开关电源毕业论文外文翻译

1、中英文翻译 本科毕业设计（论文） 中英文翻译学院名称： 电气信息工程学院 专 业： 电气工程及其自动化 班 级： 学 号： 姓 名： 指导教师姓名： 指导教师职称： 二一四 年 六 月外文资料（原文）Modeling, Simulation, and Reduction of Conducted Electromagnetic Interference Due to a PWM Buck Type Switching Power Supply I A. Farhadi Abstract:Undesired generation of radiated or conducted energy i

2、n 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 i

3、ntroduced 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

4、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 elect

5、ronics . High speed switching causes weight and volume reduction of equipment, but some unwanted effects such as radio frequency interference appeared . Compliance with electromagnetic compatibility (EMC) regulations is necessary for producers to present their products to the markets. It is importan

6、t to take EMC aspects already in design phase . 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 . Different types of power electronics co

7、nverters 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 . Interference spectrum at the output of LISN is introduc

8、ed as the EMC evaluation criterion . National or international regulations are the references for the evaluation of equipment in point of view of EMC . II. SOURCE, PATH AND VICTIM OF EMI Undesired voltage or current is called interference and their cause is called interference source. In this paper

9、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,

10、 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

11、common mode . 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 . The interference source, path impedances, differential mode current and load impedance ar

12、e 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

13、the common mode interference source, common mode currents Icm1 and Icm2 and the related current paths. 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

14、 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 import

15、ant source of electromagnetic interference and have corrupting effects on the electric networks . 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 sens

16、itive 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

17、 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 . For different groups of consumers different classes of regulations could be complied. Class A for common consumers and class

18、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 conduct

19、ed 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 . IV. ELECTROMAGNETIC CONDUCTED INTERFERENCE MEASUREMENT A. L

20、ine 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 frequ

21、ency with the mentioned topology is presented in Fig. 7. LISN has stabilized impedance in the range of conducted EMI measurement . 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 co

22、mparison 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 connec

23、ted 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

24、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

25、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45。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78。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

26、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和常见的电缆或电线连接进行传导。在这项研究中只考虑传导发射设备，如电脑，接收器，放大器，工业控制器等。这些被干扰源辐射的设备被称为受害者。常见的元素，源头接线，布线为噪声以及干扰的传导提供了途径。电磁传导干扰有差模和共模两种干扰方法9。A.差模传导干扰这种模式就是将一个噪声源的噪声施加到一个测试电路的不同线路。它的电路如下图1所示9。在图1中也显示了干扰源，路径阻抗，差模电流以及负载阻抗。图1差模传导干扰路径B.常见的干扰方式共模噪声或干扰可能出现在电线或者电缆的连接点。负载和接地点的任意泄露都可以被认为是电压干扰源。图2演示了共模干扰源在共模电流为Icm1和Icm2时相关的电流路径9。电力电子转换器可以被用来作为供应网络线路之间的噪音源。在这项研究中不同的传导干扰模式是非常重要的，所以讨论只会在这种模式下被继续考虑。三、电磁兼容性规章电子设备的应用，特别是那些拥有静态电力电子转换器的电子设备越来越多。就像前面讲的一样，电力电子转换器被视为一个重要的电磁干扰源，并能使电网产生腐坏。各种各样的干扰造成的高污染降低了电网电能的质量。另一方面，一些住宅，广告，特别是医疗器件对电力系统的电压及频率变化的干扰非常敏感。最好的解决干扰和提高电能质量的方法就是遵守国家或国际电磁兼容性规定。国际无线电干扰特别