一、電抗器容量單位是什么
電抗器的容量通(tong)常以單(dan)(dan)位均勻(yun)(yun)量(VAr/km)為(wei)單(dan)(dan)位進行(xing)計量。單(dan)(dan)位均勻(yun)(yun)量是指在單(dan)(dan)位電壓(ya)和(he)頻率下,電抗器每(mei)公(gong)里長度上所能產生的無功電能。
在電(dian)力(li)系統中,通常使用的(de)都是(shi)大容量的(de)電(dian)抗器,其容量可達數百(bai)萬(wan)VAr,計量單位常常變(bian)化,比如:MVAR、GVAR等(deng),但它們的(de)基本單位都是(shi)VAr/km。
二、電抗器容量的表達方式
電抗器容量(liang)的常見表達(da)方式有(you)以下(xia)兩種:
1、以(yi)電(dian)抗器在額定電(dian)壓下(xia)消耗(hao)的無功功率表示(shi),這個值通(tong)常采用千伏安(an)(kVA)作為(wei)單位。
2、以(yi)電感值和頻率表(biao)示,這個值通常采用亨(heng)利(li)(H)作為(wei)單位(wei)。
三、電抗器的容量怎么計算
電(dian)(dian)抗(kang)器容量等于電(dian)(dian)容器容量乘以(yi)電(dian)(dian)抗(kang)率。例(li)如電(dian)(dian)抗(kang)器額定(ding)電(dian)(dian)壓(ya)是(shi)10kv,額定(ding)電(dian)(dian)流是(shi)800A,電(dian)(dian)抗(kang)率是(shi)4%,先算出:
額定端(duan)電壓:10除以根號3再乘以4%再乘1000,得(de)出額定端(duan)電壓231V。
電(dian)抗器容(rong)量:額定(ding)端電(dian)壓(ya)231V再乘以電(dian)流800A,既電(dian)抗器容(rong)量為184.8kvar。
電(dian)抗器的(de)額定(ding)電(dian)流(liu)I乘以(yi)(yi)其本(ben)省的(de)電(dian)壓降U再乘以(yi)(yi)相(xiang)數3或(huo)者(zhe)1等于容量(liang)Q,單位(wei)為乏(fa)(VAR),如果(guo)除以(yi)(yi)1000之后即(ji)為KVAR千乏(fa)。
四、電抗器容量偏小會有什么后果
電抗(kang)器(qi)(qi)容(rong)(rong)量(liang)偏小產生的(de)原因通常是由(you)于設(she)計問題或安(an)裝過程中的(de)錯誤。電抗(kang)器(qi)(qi)的(de)容(rong)(rong)量(liang)應(ying)根據設(she)備的(de)實際需(xu)求(qiu)而定(ding),如果未能(neng)(neng)準(zhun)確(que)計算電氣(qi)系統的(de)需(xu)求(qiu),則可能(neng)(neng)導致容(rong)(rong)量(liang)不(bu)足。此外,如果電抗(kang)器(qi)(qi)的(de)安(an)裝位置不(bu)當或布(bu)線(xian)不(bu)正確(que),也(ye)會(hui)導致容(rong)(rong)量(liang)偏小。當電抗(kang)器(qi)(qi)容(rong)(rong)量(liang)偏小時(shi)會(hui)產生以(yi)下(xia)兩種后(hou)果:
1、電流過大
電(dian)(dian)(dian)抗(kang)器是(shi)電(dian)(dian)(dian)氣系統中的一種重要電(dian)(dian)(dian)器元件,主要起(qi)到穩(wen)定(ding)電(dian)(dian)(dian)壓(ya)的作(zuo)用。在電(dian)(dian)(dian)動機(ji)等各類負載(zai)操(cao)作(zuo)時,電(dian)(dian)(dian)壓(ya)值會(hui)產生(sheng)波(bo)動和幅值降(jiang)低(di),為了保證(zheng)電(dian)(dian)(dian)壓(ya)穩(wen)定(ding),需要增(zeng)加電(dian)(dian)(dian)抗(kang)器來(lai)補償。如(ru)果電(dian)(dian)(dian)抗(kang)器的容量偏小,則無(wu)法承擔正常(chang)的補償作(zuo)用,電(dian)(dian)(dian)流過載(zai)是(shi)非(fei)常(chang)常(chang)見的問題。如(ru)果長期運(yun)行在這種狀態(tai)下,則不僅(jin)會(hui)造成(cheng)(cheng)設(she)備的損壞,還會(hui)對設(she)備和電(dian)(dian)(dian)氣系統造成(cheng)(cheng)更(geng)大的負擔。
2、電壓波動
除了電流過載的問題,容量偏小的電抗器還會導(dao)致(zhi)(zhi)(zhi)電(dian)(dian)(dian)壓(ya)波(bo)(bo)(bo)動(dong)。電(dian)(dian)(dian)氣系統中的電(dian)(dian)(dian)壓(ya)波(bo)(bo)(bo)動(dong)將(jiang)對設備產(chan)生(sheng)有(you)害影(ying)響,使設備無(wu)(wu)法正(zheng)常工作。在電(dian)(dian)(dian)源(yuan)削弱或運行負載時,電(dian)(dian)(dian)抗器(qi)的容量不(bu)足,導(dao)致(zhi)(zhi)(zhi)電(dian)(dian)(dian)流無(wu)(wu)法平(ping)滑(hua)流動(dong),從而產(chan)生(sheng)電(dian)(dian)(dian)壓(ya)波(bo)(bo)(bo)動(dong)。這會導(dao)致(zhi)(zhi)(zhi)各種故障,如設備損壞、電(dian)(dian)(dian)子(zi)產(chan)品(pin)及微(wei)處理(li)器(qi)故障等。