2021-06-17 17:27:23
趙雨
707
提及“無(wu)功(gong)(gong)補(bu)償”，首先(xian)我們要(yao)了(le)解(jie)無(wu)功(gong)(gong)功(gong)(gong)率的概念(nian)，什么是無(wu)功(gong)(gong)功(gong)(gong)率？
人們對有功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率相對容(rong)(rong)易理解，因(yin)為它(ta)能(neng)做(zuo)(zuo)功(gong)(gong)(gong)(gong)、產(chan)生(sheng)熱量、帶(dai)動電(dian)(dian)(dian)(dian)(dian)機旋轉(zhuan)等。例(li)(li)如，當(dang)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)通(tong)過純電(dian)(dian)(dian)(dian)(dian)阻(zu)時，電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)能(neng)使電(dian)(dian)(dian)(dian)(dian)阻(zu)發熱，是(shi)(shi)實實在(zai)(zai)在(zai)(zai)能(neng)感(gan)受得(de)到的(de)功(gong)(gong)(gong)(gong)率。但“無(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率”一般則難于理解，它(ta)僅存在(zai)(zai)于交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)中，直流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)不(bu)(bu)(bu)存在(zai)(zai)無(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率的(de)問題。例(li)(li)如，當(dang)交(jiao)(jiao)流(liu)(liu)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)通(tong)過純電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)或純電(dian)(dian)(dian)(dian)(dian)感(gan)負載時并不(bu)(bu)(bu)做(zuo)(zuo)功(gong)(gong)(gong)(gong)，也(ye)就是(shi)(shi)說純電(dian)(dian)(dian)(dian)(dian)容(rong)(rong)或者(zhe)純電(dian)(dian)(dian)(dian)(dian)感(gan)負載不(bu)(bu)(bu)消耗有功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率，但在(zai)(zai)它(ta)們中流(liu)(liu)過的(de)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)以及對應(ying)電(dian)(dian)(dian)(dian)(dian)壓(ya)就形成了交(jiao)(jiao)流(liu)(liu)功(gong)(gong)(gong)(gong)率，這種交(jiao)(jiao)流(liu)(liu)功(gong)(gong)(gong)(gong)率即稱為無(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率。理論(lun)上講(jiang)，無(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率是(shi)(shi)不(bu)(bu)(bu)做(zuo)(zuo)工的(de)，當(dang)然它(ta)不(bu)(bu)(bu)應(ying)該產(chan)生(sheng)光和熱，更不(bu)(bu)(bu)能(neng)帶(dai)動電(dian)(dian)(dian)(dian)(dian)機的(de)旋轉(zhuan)。
