Implementation of Radial Basis Function Artificial Neural Network into an Adaptive Equivalent Consumption Minimization Strategy for Optimized Control of a Hybrid Electric Vehicle

Continued increases in the emission of greenhouse gases by passenger vehicles have accelerated the production of hybrid electric vehicles. With this increase in production, there has been a parallel demand for continuously improving strategies of hybrid electric vehicle control. The goal of an ideal control strategy is to maximize fuel economy while minimizing emissions. Methods exist by which the globally optimal control strategy may be found. However, these methods are not applicable in real-world driving applications since these methods require a priori knowledge of the upcoming drive cycle. Real-time control strategies use the global optimal as a benchmark against which performance can be evaluated. The goal of this work is to use a previously defined strategy that has been shown to closely approximate the global optimal and implement a radial basis function (RBF) artificial neural network (ANN) that dynamically adapts the strategy based on past driving conditions. The strategy used is the Equivalent Consumption Minimization Strategy (ECMS), which uses an equivalence factor to define the control strategy and the power train component torque split. An equivalence factor that is optimal for a single drive cycle can be found offline with a priori knowledge of the drive cycle. The RBF-ANN is used to dynamically update the equivalence factor by examining a past time window of driving characteristics. A total of 30 sets of training data (drive cycles) are used to train the RBF-ANN. For the majority of drive cycles examined, the RBF-ANN implementation is shown to produce fuel economy values that are within ±2.5% of the fuel economy obtained with the optimal equivalence factor. The advantage of the RBF-ANN is that it does not require a priori drive cycle knowledge and is able to be implemented in real-time while meeting or exceeding the performance of the optimal ECMS. Recommendations are made on how the RBF-ANN could be improved to produce better results across a greater array of driving conditions.

A Novel Method for the Application of the ECMS(Equivalent Consumption Minimization Strategy)to Reduce Hydrogen Consumption in Fuel Cell Hybrid Electric Vehicles

Fuel cell hybrid electric vehicles are currently being considered as ideal means to solve the energy crisis and global warming in today’s society.In this context,this paper proposes a method to solve the problem related to the dependence of the so-called optimal equivalent factor(determined in the framework of the equivalent consumption minimum strategy-ECMS)on the working conditions.The simulation results show that under typical conditions(some representative cities being considered),the proposed strategy can maintain the power balance;for different initial battery’s states of charge(SOC),after the SOC stabilizes,the fuel consumption is 5.25 L/100 km.

A Predictive Energy Management Strategies for Mining Dump Trucks

The plug-in hybrid vehicles(PHEV)technology can effectively address the issues of poor dynamics and higher energy consumption commonly found in traditional mining dump trucks.Meanwhile,plug-in hybrid electric trucks can achieve excellent fuel economy through efficient energy management strategies(EMS).Therefore,a series hybrid system is constructed based on a 100-ton mining dump truck in this paper.And inspired by the dynamic programming(DP)algorithm,a predictive equivalent consumption minimization strategy(P-ECMS)based on the DP optimization result is proposed.Based on the optimal control manifold and the SOC reference trajectory obtained by the DP algorithm,the P-ECMS strategy performs real-time stage parameter optimization to obtain the optimal equivalent factor(EF).Finally,applying the equivalent consumption minimization strategy(ECMS)realizes real-time control.The simulation results show that the equivalent fuel consumption of the P-ECMS strategy under the experimentally collected mining cycle conditions is 150.8 L/100 km,which is 10.9%less than that of the common CDCS strategy(169.3 L/100 km),and achieves 99.47%of the fuel saving effect of the DP strategy(150 L/100 km).

