河東電機是一種將電(dian)能轉換(huan)為機械(xie)能的(de)裝置(zhi)。大多(duo)數電(dian)機通過電(dian)流在導線繞組中與磁場的(de)相互作用(yong)(yong)來產生扭矩(ju),作用(yong)(yong)在電(dian)機軸上形(xing)成力。電(dian)機應用(yong)(yong)場景(jing)眾多(duo),在消(xiao)費市場、工業、車載等都有應用(yong)(yong)。
下面我們首先(xian)(xian)通過復盤(pan)海外高端電(dian)機(ji)(ji)廠商的發(fa)展(zhan)歷(li)程,了解率先(xian)(xian)布(bu)局高壁壘/新興領域+掌握(wo)一體化技術、掌握(wo)先(xian)(xian)發(fa)優勢是維持電(dian)機(ji)(ji)企業高利潤的關鍵。當前電(dian)機(ji)(ji)行業競爭激烈(lie),人(ren)形機(ji)(ji)器人(ren)蓄勢待發(fa),驅動(dong)電(dian)機(ji)(ji)廠商抓住(zhu)技術更新迭代(dai)的機(ji)(ji)遇(yu),及時布(bu)局伺服電(dian)機(ji)(ji)、空心杯電(dian)機(ji)(ji)、無框電(dian)機(ji)(ji)等,真正實現國產替(ti)代(dai)沖出重圍,在下一階(jie)段競爭中搶占先(xian)(xian)機(ji)(ji)。
01電機行業概述
1.電機定義及組成
電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)是一種(zhong)(zhong)利(li)用電(dian)(dian)與(yu)磁相互作用從而實現能(neng)(neng)量轉換與(yu)傳(chuan)遞的(de)機(ji)(ji)(ji)(ji)(ji)械電(dian)(dian)磁裝置。廣(guang)(guang)義的(de)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)包括電(dian)(dian)動(dong)機(ji)(ji)(ji)(ji)(ji)、發(fa)(fa)(fa)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)和(he)特種(zhong)(zhong)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)。電(dian)(dian)動(dong)機(ji)(ji)(ji)(ji)(ji)從電(dian)(dian)系(xi)統吸收電(dian)(dian)能(neng)(neng),向機(ji)(ji)(ji)(ji)(ji)械系(xi)統輸(shu)出(chu)機(ji)(ji)(ji)(ji)(ji)械能(neng)(neng),各類(lei)型的(de)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)廣(guang)(guang)泛應用于我國經(jing)濟(ji)生產各部門(men)(men)以及家用電(dian)(dian)器(qi)中(zhong),主(zhu)要(yao)作為驅(qu)動(dong)各種(zhong)(zhong)機(ji)(ji)(ji)(ji)(ji)械設(she)備的(de)動(dong)力(li);發(fa)(fa)(fa)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)從機(ji)(ji)(ji)(ji)(ji)械系(xi)統吸收機(ji)(ji)(ji)(ji)(ji)械能(neng)(neng),向電(dian)(dian)系(xi)統輸(shu)出(chu)電(dian)(dian)能(neng)(neng),發(fa)(fa)(fa)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)和(he)相關(guan)設(she)備的(de)技術進(jin)步,使人們能(neng)(neng)夠利(li)用熱能(neng)(neng)、水能(neng)(neng)、核能(neng)(neng)以及風能(neng)(neng)、太(tai)陽能(neng)(neng)、生物(wu)質(zhi)能(neng)(neng)等(deng)能(neng)(neng)源發(fa)(fa)(fa)電(dian)(dian),向國民經(jing)濟(ji)各部門(men)(men)和(he)廣(guang)(guang)大城鄉居民提(ti)供所需(xu)電(dian)(dian)能(neng)(neng);特種(zhong)(zhong)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)主(zhu)要(yao)是指(zhi)使用環境、生產工(gong)藝、技術標準等(deng)比較(jiao)特殊而區別于普通電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)的(de)電(dian)(dian)機(ji)(ji)(ji)(ji)(ji)。
