电磁干扰开关电源论文中英文对照资料外文翻译文献

电磁干扰开关电源论文中英文对照资料外文翻译文献
电磁干扰开关电源论文中英文对照资料外文翻译文献

中英文对照资料外文翻译文献

外文资料(原文)

Modeling, Simulation, and Reduction of Conducted Electromagnetic Interference Due to a PWM Buck Type Switching Power Supply I

Abstract:Undesired generation of radiated or conducted energy in electrical systems is called Electromagnetic Interference (EMI). High speed switching frequency in power electronics converters especially in switching power supplies improves efficiency but leads to EMI. Different kind of conducted interference, EMI regulations and conducted EMI measurement are introduced in this paper. Compliancy with national or international regulation is called Electromagnetic Compatibility (EMC). Power electronic systems producers must regard EMC. Modeling and simulation is the first step of EMC evaluation. EMI simulation results due to a PWM Buck type switching power supply are presented in this paper. To improve EMC, some techniques are introduced and their effectiveness

proved by simulation.

Index Terms:Conducted, EMC, EMI, LISN, Switching Supply

I. INTRODUCTION

FAST semiconductors make it possible to have high speed and high frequency switching in power electronics []1. High speed switching causes weight and volume reduction of equipment, but some unwanted effects such as radio frequency interference appeared []2. Compliance with electromagnetic compatibility (EMC) regulations is necessary for producers to present their products to the markets. It is important to take EMC aspects already in design phase []3. Modeling and simulation is the most effective tool to analyze EMC consideration before developing the products. A lot of the previous studies concerned the low frequency analysis of power electronics components []4[]5. Different types of power electronics converters are capable to be considered as source of EMI. They could propagate the EMI in both radiated and conducted forms. Line Impedance Stabilization Network (LISN) is required for measurement and calculation of conducted interference level []6. Interference spectrum at the output of LISN is introduced as the EMC evaluation criterion []7[]8. National or international regulations are the references for the evaluation of equipment in point of view of EMC []7[]8. II. SOURCE, PATH AND VICTIM OF EMI

Undesired voltage or current is called interference and their cause is

called interference source. In this paper a high-speed switching power supply is the source of interference.

Interference propagated by radiation in area around of an interference source or by conduction through common cabling or wiring connections. In this study conducted emission is considered only. Equipment such as computers, receivers, amplifiers, industrial controllers, etc that are exposed to interference corruption are called victims. The common connections of elements, source lines and cabling provide paths for conducted noise or interference. Electromagnetic conducted interference has two components as differential mode and common mode []9.

A. Differential mode conducted interference

This mode is related to the noise that is imposed between different lines of a test circuit by a noise source. Related current path is shown in

Fig. 1 []9. The interference source, path impedances, differential mode current and load impedance are also shown in Fig. 1.

B. Common mode conducted interference

Common mode noise or interference could appear and impose between the lines, cables or connections and common ground. Any leakage current between load and common ground could be modeled by interference voltage source.

Fig. 2 demonstrates the common mode interference source, common

mode currents I

cm1 and I

cm2

and the related current paths[]9.The power

electronics converters perform as noise source between lines of the supply network. In this study differential mode of conducted interference is particularly important and discussion will be continued considering this mode only.

III. ELECTROMAGNETIC COMPATIBILITY

REGULATIONS

Application of electrical equipment especially static power electronic converters in different equipment is increasing more and more. As mentioned before, power electronics converters are considered as an important source of electromagnetic interference and have corrupting effects on the electric networks []2. High level of pollution resulting from various disturbances reduces the quality of power in electric networks. On the other side some residential, commercial and especially medical consumers are so sensitive to power system disturbances including voltage and frequency variations. The best solution to reduce corruption and improve power quality is complying national or international EMC regulations. CISPR, IEC, FCC and VDE are among the most famous organizations from Europe, USA and Germany who are responsible for determining and publishing the most important EMC regulations. IEC and VDE requirement and limitations on conducted emission are shown in Fig. 3 and Fig. 4 []7[]9.

