開kai關guan電dian源yuan已yi經jing成cheng為wei了le我wo們men電dian路lu設she計ji當dang中zhong的de主zhu角jiao
，甚shen至zhi可ke以yi說shuo已yi經jing成cheng為wei了le與yu行xing業ye發fa展zhan密mi不bu可ke分fen的de一yi部bu分fen。與yu傳chuan統tong線xian性xing電dian源yuan相xiang比bi，在zai某mou一yi輸shu出chu功gong率lv點dian上shang線xian性xing電dian源yuan的de成cheng本ben要yao高gao於yu開kai關guan電dian源yuan，常chang見jian的de開kai關guan電dian源yuan可ke以yi分fen為wei兩liang種zhong，隔ge離li與yu非fei隔ge離li。

在(zai)本(ben)篇(pian)文(wen)章(zhang)當(dang)中(zhong)，我(wo)們(men)將(jiang)主(zhu)要(yao)對(dui)隔(ge)離(li)式(shi)開(kai)關(guan)電(dian)源(yuan)的(de)拓(tuo)撲(pu)形(xing)式(shi)進(jin)行(xing)探(tan)討(tao)。所(suo)以(yi)在(zai)下(xia)麵(mian)的(de)文(wen)章(zhang)當(dang)中(zhong)，如(ru)果(guo)沒(mei)有(you)任(ren)何(he)特(te)殊(shu)的(de)說(shuo)明(ming)
，文(wen)中(zhong)提(ti)及(ji)的(de)電(dian)源(yuan)將(jiang)均(jun)指(zhi)隔(ge)離(li)電(dian)源(yuan)。隔(ge)離(li)電(dian)源(yuan)按(an)照(zhao)結(jie)構(gou)形(xing)式(shi)不(bu)同(tong)
，可(ke)分(fen)為(wei)兩(liang)大(da)類(lei)：正激式和反激式。反激式指在變壓器原(yuan)邊(bian)導(dao)通(tong)時(shi)副(fu)邊(bian)截(jie)止(zhi)，變(bian)壓(ya)器(qi)儲(chu)能(neng)。原(yuan)邊(bian)截(jie)止(zhi)時(shi)
，副(fu)邊(bian)導(dao)通(tong)
，能(neng)量(liang)釋(shi)放(fang)到(dao)負(fu)載(zai)的(de)工(gong)作(zuo)狀(zhuang)態(tai)，一(yi)般(ban)常(chang)規(gui)反(fan)激(ji)式(shi)電(dian)源(yuan)單(dan)管(guan)多(duo)，雙(shuang)管(guan)的(de)不(bu)常(chang)見(jian)。正(zheng)激(ji)式(shi)指(zhi)在(zai)變(bian)壓(ya)器(qi)原(yuan)邊(bian)導(dao)通(tong)同(tong)時(shi)副(fu)邊(bian)感(gan)應(ying)出(chu)對(dui)應(ying)電(dian)壓(ya)輸(shu)出(chu)到(dao)負(fu)載(zai)，能(neng)量(liang)通(tong)過(guo)變(bian)壓(ya)器(qi)直(zhi)接(jie)傳(chuan)遞(di)。按(an)規(gui)格(ge)又(you)可(ke)分(fen)為(wei)常(chang)規(gui)正(zheng)激(ji)，包(bao)括(kuo)單(dan)管(guan)正(zheng)激(ji)

，雙(shuang)管(guan)正(zheng)激(ji)。半(ban)橋(qiao)、橋式電路都屬於正激電路。

正zheng激ji和he反fan激ji電dian路lu各ge有you其qi特te點dian
，在zai設she計ji電dian路lu的de過guo程cheng中zhong為wei達da到dao最zui優you性xing價jia比bi

，可ke以yi靈ling活huo運yun用yong。一yi般ban在zai小xiao功gong率lv場chang合he可ke選xuan用yong反fan激ji式shi。稍shao微wei大da一yi些xie可ke采cai用yong單dan管guan正zheng激ji電dian路lu
，中zhong等deng功gong率lv可ke采cai用yong雙shuang管guan正zheng激ji電dian路lu或huo半ban橋qiao電dian路lu，低di電dian壓ya時shi采cai用yong推tui挽wan電dian路lu，與yu半ban橋qiao工gong作zuo狀zhuang態tai相xiang同tong。大da功gong率lv輸shu出chu
，一yi般ban采cai用yong橋qiao式shi電dian路lu
，低di壓ya也ye可ke采cai用yong推tui挽wan電dian路lu。

