基于综合燃油消耗率的混合动力汽车能量管理策略研究

通过对单轴并联式混合动力汽车综合燃油消耗率的建模计算,以综合燃油消耗率(Integrated Specific Fuel Consumption,ISFC)最低为目标确定了该混合动力系统各工作模式的工作范围,并制定了相应的整车能量管理策略。在此基础上,利用Matlab/Simulink仿真平台,建立了混合动力系统能量管理策略的仿真模型,结果表明采用控制策略使该混合动力汽车的燃油经济性比传统汽车和采用基线控制策略的相同混合动力汽车有显著提高。     

串联混合动力摩托车动力系统设计及仿真

根据我国两轮机动车市场的未来发展需求和城市行驶工况特点,在对比分析了两种混合动力系统结构之后,选择了串联式驱动形式作为摩托车混合动力系统结构,介绍了串联式混合动力摩托车动力系统主要动力部件的选型和参数匹配,并对串联式混合动力摩托车和传统驱动结构摩托车在燃油经济性和排放上进行了基于AVL_CRUISE软件的仿真对比.     

油电混合动力无人机能量管理策略的对比仿真研究

针对固定飞行任务的油电混合动力无人机,降低混合动力系统瞬时燃油消耗率,增加续航里程的工作需求,设计了可以应用于固定飞行任务油电混合动力无人机的不同能量管理策略,主要包括固定规则、模糊逻辑和动态规划算法的能量管理策略。根据油电混合动力无人机动力源特性,通过理论和试验建模相结合的方法,在MATLAB中建立油电混合动力系统的数学模型、飞行任务相对应的仿真工况及不同能量管理策略的控制程序。重点对比了基于优化的动态规划算法能量管理策略相比固定规则和模糊逻辑策略在燃油经济性和运行稳定性方面的表现。仿真结果表明：动态规划算法策略的累积燃油消耗量相比固定规则、模糊逻辑策略分别下降了4.6%和6.5%,平均瞬时燃油消耗率分别下降了5.1%和5.9%;在应对外部突风扰动时,动态规划能量管理策略的航空发动机最大转速波动相比固定规则的能量管理策略下降了59.7%,应对随机紊流扰动时,动态规划策略航空发动机的最大转速波动相比固定规则和模糊逻辑分别下降了33.9%、25.6%。动态算法作为一种全局最优算法,应用在固定飞行任务的油电混合动力无人机能量管理策略中时,可在提高混合动力系统燃油经济性的同时保证系统运行的稳定性。     

混合动力电动汽车实时控制策略

合理有效的能量管理策略是混合动力电动汽车(HEV)取得最佳燃油经济性、降低排放和保持良好动力性的关键。本文对混合动力电动汽车能量管理策略的分类、现状和发展趋势进行了介绍，并详细分析了基于全局优化理论的实时能量管理策略原理。实时控制策略模型将电机输出功率转化为等效的燃油消耗量，以车辆的动力性为限制条件，以燃油经济性和排放最小化为目标建立目标函数模型，为发动机和电动机工作点的决策提供合理的目标函数。实时控制根据行驶路况实时调整发动机和电动机的工作方式，实现了实时全局优化。     

复合翼无人机混合动力系统能量管理策略设计

以某最大起飞质量为25 kg的复合翼无人机混合动力系统为研究对象,基于MATLAB/Simulink平台搭建动力系统关键部件数学模型、集成复合翼无人机混合动力系统级仿真模型,依据复合翼无人机在多点悬停作业场景下的飞行任务要求,设计相应的飞行任务剖面与基于等效燃油最小消耗的能量管理策略,进行仿真试验验证。结果表明：基于等效燃油最小消耗能量管理策略的无人机动力系统的油门跟随性良好,满足无人机实际运行需要;动力电池荷电状态可以维持在设定值附近,相对误差小于1.5%;相比基于规则的能量管理策略,基于等效燃油最小消耗管理策略的混合动力系统无人机在点对点飞行和多点悬停作业2种飞行工况下的燃油消耗分别下降了6.07%、5.49%。     

