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991.
Design of an energy management strategy for parallel hybrid electric vehicles using a logic threshold and instantaneous optimization method 总被引:2,自引:0,他引:2
Y.- J. Huang C.- L. Yin J.- W. Zhang 《International Journal of Automotive Technology》2009,10(4):513-521
A novel parallel hybrid electric vehicle (PHEV) configuration consisting of an extra one-way clutch and an automatic mechanical
transmission (AMT) is taken as the study subject of this paper. An energy management strategy (EMS) combining a logic threshold
approach and an instantaneous optimization algorithm is developed for the investigated PHEV. The objective of this EMS is
to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing engine fuel economy
and maintaining the battery state of charge (SOC) in its rational operation range at all times. Under the MATLAB/Simulink
environment, a computer simulation model of the studied PHEV is established using the bench test results. Simulation results
for the behavior of the engine, motor, and battery illustrate the potential of the proposed control strategy in terms of fuel
economy and in keeping the deviations of SOC at a low level. 相似文献
992.
S. Y. Kim H. C. Choi W. J. Won S. Y. Oh 《International Journal of Automotive Technology》2009,10(1):103-113
Because the overall driving environment consists of a complex combination of the traffic Environment, Vehicle, and Driver
(EVD), Advanced Driver Assistance Systems (ADAS) must consider not only events from each component of the EVD but also the
interactions between them. Although previous researchers focused on the fusion of the states from the EVD (EVD states), they
estimated and fused the simple EVD states for a single function system such as the lane change intent analysis. To overcome
the current limitations, first, this paper defines the EVD states as driver’s gazing region, time to lane crossing, and time
to collision. These states are estimated by enhanced detection and tracking methods from in- and out-of-vehicle vision systems.
Second, it proposes a long-term prediction method of the EVD states using a time delayed neural network to fuse these states
and a fuzzy inference system to assess the driving situation. When tested with real driving data, our system reduced false
environment assessments and provided accurate lane departure, vehicle collision, and visual inattention warning signals. 相似文献
993.
994.
T. Fang R. E. Coverdill C. -F. F. Lee R. A. White 《International Journal of Automotive Technology》2009,10(3):285-295
In this paper, the influence of injection parameters on the transition from Premixed Charge Combustion Ignition (PCCI) combustion to conventional diesel combustion was investigated in an optically accessible High-Speed Direct-Injection (HSDI) diesel engine using multiple injection strategies. The heat release characteristics were analyzed using incylinder pressure for different operating conditions. The whole cycle combustion process was visualized with a high-speed video camera by simultaneously capturing the natural flame luminosity from both the bottom of the optical piston and the side window, showing the three dimensional combustion structure within the combustion chamber. Eight operating conditions were selected to address the influences of injection pressure, injection timing, and fuel quantity of the first injection on the development of second injection combustion. For some cases with early first injection timing and a small fuel quantity, no liquid fuel is found when luminous flame points appear, which shows that premixed combustion occurs for these cases. However, with the increase of first injection fuel quantity and retardation of the first injection timing, the combustion mode transitions from PCCI combustion to diffusion flame combustion, with liquid fuel being injected into the hot flame. The observed combustion phenomena are mainly determined by the ambient temperature and pressure at the start of the second injection event. The start-of-injection ambient conditions are greatly influenced by the first injection timing, fuel quantity, and injection pressure. Small fuel quantity and early injection timing of the first injection event and high injection pressure are preferable for low sooting combustion. 相似文献
995.
The methodology to obtain the non-linear roll damping from decay tests is very old. It has been proposed by Froude in the 19th century and used from then on. Behind it there is a quadratic model [θ│θ│] for the damping and a subsequent equivalent linearization. Probably all model basin in the world follows this approach to assess the damping from a decay test. This is well documented and so is the methods to get the p1-p2 coefficients. This is very general in the sense that in principle,it could be applied t... 相似文献
996.
Among disaggregate vehicle ownership models, which model the number and/or type of vehicles owned at the household level, one can distinguish holdings models, which deal with the (optimal) household fleet at a single point in time, and transactions models. The latter type of model explains changes to the household fleet, such as replacement and disposal. The paper describes previous attempts at such dynamic models and sketches how a vehicle transactions model could look (as an example we discuss an application to The Netherlands). This includes discussions of transaction probabilities, two-stage budgeting, introducing vehicle quality in the utility functions, and the envisaged model structure and data it could use. 相似文献
997.
Margarida C. Coelho H. Christopher Frey Nagui M. Rouphail Haibo Zhai Luc Pelkmans 《Transportation Research Part D: Transport and Environment》2009,14(2):91-99
This paper assess whether a real-world second-by-second methodology that integrates vehicle activity and emissions rates for light-duty gasoline vehicles can be extended to diesel vehicles. Secondly it compares fuel use and emission rates between gasoline and diesel light-duty vehicles. To evaluate the methodology, real-world field data from two light-duty diesel vehicles are used. Vehicle specific power, a function of vehicle speed, acceleration, and road grade, is evaluated with respect to ability to explain variation in emissions rates. Vehicle specific power has been used previously to define activity-based modes and to quantify variation in fuel use and emission rates of gasoline vehicles taking into account idle, acceleration, cruise, and deceleration. The fuel use and emission rates for light-duty diesel vehicles can also be explained using vehicle specific power -based modes. Thus, the methodology enables direct comparisons for different vehicle fuels and technologies. Furthermore, the method can be used to estimate average fuel use and emission rates for a wide variety of driving cycles. 相似文献
998.
Nathan C. Shahan 《经济导报》2009,(3):49-53
随着美国保德河和圣胡安盆地裸眼煤层甲烷项目的成功开发,20世纪90年代末,澳大利亚的经营者们开始钻探裸,眼垂直并。此后的几年间,澳大利亚早期煤层甲烷经营者凭借着自身的聪明才智、积极创造和灵活变通,使气井设计取得了世界上其它任何煤层甲烷开发项目中前所未有的进展。这些经营者目前正在实施结构复杂的多层多边地表内层(SIS)气井设计,这种设计有望开采全球的煤层甲烷储层。 相似文献
999.
1000.