反(fan)激(ji)式(shi)電(dian)源(yuan)因(yin)其(qi)結(jie)構(gou)簡(jian)單(dan)
，省(sheng)掉(diao)了(le)一(yi)個(ge)和(he)變(bian)壓(ya)器(qi)體(ti)積(ji)大(da)小(xiao)差(cha)不(bu)多(duo)的(de)電(dian)感(gan)，而(er)在(zai)中(zhong)小(xiao)功(gong)率(lv)電(dian)源(yuan)中(zhong)得(de)到(dao)廣(guang)泛(fan)的(de)應(ying)用(yong)。在(zai)有(you)些(xie)介(jie)紹(shao)中(zhong)講(jiang)到(dao)反(fan)激(ji)式(shi)電(dian)源(yuan)功(gong)率(lv)隻(zhi)能(neng)做(zuo)到(dao)幾(ji)十(shi)瓦(wa)，輸(shu)出(chu)功(gong)率(lv)超(chao)過(guo)100瓦就沒有優勢，實現起來有難度。本人認為一般情況下是這樣的
，但也不能一概而論
，PI公司的TOP芯片就可做到300瓦，有文章介紹反激電源可做到上千瓦，但沒見過實物。輸出功率大小與輸出電壓高低有關。

fanjidianyuanbianyaqilouganshiyigefeichangguanjiandecanshu，youyufanjidianyuanxuyaobianyaqichucunnengliang
，yaoshibianyaqitiexindedaochongfenliyong，yibandouyaozaiciluzhongkaiqixi
，qimudeshigaibiantiexincizhihuixiandexielv
，shibianyaqinenggouchengshoudademaichongdianliuchongji，erbuzhiyutiexinjinrubaohefeixianxingzhuangtai
，ciluzhongqixichuyugaocizuzhuangtai，zaiciluzhongchanshenglouciyuandayuwanquanbihecilu。

脈mai衝chong電dian壓ya連lian線xian盡jin可ke能neng短duan，其qi中zhong輸shu入ru開kai關guan管guan到dao變bian壓ya器qi連lian線xian
，輸shu出chu變bian壓ya器qi到dao整zheng流liu管guan連lian接jie線xian。脈mai衝chong電dian流liu環huan路lu盡jin可ke能neng小xiao如ru輸shu入ru濾lv波bo電dian容rong正zheng到dao變bian壓ya器qi到dao開kai關guan管guan返fan回hui電dian容rong負fu。輸shu出chu部bu分fen變bian壓ya器qi出chu端duan到dao整zheng流liu管guan到dao輸shu出chu電dian感gan到dao輸shu出chu電dian容rong返fan回hui變bian壓ya器qi電dian路lu中zhongX電容要盡量接近開關電源輸入端，輸入線應避免與其他電路平行，應避開。Y電容應放置在機殼接地端子或FG連接端。共摸電感應與變壓器保持一定距離，以避免磁偶合。