從結(jie)構(gou)上來看,不同(tong)類型電(dian)機(ji)結(jie)構(gou)雖然(ran)不同(tong),但一般(ban)都(dou)是由三大部(bu)分(fen)組成,即固(gu)(gu)定(ding)(ding)部(bu)分(fen)、轉(zhuan)(zhuan)動部(bu)分(fen)和(he)輔助部(bu)分(fen)。固(gu)(gu)定(ding)(ding)部(bu)分(fen)主(zhu)要由定(ding)(ding)子(zi)機(ji)座、機(ji)架(jia)、定(ding)(ding)子(zi)鐵心、定(ding)(ding)子(zi)繞組、端(duan)蓋及(ji)底板等(deng)導磁(ci)、導電(dian)和(he)支撐固(gu)(gu)定(ding)(ding)等(deng)結(jie)構(gou)部(bu)件(jian)組合;電(dian)機(ji)的轉(zhuan)(zhuan)動部(bu)分(fen)包括轉(zhuan)(zhuan)軸(zhou)、轉(zhuan)(zhuan)子(zi)鐵心、轉(zhuan)(zhuan)子(zi)支架(jia)、轉(zhuan)(zhuan)子(zi)繞組、集電(dian)環、換向器和(he)風扇(shan)等(deng)部(bu)件(jian);輔助部(bu)分(fen)包括軸(zhou)承、電(dian)刷和(he)冷卻器等(deng)。
2.電機分類
電機(ji)(ji)有多(duo)種分類方(fang)式,按照應用領域分為動力電機(ji)(ji)和控制電機(ji)(ji);按照電源類型分為直流電機(ji)(ji)和交流電機(ji)(ji)。
(1)按照應(ying)用領(ling)域分為動力電(dian)機(ji)和控制電(dian)機(ji)
動力電(dian)(dian)機(ji)輸出(chu)(chu)功(gong)率(lv)較大,注重(zhong)電(dian)(dian)機(ji)的驅動、運行及制(zhi)動性(xing)能,主(zhu)(zhu)要應(ying)用于(yu)汽車、家(jia)電(dian)(dian)、小(xiao)型(xing)機(ji)床等(deng)領域。控(kong)制(zhi)電(dian)(dian)機(ji)側(ce)重(zhong)電(dian)(dian)機(ji)輸出(chu)(chu)量(liang)的幅頻(pin)特性(xing)、相頻(pin)特性(xing)及輸出(chu)(chu)特性(xing)的精(jing)度(du)、靈敏度(du)、穩定(ding)性(xing)、線(xian)性(xing)度(du)等(deng)指標,精(jing)度(du)高、響應(ying)速度(du)快(kuai),主(zhu)(zhu)要在自動控(kong)制(zhi)系(xi)統中承(cheng)擔執行、檢測和解算功(gong)能。
1)動力電機
按照運動(dong)(dong)方式(shi)進一(yi)步分(fen)為(wei)旋轉(zhuan)電(dian)(dian)(dian)(dian)機和直(zhi)線(xian)(xian)電(dian)(dian)(dian)(dian)機。直(zhi)線(xian)(xian)電(dian)(dian)(dian)(dian)機可看作(zuo)由旋轉(zhuan)電(dian)(dian)(dian)(dian)機展平而得,其定子叫初級、轉(zhuan)子叫次級,其優(you)勢在于(yu)可以直(zhi)接將電(dian)(dian)(dian)(dian)能(neng)轉(zhuan)換為(wei)直(zhi)線(xian)(xian)運動(dong)(dong)的機械能(neng),而無(wu)(wu)需再借助中間轉(zhuan)換裝(zhuang)置。常(chang)見的直(zhi)線(xian)(xian)電(dian)(dian)(dian)(dian)機可分(fen)為(wei)U型槽式(shi)、平板式(shi)和管式(shi)。其主要應用(yong)于(yu)自動(dong)(dong)控(kong)制系統(tong)、短距(ju)離需要巨(ju)大直(zhi)線(xian)(xian)運動(dong)(dong)能(neng)的裝(zhuang)置或作(zuo)為(wei)長期連續運行的驅(qu)動(dong)(dong)電(dian)(dian)(dian)(dian)機,例如用(yong)于(yu)磁懸浮列(lie)車(che)以及無(wu)(wu)鋼絲繩電(dian)(dian)(dian)(dian)梯(ti)的驅(qu)動(dong)(dong)。
