technology provided by Matlab/Simulink. 相似文献
320.
李之建 《武汉船舶职业技术学院学报》2012,11(3):87-88,101
通过对三相四线系统零线运行故障的分析,发现三相四线中的零线因故断路后,在三相负载不对称时,则会产生变压器中性点位移,致使三相电压不平衡,即有的相电压过高,可能烧毁电器设备,有的相电压过低,使电器设备无法正常使用。为了防止此类故障的发生,通过试实验研究,提出了具体可行的预防措施,以供实际工作中参考. 相似文献