輸(shu)出(chu)電(dian)容(rong)一(yi)般(ban)可(ke)采(cai)用(yong)兩(liang)隻(zhi)一(yi)隻(zhi)靠(kao)近(jin)整(zheng)流(liu)管(guan)另(ling)一(yi)隻(zhi)應(ying)靠(kao)近(jin)輸(shu)出(chu)端(duan)子(zi)，可(ke)影(ying)響(xiang)電(dian)源(yuan)輸(shu)出(chu)紋(wen)波(bo)指(zhi)標(biao)，兩(liang)隻(zhi)小(xiao)容(rong)量(liang)電(dian)容(rong)並(bing)聯(lian)效(xiao)果(guo)應(ying)優(you)於(yu)用(yong)一(yi)隻(zhi)大(da)容(rong)量(liang)電(dian)容(rong)。發(fa)熱(re)器(qi)件(jian)要(yao)和(he)電(dian)解(jie)電(dian)容(rong)保(bao)持(chi)一(yi)定(ding)距(ju)離(li)，以(yi)延(yan)長(chang)整(zheng)機(ji)壽(shou)命(ming)
，電(dian)解(jie)電(dian)容(rong)是(shi)開(kai)關(guan)電(dian)源(yuan)壽(shou)命(ming)的(de)瓶(ping)勁(jin)，如(ru)變(bian)壓(ya)器(qi)、功率管、大功率電阻要和電解保持距離，電解之間也須留出散熱空間，條件允許可將其放置在進風口。
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PCB布(bu)線(xian)的(de)一(yi)些(xie)原(yuan)則(ze)印(yin)製(zhi)板(ban)設(she)計(ji)時(shi)，要(yao)考(kao)慮(lv)到(dao)幹(gan)擾(rao)對(dui)係(xi)統(tong)的(de)影(ying)響(xiang)
，將(jiang)電(dian)路(lu)的(de)模(mo)擬(ni)部(bu)分(fen)和(he)數(shu)字(zi)部(bu)分(fen)的(de)電(dian)路(lu)嚴(yan)格(ge)分(fen)開(kai)，對(dui)核(he)心(xin)電(dian)路(lu)重(zhong)點(dian)防(fang)護(hu)，將(jiang)係(xi)統(tong)地(di)線(xian)環(huan)繞(rao)，並(bing)布(bu)線(xian)盡(jin)可(ke)能(neng)粗(cu)，電(dian)源(yuan)增(zeng)加(jia)濾(lv)波(bo)電(dian)路(lu)
，采(cai)用(yong)DC-DC隔離，信號采用光電隔離，設計隔離電源，分析容易產生幹擾的部分(如時鍾電路、通訊電路等)和容易被幹擾的部分(如模擬采樣電路等)
，對dui這zhe兩liang種zhong類lei型xing的de電dian路lu分fen別bie采cai取qu措cuo施shi。對dui於yu幹gan擾rao元yuan件jian采cai取qu抑yi製zhi措cuo施shi
，對dui敏min感gan元yuan件jian采cai取qu隔ge離li和he保bao護hu措cuo施shi，並bing且qie將jiang它ta們men在zai空kong間jian和he電dian氣qi上shang拉la開kai距ju離li。在zai板ban級ji設she計ji時shi，還hai要yao注zhu意yi元yuan器qi件jian放fang置zhi要yao遠yuan離li印yin製zhi板ban邊bian沿yan，這zhe對dui防fang護hu空kong氣qi放fang電dian是shi有you利li的de。

隨著印製線路板製造工藝的不斷完善和提高，一般加工廠製造出線間距等於甚至小於0.1mm已經不存在什麼問題
，完全能夠滿足大多數應用場合。考慮到開關電源所采用的元器件及生產工藝，一般雙麵板最小線間距設為0.3mm，單麵板最小線間距設為0.5mm，焊盤與焊盤
、焊盤與過孔或過孔與過孔，最小間距設為 0.5mm
，可避免在焊接操作過程中出現“橋接”現(xian)象(xiang)。，這(zhe)樣(yang)大(da)多(duo)數(shu)製(zhi)板(ban)廠(chang)都(dou)能(neng)夠(gou)很(hen)輕(qing)鬆(song)滿(man)足(zu)生(sheng)產(chan)要(yao)求(qiu)，並(bing)可(ke)以(yi)把(ba)成(cheng)品(pin)率(lv)控(kong)製(zhi)得(de)非(fei)常(chang)高(gao)


，亦(yi)可(ke)實(shi)現(xian)合(he)理(li)的(de)布(bu)線(xian)密(mi)度(du)及(ji)有(you)一(yi)個(ge)較(jiao)經(jing)濟(ji)的(de)成(cheng)本(ben)。

