Parameters matching and optimization of parallel hybrid electric vehicle powertrain

Aiming at the development of parallel hybrid electric vehicle （PHEV） powertrain, parameter matching and optimization are presented, According to the performance of PHEV, the optimization range of engine, motor, driveline gear ratio and battery parameters are determined. And then a two-level optimization problem is formulated based on analytical target cascading （ATC）. At the system level, the optimization of the whole vehicle fuel economy is carried out, while the tractive performance is defined as the constraints. The optimized parameters are cascaded to the subsystem as the optimization targets. At the subsystem level, the final drive and transmission design are optimized to make the ratios as close to the targets as possible. The optimization result shows that the fuel economy had improved significantly, while the tractive performance maintains the former level.

Matching and Simulation of Power Parameters of Electric Transporter based on Cruise Software

In view of the characteristics of warehouse or freight yard carrying out transfer and loading conditions,the performance parameter matching of the power system of an electric transfer vehicle was studied,and the driving motor and power battery of the key components of the vehicle were reasonably selected.Cruise software was used to simulate the loading process of the vehicle.The results show that the performance design of the power system of the electric transport vehicle and its key components is reasonable,meeting the requirements of maximum speed,climbing performance and starting driving performance,and providing a reference and credible basis for the design of the power system of the vehicle.

The Electrical and Mechanical Alignment and Accuracy Detection of Numerial Control Machine Tool

In the work of numerical control reformation of general machine tool, the installation and debugging of machine tool is a crucial part. For the C6132 machine tool, and make the use of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been used to finish a series of tailing in the work of numerical control reformation of general machine tool. In this paper, the detailed process of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been demonstrated, meanwhile, the specific operational approach of these work programs has been discussed. Therefore, the present results provides essential reference and approach for the numerical control reformation of general machine tool.

Failure mechanism and influencing factors of cement sheath integrity under alternating pressure

The failure of cement sheath integrity can be easily caused by alternating pressure during large-scale multistage hydraulic fracturing in shale-gas well.An elastic-plastic mechanical model of casing-cement sheath-formation(CSF)system under alternating pressure is established based on the Mohr-Coulomb criterion and thick-walled cylinder theory,and it has been solved by MATLAB programming combining global optimization algorithm with Global Search.The failure mechanism of cement sheath integrity is investigated,by which it can be seen that the formation of interface debonding is mainly related to the plastic strain accumulation,and there is a risk of interface debonding under alternating pressure,once the cement sheath enters plasticity whether in shallow or deep well sections.The matching relationship between the mechanical parameters(elastic modulus and Poisson's ratio)of cement sheath and its integrity failure under alternating pressure in whole well sections is studied,by which it has been found there is a“critical range”in the Poisson's ratio of cement sheath.When the Poisson's ratio is below the“critical range”,there is a positive correlation between the yield internal pressure of cement sheath(SYP)and its elastic modulus.However,when the Poisson's ratio is above the“critical range”,there is a negative correlation.The elastic modulus of cement sheath is closely related to its Poisson's ratio,and restricts each other.Scientific and reasonable matching between mechanical parameters of cement sheath and CSF system under different working conditions can not only reduce the cost,but also protect the cement sheath integrity.

Powertrain parameter matching and optimal design of dual-motor driven electric tractor

The rationality of powertrain parameter design has a significant influence on the traction performance and economic performance of electric tractor.At present,researches on powertrain parameter design mainly focus on electric vehicles,and electric agricultural machinery draw much less attention.Therefore,a method of powertrain parameter matching and optimization design for electric tractor was proposed in this paper,which was based on dual-motor coupling drive mode.The particle swarm optimization(PSO)algorithm based on mixed penalty function was used for parameter optimization.Parameter optimization design was programmed using MATLAB.A simulation dynamic model with optimization design variables of electric tractor powertrain was established based on MATLAB/Simulink.Compared with the simulation results before optimization,the objective functions were optimized and the traction performance of electric tractor was improved,which indicated the effectiveness of the proposed method.

