电动汽车多功能充电系统设计

介绍一款基于单片机控制的电动汽车多功能充电系统的设计过程.采用开关电源技术,具有体积小、重量轻、充电效率高的优点.选用了绝缘栅双极晶体管(IGBT)构成全桥逆变器,逆变后整流滤波得到的直流电,纹波小、控制精度高,能快速安全稳定的为蓄电池充电,充电过程自动进行,无需看守.根据不同类型的蓄电池的最佳充电曲线,从软件上设计了相应的充电方法,使充电过程在最佳方式下进行.     

基于MPPT的太阳能充电控制器的设计

本文设计了一种具有MPPT功能的光伏发电充电控制器。通过单片机检测蓄电池充电电压、充电电流的大小,自动切换充电器的工作状态,有效地提高了蓄电池的寿命。在光照条件不足时,蓄电池的电压,电流未超出给定值,开启MPPT功能,保证整个系统最大效率的充电。经matlab仿真,该设计具有可行性。     

太阳能家用照明装置单片机自动控制器

为了缩短充电时间,提高充电效率,太阳能家用照明装置自动控制器能在充电过程中实时跟综蓄电池充电电压、电流、温度和太阳能蓄电池的电压,通过单片机硬件软件资源动态调整蓄电池充电电压、电流和控制用户照明装置,使蓄电池充电效率达到最佳效果,太阳能利用率达到最高。     

4节蓄电池串联智能充电器的设计

本文针对4节蓄电池串联充电时容易出现过充或欠充现象,设计了一种带均衡功能的智能充电器,同时对充电过程中的电池电压和充电电流提出了新的检测思路;并根据锂电池的充电特性曲线设计了充电器的软件.该充电器具有均衡作用,充电效率高.     

矿用铅酸蓄电池高频智能快充充电器控制系统研究

针对矿用铅酸蓄电池充电器,研究了一款高频智能快充充电器的控制系统,由多环节功率变换单元组成,能量双向流动。在分析其工作原理的基础上,基于DSP给出了系统的硬件电路、软件实现方案及电路结构,采用移相PWM控制算法,实现了变电流智能快速充电放电方法。实验表明了该充电器控制系统设计的可行性和正确性,可自动匹配最佳充电放电曲线,实现了快速充电放电,性能指标优越,可以在行业内推广应用。     

基于智能控制的锂电池快速充电方法研究

针对电动汽车不能实现快速的电能补充以及电池充电过程中存在的非线性、时变性和不确定性导致充电过程不稳定的问题。本文设计了一种基于模糊自适应PID控制的快速充电方法,在充电过程中引入了电压降补偿,并分别对锂电池充电系统的电流内环和电压外环进行控制,使实际充电曲线更加接近马斯曲线。理论分析和仿真实验表明,该充电方法加快了蓄电池充电速度,且具有稳定性好等优点。     

煤矿电机车蓄电池充电机技术改造

针对充电机使用中存在的实际问题,对煤矿井下蓄电池充电设备进行技术改造,采用CDK-Ⅲ型蓄电池充电机控制器代替原有插件,使改造后的充电机能自动选择充电电流进行充电,降低温升,减少酸雾,有利于充电工身体健康,比常规充电节能,充电时间缩短,避免电池受损,延长电池寿命。     

基于UC3909的太阳能充电方案

随着全球化石燃料能源的大量减少,开发和应用新能源已成为解决全球能源问题的重要举措之一。该文给出了一种利用太阳能电池板,以充电管理芯片UC3909为核心的蓄电池充电方案。按照铅酸蓄电池的储能方法,该设计可以实现对蓄电池进行涓流、恒流、恒压、浮充四阶段充电,在充电过程中还可以对充电电压和充电电流进行实时监控,能够实现对蓄电池可靠精确地充电,提高蓄电池的使用寿命。     

一种新型快速充电体制的研究:以充电电流接受力控制的充电

近年我们研究的一种新的充电方法,能在较短的时间内使蓄电池充足电,充电速率为常规充电的15倍左右。这种充电方法仅提供电池一个能接受的电流量,容量充足则自动断电。因此,不会充电不足,也无过充危险,宏观上没有气体产生,仅有微小的温升,实验证明,这种新的充电体制有利于延长Ni—Cd蓄电池寿命。较之常规充电更适合要求。本文论述了GY—1—0.5密封镍镉蓄电池快速充电机的快充原理。     

基于光强的太阳能自动跟踪装置及其蓄电池充电优化控制

设计了一种太阳能自动跟踪装置,此装置能够根据光的强弱自动转到光强最大的方向,从而提高太阳能利用率。所设计的自动跟踪装置主要由太阳能电池板蓄电电路、单片机主控电路、液晶显示电路和光敏采样电路四个模块构成,其中单片机主控电路是根据四个光敏电阻输出电压的差值,控制两舵机的转动使得太阳能电池板始终面朝光线最强的方向,并监控蓄电池和太阳能电池的状态,通过控制S8050三极管达到控制太阳能电池板向蓄电池浮充充电的目的,控制蓄电池的充放电,提高太阳能充电效率。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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