往往我們(men)遇到的(de)(de)負(fu)載很(hen)少有(you)純感性或純容(rong)性的(de)(de)，一(yi)般都(dou)是(shi)混合性負(fu)載，這樣(yang)電(dian)流在(zai)通(tong)過它們(men)的(de)(de)時(shi)候，有(you)部分功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)能(neng)(neng)(neng)做(zuo)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)，有(you)部分功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)不(bu)(bu)能(neng)(neng)(neng)做(zuo)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)，不(bu)(bu)能(neng)(neng)(neng)做(zuo)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)的(de)(de)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)就是(shi)無(wu)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)，為了(le)(le)直(zhi)觀的(de)(de)體現(xian)無(wu)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)和有(you)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)的(de)(de)關系，人們(men)采用(yong)(yong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)因數的(de)(de)概念(nian)來表述電(dian)能(neng)(neng)(neng)的(de)(de)利(li)用(yong)(yong)率(lv)(lv)(lv)(lv)。功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)因數越接近1，說(shuo)明(ming)有(you)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)的(de)(de)占(zhan)比(bi)高(gao)，電(dian)能(neng)(neng)(neng)的(de)(de)利(li)用(yong)(yong)率(lv)(lv)(lv)(lv)高(gao)；反之，功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)因數越接近0，說(shuo)明(ming)有(you)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)率(lv)(lv)(lv)(lv)的(de)(de)占(zhan)比(bi)低(di)，電(dian)能(neng)(neng)(neng)的(de)(de)利(li)用(yong)(yong)率(lv)(lv)(lv)(lv)則低(di)。為了(le)(le)提高(gao)電(dian)能(neng)(neng)(neng)的(de)(de)利(li)用(yong)(yong)率(lv)(lv)(lv)(lv)，就提出了(le)(le)“無(wu)功(gong)(gong)(gong)(gong)(gong)(gong)(gong)補償(chang)”的(de)(de)概念(nian)。
了(le)(le)解了(le)(le)無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)率、有(you)功(gong)(gong)(gong)功(gong)(gong)(gong)率、功(gong)(gong)(gong)率因數的概念，也(ye)知(zhi)道了(le)(le)無(wu)功(gong)(gong)(gong)補(bu)償(chang)的根本目的就(jiu)是(shi)提高(gao)電能利用率。接下(xia)來我們具體分(fen)析下(xia)：為什(shen)么(me)要進行無(wu)功(gong)(gong)(gong)補(bu)償(chang)、無(wu)功(gong)(gong)(gong)補(bu)償(chang)的原(yuan)理是(shi)什(shen)么(me)、補(bu)償(chang)形式(shi)有(you)哪(na)些以及補(bu)償(chang)經(jing)濟性(xing)的分(fen)析等。
一、為什么要進(jin)行無功補償