For different groups of consumers different classes of regulations could be complied. Class A for common consumers and class B with more hard limitations for special consumers are separated in Fig. 3 and Fig. 4. Frequency range of limitation is different for IEC and VDE that are 150 kHz up to 30 MHz and 10 kHz up to 30 MHz respectively. Compliance of regulations is evaluated by comparison of measured or

calculated conducted interference level in the mentioned frequency range with the stated requirements in regulations. In united European community compliance of regulation is mandatory and products must have certified label to show covering of requirements []8.

IV. ELECTROMAGNETIC CONDUCTED INTERFERENCE MEASUREMENT

A. Line Impedance Stabilization Network (LISN)

1-Providing a low impedance path to transfer power from source to power electronics converter and load.

2-Providing a low impedance path from interference source, here power electronics converter, to measurement port.

Variation of LISN impedance versus frequency with the mentioned

topology is presented in Fig. 7. LISN has stabilized impedance in the range of conducted EMI measurement []7.

Variation of level of signal at the output of LISN versus frequency is the spectrum of interference. The electromagnetic compatibility of a system can be evaluated by comparison of its interference spectrum with the standard limitations. The level of signal at the output of LISN in frequency range 10 kHz up to 30 MHz or 150 kHz up to 30 MHz is criterion of compatibility and should be under the standard limitations. In practical situations, the LISN output is connected to a spectrum analyzer and interference measurement is carried out. But for modeling and simulation purposes, the LISN output spectrum is calculated using appropriate software.

外文资料(译文)

基于压降型PWM开关电源的建模、仿真和减少传导性电磁干扰

摘要:电子设备之中杂乱的辐射或者能量叫做电磁干扰(EMI)。尤其是在开关电源中的电力电子转换器经常高速切换时,虽然提高了工作效率,却导致转换器产生了电磁干扰。在这篇论文之中介绍了各种各样的传导干扰,电磁干扰规章以及传导性电磁干扰的测量。如果电子设备的电磁干扰符合国家或者国际规章称为电磁兼容性(EMC)。电力电子系统生产商一定要重视电子设备的电磁兼容性。电磁兼容性评估的第一步就是建模和仿真。在这篇论文中提出了基于压降型脉宽调制开关电源的电磁干扰仿真结果。为了提高电子设备的电磁兼容性,在论文中介绍了一些技术,并且通过仿真提高了电子设备的工作效率。

关键字:传导,电磁兼容性,电磁干扰,线路阻抗稳定网络,开关电源一.前言

在电力电子领域中,快速半导体的出现使高速度,高频率的开关切换成为了可能[1]。高速的开关造成设备的重量和体积的减少,但与此同时这也造成了一些不利的影响,比如无线频率的干扰[2]。生产商将生产的产品投放到市场,遵守电磁兼容性规章是必要的。在设计阶段考虑电磁兼容性问题是非常重要的[3]。在开发产品前,建模和仿真是分析电磁兼容性最有效的工具。许多以前的研究都有涉及到电力电子元件的低频分析[4~5]。不同类型的电力电子转换器都能够被用来当做电磁的干扰源。电磁干扰源可以通过辐射和传导两种方式来传播。线路阻抗稳定网络被用来测量和计算电磁干扰影响的程度[6]。线路阻抗稳定网络输出的干扰频谱被引为电磁兼容性的评估标准[7,~8]。国家或国际规章是电子设备电磁兼容性评估的一个参考的方面[7~8]。

二、来源,途径和电磁干扰的受害者

杂乱的电压或者电流被称为干扰,而它们的来源被称为干扰源。本论文中的干扰源就是一个高速的开关电源。干扰通过辐射的方式在干扰源周围传播或通过

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外文翻译 专业机械设计制造及其自动化学生姓名刘链柱 班级机制111 学号1110101102 指导教师葛友华

外文资料名称: Design and performance evaluation of vacuum cleaners using cyclone technology 外文资料出处:Korean J. Chem. Eng., 23(6), (用外文写) 925-930 (2006) 附件: 1.外文资料翻译译文 2.外文原文