最小線間距隻適合信號控製電路和電壓低於63V的低壓電路，當線間電壓大於該值時一般可按照500V/1mm經驗值取線間距。

方法一：shangwentidaodexianlubankaicaodefangfashiyongyuyixiejianjubugoudechanghe
，shunbiantiyixia
，gaifayechangyonglaizuoweibaohufangdianjianxi，changjianyudianshijixianxiangguanweibanhedianyuanjiaoliushuruchu。gaifazaimokuaidianyuanzhongdedaoleguangfandeyingyong，zaiguanfengdetiaojianxiakehuodehenhaodexiaoguo。

方法二：墊絕緣紙，可采用青殼紙、聚脂膜、聚(ju)四(si)氟(fu)乙(yi)烯(xi)定(ding)向(xiang)膜(mo)等(deng)絕(jue)緣(yuan)材(cai)料(liao)。一(yi)般(ban)通(tong)用(yong)電(dian)源(yuan)用(yong)青(qing)殼(ke)紙(zhi)或(huo)聚(ju)脂(zhi)膜(mo)墊(dian)在(zai)線(xian)路(lu)板(ban)於(yu)金(jin)屬(shu)機(ji)殼(ke)間(jian)，這(zhe)種(zhong)材(cai)料(liao)有(you)機(ji)械(xie)強(qiang)度(du)高(gao)，有(you)一(yi)定(ding)抗(kang)潮(chao)濕(shi)的(de)能(neng)力(li)。聚(ju)四(si)氟(fu)乙(yi)烯(xi)定(ding)向(xiang)膜(mo)由(you)於(yu)具(ju)有(you)耐(nai)高(gao)溫(wen)的(de)特(te)性(xing)在(zai)模(mo)塊(kuai)電(dian)源(yuan)中(zhong)得(de)到(dao)廣(guang)泛(fan)的(de)應(ying)用(yong)。在(zai)元(yuan)件(jian)和(he)周(zhou)圍(wei)導(dao)體(ti)間(jian)也(ye)可(ke)墊(dian)絕(jue)緣(yuan)薄(bo)膜(mo)來(lai)提(ti)高(gao)絕(jue)緣(yuan)抗(kang)電(dian)性(xing)能(neng)。

zuijinjinian
，suizheduocengxianlubanzaikaiguandianyuandianluzhongyingyong，shideyinzhixianlubianyaqichengweikeneng，youyuduocengban，cengjianjujiaoxiao
，yekeyichongfenliyongbianyaqichuangkoujiemian，kezaizhuxianlubanshangzaijiayidaoliangpianyouduocengbanzuchengdeyinzhixianquandadaoliyongchuangkou，jiangdixianludianliumidudemude
，youyucaiyongyinzhixianquan，jianshaolerengongganyu，bianyaqiyizhixinghao，pingmianjiegou，lougandi
，ouhehao。kaiqishicixin，lianghaodesanretiaojian。youyuqijuyouzhuduodeyoushi，youliyudapiliangshengchan，suoyidedaoguangfandeyingyong。danyanzhikaifachuqitourujiaoda，bushihexiaoguimoshengchan。

反fan激ji電dian源yuan反fan射she電dian壓ya還hai有you一yi個ge確que定ding因yin素su軍jun用yong開kai關guan電dian源yuan的de反fan射she電dian壓ya還hai與yu一yi個ge參can數shu有you關guan
，那na就jiu是shi輸shu出chu電dian壓ya
，輸shu出chu電dian壓ya越yue低di則ze變bian壓ya器qi匝za數shu比bi越yue大da，變bian壓ya器qi漏lou感gan越yue大da，開kai關guan管guan承cheng受shou電dian壓ya越yue高gao
，有you可ke能neng擊ji穿chuan開kai關guan管guan、xishoudianluxiaohaogonglvyueda，youkenengshixishouhuilugonglvqijianyongjiushixiao。zaishejidiyashuchuxiaogonglvfanjidianyuandeyouhuaguochengzhongbixuxiaoxinchuli，qichulifangfayoujige：

