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101.
This paper presents a fuel efficient control strategy for a group of connected hybrid electric vehicles (HEVs) in urban road conditions. A hierarchical control architecture is proposed in this paper for every HEV, where the higher level and the lower level controller share information with each other and solve two different problems that aim at improving its fuel efficiency. The higher level controller of each HEV is considered to utilize traffic light information, through vehicle to infrastructure (V2I) communication, and state information of the vehicles in its near neighborhood, via vehicle to vehicle (V2V) communication. Apart from that, the higher level controller of each HEV uses the recuperation information from the lower level controller and provides it the optimal velocity profile by solving its problem in a model predictive control framework. Each lower level controller uses adaptive equivalent consumption minimization strategy (ECMS) for following their velocity profiles, obtained from the higher level controller, in a fuel efficient manner. In this paper, the vehicles are modeled in Autonomie software and the simulation results are provided in the paper that shows the effectiveness of the proposed control architecture.  相似文献   
102.
Despite the rapid market penetration of hybrid vehicles (HVs), their usage and contributions to environmental protection have not been examined by vehicle traveling data. In this paper, we analyzed Japan’s used car market data to understand how HVs are used on the street. We find GV drivers with high travel demand switched from GVs to HVs during the transition period. Despite HV owners driving much longer distances than conventional gasoline vehicle (GV) owners, they emit less carbon dioxide (CO2) emissions, owing to better fuel economy. We also find that HV owners spend roughly the same amount of money annually as GV owners. However, the per-kilometer travel cost of HVs is much lower than that of GVs even if the depreciation cost of the vehicle and vehicle related taxes are included in the analysis.  相似文献   
103.
首先介绍一汽混合动力商用车的研发背景、整车概念描述、整车电气系统配置。然后阐述如何进行电气系统设计,其中分为电气系统供电电路设计和控制器通信系统的通信电路设计。最后总结混合动力商用车电气系统设计的要点,并对混合动力商用车进行展望。  相似文献   
104.
The suitability of an electric vehicle of a given range to serve in place of a given conventional vehicle is not limited by the daily travel over distances within that that range, but rather by the occasional inconvenience of finding alternative transport for longer trips. While the frequency of this inconvenience can be computed from usage data, the willingness of individual users to accept that replacement depends on details of available transportation alternatives and their willingness to use them. The latter can be difficult to assess. Fortunately, 65% of US households have access to the most convenient alternative possible: a second car. In this paper we describe an analysis of prospective EV acceptance and travel electrification in two-car households in the Puget Sound region. We find that EVs with 60 miles of useful range could be acceptable (i.e. incur inconvenience no more than three days each year) to nearly 90% of two-car households and electrify nearly 55% of travel in those households (32% of all travel). This compares to 120 miles range required to achieve the same fraction of electrified travel via one-for-one replacement of individual vehicles. Even though only one third of personal vehicles in the US may be replaced in this paradigm, the ‘EV as a second-car’ concept is attractive in that a significant fraction of travel can be electrified by vehicles with modest electric range and virtually no dependence on public charging infrastructure.  相似文献   
105.
Despite the recent commercial success of hybrid, plug-in hybrid and electric vehicles their market share is still insufficient to produce either a significant impact on energy consumption on a global basis or a profitable automotive segment. In this context, the possibility of upgrading conventional vehicles to hybrid electric vehicles is gaining increasing interest.To this aim this paper investigated and modelled the intention to install an after-market hybridization solar-kit (HySolarKit) in order to ascertain the main behavioural determinants of the choice process and set up an operational model with which to estimate the market potential of such technology. In particular, two behavioural stages of the choice process were analysed and modelled: (i) the intention to adopt the HySolarKit; (ii) the choice to install the HySolarKit. Both issues were addressed through ad hoc stated preference surveys carried out in two different Italian cities, and through the specification and the calibration of discrete choice models based on the behavioural paradigm of random utility theory. Different modelling solutions (homoscedastic and heteroscedastic) were compared in terms of goodness-of-fit and sensitivity to level-of-service attributes. The results showed the technological potential of the HySolarKit, and that both behavioural stages may be effectively modelled through random utility theory. Estimation results allowed an interpretation of the main determinants of the investigated phenomena, making it possible to quantify the potential effects and the concerns towards such a green solution, and making it possible to draw up operative marketing strategies. In particular, the intention to adopt the kit mainly depends on socio-economic factors as well as activity-related and attitudinal attributes, whereas the probability of installing the kit is greatly affected, to the same extent, by installation cost, the charging cost and the weekly mileage driven.  相似文献   
106.
Public transit structure is traditionally designed to contain fixed bus routes and predetermined bus stations. This paper presents an alternative flexible-route transit system, in which each bus is allowed to travel across a predetermined area to serve passengers, while these bus service areas collectively form a hybrid “grand” structure that resembles hub-and-spoke and grid networks. We analyze the agency and user cost components of this proposed system in idealized square cities and seek the optimum network layout, service area of each bus, and bus headway, to minimize the total system cost. We compare the performance of the proposed transit system with those of comparable systems (e.g., fixed-route transit network and taxi service), and show how each system is advantageous under certain passenger demand levels. It is found out that under low-to-moderate demand levels, the proposed flexible-route system tends to have the lowest system cost.  相似文献   
107.
This paper proposes a mechanical solution to save fuel by shutting down an internal combustion engine whenever it is unnecessary for propulsion, e.g., when a vehicle is waiting for traffic lights. The engine and vehicle are restarted using the energy that is stored in a flywheel. Two additional clutches are needed to enable appropriate power flow from the flywheel to the engine and vehicle. This complicates the powertrain dynamics in that the number of degrees of freedom changes due to clutch operations. Therefore, a hybrid control strategy, which is treated as a top-level controller, is introduced to deal with this finite-state mechanical system. At the lower level, the engine and clutches are controlled in a coordinated manner such that the vehicle is launched according to the driver's demands. Using a comprehensive powertrain simulation package, the proposed controller is evaluated numerically.  相似文献   
108.
本文介绍对转桨吊舱推进器的结构特点,综合评估吊舱式混合电力推进系统(hybrid CRP podded propulsion)性能,得出其在机舱布置、燃油消耗量、投资成本等方面具有优良性能的结论。  相似文献   
109.
Supply chain management has a tremendous impact on the success of a company. One of the critical issues for gaining competitive advantages for companies is improving supply chain performance. Most studies about the application of Data Envelopment Analysis (DEA) Supply chain models do not identify the benchmarking units for inefficient supply chains. On the other, measuring the short run and long run of the supply chain efficiency is another challenge for decision makers in supply chain management. Hence, we propose a methodology of DEA for measuring of the supply chain. We integrated two approaches as special cases of the hybrid model and compare the short and long run strategies of supply chain and can be identified benchmarking.  相似文献   
110.
以某款正在设计的混合动力车型的电驱动变速器齿轮为研究对象进行噪声优化设计.分析了变速器齿轮噪声产生机理和影响因素,介绍了电驱动变速器齿轮不同于传统变速器齿轮的噪声设计要求和方法,并依据该要求和方法进行了齿轮微观修形设计和优化.实车噪声测试结果表明,仿真结果可靠且能达到混合动力车辆的NVH要求.  相似文献   
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