無(wu)(wu)(wu)功(gong)功(gong)率(lv)不是無(wu)(wu)(wu)用功(gong)率(lv)，在交流供電(dian)(dian)系(xi)統(tong)(tong)(tong)中，電(dian)(dian)感(gan)和電(dian)(dian)容都是必不可少(shao)的(de)(de)負(fu)載，如(ru)電(dian)(dian)動機、變(bian)壓器等鐵磁(ci)(ci)性(xing)負(fu)載，如(ru)果沒有(you)感(gan)性(xing)無(wu)(wu)(wu)功(gong)的(de)(de)勵磁(ci)(ci)，設備無(wu)(wu)(wu)法正(zheng)常(chang)工作(zuo)，比如(ru)定距(ju)離(li)送電(dian)(dian)的(de)(de)線路(lu)本身，就是容性(xing)負(fu)載，只要是送電(dian)(dian)當(dang)中就會相當(dang)于電(dian)(dian)容器在工作(zuo)。那么也就是說在交流供電(dian)(dian)系(xi)統(tong)(tong)(tong)中，無(wu)(wu)(wu)功(gong)的(de)(de)存在對功(gong)率(lv)的(de)(de)傳輸和交換有(you)著巨(ju)大意義，不可缺少(shao)，或者說離(li)開無(wu)(wu)(wu)功(gong)功(gong)率(lv)的(de)(de)交換系(xi)統(tong)(tong)(tong)就不能正(zheng)常(chang)工作(zuo)。
那么，大量的(de)無(wu)功(gong)(gong)由(you)哪里(li)來(lai)？系(xi)統(tong)(tong)中眾多的(de)無(wu)功(gong)(gong)負(fu)載(zai)，尤其是(shi)(shi)感性(xing)無(wu)功(gong)(gong)負(fu)載(zai)，正常來(lai)講(jiang)，這(zhe)些(xie)負(fu)載(zai)所(suo)吸收(shou)的(de)無(wu)功(gong)(gong)功(gong)(gong)率是(shi)(shi)由(you)發(fa)電(dian)廠提供的(de)，也就(jiu)(jiu)(jiu)是(shi)(shi)說(shuo)發(fa)電(dian)機在工作時(shi)就(jiu)(jiu)(jiu)會(hui)向系(xi)統(tong)(tong)釋(shi)放有(you)功(gong)(gong)電(dian)能，同時(shi)對(dui)感性(xing)負(fu)載(zai)提供相(xiang)應的(de)無(wu)功(gong)(gong)電(dian)能。發(fa)電(dian)機運行時(shi)需(xu)要(yao)要(yao)保(bao)持適(shi)當的(de)無(wu)功(gong)(gong)輸出，如果沒有(you)無(wu)功(gong)(gong)輸出就(jiu)(jiu)(jiu)會(hui)對(dui)發(fa)電(dian)系(xi)統(tong)(tong)造成破壞性(xing)的(de)影響,也就(jiu)(jiu)(jiu)是(shi)(shi)說(shuo)保(bao)護系(xi)統(tong)(tong)的(de)無(wu)功(gong)(gong)平(ping)衡*關(guan)重要(yao)。
當系統中無功(gong)功(gong)率需求(qiu)增(zeng)加時，如(ru)果不(bu)在系統人為地安裝(zhuang)無功(gong)補償裝(zhuang)置，發(fa)電(dian)(dian)(dian)廠要通(tong)過調相的(de)(de)(de)(de)方(fang)式來加大(da)無功(gong)功(gong)率輸出，由于發(fa)電(dian)(dian)(dian)機(ji)的(de)(de)(de)(de)容(rong)量是有限的(de)(de)(de)(de)，那(nei)么就勢必要減少有功(gong)功(gong)率的(de)(de)(de)(de)輸出量，也就是降低(di)發(fa)電(dian)(dian)(dian)機(ji)的(de)(de)(de)(de)輸出能力，為滿足用電(dian)(dian)(dian)的(de)(de)(de)(de)要求(qiu)，發(fa)電(dian)(dian)(dian)機(ji)、供電(dian)(dian)(dian)線(xian)路和變壓(ya)器的(de)(de)(de)(de)容(rong)量需增(zeng)加，這樣不(bu)僅增(zeng)加供電(dian)(dian)(dian)投資、降低(di)設備利用率，也將增(zeng)加線(xian)路損耗。