Parameters optimum matching of pure electric vehicle dual-mode coupling drive system

As an important development direction of pure electric vehicle drive system,the distributed drive system has the advantages of compact structure,high transmission efficiency,and flexible control,but there are some serious problems such as high performance requirements to the drive motors,complex control strategies,and poor reliability.To solve these problems,a two motors dual-mode coupling drive system has been developed at first,which not only has the capacity of two-speed gear shifting,but also can automatically switch between the distributed drive and the centralized drive by means of modes change control.So,the performance requirements to the drive motors can be reduced,the problem of abnormal running caused by the fault of unilateral distributed drive systems also can be resolved by replacing the drive mode with centralized drive.Then,the system parameters primary and the optimum matching under the principle of efficiency optimization have been carried out,which makes the drive system achieve predetermined functions and meet the actual demands of different operating statuses.At last,the economic comparison of a pure electric vehicle installation with a dual-mode coupling drive sytem,a single-motor centralized drive system or a dual-motor distributed drive system in the simulation conditions has been completed.Compared with other systems,the driving range of the electric vehicle driven by the designed system is significantly increased,which proves the better efficiency and application value of the system.

Determination of rock mass integrity coefficient using a non-invasive geophysical approach

Determination of rock mechanical parameters is the most important step in rock mass quality evaluation and has significant impacts on geotechnical engineering practice.Rock mass integrity coefficient(KV)is one of the most efficient parameters,which is conventionally determined from boreholes.Such approaches,however,are time-consuming and expensive,offer low data coverage of point measurements,require heavy equipment,and are hardly conducted in steep topographic sites.Hence,borehole approaches cannot assess the subsurface thoroughly for rock mass quality evaluation.Alternatively,use of geophysical methods is non-invasive,rapid and economical.The proposed geophysical approach makes useful empirical correlation between geophysical and geotechnical parameters.We evaluated the rock mass quality via integration between KV measured from the limited boreholes and inverted resistivity obtained from electrical resistivity tomography(ERT).The borehole-ERT correlation provided KV along various geophysical profiles for more detailed 2D/3D(two-/three-dimensional)mapping of rock mass quality.The subsurface was thoroughly evaluated for rock masses with different engineering qualities,including highly weathered rock,semi-weathered rock,and fresh rock.Furthermore,ERT was integrated with induced polarization(IP)to resolve the uncertainty caused by water/clay content.Our results show that the proposed method,compared with the conventional approaches,can reduce the ambiguities caused by inadequate data,and give more accurate insights into the subsurface for rock mass quality evaluation.

氢电-锂电通勤飞机分布式推进系统匹配设计

针对通勤类飞机总体设计参数和飞行任务剖面需求,根据氢电-锂电推进系统架构方案,提出了推进系统参数匹配方法和能源动态平衡管理策略。以19座级通勤飞机作为验证对象,对其动力装置和储备能源进行了选型和管理研究。根据选型的分布式推进气动布局方案,进一步采用全析因试验设计方法分析了螺旋桨转向对飞机气动特性的影响,获得了有利于飞机巡航状态的螺旋桨转向配置方案。

电动叉车动力传动系统优化设计

为了提高电动叉车的续航里程及动力性能,提出了加装两挡变速器的传动方案。首先,基于驱动电动机的外特性与效率特性提出了两挡传动系统参数匹配方法;其次,以某型电动叉车为研究对象,对其驱动系统进行了改进:在不改变驱动电动机各项参数的基础上,将传动系统由一挡改为两挡,并对主减速比及变速器的两挡减速比进行匹配;最后,利用ADVISOR软件对电动叉车进行了平衡重式叉车循环工况仿真分析。结果显示,在不改变驱动电动机各项参数的基础上加装两挡变速器,可提升整个电动叉车的动力性和经济性;车速由0加速到最高车速的时间缩短了0.4s,满载爬坡度提高了2.5%,2小时叉车等效工况循环的电池能耗降低了3.5%。