基于锂电池温度特性的混合动力系统能量管理策略研究

为了提高重型串联式混合动力车辆的工作可靠性,从混合动力系统的组成架构入手,分析了系统的动力单元的特性和储能电池组的特性。而后基于Thevenin模型研究了电池组荷电状态和温度对电池的欧姆内阻和极化内阻的影响,由于电池温度对电池内阻有着显著地影响,提出了考虑电池温度特性的混合动力系统能量管理策略,即根据电池温度实时控制电池组的充电、放电电流,避免电池在极端温度下大倍率充放电引起的母线电压波动及电芯损坏等危害。实车道路测试对比了现有控制策略和所提出的控制策略,证明了基于电池温度的充放电功率控制策略的有效性。     

基于价值损耗的燃料电池混合动力能量管理策略评价

为了评价燃料电池混合动力系统能量管理策略的经济性,对基于状态机和模糊逻辑2种能量管理策略的燃料电池混合动力叉车的价值损耗进行分析。首先,通过分析燃料电池和锂电池的工作特性,分别构建依赖实际工况的燃料电池单体电压衰减率模型和锂电池容量衰减率模型;同时定义计及燃料电池氢耗量的燃料电池混合动力系统的综合价值损耗指标。其次,通过测试叉车极限工况,计算燃料电池功率和锂电池容量,并根据母线电压确定锂电池SOC范围。最后,设计基于状态机和模糊逻辑的2种燃料电池混合动力叉车能量管理策略,并通过仿真分析在叉车一次循环工况下2种能量管理的价值损耗。研究结果表明:相较于模糊逻辑策略,采用状态机策略造成燃料电池寿命损耗提高7.81%,氢耗量提高1.89倍,锂电池寿命损耗减小21.33%。     

基于Cruise和Simulink软件对可充电式串联混动汽车经济性仿真

基于AVL Cruise和Simulink建立了联合仿真平台,引入了基于规则的功率跟随能量管理控制策略,结合蓄电池组SOC的变化情况,对Plug-in串联式混合动力进行了初步仿真,分析了采用串联式混动能量管理控制策略对整车经济性和排放性的影响。     

燃料电池混合动力机车参数匹配与等效氢耗优化能量管理方法

为提升燃料电池机车混合动力系统综合经济性，基于机车动力性能分析提出一种基于配置成本优化的燃料电池混合动力系统参数匹配方法。在此基础上，将锂电池能耗等效为燃料电池的氢气消耗，并提出一种基于等效氢耗实时优化的燃料电池混合动力系统能量管理方法，以降低系统整体能耗水平。基于某机车实际参数对所提方法进行可行性验证。结果表明，机车配置10套150 kW的燃料电池和549串16并的锂电池，可在机车安全稳定运行的基础上，实现系统总购置成本最优，并且，基于所提出的能量管理方法，系统等效氢气消耗降低8.44%，混合动力系统的综合经济性得到明显改善。     

同步碎石封层车增程电驱动混合动力系统设计研究

通过分析传统同步碎石封层车的整车结构、工作原理、作业流程,提出了同步碎石封层车串联混合动力系统结构;基于某型号同步碎石封层车基本参数及动力性能指标,对同步碎石封层车混合动力系统中主要动力元件进行参数匹配研究及选型;结合混动同步碎石封层车4种工作模式下能量流动特点和转场、作业两种工况下的能量需求,研究系统能源管理系统,制定增程式车辆发动机和辅助能量源间的能源管理策略。运用Cruise仿真软件搭建同步碎石封层车混合动力系统仿真模型,将所提能源管理策略导入Cruise仿真平台,基于Cruise和MATLAB联合仿真来研究混动同步碎石封层车动力性能。仿真结果表明：混合动力同步碎石封层车各部分参数匹配都能很好地满足工作要求,发动机可以一直工作在最佳范围内,波动较小,混动同步碎石封层车节油率为24.7%,能量回收率为20.34%,燃油经济性能得到较大提高。     

