嵌入式铅酸蓄电池组在线监测系统的设计

介绍了铅酸蓄电池的基本工作原理,分析了国内外铅酸蓄电池组监测技术的研究现状,设计了一种铅酸蓄电池组在线监测装置,实现对蓄电池组性能参数和状态的实时监测,为电池安全运行及日常维护工作提供主要的数据依据,对保证蓄电池机械的技术效能具有重要的意义。     

具有CAN总线接口的蓄电池在线监测装置

本文介绍了一种具有CAN总线接口的蓄电池在线监测装置，该装置是以单片机为核心的智能仪器，它能够完成对蓄电池组中每一只蓄电池的在线监测，可测量电池组的充，放电电流和电池组的自放电率，使用本装置可以方便组成CAN总线蓄电池数据采集，监测系统，可大大提高在线监测效果，进一步提高电池的可靠性。     

变电站蓄电池在线维护技术研究

介绍了一种用于变电站的蓄电池在线检测和在线维护管理系统,可提前对蓄电池潜在隐患做出分析和预测,实现直流系统蓄电池组故障的快速筛查、蓄电池组在线维护、蓄电池组在线活化等工作的一键式操作;能够为无人值守智能变电站直流蓄电池组的运行、监测、维护、施工、抢修等措施提供决策保障,提高智能变电站运行的可靠性。     

蓄电池与直流系统的重要性分析

蓄电池是变电站内直流系统的重要组成部分,它的工作原理是将电池中的化学能与电能相互转换。一般情况下,蓄电池处于浮充状态,变电站的二次负荷由交流电源经过整流后提供直流电源。当交流系统发生故障失电后,直流系统才切换为蓄电池进行直接供电。如果蓄电池维护不当,在发生事故时不能提供电源,将可能引起事故范围扩大。现对直流系统进行介绍,重点分析蓄电池在直流系统中的作用,指出必须加强蓄电池的日常监测和维护。     

浅谈电力系统阀控密封铅酸蓄电池的使用维护

详细介绍了电力系统阀控密封铅酸蓄电池的特点及影响蓄电池寿命的因素,阐述了蓄电池的一般维护管理及其管理和维护的改进措施。通过加强对电力系统用蓄电池的维护和研究,增强直流系统的稳定性,同时查找日常维护中的不足,达到增强供电可靠性,避免发生由于直流备用电源引起供电事故的目的。     

变电站蓄电池浮充电运行研究

首先介绍了蓄电池浮充的概念，然后以阀控密封式蓄电池为例阐述了其工作原理和特点，最后分析了影响变电站阀控蓄电池运行的因素并提出了相应的解决措施。     

铅酸蓄电池充放电的监测和控制

随着我国经济的发展,对供电系统的稳定性要求越来越提高,进而提高了对变电站蓄电池及直流电源的要求。我国电力系统变电站所使用的蓄电池维护技术成本较高,效果也不太理想,最终影响了蓄电池的性能。本文分析了铅酸蓄电池充放电的监测和控制指标、蓄电池在线监测系统组成及系统应用的实际效果。     

一种基于低压蓄电池的电力系统直流操作电源研究

传统的电力系统操作电源通常采用多节电池串联组成的蓄电池组作为后备电源,技术成熟可靠,但电池的维护较为复杂,成本较高。鉴于此,提出了一种新的电力系统操作电源方案,不采用蓄电池串联,而是由多组采用低压蓄电池的供电模块并联构成,每个供电模块包括一台将电网交流电变换为低压直流电的电源变换器、一只单节低压蓄电池和一台将低压直流电变换为操作母线电压的供电变换器。该系统具有模块化程度高、容量配置灵活、可在线视情维护电池等优点。现首先简要介绍传统直流操作电源的基本要求和组成,分析其存在的问题,然后提出新的系统结构并分析其特点,最后介绍研制的系统样机及实验情况,验证了新系统的可行性和优点。     

基于EKF的蓄电池荷电状态在线估算

针对电力系统迫切需要快速、准确估算蓄电池荷电状态的需求,在分析传统SOC估算方法不足的前提下,基于扩展卡尔曼滤波算法进行蓄电池的实时在线估算及模型修正,对蓄电池的放电数据建立相关模型簇,并通过实验验证该方法的有效性。     

阀控式密封铅酸蓄电池的应用和维护

简要介绍了在电力系统厂站广泛运用的阀控密封蓄电池的良好性能及密封机理，并橄据生产和应用实践，阐明了阀控密封蓄电池的使用和维护方法，对提高蓄电池的使用寿命，保证直流系统安全稳定可靠供电有较大的帮助。     

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...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

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.     

RLS and LMS blind adaptive multi-user detection method and comparison in acoustic communication

RLS and LMS blind adaptive multi-user detection algorithm and multi-user detector was proposed to solve the problem of multi-user signal detection problem encountered in underwater acoustic communication networks.In simulation analysis,RLS and the LMS blind adaptive multi-user detector were designed and tested for synchronous and asynchronous multi-user communication process.The results of SIR comparison and MMSE comparison show that,both of the two methods can realize blind adaptive detection when any user change in multi-user communication,during this process,the training communication sequences are not needed.The RLS algorithm has about 5 dB higher in SIR compared with LMS algorithm,and the convergence velocity of RLS algorithm is also higher than LMS algorithm when the communication users change.RLS algorithm has better ability in multi-user detection than that of LMS algorithm,and it has great attraction and guiding significance for solving the problem of multiple access interference(MAI) in multi-user communication.     

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...