一、前言

　　開關電源系(xi)(xi)(xi)統(tong)是(shi)弱電(dian)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)強電(dian)的(de)(de)(de)系(xi)(xi)(xi)統(tong)。開(kai)關(guan)(guan)(guan)電(dian)源(yuan)系(xi)(xi)(xi)統(tong)主(zhu)要可以分為主(zhu)功率(lv)(lv)(lv)電(dian)路(lu)(lu)(lu)和(he)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)電(dian)路(lu)(lu)(lu)兩部(bu)分。主(zhu)功率(lv)(lv)(lv)電(dian)路(lu)(lu)(lu)是(shi)由變換(huan)(huan)器構成(cheng)。變換(huan)(huan)器是(shi)應用(yong)功率(lv)(lv)(lv)半(ban)(ban)導(dao)(dao)體(ti)器件，對(dui)(dui)電(dian)能(neng)進行(xing)變換(huan)(huan)的(de)(de)(de)裝置(zhi)，變換(huan)(huan)量(liang)包括電(dian)壓、電(dian)流、頻率(lv)(lv)(lv)和(he)波形(xing)等方面，以達(da)到電(dian)能(neng)更好符合(he)各種不同用(yong)電(dian)設備要求的(de)(de)(de)目的(de)(de)(de)。這是(shi)通過(guo)對(dui)(dui)功率(lv)(lv)(lv)半(ban)(ban)導(dao)(dao)體(ti)器件的(de)(de)(de)開(kai)關(guan)(guan)(guan)的(de)(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)來實現的(de)(de)(de)。因此主(zhu)功率(lv)(lv)(lv)電(dian)路(lu)(lu)(lu)是(shi)開(kai)關(guan)(guan)(guan)電(dian)源(yuan)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)中的(de)(de)(de)被控(kong)(kong)對(dui)(dui)象，而控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)功率(lv)(lv)(lv)半(ban)(ban)導(dao)(dao)體(ti)器件的(de)(de)(de)開(kai)關(guan)(guan)(guan)以實現既定的(de)(de)(de)性能(neng)是(shi)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)裝置(zhi)的(de)(de)(de)主(zhu)要工(gong)作。將被控(kong)(kong)對(dui)(dui)象和(he)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)裝置(zhi)按(an)照一定的(de)(de)(de)方式(shi)連接起來，組成(cheng)一個(ge)有機的(de)(de)(de)總體(ti)，就構成(cheng)開(kai)關(guan)(guan)(guan)電(dian)源(yuan)的(de)(de)(de)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)，這樣的(de)(de)(de)電(dian)路(lu)(lu)(lu)即為控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)電(dian)路(lu)(lu)(lu)。控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)的(de)(de)(de)工(gong)作方式(shi)有多種，其中最(zui)基本的(de)(de)(de)一種是(shi)基于反(fan)饋控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)原理的(de)(de)(de)閉(bi)環控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)。而大部(bu)分的(de)(de)(de)開(kai)關(guan)(guan)(guan)電(dian)源(yuan)控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)是(shi)閉(bi)環控(kong)(kong)制(zhi)(zhi)(zhi)(zhi)(zhi)系(xi)(xi)(xi)統(tong)。

　　二、閉環控制原理

　　通常，我(wo)們把被控(kong)(kong)量(liang)(liang)送回到控(kong)(kong)制(zhi)系(xi)統的輸(shu)入端，與參據(ju)量(liang)(liang)相比較產(chan)生誤差信(xin)號的過(guo)程，稱為(wei)反饋(kui)(kui)。若反饋(kui)(kui)的信(xin)號是與參據(ju)量(liang)(liang)相減，使得產(chan)生的偏差越來越小，稱為(wei)負反饋(kui)(kui)。由于引入了被控(kong)(kong)量(liang)(liang)的反饋(kui)(kui)信(xin)息，整個控(kong)(kong)制(zhi)過(guo)程成為(wei)閉合的，因此也稱閉環(huan)控(kong)(kong)制(zhi)，如圖1所(suo)示(shi)。