為了降低發(fa)電(dian)廠的(de)(de)(de)(de)無(wu)功(gong)供(gong)(gong)給壓(ya)力，我們在供(gong)(gong)電(dian)系統中感性負載(zai)消(xiao)耗(hao)較(jiao)大的(de)(de)(de)(de)點(dian)投入(ru)(ru)相(xiang)應的(de)(de)(de)(de)電(dian)容器來為感性負載(zai)提(ti)(ti)供(gong)(gong)無(wu)功(gong)功(gong)率，這樣就減輕(qing)了發(fa)電(dian)廠的(de)(de)(de)(de)無(wu)功(gong)供(gong)(gong)給壓(ya)力。用(yong)戶應在提(ti)(ti)高用(yong)電(dian)自(zi)(zi)然功(gong)率因數的(de)(de)(de)(de)基礎上，設計和裝設無(wu)功(gong)補償裝置，并做到(dao)隨其負荷和電(dian)壓(ya)變動及時投入(ru)(ru)或切(qie)除，防(fang)止無(wu)功(gong)倒送(song)。同(tong)時將用(yong)戶的(de)(de)(de)(de)功(gong)率因數達到(dao)相(xiang)應的(de)(de)(de)(de)標(biao)準(zhun)，以避(bi)免供(gong)(gong)電(dian)部門(men)加收力率電(dian)費。因此，無(wu)論對(dui)供(gong)(gong)電(dian)部門(men)還是用(yong)電(dian)部門(men)，對(dui)無(wu)功(gong)功(gong)率進(jin)行(xing)自(zi)(zi)動補償以提(ti)(ti)高功(gong)率因數，防(fang)止無(wu)功(gong)倒送(song)，對(dui)節約電(dian)能、提(ti)(ti)高運行(xing)質量都具(ju)有(you)非常重要的(de)(de)(de)(de)意義。
二、無功補(bu)償的原理是(shi)什么
1、從吸(xi)收功率(lv)和釋放(fang)功率(lv)角(jiao)度分(fen)析
一(yi)般在(zai)系統(tong)中所(suo)說(shuo)的(de)無(wu)(wu)功(gong)(gong)(gong)(gong)負(fu)載大部分是感(gan)性無(wu)(wu)功(gong)(gong)(gong)(gong)負(fu)載，把具有(you)容性功(gong)(gong)(gong)(gong)率(lv)負(fu)荷(he)的(de)裝(zhuang)置與感(gan)性功(gong)(gong)(gong)(gong)率(lv)負(fu)荷(he)并聯接(jie)在(zai)同(tong)一(yi)電(dian)路，當感(gan)性無(wu)(wu)功(gong)(gong)(gong)(gong)負(fu)載吸收(shou)(shou)功(gong)(gong)(gong)(gong)率(lv)時，容性負(fu)載釋放功(gong)(gong)(gong)(gong)率(lv)，而感(gan)性負(fu)載釋放功(gong)(gong)(gong)(gong)率(lv)時，容性負(fu)荷(he)卻在(zai)吸收(shou)(shou)功(gong)(gong)(gong)(gong)率(lv)，功(gong)(gong)(gong)(gong)率(lv)在(zai)容性負(fu)載和(he)感(gan)性負(fu)載之間交換，這(zhe)樣容性負(fu)載所(suo)吸收(shou)(shou)的(de)無(wu)(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率(lv)可(ke)以(yi)從(cong)感(gan)性負(fu)荷(he)裝(zhuang)置輸出的(de)無(wu)(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率(lv)中得到補償，無(wu)(wu)功(gong)(gong)(gong)(gong)功(gong)(gong)(gong)(gong)率(lv)就(jiu)地(di)平衡掉，以(yi)降低(di)線路損(sun)失(shi)，提高帶(dai)載能(neng)力，降低(di)電(dian)壓損(sun)失(shi)及緩(huan)和(he)發電(dian)廠(chang)的(de)供電(dian)壓力，這(zhe)就(jiu)是無(wu)(wu)功(gong)(gong)(gong)(gong)補償的(de)基本原(yuan)理(li)。
2、從(cong)相位（感性(xing)/容(rong)性(xing)）角(jiao)度(du)分析
純電感負載中(zhong)電流(liu)IL滯后電壓(ya)(ya)90°，其功(gong)(gong)率(lv)(lv)(lv)稱為感性無功(gong)(gong)功(gong)(gong)率(lv)(lv)(lv)；而(er)純電容負載中(zhong)電流(liu)Ic則超前(qian)電壓(ya)(ya)90°，其功(gong)(gong)率(lv)(lv)(lv)稱為容性無功(gong)(gong)功(gong)(gong)率(lv)(lv)(lv)。