应用旋风技术真空吸尘器的设计和性能介绍 吉尔泰金,洪城铱昌,宰瑾李, 刘链柱译 摘要:旋风型分离器技术用于真空吸尘器 - 轴向进流旋风和切向进气道流旋风有效地收集粉尘和降低压力降已被实验研究。优化设计等因素作为集尘效率,压降,并切成尺寸被粒度对应于分级收集的50%的效率进行了研究。颗粒切成大小降低入口面积,体直径,减小涡取景器直径的旋风。切向入口的双流量气旋具有良好的性能考虑的350毫米汞柱的低压降和为1.5μm的质量中位直径在1米3的流量的截止尺寸。一使用切向入口的双流量旋风吸尘器示出了势是一种有效的方法,用于收集在家庭中产生的粉尘。 摘要及关键词:吸尘器; 粉尘; 旋风分离器 引言 我们这个时代的很大一部分都花在了房子,工作场所,或其他建筑,因此,室内空间应该是既舒适情绪和卫生。但室内空气中含有超过室外空气因气密性的二次污染物,毒物,食品气味。这是通过使用产生在建筑中的新材料和设备。真空吸尘器为代表的家电去除有害物质从地板到地毯所用的商用真空吸尘器房子由纸过滤,预过滤器和排气过滤器通过洁净的空气排放到大气中。虽然真空吸尘器是方便在使用中,吸入压力下降说唱空转成比例地清洗的时间,以及纸过滤器也应定期更换,由于压力下降,气味和细菌通过纸过滤器内的残留粉尘。 图1示出了大气气溶胶的粒度分布通常是双峰形,在粗颗粒(>2.0微米)模式为主要的外部来源,如风吹尘,海盐喷雾,火山,从工厂直接排放和车辆废气排放,以及那些在细颗粒模式包括燃烧或光化学反应。表1显示模式,典型的大气航空的直径和质量浓度溶胶被许多研究者测量。精细模式在0.18?0.36 在5.7到25微米尺寸范围微米尺寸范围。质量浓度为2?205微克,可直接在大气气溶胶和 3.85至36.3μg/m3柴油气溶胶。

基于单片机的开关电源外文参考文献译文及原文

本科毕业设计(论文) 外文参考文献译文及原文 学院信息工程学院 专业信息工程 年级班别 学号 学生姓名 指导教师

目录 译文 (1) 基于单片机的开关电源 (1) 1、用途 (1) 2、简介 (1) 3、分类 (2) 4、开关电源的分类 (3) 5、技术发展动向 (4) 6、原理简介 (6) 7、电路原理 (7) 8、DC/DC变换 (8) 9、AC/DC变换 (8) 原文 (10) The design Based onsingle chip switching power supply (10) 1、uses (10) 2、Introduction (10) 3、classification (11) 4、the switching power supply. (13) 5、technology developments (14) 6、the principle of Introduction (17) 7、the circuit schematic (18) 8、the DC / DC conversion (19) 9, AC / DC conversion (20)

译文 基于单片机的开关电源 1、用途 开关电源产品广泛应用于工业自动化控制、军工设备、科研设备、LED 照明、工控设备、通讯设备、电力设备、仪器仪表、医疗设备、半导体制冷制热、空气净化器,电子冰箱,液晶显示器,LED灯具,通讯设备,视听产品,安防,电脑机箱,数码产品和仪器类等领域。 2、简介 随着电力电子技术的高速发展,电力电子设备与人们的工作、生活的关系日益密切,而电子设备都离不开可靠的电源,进入80年代计算机电源全面实现了开关电源化,率先完成计算机的电源换代,进入90年代开关电源相继进入各种电子、电器设备领域,程控交换机、通讯、电子检测设备电源、控制设备电源等都已广泛地使用了开关电源,更促进了开关电源技术的迅速发展。 开关电源是利用现代电力电子技术,控制开关晶体管开通和关断的时间比率,维持稳定输出电压的一种电源,开关电源一般由脉冲宽度调制(PWM)控制IC和开关器件(MOSFET、BJT等)构成。开关电源和线性电源相比,二者的成本都随着输出功率的增加而增长,但二者增长速率各异。线性电源成本在某一输出功率点上,反而高于开关电源。随着电力电子技术的发展和创新,使得开关电源技术在不断地创新,这一成本反转点日益向低输出电力端移动,这为开关电源提供了广泛的发展空间。 开关电源高频化是其发展的方向,高频化使开关电源小型化,并使开关电源进入更广泛的应用领域,特别是在高新技术领域的应用,推动了高新技术产品的小型化、轻便化。另外开关电源的发展与应用在节约能源、节约资源及保护环境方面都具有重要的意义。

毕业论文 外文翻译#(精选.)

