一、電抗器容量單位是什么
電抗器的容量(liang)通常(chang)以單(dan)位(wei)(wei)均(jun)勻(yun)量(liang)(VAr/km)為單(dan)位(wei)(wei)進行計量(liang)。單(dan)位(wei)(wei)均(jun)勻(yun)量(liang)是指在單(dan)位(wei)(wei)電壓和頻率(lv)下,電抗器(qi)每(mei)公里長度上所(suo)能產生的無功(gong)電能。
在電(dian)力系統中(zhong),通常使用的(de)都是大容量的(de)電(dian)抗器,其容量可達數百(bai)萬(wan)VAr,計量單(dan)位常常變化,比如:MVAR、GVAR等,但(dan)它們的(de)基(ji)本單(dan)位都是VAr/km。
二、電抗器容量的表達方式
電抗(kang)器容量的常見表達方式有(you)以下兩種:
1、以電(dian)抗(kang)器在(zai)額定電(dian)壓下消耗的無功功率表示,這(zhe)個值(zhi)通(tong)常采用千伏(fu)安(an)(kVA)作為單位。
2、以電(dian)感(gan)值和(he)頻率表示(shi),這個值通(tong)常采(cai)用亨利(H)作為單位。
三、電抗器的容量怎么計算
電(dian)抗(kang)器容(rong)(rong)量(liang)等于(yu)電(dian)容(rong)(rong)器容(rong)(rong)量(liang)乘以電(dian)抗(kang)率。例如電(dian)抗(kang)器額(e)定電(dian)壓是(shi)10kv,額(e)定電(dian)流是(shi)800A,電(dian)抗(kang)率是(shi)4%,先算(suan)出:
額(e)定(ding)(ding)端電壓(ya):10除以(yi)根號3再乘(cheng)以(yi)4%再乘(cheng)1000,得出(chu)額(e)定(ding)(ding)端電壓(ya)231V。
電(dian)抗(kang)器容(rong)量:額定端電(dian)壓(ya)231V再乘以電(dian)流800A,既電(dian)抗(kang)器容(rong)量為(wei)184.8kvar。
電(dian)抗器的(de)(de)額定電(dian)流(liu)I乘(cheng)以(yi)其本省的(de)(de)電(dian)壓降(jiang)U再(zai)乘(cheng)以(yi)相數3或者1等于容量Q,單位為乏(VAR),如果除以(yi)1000之(zhi)后即為KVAR千乏。
四、電抗器容量偏小會有什么后果
電(dian)(dian)抗(kang)器(qi)(qi)容(rong)量偏小產生的原因通常是由于設(she)計問題或安裝(zhuang)過(guo)程(cheng)中的錯(cuo)誤(wu)。電(dian)(dian)抗(kang)器(qi)(qi)的容(rong)量應(ying)根(gen)據設(she)備的實際需求(qiu)而定(ding),如果未能(neng)準(zhun)確計算電(dian)(dian)氣系統的需求(qiu),則可(ke)能(neng)導致容(rong)量不足。此外,如果電(dian)(dian)抗(kang)器(qi)(qi)的安裝(zhuang)位置不當或布線不正(zheng)確,也會(hui)(hui)導致容(rong)量偏小。當電(dian)(dian)抗(kang)器(qi)(qi)容(rong)量偏小時會(hui)(hui)產生以下兩種(zhong)后果:
1、電流過大
電(dian)(dian)(dian)(dian)抗(kang)(kang)器是電(dian)(dian)(dian)(dian)氣(qi)系統中的(de)一種重(zhong)要電(dian)(dian)(dian)(dian)器元(yuan)件,主要起(qi)到穩定電(dian)(dian)(dian)(dian)壓(ya)(ya)的(de)作(zuo)(zuo)用。在電(dian)(dian)(dian)(dian)動機(ji)等各類負載(zai)操作(zuo)(zuo)時,電(dian)(dian)(dian)(dian)壓(ya)(ya)值(zhi)會(hui)產生(sheng)波(bo)動和幅值(zhi)降低(di),為了(le)保證(zheng)電(dian)(dian)(dian)(dian)壓(ya)(ya)穩定,需要增(zeng)加(jia)電(dian)(dian)(dian)(dian)抗(kang)(kang)器來補(bu)(bu)償(chang)。如果電(dian)(dian)(dian)(dian)抗(kang)(kang)器的(de)容量(liang)偏(pian)小,則無(wu)法承擔正(zheng)常的(de)補(bu)(bu)償(chang)作(zuo)(zuo)用,電(dian)(dian)(dian)(dian)流過載(zai)是非常常見的(de)問題。如果長期運行在這種狀(zhuang)態下,則不僅會(hui)造成設備的(de)損壞,還會(hui)對設備和電(dian)(dian)(dian)(dian)氣(qi)系統造成更大的(de)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)電(dian)(dian)壓波動(dong)。電(dian)(dian)氣系統中(zhong)的(de)電(dian)(dian)壓波動(dong)將對設(she)備產生(sheng)(sheng)有害影響,使設(she)備無(wu)法正常(chang)工作。在電(dian)(dian)源削弱或運(yun)行負(fu)載時,電(dian)(dian)抗(kang)器(qi)的(de)容量不足,導(dao)致(zhi)電(dian)(dian)流無(wu)法平滑流動(dong),從而產生(sheng)(sheng)電(dian)(dian)壓波動(dong)。這(zhe)會導(dao)致(zhi)各種(zhong)故障,如設(she)備損壞、電(dian)(dian)子(zi)產品(pin)及微處理(li)器(qi)故障等。