電(dian)(dian)容中的電(dian)(dian)流與電(dian)(dian)感中的電(dian)(dian)流相(xiang)位(wei)相(xiang)差180°,可以(yi)(yi)相(xiang)互(hu)抵消(xiao)(xiao)。電(dian)(dian)力系統中的負載(zai)大部(bu)分是感性負載(zai)，因(yin)此(ci)總電(dian)(dian)流I將滯后電(dian)(dian)壓(ya)一個角(jiao)度Φ1,如果將并聯(lian)(lian)電(dian)(dian)容器(qi)與負載(zai)并聯(lian)(lian)，這時I′＝I+IC,電(dian)(dian)容器(qi)的電(dian)(dian)流將抵消(xiao)(xiao)一部(bu)分電(dian)(dian)感電(dian)(dian)流，從而使總電(dian)(dian)流從I降低(di)到I′，相(xiang)位(wei)角(jiao)由Φ1減少為Φ2,可以(yi)(yi)提高功(gong)率因(yin)數，無(wu)功(gong)就地得到治理。
三、無功補償(chang)的形(xing)式有(you)哪些
廣(guang)義上(shang)講，無功補(bu)償的形式種類較多，比如(ru)：
按照補(bu)償(chang)并網點PCC點電壓(ya)等(deng)*不同，可分(fen)為高壓(ya)補(bu)償(chang)、中(zhong)壓(ya)補(bu)償(chang)、低(di)壓(ya)補(bu)償(chang)；
按照(zhao)補償點在輸配電(dian)(dian)系統中的位置不同，可分為設備側就(jiu)地補償、區域(yu)局部補償、變電(dian)(dian)所集中補償；
按(an)照(zhao)補(bu)(bu)償設備類(lei)型，可分(fen)為投(tou)(tou)切(qie)電(dian)容(rong)器補(bu)(bu)償（FC補(bu)(bu)償）、機(ji)械旋(xuan)轉類(lei)補(bu)(bu)償（如(ru)：同(tong)步調相機(ji)、同(tong)步發電(dian)機(ji)、同(tong)步電(dian)動機(ji)）、靜(jing)止(zhi)類(lei)無功補(bu)(bu)償（靜(jing)止(zhi)無功補(bu)(bu)償器：晶(jing)閘管投(tou)(tou)切(qie)電(dian)容(rong)TSC、晶(jing)閘管控制電(dian)抗器TCR、磁控電(dian)抗器MCR；靜(jing)止(zhi)同(tong)步補(bu)(bu)償器STATCOM；靜(jing)止(zhi)無功發生(sheng)器SVG）、復合(he)類(lei)無功補(bu)(bu)償（FC+TCR、FC+MCR、FC+STATCOM）等。
3.1按(an)照(zhao)補(bu)償(chang)位(wei)置區分的補(bu)償(chang)形(xing)式
接下(xia)來主要(yao)針對低壓0.4KV系(xi)統補(bu)償點位置不(bu)同(tong)，無功補(bu)償的形式做個簡單介紹。
1、設備側(ce)就地補償
設備(bei)側就地(di)(di)補償(chang)就是對單臺用(yong)電(dian)(dian)(dian)(dian)設備(bei)所(suo)需的(de)(de)無(wu)功就近(jin)補償(chang)的(de)(de)辦法，把(ba)電(dian)(dian)(dian)(dian)容器(qi)直接(jie)(jie)接(jie)(jie)到單臺用(yong)電(dian)(dian)(dian)(dian)設備(bei)的(de)(de)同(tong)(tong)一(yi)個電(dian)(dian)(dian)(dian)氣回路，用(yong)同(tong)(tong)一(yi)臺開(kai)關控制，同(tong)(tong)時投運或斷開(kai)。這(zhe)種(zhong)(zhong)補償(chang)方(fang)法的(de)(de)效果較好，電(dian)(dian)(dian)(dian)容器(qi)靠近(jin)用(yong)電(dian)(dian)(dian)(dian)設備(bei)，就地(di)(di)平衡(heng)無(wu)功電(dian)(dian)(dian)(dian)流，可避免無(wu)負荷時的(de)(de)過補償(chang)，使供電(dian)(dian)(dian)(dian)質(zhi)量得到保證。這(zhe)種(zhong)(zhong)補償(chang)方(fang)式常用(yong)于高低(di)壓電(dian)(dian)(dian)(dian)動機(ji)等用(yong)電(dian)(dian)(dian)(dian)設備(bei)。但(dan)這(zhe)種(zhong)(zhong)補償(chang)方(fang)式在用(yong)戶設備(bei)非連續運轉時，電(dian)(dian)(dian)(dian)容器(qi)利(li)用(yong)率低(di)，不能充分發揮其補償(chang)效益。
2、區域局部補(bu)償
