外文翻譯---單級單刀功率因數(shù)校正器acdc變換器-其他專業(yè)-文庫吧資料
2025-01-27 09:23本頁面
【正文】 y regulated output approach can obtain very good performance, such ashigh power factor, and low voltage stress. However, due tothe use of two powerprocessing stages, conversionefficiency is reduced and an additional PFC stage addsponents and plexity. Consequently the overall costincreases. The twostage approach has disadvantages oflowpower density, control plexity, and high reduce the overall size and cost, a number of siglestagePFC converters have been developed in the literature witches so that the PFC switch anditscontroller can be eliminated. Thesinglestage approach is specially attractive in lowcost and lowpower applicationsdue to its simple power stage and control circuit. However,it still has several drawbacks such as high current stress inpower switch and high DCbus voltage stress. Its majordrawback is a high voltage stress on the DCbus singlestage PFC AC/DC converters suffer from highDCbus voltage stress at light load and high line, whichmakes these converters impractical. A high DCbusvoltage means high ponent rating, high cost and lowvoltage stress. Experimental results for a 60W converter ata constant switching frequency of 70 kHz are obtained toshow the performance of the proposed converter. It is hown that the voltage across the DCbus capacitor can beheld below 404V even though the converter operates in awide range of input voltages (90V265VAC) and themeasured input current harmonics satisfy the IEC 6100032Class D requirements. 2 Analysis of proposed converter Figure 1 shows the equivalent circuits of the proposedconverter. The secondary winding Nb is added in the PFC boost inductor. The first transformer T1 in DC/DC part can be operated either in CCM or DCM depending on the load conditions as in the conventional flyback converter. For simplification, DC/DC part is assumed to operate in CCM for entire line period. The second transformer T2 is operated in DCM. According to the operation of T2, When the DCbus voltage feedback value V1(=np2Vab, np2=N2/Np) is higher than the rectified line input voltage vi, the converter operation enters region A. In region A only T1 is operating and Db is reversebiased during the ontime period S. When Vi is higher than V1 and lower 咸寧學(xué)院本科畢業(yè)論文：外文翻譯 2 than V2 the operation converter enters region B. In this region T1 and T2 work like flyback transformers。 電子與信息工程學(xué)院 本科畢業(yè)論文 (設(shè)計 ) 外 文 文 獻(xiàn) 翻 譯 譯文題目： singlestage singleswitch powerfacter correction AC/DC converter 學(xué)生姓名： 專 業(yè)： 指導(dǎo)教師： 2021 年 3 月 原文 : 咸寧學(xué)院本科畢業(yè)論文：外文翻譯 1 Singlestage singleswitch power factor correctionAC/DC converter Abstract A singlestage singleswitch power factor correction AC/DC converter is proposed in which the power factor correction (PFC) inductor is connedted to a tap on the primary winding ofthe DC/DC flyback converter stage。 there is direct energy transfer of a part of the input energy tothe output and theDCbus voltage fee
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