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991.
西班牙国家铁路AVE S 103新型高速动车组 总被引:1,自引:0,他引:1
H.Rieger 《变流技术与电力牵引》2003,(2):37-40
西班牙国家铁路(RENFE)于2001年7月向德国Siemens公司订购了16列8节车编组的最高速度为350 km/h的AVE S 103新型电动车组.文章概要介绍了该电动车组的主要特点. 相似文献
992.
Gaspar L. Gil Gómez Alexander Lönnergård Mohit H. Asher Mikael Nybacka Egbert Bakker Lars Drugge 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(7):945-969
Objective testing of vehicle handling in winter conditions has not been implemented yet because of its low repeatability and its low signal-to-noise ratio. Enabling this testing, by identifying robust manoeuvres and metrics, was the aim of this study. This has been achieved by using both experimental data, gathered with steering-robot tests on ice, and simulation models of different complexities. Simple bicycle models with brush and MF-tyre models were built, both optimally parameterised against the experimental data. The brush model presented a better balance in complexity performance. This model was also implemented in a Kalman filter to reduce measurement noise; however, a simpler low-pass filter showed almost similar results at lower cost. A more advanced full vehicle model was built in VI-CarRealTime, based on kinematics and compliance data, damper measurements, and real tyre measurements in winter conditions. This model offered better results and was therefore chosen to optimise the initial manoeuvres through test design and simulations. A sensitivity analysis (ANOVA) of the experimental data allowed one to classify the robustness of the metrics. Finally, to validate the results, the proposed and the initial manoeuvres were tested back to back in a new winter campaign. 相似文献
993.
Heeyun Lee Juyean Sung Hyeokjun Lee Chunhua Zheng Wonsik Lim Suk Won Cha 《International Journal of Automotive Technology》2018,19(4):687-694
In this study, a model-based integrated control method for engines and continuous variable transmissions (CVTs) is developed. CVT refers to a type of transmission which allows an engine to be operated independently with respect to the vehicle speed, with the engine torque and CVT gear ratio controlled in an integrated manner. In the proposed integrated control scheme, engine operating points which minimize the rate of instantaneous fuel consumption are calculated, and the engine target torque and target gear ratio are determined in an integrated manner based on the results of the calculations. Unlike the previous map-based control method, the method introduced in this study does not require an engine torque map or a CVT ratio map for tuning, and the engine torque and CVT ratio are controlled to minimize the amount of fuel used while satisfying the level of acceleration demand from the driver. The control scheme is based on the powertrain model, and the CVT response lag and transmission loss are also considered in the integrated control processes. The algorithm is simulated with various driving cycles, with the simulation results showing that the fuel economy performance of the vehicle system is improved with the newly suggested engine-CVT integrated control algorithm. 相似文献
994.
995.
Mirko Čorić Joško Deur Li Xu H. Eric Tseng Davor Hrovat 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(1):1-26
A collocation-type control variable optimisation method is used to investigate the extent to which the fully active suspension (FAS) can be applied to improve the vehicle electronic stability control (ESC) performance and reduce the braking distance. First, the optimisation approach is applied to the scenario of vehicle stabilisation during the sine-with-dwell manoeuvre. The results are used to provide insights into different FAS control mechanisms for vehicle performance improvements related to responsiveness and yaw rate error reduction indices. The FAS control performance is compared to performances of the standard ESC system, optimal active brake system and combined FAS and ESC configuration. Second, the optimisation approach is employed to the task of FAS-based braking distance reduction for straight-line vehicle motion. Here, the scenarios of uniform and longitudinally or laterally non-uniform tyre–road friction coefficient are considered. The influences of limited anti-lock braking system (ABS) actuator bandwidth and limit-cycle ABS behaviour are also analysed. The optimisation results indicate that the FAS can provide competitive stabilisation performance and improved agility when compared to the ESC system, and that it can reduce the braking distance by up to 5% for distinctively non-uniform friction conditions. 相似文献
996.