2)控制電機
按照控制方(fang)式進一(yi)步分為步進電(dian)機、伺服(fu)電(dian)機、力矩電(dian)機。
步進(jin)電(dian)(dian)機是一種把電(dian)(dian)脈沖信(xin)號轉(zhuan)換成角位移的(de)電(dian)(dian)動(dong)機,每(mei)輸入(ru)一個脈沖信(xin)號,步進(jin)電(dian)(dian)機就按照設(she)定(ding)的(de)方向轉(zhuan)動(dong)一個固(gu)定(ding)的(de)角度(du)。其(qi)結構簡單但效率和精度(du)較(jiao)低,多用(yong)于辦公自動(dong)化、通信(xin)設(she)備(bei)、印刷設(she)備(bei)等領域。
伺服電(dian)(dian)機(ji)(ji)相較于步進電(dian)(dian)機(ji)(ji)增加(jia)了編碼器(qi)(qi)與(yu)反(fan)饋(kui)機(ji)(ji)制(zhi)(zhi),使得驅動器(qi)(qi)可以(yi)根據目標值與(yu)編碼器(qi)(qi)的(de)(de)反(fan)饋(kui)信號之間的(de)(de)差異(yi)來調整轉(zhuan)子轉(zhuan)動的(de)(de)角度(du)(du),從而可實(shi)現更精(jing)密的(de)(de)控制(zhi)(zhi),主要適用于半導體、光伏、鋰電(dian)(dian)、工(gong)業自動化、機(ji)(ji)器(qi)(qi)人等(deng)對于控制(zhi)(zhi)精(jing)度(du)(du)、速度(du)(du)響應、過載(zai)能力及穩(wen)定性要求(qiu)高(gao)的(de)(de)領(ling)域。空心(xin)杯電(dian)(dian)機(ji)(ji)是一種(zhong)特殊的(de)(de)伺服電(dian)(dian)機(ji)(ji),采用無鐵芯(xin)轉(zhuan)子,呈空心(xin)的(de)(de)杯狀(zhuang)結構,內部環繞著繞組和磁鐵。
力矩(ju)(ju)電(dian)機(ji)(ji)是(shi)以扭矩(ju)(ju)為(wei)控制方向的(de)電(dian)機(ji)(ji),采用開環(huan)控制。當(dang)負載轉(zhuan)(zhuan)矩(ju)(ju)增大時能自(zi)動降低轉(zhuan)(zhuan)速(su)(su),同時加大輸出轉(zhuan)(zhuan)矩(ju)(ju),當(dang)負載轉(zhuan)(zhuan)矩(ju)(ju)為(wei)一定(ding)值時改變電(dian)機(ji)(ji)端電(dian)壓便可調速(su)(su)。在電(dian)動機(ji)(ji)低速(su)(su)甚至堵轉(zhuan)(zhuan)(轉(zhuan)(zhuan)子無法(fa)轉(zhuan)(zhuan)動)時仍(reng)能持(chi)續運轉(zhuan)(zhuan),不會(hui)造(zao)成電(dian)動機(ji)(ji)的(de)損壞,并提供穩定(ding)的(de)力矩(ju)(ju)給負載,具有低轉(zhuan)(zhuan)速(su)(su)、大扭矩(ju)(ju)、過載能力強、響應快(kuai)、特性(xing)線(xian)性(xing)度好(hao)等優點。力矩(ju)(ju)電(dian)機(ji)(ji)分為(wei)有框力矩(ju)(ju)電(dian)機(ji)(ji)和無框力矩(ju)(ju)電(dian)機(ji)(ji)。
(2)按(an)照電源類型分為直流電機和交(jiao)流電機
直(zhi)(zhi)流電(dian)機(ji)由直(zhi)(zhi)流電(dian)源驅(qu)動,交流電(dian)機(ji)由交流電(dian)源驅(qu)動。直(zhi)(zhi)流電(dian)機(ji)調(diao)(diao)速性能好、啟(qi)動力矩大,適用(yong)于在(zai)重負載下啟(qi)動或需要(yao)均(jun)勻(yun)調(diao)(diao)節轉速的機(ji)械(xie)。交流電(dian)機(ji)效(xiao)率(lv)高(gao)、噪音(yin)低,常用(yong)于家(jia)用(yong)電(dian)器中。
