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。     

车用柴油串联式混合动力系统经济性试验研究

为评估柴油串联式混合动力客车动力系统的性能,特别是燃油经济性,建立了串联式混合动力系统测试平台.在详细描述串联式混合动力系统能量管理策略和辅助动力单元(APU)控制的基础上,通过中国城区公交道路循环测试,对影响串联式混合动力系统燃油经济性的几个要素进行了分析.研究结果表明:在既定能量管理策略的基础上,制动能量回馈、电驱动子附件功率和发动机怠速是影响燃油经济性的三个显著因素.     

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%。     

并联式混合动力汽车的基本控制策略和实时控制策略的比较分析

基于上海市道路行驶工况,采用对混合动力汽车性能仿真的方法,对混合动力汽车的基本控制策略和实时控制策略进行了比较分析。结果表明：基本控制策略主要针对混合动力系统的经济性能,是一种对发动机良好工作区域控制的方法,具有简单易行的特点;实时控制策略主要针对混合动力系统的经济性能和排放性能特别是NOx放性能,对发动机工作点进行了实时优化控制,更为全面和精确。     

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%。     

浅析混合动力汽车总成结构与能量控制策略

通过浅析插电式混合动力汽车（PHEV）动力总成结构与能量控制策略,阐述了新能源汽车对提高燃油经济性,促进节能减排的深刻意义。     

一种混合内燃机动力系统控制研究

介绍了以内燃机工作特性为基础的某混合动力系统的控制算法.利用CRIUSE建立了该混合动力系统和整车动力学模型,控制策略模型則在Matlab/Simulink环境下实现.通过仿真计算,在满足动力性的前提下,该系统和控制算法对车辆的燃油经济性提高显著,在电能自平衡工况下,城市循环工况油耗为7.3 L/100 km,节油循达33%;外部充电时,综合节油率可达50%.     

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。     

并联混合动力汽车能量管理与转矩协调控制策略

研究并联混合动力汽车的控制策略。基于发动机输出转矩最优的能量管理策略,对并联混合动力汽车在工作模式切换中的相互配合问题,提出发动机动态转矩控制+动力电池荷电状态(state of charge,SOC)干预+电机转矩补偿控制的转矩协调控制方法;在Matlab/Simulink/Stateflow平台搭建整车能量管理控制策略模型,控制发动机工作在高效率区,保证发动机输出最优转矩;根据电池的SOC干预电机的运行状态,协同发动机提供整车需求转矩。在Cruise平台下建立整车模型,以新欧洲驾驶周期作为循环工况进行离线仿真。结果表明,能量管理与转矩协调控制策略能够有效分配电机和发动机的转矩输出,满足混合动力汽车多模式切换的要求。     

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。     

Economic energy management strategy design and simulation for a dual-stack fuel cell electric vehicle

This paper presents the design and simulation validation of two energy management strategies for dual-stack fuel cell electric vehicles. With growing concerns about environmental issues and the fossil energy crisis, finding alternative methods for vehicle propulsion is necessary. Proton exchange membrane (PEM) fuel cell systems are now considered to be one of the most promising alternative energy sources. In this work, the challenge of further improving the fuel economy and extending the driving range of a fuel cell vehicle is addressed by a dual-stack fuel cell system with specific energy management strategies. An efficiency optimization strategy and an instantaneous optimization strategy are proposed. Simulation validation for each strategy is conducted based on a dual-stack fuel cell electric vehicle model which follows the new European driving cycle (NEDC). Simulation results show that a dual-stack fuel cell system with proposed energy management strategies can significantly improve the fuel economy of a fuel cell vehicle and thus lengthen the driving range while being able to keep the start-stop frequency of the fuel cell stack within a reasonable range.     