The relationship between voltage and current inside a battery, or the impedance, plays an important role in the simulation
and design of hybrid electric vehicle (HEV) power systems. This paper proposes a new approach employing the Bode plot for
evaluation of equivalent circuit parameters for a lithium polymer battery (LiPB) for HEV application. The main concept of
the proposed circuit-parameter-based model approach is the application of a transfer function used to process the frequency
response of the battery for calculation of accurate circuit parameters. Additionally, the Bode plot is also applied to derive
the impedance-based model directly from frequency response measurements for short time simulations and practical use in the
HEV. Two methods for battery modeling are proposed and verified experimentally with the voltage-current profile of a conventional
HEV using the battery measured in this paper. The results show that the proposed circuit-parameter-based technique provides
a satisfactory battery equivalent circuit model. 相似文献
997.
J. -M. Koo C. H. Choi Y. Huh C. -S. Seok 《International Journal of Automotive Technology》2008,9(3):323-327
The limited slip differential (LSD) is a device that enables the driving force to be transmitted from one slipping wheel to
the other by temporarily restraining the differential function when unwanted slipping occurs on muddy or icy roads. Many types
of LSD have been developed, such as mechanical lock, disk clutch, viscous coupling, torsen and multiple clutch. This study
designed a new type of hydraulic LSD using a pressure generator base on a trochoid gear pump and evaluated the performance
of the new design. 相似文献
998.
Fully coupled simulations of two-phase transport in Polymer Electrolyte Fuel Cells (PEFCs) and heat transfer in coolant channels
are performed in order to investigate the effects of cooling channel configuration on the distributions of temperature and
water within PEFCs. When a practical coolant flow rate is applied to large-scale cells for automotive applications, a significant
coolant temperature rise is expected from the coolant inlet to the outlet, particularly under high current density operations,
creating a significant cell temperature gradient along the flow direction as well. Consequently, a two-phase water profile
resulting from evaporation-condensation processes inside PEFCs is also strongly influenced by the cell temperature gradient
from the hot coolant inlet toward the cold coolant outlet regions, demonstrating that both temperature and liquid saturation
strongly depend on the thermal gradient along the coolant flow path. 相似文献
999.
C. Hein S. Hong J. Suh H. Hoffmann N. Kim 《International Journal of Automotive Technology》2008,9(2):211-216
It is essential to develop efficient and cost-effective production methods to achieve or maintain international competitiveness.
An innovative production method, such as rotary blanking, enables manufacturers to both reduce expenses and economize production
time. However, there are not enough numerical analyses for this process. In this paper, numerical simulations of rotary blanking
were performed. After comparing the cutting planes generated by conventional and rotary blanking experimental tests, the cutting
areas of two punch geometries were analyzed. The influence of punch geometry on part quality was then investigated through
simulations. The procedure for die stress analysis was established and stress distributions of the worksheet and the tools
were analyzed. 相似文献
1000.
J. Jung J. H. Lee S. Song K. M. Chun 《International Journal of Automotive Technology》2008,9(4):423-428
Understanding the mechanism of carbon oxidation is important for the successful modeling of diesel particulate filter regeneration.
Characteristics of soot oxidation were investigated with carbon black (Printex-U). A flow reactor system that could simulate
the condition of a diesel particulate filter and diesel exhaust gas was designed. Kinetic constants were derived and the reaction
mechanisms were proposed using the experimental results and a simple reaction scheme, which approximated the overall oxidation
process in TPO as well as CTO. From the experiments, the apparent activation energy for carbon oxidation with NO2-O2-H2O was determined to be 40±2 kJ/mol, with the first order of carbon in the range of 10∼90% oxidation and a temperature range
of 250∼500°C. This value was exceedingly lower than the activation energy of NO2-O2 oxidation, which was 60±3 kJ/mol. When NO2 exists with O2 and H2O, the reaction rate increases in proportion to NO2. It increases nonlinearly with O2 or H2O concentration when the other two oxidants are fixed. 相似文献