Development and experimental validation of a novel hybrid powertrain with dual planetary gear sets for transit bus applications

Given that energy conservation and environmental protection are two important goals for the automotive industry, the application of a hybrid electric powertrain can improve vehicle energy efficiency while decreasing fuel consumption and engine emissions. Planetary gear-based power-split hybrid powertrains have become widely used in passenger vehicles, but remain rarely employed on transit buses. This study proposes a novel hybrid powertrain based on two planetary gear sets(CHS) and presents its operating principles along with development of a control strategy for the powertrain. The CHS hybrid powertrain operates in electric mode when the driving power demand is low, and changes to a hybrid electric mode according to the power-split principle of the planetary gear set. To validate the feasibility of the designed CHS hybrid powertrain, a prototype transit bus equipped with the designed hybrid powertrain system was built, and the operating characteristics of the system were analyzed through a performance test conducted on a chassis dynamometer. Compared with a conventional powertrain, the CHS hybrid powertrain can reduce fuel consumption by 39%. Thus, the CHS hybrid powertrain is a good solution for heavy-duty applications such as hybrid transit buses because of its simple structure and excellent fuel efficiency.     

混联式混合动力汽车动力系统参数匹配的研究

混合动力汽车动力总成参数的合理匹配是混合动力汽车产品开发的重要前提和基础性工作.在对混联式混合动力汽车动力总成结构和整车控制策略分析的基础上,分别进行发动机、电动机和蓄电池等动力总成部件的选型和参数设计,并对传动系统进行参数设计.针对发动机、永磁同步电动机和镍氢蓄电池的工作特性建立模型,并基于NEBC工况进行仿真,得出发动机扭矩、电动机扭矩和蓄电池荷电状态的变化曲线.结果表明,混联式混合动力汽车动力系统的参数匹配合理.     

一体化起动发电机并联混合动力汽车发动机稳态优化控制与仿真

针对基于发动机效率最优化的传统混合动力汽车发动机稳态优化控制没有考虑动力总成系统其他部件的效率的问题,提出了以混合动力汽车整个动力总成系统能量转换效率最优化为目标的发动机稳态优化控制策略并经仿真验证,在中国乘用车城区瞬态循环下,与传统控制策略相比燃油经济性改善了3.9%。     

微电网混合储能系统研究

针对微电网中传统蓄电池储能系统循环寿命短、电压波动大、功率密度低等问题,提出了一种由蓄电池和超级电容器构成的混合储能系统及其控制方法。充分利用两种储能元件的优势,通过设计均压控制策略、功率控制、V/f控制等手段,实现了各蓄电池和超级电容器单体的均压控制;最后建立Matlab/Simulink模型对系统进行仿真。结果表明,该方法减缓了电网负载波动时蓄电池的电流波动,减小了直流母线的电压波动,验证了该方法的可行性。     

基于Cruise/Simulink的FCHEV燃料电池和动力蓄电池功率匹配研究

针对质子交换膜燃料电池和锂离子动力蓄电池混合动力电动汽车(FCHEV),利用AVL/Cruise和Matlab/Simulink软件搭建了FCHEV整车联合仿真平台。通过对车辆动力系统关键部件参数的分析,确定了若干可行的燃料电池和蓄电池功率匹配方案。基于一种目前比较成熟的控制策略,在NEDC循环工况下对各种匹配方案进行了仿真实验,在满足车辆动力性要求的前提下,对各方案的燃料经济性进行分析,从而得到该控制策略下燃料电池和动力蓄电池的最优功率匹配结果。     

Exploration and progress of high-energy supercapacitors and related electrode materials

As one of new electrical energy storage systems, supercapacitors possess higher energy density than conventional capacitors and larger power density than batteries, integrating substantial merits with high energy, large power delivery, long cycle life, obvious safety, and low cost. However, the unsatisfying energy density is the inhabiting issue for the wide commercial applications. As the energy density(E, W h kg?1) is directly proportional to specific capacitance(C, F g?1) and the square of operating voltage(V, V), in this review, we summarize the recent progress in two sections: the exploration of high-performance electrode materials to achieve high specific capacitance and the construction of high-voltage supercapacitor systems for high working voltage. The progressive explorations and developments in supercapacitors could guide the future research towards high-performance, low-cost, and safe energy storage devices.     