Research on ECMS Based on Segmented Path Braking Energy Recovery in a Fuel Cell Vehicle

Proton exchange membrane fuel cells are widely regarded as having the potential to replace internal combustion engines in vehicles.Since fuel cells cannot recover energy and have a slow dynamic response,they need to be used with different power sources.Developing efficient energy management strategies to achieve excellent fuel economy is the goal of research.This paper proposes an adaptive equivalent fuel minimum consumption strategy(AECMS)to solve the problem of the poor economy of the whole vehicle caused by the wrong selection of equivalent factors(EF)in traditional ECMS.In this method,the kinematics interval is used to update the equivalent factor by considering the penalty term of energy recovery on SOC changes.Finally,the optimized equivalent factor is substituted into the optimization objective function to achieve efficient energy regulation.Simulation results under the New European Driving Cycle show that compared with the traditional ECMS based on fixed SOC benchmarks,the proposed method improves fuel economy by 1.7%while ensuring vehicle power and increases SOC by 30%.

Variable Parameter Self-Adaptive Control Strategy Based on Driving Condition Identification for Plug-In Hybrid Electric Bus

A variable parameter self-adaptive control strategy based on driving condition identification is proposed to take full advantage of the fuel saving potential of the plug-in hybrid electric bus(PHEB).Firstly,the principal component analysis(PCA)and the fuzzy c-means clustering(FCM)algorithm is used to construct the comprehensive driving cycle,congestion driving cycle,urban driving cycle and suburban driving cycle of Chinese urban buses.Secondly,an improved particle swarm optimization(IPSO)algorithm is proposed,and is used to optimize the control parameters of PHEB under different driving cycles,respectively.Then,the variable parameter self-adaptive control strategy based on driving condition identification is given.Finally,for an actual running vehicle,the driving condition is identified by relevance vector machine(RVM),and the corresponding control parameters are selected to control the vehicle.The simulation results show that the fuel consumption of using the variable parameter self-adaptive control strategy is reduced by 4.2% compared with that of the fixed parameter control strategy,and the feasibility of the variable parameter self-adaptive control strategy is verified.

融合工况预测的燃料电池汽车里程自适应等效氢耗最小控制策略

为有效地提高插电式燃料电池汽车的经济性,实现燃料电池和动力电池的功率最优分配,考虑到行驶工况、电池荷电状态(State of charge,SOC)、等效因子与氢气消耗之间的密切联系,制定融合工况预测的里程自适应等效氢耗最小策略.通过基于误差反向传播的神经网络来实现未来短期车速的预测,分析未来车辆需求功率变化,同时借助全球定位系统规划一条通往目的地的路径,智能交通系统便可获取整个行程的交通流量信息,利用行驶里程和SOC实时动态修正等效消耗最小策略中的等效因子,实现能量管理策略的自适应性.基于MATLAB/Simulink软件,搭建整车仿真模型与传统的能量管理策略进行仿真对比验证.仿真结果表明,采用基于神经网络的工况预测算法能够较好地预测未来短期工况,其预测精度相较于马尔可夫方法提高12.5%,所提出的能量管理策略在城市道路循环工况(UDDS)下的氢气消耗比电量消耗维持(CD/CS)策略下降55.6%.硬件在环试验表明,在市郊循环工况(EUDC)下的氢气消耗比CD/CS策略下降26.8%,仿真验证结果表明了所提出的策略相比于CD/CS策略在氢气消耗方面的优越性能,并通过硬件在环实验验证了所提策略的有效性.

基于充电行为电量规划的自适应能量管理策略

为提高插电式混合动力汽车(PHEV)的燃油经济性,以并联式PHEV为研究对象,考虑驾驶员充电行为,提出基于充电行为电量规划和等效燃油消耗最小策略(ECMS)的自适应能量管理策略。构建了包含不同类型工况的组合工况。根据驾驶员的充电行为特征(充电频率、充电上限、放电下限)进行充电行为分析,并进行4类工况电量消耗与燃油消耗ECMS策略下的离线仿真数据获取。根据驾驶员充电行为以及离线数据进行SOC轨迹的规划。结果表明:在电池SOC初始值分别为0.9、0.6时,提出的能量管理策略相较于基于电量消耗维持的等效燃油消耗策略,整车燃油经济性分别提升7.87%和13.1%。

