輪轂電機技術(shu)是什(shen)么 輪轂電機的優缺點(dian)分析(xi)
輪毅電機技術是什么
輪轂電機技術又稱車輪內裝電機技術,它的最大特點就是將動力、傳動和制動裝置都整合到輪轂內,因此將電動車輛的機械部分大大簡化。輪轂電機技術并非新生事物,早在1900年(nian),保時捷就首先(xian)制造出了前輪裝備輪轂電機的(de)電動(dong)汽車,在20世(shi)紀70年代,這一技術在(zai)礦山運輸車等領域得(de)到應用。而對(dui)于(yu)乘(cheng)用車所(suo)用的輪轂電機,日系廠商(shang)對(dui)于(yu)此(ci)項(xiang)(xiang)技術研發(fa)開展較早,目前(qian)處于(yu)領先地位,包括(kuo)通用、豐(feng)田在(zai)內的國際汽(qi)車巨頭也都(dou)對(dui)該技術有(you)所(suo)涉足。目前(qian)國內也有(you)自主(zhu)品牌汽(qi)車廠商(shang)開始(shi)研發(fa)此(ci)項(xiang)(xiang)技術,在(zai)2011年上(shang)海車展展出(chu)的瑞麒X1增程電動車就采(cai)用了輪轂電機技術。
輪轂電機驅動系統根據電機的轉子型式主要分成兩種結構型式:內轉子式和外轉子式。其中外轉子式采用低速外傳子電機,電機的最高轉速在1000-1500r/min,無減速(su)裝(zhuang)置,車輪的轉速(su)與電機相同;而(er)內(nei)轉子式則采用高速(su)內(nei)轉子電機,配備固定傳動比的減速(su)器,為獲(huo)得較(jiao)高的功率密度,電機的轉速(su)可高達10000r/min。隨著更為緊湊的(de)行星齒(chi)輪(lun)減速器的(de)出(chu)現,內轉(zhuan)子(zi)式輪(lun)轂電機在功率密度方(fang)面(mian)比低速外轉(zhuan)子(zi)式更具(ju)競(jing)爭力。
輪轂電機的優缺點
優點1:省略大量傳動部件,讓車輛結構更簡單
對于傳(chuan)統車輛(liang)來說(shuo),離合器(qi)(qi)、變(bian)速器(qi)(qi)、傳(chuan)動軸、差速器(qi)(qi)乃至(zhi)分動器(qi)(qi)都是必不(bu)(bu)可(ke)少(shao)的(de)(de),而這(zhe)(zhe)些部件不(bu)(bu)但重量不(bu)(bu)輕、讓車輛(liang)的(de)(de)結構更為復(fu)雜,同(tong)時也存在需要定期維護(hu)和故(gu)障率(lv)的(de)(de)問題。但是輪轂電(dian)機就很好地解決了這(zhe)(zhe)個(ge)問題。除開(kai)結構更為簡單之外,采(cai)用輪轂電(dian)機驅動的(de)(de)車輛(liang)可(ke)以(yi)獲得更好的(de)(de)空(kong)間利用率(lv),同(tong)時傳(chuan)動效(xiao)率(lv)也要高(gao)出不(bu)(bu)少(shao)。
優點2:可實現多種復雜的驅動方式
由(you)于輪(lun)轂(gu)(gu)電(dian)(dian)機(ji)具備單個(ge)車輪(lun)獨立驅(qu)動(dong)的(de)(de)特(te)(te)性,因此無(wu)論是前(qian)驅(qu)、后驅(qu)還是四(si)驅(qu)形式,它都可(ke)(ke)以(yi)(yi)比較輕松地(di)(di)實現(xian)(xian),全(quan)時四(si)驅(qu)在(zai)輪(lun)轂(gu)(gu)電(dian)(dian)機(ji)驅(qu)動(dong)的(de)(de)車輛(liang)上實現(xian)(xian)起來非(fei)常容(rong)易(yi)。同(tong)時輪(lun)轂(gu)(gu)電(dian)(dian)機(ji)可(ke)(ke)以(yi)(yi)通過左右車輪(lun)的(de)(de)不同(tong)轉速甚至(zhi)反轉實現(xian)(xian)類(lei)似履帶式車輛(liang)的(de)(de)差動(dong)轉向(xiang),大大減小車輛(liang)的(de)(de)轉彎半徑,在(zai)特(te)(te)殊情況下幾(ji)乎可(ke)(ke)以(yi)(yi)實現(xian)(xian)原地(di)(di)轉向(xiang)(不過此時對車輛(liang)轉向(xiang)機(ji)構和輪(lun)胎的(de)(de)磨(mo)損較大),對于特(te)(te)種(zhong)車輛(liang)很有價值。
優點3:便于采用多種新能源車技術
新(xin)能源車(che)(che)型(xing)不少都(dou)采用電(dian)(dian)(dian)驅(qu)動(dong),因(yin)此輪(lun)轂(gu)(gu)電(dian)(dian)(dian)機(ji)(ji)驅(qu)動(dong)也(ye)就(jiu)派上了大用場。無論是(shi)(shi)純電(dian)(dian)(dian)動(dong)還是(shi)(shi)燃料電(dian)(dian)(dian)池電(dian)(dian)(dian)動(dong)車(che)(che),抑或是(shi)(shi)增(zeng)程電(dian)(dian)(dian)動(dong)車(che)(che),都(dou)可(ke)以(yi)(yi)用輪(lun)轂(gu)(gu)電(dian)(dian)(dian)機(ji)(ji)作為(wei)(wei)主要(yao)驅(qu)動(dong)力(li);即便是(shi)(shi)對于混合(he)動(dong)力(li)車(che)(che)型(xing),也(ye)可(ke)以(yi)(yi)采用輪(lun)轂(gu)(gu)電(dian)(dian)(dian)機(ji)(ji)作為(wei)(wei)起步或者(zhe)急(ji)加(jia)速時的助力(li),可(ke)謂(wei)是(shi)(shi)一機(ji)(ji)多用。同時,新(xin)能源車(che)(che)的很多技術,比(bi)如(ru)制(zhi)動(dong)能量(liang)回收(即再生制(zhi)動(dong))也(ye)可(ke)以(yi)(yi)很輕松地在(zai)輪(lun)轂(gu)(gu)電(dian)(dian)(dian)機(ji)(ji)驅(qu)動(dong)車(che)(che)型(xing)上得(de)以(yi)(yi)實現。