區域局(ju)部補(bu)償是將電(dian)(dian)容器分組(zu)安裝(zhuang)在車間配電(dian)(dian)室或變電(dian)(dian)所各(ge)分路的出(chu)線上，它可以(yi)根(gen)據(ju)系統(tong)負荷的變化投入或切(qie)除電(dian)(dian)容器組(zu)，補(bu)償效果也(ye)比較(jiao)好(hao)，但造價相對(dui)較(jiao)高(gao)。
3、變電所集中補償(chang)
變(bian)電(dian)所(suo)集中補(bu)償是所(suo)有電(dian)容(rong)器(qi)組(zu)集中安(an)(an)裝(zhuang)在(zai)變(bian)電(dian)所(suo)的(de)(de)一次或二次側的(de)(de)母線上。這(zhe)種(zhong)補(bu)償方式安(an)(an)裝(zhuang)簡單，運行可靠(kao)，可以(yi)集中補(bu)償低(di)壓(ya)(ya)0.4KV系統的(de)(de)無(wu)功(gong)(gong)功(gong)(gong)率，對于變(bian)壓(ya)(ya)器(qi)原(yuan)邊（一般是10KV計量點）功(gong)(gong)率因數的(de)(de)提升有比(bi)較(jiao)直接的(de)(de)效(xiao)果，這(zhe)類補(bu)償方式是當前(qian)采用廣泛，性價比(bi)相(xiang)對比(bi)較(jiao)高的(de)(de)方案。
3.2按照(zhao)補償設(she)備類型區分(fen)的(de)補償形式
按(an)照補償(chang)設備(bei)類型細分的設備(bei)就(jiu)非常多了，一(yi)般都是按(an)照現場實際(ji)運行(xing)設備(bei)類型，各個(ge)(ge)補償(chang)設備(bei)運行(xing)都各有(you)利弊，在(zai)本(ben)文中(zhong)(zhong)我們主(zhu)要針對市場上(shang)0.4KV配電系(xi)統(tong)中(zhong)(zhong)應(ying)用廣泛的兩類產品——投切電容器補償(chang)（FC補償(chang)）和靜止無功發(fa)生(sheng)器（SVG補償(chang)），在(zai)此給大(da)家做個(ge)(ge)簡單的介紹。
1、投(tou)切電容器(qi)補(bu)償(chang)(chang)（FC補(bu)償(chang)(chang)）
投切(qie)電容器(qi)補償(chang)也就(jiu)是傳統(tong)的并聯電容器(qi)補償(chang)方式，他的原理是通過增(zeng)加容性(xing)無功(gong)補償(chang)負載的感性(xing)無功(gong)需求，提升負載電壓(ya)的穩定性(xing)，提高功(gong)率(lv)因(yin)數。
由于(yu)早期(qi)并(bing)聯電(dian)(dian)容器(qi)(qi)的(de)(de)(de)(de)投切(qie)是(shi)通過接觸器(qi)(qi)來實現，接觸器(qi)(qi)動作時(shi)間都是(shi)秒*，所以(yi)它的(de)(de)(de)(de)致(zhi)命缺(que)點(dian)是(shi)：合(he)閘涌流(liu)大，嚴重的(de)(de)(de)(de)情況下可以(yi)達到補償(chang)電(dian)(dian)容器(qi)(qi)額定(ding)電(dian)(dian)流(liu)的(de)(de)(de)(de)50-100倍，會產生較大的(de)(de)(de)(de)弧光，造成電(dian)(dian)容器(qi)(qi)和(he)接觸器(qi)(qi)的(de)(de)(de)(de)損(sun)壞。根據現場(chang)負載實際運行情況，市場(chang)上(shang)逐漸出現同(tong)步開關、復(fu)合(he)開關、晶閘管開關等(deng)替代接觸器(qi)(qi)的(de)(de)(de)(de)方案(an)，在電(dian)(dian)壓過零點(dian)合(he)閘、電(dian)(dian)流(liu)過零點(dian)切(qie)斷(duan)方面有了(le)很(hen)大的(de)(de)(de)(de)提升(sheng)，大大降低了(le)投切(qie)涌流(liu)導致(zhi)的(de)(de)(de)(de)設備損(sun)壞。
