什麼是柵極驅動器？

 

jiandanlaishuo，zhajiqudongqishiyigeyongyufangdalaiziweikongzhiqihuoqitalaiyuandedidianyahuodidianliudehuanchongdianlu。zaimouxieqingkuangxia
，liruqudongyongyushuzixinhaochuanshudeluojidianpingjingtiguanshi，shiyongweikongzhiqishuchubuhuisunhaiyingyongdexiaolv
、尺寸或熱性能。在高功率應用中


，微控製器輸出通常不適合用於驅動功率較大的晶體管。

 

 

但dan是shi為wei什shen麼me要yao使shi用yong微wei控kong製zhi器qi來lai驅qu動dong功gong率lv晶jing體ti管guan呢ne？為wei了le更geng好hao地di回hui答da這zhe個ge問wen題ti
，我wo們men來lai考kao慮lv一yi下xia大da型xing的de應ying用yong。開kai關guan電dian源yuan是shi幾ji乎hu每mei一yi個ge現xian代dai電dian氣qi係xi統tong的de核he心xin。任ren何he插cha到dao壁bi式shi插cha座zuo上shang的de設she備bei都dou可ke以yi利li用yong開kai關guan電dian源yuan來lai進jin行xing功gong率lv因yin數shu校xiao正zheng和he生sheng成cheng直zhi流liu電dian流liu軌gui。汽qi車che係xi統tong使shi用yong開kai關guan電dian源yuan來lai維wei持chi電dian池chi、madahechongdianqidengxitong。dianwangjichusheshiyaoqiugaoxiaolvdizhuanhuanzhiliutaiyangnengdianchibantigongdekaiguandianneng，congerjiangdiannengchuanshudaozhiliucunchuxitonghejiaoliudianwang。

 

由於應用中存在大量拓撲且複雜性日益升高，對於高功率晶體管陣列，現代開關電源通常使用微控製器或其他ASIC來協調其開關

，以滿足精確的開關計時要求。這可能會帶來挑戰，因為大多數微控製器輸出並沒有針對驅動功率晶體管進行優化。

 

高功率晶體管與模擬信號鏈或數字邏輯電路中的其他晶體管的特性幾乎完全不同。功率晶體管的擊穿電壓的分布範圍極大，從大約40伏到1,200伏fu甚shen至zhi更geng高gao。由you於yu需xu要yao實shi現xian較jiao高gao的de漏lou極ji電dian路lu和he較jiao低di的de導dao通tong損sun耗hao，漏lou源yuan電dian阻zu需xu要yao低di至zhi幾ji十shi毫hao歐ou姆mu甚shen至zhi更geng小xiao。與yu漏lou源yuan電dian阻zu成cheng反fan比bi的de柵zha極ji電dian容rong通tong常chang超chao過guo10,000pF。柵極驅動電壓和電流要求在很大程度上取決於晶體管結構和漏極電流額定值
，其常見值在8至30伏和1至5安培之間。高噪聲環境甚至可能需要雙極輸出驅動。

 

 

與(yu)頻(pin)率(lv)為(wei)幾(ji)十(shi)或(huo)幾(ji)百(bai)兆(zhao)赫(he)的(de)信(xin)號(hao)鏈(lian)或(huo)數(shu)字(zi)晶(jing)體(ti)管(guan)相(xiang)比(bi)，傳(chuan)統(tong)高(gao)功(gong)率(lv)晶(jing)體(ti)管(guan)的(de)頻(pin)率(lv)上(shang)限(xian)隻(zhi)有(you)幾(ji)百(bai)千(qian)赫(he)
，隨(sui)著(zhe)新(xin)技(ji)術(shu)的(de)出(chu)現(xian)，有(you)可(ke)能(neng)會(hui)將(jiang)該(gai)上(shang)限(xian)推(tui)高(gao)一(yi)個(ge)數(shu)量(liang)級(ji)。這(zhe)種(zhong)頻(pin)率(lv)限(xian)製(zhi)是(shi)由(you)於(yu)增(zeng)高(gao)的(de)柵(zha)極(ji)電(dian)容(rong)和(he)驅(qu)動(dong)電(dian)壓(ya)要(yao)求(qiu)造(zao)成(cheng)的(de)。電(dian)容(rong)器(qi)的(de)能(neng)量(liang)等(deng)於(yu)1/2乘以電容再乘以電壓的平方。柵極電容的充放電功耗等於電容器的能量乘以頻率的兩倍--一次充電
，一次放電。具有15納法柵極電容的功率晶體管在200千赫、12伏方波驅動條件下需要近半瓦的功耗。對於可傳輸3至5千瓦電力的轉換器，提高開關頻率所帶來的好處，比如減小磁體的尺寸和重量，有時要比幾瓦驅動損耗的成本更有價值。