A、采(cai)用(yong)大(da)一(yi)個(ge)功(gong)率(lv)等(deng)級(ji)的(de)磁(ci)芯(xin)降(jiang)低(di)漏(lou)感(gan)
，這(zhe)樣(yang)可(ke)提(ti)高(gao)低(di)壓(ya)反(fan)激(ji)電(dian)源(yuan)的(de)轉(zhuan)換(huan)效(xiao)率(lv)
，降(jiang)低(di)損(sun)耗(hao)，減(jian)小(xiao)輸(shu)出(chu)紋(wen)波(bo)，提(ti)高(gao)多(duo)路(lu)輸(shu)出(chu)電(dian)源(yuan)的(de)交(jiao)差(cha)調(tiao)整(zheng)率(lv)，一(yi)般(ban)常(chang)見(jian)於(yu)家(jia)電(dian)用(yong)開(kai)關(guan)電(dian)源(yuan)，如(ru)光(guang)碟(die)機(ji)、DVB機頂盒等。

B、如(ru)果(guo)條(tiao)件(jian)不(bu)允(yun)許(xu)加(jia)大(da)磁(ci)芯(xin)，隻(zhi)能(neng)降(jiang)低(di)反(fan)射(she)電(dian)壓(ya)
，減(jian)小(xiao)占(zhan)空(kong)比(bi)。降(jiang)低(di)反(fan)射(she)電(dian)壓(ya)可(ke)減(jian)小(xiao)漏(lou)感(gan)但(dan)有(you)可(ke)能(neng)使(shi)電(dian)源(yuan)轉(zhuan)換(huan)效(xiao)率(lv)降(jiang)低(di)，這(zhe)兩(liang)者(zhe)是(shi)一(yi)個(ge)矛(mao)盾(dun)，必(bi)須(xu)要(yao)有(you)一(yi)個(ge)替(ti)代(dai)過(guo)程(cheng)才(cai)能(neng)找(zhao)到(dao)一(yi)個(ge)合(he)適(shi)的(de)點(dian)，在(zai)變(bian)壓(ya)器(qi)替(ti)代(dai)實(shi)驗(yan)過(guo)程(cheng)中(zhong)，可(ke)以(yi)檢(jian)測(ce)變(bian)壓(ya)器(qi)原(yuan)邊(bian)的(de)反(fan)峰(feng)電(dian)壓(ya)
，盡(jin)量(liang)降(jiang)低(di)反(fan)峰(feng)電(dian)壓(ya)脈(mai)衝(chong)的(de)寬(kuan)度(du)
，和(he)幅(fu)度(du)，可(ke)增(zeng)加(jia)變(bian)換(huan)器(qi)的(de)工(gong)作(zuo)安(an)全(quan)裕(yu)度(du)。一(yi)般(ban)反(fan)射(she)電(dian)壓(ya)在(zai)110V時比較合適。

C、增強耦合，降低損耗，采用新的技術

，和繞線工藝，變壓器為滿足安全規範會在原邊和副邊間采取絕緣措施
，如墊絕緣膠帶、jiajueyuanduankongjiaodai。zhexiejiangyingxiangbianyaqilouganxingneng，xianshishengchanzhongkecaiyongchujiraozubaoraocijideraofa。huozhecijiyongsanzhongjueyuanxianraozhi
，quxiaochucijijiandejueyuanwu，keyizengqiangouhe

，shenzhikecaiyongkuantongpiraozhi。
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反fan激ji電dian源yuan變bian壓ya器qi磁ci芯xin在zai工gong作zuo在zai單dan向xiang磁ci化hua狀zhuang態tai
，所suo以yi磁ci路lu需xu要yao開kai氣qi隙xi
，類lei似si於yu脈mai動dong直zhi流liu電dian感gan器qi。部bu分fen磁ci路lu通tong過guo空kong氣qi縫feng隙xi耦ou合he。為wei什shen麼me開kai氣qi隙xi的de原yuan理li本ben人ren理li解jie為wei：由於功率鐵氧體也具有近似於矩形的工作特性曲線(磁滯回線)，在工作特性曲線上Y軸表示磁感應強度(B)
，現在的生產工藝一般飽和點在400mT以上
，一般此值在設計中取值應該在200-300mT比較合適、X軸表示磁場強度(H)此值與磁化電流強度成比例關係。磁路開氣隙相當於把磁體磁滯回線向X軸zhou向xiang傾qing斜xie
，在zai同tong樣yang的de磁ci感gan應ying強qiang度du下xia，可ke承cheng受shou更geng大da的de磁ci化hua電dian流liu，則ze相xiang當dang於yu磁ci心xin儲chu存cun更geng多duo的de能neng量liang，此ci能neng量liang在zai開kai關guan管guan截jie止zhi時shi通tong過guo變bian壓ya器qi次ci級ji瀉xie放fang到dao負fu載zai電dian路lu
，反fan激ji電dian源yuan磁ci芯xin開kai氣qi隙xi有you兩liang個ge作zuo用yong。

