计算机稳压电源和不间断电源

计算机稳压电源和不间断电源林碎德，王鹤龙我们知道，当电网电压值在计算机设备指定值的±１０％，即在１９８Ｖ—２６４Ｖ之间时，计算机系统方可正常运行。由于工厂、住宅区的用电不平衡、磁场干扰、同一供电系统中各用电设备间的相互干扰以及供电系统本身的各种原因，...     

电源噪声滤波器

一、概述随着电子设备、计算机和家用电器的推广普及,电网噪声干扰问题日益严重并形成公害,因为这种干扰可导致电子设备无法正常工作。电源噪声滤波器PNF(power noise filter)是国际80年代问世的一种新型器件。它可以广泛用于电子测量仪器、智能仪器、自动控制系统、计算机房设备等领域,能有效地抑制电源噪声,已成为提高设备抗干扰能力及系统可靠性的必备器件。目前,国内外竞相开发PNF,例如德国西门     

电源管理——及MOHO

一、电源管理应用无处不在 电源管理的应用无处不在，从计算机、便携设备、家电到工业控制、照明、宇航、军事等领域，市场极为广阔。随着各种整机设备市场规模的不断增长和社会对环保问题的日益重视，功耗问题逐渐成为关注热点，电源管理和电源控制IC市场成为整个半导体产业中最为活跃的领域之一，降低电子产品功耗这一需求，将推动电源管理器件市场的稳步发展。     

微机电源浅析

微型计算机作为一种特定的精密仪器,决定它对电源有特定的要求。微机系统主要是由集成块组成的主机、磁记录设备(软盘、硬盘)和键盘、显示器等外设构成。主机和记录设备的工作特性严格要求电源应是干净的、稳定的、无干扰的,否则将使数据丢失、磁盘损坏、甚至损坏机器。 而电网干扰普遍存在。据美国IBM公司的报告指出:美国在东海岸有113次/月严重干扰、15次/日电压波动,西海岸有128次/2月     

电磁兼容(150kHz～30MHz)传导干扰新测试方法的研究和应用

论文从电磁兼容150kHz～30MHz传导干扰项目中主要采样设备人工电源网络的原理结构图进行分析,提出一种新的测试方法,能够准确对大电流被测设备产生的传导干扰噪声进行采样,同时用实际产品数据进行验证.     

怎样选择不间断电源及线路保护器

一、引言 当计算机在现代社会中扮演的角色越来越重要的时候,其可靠稳定运行成为保障企业乃至社会正常运转的前提。而不间断电源或其他的电源保护设备进而成为前提的前提。 可怕的数据破坏者—电源停电或间断—是对计算机设备及其使用最大的威胁。但研究表明更可能使计算机遭到破坏的是电源的干扰,例如电压过低、毛刺、浪涌和电噪声等。罪魁祸首可能是大自然的原因,例如闪电,或者更可能是人为的因素,例如电网的负荷过重或错误的接线方式等。 电源干扰产生的后果可能是灾难性的—系统死机、文件冲突甚至损坏硬件。但在没有发生这些灾难     

基于PXA270的电源管理

电源管理是目前便携式设备需要解决的重要问题。Intel公司的PXA270芯片是在便携式设备中普遍使用的微处理器系统芯片。该文详细讲解了PXA270各种电源状态,以及时钟频率和电压的改变。     

请重视电源接线板

市电中潜在的过电压、过电流和各种干扰会通过电源插座危害和干扰电脑的正常运行，并且可能对操作人员、电脑设备造成伤害与损失看似不起眼的电源接线板，其实与电脑的安全、稳定运行息息相关。     

谁动了UPS的“奶酪”

中小功率UPS商机无限 随着网络系统的应用越来越广泛,有一种独立的电源设备,已发展成为整个计算机、网络系统中不可分割的一部分,这就是UPS。 所谓UPS(uninterruptible Power System),就是不间断电源,它是一种含有储能装置、以逆变器为主要组成部分的恒压恒频的电源设备。它是在1888年后,人们发明了照明电池,出现了直交互换的供电方式后诞生的。其主要功能是当市电输入正常时,会将电流稳压后供应给负载使用;当市电中断时,会及时向用电设备提供电能,使设备仍能持续工作一段时间,以便处理好未完成的工作。 由于各种原因导致网络服务中断而带来的损失往往是巨大的,而在各种原因中,因电力造成的损失无疑是很重要的一环。为了最大限度地减少这种损失,人们因此对电源     