毕业论文(设计)外文翻译 题目:中国上市公司偏好股权融资:非制度性因素 系部名称:经济管理系专业班级:会计082班 学生姓名:任民学号: 200880444228 指导教师:冯银波教师职称:讲师 年月日

译文: 中国上市公司偏好股权融资:非制度性因素 国际商业管理杂志 2009.10 摘要:本文把重点集中于中国上市公司的融资活动,运用西方融资理论,从非制度性因素方面,如融资成本、企业资产类型和质量、盈利能力、行业因素、股权结构因素、财务管理水平和社会文化,分析了中国上市公司倾向于股权融资的原因,并得出结论,股权融资偏好是上市公司根据中国融资环境的一种合理的选择。最后,针对公司的股权融资偏好提出了一些简明的建议。 关键词:股权融资,非制度性因素,融资成本 一、前言 中国上市公司偏好于股权融资,根据中国证券报的数据显示,1997年上市公司在资本市场的融资金额为95.87亿美元,其中股票融资的比例是72.5%,,在1998年和1999年比例分别为72.6%和72.3%,另一方面,债券融资的比例分别是17.8%,24.9%和25.1%。在这三年,股票融资的比例,在比中国发达的资本市场中却在下跌。以美国为例,当美国企业需要的资金在资本市场上,于股权融资相比他们宁愿选择债券融资。统计数据显示,从1970年到1985年,美日企业债券融资占了境外融资的91.7%,比股权融资高很多。阎达五等发现,大约中国3/4的上市公司偏好于股权融资。许多研究的学者认为,上市公司按以下顺序进行外部融资:第一个是股票基金,第二个是可转换债券,三是短期债务,最后一个是长期负债。许多研究人员通常分析我国上市公司偏好股权是由于我们国家的经济改革所带来的制度性因素。他们认为,上市公司的融资活动违背了西方古典融资理论只是因为那些制度性原因。例如,优序融资理论认为,当企业需要资金时,他们首先应该转向内部资金(折旧和留存收益),然后再进行债权融资,最后的选择是股票融资。在这篇文章中,笔者认为,这是因为具体的金融环境激活了企业的这种偏好,并结合了非制度性因素和西方金融理论,尝试解释股权融资偏好的原因。

毕业设计外文翻译

毕业设计(论文) 外文翻译 题目西安市水源工程中的 水电站设计 专业水利水电工程 班级 学生 指导教师 2016年

研究钢弧形闸门的动态稳定性 牛志国 河海大学水利水电工程学院,中国南京,邮编210098 nzg_197901@https://www.360docs.net/doc/a59927178.html,,niuzhiguo@https://www.360docs.net/doc/a59927178.html, 李同春 河海大学水利水电工程学院,中国南京,邮编210098 ltchhu@https://www.360docs.net/doc/a59927178.html, 摘要 由于钢弧形闸门的结构特征和弹力,调查对参数共振的弧形闸门的臂一直是研究领域的热点话题弧形弧形闸门的动力稳定性。在这个论文中,简化空间框架作为分析模型,根据弹性体薄壁结构的扰动方程和梁单元模型和薄壁结构的梁单元模型,动态不稳定区域的弧形闸门可以通过有限元的方法,应用有限元的方法计算动态不稳定性的主要区域的弧形弧形闸门工作。此外,结合物理和数值模型,对识别新方法的参数共振钢弧形闸门提出了调查,本文不仅是重要的改进弧形闸门的参数振动的计算方法,但也为进一步研究弧形弧形闸门结构的动态稳定性打下了坚实的基础。 简介 低举升力,没有门槽,好流型,和操作方便等优点,使钢弧形闸门已经广泛应用于水工建筑物。弧形闸门的结构特点是液压完全作用于弧形闸门,通过门叶和主大梁,所以弧形闸门臂是主要的组件确保弧形闸门安全操作。如果周期性轴向载荷作用于手臂,手臂的不稳定是在一定条件下可能发生。调查指出:在弧形闸门的20次事故中,除了极特殊的破坏情况下,弧形闸门的破坏的原因是弧形闸门臂的不稳定;此外,明显的动态作用下发生破坏。例如:张山闸,位于中国的江苏省,包括36个弧形闸门。当一个弧形闸门打开放水时,门被破坏了,而其他弧形闸门则关闭,受到静态静水压力仍然是一样的,很明显,一个动态的加载是造成的弧形闸门破坏一个主要因素。因此弧形闸门臂的动态不稳定是造成弧形闸门(特别是低水头的弧形闸门)破坏的主要原是毫无疑问。