A wavelet-fuzzy logic based energy management strategy for a fuel cell/battery/ultra-capacitor hybrid vehicular power system

Due to increasing concerns on environmental pollution and depleting fossil fuels, fuel cell (FC) vehicle technology has received considerable attention as an alternative to the conventional vehicular systems. However, a FC system combined with an energy storage system (ESS) can display a preferable performance for vehicle propulsion. As the additional ESS can fulfill the transient power demand fluctuations, the fuel cell can be downsized to fit the average power demand without facing peak loads. Besides, braking energy can be recovered by the ESS. This study focuses on a vehicular system powered by a fuel cell and equipped with two secondary energy storage devices: battery and ultra-capacitor (UC). However, an advanced energy management strategy is quite necessary to split the power demand of a vehicle in a suitable way for the on-board power sources in order to maximize the performance while promoting the fuel economy and endurance of hybrid system components. In this study, a wavelet and fuzzy logic based energy management strategy is proposed for the developed hybrid vehicular system. Wavelet transform has great capability for analyzing signals consisting of instantaneous changes like a hybrid electric vehicle (HEV) power demand. Besides, fuzzy logic has a quite suitable structure for the control of hybrid systems. The mathematical and electrical models of the hybrid vehicular system are developed in detail and simulated using MATLAB^®, Simulink^® and SimPowerSystems^® environments.     

Analytical method to evaluate fuel consumption of hybrid electric vehicles at balanced energy content of the electric storage devices

Innovative analytically based method to calculate corrected fuel consumption of parallel and series hybrid electric vehicles (HEVs) at balanced energy content of the electric storage devices is proposed and validated in the paper. The proposed analytical method is generally applicable and features highly accurate corrected fuel consumption results. It enables calculation of the corrected fuel consumption out of a single fuel consumption test run in a single analytic post-processing step. An additional fuel consumption test run might be needed to obtain highly accurate results if ratio of the energy content deviation of the electric storage devices to the energy used for vehicle propulsion over the test cycle is high. Proposed method enables consideration of non-linear energy flow changes and non-linear HEV component efficiency changes caused by the energy management strategy or by the component characteristics. The method therefore features highly accurate results out of the minimum number of fuel consumption test runs and thus optimizes workload for development or optimization of HEVs. The input data of the method are characteristic energy flows and efficiencies that are derived from the energy flows on selected energy paths of HEVs.     

A hierarchical energy management strategy for fuel cell/battery/supercapacitor hybrid electric vehicles

In this paper, a hierarchical energy management strategy (EMS) based on low-pass filter and equivalent consumption minimization strategy (ECMS) is proposed in order to lift energy sources lifespan, power performance and fuel economy for hybrid electrical vehicles equipped with fuel cell, battery and supercapacitor. As for the considered powertrain configuration, fuel cell serves as main energy source, and battery and supercapacitor are regarded as energy support and storage system. Supercapacitor with high power density and dynamic response acts during great power fluctuations, which relives stress on fuel cell and battery. Meanwhile, battery is used to lift the economy of hydrogen fuel. In higher layer strategy of the proposed EMS, supercapacitor is employed to supply peak power and recycle braking energy by using the adaptive low-pass filter method. Meantime, an ECMS is designed to allocate power of fuel cell and battery such that fuel cell can work in a high efficient range to minimize hydrogen consumption in lower layer. The proposed EMS for hybrid electrical vehicles is modeled and verified by advisor-simulink and experiment bench. Simulation and experiment results are given to confirm effectiveness of the proposed EMS of this paper.     

A comparison of high-speed flywheels, batteries, and ultracapacitors on the bases of cost and fuel economy as the energy storage system in a fuel cell based hybrid electric vehicle

Fuel cells aboard hybrid electric vehicles (HEVs) are often hybridized with an energy storage system (ESS). Batteries and ultracapacitors are the most common technologies used in ESSs aboard HEVs. High-speed flywheels are an emerging technology with traits that have the potential to make them competitive with more established battery and ultracapacitor technologies in certain vehicular applications. This study compares high-speed flywheels, ultracapacitors, and batteries functioning as the ESS in a fuel cell based HEV on the bases of cost and fuel economy. In this study, computer models were built to simulate the powertrain of a fuel cell based HEV where high-speed flywheels, batteries, and ultracapacitors of a range of sizes were used as the ESS. A simulated vehicle with a powertrain using each of these technologies was run over two different drive cycles in order to see how the different ESSs performed under different driving patterns. The results showed that when cost and fuel economy were both considered, high-speed flywheels were competitive with batteries and ultracapacitors.     

