一、前言

　　開關電源系(xi)(xi)統(tong)是弱電(dian)(dian)(dian)控(kong)(kong)(kong)制(zhi)(zhi)強(qiang)電(dian)(dian)(dian)的(de)(de)(de)(de)(de)(de)系(xi)(xi)統(tong)。開(kai)關電(dian)(dian)(dian)源(yuan)系(xi)(xi)統(tong)主(zhu)要(yao)(yao)可(ke)以分為主(zhu)功(gong)(gong)(gong)率(lv)(lv)(lv)電(dian)(dian)(dian)路(lu)(lu)和(he)控(kong)(kong)(kong)制(zhi)(zhi)電(dian)(dian)(dian)路(lu)(lu)兩部分。主(zhu)功(gong)(gong)(gong)率(lv)(lv)(lv)電(dian)(dian)(dian)路(lu)(lu)是由(you)變(bian)(bian)換(huan)器構成(cheng)。變(bian)(bian)換(huan)器是應用功(gong)(gong)(gong)率(lv)(lv)(lv)半(ban)(ban)導(dao)體(ti)器件(jian)，對(dui)電(dian)(dian)(dian)能進行變(bian)(bian)換(huan)的(de)(de)(de)(de)(de)(de)裝(zhuang)(zhuang)置(zhi)(zhi)，變(bian)(bian)換(huan)量包括電(dian)(dian)(dian)壓、電(dian)(dian)(dian)流、頻率(lv)(lv)(lv)和(he)波形(xing)等方(fang)(fang)面，以達到電(dian)(dian)(dian)能更好(hao)符合各種不(bu)同用電(dian)(dian)(dian)設備要(yao)(yao)求的(de)(de)(de)(de)(de)(de)目的(de)(de)(de)(de)(de)(de)。這(zhe)是通(tong)過對(dui)功(gong)(gong)(gong)率(lv)(lv)(lv)半(ban)(ban)導(dao)體(ti)器件(jian)的(de)(de)(de)(de)(de)(de)開(kai)關的(de)(de)(de)(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)來(lai)實(shi)現(xian)的(de)(de)(de)(de)(de)(de)。因此主(zhu)功(gong)(gong)(gong)率(lv)(lv)(lv)電(dian)(dian)(dian)路(lu)(lu)是開(kai)關電(dian)(dian)(dian)源(yuan)控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)中的(de)(de)(de)(de)(de)(de)被(bei)控(kong)(kong)(kong)對(dui)象，而控(kong)(kong)(kong)制(zhi)(zhi)功(gong)(gong)(gong)率(lv)(lv)(lv)半(ban)(ban)導(dao)體(ti)器件(jian)的(de)(de)(de)(de)(de)(de)開(kai)關以實(shi)現(xian)既定的(de)(de)(de)(de)(de)(de)性能是控(kong)(kong)(kong)制(zhi)(zhi)裝(zhuang)(zhuang)置(zhi)(zhi)的(de)(de)(de)(de)(de)(de)主(zhu)要(yao)(yao)工作。將被(bei)控(kong)(kong)(kong)對(dui)象和(he)控(kong)(kong)(kong)制(zhi)(zhi)裝(zhuang)(zhuang)置(zhi)(zhi)按照一定的(de)(de)(de)(de)(de)(de)方(fang)(fang)式(shi)連接起(qi)來(lai)，組成(cheng)一個(ge)有機(ji)的(de)(de)(de)(de)(de)(de)總體(ti)，就(jiu)構成(cheng)開(kai)關電(dian)(dian)(dian)源(yuan)的(de)(de)(de)(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)，這(zhe)樣的(de)(de)(de)(de)(de)(de)電(dian)(dian)(dian)路(lu)(lu)即為控(kong)(kong)(kong)制(zhi)(zhi)電(dian)(dian)(dian)路(lu)(lu)。控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)的(de)(de)(de)(de)(de)(de)工作方(fang)(fang)式(shi)有多種，其中最基(ji)本(ben)的(de)(de)(de)(de)(de)(de)一種是基(ji)于反饋控(kong)(kong)(kong)制(zhi)(zhi)原理(li)的(de)(de)(de)(de)(de)(de)閉(bi)環控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)。而大(da)部分的(de)(de)(de)(de)(de)(de)開(kai)關電(dian)(dian)(dian)源(yuan)控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)是閉(bi)環控(kong)(kong)(kong)制(zhi)(zhi)系(xi)(xi)統(tong)。

