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981.
J. Hur 《International Journal of Automotive Technology》2010,11(4):593-600
Motorization in vehicles is expanding rapidly for fuel efficiency, customer comfort, convenience, and safety features. These
new electric loads represent an increase in the required electric power. This has generated interest in new, higher power
systems such as the 42V Power Net. The electro-hydraulic power steering (EHPS) system is one of these systems. This paper
presents the development of the electric motor-driven pump unit for the EHPS system using a 42V power-Net. The interior type
permanent magnet synchronous motor (IPMSM) can be applied to this system with more power density per volume for compactness
of the EHPS. In order to improve the system, the IPMSM and its control method was optimized for improved torque characteristics
and electric power consumption. The performances of both the pump unit and the IPMSM have been verified by experimental results.
Finally, all in one type the electric motor-driven pump unit are developed from the experiment verification. 相似文献
982.
In this paper, a new non-linear tracking controller for vehicle active suspension systems is analytically designed using an
optimization process. The proposed scheme employs a realistic non-linear quarter-car model, which is composed of a hardening
spring and a quadratic damping force. The control input is the external active suspension force and is determined by minimizing
a performance index defined as a weighted combination of conflicting objectives, namely ride quality, handling performance
and control energy. A linear skyhook model with standard parameters is used as the reference model to be tracked by the controller.
The robustness of the proposed controller in the presence of modeling uncertainties is investigated. The performed analysis
and the simulation results indicate that both vehicle ride comfort and handling performance can be improved using the minimum
external force when the proposed non-linear controller is engaged with the model. Meanwhile, a compromise between different
objectives and control energy can easily be made by regulating their respective weighting factors, which are the free parameters
of the control law. 相似文献
983.
984.
运用无线收发模块和调制解调器组成的计算机通讯网,采用MODBUS通讯协议,实现对采油厂的计量间、中转站、联合站的恒电位仪进行监控和管理。 相似文献
985.
叶轮径向间隙对喷水推进轴流泵性能的影响 总被引:1,自引:0,他引:1
轴流泵作为喷水推进器的核心部件具有推进效率高、抗空化(气蚀)能力强、噪声低等优点。运用计算流体动力学CFD软件-FLUENT,基于标准k-ε紊流模型及SIMPLE算法,对020Q84喷水推进轴流泵内部(及端壁间隙)流场及其运行特性进行了三维数值模拟。研究和分析了三种叶轮径向间隙对轴流泵性能的影响,并进行了性能预估。研究结果为CFD技术在喷水推进轴流泵设计及性能改进中的应用提供了参考。 相似文献
986.
铁路喷漆作业混苯治理措施的研究 总被引:1,自引:0,他引:1
铁路喷漆作业现场及喷漆作业过程中散发在空气中的有机废气[挥发的溶剂(酯、酮、醇类)及稀释剂(煤焦油类、苯、甲苯、二甲苯)]及固体漆雾粒子(树脂、颜染料)。依据国内外各行业喷漆技术发展的动向,找到了解决铁路机务段、车辆段及铁路工厂喷漆作业混苯物污染的控制手段。即:改革工艺采用新技术和新材料,实施上送风下排风空气幕及实施净化措施和加强个体防护的综合治理措施。 相似文献
987.
以京广线孟庙至长台关段为例,介绍在保持既有线正常运营的前提下,采用纵断面调整、路基换填、水泥土挤密桩等工程措施对既有路基进行加固,使其满足200km/h的提速要求。 相似文献
988.
J. Venkatesan G. Nagarajan R. V. Seeniraj R. Murugan 《International Journal of Automotive Technology》2010,11(3):317-322
Mathematical simulation is the process of designing a model of a real system and then conducting experiments with the simulation
to understand the system’s behavior. Mathematical simulation is widely used for investigating and designing compressors, and
with a minimal number of simplifying assumptions, mathematical models can be used in conjunction with modern computing tools
to solve complicated problems. A considerable amount of previous research has focused on the mathematical modeling of reciprocating
air compressors used in automotive braking. The aim of the present work was to experimentally validate the mathematical model
for such compressors. We present a simplified and effective mathematical model for estimating compressor performance, and
this model can easily be executed using personal computers. Parameters such as compressor speed, discharge pressure and clearance
volume were evaluated in terms of their effect on the thermodynamic behavior of compressors. The model can predict cylinder
pressure, cylinder volume, cylinder temperature, valve lift and resultant torque at different crank angles; it can also predict
the free air delivered and the indicated power of the compressor. Therefore, the model has been validated using experimental
results. 相似文献
989.
T. Ciobotaru D. Frunzeti L. Jäntschi 《International Journal of Automotive Technology》2010,11(2):167-172
This paper presents a method for analyzing epicyclic gearboxes by evaluating the speeds, torques and power of the external
elements in epicyclic gear mechanisms, as well as the total ratios of the gear box. The method is based on the equations that
describe each epicyclic gear mechanism and rules that assign appropriate codes to the external elements. The method emphasizes
how power flows are transmitted through the epicyclic gears, as well as power losses. Analysis of an epicyclic gear box is
performed to illustrate the proposed method. 相似文献
990.