基于融合算法的车载锂电池荷电状态估计

动力电池的荷电状态(State Of Charge,SOC)是电池管理系统(Battery Management System,BMS)的关键内容。本文采用遗传算法(Genetic Algorithm,遗传算法)和BP神经网络(BP neural network)相结合的方法对动力锂电池进行荷电状态估计,通过从NASA中提取的锂电池充放电数据进行训练和测试得到的SOC估计值与真实值的对比分析,基于这种融合算法的锂电池SOC估算误差在2.5%以内,验证了提出的电池估计方法的有效性。     

基于扩展卡尔曼滤波算法的燃料电池车用锂离子动力电池荷电状态估计

针对燃料电池汽车用锂离子动力蓄电池建立一个简单物理模型和一个复杂物理模型,它们分别以不同等效电路来描述电池的动态特性,然后将这两个物理模型中各物理量和状态量之间的关系表达成离散化的状态空间方程.在此基础上,利用在燃料电池汽车实车运行过程中测得的包括电流、电压等数据,基于扩展卡尔曼滤波算法对锂离子动力电池的荷电状态进行估计,并对利用两种模型进行估计的结果进行比较分析.分析结果表明,基于电池等效电路模型的卡尔曼滤波电池荷电状态估计算法是有效的,并且电池模型对估计结果的影响较大,利用精确的电池模型容易达到较高的估计精度.     

基于不同模型下EKF算法的锂离子电池SOC估计

动力电池的准确建模及荷电状态(SOC)的精准估计对提高电池的利用效率、延长使用寿命具有重要意义。本文对锂离子电池进行等效电路模型的建立并通过HPPC测试对模型进行参数辨识。利用Matlab软件,基于两种模型开展扩展卡尔曼滤波算法下的电池SOC估计精度对比实验研究。结果表明,在同一实验条件下,EKF-Ah SOC估计方法能够有效提高电池SOC的估计精度;与Rint模型相比,基于Thevenin模型的EKF-Ah SOC估计精度得到显著提高,SOC估计最大绝对误差为1.91%。     

基于电化学阻抗谱的退役动力电池荷电状态 和健康状态快速预测

针对现阶段检测退役动力电池健康状态存在的耗时长、精度低和能耗大等问题,提出了一种基于电化学阻抗谱(EIS)的电池荷电状态(SOC)和健康状态(SOH)的快速预测方法。通过对退役磷酸铁锂动力电池在不同SOH、不同SOC和不同温度下的EIS测试和分析,建立了EIS等效电路模型。然后,利用常相位元件参数与退役动力电池SOC和SOH之间的关系,建立数学模型,实现对退役动力电池SOC和SOH的快速估计。验证实验表明,利用这种方法,可以大大减少测试时间至20min以内、节约能源以及实现对未知荷电状态和健康状态的电池的快速估计,预测误差在4%以内。     

利用双卡尔曼滤波算法估计电动汽车用锂离子动力电池的内部状态

以电动汽车的研发为背景,建立用于电动汽车中作为辅助动力源的锂离子动力蓄电池的等效物理模型及其离散形式的状态空间方程,然后分别介绍如何基于卡尔曼滤波算法在线估计电池内部的荷电状态和寿命状态。在此基础上,介绍利用双卡尔曼滤波算法同时在线估计荷电状态和寿命状态的算法原理,并设计出相关的电池测试试验,利用在此试验过程中所采集的包括电流、电压等数据对电池的内部状态进行估计。对试验结果的分析表明,利用双卡尔曼滤波算法在线估计电池内部状态是有效的,并且估计精度也相对较高,可以较好地反映电池内部的真实状态。     

镍氢动力电池管理系统研究

介绍对动力电池管理系统的研究,分析动力电池管理系统的组成以及该系统的难点。着重讨论电池组均衡控制、荷电状态(SOC)估计方法和电磁兼容性设计等三个关键问题,并指出纯电动汽车和混合电动汽车电池管理系统设计的差异。     

电动汽车动力电池SOH估计方法探讨

实时估计电动汽车动力电池健康状态(State of Health,SOH),对于充分保证每个电池组的充/放电性能,延长整个电池组的寿命具有重要意义。作为电池管理系统的重要组成部分,相比于电池荷电状态(State of Charge,SOC)和电池均衡系统的研究,SOH估计方法的研究明显落后。简单介绍了SOH的定义及影响因素,按照离线估计方法和在线估计方法进行分类,探讨了常见的SOH估计方法。最后展望了SOH估计方法的发展趋势,指出基于卡尔曼滤波的在线估计和智能学习神经网络的方法将是未来的主流方法。     

遗传算法优化神经网络整包电池SOC估计模型

针对Back Propagation(BP)神经网络建立的动力电池荷电状态（State of Charge，简称SOC）估计模型存在的精度、稳定性等问题，使用遗传算法（Genetic Algorithm，简称GA），对SOC估计网络模型进行优化。使用以轮盘赌算法配合最佳个体保存法做为遗传算法核心选择算法，避免传统选择算法中最佳个体可能丢失的情况。实验对象选用新能源氢电混动重卡4X2/6X2T FCV的辅助动力电池包。模型考虑了环境温度、放电电压、放电倍率以及直流内阻的影响，对不同隐含层数量对模型估计精度的影响进行了对比分析。测试结果表示，使用遗传算法优化后的神经网络SOC估计模型的精度和稳定性得到大幅提升。     

动力电池管理系统核心控制策略开发

插电式混合动力汽车具有电池荷电状态(SOC)使用范围大、整车的工作模式多、用户使用情况复杂等特点,且磷酸铁锂的电池单体电压曲线相对于三元材料的锂离子电池单体曲线更加平坦,低温充电能力差等,因此对锂离子动力电池管理系统的核心功能和性能提出了比纯电动汽车和混合动力汽车更高的要求。开发基于AH积分和静置后上电电压修正以及车载充电机充电修正的SOC估算策略;测试充放电许用功率曲线,开发了动力电池故障、低温低电量下充放电许用功率估算策略。目前东北示范的某型号汽车均采用了此控制策略,整车在各种不同复杂工况、工作模式和高、低温环境条件下运行状态良好,保持较低的动力电池故障率,能够满足示范运营的要求。     

基于卡尔曼滤波的电动汽车电池SOC估算方法研究

荷电状态SOC(State of Charge)是描述电动汽车动力电池状态的关键参数,对其进行估计,可以防止电池过充过放、有助于充分发挥电池中的能量、延长电池的使用寿命,是实现电池高效管理的关键技术之一。论文用卡尔曼滤波法对其进行估计,克服了安时法确定SOC初值难和存在累计误差的问题,易于工程实现,具有很好的实用价值。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.