Brazilian hybrid electric-hydrogen fuel cell bus: Improved on-board energy management system

The present paper unveils the technology developed for a series hybrid battery-dominant electric-hydrogen fuel cell plug-in city bus. It possesses a homemade power train with three electric energy sources, which are the grid-charged energy, the one produced by the fuel cell that works at constant power and acts as a range extender and that resultant from the regeneration of kinetic energy. Emphasis was given to the design of the hybridization energy engineering that has predominance of power in batteries and predominance of energy with hydrogen. The remarkable amount of 46.6% of the total energy input reaches the motor axle for effective motion and a fuel economy of 6.7 kg H₂/100 km was achieved. A total owner cost analysis has shown that computation of capital, operational and fueling costs makes the present bus 133% more expensive than a conventional diesel powered one. Commercialization prospects, and also social and environmental impacts are analyzed.     

Energy management strategy based on fuzzy logic for a fuel cell hybrid bus

Fuel cell vehicles, as a substitute for internal-combustion-engine vehicles, have become a research hotspot for most automobile manufacturers all over the world. Fuel cell systems have disadvantages, such as high cost, slow response and no regenerative energy recovery during braking; hybridization can be a solution to these drawbacks. This paper presents a fuel cell hybrid bus which is equipped with a fuel cell system and two energy storage devices, i.e., a battery and an ultracapacitor. An energy management strategy based on fuzzy logic, which is employed to control the power flow of the vehicular power train, is described. This strategy is capable of determining the desired output power of the fuel cell system, battery and ultracapacitor according to the propulsion power and recuperated braking power. Some tests to verify the strategy were developed, and the results of the tests show the effectiveness of the proposed energy management strategy and the good performance of the fuel cell hybrid bus.     

Adaptive supervisory control strategy of a fuel cell/battery-powered city bus

This paper presents an adaptive supervisory control strategy for a fuel cell/battery-powered city bus to fulfill the complex road conditions in Beijing bus routes. An equivalent consumption minimization strategy (ECMS) is firstly proposed to optimize the fuel economy. The adaptive supervisory control strategy is exploited based on this, incorporating an estimating algorithm for the vehicle accessorial power, an algorithm for the battery charge-sustaining and a Recursive Least Squares (RLS) algorithm for fuel cell performance identification. Finally, an adaptive supervisory controller (ASC) considering the fuel consumption minimization, the battery charge-sustaining and the fuel cell durability has been implemented within the hybrid city buses. Results in the “China city bus typical cycle” testing and the demonstrational program of Beijing bus routes are presented, demonstrating that this approach provides an improvement of fuel economy along with robustness and ease of implementation. However, the fuel cell system does not leave much room for the optimal strategy to promote the fuel economy. Benefits may also result in a prolongation of the fuel cell working life, which needs to be verified in future.     

Numerical simulation model for the preliminary design of hybrid electric city bus power train with polymer electrolyte fuel cell

A hybrid power train, consisting of a Polymer Electrolyte Fuel Cell (PEFC) system and batteries, which feeds an electric motor for city bus propulsion, can be dimensioned ad hoc respect to the performed route, avoiding his oversizing in the greater energy rationalization optic.     

A fuel cell city bus with three drivetrain configurations

Three fuel cell city buses of the energy hybrid- and power hybrid-type were re-engineered with three types of drivetrain configuration to optimize the structure and improve the performance. The energy distribution, hydrogen consumption, state of charge (SOC) and the power variation rate were analyzed when different drivetrain configurations and parameters were used. When powered only by a fuel cell, the bus cannot recover the energy through regenerative braking. The variation of the fuel cell power is large and frequent, which is not good for the fuel cell. When the fuel cell is linked to a battery pack in parallel, the bus can recover the energy through regenerative braking. The energy distribution is determined by the parameters of the fuel cell and the battery pack in the design stage to reduce the power variation rate of the fuel cell. When the fuel cell and DC/DC converter connected in series links the battery pack in parallel, energy can be recovered and the energy distribution can be adjusted online. The power variation rate of both the fuel cell and the battery pack are reduced.     