基于动力性与经济性的两挡纯电动汽车传动比优化

为实现纯电动汽车动力系统高效匹配,充分发挥关键部件的最大效用,以实现整车动力性与经济性最佳为目标进行研究,通过对纯电动汽车行业标准和整车参数的收集整理,确定XH2型纯电动汽车基本性能参数,根据前期已做的整车匹配选型工作,确定以动力系统传动比为优化变量的优化方案,利用matlab软件建立动力系统多目标优化数学模型,设定目标函数,引入4种非线性求解方式对模型求解。对比分析结果,得到该车的最佳传动比方案,该方案使整车动力性改善明显,经济性略有提高。     

Performance of a 60 F carbon nanotubes-based supercapacitor for hybrid power sources

A supercapacitor based on charge storage at the interface between a high surface area carbon nanotube electrode and a Li-ClO4/PC electrolyte was assembled. The performance of the capacitor depends on not only the material used in the cell but also the construction of the cell. From a constant charge-discharge test, the capacitance of 60 F was obtained. The performance of the power capacitor for pulse power sources was described. The specific energy (0.8 W·h·kg-1) and the specific power (0.75 kW·kg-1) of the power supercapacitor were demonstrated with a cell of the maximum operating voltage of 2.5 V. A hybrid power source consisting of a lithium ionic battery and the 60 F supercapacitor was demonstrated to power successfully a simulated power load encountered in GSM portable communication equipment. The addition of the supercapacitor to the power train of a cellular phone results in significantly more energy from the battery being used by the load. The experiments indicate that more than 33.8% energy i     

AMT混合动力系统驱动模式能量优化控制

在AMT混合动力系统转矩优化分配算法的基础上,提出了以动力总成系统效率最大化为目标的AMT档位优化控制来优化转速,并通过离线优化求解确定了不同状态(发动机和电机功率、车速、蓄电池SOC)下AMT的最优化档位控制规律和电机最优化转矩。仿真试验结果表明,能量优化控制算法显著改善了整车燃油经济性。     

基于Advisor的仿真软件的二次开发及其在复合电源混合动力汽车上的应用

对Advisor仿真平台进行了二次开发,获得了界面友好且适合复合电源混合动力汽车建模与仿真的专有技术平台,克服了用Advisor软件不能对由蓄电池和超级电容组成的复合电源混合动力汽车进行性能仿真的缺点。对复合电源混合动力汽车进行了性能仿真,并与原车单一蓄电池系统或超级电容系统进行了对比。仿真与对比结果表明:复合电源混合动力汽车的燃油经济性和动力性都得到了提高。     

Electromechanical coupling driving control for single-shaft parallel hybrid powertrain

The single-shaft parallel hybrid powertrain with the automatic mechanical transmission(AMT)is an efficient hybrid driving system in the hybrid electric bus(HEB),while the electromechanical coupling driving control becomes a complicated question to find a transient optimal control method to distribute the power between the engine and the electric machine(EM).This paper proposes an innovative control method to deal with the complicated transient coupling driving process of the electromechanical coupling driving system,considering the accelerating condition and the cruising condition mostly in the city driving cycle of HEB.The EM might be operated at driving mode or generating mode to assist the diesel engine to work in its high-efficiency area.Therefore,the adaptive torque tracking controller has been brought forward to ensure that the EM implements the demand torque as well as compensate the torque fluctuation of diesel engine.The d?q axis mathematical model and back stepping method are employed to deduce the adaptive controller and its adaptive laws.Simulation results demonstrate that the proposed control scheme can make the output torque of two power sources respond rapidly to the demand torque from the powertrain in the given driving condition.The proposed method could be adopted in the real control of HEB to improve the efficiency of the hybrid driving system.     

混合动力汽车发动机起停控制策略

应用PSAT前向仿真软件,对自主开发的双离合器并联混合动力车建立了整车仿真模型。并利用该模型对其发动机起停控制策略进行了仿真优化研究。结果表明:对于该混合动力车型,当发动机起动控制功率为10 kW/1200 r.min-1、停止控制功率为4 kW/800 r.min-1时,整车经济性能最佳,且在该起停功率下发动机、电机工作协调,动力总成工作模式切换平顺;将优化仿真结果应用到实车,验证了该控制策略的实用性。     

金属硫化物及其复合材料在超级电容器领域的研究进展

随着人们对于清洁能源要求的不断提高，超级电容器以具有超高比电容、高功率密度和长循环等特点引起人们的研究兴趣。超级电容器已经被应用在许多工业领域中。电极材料是决定超级电容器性能的重要因素之一。过渡金属硫化物因其具有独特的电子结构和多型性的特征被广泛用作为电极材料，但其在电化学循环过程中，容易产生穿梭效应和体积变化破坏电极材料的结构，导致倍率性能差、稳定性降低。本文综述金属硫化物的概况及其与石墨烯、碳纳米管、导电聚合物构建复合材料的最新发展，利用水热法、湿化学法，或者电化学法制备金属硫化物与不同组分的复合材料，可改善金属硫化物的电导率与倍率性能。在后续研究中，需要探索更简便、成本较低的方法制备具有分级纳米结构的高性能金属硫化物复合材料。     

混合动力电动客车驱动系统控制策略及仿真

提出了一种混联式混合动力城市公交客车驱动系统的机电偶合方案及工作模式。针对某一运行工况，以维持电池SOC平衡为主要目标，设计了该驱动系统的控制策略；基于ADVISOR2002，建立了该驱动系统的仿真模型。仿真结果表明，控制策略和仿真模型能满足混合动力城市公交客车驱动系统的设计要求。     