商业自动化系统中的电源问题(上)

电源是所有商业自动化设备的基础,尤其对广泛使用于商业自动化领域的各种计算机系统,电源更是系统的关键部件.据统计,在计算机的故障中,有50%-70%的原因是电源故障造成的.在其他的商业自动化设备中,电源故障也是突出的问题.例如,商场安全技术防范系统中某些部件的损坏可能只是系统局部的失效,而电源故障的结果是整个系统的崩溃,甚至可能导致严重的后果.因此,商业自动化系统的电源问题应当引起有关人员的高度重视.     

Comparing system level power management policies

Reducing power consumption is a challenge to system designers. Portable systems, such as laptop computers and personal digital assistants (PDAs), draw power from batteries, so reducing power consumption extends their operating times. For desktop computers or servers, high power consumption raises temperature and deteriorates performance and reliability. Soaring energy prices and rising concern about the environmental impact of electronics systems further highlight the importance of low power consumption. Power reduction techniques can be classified as static and dynamic. Static techniques, such as synthesis and compilation for low power, are applied at design time. In contrast, dynamic techniques use runtime behavior to reduce power when systems are serving light workloads or are idle. These techniques are known as dynamic power management (DPM). DPM can be achieved in different ways; for example, dynamic voltage scaling (DVS) changes supply voltage at runtime as a method of power management. Here, we use DPM specifically for shutting down unused I/O devices. We built an experimental environment on a laptop computer running Microsoft Windows. We implemented existing power management policies and quantitatively compared their effects on power saving and performance degradation     

谐振式无线电能传输电源方案设计分析

在无线电能传输系统中,需要通过提高交流电源的频率来提高系统的传输效率。目前国内外对无线电能传输系统的研究都是直接将经典E类功率放大器或者逆变电路作为其高频电源,研究整个系统的传输特性,而对不同场合下如何选择高频电源没有系统分析。针对这一点,在结合几种高频电源以及开关器件的特点下,总结出无线电能传输系统在不同功率场合下的最佳电源选择。此外,提出将IGBT作为E类功率放大器的开关器件用于几百瓦左右的中等功率场合,以及将三相式E类功率放大器用于小功率的多负载输出场合。仿真分析了每种电源的特点和适用范围,为研究无线电能传输电源提供了系统的理论参考。     

Understanding statistical power in the context of applied research

Estimates of statistical power are widely used in applied research for purposes such as sample size calculations. This paper reviews the benefits of power and sample size estimation and considers several problems with the use of power calculations in applied research that result from misunderstandings or misapplications of statistical power. These problems include the use of retrospective power calculations and standardized measures of effect size. Methods of increasing the power of proposed research that do not involve merely increasing sample size (such as reduction in measurement error, increasing 'dose' of the independent variable and optimizing the design) are noted. It is concluded that applied researchers should consider a broader range of factors (other than sample size) that influence statistical power, and that the use of standardized measures of effect size should be avoided (except as intermediate stages in prospective power or sample size calculations).     

基于低阈值单元的高性能低功耗设计方法

在高性能IC设计中对高低两种阈值电压技术进行比较,利用低阈值电压降低动态功耗的手段实现降低总功耗的目标,并分析出了两种阈值电压低功耗设计各自适应的电路类型。首先对40nm工艺中标准单元的内部功耗、时序、尺寸进行分析。接着在相同延时下对高阈值和低阈值两种标准单元所设计的反相器链时序电路的功耗进行对比分析。最后基于Benchmark和AES两种类型电路,分别采用高阈值和低阈值进行综合,对比得出在相同时钟周期下更低功耗的设计所对应的阈值电压设计方式。结果显示,在相同的时钟频率下,对动态功耗占据总功耗比例极大的电路使用低阈值设计得到的功耗更低。同样,在动态功耗比例不是极大的电路中,当低阈值综合的slack为正时,以及当高阈值综合的slack为负、低阈值的slack为0时,用低阈值设计功耗更低;而当高阈值、低阈值综合的slack都为0时,用高阈值设计功耗更低。     

Do you know what your license allows?