圖1  反饋控制框圖

　　三、基本組成

　　控制裝(zhuang)置是由具(ju)有(you)(you)一(yi)定職能的各種基(ji)本元(yuan)器件組(zu)成(cheng)。系統的元(yuan)器件按照(zhao)職能分類主要有(you)(you)以(yi)下幾種：

　　測(ce)量單(dan)元：其(qi)職(zhi)能是檢測(ce)被(bei)控(kong)制的(de)(de)物理量。這個(ge)被(bei)控(kong)量一(yi)般為(wei)主功(gong)率(lv)電(dian)路的(de)(de)輸出電(dian)壓、主功(gong)率(lv)電(dian)路的(de)(de)輸入電(dian)流等。

　　給(gei)定(ding)單(dan)元(yuan)：其職能是給(gei)出與期(qi)望(wang)的(de)被(bei)控量相對應的(de)參據量，即(ji)給(gei)定(ding)量。在開關電源系統中，給(gei)定(ding)量一般(ban)為直流常量或(huo)者是交流正弦量。

　　比較單(dan)元：其(qi)職(zhi)能是將檢測到的被控制量(liang)的實際值與參據量(liang)進行比較，求(qiu)出他們之(zhi)間(jian)的偏差。

　　校正單(dan)(dan)元：即(ji)補償單(dan)(dan)元，用串(chuan)聯方式(shi)或者(zhe)反饋方式(shi)（并聯方式(shi)）等方式(shi)連接在系(xi)統中，以(yi)(yi)改善系(xi)統的(de)(de)性(xing)能。這(zhe)(zhe)個補償網(wang)絡(luo)是控(kong)制系(xi)統的(de)(de)核(he)心部分，是決定控(kong)制系(xi)統性(xing)能的(de)(de)關鍵部分。可以(yi)(yi)通(tong)過由(you)電阻、電容(rong)組(zu)成的(de)(de)無源(yuan)或有源(yuan)網(wang)絡(luo)實現，也可以(yi)(yi)通(tong)過MCU、DSP這(zhe)(zhe)些數字器件(jian)輔助實現。

　　四、外作用類型

　　一般(ban)加在開關(guan)電(dian)(dian)源系統(tong)上的(de)外作(zuo)用(yong)(yong)(yong)有兩種(zhong)類型：一種(zhong)是(shi)(shi)有用(yong)(yong)(yong)輸(shu)入(ru)，它決定(ding)系統(tong)被控量(liang)的(de)變化規律，比(bi)如給定(ding)量(liang)；一種(zhong)是(shi)(shi)系統(tong)不希望有的(de)外作(zuo)用(yong)(yong)(yong)，即擾動(dong)(dong)(dong)，它破壞有用(yong)(yong)(yong)輸(shu)入(ru)對(dui)系統(tong)的(de)控制(zhi)。在實際系統(tong)中(zhong)，擾動(dong)(dong)(dong)是(shi)(shi)不可避(bi)免(mian)的(de)。這樣的(de)擾動(dong)(dong)(dong)包(bao)括(kuo)：主(zhu)功率電(dian)(dian)路輸(shu)入(ru)電(dian)(dian)壓的(de)波(bo)動(dong)(dong)(dong)，主(zhu)功率電(dian)(dian)路輸(shu)出電(dian)(dian)流(liu)的(de)波(bo)動(dong)(dong)(dong)或者負載的(de)波(bo)動(dong)(dong)(dong)，元器件參數的(de)溫度(du)漂移(yi)等。

      五、基本控(kong)制方(fang)式

　　反(fan)饋(kui)控制(zhi)是(shi)系(xi)統最基本的(de)控制(zhi)方(fang)式(shi)(shi)，也是(shi)應用最廣(guang)泛(fan)的(de)一種控制(zhi)方(fang)式(shi)(shi)。此外，還(huan)有開環控制(zhi)方(fang)式(shi)(shi)和復合控制(zhi)方(fang)式(shi)(shi)，它們都有著各自的(de)特點和不同的(de)應用場合。