微型电动汽车正面碰撞约束系统匹配研究

目前对微型电动汽车相关研究逐渐增多,但碰撞安全性能方面的研究相对较少。基于国内某款微型电动汽车在进行49 km/h正面碰撞后车内Hybrid Ⅲ 50th男性假人伤害程度较高的问题,对该车约束系统的参数匹配进行优化处理。参考相关规范对驾乘人员的保护要求,以仿真分析结果中的头部伤害指标HIC、头部累积3 ms合成加速度、加权综合损伤数值WIC为研究指标,进行极差分析来综合选取参数及水平值;通过正交试验进行优化设计仿真,最终得出最佳约束系统的最佳参数匹配方式,使得微型电动汽车在发生碰撞事故时驾驶员头部位置的伤害得到降低,同时维持或降低胸部和下肢伤害水平,综合损伤也得到降低。结果表明优化后的该约束系统可达到对驾驶员最优的保护效果。

功率分流式混合动力汽车整车参数匹配与优化研究

针对功率分流式混合动力汽车,首先根据整车设计参数及动力性能目标要求,分别对电机、动力电池组、发动机、主减速器和行星排等传动系统部件进行参数匹配,并运用AVL-Cruise软件建立目标车辆整车模型;其次在满足动力性能目标的前提下,运用AVL-Cruise和Isight软件搭建联合仿真模型,分别采用粒子群优化算法和多岛遗传算法,将行星排特征参数和主减速器传动比作为优化参数,百公里油耗和电耗加权之和作为优化目标进行优化研究,并对比分析2种优化算法的计算结果来获得兼顾动力性能和经济性的最优结构参数,为研究功率分流式混合动力汽车传动系统提供理论依据。

油电混合动力船舶动力系统研究

为了响应国家对航运业绿色可持续发展的需求,以某小型油电混合动力客船为研究对象,进行动力系统研究。根据船舶基本参数与设计指标,给出混合动力系统总成方案。在满足船舶动力性指标要求的前提下,对船舶混合动力系统进行参数匹配;并进一步提出了油电混合动力船舶能量控制策略,最后在混合动力实验平台上进行仿真试验验证。实验结果表明,相同工况下,混合动力船舶会比柴油发动机作为主机的船舶消耗更少的燃料,可以有效提高船舶的经济性并改善其排放性能。

重型商用车双电驱动桥构型方案设计与参数匹配方法研究

重型商用车电动化是解决其能耗高、排放有害气体多等问题的主要途径之一,而电驱动系统构型方案设计和参数匹配是重型商用车电动化的基础。以一种重型商用车的双驱动桥为研究对象,对驱动桥的电驱动构型方案设计和参数匹配问题进行研究。分析对比各类电驱动方案的特点,确定双电驱动桥的电驱动方案,并确定了驱动电动机数量以及变速装置的挡位数;在构型方案的基础上,根据车辆的功能和性能要求,计算确定了电驱动桥中主要部件的结构性能参数,包括驱动电动机的功率、转矩和转速,变速传动装置的传动比,以及动力电池的电压和容量;基于上述构型和参数,建立双电驱动桥重型商用车的动力学模型,对车辆的动力性和经济性进行了仿真分析。仿真结果表明,车辆的最高车速能够达到100 km/h,最大爬坡度能够达到30%,续航里程超过300 km,说明所提出的构型和匹配的参数满足车辆性能的要求。相关研究可为重型商用车的电动化提供理论和技术支持。