缺點1:增大簧下質量和輪轂的轉動慣量,對車輛的操控有所影響
對(dui)(dui)(dui)于普通民用(yong)車(che)輛(liang)來說,常常用(yong)一(yi)些相對(dui)(dui)(dui)輕質的(de)材料比如(ru)鋁合金來制作(zuo)懸掛(gua)的(de)部(bu)件,以(yi)減輕簧下質量(liang)(liang),提升懸掛(gua)的(de)響(xiang)應(ying)速(su)度。可是(shi)輪轂電機恰好較大(da)幅度地增大(da)了(le)簧下質量(liang)(liang),同時也增加了(le)輪轂的(de)轉(zhuan)動(dong)慣量(liang)(liang),這對(dui)(dui)(dui)于車(che)輛(liang)的(de)操控(kong)性(xing)能是(shi)不(bu)利的(de)。不(bu)過考慮到電動(dong)車(che)型大(da)多限于代步而(er)非追求動(dong)力(li)性(xing)能,這一(yi)點(dian)尚(shang)不(bu)是(shi)最大(da)缺(que)陷。
缺點2:電制動性能有限,維持制動系統運行需要消耗不少電能
現在的(de)傳(chuan)統動(dong)(dong)(dong)(dong)(dong)(dong)(dong)力商用車(che)(che)已經有不(bu)少裝備(bei)了利用渦流制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)原理(也即(ji)電(dian)阻(zu)制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong))的(de)輔助(zhu)減(jian)速設備(bei),比如(ru)很(hen)多卡(ka)車(che)(che)所用的(de)電(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)緩(huan)速器。而由于(yu)能(neng)源的(de)關系,電(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)車(che)(che)采用電(dian)制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)也是首選,不(bu)過對(dui)于(yu)輪轂電(dian)機(ji)(ji)(ji)驅(qu)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)的(de)車(che)(che)輛,由于(yu)輪轂電(dian)機(ji)(ji)(ji)系統的(de)電(dian)制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)容量(liang)(liang)較(jiao)小,不(bu)能(neng)滿足整車(che)(che)制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)性能(neng)的(de)要求,都需(xu)要附加機(ji)(ji)(ji)械(xie)制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)系統,但(dan)是對(dui)于(yu)普通電(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)乘用車(che)(che),沒有了傳(chuan)統內燃(ran)機(ji)(ji)(ji)帶動(dong)(dong)(dong)(dong)(dong)(dong)(dong)的(de)真(zhen)空泵,就需(xu)要電(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)真(zhen)空泵來提(ti)供(gong)剎車(che)(che)助(zhu)力,但(dan)也就意味(wei)了有著(zhu)更大的(de)能(neng)量(liang)(liang)消耗(hao),即(ji)便是再生制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)能(neng)回收一些(xie)能(neng)量(liang)(liang),如(ru)果要確保制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)系統的(de)效(xiao)能(neng),制(zhi)(zhi)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)系統消耗(hao)的(de)能(neng)量(liang)(liang)也是影響(xiang)電(dian)動(dong)(dong)(dong)(dong)(dong)(dong)(dong)車(che)(che)續(xu)航(hang)里程的(de)重要因(yin)素之一。
此外,輪(lun)轂(gu)電(dian)機工作的環境惡(e)劣,面臨水、灰塵等多方面影響,在密封方面也(ye)有較(jiao)高要(yao)求(qiu),同時在設計上也(ye)需要(yao)為輪(lun)轂(gu)電(dian)機單獨考慮散(san)熱問題(ti)。
結語:
與電動機集中動力驅動相比,輪轂電機技術具備很大的優勢,它布局更為靈活,不需要復雜的機械傳動系統,同時也有自己的顯著不足,比如密封和起步電流/扭(niu)矩間的平(ping)衡關系,以及轉向(xiang)時(shi)驅(qu)動輪(lun)(lun)的差速問題等等,如果能在工程上解(jie)決這些難題,輪(lun)(lun)轂電機驅(qu)動技術將(jiang)在未(wei)來的新能源車中擁(yong)有廣闊的前景。