　　（1）反饋控制(zhi)方式

　　如(ru)前面所提及，反饋控(kong)制(zhi)方式是(shi)按照偏(pian)差進(jin)行(xing)控(kong)制(zhi)的(de)(de)，其特(te)點是(shi)不(bu)論(lun)什么原因使被(bei)控(kong)量偏(pian)離期(qi)望值而出現偏(pian)差時，必定會產(chan)生一(yi)個相應的(de)(de)控(kong)制(zhi)作用去減小(xiao)或消除這個偏(pian)差，使被(bei)控(kong)量與(yu)期(qi)望值趨于一(yi)致。可見，按照反饋控(kong)制(zhi)方式設計的(de)(de)控(kong)制(zhi)系(xi)統，具有抑制(zhi)任何內(nei)、外擾動(dong)對被(bei)控(kong)量產(chan)生影響的(de)(de)能力，有較高的(de)(de)穩態精度。

　　如(ru)圖2所示(shi)為電壓(ya)型(xing)控制Boost變(bian)換器控制框(kuang)圖，電壓(ya)反饋控制技術(shu)是開關電源系(xi)統中經典的反饋控制方法。這(zhe)是60年代后期開關穩壓(ya)電源剛剛開始發展就采用的第一(yi)種控制方法，該方法與一(yi)些(xie)必要(yao)的過電流保護電路相結合，至(zhi)今(jin)仍然被廣(guang)泛(fan)的應用。

圖2  電壓(ya)型控(kong)制 Boost 變換器控(kong)制框(kuang)圖

　　（2）開環控(kong)制方式

　　開環控(kong)(kong)(kong)制(zhi)(zhi)方(fang)(fang)(fang)式(shi)是指被控(kong)(kong)(kong)裝(zhuang)置與被控(kong)(kong)(kong)對象之間只(zhi)有順向作用而(er)沒有反向聯系(xi)的(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)過程。按這種控(kong)(kong)(kong)制(zhi)(zhi)方(fang)(fang)(fang)式(shi)組成(cheng)的(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)系(xi)統(tong)稱為開環控(kong)(kong)(kong)制(zhi)(zhi)系(xi)統(tong)，其特點是系(xi)統(tong)的(de)(de)輸(shu)出(chu)量(liang)不(bu)會對系(xi)統(tong)的(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)作用發生(sheng)影響。這種控(kong)(kong)(kong)制(zhi)(zhi)方(fang)(fang)(fang)式(shi)也(ye)稱為前饋控(kong)(kong)(kong)制(zhi)(zhi)、順饋控(kong)(kong)(kong)制(zhi)(zhi)。開環控(kong)(kong)(kong)制(zhi)(zhi)系(xi)統(tong)可(ke)以由按給(gei)定量(liang)控(kong)(kong)(kong)制(zhi)(zhi)的(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)方(fang)(fang)(fang)式(shi)組成(cheng)，也(ye)可(ke)以由按擾動(dong)控(kong)(kong)(kong)制(zhi)(zhi)的(de)(de)控(kong)(kong)(kong)制(zhi)(zhi)方(fang)(fang)(fang)式(shi)組成(cheng)。

　　按給定量(liang)控(kong)制(zhi)(zhi)(zhi)的(de)(de)開環控(kong)制(zhi)(zhi)(zhi)系(xi)統，其(qi)控(kong)制(zhi)(zhi)(zhi)作用直接由(you)控(kong)制(zhi)(zhi)(zhi)系(xi)統的(de)(de)輸入量(liang)產生，給定一(yi)個(ge)輸入量(liang)，就有一(yi)個(ge)輸出量(liang)與之相對應，控(kong)制(zhi)(zhi)(zhi)精度完全取決于控(kong)制(zhi)(zhi)(zhi)電(dian)路(lu)(lu)所(suo)用的(de)(de)元(yuan)器(qi)件以及主功(gong)率電(dian)路(lu)(lu)的(de)(de)特性，如(ru)圖(tu)3所(suo)示。這種控(kong)制(zhi)(zhi)(zhi)方式沒(mei)有自動(dong)(dong)修(xiu)正偏差的(de)(de)能(neng)力，抗擾動(dong)(dong)能(neng)力差。但由(you)于其(qi)結構簡單、調(diao)整方便、成本低(di)，在精度要求不高或擾動(dong)(dong)影響較小的(de)(de)情(qing)況下，這種控(kong)制(zhi)(zhi)(zhi)方式還是(shi)有一(yi)定的(de)(de)實用價值。

