超级电容器改善汽车启动性能

提出并分析了在汽车启动时蓄电池存在的问题，介绍了超级电容器的原理和特性，采用超级电容器与蓄电池并联改善汽车启动性能。     

16V／58F iMOD：超级电容器模块

Ioxus公司推出16V／58FiMOD系列超级电容器模块16V／58FiMOD超级电容器模块，旨在提供面向可再生能源发电系统的风电机组桨距控制、启动系统、汽车子系统、备用电源／不间断电源（UPS）／不间断运行以及功率调节等应用。     

超级电容器替代后备电池保护电源故障的分析

工作中的电子设备突遇电源故障时,通常需要启动后备电池对设备进行保护,本文在简单分析了超级电容器的特性、工作原理及如何选择合适电容器之后,利用集成电路LTC3225对两个串联的超级电容器进行充电,最终实现了超级电容器替代后备电池对电源故障进行保护。     

超级电容与锂电技术路径之争:广阔天地,并行不悖

正欧盟于2013年10月正式启动石墨烯旗舰项目(FET),利用高强度、高导电石墨烯薄膜材料提升电容器物理性能为其探索方向之一,并取得阶段性成果。超级电容在某些特定应用场景优势明显。相较于化学电池,超级电容具有瞬间释放大功率、使用寿命长,低温性能好等优势,广泛应于新能源汽车的某些特定领域。如Maxwell生产的超级电容器主要应用于混合动力客车制动能量回收系统、轨道交通的车载储能系统以及重型卡车的启动电源等方面。但其最大瓶颈为能量密度低(工业化应用的一般为蓄电池的5-15%),较难作为动力来源单独提供能源,未     

我国启动超级电容器技术标准的研制工作

正日前,由中国电子工业标准化技术协会超级电容器标准工作组主办的"超级电容器行业技术、标准及产业应用研讨会"在浙江宁波举行。会议围绕《超级电容器分类及型号命名方法》、《动力型超级电容器电性能测试方法》、《超级电容器术语》、《超级电容器充电器通用技术要求》     

Maxwell高性能‘D-CELL＇超级电容器，满足汽车和工业市场需求

在针对由Globalpress组织的亚洲媒体团（Asiapress Electronics）新闻发布会上，Maxwell Technologies公司（以下简称‘Maxwell公司’）发布功率型版本（Power-type versions）的BOOSTCAP “D—Cell”超级电容器单元（cells），组件（packs）以及模块（modules），这种高性能，并可维持整个系统寿命周期的产品主要是用来取代稳定汽车电力系统和工业应用领域的电池组等。全新的超级电容器BCAP0310 P250只有手电筒电池大小，具有310F的单元容量，是一种小巧、完全集成的解决方案，6单元15V组件和模块则提供了简单易用和低成本的电力备份解决方案（backup power solutions），这种系统方案可以解决由于汽车中多个同时启动的电力系统可能造成的系统故障，     

超级电容器研究进展

随着人们对于储能要求的不断提高,超级电容器以其功率密度大、循环寿命长等优点引起人们的广泛关注,并且在近些年得到了飞速发展,它填补了传统静电容器(高功率密度、低能量密度)和化学电池(高能量密度、低功率密度)的空白。本文依据近年来超级电容器领域所发表的文献,从超级电容器基本原理入手,对包括电极材料、电解液、隔膜以及集流体在内的各个组成部分的研究现状进行了综述,讨论了对称型超级电容器、非对称型超级电容器、全固态超级电容器及柔性透明超级电容器等特殊结构超级电容器的研究成果,并作出简要展望。     

超级电容器应用介绍

通过对超级电容器的基本原理、特点和主要性能指标的介绍,分析了超级电容器的工作原理和超级电容器模组的设计原理,通过实例阐述了超级电容器在高功率脉冲和瞬时功率保持两方面的应用。     

超级电容器动态等效模型研究

以超级电容器数学模型为研究对象,考虑超级电容器的充放电特性,对其等效模型进行研究,提出一种基于超级电容器充放电特性的动态等效电路模型。在该模型中,超级电容器的等效串并联内阻随电容器两端电压和电流动态变化。通过对比超级电容器进行充放电实验数据,结果表明该模型预测的充放电电压与实验值吻合。     

一种超级电容器充放电测试方法的研究

超级电容器较传统电容器而言有非常大的容量,但是其表现出显著的"非传导性吸收"储能方式,用传统的方法将不能准确地对超级电容器进行测试。针对超级电容器的工作原理,提出一种有针对性的超级电容器测试的方法。采用Buck变化器实现超级电容器的恒流充电,采用Boost变化器模拟有源电子负载实现超级电容器恒流放电,利用芯片SG3525产生PWM控制波形,实现恒流充放电,利用DSP(TMS3210C2812)完成系统数据处理。该方法保证了放大精度,有效抑制了共模噪声,对超级电容器在不同充放电电流下的电容与内阻工作情况实现了准确、有效的测试。     

Fast start crystal oscillator design with negative resistance control

Clock is an essential part of most of the integrated circuits as time base reference. It must be very accurate, highly reliable and readily available as soon as it is enabled. In all types of oscillator architectures, crystal oscillator is the most accurate and stable clock generator. But usually the crystal oscillator circuit suffers from slow startup. Therefore, it is essential to improve the startup time with optimally controlled crystal drive such that crystal drive power rating is not compromised. We propose a method that discusses about increasing the negative resistance during startup, using a startup circuit for fast start. Once the reliable startup is achieved, the negative resistance is decreased and the startup circuit is disconnected. The reduction in negative resistance is done with current steps and there are two ways in which it is achieved, the Digital control method and Analog control method. In digital control method, the current steps are timed at regular intervals and in analog control method, oscillator output amplitude is given as feedback to the startup circuit there by reducing the negative resistance. In the 32768 Hz real time clock generating oscillator, the startup time can be improved from 330 ms to 220 ms using the conventional startup method. With the proposed digital control method, lesser startup time of 160 ms is achieved and in analog control method it is further reduced to 120 ms.     