复合储能式装载机能量控制优化与仿真

针对工程车辆在机群作业下的能量管理问题,以复合储能式装载机为研究对象,利用Recurdyn-Edem联合仿真建立连续作业环境获取工况数据;分别以V型工况及集群作业下装载机单次循环工况油耗最少为目标,设计了基于等效油耗最小策略与规则相结合的控制策略,为了能够进一步提高全局工况的燃油经济性,使用遗传算法对等效油耗最小关键参数进行寻优,最后带入整车模型进行仿真验证。结果表明,V型工况与集群作业工况下,该控制策略相较于自适应神经模糊控制,燃油经济性分别提升了3.23%和4.26%;通过dSPACE进行硬件在环试验,试验与仿真结果基本一致,进而验证了优化结果的有效性。

氢能无人机等效消耗最小化策略设计

【目的】为了提高氢能混合动力固定翼无人机飞行过程中能源系统功率变化的稳定性以及燃料经济性。【方法】在传统等效消耗最小化策略理论的基础上引入一种考虑蓄电池组功率变化幅度对能量消耗影响的变等效因子。将此因子与原有等效因子加权相加,形成复合等效因子。建立了适用于复杂飞行工况的无人机混合动力仿真平台,研究了复合等效因子对等效消耗最小化策略控制效果的影响。【结果】结果表明,使用复合等效因子的等效消耗最小化策略可以有效降低能源系统的功率波动幅度,巡航飞行时氢燃料电池的功率波动幅度比传统等效消耗最小化策略降低了94.7%,飞行过程中蓄电池组SOC累计变化量降低了46%;在3.5 h的飞行任务中可节省193标准升氢气,提高了燃料的经济性。当蓄电池组SOC接近平衡值时,可以大幅减缓充电功率的变化率。改进后的等效消耗最小化策略有利于延长能源系统的使用寿命,提高燃料电池和蓄电池组的安全性。

混合动力汽车深度强化学习分层能量管理策略

为了提高混合动力汽车的燃油经济性和控制策略的稳定性,以第三代普锐斯混联式混合动力汽车作为研究对象,提出了一种等效燃油消耗最小策略(equivalent fuel consumption minimization strategy,ECMS)与深度强化学习方法(deep feinforcement learning,DRL)结合的分层能量管理策略。仿真结果证明,该分层控制策略不仅可以让强化学习中的智能体在无模型的情况下实现自适应节能控制,而且能保证混合动力汽车在所有工况下的SOC都满足约束限制。与基于规则的能量管理策略相比,此分层控制策略可以将燃油经济性提高20.83%~32.66%;增加智能体对车速的预测信息,可进一步降低5.12%的燃油消耗;与没有分层的深度强化学习策略相比,此策略可将燃油经济性提高8.04%;与使用SOC偏移惩罚的自适应等效燃油消耗最小策略(A-ECMS)相比,此策略下的燃油经济性将提高5.81%~16.18%。

基于工况识别的PHEV能量管理策略

为提升并联式混合动力汽车(parallel hybrid electric vehicle,PHEV)的燃油经济性,针对等效燃油消耗最小控制策略(equivalent fuel consumption minimum strategy,ECMS)在不同工况下适应性差的问题,以优化整车等效燃油消耗量为目标,设计基于工况识别算法的变等效因子ECMS能量管理策略。选取3类典型工况建立支持向量机分类模型,通过递归特征消除法对样本特征进行选择,采用鲸鱼算法对支持向量机进行参数优化,使用模拟退火算法分别对3类工况的ECMS等效因子进行离线全局最优求解,并分别存储于等效因子库中,通过训练好的支持向量机分类器对目标优化工况进行工况识别,不同类型的工况片段采用不同的等效因子进行转矩分配。仿真结果显示:相比于逻辑门限能量管理策略,基于工况识别算法的变等效因子ECMS能量管理策略的电池荷电状态(state of charge,SOC)变化量减少8.67%,节油率为13.11%;相比于优化前的ECMS策略电池SOC变化量减少3.47%,节油率约为6.63%。本文提出的基于工况识别算法的变等效因子ECMS能量管理策略可以有效地减少燃油消耗量,提升PHEV的整车经济性。