圖(tu)3  按給定量(liang)控制的(de)開(kai)環控制系統

如圖4所示的(de)采用電容的(de)開(kai)關(guan)功率(lv)變(bian)換器，一(yi)般為(wei)多級變(bian)換電路中的(de)其中一(yi)級，通常采用開(kai)環控(kong)制，效(xiao)率(lv)和功率(lv)密度較(jiao)高，容易(yi)實現開(kai)關(guan)，具有廣泛的(de)應用前(qian)景。

圖(tu)4  開環控制的(de)開關電容功率變換器

　　按(an)擾(rao)動控制(zhi)的(de)開環控制(zhi)系(xi)統，是(shi)利用(yong)可(ke)測量(liang)(liang)(liang)的(de)擾(rao)動量(liang)(liang)(liang)，產生一(yi)種補(bu)償作用(yong)，以(yi)減少或抵消擾(rao)動對輸出量(liang)(liang)(liang)的(de)影(ying)響，如圖(tu)5所示(shi)。這(zhe)種控制(zhi)方式直接(jie)從擾(rao)動取得信息，并據此改變被控量(liang)(liang)(liang)，因此其(qi)抗擾(rao)動性(xing)好，控制(zhi)精度(du)也較高，但它只適用(yong)于擾(rao)動是(shi)可(ke)以(yi)測量(liang)(liang)(liang)的(de)場合，而且一(yi)個(ge)補(bu)償裝置只能補(bu)償一(yi)個(ge)擾(rao)動因素，對其(qi)余擾(rao)動均不(bu)起補(bu)償作用(yong)。

圖5  按擾(rao)動控制的開環控制系統

　　如圖(tu)6所示為單(dan)(dan)周期(qi)控(kong)(kong)(kong)制(zhi)Buck變換器控(kong)(kong)(kong)制(zhi)框(kuang)圖(tu)，單(dan)(dan)周期(qi)控(kong)(kong)(kong)制(zhi)技術實際上就(jiu)是一(yi)種按擾(rao)動(dong)控(kong)(kong)(kong)制(zhi)的(de)(de)開環控(kong)(kong)(kong)制(zhi)系統。它將主功(gong)率(lv)電路(lu)的(de)(de)輸入(ru)電壓(ya)引(yin)入(ru)控(kong)(kong)(kong)制(zhi)，隨著輸入(ru)電壓(ya)的(de)(de)變化(hua)，得到不同的(de)(de)占空度，使(shi)得主功(gong)率(lv)電路(lu)的(de)(de)輸出電壓(ya)跟(gen)隨給(gei)定量。理論(lun)上這種控(kong)(kong)(kong)制(zhi)技術完全抵制(zhi)了主功(gong)率(lv)電路(lu)的(de)(de)輸出電壓(ya)擾(rao)動(dong)，但(dan)是對負載的(de)(de)擾(rao)動(dong)卻(que)無(wu)能為力。

圖(tu)6  單周期(qi)控制 Buck 變(bian)換器控制框圖(tu)