　　二、閉環控制原理

　　通常，我(wo)們把被控(kong)量(liang)(liang)(liang)送回到控(kong)制(zhi)系統的(de)(de)輸入(ru)端(duan)，與(yu)參(can)據(ju)量(liang)(liang)(liang)相比較產生誤差(cha)信號的(de)(de)過程(cheng)，稱為(wei)(wei)反饋。若反饋的(de)(de)信號是與(yu)參(can)據(ju)量(liang)(liang)(liang)相減，使得產生的(de)(de)偏差(cha)越(yue)來越(yue)小(xiao)，稱為(wei)(wei)負反饋。由(you)于引入(ru)了被控(kong)量(liang)(liang)(liang)的(de)(de)反饋信息(xi)，整個控(kong)制(zhi)過程(cheng)成(cheng)為(wei)(wei)閉合的(de)(de)，因此也稱閉環(huan)控(kong)制(zhi)，如圖1所示。

圖(tu)1  反饋控制框圖(tu)

　　三、基本組成

　　控(kong)制裝置(zhi)是由具有一定職(zhi)能的各種基本元器件組(zu)成。系統的元器件按照(zhao)職(zhi)能分類主要有以下(xia)幾種：

　　測量(liang)單元：其職能是檢測被控制的(de)物理(li)量(liang)。這個(ge)被控量(liang)一(yi)般為(wei)主(zhu)功率電(dian)路的(de)輸出電(dian)壓、主(zhu)功率電(dian)路的(de)輸入電(dian)流(liu)等。

　　給(gei)定單元：其職能(neng)是給(gei)出與期(qi)望的被控量(liang)相對應的參據量(liang)，即給(gei)定量(liang)。在開關(guan)電源系(xi)統中(zhong)，給(gei)定量(liang)一般為直流常量(liang)或(huo)者是交(jiao)流正弦量(liang)。

　　比較(jiao)單元：其職(zhi)能(neng)是將(jiang)檢(jian)測到(dao)的被控制量(liang)的實(shi)際(ji)值與參(can)據(ju)量(liang)進行(xing)比較(jiao)，求出他們之間的偏差。

　　校正(zheng)單元：即補償單元，用串聯(lian)方(fang)(fang)(fang)式或(huo)者反饋方(fang)(fang)(fang)式（并聯(lian)方(fang)(fang)(fang)式）等方(fang)(fang)(fang)式連(lian)接在系統中，以(yi)(yi)改善(shan)系統的性(xing)能。這(zhe)(zhe)個補償網(wang)(wang)絡是控制系統的核心(xin)部(bu)(bu)分，是決(jue)定控制系統性(xing)能的關鍵部(bu)(bu)分。可(ke)以(yi)(yi)通過由電阻、電容組成(cheng)的無源或(huo)有源網(wang)(wang)絡實(shi)現，也可(ke)以(yi)(yi)通過MCU、DSP這(zhe)(zhe)些數字器件輔助實(shi)現。

　　四、外作用類型

　　一(yi)(yi)般加(jia)在開關(guan)電(dian)(dian)(dian)源系(xi)(xi)統(tong)上的(de)外(wai)作用有兩種(zhong)(zhong)類型：一(yi)(yi)種(zhong)(zhong)是有用輸入(ru)(ru)，它(ta)決定系(xi)(xi)統(tong)被控量(liang)的(de)變化規律，比如(ru)給(gei)定量(liang)；一(yi)(yi)種(zhong)(zhong)是系(xi)(xi)統(tong)不(bu)希望有的(de)外(wai)作用，即擾動，它(ta)破壞有用輸入(ru)(ru)對系(xi)(xi)統(tong)的(de)控制。在實(shi)際系(xi)(xi)統(tong)中(zhong)，擾動是不(bu)可避(bi)免(mian)的(de)。這(zhe)樣(yang)的(de)擾動包括：主功(gong)率電(dian)(dian)(dian)路輸入(ru)(ru)電(dian)(dian)(dian)壓的(de)波(bo)動，主功(gong)率電(dian)(dian)(dian)路輸出電(dian)(dian)(dian)流的(de)波(bo)動或(huo)者負(fu)載的(de)波(bo)動，元(yuan)器件參(can)數的(de)溫度漂移等。