 

 

zaijuedingjingtiguandequdongyaoqiudeyuansuzhong，haiyouyizhonggengweijishoudesunhaoyuan。zaizhajidianrongchongfangdianguochengzhong，kaiguanhuizaiquankaihequanguanzhuangtaizhijiancunzaiyigeguoduqi，cishikaiguanshanghuichuxiandianya
，qiehuiyoudianliuliuguokaiguan。youyutongshicunzaijiaogaodedianyahejiaogaodedianliu，yincizheleikaiguansunhaohuizaochengxiangdangdadegonghao，youshihuidadaojishiwa，yijijinyibudexiaolvjiangji。yinci
，tongguogengkuaididuizhajidianrongjinxingchongfangdianlaisuoduanguoduqidechixushijianshiyouhaochude。

 

如ru果guo輸shu出chu電dian壓ya甚shen至zhi高gao到dao足zu以yi使shi晶jing體ti管guan導dao通tong
，那na麼me大da多duo數shu微wei控kong製zhi器qi提ti供gong的de低di電dian流liu信xin號hao在zai驅qu動dong高gao功gong率lv晶jing體ti管guan時shi都dou會hui慢man得de令ling人ren發fa指zhi，效xiao率lv極ji低di。

 

 

現(xian)在(zai)我(wo)們(men)來(lai)回(hui)答(da)什(shen)麼(me)是(shi)柵(zha)極(ji)驅(qu)動(dong)器(qi)這(zhe)個(ge)問(wen)題(ti)，柵(zha)極(ji)驅(qu)動(dong)器(qi)是(shi)一(yi)個(ge)用(yong)於(yu)放(fang)大(da)來(lai)自(zi)微(wei)控(kong)製(zhi)器(qi)或(huo)其(qi)他(ta)來(lai)源(yuan)的(de)控(kong)製(zhi)信(xin)號(hao)，從(cong)而(er)使(shi)其(qi)適(shi)應(ying)半(ban)導(dao)體(ti)開(kai)關(guan)的(de)有(you)效(xiao)和(he)高(gao)效(xiao)運(yun)行(xing)的(de)電(dian)路(lu)。

 

有許多柵極驅動器都可以在承受高偏置電壓的情況下工作，例如高功率轉換器中使用的那些。

 

柵極驅動器分類與優點分析

 

廣義地說，這些柵極驅動器分為兩類：非隔離式柵極驅動器和隔離式柵極驅動器。大多數用於在高電壓下運行的非隔離式柵極驅動器都是半橋驅動器。

 

半橋驅動器旨在驅動以半橋配置堆疊在一起的功率晶體管。它們有兩個通道：低di側ce和he高gao側ce。低di側ce是shi一yi個ge相xiang當dang簡jian單dan的de緩huan衝chong器qi，通tong常chang與yu控kong製zhi輸shu入ru具ju有you相xiang同tong的de接jie地di點dian。而er高gao側ce則ze是shi經jing過guo精jing心xin設she計ji且qie以yi半ban橋qiao的de開kai關guan節jie點dian為wei基ji準zhun，從cong而er允yun許xu使shi用yong兩liang個geN溝道MOSFET或兩個IGBT。開kai關guan節jie點dian應ying該gai在zai高gao電dian壓ya總zong線xian和he電dian源yuan接jie地di之zhi間jian快kuai速su過guo渡du，從cong而er讓rang我wo們men有you機ji會hui以yi具ju有you成cheng本ben效xiao益yi的de方fang式shi利li用yong與yu為wei低di側ce供gong電dian時shi相xiang同tong的de電dian源yuan通tong過guo自zi舉ju電dian路lu為wei高gao側ce供gong電dian。為wei了le傳chuan達da輸shu出chu應ying為wei高gao電dian平ping還hai是shi低di電dian平ping，必bi須xu包bao含han一yi個ge高gao電dian壓ya電dian平ping轉zhuan換huan器qi，該gai轉zhuan換huan器qi的de泄xie漏lou電dian流liu通tong常chang較jiao小xiao
，隻zhi有you幾ji微wei安an或huo更geng小xiao。

 

