共查询到20条相似文献，搜索用时 406 毫秒
1.
Control Strategy and Simulation Study on NiMH Battery Quick Charging for Regenerative Braking of HEV
Based on the result of NiMH battery performance experiments, changing trend of maximal temperature and difference in temperature of HEV NiMH battery in different SOC and different charging current is analyzed. Considering the working situation of HEV NiMH battery and the theory of battery quick charging, a control strategy for NiMH battery quick charging is described which adapts to HEV regenerative braking system based on Mascc law. By Modeling and simulating the process of NiMH battery quick charging with this strategy, constant voltage charge method and constant current charge method, validates this control strategy. 相似文献
2.
In order to increase using time of the batteries, and improve the hybrid electrical vehicles' economical and dynamic performance. By analyzing imbalance instances of the batteries, the battery characteristic mode of batteries imbalance dynamic performance is built, and the energy diffluent charge and discharge modes about controlling batteries imbalance degrees are put forward. Consequently, the energy diffluent charge and discharge controlling strategys of batteries imbalance degrees are advanced, and simulation calculation is processed, good-result is received. 相似文献
3.
For the requirement of building up the battery management system (BMS) of hybrid vehicles(HEVs), the real time measurement and estimation of charge (SOC) of the Ni MH batteries are investigated, because the popular SOC definition is unsuitable under the condition of variable current discharge. The origin of this kind unsuitability are analyzed ,and the characteristics and existing problems of different kinds of SOC measuring methods are compared. On the basis of mentioned above, some corrections are given to the popular SOC definition, and the new conception of SOC is proposed. The corrected definition of SOC is suitable for the real time SOC estimation under the variable current condition of the batteries used in HEVs. Based on the corrected SOC definition, the computational model of the new SOC is built and simulated. Satisfactory result has been obtained from comparisons of the simulating results, which shows that the theoretical model provides a basis for optimizing the adaptation of power system to the hybrid vehicles (HEVs). 相似文献
4.
The efficiency of the 60QNY6.5 battery is studied by testing and theoretical analysis in order to improve the control precision of hybrid electric vehicles (HEVs) and the battery useful life. A rig for testing the Ni MH batteries of HEVs is established. The data from experiments performed on the Ni MH battery are analyzed. Based on the experimental results and the temperature of the batteries, internal resistance and electromotance models of Ni MH batteries are proposed by function fitting methods. The theoretic formula for battery efficiency is deduced by the operational principle of the battery and motor, which provides theoretical basis for dynamic optimizing technology of HEV system controlling strategy. 相似文献
5.
The Kalman filter algorithm can be used to estimate the state of charge (SOC) of power batteries, however, it easily causes divergence due to uncertain of system noise and its estimation performance is affected by model. An adaptive Kalman filter algorithm is adopted to dynamically estimate SOC of lithium iron phosphate batteries for application in electric vehicles. At first, an equivalent circuit model, appropriate for SOC estimation is built after studying battery models. Then some charging and discharging experiments are carried out for parameter identification and the results are verified. At last, the adaptive Kalman filter algorithm is used on this model for on-line SOC estimation under unknown interfering noise. Simulation results show that adaptive Kalman filter method can correct SOC estimation error caused by tiny model error online, and the estimate accuracy is higher than Kalman filter method. Adaptive Kalman filter algorithm can also correct the initial error. Full-cycle test in electric vehicles proves that the algorithm is appropriate for SOC estimation of lithium iron phosphate battery. 相似文献
6.
Focusing on Ni MH batteries used in hybrid electric vehicles (HEV), a simulation analysis of the flow and temperature fields of the cooling structure in existing batteries is carried out using computational fluid dynamics software. The results show that the temperature uniformity is poor. The uniformity of the flow and the temperature fields is improved by adjusting the baffle and battery positions, changing the tilt angle and the distance between the batteries, inserting wind plates and a coating insulation layer. The coating insulation layer achieves the best effect. Further simulation shows that the coating insulation layer method has the best effects. The results provide the design basis for thermal management program of Ni MH batteries in HEV. 相似文献
7.