      五、基本控制方式

　　反(fan)饋(kui)控(kong)制(zhi)是(shi)系統最(zui)(zui)基本的(de)控(kong)制(zhi)方式(shi)，也是(shi)應(ying)用最(zui)(zui)廣(guang)泛的(de)一種控(kong)制(zhi)方式(shi)。此(ci)外，還有開環控(kong)制(zhi)方式(shi)和(he)復合控(kong)制(zhi)方式(shi)，它們都有著各自的(de)特點和(he)不(bu)同(tong)的(de)應(ying)用場合。

　　（1）反(fan)饋控(kong)制方(fang)式

　　如前面所提及，反饋(kui)控(kong)制(zhi)(zhi)方式是(shi)按照(zhao)偏差(cha)進行(xing)控(kong)制(zhi)(zhi)的，其特點(dian)是(shi)不論什么原因使(shi)被控(kong)量(liang)偏離期(qi)望(wang)值(zhi)而出現偏差(cha)時，必定(ding)會(hui)產(chan)(chan)生一個相應的控(kong)制(zhi)(zhi)作用去減小或消除(chu)這個偏差(cha)，使(shi)被控(kong)量(liang)與(yu)期(qi)望(wang)值(zhi)趨于一致。可(ke)見，按照(zhao)反饋(kui)控(kong)制(zhi)(zhi)方式設計的控(kong)制(zhi)(zhi)系統，具有(you)抑制(zhi)(zhi)任何(he)內、外擾動對被控(kong)量(liang)產(chan)(chan)生影響的能力，有(you)較高的穩態精度(du)。

　　如圖2所示為電壓(ya)(ya)型控制(zhi)Boost變換器控制(zhi)框(kuang)圖，電壓(ya)(ya)反饋控制(zhi)技術是(shi)開關電源系統中經(jing)典(dian)的(de)反饋控制(zhi)方(fang)法(fa)。這(zhe)是(shi)60年代后期開關穩(wen)壓(ya)(ya)電源剛剛開始發展就采用的(de)第一種控制(zhi)方(fang)法(fa)，該方(fang)法(fa)與一些必要(yao)的(de)過電流保護(hu)電路相結合(he)，至今仍然被(bei)廣泛的(de)應用。

圖2  電壓型控制 Boost 變(bian)換器控制框圖

　　（2）開(kai)環控制(zhi)方式

　　開環控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)方式(shi)是指被控(kong)(kong)(kong)(kong)(kong)(kong)(kong)裝置(zhi)與(yu)被控(kong)(kong)(kong)(kong)(kong)(kong)(kong)對象之間只有(you)順向(xiang)作用(yong)而沒有(you)反向(xiang)聯(lian)系(xi)的(de)(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)過程(cheng)。按這種控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)方式(shi)組成的(de)(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)統(tong)(tong)(tong)稱(cheng)為(wei)開環控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)統(tong)(tong)(tong)，其(qi)特點是系(xi)統(tong)(tong)(tong)的(de)(de)(de)(de)輸(shu)出量(liang)不會對系(xi)統(tong)(tong)(tong)的(de)(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)作用(yong)發生(sheng)影響(xiang)。這種控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)方式(shi)也(ye)稱(cheng)為(wei)前(qian)饋(kui)(kui)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)、順饋(kui)(kui)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)。開環控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)統(tong)(tong)(tong)可以(yi)(yi)由按給定量(liang)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)方式(shi)組成，也(ye)可以(yi)(yi)由按擾動(dong)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)的(de)(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)(zhi)方式(shi)組成。

　　按(an)給定量控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)的(de)開環控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)，其(qi)控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)作用(yong)(yong)(yong)直接由(you)控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)系統(tong)的(de)輸入(ru)量產生，給定一個輸入(ru)量，就有一個輸出量與之相對應，控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)精(jing)度完(wan)全(quan)取決(jue)于控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)電路(lu)所(suo)用(yong)(yong)(yong)的(de)元(yuan)器件(jian)以及主功率(lv)電路(lu)的(de)特性，如圖(tu)3所(suo)示(shi)。這(zhe)種控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)方式(shi)沒有自(zi)動(dong)(dong)修正偏(pian)差的(de)能(neng)力，抗(kang)擾(rao)動(dong)(dong)能(neng)力差。但由(you)于其(qi)結構簡單、調整方便、成本低，在精(jing)度要求不高或擾(rao)動(dong)(dong)影響較小的(de)情(qing)況下，這(zhe)種控(kong)(kong)(kong)制(zhi)(zhi)(zhi)(zhi)方式(shi)還(huan)是有一定的(de)實用(yong)(yong)(yong)價(jia)值。