 （3）復合控(kong)制方式

　　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(suo)(suo)示為(wei)(wei)(wei)具有輸(shu)(shu)入(ru)(ru)電(dian)壓(ya)(ya)前饋的(de)(de)(de)平(ping)均(jun)電(dian)流(liu)控(kong)(kong)(kong)(kong)(kong)(kong)制Boost變換(huan)器(qi)的(de)(de)(de)PFC控(kong)(kong)(kong)(kong)(kong)(kong)制框圖，這種(zhong)控(kong)(kong)(kong)(kong)(kong)(kong)制方(fang)法(fa)(fa)為(wei)(wei)(wei)雙(shuang)環(huan)(huan)反饋的(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)制方(fang)法(fa)(fa)，外環(huan)(huan)為(wei)(wei)(wei)母線電(dian)壓(ya)(ya)平(ping)均(jun)值控(kong)(kong)(kong)(kong)(kong)(kong)制環(huan)(huan)，內環(huan)(huan)為(wei)(wei)(wei)輸(shu)(shu)入(ru)(ru)電(dian)流(liu)控(kong)(kong)(kong)(kong)(kong)(kong)制環(huan)(huan)。該控(kong)(kong)(kong)(kong)(kong)(kong)制方(fang)法(fa)(fa)將輸(shu)(shu)出(chu)(chu)電(dian)壓(ya)(ya)的(de)(de)(de)平(ping)均(jun)值作(zuo)(zuo)為(wei)(wei)(wei)反饋與基準比(bi)較，產(chan)生的(de)(de)(de)誤差信號經由電(dian)壓(ya)(ya)補(bu)(bu)償(chang)器(qi)進(jin)行調(diao)節。產(chan)生的(de)(de)(de)信號與輸(shu)(shu)入(ru)(ru)電(dian)壓(ya)(ya)有效值一起，控(kong)(kong)(kong)(kong)(kong)(kong)制正弦波(bo)(bo)基準的(de)(de)(de)幅值。再(zai)將輸(shu)(shu)入(ru)(ru)電(dian)流(liu)作(zuo)(zuo)為(wei)(wei)(wei)反饋與正弦波(bo)(bo)基準進(jin)行比(bi)較，產(chan)生的(de)(de)(de)誤差信號經由電(dian)流(liu)補(bu)(bu)償(chang)器(qi)進(jin)行調(diao)節產(chan)生調(diao)制信號，再(zai)將該調(diao)制信號與載(zai)波(bo)(bo)比(bi)較得到(dao)控(kong)(kong)(kong)(kong)(kong)(kong)制信號，得到(dao)所(suo)(suo)需的(de)(de)(de)控(kong)(kong)(kong)(kong)(kong)(kong)制信號，外環(huan)(huan)的(de)(de)(de)作(zuo)(zuo)用，主(zhu)(zhu)要(yao)控(kong)(kong)(kong)(kong)(kong)(kong)制輸(shu)(shu)出(chu)(chu)電(dian)壓(ya)(ya)，內環(huan)(huan)主(zhu)(zhu)要(yao)控(kong)(kong)(kong)(kong)(kong)(kong)制輸(shu)(shu)入(ru)(ru)電(dian)流(liu)的(de)(de)(de)波(bo)(bo)形，保證輸(shu)(shu)入(ru)(ru)電(dian)流(liu)的(de)(de)(de)正弦度。引入(ru)(ru)了(le)輸(shu)(shu)入(ru)(ru)電(dian)壓(ya)(ya)前饋，克服輸(shu)(shu)入(ru)(ru)電(dian)壓(ya)(ya)擾(rao)動(dong)對輸(shu)(shu)出(chu)(chu)電(dian)壓(ya)(ya)的(de)(de)(de)影響(xiang)。

