電源適配器整流技術你了解嗎?電源適配器的負載怎樣?
電源適配器整流器(qi)(qi)是(shi)(shi)電源(yuan)系(xi)統中最重要(yao)的部分,因(yin)此,一些自(zi)主開發的廠商很(hen)注重電源(yuan)適(shi)配器(qi)(qi)整流器(qi)(qi)技(ji)術性能的改進,其(qi)目的是(shi)(shi)使(shi)電源(yuan)適(shi)配器(qi)(qi)整流器(qi)(qi)的可靠性和效(xiao)率(lv)得到很(hen)大提高,使(shi)其(qi)成本和高頻(pin)電磁干擾降低(di)。那你對電源(yuan)適(shi)配器(qi)(qi)整流技(ji)術了(le)解多少?電源(yuan)適(shi)配器(qi)(qi)的負載怎(zen)樣?
電源適配器整流技術
1、恒功率整流器技術
恒(heng)功(gong)率(lv)(lv)整流器(qi),其突出(chu)(chu)特點是(shi)在規(gui)定(ding)的(de)交流輸入電壓和直流輸出(chu)(chu)電壓范圍(wei)內均能給(gei)出(chu)(chu)定(ding)功(gong)率(lv)(lv)?這種采用恒(heng)功(gong)率(lv)(lv)設(she)計的(de)新型智(zhi)能高頻電源適配器(qi)系統(tong),是(shi)電源適配器(qi)構思上的(de)一個飛(fei)躍,也是(shi)現代(dai)電源適配器(qi)設(she)備的(de)最優選擇?
在(zai)普通限(xian)流(liu)(liu)(liu)型整流(liu)(liu)(liu)器(qi)中(zhong),其輸出特性(xing)可分為兩類,即(ji)恒流(liu)(liu)(liu)和恒壓(ya)特性(xing)?在(zai)恒流(liu)(liu)(liu)普通限(xian)流(liu)(liu)(liu)型整流(liu)(liu)(liu)器(qi)中(zhong),其輸出電(dian)(dian)流(liu)(liu)(liu)保持不變;在(zai)恒壓(ya)普通限(xian)流(liu)(liu)(liu)型整流(liu)(liu)(liu)器(qi)中(zhong),其輸出電(dian)(dian)壓(ya)保持不變?在(zai)恒流(liu)(liu)(liu)普通限(xian)流(liu)(liu)(liu)型整流(liu)(liu)(liu)器(qi)中(zhong),如果負載電(dian)(dian)流(liu)(liu)(liu)超過(guo)限(xian)流(liu)(liu)(liu)值,則整流(liu)(liu)(liu)器(qi)輸出電(dian)(dian)壓(ya)將(jiang)隨電(dian)(dian)流(liu)(liu)(liu)增加而快速下(xia)降(jiang),直到整流(liu)(liu)(liu)器(qi)過(guo)流(liu)(liu)(liu)而關閉?其額定電(dian)(dian)流(liu)(liu)(liu)?限(xian)定電(dian)(dian)流(liu)(liu)(liu)及(ji)過(guo)流(liu)(liu)(liu)值都很接(jie)近(jin)
恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)整(zheng)流(liu)器(qi)(qi)與限(xian)流(liu)型(xing)整(zheng)流(liu)器(qi)(qi)的(de)(de)(de)(de)不(bu)同之處,是在恒(heng)(heng)(heng)(heng)(heng)壓和恒(heng)(heng)(heng)(heng)(heng)流(liu)階(jie)段(duan)中插(cha)入一(yi)個(ge)恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)階(jie)段(duan),這就是所謂的(de)(de)(de)(de)恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)整(zheng)流(liu)器(qi)(qi)?該整(zheng)流(liu)器(qi)(qi)工作在三個(ge)不(bu)同輸(shu)出(chu)(chu)階(jie)段(duan),即恒(heng)(heng)(heng)(heng)(heng)壓?恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)和恒(heng)(heng)(heng)(heng)(heng)流(liu)階(jie)段(duan)?恒(heng)(heng)(heng)(heng)(heng)壓和恒(heng)(heng)(heng)(heng)(heng)流(liu)階(jie)段(duan)的(de)(de)(de)(de)工作情況與限(xian)流(liu)型(xing)整(zheng)流(liu)器(qi)(qi)完全相同所不(bu)同的(de)(de)(de)(de)是在恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)階(jie)段(duan),整(zheng)流(liu)器(qi)(qi)輸(shu)出(chu)(chu)功(gong)(gong)率(lv)(lv)保持不(bu)變?例如,恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)整(zheng)流(liu)器(qi)(qi)的(de)(de)(de)(de)輸(shu)出(chu)(chu)電(dian)壓可從60V隨著電(dian)流(liu)增加(jia)而線性地減(jian)小(xiao)至43V?