从能耗双控到碳排放双控政策下的企业适应策略

在能源环境政策由能耗双控向碳排放双控演变的宏观背景下,中国企业面临着环保压力与成本增加的挑战,不仅产品结构与市场受到影响,生产组织与管理模式的调整需求亦愈发迫切。为了提高自身对政策演变的适应性,企业应加大低碳技术研发和应用,实施清洁化改造,并主动承担社会责任,基于多项措施的综合实施为自身可持续发展目标的更好达成提供支持。

Design and optimization of equivalent consumption minimization strategy for 4WD hybrid electric vehicles incorporating vehicle connectivity

This paper presents an optimized equivalent consumption minimization strategy(ECMS) for four-wheel-drive(4 WD) hybrid electric vehicles(HEVs) incorporating vehicle connectivity. In order to be applicable to the 4 WD architecture, the ECMS is designed based on a rule-based strategy and used under the condition that a certain propulsion mode is activated. Assuming that a group of 4 WD HEVs are connected and position information can be shared with each other, we formulate a decentralized model predictive control(MPC) framework that compromises fuel efficiency, mobility, and inter-vehicle distance to optimize the velocity profile of each individual vehicle. Based on the optimized velocity profile, an optimization problem considering both fuel economy and battery state of charge(SOC) sustainability is formulated to optimize the equivalent factors(EFs) of the ECMS for HEVs over an appropriate time window. MATLAB User Datagram Protocol(UDP) is used in the codes run on multiple computers to simulate the wireless communication among vehicles, which share position information via UDP-based communication, and dSPACE is used as a software-in-the-loop platform for the simulation of the optimized ECMS. Simulation results validate the control effectiveness of the proposed method.

基于粒子群优化的模糊自适应等效油耗最小能量管理策略

为提高等效燃油消耗最小能量管理策略(ECMS)对不同工况的适应能力,提出一种基于粒子群算法优化的模糊自适应等效燃油消耗最小的能量管理策略(PSO-fuzzy A-ECMS)。以基于SOC反馈原理对等效因子进行比例调节方法为基础,针对仅依靠SOC反馈的等效因子调节方式存在一定局限性的问题,引入模糊控制以需求功率和SOC为输入对比例系数进行调节,利用粒子群算法优化模糊控制器中的隶属度函数,减少模糊控制在能量管理应用中对专家经验的依赖,最后在标准循环工况下进行仿真。仿真结果显示:相较于基于SOC反馈的等效因子修正方法,本文提出的PSO-fuzzy A-ECMS策略能够维持SOC在合理区间内变化,在燃油经济性和电池充放电平衡方面能够取得更好的控制效果。

混合动力重卡自适应等效燃油消耗最小化能量管理策略

为解决等效燃油消耗最小化策略的关键参数在不同工况下的动态调整,提出一种适用于混合动力重型汽车的自适应等效燃油消耗最小化策略(adaptive equivalent consumption minimization strategy,A-ECMS)。该策略以层次聚类算法得到的6种典型行驶工况为例,提出了一种基于神经网络工况识别算法。应用改进的混沌粒子群优化(chaosparticle swarm optimization,CPSO)算法优化特定驾驶循环下等效燃油消耗最小化策略(equivalent consumption minimization strategy,ECMS)的3个关键参数:等效因子、惩罚函数的比例因子和发动机起动车速阈值。提出了一种基于工况识别的新型自适应能量管理策略对关键参数进行优化,根据该重型卡车的传动系统构型,建立了车辆的纵向动力学模型,并通过仿真进行了验证。仿真结果表明复合工况驱动循环下的CPSO-ECMS和A-ECMS控制策略与传统等效燃油消耗策略相比,油耗分别降低了5.9%和8.9%。

融合工况预测的混合动力拖拉机自适应能量管理策略

针对传统等效燃油消耗最小策略(ECMS)下等效因子取值固定和工况适应性差的问题,提出了一种融合拖拉机工况预测的自适应等效燃油消耗最小策略(PA-ECMS)。以搭载混合动力液压机械无级变速动力总成的大马力拖拉机为研究对象,将ECMS策略应用于混合动力拖拉机的动力分配。首先,基于径向基(RBF)神经网络,建立了拖拉机工况预测模型,通过历史工况预测未来一段时间的工况信息;接着,结合电池荷电状态(SOC)反馈和预测的工况信息,对等效因子进行自适应调整;最后,在PA-ECMS策略框架下,对混合动力拖拉机的功率进行优化分配。仿真结果表明:与固定等效因子的ECMS策略和仅基于SOC反馈的自适应等效燃油消耗最小策略(A-ECMS)相比,采用所提策略时拖拉机在犁耕工况下的油耗分别降低了6.30%和2.55%,且具有更好的电量维持性能。