圖7  具有輸入電(dian)壓前饋(kui)的平(ping)均電(dian)流控制 Boost 變換器的PFC

　　六、校正方式

　　對控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)的(de)(de)(de)(de)要求(qiu)，通(tong)(tong)常以(yi)性能指標(biao)的(de)(de)(de)(de)形(xing)(xing)式給(gei)(gei)出。而(er)為(wei)(wei)(wei)了(le)使(shi)系(xi)(xi)(xi)(xi)統(tong)(tong)獲得(de)滿意的(de)(de)(de)(de)性能，必須對控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)進行設(she)計和校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)，也就是(shi)在(zai)系(xi)(xi)(xi)(xi)統(tong)(tong)中適當的(de)(de)(de)(de)位(wei)置(zhi)(zhi)(zhi)(zhi)加(jia)進適當的(de)(de)(de)(de)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)。校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)彌補(bu)了(le)原(yuan)系(xi)(xi)(xi)(xi)統(tong)(tong)的(de)(de)(de)(de)性能缺陷。按照校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)在(zai)開關電源系(xi)(xi)(xi)(xi)統(tong)(tong)中的(de)(de)(de)(de)連接(jie)(jie)方(fang)式，控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)的(de)(de)(de)(de)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)方(fang)式可(ke)(ke)以(yi)分為(wei)(wei)(wei)串(chuan)聯(lian)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、反饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、前(qian)饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)、復(fu)合(he)(he)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)等。如圖8所(suo)(suo)示(shi)為(wei)(wei)(wei)系(xi)(xi)(xi)(xi)統(tong)(tong)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)位(wei)置(zhi)(zhi)(zhi)(zhi)示(shi)意圖，G（S）為(wei)(wei)(wei)被(bei)控(kong)對象（主功率電路）；串(chuan)聯(lian)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)一般(ban)連接(jie)(jie)在(zai)G（S）之(zhi)(zhi)(zhi)(zhi)前(qian)，串(chuan)接(jie)(jie)與系(xi)(xi)(xi)(xi)統(tong)(tong)前(qian)向通(tong)(tong)道(dao)之(zhi)(zhi)(zhi)(zhi)中，如G1（S）益(yi)所(suo)(suo)示(shi)；反饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)連接(jie)(jie)在(zai)系(xi)(xi)(xi)(xi)統(tong)(tong)局部反饋(kui)(kui)通(tong)(tong)路之(zhi)(zhi)(zhi)(zhi)中，如G2（S）位(wei)置(zhi)(zhi)(zhi)(zhi)所(suo)(suo)示(shi)；補(bu)償給(gei)(gei)定量的(de)(de)(de)(de)前(qian)饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)接(jie)(jie)在(zai)系(xi)(xi)(xi)(xi)統(tong)(tong)給(gei)(gei)定量之(zhi)(zhi)(zhi)(zhi)后的(de)(de)(de)(de)前(qian)向通(tong)(tong)道(dao)之(zhi)(zhi)(zhi)(zhi)上，形(xing)(xing)成前(qian)饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)通(tong)(tong)路，如G3（S）位(wei)置(zhi)(zhi)(zhi)(zhi)所(suo)(suo)示(shi)，補(bu)償擾動量的(de)(de)(de)(de)前(qian)饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)接(jie)(jie)在(zai)系(xi)(xi)(xi)(xi)統(tong)(tong)可(ke)(ke)測(ce)試的(de)(de)(de)(de)振動量之(zhi)(zhi)(zhi)(zhi)后，形(xing)(xing)成一條附加(jia)的(de)(de)(de)(de)通(tong)(tong)道(dao)，如G4（S）位(wei)置(zhi)(zhi)(zhi)(zhi)所(suo)(suo)示(shi)。前(qian)饋(kui)(kui)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)裝(zhuang)(zhuang)(zhuang)(zhuang)置(zhi)(zhi)(zhi)(zhi)可(ke)(ke)以(yi)單獨(du)作用與開環控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)，也可(ke)(ke)以(yi)作為(wei)(wei)(wei)反饋(kui)(kui)控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)的(de)(de)(de)(de)附加(jia)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)而(er)組成復(fu)合(he)(he)校(xiao)(xiao)(xiao)(xiao)正(zheng)(zheng)(zheng)控(kong)制系(xi)(xi)(xi)(xi)統(tong)(tong)。

圖8  系統校正裝置位置示(shi)意(yi)圖

　　七、小結

　　開關(guan)(guan)電(dian)(dian)(dian)源系(xi)統(tong)通(tong)過控(kong)制(zhi)(zhi)電(dian)(dian)(dian)路對主功(gong)率電(dian)(dian)(dian)路的(de)(de)控(kong)制(zhi)(zhi)實現(xian)電(dian)(dian)(dian)能的(de)(de)變換。開關(guan)(guan)電(dian)(dian)(dian)源系(xi)統(tong)有多種控(kong)制(zhi)(zhi)方式(shi)，而控(kong)制(zhi)(zhi)方式(shi)的(de)(de)核(he)心是校正(zheng)方式(shi)。究(jiu)竟(jing)選用哪種控(kong)制(zhi)(zhi)方式(shi)，系(xi)統(tong)如何校正(zheng)，取決于系(xi)統(tong)主功(gong)率電(dian)(dian)(dian)路的(de)(de)被控(kong)量的(de)(de)性(xing)質、抗擾動性(xing)要求、技術實現(xian)的(de)(de)方便性(xing)、經濟(ji)性(xing)要求、環境使用條件等(deng)因素(su)。