光储微电网混合储能系统的控制策略及开关优化 总被引：1，自引：0，他引：1
传统光储微电网混合储能系统控制策略将蓄电池视为容量无限大的理想元件,而实际上蓄电池容量有限,当蓄电池剩余电量达到阈值无法正常工作时传统控制策略将不适用。在二阶低通滤波法的基础上提出一种光储微电网混合储能系统的新型控制策略,同时考虑超级电容与蓄电池的剩余电量,根据储能元件的荷电状态调整储能元件输出电流参考值,维持储能元件剩余电量,但在极端天气情况下,仍需与储能元件保护开关相配合。由于采用传统储能元件保护开关的储能系统需独立的充放电电路,存在成本较高、充放电不连续等问题,因此,对储能元件的保护开关进行了改进,利用开关与二极管并联使其具有4种工作状态,在储能元件剩余电量达到阈值时,可自动恢复电量,降低了成本,提高了并网输出电能质量。最后结合新型控制策略与改进的保护开关,提出整体的混合储能系统控制方案,并用Matlab/Simulink对其进行仿真验证,结果证明了所提方法的正确性与可行性。 相似文献
8.
This paper studies the determination methods offuraldehyde and compares them with each other in a furaldehyde-benzenesample system that contains less than 10% of furaldehyde.The recentChinese national standard method is that of hydroxylamine(GB 1926-80).This method has an error approximately greater than 5%,and it has moresteps and is time-consuming.The Nicolet DX quantitative analysis packagecauses even greater error,while FTIR method has errors less than 5%by selecting proper baselines and drawing a work curve.FTIR methodis simple,quick and nondestructive,and needs only few amounts ofsamples.It's suitable to the samples of the system of the experiment. 相似文献
9.
非破坏评价黄瓜的营养成分 总被引：8，自引：0，他引：8
用近红外光谱法非破坏分析黄瓜中的维生素Ｃ、还原糖、干物重三种成分，与国际法相比，其相关系数分别为０．９９３２、０．９９３０、０．９８１６，标准误差为０．３６８ｍｇ／１００ｇ、０．０６８％和０．０８５％，说明两种方法有着相似的准确性和精密度，而近红外光谱法分析效率可提高上百倍，且不需要任何前处理，也不用化学试剂，分析后的黄瓜样品仍可食用或作商品出售。既适用于大批量样品的分析测定，又为品质育种和种质资 相似文献
10.
RAN Zhen-ya~ 《保鲜与加工》2004,(6):25-29
The powertrain of a new type of zero emission electric vehicle is researched, which powered primarily by air-breathing proton exchange membrane (PEM )fuel cells with gaseous hydrogen as fuel,and with Lead-acid battery as assistant power.The fuel cell system provides power for the vehicle while the vehicle travel at a cruising speed,and the exceed power will charge for battery.The fuel cell and the battery system will together provide power to the vehicle during periods of peak power demand such as vehicle acceleration or traveling at a high constant speed.At the same time, the powertrain parameter of this fuel cell vehicle are matched reasonably.At last, the dynamic of an electric vehicle is simulated, and the result shows that the dynamic performance perfectly meets the need of the design target. 相似文献
11.
X射线荧光光谱法测定哈尔滨城郊菜地土壤重金属 总被引：5，自引：0，他引：5
本文以哈尔滨市城郊菜地土壤为例,通过野外调查和室内分析对哈尔滨城郊菜地土壤的理化性质及重金属含量进行研究。在用X射线荧光光谱法测定沉积物中重金属时,为检测实验分析的可靠性,随机抽取了12个样品做5次重复实验,测得As、Cr、Cu、Pb、Zn的相对标准偏差分别为0.005％、0.006％、0.013％、0.003％ 和0.011％,结果表明X射线荧光法测定样品,不需对固体样品进行消化处理,操作简便,可以同时测定多种元素,效率较高,而且是一种非破坏性的分析方法,样品可重复利用。 相似文献
12.
There are more than two power source in Hybrid Electrical Vehicle(HEV). By using of assist accelerating, power regeneration, Idle stop and power management, HEV gains more acceleration performance and more fuel economy and better gas emission than Conventional Vehicle(CV). With Integrated Starter and Generator(ISG) as a auxiliary power source, batteries and battery control module and power manage module as a Load leveling Device (LLD), two prototype HEV separately equipped Manual Transmission (MT) and Continuously Variable Transmission (CVT) was successfully developed. 相似文献
13.
