电动汽车的现状和发展趋势

综述了世界范围内电动汽车，混合动力电动汽车和燃料电池电动汽车当前的发展特点和规律。这3种电动汽车目前处在不同的发展阶段，面临不同的问题，并各自具有不同的发展策略。但是，发展电动汽车的工程哲学及一些关键技术，诸如先进电机驱动技术，能源技术，能源控制和管理技术，先进底盘和车体技术等是可共享的。成为现代电动汽车的基础。最后总结了这3种电动汽车的市场前景。     

我国新能源汽车产业发展现状、问题及对策

<正>概念与意义新能源汽车是指采用非常规的车用燃料作为动力来源(或使用常规的车用燃料、采用新型车载动力装置),综合车辆的动力控制和驱动方面的先进技术,形成的技术原理先进,具有新技术、新结构的汽车。新能源汽车包括:混合动力汽车(HEV)、纯电动汽车(BEV)、燃料电池汽车(FCEV)、氢发动机汽车以及燃气汽车、醇醚汽车等。发展现状与问题中国新能源汽车产业始于21世纪初。2001年,我国启动了"863"计划电动汽车重大专项,涉及的电动汽车包括三类:纯     

基于支持向量机的纯电动汽车经济性换挡控制

为了延长纯电动汽车续驶里程,文章应用基于支持向量机的方法对纯电动汽车实现经济性换挡控制,通过试验数据获得电机、逆变器和变速器的效率特性,建立纯电动汽车的能量消耗模型;在城市道路循环工况(UDDS)下应用车速和加速度双参数获得经济性最优挡位信息,形成学习数据库;应用支持向量机分类器和传统换挡规律在欧洲行驶工况(ECE)下进行在线预测和仿真对比。该文对纯电动汽车变速器智能换挡控制的研究,对于提高整车经济性具有一定的理论意义和实用价值。     

电动汽车CAN总线驱动控制系统设计

针对电动汽车电驱动系统中存在的关键技术问题,设计了基于CAN(controller area network)总线的电动汽车电驱动系统。系统由CAN通信模块和电机控制模块组成。CAN通信模块采用新型CAN总线收发器TJA1040和独立CAN控制器,并采用各种抗干扰措施以保证CAN通信的稳定性;控制模块利用模糊矢量控制方案——直接速度控制(direct speed control,DSC)策略,实现电驱动系统高鲁棒性控制。系统兼容性强,可以作为单独模块连接到电动汽车的主干网络上,还可以通过CAN总线对其进行扩展。     

法国大力扶植电动汽车

现在,法国政府对使用电动汽车的用户实行鼓励和奖励政策。发展和普及电动汽车遇到的最大难题是成本问题,无论是制造成本,还是运行成本,电动汽车都比汽油车高10％左右,因此,政府对城镇、乡村的电动汽车用户予以两种补贴:一种是折旧比例高(大致相当于电动汽车高于汽油车的部分)。另一     

XL纯电动轿车获必比登挑战赛5项最优奖

随着石油资源的枯竭、人们环保意识的提高，纯电动汽车及混合动力汽车将成为新世纪前几十年汽车发展的主流。在美国，已有几个州要求制造商开发和销售零排放汽车。各大汽车公司纷纷开发出纯电动汽车，包括通用公司Saturn EV1铅酸电池电动汽车、福特公司的Ranger载货车、克莱斯勒公司的EPIC汽车、丰田公司的RAV4LV汽车、日产公司的ALTRAEV汽车，标致106汽车等。我国政府已经在国家高技术研究发展计划(863计划)中专门有电动汽车重大专项(包括燃料电池整车、混合动力整车和纯电动车)，XL纯电动轿车项目就是其子项目之一。     