开关电源 外文文献

开关电源 与电子技术的飞速发展,电子系统的应用领域越来越广泛,电子设备,有越来越多的人工作以电子设备、生活越来越密切的关系。任何电子设备都离不开可靠供电电源的需求,他们也越来越高。电子设备的小型化、低成本的光的力量又瘦,小而高效的为发展方向。传统的晶体管稳压电源是系列调整连续控制线性稳压电源。这种传统的稳压电源的技术更加成熟,已经有大量的综合线性稳压电源模块,有稳定的性能好、输出电压波动小、运行可靠等。但通常需要体积大且沉重的工频变压器和体积和重量是大的过滤器。 在1950年代,美国国家航空和宇宙航行局的小型化、轻重量为目标,为火箭携带开关电源的发展。在近半个世纪的发展过程中,开关电源因其体积小、重量轻、效率高,适用范围广,电压的优点在电子、控制、计算机等许多领域的电子设备已得到广泛应用。在1980年代,计算机是由所有开关电源的,第一个完整的计算机发电。整个1990年代,开关电源在电子、电器、家用电器领域得到广泛、开关电源技术进入快速发展。此外,大规模集成电路技术,和快速发展,开关电源有了质的飞跃,提高了高频大功率产品的、小型化、模块化的潮流。 电源开关管、PWM控制器和高频变压器是不可或缺的组成部分,开关电源。传统的开关电源的一般均采用高频大功率开关管的划分及各销,如利用PWM(脉宽调制)集成控制器UC3842 + MOSFET是国内小功率开关电源的设计方法,更流行。 自1970年代以来,出现在许多功能完全集成控制电路、开关电源电路越来越简化,工作频率的不断提高,提高效率,为电力小型化提供更为广阔的发展前景。三结束离线脉冲宽度调制单片机顶部(三个交换线)将终端时,电源开关MOSFET PWM控制器包在一起,已经成为国际关系的主流,开关电源IC发展。采用集成电路设计上的开关电源开关,可使电路简单、体积进一步缩小,成本也明显降低 单片开关电源有单片集成,最简外围电路,最好的性能指标、没有工作频率变压器能构成一个重要的优势开关电源等PI(以)。美国公司在电力在1990年代中期,首次推出新高频开关电源芯片,被称为“上开关电源”的宗旨,以低成本、电路简单、效率较高。第一代产品于1994年代表TOP100/200系列,第二代产品是ⅡTOPSwitch - 1997年问世。以上产品一旦出现较强的生命力和他大大简化了 设计的150 W以下开关电源和新产品的开发为新工作,也、高效、低成本开关电源和普及推广创造了良好条件,可广泛用于仪表、笔记本电脑、移动电话、电视、VCD、DVD、摄录像机、手机电池充电器、功率放大器等领域,并形成各自不同小型化、密度、价格可以跟线性稳压电源AC / DC电源变换模块。 开关电源的综合了今后的发展方向将是主要趋势,功率密度将越来越大,对工艺的要求将越来越高。在半导体器件和磁性材料,没有新的突破性的技术进步主要之前可能很难达到、技术创新的重点将是如何提高工作效率和集中在减肥。因此,工艺水平将会在这个位置的电源生产更高。此外,应用数字控制电路是未来的方向发展的一个开关电源。在DSP这种信任在速度和抗干扰技术的不断提高。至于先进控制方法,目前个人觉得没见过的实用性方法显得尤为强烈, 也许是流行的数字控制,会有一些新的控制理论引入开关电源。 (1)技术:用高频开关频率增加、开关变换器体积也减少,功率密度也大幅提升,动态响应得到改善。小功率直流-直流转换器开关频率将上升到兆赫。但是当开关频率的不断提高,开关元件、被动元件损失增加、高频寄生参数和高频电磁干扰(EMI)等新问题也会造成。