One of the important technical problems of various implantable devices concerns effectively supplying sufficient energy to allow devices to work for extended periods, steadily and reliably. Presently, batteries and magnetic induction are only power supplies widely used in clinics. Because the capability of batteries is limited, implantable devices have shorter lives and low energy transfer efficiencies. We presented a means of transferring electrical energy into rechargeable batteries in implantable device by using volume conduction of biological organisms. An energy transfer model of volume conduction was created using ANSYS V10. We analyzed the energy transfer efficiency from simulation results and provide reference for further study of energy transfer of volume conduction. 相似文献
14.
俞漪 《农产品加工．学刊》2012,(10):138-140,148
分析了食品微生物检测快速测试片法与国标法的差异性。制备适宜的标准菌悬液,使用快速测试片标准法和国标法分别检测微生物,比较分析2种方法的差异性。所得试验数据通过统计学比较,t值均小于t_(0.05(2)),认为测试片标准法和国标法无显著性差异。 相似文献
15.
应用竞争酶联免疫法(ELISA)能够快速对动物性食品中的恩诺沙星残留进行检测筛选。与其他检测方法相比,ELISA具有适用范围宽、样品预处理简单、批处理量大、检测速度快、准确性高和重复性强的特点,特别适用于基层大规模筛选和现场监控。 相似文献
16.
Research on Current Situation and Trend of Control Strategies for Hybrid Electric Vehicles 总被引：1，自引：0，他引：1
The vehicle's driving performances is determined by the control strategies and constructions of hybrid electric vehicles (HEV). The constructions of HEV are classified according to the change of state of charge of battery pack, and a study on current situation and trend of control strategies for HEV is presented in this paper. The research indicated that the current control strategies for HEV are not perfect and need further optimization. The control strategies should realize the optimum match among engine, motor, battery and transmission according to the characteristics of each component and vehicle's driving conditions. Many aspects including the fuel economy, emission, the life of battery pack, drivability, the reliability of each component and HEV's manufacture cost should be considered in the control strategies. A study on the control strategies and its optimization that take account of the aspects mentioned above is a work emphasis in the future. This paper also points out the PHEV equipped with small motor, small engine and continuously variable transmission is an ideal system construction for getting optimal fuel economy, lower emissions, steady drivability, lower manufacture cost and HEV's mass. 相似文献
17.
Starch determination in plant matter is necessary because of the importance of the carbohydrate pool in combination of the nitrogen pool in crop growth and development. This analysis is complicated in vegetative materials by contamination with non-starch containing material. Starch is not a homogenous material, so the content of amylose and amylopectin varies from the different growth stages and from crop to crop. Therefore standard methods of starch estimation give no exact result. The method described here based on a pretreatment of the plant material with dilute alkali before hydrolysis with amyloglucosidase and the estimation of the glucose content. Therefore this procedure was first tested on amylose, amylopectin, soluble starch, three commercially available starches, and was then applied to vegetative rape material. Recoveries of amylose and three commercial starches were between 98 and 100 % after a additional ultrasonic treatment. The method is advantageous because it is simple, quick and reproducible. 相似文献
18.
19.
烟草不同组织总RNA的提取方法初探 总被引：2，自引：0，他引：2
【研究目的】寻找烟草各个组织总RNA最佳的提取方法。【方法】以烟草K326的根、茎、叶、蕾、花和种子为材料,分别采用试剂盒法、Trizol法和CTAB法提取烟草6个组织总RNA进行对比。【结果】烟草不同组织总RNA提取方法有所不同,试剂盒法和Trizol法只能提取出根、茎、叶、蕾和花的总RNA,而不能提取种子总RNA;CTAB法能提取出6个组织的RNA。3种方法提取的RNA质量好,均能满足RT-PCR以及后续实验的要求。【结论】试剂盒法较Trizol法和CTAB法简单、快捷,适合于烟草除种子以外其余组织总RNA快速提取,CTAB法适合烟草所有组织总RNA提取。 相似文献
20.
用垂直板和等电聚焦丙烯酰胺过氧化物同功酶电泳方法对14个大白菜杂交品种进行了纯度鉴定,并同时在田间进行重复检测。二者纯度结果相关系数r=0.87,表明电泳鉴定和田间检验结果间存在着显著的正相关关系。因此应用同功酶电泳技术鉴定大白菜杂交种纯度是可行的,可作为鉴定真伪杂种的一种新方法。 相似文献