混合动力汽车车载复合电源参数匹配及其优化

在分析超级电容的加载对混合动力汽车各动力部件参数影响的基础上,提出了复合电源合理的布局形式。针对整车对电源功率、能量的要求对复合系统进行参数匹配,以电源全寿命使用成本最少为目标进行参数优化。对所匹配的结果进行了仿真分析,结果表明,复合电源应用于混合动力汽车,在质量、体积、全寿命使用成本及制动能量回收效能等方面均优于原单一电池。     

NiAl-LDHs 电极材料的水热合成及其超级电容器电化学性能

超级电容器具有大充放电速率、良好的循环稳定性及高功率密度等优点, 是一种新兴的绿色环保储能器件。采用简单的水热合成法制备镍铝层状双金属氢氧化物(NiAl-LDHs) 超级电容器电极材料, 探究不同镍铝比对其形貌组成及电化学性能的影响。所制备的Ni₁Al₁-LDHs 电极材料在电流密度为1 A/g 时表现出378 F/g 的高比电容。以活性炭(AC) 为负极组成的Ni₁Al₁-LDHs//AC 非对称超级电容器在能量密度为27.5 Wh/kg 时, 具有1.4 kW/kg 的高功率密度, 表现出优异的电化学性能。     

Large-scale multirole Zn(Ⅱ) programmed synthesis of ultrathin hierarchically porous carbon nanosheets

ZIF-derived carbon structures are considered as desired electrode materials for supercapacitors due to their high surface area,high conductivity, and porous structure. However, the most reported ratio of 2-methylimidazole and Zn(II) is 4:1 to 20:1, which limits commercial applications due to the increasing cost. In this paper, a multirole Zn(II)-assisted method is presented from Zn(II) solution, Zn O, Zn O/ZIF-8 core-shell nanostructure, to 3 D hierarchical micro-meso-macroporous carbon structures with a1:1 ratio of 2-methylimidazole and Zn(II). The hierarchically porous carbon has a high surface area of 1800 m2 g~(-1) due to the synergistic effect of multirole Zn(II). The unique carbon-based half-cell delivers the specific capacitances of 377 and 221 F g~(-1) at the current densities of 1.0 and 50 A g~(-1), respectively. As a 2.5 V symmetrical supercapacitor, the device reveals a high doublelayer capacitance of 24.4 F g~(-1), a power density of 62.5 k W kg~(-1), and more than 85.8% capacitance can be retained over 10000 cycles at 10 A g~(-1). More importantly, the low-cost hierarchically porous carbon could be easily produced on a large scale and almost all chemicals can be reused in the sustainable method.     

Structure improvement and electrochemical studies of bipolar nickel metal hydride batteries for hybrid electric vehicles

Inrecentyears,globalenvironmentalpollutionproblemssuchasacidrain,greenhouseeffectandairpollutionbecomemoreandmoreserious,especiallyinbigcities[1].Thedevelopmentandcommercializationofelectricvehiclesandhybridelectricvehiclesisakeyfactorintheresolutionofthesematters[2].However,thefinalacceptanceofthesezero emissionvehiclesdependsstronglyontheperformanceofbatteries.Ni/MHispres entlythemostpromisingbatterysystemforhybridvehi clespropulsionintheshortandmid term,whichhasmanyadvantagessuchashighener…     

Rare earth and transitional metal colloidal supercapacitors

The search of electrode materials with high electrochemical activity is one of key solutions to actualize both high energy density and high power density in a supercapacitor. Recently, we have developed one novel kind of rare earth and transitional metal colloidal supercapacitors, which can deliver higher specific capacitance than electrical double-layer capacitors(EDLC) and traditional pseudocapacitors. The electrode materials in colloidal supercapacitors are in-situ formed electroactive colloids, which were transformed from commercial rare earth and transitional metal salts in alkaline electrolyte by chemical and electrochemical assisted coprecipitation. In these colloidal supercapacitors, multiple-electron Faradaic redox reactions can be utilized, which can deliver ultrahigh specific capacitance often larger than one-electron capacitance. Multiple-valence metal cations used in our designed colloidal supercapacitors mainly include Ce3+, Yb3+, Er3+, Fe3+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Sn2+ and Sn4+. The colloidal supercapacitors can be served as the promising next-generation high performance supercapacitors.     

基于2.5 Gbit/s应用长波长雪崩光电二极管

设计并制作一种基于2．5Gbit／s应用的分离吸收区和倍增区结构的InGaAs／InP雪崩光电二极管(avalanche photodiode,APD),该APD具有低击穿电压VBR(典型值为40 V)和低暗电流(反偏电压为0．9 VBR时典型值为1 nA)的显著特点,适合低工作电压的应用场合,如小型化的SFP和SFF光通信模块．组件测试结果表明,该APD具有高的饱和光功率和灵敏度,适用于2．5Gbit／s及以下光通信及测量系统中对1310 nm／1550 nm波长光的探测．