混合动力船舶等效油耗最小能量管理策略

为了降低混合动力船舶的燃油消耗,同时解决传统等效油耗最小能量管理策略(ECMS)易导致动力设备处于恶劣工况的缺点,提出一种利用逻辑门限值规则对混合动力系统工作模式进行预识别的改进ECMS,并采用改进的蚁群算法对充放电等效因子进行离线优化。在船舶典型航行工况下,通过MATLAB/Simulink建立的船舶仿真模型进行逻辑门限值能量管理策略、等效因子分别取经验值和优化值的改进ECMS的仿真分析。结果表明:等效因子寻优后的改进ECMS有更好的燃油经济性,同时也利于保证电池荷电状态(SOC)平衡和动力设备的效率。

双参数优化的混合动力汽车能量管理策略研究

为了挖掘新型功率分流式混合动力汽车能量管理策略的节能潜力,设计了一种双参数优化的等效油耗最低策略(AD-ECMS)。首先,提出并验证了发动机起停规则对整车经济性的影响。基于此,优化出一种改进型粒子群算法(ISPSO),根据对等效油耗和电量的实时跟踪,实现对最优等效因子及发动机起停规则的双参数求解。随后,提出了一种双参数优化的等效油耗最低策略,利用模糊控制器识别当前工况特征,通过在线更新等效因子和发动机起停规则,实现经济性能量管理。最后,与ECMS策略、A-ECMS策略进行仿真对比及实验验证,结果表明:AD-ECMS策略在整车经济性和电量平衡性上,都具备更好的控制效果。

TTR汽车等效燃油消耗最小的能量管理策略研究

为改善通过路面实现动力耦合与电池充电的TTR汽车经济性,分析TTR汽车结构及工作模式,基于等效油耗最小的能量管理策略(ECMS),计算固定等效因子(CECMS);为使电池SOC保持稳定并控制发动机工作于低燃油消耗区,将行驶所需发动机等价总转矩及电池SOC模糊化,制定等效因子的模糊控制规则,而提出模糊自适应等效燃油消耗最小控制策略(FAECMS)。利用MATLAB/Simulink建立包含TTR汽车动力学的CECMS、FAECMS模型,选取FTP75、CLTC、WLTP 3种标准工况,当电池SOC初始值为60%时进行仿真计算,得出FAECMS相对CECMS在3种工况下电池SOC更稳定,并分别节约燃油5.5%、2.6%、8.3%。

多旋翼混合动力无人机自适应能量管理策略仿真

为提高多旋翼混合动力无人机的运行稳定性、输出动力性和能量利用率,利用GT-Power和Simulink进行模型联合搭建,对比基于规则的能量管理策略及等效燃油最小消耗能量管理策略(Equivalent consumption minimization strategy,ECMS),设计开发了基于BP(Back propagation)神经网络优化的自适应ECMS(Adaptive-ECMS,A-ECMS)。仿真研究表明:A-ECMS在运行稳定性上,整体工况转速波动率为7.74%,较基于规则策略和ECMS都有明显降低;A-ECMS在复合扰动下和随机紊流下转速波动率分别为8.32%、7.18%,与基于规则策略和ECMS相比在突发工况下运行更为稳定。A-ECMS能有效提高混合动力系统动力性能,使发动机处于经济工况10 kW;可根据荷电状态(State of charge,SOC)变化实时对电池功率进行调整。A-ECMS平均燃油消耗率为297.585 g/(kW⋅h),整体燃油消耗量为3755.31 g,与基于规则策略和ECMS相比明显较低,在各工况下运行时发动机工况点集中于燃油经济区,有效提高了系统经济性。