开关电源 高频 变压器计算设计

要制造好高频变压器要注意两点: 一就是每个绕组要选用多股细铜线并在一同绕,不要选用单根粗铜线,简略地说便就是高频交流电只沿导线的表面走,而导线内部就是不走电流的实习就是越挨近导线中轴电流越弱,越挨近导线表面电流越强。选用多股细铜线并在一同绕,实习便就是为了增大导线的表面积,然后更有效地运用导线。 二就是高频逆变器中高频变压器最好选用分层、分段绕制法,这种绕法首要目的就是削减高频漏感与降低分布电容。 1、次级绕组:初级绕组绕完,要加绕(3~5层绝缘垫衬再绕制次级绕组。这样可减小初级绕组与次级绕组之间分布电容的电容量,也增大了初级与次级之间的绝缘强度,契合绝缘耐压的需求。减小变压器初级与次级之间的电容有利于减小开关电源输出端的共模打扰。若就是开关电源的次级有多路输出,而且输出之间就是不共地的为了减小漏感,让功率最大的次级接近变压器的初级绕组。 若就是这个次级绕组只要相对较少几匝,则为了改善耦合状况,仍就是应当设法将它布满完好的一层,如能够选用多根导线并联的方法,有助于改善次级绕组的填充系数。其她次级绕组严密的绕在这个次级绕组的上面。当开关电源多路输出选用共地技能时,处置方法简略一些。次级能够选用变压器抽头方式输出,次级绕组间不需要采用绝缘阻隔,从而使变压器的绕制愈加紧凑,变压器的磁耦合得到加强,能够改善轻载时的稳压功能。 2、初级绕组:初级绕组应放在最里层,这样可使变压器初级绕组每一匝用线长度最短,从而使整个绕组的用线为最少,这有效地减小了初级绕组自身的分布电容。通常状况下,变压器的初级绕组被规划成两层以下的绕组,可使变压器的漏感为最小。初级绕组放在最里边,使初级绕组得到其她绕组的屏蔽,有助于减小变压器初级绕组与附近器材之间电磁噪声的相互耦合。初级绕组放在最里边,使初级绕组的开始端作为衔接开关电源功率晶体管的漏极或集电极驱动端,可削减变压器初级对开关电源其她有些电磁打扰的耦合。 3、偏压绕组:偏压绕组绕在初级与次级之间,仍就是绕在最外层,与开关电源的调整就是依据次级电压仍就是初级电压进行有关。若就是电压调整就是依据次级来进行的则偏压绕组应放在初级与次级之间,这样有助于削减电源发生的传导打扰发射。若就是电压调整就是依据初级来进行的则偏压绕组应绕在变压器的最外层,这可使偏压绕组与次级绕组之间坚持最大的耦合,而与初级绕组之间的耦合减至最小。 初级偏压绕组最佳能布满完好的一层,若就是偏压绕组的匝数很少,则能够采用加粗偏压绕组的线径,或许用多根导线并联绕制,改善偏压绕组的填充状况。这一改善方法实际上也改善了选用次级电压来调理电源的屏蔽才干,相同也改善了选用初级电压来调理电源时,次级绕组对偏压绕组的耦合状况。高频变压器匝数如何计算?很多设计高频变压器的人都会有对于匝数的计算问题,那么我们应该如何来计算高频变压器的匝数,从而解决这个问题?接下来,晨飞电子就为大家介绍下匝数的计算方法: 开关电源高频变压器参数计算

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