分布式驱动电动汽车动力转向系统混杂系统动力学及其切换控制

分布式驱动电动汽车是燃油汽车和电动汽车过渡的一种新型新能源汽车,动力转向系统(ECIPS) 作为电动化底盘集成控制系统(ECIS)的主要组成部分,对电动汽车的设计与装配具有重要的影响. 动力转向系统具有典型的不确定性、未建模动态、测量噪声和干扰等非线性动力学特征,是包含离散事件与连续事件的混杂动力学系统. 分析了分布式驱动电动汽车动力转向系统的控制结构、控制功能及其动力学行为,基于动力转向系统的输入/输出功能、控制状态和控制系统实现流程,建立了反映连续和离散控制行为的混杂控制系统模型. 建立了动力转向系统的混杂控制流程和切换控制结构,进行了25km/h和45km/h下的蛇形实验. 结果表明：在25km/h下,转向系统转矩的峰值和平均值分别降低了41.68%和41.79%, 在45km/h下,转向系统转矩的峰值和平均值分别降低了30.92%和30.67%,转向轻便性得到明显改善.混杂系统动力学模型及其混杂控制结构反映了分布式驱动电动汽车动力转向系统的动力学行为及其控制特征,不仅揭示了动力转向系统的连续系统工作行为,也反映了离散事件特征,对分布式驱动电动汽车控制性能的改善、智能化水平的提高提供了理论研究意义和工程研究价值.     

分布式驱动电动汽车动力转向系统混杂系统动力学及其切换控制（英文）

分布式驱动电动汽车是燃油汽车和电动汽车过渡的一种新型新能源汽车,动力转向系统(ECIPS)作为电动化底盘集成控制系统(ECIS)的主要组成部分,对电动汽车的设计与装配具有重要的影响.动力转向系统具有典型的不确定性、未建模动态、测量噪声和干扰等非线性动力学特征,是包含离散事件与连续事件的混杂动力学系统.分析了分布式驱动电动汽车动力转向系统的控制结构、控制功能及其动力学行为,基于动力转向系统的输入/输出功能、控制状态和控制系统实现流程,建立了反映连续和离散控制行为的混杂控制系统模型.建立了动力转向系统的混杂控制流程和切换控制结构,进行了25km/h和45 km/h下的蛇形实验.结果表明:在25 km/h下,转向系统转矩的峰值和平均值分别降低了41.68%和41.79%,在45 km/h下,转向系统转矩的峰值和平均值分别降低了30.92%和30.67%,转向轻便性得到明显改善.混杂系统动力学模型及其混杂控制结构反映了分布式驱动电动汽车动力转向系统的动力学行为及其控制特征,不仅揭示了动力转向系统的连续系统工作行为,也反映了离散事件特征,对分布式驱动电动汽车控制性能的改善、智能化水平的提高提供了理论研究意义和工程研究价值。     

电动汽车驱动电机故障诊断试验台设计

针对目前电动汽车驱动电机试验台多是用于电机性能测试的现状,设计了用于电动汽车驱动电机典型工况模拟和故障信号采集的试验台;通过NI cRIO控制器、可编程控制器和比例-积分-微分(PID)控制实现被测电机的典型工况模拟,利用NI 9220和NI 9234采集模块完成了被测电机电流、温度、转速、转矩和振动多路故障信号的高速同步采集;基于实验室虚拟仪器集成环境(LabVIEW)平台开发了一套可以实现实时电机控制与信号显示的上位机软件;对被测电机进行负载实验。结果表明,电机控制效果良好,信号采集频率与精度可以满足要求,能够为电动汽车驱动电机的故障诊断和性能优化提供数据基础。     

电动汽车绝缘检测装置

电动汽车绝缘检测装置系国家高新技术研究发展计划(“863”计划)电动汽车重大专项所属子课题的研究成果．常规的汽车采用燃油或者天然气作为动力源，基本不存在高压绝缘问题，而电动汽车是一个复杂的机电一体化产品，其中涉及到强电及绝缘的有：动力电池、电机、充电机、能量回收装置、辅助电池充电装置、以及其它由动力蓄电池供电的装置．这些装置都含有高压设备以及器件，     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

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海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to