共查询到19条相似文献,搜索用时 93 毫秒
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针对蓄电池-超级电容双能量源存储系统能量管理建模问题,对双能量源纯电动汽车能量管理系统的结构和工作过程进行了分析。分析了蓄电池-超级电容纯电动汽车的四种工作模式,车辆行驶中的阻力功率,能量管理系统的功率以及运行约束条件,对能量管理系统进行了建模研究,给出了双能量源纯电动汽车能量管理系统数学模型,并提出了能量管理控制策略。 相似文献
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铁路客车发生碰撞时,最先接触的端部容易损坏,并沿着车体向客室传递,给乘客带来了很大安全隐患。文中在接触碰撞的端部设计一种新型吸能结构装置,通过这种吸能装置可以吸收碰撞产生的能量。通过吸能材料性能和结构的理论分析,冲击产生的能量转变为吸能装置的变形,产生了极大的缓冲。通过研究表明该吸能装置具有良好吸能效果,实现了对乘客的良好保护。 相似文献
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利用源信号到达两传感器间具有不同能量衰减比的特性,提出了一种新的源数估计方法,解决了因传感器数量不足而无法准确估计源信号数目的问题。首先,利用线性时频变换方法得到两观测信号在频域的能量分布,然后,计算能量散点图中对应角度上的能量总和;最后,通过峰值检测法实现源数目的自动检测。通过理论分析、仿真和实验,证明了该方法的有效性。本方法为盲源分离算法处理振动、噪声信号,提供了可靠的先验信息。 相似文献
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数控机床多能量源的动态能耗建模与仿真方法 总被引:3,自引:0,他引:3
机床能量消耗过程的评估和分析是机床能效优化研究的基础。现有研究提出的机床能耗模型主要是静态能耗模型,少数对机床动态性能耗的研究又主要集中在机床运行状态的动态性的建模,缺乏对机床能量源特别是数控机床多能量源的动态性能耗的研究。针对数控机床能量源多、加工任务及加工参数动态变化等特点,提出了一种数控机床多能量源的动态能耗建模与仿真方法。对数控机床能耗过程的动态性进行分析;在此基础上,结合面向对象着色赋时Petri网(Colored timed object-oriented Petri net,CTOPN)和虚拟部件方法建立数控机床多能量源动态能耗模型,其中CTOPN模型用于描述数控机床能耗过程机床和多能量源运行状态的动态特性,虚拟部件方法用于描述数控机床多能量源受加工参数影响的动态特性;通过CTOPN中"变迁"蕴含的信息来驱动虚拟部件模型实现对数控机床多能量源的动态能耗特性的建模。案例分析结果证明了该方法的可行性,上述模型可为数控机床动态能耗的预测、综合的能耗特性分析以及定量的能耗影响因素分析提供一种基础支持,具有较广阔的应用前景。 相似文献
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在理论分析的基础上,提出一种新型的适用于电压源桥式逆变电路的无源无损耗吸收能量回馈结构.详细描述了其拓扑特点、工作原理.在吸收结构基础上,提出一种无源无损耗吸收能量回馈方法. 相似文献
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在理论分析的基础上,提出一种新型的适用于电压源桥式逆变电路的无源无损耗吸收能量回馈结构.详细描述了其拓扑特点、工作原理.在吸收结构基础上,提出一种无源无损耗吸收能量回馈方法. 相似文献
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综述了近年来有关汽车节能、环保技术的研究现状,给出了城市公交车可利用能量源的种类和分类方法,分析了各种能量源的开发现状及应用前景,展望了今后研究的发展方向,为今后的相关研究工作提供参考。 相似文献
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车辆乘坐室内低频噪声声源识别研究 总被引:2,自引:1,他引:1
提出了一种用于车内低频噪声声源识别的理论分析方法。该方法摆脱了对试验的依赖,可用于车身结构低噪声优化设计(或修改)的迭代求解过程。分别采用所提方法和相关分析法,对某型国产轿车乘坐室内驾驶员右耳位置处的低频噪声主要来源进行识别,得出了一致的结论。 相似文献
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动力电池作为新能源纯电动汽车的动力源,其能量密度与整车的续驶里程及安全性等密切相关,而锂离子电池具有高能量密度和长寿命等特点,是当前新能源汽车动力电池的主流选择。基于锂离子电池发展史和我国第1~48批《免征车辆购置税的新能源汽车车型目录》中2000余款纯电动乘用车的锂离子动力电池能量密度数据,系统研究了锂离子动力电池能量密度演变趋势,回顾了我国锂离子动力电池能量密度的提升历程及其对推动新能源汽车发展起到的良好作用。在此基础上,从电极材料、电池工艺和成组结构等3个方面,剖析了锂离子动力电池能量密度提升技术方案的优势与不足;并从电池能量密度和安全性的关联性出发,总结了高能量密度电池在设计、制造和使用等全生命周期中的安全技术,展望了锂离子动力电池未来的发展趋势,为新能源汽车行业未来的健康发展提供参考。 相似文献
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This study presents calculations on the global fuel energy consumption used to overcome friction in passenger cars in terms of friction in the engine, transmission, tires, and brakes. Friction in tribocontacts was estimated according to prevailing contact mechanisms such as elastohydrodynamic, hydrodynamic, mixed, and boundary lubrication. Coefficients of friction in the tribocontacts were estimated based on available information in the literature on the average passenger car in use today, a car with today’s advanced commercial tribological technology, a car with today’s best advanced technology based upon recent research and development, and a car with the best technology forecasted in the next 10 years. The following conclusions were reached:
