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481.
丁彦侃  洪超  郑建 《船舶工程》2017,39(6):46-48
升降系统的同步性能是电动齿轮齿条升降系统的一项重要技术指标,是桩腿和平台顺利实现升降的保证。本文以一套电动齿轮齿条式升降系统样机为实验对象,并设计了基于PROFIBUS-DP现场总线的PLC同步控制系统,针对电机同步控制系统的参数时变、非线性以及容易受负载扰动等特点,采用一种带PI控制的位移偏差耦合控制算法,在组态的上位机上记录平台的实验数据,然后用MATLAB软件分析实验数据。实验结果表明,系统安全性可靠性较高,同步性能较好,收敛速度快且结构简单,能够用于指导实际平台的同步控制设计。  相似文献   
482.
This study addresses two problems in the context of battery electric vehicles (EVs) for intercity trips: the EV routing problem and the EV optimal charging station location problem (CSLP). The paper shows that EV routing on the shortest path subject to range feasibility for one origin–destination (O–D) pair, called the shortest walk problem (SWP), as well as a stronger version of the problem – the p-stop limited SWP – can be reduced to solving the shortest path problem on an auxiliary network. The paper then addresses optimal CSLPs in which EVs are range feasible with and without p-stops. We formulate the models as mixed-integer multi-commodity flow problems on the same auxiliary network without path and relay pattern enumeration. Benders decomposition is used to propose an exact solution approach. Numerical experiments are conducted using the Indiana state network.  相似文献   
483.
Widespread adoption of electric vehicles (EVs) may contribute to the alleviation of problems such as environmental pollution, global warming and oil dependency. However, the current market penetration of EV is relatively low in spite of many governments implementing strong promotion policies. This paper presents a comprehensive review of studies on consumer preferences for EV, aiming to better inform policy-makers and give direction to further research. First, we compare the economic and psychological approach towards this topic, followed by a conceptual framework of EV preferences which is then implemented to organise our review. We also briefly review the modelling techniques applied in the selected studies. Estimates of consumer preferences for financial, technical, infrastructure and policy attributes are then reviewed. A categorisation of influential factors for consumer preferences into groups such as socio-economic variables, psychological factors, mobility condition, social influence, etc. is then made and their effects are elaborated. Finally, we discuss a research agenda to improve EV consumer preference studies and give recommendations for further research.

Abbreviations: AFV: alternative fuel vehicle; BEV: battery electric vehicle; CVs: conventional vehicles; EVs: electric vehicles; FCV: fuel cell vehicle; HCM: hybrid choice model; HEV: hybrid electric vehicle (non plug-in); HOV: high occupancy vehicle; MNL: MultiNomial logit; MXL: MiXed logit model; PHEV: plug-in hybrid electric vehicle; RP: revealed preference; SP: stated preference.  相似文献   

484.
应用汽车动力学理论,以1/4汽车悬架模型为研究对象,用调节减振器的阻尼系数法,建立了二自由度电动赛车的半主动悬架最优控制模型,利用编制的路面谱作为激励输入进行了仿真,并与被动悬架性能进行了对比。结果表明,半主动悬架在车身垂直振动加速度、悬架动行程、轮胎形变量的改善度分别为31.3%、21.4%、12.6%,使车身的振动被控制在某个范围之内,大大提高电动赛车在行驶过程中的平顺性。  相似文献   
485.
In this paper we discuss the effectiveness, efficiency and feasibility of policy measures that cities may adopt to stimulate the uptake and use of electric vehicles. Our analysis is based on an expert workshop in which municipal policy-makers used a group decision room system to exchange their experiences with electric vehicle related policies. We distinguish six categories of measures: supporting citizens and businesses, supporting charging-infrastructure build up, regulatory measures, raising awareness, government as lead user, and governing the transition with other levels of government. We find two feasible policy mixes of effective and efficient measures, one for cities that strive to be among the global frontrunners and one of no-regret policies that any city should adopt, if it wants to stimulate electric mobility.  相似文献   
486.
文章以某纯电动客车为研究对象,根据城市-郊区道路条件,驱动电机和电动客车整备参数已定,满足动力性能前提,以两档变速器传动比为变量,利用人群搜索算法(SOA)找到与电机相匹配的传动比,优化能量利用率,提出一种优化设计思路,并利用仿真软件进行仿真分析。仿真结果表明,此设计优化思路为两档纯电动客车设计出最优的传动比,满足道路行驶要求,能量利用率优异。  相似文献   
487.
为解决车用锂离子动力电池在高强度工作过程中电池温度过高以及电池组温均性差等问题,需要对电池组设计合理的电池热管理系统(BTMS),以此提升电池组的冷却性能.首先阐述了热管理系统的常见冷却方式,分析了各种冷却方式之间的优缺点.随后针对应用最为广泛且最易实现的空气冷却方式,从冷却空气流型、电池排布方式、电池间距、冷却空气流...  相似文献   
488.
陈树华  郭宝强 《天津汽车》2009,(8):45-47,59
可编程序控制器(PLC)是一种新型和通用的自动控制装置,但不同品牌的PLC梯形图表述方式有所差别。针对看不懂梯形图的购买者和不会对PLC进行编程的电气维护人员,文章以某公司汽车生产线电气系统的故障检排为例,阐述了由PLC控制的各种电气设备的维护与保养方法。指出PLC处理复杂控制系统的能力远远超过继电器,而且PLC电控设备比继电器电控设备的养护方法更容易。  相似文献   
489.
在电动汽车性能提高并逐步迈向产业化的过程中,提高能量的储备与利用率是迫切需要解决的。超级电容器是一种介于传统电容器和蓄电池之间的新型储能元件,以其优异的功率特性在电动汽车行业的应用日益受到重视.文章介绍了超级电容器的基本原理及特点,阐述了超级电容器在电动汽车上的应用状况及应用中面临的主要问题,指出超级电容器在能量密度和功率密度方面还有待大幅度提高,特别是提高价格竞争力。  相似文献   
490.
The electric power steering (EPS) system is designed to reduce the effort exerted by driver on the steering wheel. One of the most common and critical failures of EPS is the soft-disability of the torque sensor or the loss of its signal, which leads to the instant shutdown of the EPS system while turning and causes serious traffic accidents. In this paper, a novel controller based on the self-alignment torque (SAT) estimation was designed to remedy the soft-disability of EPS system. After the SAT estimation method was verified by the empirical Magic Formula (MF) tire model, the remedy control strategy based on the SAT estimation was developed and evaluated by simulations under step and sinusoidal inputs. To further evaluate the performance of the controller on a real vehicle, experiments on a real EPS system were implemented under step and sinusoidal inputs. The results of simulation and experiment using the controller based on estimated SAT showed this controller to be feasible and capable of eliminating the abrupt reaction torque increment caused by shutdown of EPS and of remedying the soft-disability of EPS system under common input signals.  相似文献   
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