圖3  按(an)給定量控制的開環控制系統

如圖4所示的采(cai)用(yong)電容(rong)的開關功(gong)率(lv)變(bian)換器，一般(ban)為多級變(bian)換電路(lu)中(zhong)的其中(zhong)一級，通(tong)常采(cai)用(yong)開環控制(zhi)，效率(lv)和功(gong)率(lv)密度較(jiao)高，容(rong)易(yi)實(shi)現(xian)開關，具有(you)廣泛的應用(yong)前景。

圖4  開環控制的開關電容功率變換器(qi)

　　按擾(rao)動(dong)(dong)(dong)控(kong)制的(de)開環控(kong)制系(xi)統，是利(li)用(yong)(yong)可(ke)測量(liang)(liang)的(de)擾(rao)動(dong)(dong)(dong)量(liang)(liang)，產生一種(zhong)補償(chang)作(zuo)用(yong)(yong)，以減少或抵消(xiao)擾(rao)動(dong)(dong)(dong)對(dui)輸出量(liang)(liang)的(de)影響(xiang)，如圖5所(suo)示。這種(zhong)控(kong)制方(fang)式直接(jie)從擾(rao)動(dong)(dong)(dong)取得信息，并據此(ci)改變被控(kong)量(liang)(liang)，因(yin)此(ci)其(qi)抗擾(rao)動(dong)(dong)(dong)性好，控(kong)制精(jing)度也較高，但(dan)它只(zhi)適(shi)用(yong)(yong)于擾(rao)動(dong)(dong)(dong)是可(ke)以測量(liang)(liang)的(de)場合，而(er)且一個補償(chang)裝置只(zhi)能補償(chang)一個擾(rao)動(dong)(dong)(dong)因(yin)素(su)，對(dui)其(qi)余擾(rao)動(dong)(dong)(dong)均不起補償(chang)作(zuo)用(yong)(yong)。

圖(tu)5  按擾(rao)動(dong)控(kong)(kong)制的開環控(kong)(kong)制系(xi)統(tong)

　　如圖6所(suo)示為單周期控(kong)制(zhi)(zhi)(zhi)Buck變(bian)換器控(kong)制(zhi)(zhi)(zhi)框圖，單周期控(kong)制(zhi)(zhi)(zhi)技術(shu)實際上就是一(yi)種(zhong)(zhong)按擾動(dong)控(kong)制(zhi)(zhi)(zhi)的(de)(de)開(kai)環控(kong)制(zhi)(zhi)(zhi)系統。它將主功(gong)率(lv)(lv)(lv)電(dian)路(lu)的(de)(de)輸入電(dian)壓(ya)引入控(kong)制(zhi)(zhi)(zhi)，隨著輸入電(dian)壓(ya)的(de)(de)變(bian)化(hua)，得到不(bu)同的(de)(de)占空度，使得主功(gong)率(lv)(lv)(lv)電(dian)路(lu)的(de)(de)輸出電(dian)壓(ya)跟(gen)隨給定量。理(li)論上這(zhe)種(zhong)(zhong)控(kong)制(zhi)(zhi)(zhi)技術(shu)完全抵制(zhi)(zhi)(zhi)了主功(gong)率(lv)(lv)(lv)電(dian)路(lu)的(de)(de)輸出電(dian)壓(ya)擾動(dong)，但(dan)是對負(fu)載的(de)(de)擾動(dong)卻無能(neng)為力。

圖6  單周期控(kong)(kong)制 Buck 變換(huan)器控(kong)(kong)制框(kuang)圖

 （3）復合控制方式(shi)