此(ci)時,系(xi)(xi)統(tong)仍處在正(zheng)常工作狀(zhuang)態?因此(ci),采用恒(heng)(heng)(heng)(heng)(heng)功(gong)(gong)率(lv)(lv)整(zheng)流(liu)器(qi)(qi)設計的(de)(de)(de)(de)電(dian)源適(shi)(shi)配(pei)器(qi)(qi)系(xi)(xi)統(tong),一(yi)般只需考慮電(dian)子設備最大(da)負載(zai)和整(zheng)流(liu)器(qi)(qi)的(de)(de)(de)(de)冗余(yu),就可以確定(ding)(ding)電(dian)源系(xi)(xi)統(tong)的(de)(de)(de)(de)額(e)定(ding)(ding)輸(shu)出(chu)(chu)功(gong)(gong)率(lv)(lv)?這與采用限(xian)流(liu)型(xing)電(dian)源適(shi)(shi)配(pei)器(qi)(qi)系(xi)(xi)統(tong)相比較,所需的(de)(de)(de)(de)整(zheng)流(liu)功(gong)(gong)率(lv)(lv)和整(zheng)流(liu)模塊數量至少(shao)可以減(jian)少(shao)33%以上(shang),這也就極(ji)大(da)地節約了投資?
2、倍流整流器技術
通常DC/DC變(bian)(bian)換(huan)(huan)器(qi)(qi)是一(yi)個全(quan)橋(qiao)功(gong)率變(bian)(bian)換(huan)(huan)器(qi)(qi),高頻變(bian)(bian)壓器(qi)(qi)次(ci)(ci)級(ji)也常使用全(quan)波整流(liu)技(ji)術?因此,在普通整流(liu)器(qi)(qi)中,高頻變(bian)(bian)壓器(qi)(qi)次(ci)(ci)級(ji)繞組(zu)必須(xu)有一(yi)個中心抽頭并與電路(lu)參考電壓(地)相連?中心抽頭把高頻變(bian)(bian)壓器(qi)(qi)次(ci)(ci)級(ji)繞組(zu)分成(cheng)兩個電感器(qi)(qi)?
倍流(liu)整流(liu)器(qi)由一個(ge)(ge)沒有中心抽頭的高頻變(bian)壓器(qi)次級繞組?兩個(ge)(ge)電感(gan)量相等而(er)且同繞在一個(ge)(ge)磁(ci)芯上的電感(gan)器(qi)?兩個(ge)(ge)整流(liu)二極(ji)管和(he)輸出電容(rong)器(qi)組成?
倍流(liu)(liu)整(zheng)流(liu)(liu)器(qi)(qi)最突出(chu)(chu)的(de)(de)特點是(shi)高頻變(bian)壓(ya)器(qi)(qi)次級繞(rao)組沒有中心抽頭(tou),而(er)且流(liu)(liu)過變(bian)壓(ya)器(qi)(qi)線圈和濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)的(de)(de)電(dian)(dian)(dian)流(liu)(liu)只是(shi)輸(shu)出(chu)(chu)負載電(dian)(dian)(dian)流(liu)(liu)的(de)(de)一半?因此(ci),大(da)(da)大(da)(da)簡化(hua)了高頻變(bian)壓(ya)器(qi)(qi)和濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)的(de)(de)結構設計?但電(dian)(dian)(dian)路中需(xu)多加一個濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)?兩(liang)個濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)的(de)(de)電(dian)(dian)(dian)感總(zong)值(zhi)可(ke)等于(yu)或(huo)略小于(yu)普通(tong)全波(bo)(bo)(bo)整(zheng)流(liu)(liu)器(qi)(qi)扼流(liu)(liu)圈的(de)(de)電(dian)(dian)(dian)感值(zhi),因為流(liu)(liu)過兩(liang)個濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)的(de)(de)電(dian)(dian)(dian)流(liu)(liu)的(de)(de)工作頻率和變(bian)化(hua)速度均較低?倍流(liu)(liu)整(zheng)流(liu)(liu)器(qi)(qi)的(de)(de)輸(shu)出(chu)(chu)電(dian)(dian)(dian)流(liu)(liu)是(shi)兩(liang)個濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)電(dian)(dian)(dian)流(liu)(liu)的(de)(de)總(zong)和,而(er)兩(liang)個濾波(bo)(bo)(bo)電(dian)(dian)(dian)感器(qi)(qi)的(de)(de)脈(mo)動(dong)電(dian)(dian)(dian)流(liu)(liu)是(shi)相消的(de)(de)?因此(ci),直(zhi)流(liu)(liu)輸(shu)出(chu)(chu)脈(mo)動(dong)電(dian)(dian)(dian)流(liu)(liu)也較低?