基于RBF神经网络的光纤陀螺启动补偿及应用

光纤陀螺对温度比较敏感,由于温度引起的零偏漂移是光纤陀螺工作尤其是启动过程中的一种较大误差。文中为了减小光纤陀螺启动过程的零偏漂移、缩短启动时间,提出了对光纤陀螺启动过程进行补偿的方案。该方案以光纤陀螺温度和温度变化率为输入、光纤陀螺漂移为输出建立二输入单输出的RBF神经网络,用于陀螺启动过程补偿。在室温下对某型号光纤陀螺启动漂移进行了补偿,试验结果表明该方法能有效减小陀螺的启动温度漂移,缩短陀螺启动时间。将该方案运用到某型号的光纤陀螺寻北仪上,常温试验表明,该方案大大缩短了寻北仪的准备时间,提高了寻北精度。     

基于AT91SAM9263的嵌入式系统启动过程分析

以Atmel公司的AT91SAM9263为例分析研究了它的bootloader启动过程.对从系统上电后的第一条指令到加载Linux kernel的过程进行了分析,主要阐述了bootstrap和uboot的启动过程.掌握嵌入式开发的启动过程,对后续的开发至关重要.     

具有电压检测功能的大功率设备软启动器设计

基于限制大功率设备启动时冲击电流的幅值、完善软启动器的各种功能、提高工作可靠性等目的,本轮文设计的软启动器利用运算放大器构成电压比较、运行自锁、延时等环节,通过采样整流滤波电容端电压的变化,实现交流输入电压检测、软启动电流切换、内部逻辑控制等功能,在不同的输入电压范围内,也能限制跃变电压的幅值,保证了软启动器工作的可靠性。该软启动器具有结构简单、动作可靠等优点,可广泛应用于电源输入端需进行AC/DC变换的大功率设备。     

Marketing, R&D, and Startup Valuation

The problem focus is on startup decisions associated with staged venture financing, where both R&D and marketing are significant percentages of overall expenses. When should a startup owner acquire working capital, and how should she/he distribute that capital between R&D (to improve product quality) and marketing (to increase sales) to ultimately grow valuation? Also, should the startup owner cap the total R&D and marketing budgets to increase profitability during staged venture financing? We develop a model to study resource acquisition and allocation decisions across successive stages of startup growth. The model incorporates a funding process whereby the startup valuation is positively impacted by improved product quality and market growth. This model provides insights on optimal acquisition and allocation practices and characterizes the impact of changes in productivity, along with the evolution rate of R&D and marketing payoffs, on the underlying decisions. Our results also illustrate conditions for optimal capping of R&D and marketing expenses as a percentage of revenues.     

变压器耦合LC正弦波振荡器的分析

在高频电子线路的教学中,变压器耦合反馈振荡器是LC正弦波振荡器中的重要内容。本文以常用的瞬时极性法分析了变压器耦合振荡电路的相位起振条件,以环路增益T的形式推导了振荡器的振幅起振条件,从而清晰地阐述了振荡器的工作原理,振幅起振条件及振荡频率与电路中各参数的关系。     

Windows CE下GPS导航设备的启动速度的优化

基于Windows CE的GPS导航设备,由于系统的采用的FAT文件系统自身的缺陷,导致启动速度缓慢.经过深入分析Nand Flash驱动程序,FAT文件系统以及导航地图数据的特点,提出了一种优化导航设备启动速度的方法,该方法分为两个步骤,第一步将地图文件转换为可下载的bin文件格式; 第二步通过EBOOT下载该bin文件.目前该方法已经应用到导航设备中,实测表明,该方法可以显著的提高导航设备的启动速度.     

感应电动机智能软启动器研究

为了解决三相异步电动机起动电流较大的问题,采用了一种软起动模糊自适应控制器。据其起动特性,将电流误差和误差的变化率作为输入量,晶闸管的控制角作为输出量,设计出一种自调整比例因子的模糊自适应控制算法。随后做了Matlab环境下的仿真实验,并且与常规的PID控制方法和常规模糊控制方法进行比较,得到了模糊自适应控制算法具有优越性的结论。     

Where should ICT startup companies be established? Efficiency comparison between cluster types

According to the triple helix model, the government, private companies, and universities play an important role in the development of the regional economy and the growth of clusters. Although balanced interaction with the three players is important in the triple helix model, our study points out that these three players have no choice but to compete. In this study, we conducted meta-frontier analysis (MFA) using three groups, the government, private companies, and universities, which are mentioned in the triple helix model to compare the efficiency of information and communication technology (ICT) startup companies. Therefore, we can see which ICT startup companies have grown up. As a result, the government-led cluster is the most efficient, followed by private company-led cluster and finally university-led cluster. Here, we compared all the clusters of ICT startup companies, unlike previous studies which only focused on a few clusters. Also, we provided another implication that the strengths of startup companies in each cluster can change depending on their geographic location.     

Simple starting scheme for a parallel resonance inverter forinduction heating

A starting scheme for thyristor-based parallel resonant current source inverters, with particular reference to induction heating applications, is presented. The input stage to the DC-link is a three-phase phase controlled rectifier. It is shown that instead of using the usual startup circuits providing forced commutation, it is possible to start the system by using a single additional thyristor across the DC-link inductor, together with a special timed gating at the input and output converter. The scheme provides startup for a wide range of loads. The paper explains the principle starting concept and derives a simplified model to quantify the important parameters that govern the startup. The theoretical concept is verified by experimental data demonstrating the start of such an inverter