　　開環控制方式在技術上較反饋控制方式簡單，且對激勵響應快，但是僅僅只采用按給定量控制的前饋控制方式來控制，系統控制精度不高。而按擾動控制的開環控制系統只適用于擾動可以測量的場合。因此，比較合理的一種控制方式是把開環控制方式與反饋控制方式結合起來。這種控制方式稱為復合控制。利用控制系統的給定量，產生一種補償作用，使得被控量更好的跟隨給定量。另外，對主要擾動采用適當的補償裝置來實現擾動控制。同時，再組成反饋控制系統實現按偏差控制，以消除其余擾動產生的偏差。這樣，系統的主要外作用已被補償，反饋控制系統比較容易設計，控制效果也會更好。這種將前饋控制和反饋控制相結合的控制方式稱為復合控制。
如圖7所示為(wei)具有輸(shu)(shu)(shu)(shu)入(ru)電(dian)壓(ya)(ya)(ya)前(qian)饋(kui)(kui)(kui)的(de)(de)(de)平均(jun)電(dian)流(liu)(liu)(liu)控(kong)(kong)(kong)制(zhi)(zhi)Boost變換(huan)器(qi)的(de)(de)(de)PFC控(kong)(kong)(kong)制(zhi)(zhi)框(kuang)圖，這(zhe)種(zhong)控(kong)(kong)(kong)制(zhi)(zhi)方法為(wei)雙環反(fan)饋(kui)(kui)(kui)的(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)方法，外環為(wei)母線電(dian)壓(ya)(ya)(ya)平均(jun)值(zhi)控(kong)(kong)(kong)制(zhi)(zhi)環，內(nei)環為(wei)輸(shu)(shu)(shu)(shu)入(ru)電(dian)流(liu)(liu)(liu)控(kong)(kong)(kong)制(zhi)(zhi)環。該控(kong)(kong)(kong)制(zhi)(zhi)方法將輸(shu)(shu)(shu)(shu)出(chu)電(dian)壓(ya)(ya)(ya)的(de)(de)(de)平均(jun)值(zhi)作為(wei)反(fan)饋(kui)(kui)(kui)與(yu)基(ji)準比較，產(chan)(chan)生的(de)(de)(de)誤差信號(hao)經(jing)由電(dian)壓(ya)(ya)(ya)補償器(qi)進(jin)行調(diao)節。產(chan)(chan)生的(de)(de)(de)信號(hao)與(yu)輸(shu)(shu)(shu)(shu)入(ru)電(dian)壓(ya)(ya)(ya)有效值(zhi)一起，控(kong)(kong)(kong)制(zhi)(zhi)正弦(xian)(xian)(xian)波基(ji)準的(de)(de)(de)幅值(zhi)。再將輸(shu)(shu)(shu)(shu)入(ru)電(dian)流(liu)(liu)(liu)作為(wei)反(fan)饋(kui)(kui)(kui)與(yu)正弦(xian)(xian)(xian)波基(ji)準進(jin)行比較，產(chan)(chan)生的(de)(de)(de)誤差信號(hao)經(jing)由電(dian)流(liu)(liu)(liu)補償器(qi)進(jin)行調(diao)節產(chan)(chan)生調(diao)制(zhi)(zhi)信號(hao)，再將該調(diao)制(zhi)(zhi)信號(hao)與(yu)載波比較得(de)到控(kong)(kong)(kong)制(zhi)(zhi)信號(hao)，得(de)到所需的(de)(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)信號(hao)，外環的(de)(de)(de)作用，主要控(kong)(kong)(kong)制(zhi)(zhi)輸(shu)(shu)(shu)(shu)出(chu)電(dian)壓(ya)(ya)(ya)，內(nei)環主要控(kong)(kong)(kong)制(zhi)(zhi)輸(shu)(shu)(shu)(shu)入(ru)電(dian)流(liu)(liu)(liu)的(de)(de)(de)波形(xing)，保證輸(shu)(shu)(shu)(shu)入(ru)電(dian)流(liu)(liu)(liu)的(de)(de)(de)正弦(xian)(xian)(xian)度(du)。引入(ru)了輸(shu)(shu)(shu)(shu)入(ru)電(dian)壓(ya)(ya)(ya)前(qian)饋(kui)(kui)(kui)，克服輸(shu)(shu)(shu)(shu)入(ru)電(dian)壓(ya)(ya)(ya)擾動(dong)對輸(shu)(shu)(shu)(shu)出(chu)電(dian)壓(ya)(ya)(ya)的(de)(de)(de)影響。

