反激式开关电源设计-毕设论文.doc

ABSTRACT摘要PAGEIⅢ摘要反激式开关电源因其结构简单，成本低被广泛应用。本文介绍了反激式开关电源的工作原理，比较了电流控制，电压控制和V2控制三种控制模式，重点阐述了电流控制模式的原理和优点。介绍了UC3843的特点，并基于该芯片从数学上建立稳态模型，得到有力的理论依据，为高频变压器和其它电路设计提供了技术参数。最后在硬件实现了一个有很好电压调整率，负载调整率，纹波小的反激式开关电源。关键词：反激式开关电源，UC3843，高频变压器，纹波ABSTRACTForsimplecircuitandlowcost,flybackswitchingpowersupplyiswidelyused.Thispaperintroducetheintroducestheworkingprincipleofcurrent-modeflybackswitchingpowersupply,madeaComparisonofseveralregularcontrollingmethodsofit．Basedonthecomparisonbetweenthedifferentmode，itemphasizestheworkingprincipleandadvantagesofthecurrent—modeswitchingpowersupply.AndthenintroducetheinternalstructureandworkingprincipalofUC3843．Basedonit,astablemathematicalmodeofcurrentwasbuilt.Itprovidestheevidencetodesign，analyse，andcalculatethestabilityanddynamiccharacteristicofthefollowingcircuit.Atlast,producedaflybackswitchingpowersupplywithgoodvoltageregulation,loadregulation,smallripplewasproduced.Keyword:flybackswitchingpowersupply,UC3843,highfrequencytransformer,rippPAGEIⅢ目录TOC\o"1-3"\h\z\uHYPERLINK\l"_Toc263270671"第1章绪论PAGEREF_Toc263270671\h1HYPERLINK\l"_Toc263270672"1.1开关电源概述PAGEREF_Toc263270672\h1HYPERLINK\l"_Toc263270673"1.1.1开关电源发展历史PAGEREF_Toc263270673\h1HYPERLINK\l"_Toc263270674"1.1.2开关电源分类PAGEREF_Toc263270674\h3HYPERLINK\l"_Toc263270675"1.1.3开关电源的发展趋势PAGEREF_Toc263270675\h7HYPERLINK\l"_Toc263270676"1.2本课题选题的依据和现实意义PAGEREF_Toc263270676\h8HYPERLINK\l"_Toc263270677"1.2.1选题来源PAGEREF_Toc263270677\h8HYPERLINK\l"_Toc263270678"1.2.2选题的意义PAGEREF_Toc263270678\h9HYPERLINK\l"_Toc263270679"1.3本文的主要内容及工作PAGEREF_Toc263270679\h10HYPERLINK\l"_Toc263270680"1.3.1课题内容PAGEREF_Toc263270680\h10HYPERLINK\l"_Toc263270681"1.3.2课题拟解决的主要问题PAGEREF_Toc263270681\h10HYPERLINK\l"_Toc263270682"1.3.3课题的创新点与难点PAGEREF_Toc263270682\h10HYPERLINK\l"_Toc263270683"第2章电流型反激式开关电源的工作原理PAGEREF_Toc263270683\h12HYPERLINK\l"_Toc263270684"2.1引言PAGEREF_Toc263270684\h12HYPERLINK\l"_Toc263270685"2.2电流型开关电源的结构框图及工作原