增程式电动汽车动力系统参数匹配建模仿真分析

增程式电动汽车是以纯电能驱动的车辆,通过动力蓄电池和一个小型的增程器(Auxiliary Power Unit)为车辆提供电能,在增加了车辆续航里程的同时,工况适应性也随之提高,被评为目前具有较高研发前景的新能源汽车[1]。本文以城市SUV车型的增程式电动汽车为需求目标进行研究。根据整车参数及制定的控制策略,基于AVL Cruise软件为平台建立性能仿真模型;建立Simulink控制策略模型;分别在短途行驶模式和长途行驶模式下选定符合相应模式的行驶工况进行联合仿真分析。结果表明,整车动力性及续航里程均能达到初始的设计目标,为增程式电动汽车的技术拓展和多样的控制策略提供可行性方案。

纯电动汽车动力参数匹配及优化

在全球能源结构转型中,纯电动汽车已经成为交通运输领域重要的发展方向。作为纯电动汽车的重要组成部分,传动系统的参数匹配对于汽车的动力性和经济性有着举足轻重的作用。通过对纯电动车传动系统参数的合理匹配,实现车辆动力性与经济性的双重提升。这不仅可以改善车辆的加速性能、最高车速和爬坡能力,还可以提高车辆的续航里程和降低使用过程中的能耗费用。此外,通过对参数的合理匹配,车辆在降低自重的同时,也可以提高经济性。通过对纯电动汽车传动系统的研究,对其参数匹配和优化计算的方法进行了探讨。

三钢纯电自卸车动力系统选型与实践

本文根据三钢厂内运输工况和目标参数,对8×4纯电自卸车动力选型匹配,并建立模型对该方案的动力性和经济性进行分析,为厂内安全运输提供了实用性指导。

Parameter identification of partially covered piezoelectric cantilever power scavenger based on the coupled distributed parameter solution

Among the various techniques of power scavenging,piezoelectric energy harvesting usually has more power density.Although piezoceramics are usually more efficient than other piezoelectric materials,since they are very brittle and fragile,researchers are looking for alternative materials.Recently Cellulose Electro-active paper(EAPap)has been recognized as a smart material with piezoelectric behavior that can be used in energy scavenging systems.The majority of researches in energy harvesting area,use unimorph piezoelectric cantilever beams.This paper presents an analytical solution based on distributed parameter model for partially covered pieoelectric cantilever energy harvester.The purpose of the paper is to describe the changes in generated power with damping and the load resistance using analytical calculations.The analytical data are verified using experiment on a vibrating cantilever substrate that is partially covered by EAPap films.The results are very close to each other.Also asymptotic trends of the voltage,current and power outputs are investigated and expressions are obtained for the extreme conditions of the load resistance.These new findings provide guidelines for identification and manipulation of effective parameters in order to achieve the efficient performance in different ambient source conditions.

温湿度对电能表元器件寿命的影响研究

文章旨在研究工作温湿度对电能表元器件寿命的影响,并分析其相关性。通过对电子元器件的工作年限失效机理、性能参数老化规律、失效率和寿命基础数据的研究,建立关键元器件寿命模型。研究结果表明,温湿度对电能表元器件寿命有显著影响,为电能表设计和维护提供了重要参考。

轻度混合动力汽车动力性能仿真及动力系统参数匹配研究

介绍了采用起动机/发电机/电动机一体化技术的ISG(Integrated starter/generator)型混合动力汽车动力传动系统结构及控制策略,建立了装备双模式无级变速传动系统的ISG型混合动力汽车起步加速过程的动力学模型,并进行了计算机仿真。提出了轻度混合动力汽车动力系统的匹配设计方法,分析了电动机峰值功率、启动转矩和发动机启动转速对整车动力性能和传动系统转矩响应的影响,为轻度混合动力汽车总体设计提供了理论依据。

并联混合动力电动汽车动力系统的参数匹配

针对典型的转矩复合结构并联混合动力电动汽车(PHEV),提出了用工程分析与仿真校验相结合的方法,对其动力系统中发动机功率、电动机参数、传动系速比和电池参数等主要参数进行匹配的原则、步骤,并通过实例加以说明和验证。