Fuel processor-battery-fuel cell hybrid drivetrain for extended range operation of passenger vehicles

Power required to run auxiliary systems on a passenger car, such as those for air conditioning and advanced vehicle control, reduces the driving range of a vehicle equipped with a hybrid drive train. Under practical driving conditions, a significant amount of additional energy is required at low power levels compared to the rated power of the drive unit. In the present study, we consider a fuel cell-battery drive train augmented by an on-board fuel (ethanol) processor to provide the motoring power requirements of a car. Using systematic driving cycle simulations that take account of power-to-weight, energy-to-weight and power-to-efficiency factors of on-board power sources under simulated load conditions, we show that a combination of steadily-operated compact ethanol reformer, a low-power battery continuously charged by excess reformer capacity and a high-power fuel cell powered by conservatively-used hydrogen from cylinder can increase the range of hybrid fuel cell drivetrains to about 750 km. Although the overall energy consumption of the three-way hybrid is more than that of fuel cell-battery hybrid, lesser use of stored hydrogen improves the fuel economy of the hybrid drivetrain. While the system complexity is increased, long-range distressed mode operation becomes feasible with the added fuel processor.     

Design of a hybrid electric fuel cell power train for an urban bus

With the requirements for reducing emissions and improving fuel economy, new markets have become attractive for automotive companies that are developing electric, hybrid, and plug-in vehicles using new technologies candidates to be implemented in the next generations of vehicles. Most of all, hybrid vehicles are attracting interest due to great potential to achieve higher fuel economy and a longer range with respect to pure electric mode but often this solution is not petroleum free. Within a national project CNR TAE Institute is involved in the development of a zero emission hybrid electric city bus based on PEM fuel cell technology able to increase the range at least 30% with respect to the same vehicle in pure electric configuration. Design, control and preliminary results are reported in this paper.     

Optimal vehicle control strategy of a fuel cell/battery hybrid city bus

In this article, an optimal vehicle control strategy based on a time-triggered controller area network (TTCAN) system for a polymer electrolyte membrane (PEM) fuel cell/nickel-metal hydride (Ni-MH) battery powered city bus is presented. Aiming at improving the fuel economy of the city bus, the control strategy comprises an equivalent consumption minimization strategy (ECMS) and a braking energy regeneration strategy (BERS). On the basis of the introduction of a battery equivalent hydrogen consumption model incorporating a charge-sustaining coefficient, an analytical solution to the equivalent consumption minimization problem is given. The proposed strategy has been applied in several city buses for the Beijing Olympic Games of 2008. Results of the “China city bus typical cycle” testing show that, the ECMS and the BERS lowered hydrogen consumption by 2.5% and 15.3% respectively, compared with a rule-based strategy. The BERS contributes much more than the ECMS to the fuel economy, because the fuel cell system does not leave much room for the optimal algorithm in improving the efficiency.     

Proton exchange membrane fuel cell system diagnosis based on the multivariate statistical method

Although electric-powered vehicles have developed rapidly in recent years, with significant progress in the lithium power battery industry, the Fuel Cell Electric Vehicle (FCEV) is still a competitive choice for a clean transportation solution, because of its extended driving range, zero emissions, and fast fuel recharging capability. In particular the fuel cell hybrid bus used for city traffic is the FCEV type most likely to be commercialized. Demonstration programs for a fuel cell bus fleet have been operated for a few years in China. It is necessary to develop comprehensive diagnostic tools to increase the reliability of these systems, because fuel cell city buses serve large numbers of passengers using public transportation. This paper presents a diagnostic analysis and implementation study based on the Principal Component Analysis (PCA) method for the fuel cell system. This diagnostic system was successfully implemented for detecting a fuel cell stack sensor network failure in the fuel cell bus fleet at the Shanghai Expo in 2010.