1)直流電機
按照電刷的有(you)(you)無進一步分為有(you)(you)刷電機(ji)與無刷電機(ji)。對于直流電機(ji),為使轉(zhuan)子(zi)轉(zhuan)動需要不斷改變電流方向。
有刷電(dian)機(ji)采用機(ji)械換向,內部(bu)的(de)(de)電(dian)樞和換向器(qi)一起旋轉,而(er)外部(bu)的(de)(de)磁極和電(dian)刷都(dou)不(bu)動(dong)(dong)。通(tong)過換向器(qi)與(yu)電(dian)刷的(de)(de)交替接(jie)觸,電(dian)機(ji)運行時(shi)電(dian)流的(de)(de)方向就會不(bu)斷改(gai)變(bian),從而(er)改(gai)變(bian)電(dian)機(ji)的(de)(de)運動(dong)(dong)方向。其優勢在于(yu)啟動(dong)(dong)快速、制(zhi)動(dong)(dong)及時(shi)、調速平穩,并且(qie)啟動(dong)(dong)電(dian)流大(da)、在低(di)速時(shi)扭矩(ju)大(da),因而(er)能(neng)帶(dai)很重的(de)(de)負荷(he),常用在電(dian)鉆等日常電(dian)動(dong)(dong)工具(ju)中(zhong)。但由于(yu)換向器(qi)與(yu)電(dian)刷之間存在摩擦,因而(er)電(dian)刷易損耗、壽命短,并且(qie)效(xiao)率較(jiao)低(di)。
無(wu)刷(shua)(shua)電(dian)機(ji)采用(yong)電(dian)氣換向,以霍爾元件(jian)等電(dian)子換向器替(ti)代了機(ji)械(xie)電(dian)刷(shua)(shua)裝(zhuang)置,其線圈(quan)(quan)不(bu)動而磁(ci)(ci)(ci)極(ji)(ji)旋轉(zhuan)。其原(yuan)理是通(tong)過霍爾元件(jian)感知永磁(ci)(ci)(ci)體磁(ci)(ci)(ci)極(ji)(ji)的位置,從而適時切(qie)換線圈(quan)(quan)中電(dian)流(liu)的方向,以產(chan)生正(zheng)確方向的磁(ci)(ci)(ci)力來驅動電(dian)機(ji)。無(wu)刷(shua)(shua)電(dian)機(ji)的優(you)勢(shi)在(zai)于故(gu)障(zhang)率(lv)低、使(shi)用(yong)壽(shou)命長、運(yun)行時間和電(dian)壓比較穩定。
2)交流電機
交流(liu)電機(ji)(ji)按照電源(yuan)類(lei)型分(fen)為單(dan)(dan)相(xiang)(xiang)電機(ji)(ji)與三(san)相(xiang)(xiang)電機(ji)(ji)。單(dan)(dan)相(xiang)(xiang)電機(ji)(ji)采用(yong)單(dan)(dan)相(xiang)(xiang)交流(liu)電源(yuan)供(gong)電,定(ding)子(zi)(zi)僅含一個(ge)繞組(zu),需借助啟動(dong)線(xian)圈或(huo)運(yun)行電容器等以(yi)產生(sheng)旋(xuan)轉磁場。特點(dian)是結構簡單(dan)(dan)、維修方便(bian),多(duo)應(ying)用(yong)于小型家用(yong)電器等生(sheng)活場景。三(san)相(xiang)(xiang)電機(ji)(ji)采用(yong)三(san)相(xiang)(xiang)交流(liu)電源(yuan)供(gong)電,定(ding)子(zi)(zi)繞組(zu)分(fen)為三(san)組(zu),通入互(hu)差120°的交流(liu)電就可產生(sheng)旋(xuan)轉磁場。三(san)相(xiang)(xiang)電機(ji)(ji)效率高、功率大、可靠性和(he)精度高,多(duo)用(yong)于水泵、機(ji)(ji)床(chuang)等工業領域。
交流電機按照轉子轉速與定子旋轉磁場的轉速是否相同,交流電機分為同步電機與異步電機。同步電機的轉速恒定,而異步電機的轉速可以隨著負載的變化而調節。常見的電力拖動機械大多由異步電機驅動,如空氣壓縮機、鼓風機、大型起重設備等。而同步電機主要適用于要求轉速恒定的大功率生產機械,如連續式軋鋼機、球磨機等,由于其造價昂貴、維修困難而應用較少。