 

zhezhongleixingdezhajiqudongqijuyouhenduojuxianxing。shouxian，yinweitazhengtidouzaitongyiguipianshang
，yinci，wufachaochuguidegongyijixian。daduoshufeigelishizhajiqudongqidegongzuodianyadoubuchaoguo700fu。dier
，dianpingzhuanhuanqibixuchengshougaodianyayunxingdeyali，qiebixuzaigaozaoshenghuanjingzhongchuandashuchuzhuangtai。yinci，weileshixianchongzudezaoshenglvbo
，dianpingzhuanhuanqitongchanghuitianjiayixiechuanboyanchi。ranhou，dicedequdongqiyouyaoyugaocequdongqidejiaochangyanchixiangpipei。disan，yongyuzaigaodianyaxiayunxingdefeigelishizhajiqudongqibugoulinghuo。xianzaicunzaixuduofuzadetuopu，tamenyaoqiuduogeshuchunenggouzhuanhuanzhikongzhigonggongduandianpingyishanghuoyixia。

 

zaixiandaizhajiqudongqizhongyuelaiyuechangjiandetexingshizaishuruheshuchudianluzhijianjichenglegeliceng。zhexieqijianjiangyigeguipianyongyukongzhixinhao，lingyigeyongyushuchuqudongxinhao，bingtongguojulihejueyuancailiaoduiqijinxingwuligeli。kongzhixinhaozaichuanshuguochengzhongketongguoduozhongfangshichuanguogeliceng
，danshi，yufeigelishizhajiqudongqibutongdeshi，gelicengkefangzhirenhexianzhudexieloudianliuconggelicengdeyiceliuxianglingyice。youyuyigeshuruluopiankeyuduogeshuchuluopiangeli，ershuchuluopianzhijianyoukeyibicigeli，yincishuchugonggongduankeyiziyoudicongshurugonggongduanhuoqitashuchugonggongduanxiangshangpianyi，zhizhidadaogelijishudejixian。

 

 

與yu具ju有you不bu靈ling活huo的de電dian平ping轉zhuan換huan器qi和he預yu定ding輸shu出chu角jiao色se的de非fei隔ge離li式shi柵zha極ji驅qu動dong器qi不bu同tong的de是shi，隔ge離li式shi柵zha極ji驅qu動dong器qi的de輸shu出chu可ke以yi以yi電dian路lu中zhong的de任ren何he節jie點dian為wei基ji準zhun
，且qie可ke以yi構gou造zao為wei單dan通tong道dao或huo雙shuang通tong道dao器qi件jian。隔ge離li技ji術shu的de極ji限xian遠yuan遠yuan高gao於yu非fei隔ge離li式shi柵zha極ji驅qu動dong器qi的de矽gui工gong藝yi限xian製zhi，可ke提ti供gong耐nai受shou力li高gao於yu5千伏的隔離層。除了提高電壓上限和靈活性之外，隔離式柵極驅動器還可以用於實現更快速、更geng穩wen健jian的de運yun行xing。使shi用yong隔ge離li的de原yuan因yin有you很hen多duo。許xu多duo應ying用yong都dou因yin為wei監jian管guan要yao求qiu而er需xu要yao使shi用yong隔ge離li式shi電dian源yuan，並bing且qie隔ge離li式shi柵zha極ji驅qu動dong器qi可ke以yi用yong來lai簡jian化hua係xi統tong結jie構gou。有you時shi，隔ge離li層ceng的de強qiang度du還hai可ke以yi用yong來lai增zeng強qiang係xi統tong抵di抗kang浪lang湧yong、雷擊和其他有可能損壞係統的異常事件的能力。

 

在其他情況下
，通過靈活地使用隔離層可以簡化拓撲的設計，從而無需再使用信號轉換器或電平轉換器，如反相降壓/升壓。即使是在並不嚴格要求進行隔離的傳統半橋應用中，隔離式柵極驅動器也可以憑借優異的傳播延遲、較高的驅動力和對高電壓瞬態的更出色承受力而勝過非隔離式柵極驅動器。

 

 

使用隔離式柵極驅動器的常用拓撲包括牽引逆變器、電機驅動器、sanxianggonglvyinshuxiaozhengdianluhechuanshiguangfunibianqi。zhexietuopudouzaijiaoliuhezhiliudianyuanzhijianzhuanhuan，zhijieyugaodianyazhiliuzongxianhedianjihuodianwangdengsanxiangxitongxianglian。

 

 

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