fanjidianyuandebianyaqigongzuozaidanxiangcihuazhuangtai，bujinyaotongguociouhechuandinengliang
，haidanfudianyabianhuanshurushuchugelideduozhongzuoyong。suoyiqixidechulixuyaofeichangxiaoxin
，qixitaidakeshilouganbianda

，cizhisunhaozengjia，tiesun
、銅損增大，影響電源的整機性能。氣隙太小有可能使變壓器磁芯飽和
，導致電源損壞。

所suo謂wei反fan激ji電dian源yuan的de連lian續xu與yu斷duan續xu模mo式shi是shi指zhi變bian壓ya器qi的de工gong作zuo狀zhuang態tai，在zai滿man載zai狀zhuang態tai變bian壓ya器qi工gong作zuo於yu能neng量liang完wan全quan傳chuan遞di，或huo不bu完wan全quan傳chuan遞di的de工gong作zuo模mo式shi。一yi般ban要yao根gen據ju工gong作zuo環huan境jing進jin行xing設she計ji，常chang規gui反fan激ji電dian源yuan應ying該gai工gong作zuo在zai連lian續xu模mo式shi
，這zhe樣yang開kai關guan管guan
、xianludesunhaodoubijiaoxiao，erqiekeyijianqingshurushuchudianrongdegongzuoyingli
，danshizheyeyouyixieliwai。youyuzhizaogongyitedian，gaofanyaerjiguan，fanxianghuifushijianchang，sududi，zaidianliulianxuzhuangtai
，erjiguanshizaiyouzhengxiangpianyashihuifu，fanxianghuifushidenengliangsunhaofeichangda
，buliyubianhuanqixingnengdetigao
，qingzejiangdizhuanhuanxiaolv，zhengliuguanyanzhongfare，zhongzeshenzhishaohuizhengliuguan。youyuzaiduanxumoshixia，erjiguanshizailingpianyaqingkuangxiafanxiangpianzhi，sunhaokeyijiangdaoyigebijiaodideshuiping。

反fan激ji開kai關guan電dian源yuan變bian壓ya器qi應ying工gong作zuo在zai連lian續xu模mo式shi，那na就jiu要yao求qiu比bi較jiao大da的de繞rao組zu電dian感gan量liang，當dang然ran連lian續xu也ye是shi有you一yi定ding程cheng度du的de，過guo分fen追zhui求qiu絕jue對dui連lian續xu是shi不bu現xian實shi的de，有you可ke能neng需xu要yao很hen大da的de磁ci芯xin，非fei常chang多duo的de線xian圈quan匝za數shu，同tong時shi伴ban隨sui著zhe大da的de漏lou感gan和he分fen布bu電dian容rong，可ke能neng得de不bu償chang失shi。那na麼me如ru何he確que定ding這zhe個ge參can數shu呢ne

，通tong過guo多duo次ci實shi踐jian，及ji分fen析xi同tong行xing的de設she計ji
，本ben人ren認ren為wei，在zai標biao稱cheng電dian壓ya輸shu入ru時shi，輸shu出chu達da到dao50%~60%變壓器從斷續，過渡到連續狀態比較合適。

benpianwenzhangcongjiegoudaodianlubandesheji，yilujieshaoleruhejiangkaiguandianyuanjinxinghelidesheji。binggeichuleleyixiewentidejiejuefangfa。keyishuobaohanleyigekaiguandianyuanshejidequanbuguocheng
，congshejiheshijishengchandoujinxinglexiangxidejieshao，duixinshoulaishuoshibukeduodedebaoguizhishi，xiwangdajianengcongbenpianwenzhangdangzhongxuexidaohelishejikaiguandianyuandefangfa，bingjiayilinghuoyunyong。