Fuel economy evaluation of fuel cell hybrid vehicles based on equivalent fuel consumption

Fuel cell hybrid vehicles (FCHVs) have become a major topic of interest in the automotive industry owing to recent energy supply and environmental problems. Consequently, fuel economy evaluation methods of FCHVs have a popular research topic. The initial state of charge (SOC) and the final SOC of the battery have to be identical in an evaluation of the fuel economy of an FCHV. In an actual driving situation or during a forward simulation, however, the final SOC depends on the power management strategy, which is usually different from the initial SOC. To consider the effect of the difference between the initial and final SOC on fuel economy evaluation, the concept of equivalent fuel consumption, based on the optimal control, is introduced in this paper. A rule-based power management strategy is applied to an FCHV, and its fuel economy is evaluated in terms of the equivalent fuel consumption and compared to the optimal control result.     

Energy for sustainable road transportation in China: Challenges,initiatives and policy implications

This paper presents an overview of the initiatives launched in energy supply and consumption and the challenges encountered in sustainable road transportation development in China. It analyzes the main energy challenges related to road transportation development arising in the context of economic development, rapid urbanization, and improvement in living standards. It also discusses technological- and policy initiatives needed to deal with these challenges, drawing comparisons with foreign experience: promoting the development and dissemination of alternative fuels and clean vehicles such as: LPG, CNG, EV, HEV, FCV, ethanol, methanol, DME, bio-diesel, and CTL, strengthening regulations relating to vehicle fuel economy and emission, improving traffic efficiency and facilitating public transport development, and strengthening management of the soaring motor vehicle population. If the current pattern continues, by the year 2030, the vehicle population in China will be 400 million and fuel demand will be 350 million tons. The potential energy saving capacity being 60%, the actual oil demand by 2030 from on-road vehicles might technically be kept at the current level by improving fuel economy, propagating use of HEV and diesel vehicles, improving supply of alternative fuels, and developing public transport. Several uncertainties are identified that could greatly influence the effect of the technical proposals: traffic efficiency, central government's resolve, and consumers' choice.     

基于微遗传算法的船用柴油机喷油策略优化及研究

为优化大型船用柴油机的燃油喷射策略,采用微种群遗传算法结合三维数值模拟,在一台大缸径低速船用柴油机上对两个喷油器的主喷时刻、预喷间隔和预喷比例进行了优化,并在优化算例的基础上研究了大型船用柴油机各个喷油器预喷参数和顺序喷射对性能与排放的影响。研究结果表明,在采用顺序喷射的前提下,顺序喷射间隔影响NOx排放和指示燃油消耗率。第一个和第二个喷油器的预喷策略对大型船用柴油机的性能与排放有不同的影响,前者是预喷放热与主喷滞燃期缩短综合作用的结果,而后者主要是预喷放热自身的影响。通过以上研究和优化,柴油机的NOx排放降低了21.27%,表明该方法可以用于优化大型船用柴油机的喷射策略。     

Comparison among various energy management strategies for reducing hydrogen consumption in a hybrid fuel cell/supercapacitor/battery system

The aim of this study is to introduce a comprehensive comparison of various energy management strategies of fuel cell/supercapacitor/battery storage systems. These strategies are utilized to manage the energy demand response of hybrid systems, in an optimal way, under highly fluctuating load condition. Two novel strategies based on salp swarm algorithm (SSA) and mine-blast optimization are proposed. The outcomes of these strategies are compared with commonly used strategies like fuzzy logic control, classical proportional integral control, the state machine, equivalent fuel consumption minimization, maximization, external energy maximization, and equivalent consumption minimization. Hydrogen fuel economy and overall efficiency are used for the comparison of these different strategies. Results demonstrate that the proposed SSA management strategy performed best compared with all other used strategies in terms of hydrogen fuel economy and overall efficiency. The minimum consumed hydrogen and maximum efficiency are found 19.4 gm and 85.61%, respectively.