電源適配器的負載一一分析
1、變壓器的工藝問題
①浸漆烘(hong)干不到位,導致磁芯不牢固(gu)引起機械(xie)振動而發出響聲(sheng);
②氣隙的長度不適合,導致變壓器的工作狀態不穩定而發出(chu)響聲;
③線包沒(mei)有(you)繞(rao)緊也(ye)可(ke)能導(dao)致(zhi)響聲(sheng);
④磁芯(xin)(xin)組合有氣(qi)隙(xi)存在,高(gao)頻時引起空氣(qi)振動(dong)而發(fa)出響聲(變壓器如果經過(guo)真空全浸、并(bing)中柱點環氧樹(shu)脂、骨架(jia)與磁芯(xin)(xin)間點環氧樹(shu)脂--參考下圖框(kuang)出來的(de)位置,一般不會(hui)發(fa)聲)。
2、變壓器的環路問題
變壓器(qi)的(de)環路(lu)問題即(ji)指變壓器(qi)的(de)環路(lu)發生(sheng)振蕩(dang)從而引起變壓器(qi)發生(sheng)嘯叫。
①電路板(ban)布線(xian)不當,從而造成干擾引發(fa)振(zhen)蕩,導致響(xiang)聲;
②反饋(kui)回路參數(shu)設置不當,導致環路不穩定以致產生振蕩而發出(chu)響聲;
③環路(lu)中元器件(jian)的(de)質(zhi)(zhi)量(liang)(liang)問(wen)題(ti),如輸入濾波電(dian)容(rong)(rong)容(rong)(rong)量(liang)(liang)不足,輸出整(zheng)流快恢復(fu)二(er)極管質(zhi)(zhi)量(liang)(liang)不好,功率MOS管質(zhi)(zhi)量(liang)(liang)不好,RCD反沖吸收回路(lu)的(de)高壓(ya)電(dian)容(rong)(rong)或二(er)極管質(zhi)(zhi)量(liang)(liang)不好等等,這些問(wen)題(ti)都有可能導致震蕩(dang)而引起響聲。
3、變壓器的鐵心問題
變(bian)壓器(qi)(qi)鐵心發(fa)生(sheng)飽和時,線圈中電流增(zeng)大,變(bian)壓器(qi)(qi)發(fa)熱(re)并產生(sheng)自激震蕩,線圈的振蕩引起周圍空氣的振動從而發(fa)出響聲。
4、電源適配器的負載問題
①電(dian)源適(shi)配器在空載(zai)或輕載(zai)的情況下(xia),在某些工(gong)作(zuo)點(dian)處會發生振蕩現象,表現為變壓(ya)器的嘯(xiao)叫和輸出的不穩定。
發生這(zhe)種現象是由于空載/輕載時(shi)(shi),開(kai)(kai)關(guan)瞬時(shi)(shi)開(kai)(kai)通時(shi)(shi)間(jian)(jian)過大(da)(da)從而造成輸出(chu)能量太(tai)大(da)(da),進而電壓過沖也很(hen)大(da)(da),需要(yao)較長(chang)的(de)(de)時(shi)(shi)間(jian)(jian)去恢復到(dao)正常電壓,因此開(kai)(kai)關(guan)需停止(zhi)工作(zuo)一段時(shi)(shi)間(jian)(jian),這(zhe)樣開(kai)(kai)關(guan)就工作(zuo)于間(jian)(jian)歇性工作(zuo)模式(shi),使(shi)變(bian)壓器發生較低頻(pin)率(有(you)規律的(de)(de)間(jian)(jian)歇性全(quan)截(jie)止(zhi)周期或占空比劇(ju)烈(lie)變(bian)化的(de)(de)頻(pin)率)的(de)(de)振動。
②變壓器工作(zuo)在嚴重(zhong)的超(chao)載狀態(tai),時(shi)刻(ke)都有燒(shao)毀的可能——這就是許多電(dian)源燒(shao)毀前“慘叫”的由來。
對電源適配(pei)器的介紹就(jiu)到這里,如果您(nin)還有什么疑問可以聯系我們(men),我們(men)會為(wei)您(nin)相(xiang)信解答(da)!