Before you push a key to load a program and display it on your monitor, ask yourself this question: “Do I have the power to use this program?” Using software requires power-not physical or electrical power-but the legal power of authorized use. If you are not the program's author or owner, you can only obtain this power through a license-a legal document that states your rights regarding use of the program. This may include the right to use or operate the program as an end user; modify the program through deletions, additions or enhancements as a value-added reseller or original equipment manufacturer; or transfer the program to another as an aggregator, distributor or retailer. If you do not have the appropriate legal power, then your conduct is illegal. If you know that you do not have the appropriate legal power, then your conduct, which amounts to software piracy, is criminal     

Power geometric operators of trapezoidal intuitionistic fuzzy numbers and application to multi-attribute group decision making

As a special intuitionistic fuzzy set on a real number set, trapezoidal intuitionistic fuzzy numbers (TrIFNs) have the better capability to model ill-known quantities. The purpose of this paper is to develop some power geometric operators of TrIFNs and apply to multi-attribute group decision making (MAGDM) with TrIFNs. First, the lower and upper weighted possibility means of TrIFNs are introduced as well as weighted possibility means. Hereby, a new lexicographic method is developed to rank TrIFNs. The Minkowski distance between TrIFNs is defined. Then, four kinds of power geometric operators of TrIFNs are investigated including the power geometric operator of TrIFNs, power weighted geometric operator of TrIFNs, power ordered weighted geometric operator of TrIFNs and power hybrid geometric operator of TrIFNs. Their desirable properties are discussed. Four methods for MAGDM with TrIFNs are respectively proposed for the four cases whether the weight vectors of attributes and DMs are known or unknown. In these methods, the individual overall attribute values of alternatives are generated by using the power geometric or power weighted geometric operator of TrIFNs. The collective overall attribute values of alternatives are determined through constructing the multi-objective optimization model, which is transformed into the goal programming model to solve. Thus, the ranking order of alternatives is obtained according to the collective overall attribute values of alternatives. Finally, the green supplier selection problem is illustrated to demonstrate the application and validation of the proposed method.     

基于MSP430的光万用表设计与实现

针对国内市场上的光万用表多数与国外有较大的差距,或功耗过高或测量不够精确,而文献也多是研究独立的光功率计或红外光源系统的现状,设计了一款手持式光万用表系统。给出了关键模块的原理图、软件流程图以及数据处理算法,并对系统实现进行了较为详细的描述。该仪表以超低功耗微处理MSP430为控制核心,集成光功率计和红外光源模块,并具有USB通信接口。测试结果表明,其光功率计模块性能优异、功耗极低,其红外光源稳定,具有很高的使用价值。     

Modelling of the whole process of a university campus CHP power plant and dynamic performance study

Combined heat and power (CHP) refers to a process/system designed to utilize the waste or residual heat from a power generation process. Thus, a CHP plant can produce both electricity and heat. The nature of such a combination makes the process more complex than any single power generation process or boiler heating system. The paper focuses on modelling study and analysis of energy efficiency of the University of Warwick micro-CHP power plant. In this CHP modelling study, a gas turbine module is built to provide driving power and methane is used as fuel gas. Heat recovery system and auxiliary boiler modules are developed for thermal power generation. All the sub-systems are validated by comparing the simulation results with the operating data collected from the CHP plant. The dynamic performance of the key CHP process outputs is studied with respect to the variation of the input syngas stream, including electricity generation, thermal power output and water output temperature. Simplified controllers are also applied to the gas engineheat recovery subsystem and auxiliary boiler. Simulation results with/without feedback control are both analyzed. The study has highlighted the key factors which influence the plant performance and suggested the strategy for potential energy efficiency improvement.     

输电线路塔上设备供电方式分析

输电线路及杆塔上安装的用于监测、运维、通信等功能的设备需要稳定、持久、可靠的电能供应。文章通过分 析本地供电及远供电方式的优缺点及适用性,提出了适用于安装在输电线路及杆塔上的设备的几种供电方式：光伏供电,风机 供电,蓄电池供电,抽能取电,并创新地提出采用新型馈电OPGW进行随线馈电的供电方式。输电线路感应抽能及随线馈电 技术作为新型的在线取电的方式,与传统的供电方式相比可输出功率较大,但是其存在稳定性、对输电线路安全性的影响及经 济性等问题,建议进行更深入的研究。