圖7  具有輸(shu)入電壓前饋的平均電流控(kong)制(zhi) Boost 變換器的PFC

　　六、校正方式

　　對控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)的(de)要(yao)求，通常以性(xing)能指標的(de)形(xing)(xing)式(shi)給(gei)出。而為(wei)(wei)了使系(xi)(xi)(xi)統(tong)(tong)(tong)獲得滿意(yi)的(de)性(xing)能，必須對控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)進(jin)行設計和(he)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)，也(ye)(ye)就是在(zai)(zai)系(xi)(xi)(xi)統(tong)(tong)(tong)中適當的(de)位(wei)置(zhi)(zhi)加進(jin)適當的(de)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)。校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)彌補(bu)了原系(xi)(xi)(xi)統(tong)(tong)(tong)的(de)性(xing)能缺陷。按照(zhao)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)在(zai)(zai)開(kai)關電源系(xi)(xi)(xi)統(tong)(tong)(tong)中的(de)連(lian)接(jie)(jie)方(fang)式(shi)，控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)的(de)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)方(fang)式(shi)可以分為(wei)(wei)串(chuan)聯校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、反饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、前(qian)(qian)饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、復合校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)等(deng)。如圖8所示(shi)(shi)(shi)為(wei)(wei)系(xi)(xi)(xi)統(tong)(tong)(tong)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)位(wei)置(zhi)(zhi)示(shi)(shi)(shi)意(yi)圖，G（S）為(wei)(wei)被控對象（主功率電路）；串(chuan)聯校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)一般連(lian)接(jie)(jie)在(zai)(zai)G（S）之(zhi)前(qian)(qian)，串(chuan)接(jie)(jie)與系(xi)(xi)(xi)統(tong)(tong)(tong)前(qian)(qian)向通道之(zhi)中，如G1（S）益(yi)所示(shi)(shi)(shi)；反饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)連(lian)接(jie)(jie)在(zai)(zai)系(xi)(xi)(xi)統(tong)(tong)(tong)局部反饋(kui)通路之(zhi)中，如G2（S）位(wei)置(zhi)(zhi)所示(shi)(shi)(shi)；補(bu)償給(gei)定量(liang)的(de)前(qian)(qian)饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)接(jie)(jie)在(zai)(zai)系(xi)(xi)(xi)統(tong)(tong)(tong)給(gei)定量(liang)之(zhi)后(hou)的(de)前(qian)(qian)向通道之(zhi)上，形(xing)(xing)成前(qian)(qian)饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)通路，如G3（S）位(wei)置(zhi)(zhi)所示(shi)(shi)(shi)，補(bu)償擾動量(liang)的(de)前(qian)(qian)饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)接(jie)(jie)在(zai)(zai)系(xi)(xi)(xi)統(tong)(tong)(tong)可測(ce)試的(de)振動量(liang)之(zhi)后(hou)，形(xing)(xing)成一條附加的(de)通道，如G4（S）位(wei)置(zhi)(zhi)所示(shi)(shi)(shi)。前(qian)(qian)饋(kui)校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)可以單獨作用與開(kai)環(huan)控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)，也(ye)(ye)可以作為(wei)(wei)反饋(kui)控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)的(de)附加校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)而組成復合校(xiao)(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)控制(zhi)(zhi)系(xi)(xi)(xi)統(tong)(tong)(tong)。

圖8  系統校正裝置(zhi)(zhi)位置(zhi)(zhi)示意(yi)圖

　　七、小結

　　開關電(dian)(dian)(dian)源系(xi)統通過控(kong)(kong)制電(dian)(dian)(dian)路(lu)對(dui)主功率(lv)(lv)電(dian)(dian)(dian)路(lu)的(de)(de)控(kong)(kong)制實現(xian)電(dian)(dian)(dian)能的(de)(de)變(bian)換。開關電(dian)(dian)(dian)源系(xi)統有多種(zhong)控(kong)(kong)制方(fang)式(shi)，而(er)控(kong)(kong)制方(fang)式(shi)的(de)(de)核心是校正方(fang)式(shi)。究竟選用哪種(zhong)控(kong)(kong)制方(fang)式(shi)，系(xi)統如何校正，取(qu)決(jue)于系(xi)統主功率(lv)(lv)電(dian)(dian)(dian)路(lu)的(de)(de)被控(kong)(kong)量的(de)(de)性(xing)質、抗擾動(dong)性(xing)要(yao)求(qiu)、技(ji)術實現(xian)的(de)(de)方(fang)便性(xing)、經濟性(xing)要(yao)求(qiu)、環境使(shi)用條(tiao)件等因素(su)。