- •In passenger cars, one-third of the fuel energy is used to overcome friction in the engine, transmission, tires, and brakes. The direct frictional losses, with braking friction excluded, are 28% of the fuel energy. In total, 21.5% of the fuel energy is used to move the car.
- •Worldwide, 208,000 million liters of fuel (gasoline and diesel) was used in 2009 to overcome friction in passenger cars. This equals 360 million tonne oil equivalent per year (Mtoe/a) or 7.3 million TJ/a. Reductions in frictional losses will lead to a threefold improvement in fuel economy as it will reduce both the exhaust and cooling losses also at the same ratio.
- •Globally, one passenger car uses on average of 340 l of fuel per year to overcome friction, which would cost 510 euros according to the average European gas price in 2011 and corresponds to an average driving distance of 13,000 km/a.
- •By taking advantage of new technology for friction reduction in passenger cars, friction losses could be reduced by 18% in the short term (5–10 years) and by 61% in the long term (15–25 years). This would equal worldwide economic savings of 174,000 million euros and 576,000 million euros, respectively; fuel savings of 117,000 million and 385,000 million liters, respectively; and CO2 emission reduction of 290 million and 960 million tonnes, respectively.
- •The friction-related energy losses in an electric car are estimated to be only about half those of an internal combustion passenger car.
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Particle size distribution and particle number concentration from diesel engines are subjects of significant environmental
concerns especially in the EU. A few years ago, the UN-ECE PMP proposed a method for measuring particle emissions in the diluted
exhaust of internal combustion engine vehicles, which has become a key method used in new dilution systems and sampling condition.
This paper describes the effects of parameters such as condensation particle counter (CPC) according to test procedures, test
fuel and vehicle test mode, including NEDC and CVS-75 mode. The main results obtained from this study can be summarized as
follows: (1) Periodic calibration of the CPC system is essential because the long-term usage of a CPC leads to an underestimation
in the measurements of small particles. (2) Particle emissions measured by the UN-ECE PMP method were found to exhibit comparable
repeatability as compared to other regulated emissions. (3) In particle number concentration emitted from different-fueled
vehicles, the sources of particle emissions in an ascending order of magnitude are as follows: DPF equipped diesel passenger
vehicles, gasoline and LPG fueled vehicles, and DPF unequipped diesel passenger vehicles. Also, we found that the particle
numbers of DPF equipped diesel passenger vehicles, gasoline and LPG-fueled vehicles can meet the EU regulation limit (<6.0×1011#/km), while DPF unequipped diesel passenger vehicles do not meet the EU limit. 相似文献
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以扶梯为例,根据动力学的基本原理,推导了扶梯制动力矩、制停距离与负载变化、系统运动部件固有总质量之间的关系公式,描述了扶梯主机高速轴转动惯量对扶梯制动能量、制停距离、制动力矩的调节作用,为变载恒转矩制动系统性能的优化,特别是如何满足变载乘客运输系统的制动部件的规范要求和配置特点,提供参考性意见。 相似文献