為了(le)投切(qie)控(kong)制(zhi)智能化、采集(ji)系統數據多(duo)元化、保護功能多(duo)樣化、安(an)裝維(wei)護簡(jian)單(dan)化，近些年又衍生出了(le)另一(yi)類投切(qie)電(dian)(dian)(dian)容(rong)(rong)器補償——智能電(dian)(dian)(dian)容(rong)(rong)，相比(bi)于傳統的(de)電(dian)(dian)(dian)容(rong)(rong)補償，它(ta)具有多(duo)項(xiang)技術功能是傳統電(dian)(dian)(dian)容(rong)(rong)器無法實現的(de)。另外(wai)，隨著負載設備電(dian)(dian)(dian)力電(dian)(dian)(dian)子化，配電(dian)(dian)(dian)系統諧波(bo)影響不(bu)容(rong)(rong)忽視，尤其對電(dian)(dian)(dian)容(rong)(rong)的(de)影響，所以針對諧波(bo)的(de)影響，FC補償也(ye)做了(le)很多(duo)相關改(gai)進，比(bi)如(ru)提出串抗(kang)(kang)率(lv)的(de)概念，什么情況(kuang)下用6%、7%的(de)串抗(kang)(kang)率(lv)？什么情況(kuang)下用13%、14%的(de)串抗(kang)(kang)率(lv)？這(zhe)部(bu)分內(nei)容(rong)(rong)后期做專題進一(yi)步講解。
2、靜止(zhi)無功發生器（SVG補償）
靜(jing)止無功發生(sheng)器(qi)是一種(zhong)用于(yu)補償(chang)無功的(de)新型電(dian)力(li)電(dian)子裝(zhuang)置，它能對大小變化的(de)無功以及負序進行(xing)快速和(he)連續的(de)補償(chang)，其應用可(ke)克(ke)服FC補償(chang)器(qi)等傳(chuan)統的(de)無功補償(chang)器(qi)響應速度慢、補償(chang)效果不能合(he)理控(kong)制、容易與(yu)電(dian)網(wang)發生(sheng)并聯諧振和(he)投切震蕩等缺點。
相(xiang)比于FC補(bu)償(chang)大的(de)三點*勢在于：
①線(xian)性補償(chang)無功(gong)功(gong)率，補償(chang)階梯小于(yu)1KVar；
②無木及性補償(chang)，既可以輸出容性無功(gong)，也可以輸出感性無功(gong)；
③響(xiang)應時間(jian)快(kuai)，全響(xiang)應時間(jian)小于5ms。
四(si)、無功補償的(de)經濟(ji)效(xiao)益
1、補償無功(gong)功(gong)率(lv)，提高功(gong)率(lv)因數
根據《功(gong)率(lv)因(yin)數(shu)調(diao)整電費辦(ban)法》的通知內(nei)容，不難發現，功(gong)率(lv)因(yin)數(shu)以0.9為標(biao)準值的力(li)(li)率(lv)調(diao)整規定，提高功(gong)率(lv)因(yin)數(shu)可以減少總電費的繳納，甚*功(gong)率(lv)因(yin)數(shu)高于0.9的配電用(yong)戶，還能獲得電力(li)(li)公司力(li)(li)率(lv)調(diao)整的獎勵(li)費用(yong)。
通過(guo)合理的(de)補償，使計量點的(de)功(gong)率(lv)因數(shu)達到國家標準的(de)要求，可(ke)以去除力(li)率(lv)電費，從而使電力(li)用戶電費支出大幅度(du)降低(di)。
動態無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)率補償(chang)(chang)裝置的(de)(de)(de)有功(gong)(gong)(gong)節能(neng)只是降低了補償(chang)(chang)點*發電(dian)機之間(jian)的(de)(de)(de)供(gong)配電(dian)的(de)(de)(de)損(sun)(sun)耗。所以高(gao)壓網(wang)側(ce)的(de)(de)(de)無(wu)功(gong)(gong)(gong)補償(chang)(chang)不能(neng)減少(shao)低壓閥側(ce)的(de)(de)(de)損(sun)(sun)耗，亦(yi)不能(neng)使低壓供(gong)電(dian)變壓器的(de)(de)(de)利(li)用率提高(gao)，根據(ju)合(he)適的(de)(de)(de)補償(chang)(chang)理論，就地動態無(wu)功(gong)(gong)(gong)功(gong)(gong)(gong)率補償(chang)(chang)節能(neng)效果顯著。
另外，市(shi)場上(shang)(shang)很多補償(chang)(chang)設備宣傳“節能(neng)”“省(sheng)電”等等概念，也基本上(shang)(shang)都是從無功補償(chang)(chang)入(ru)手，提高(gao)功率(lv)因數(shu)，減(jian)少力率(lv)罰款，或者由力率(lv)罰款轉化為(wei)力率(lv)獎勵的(de)方式(shi)，實(shi)現為(wei)配電用戶省(sheng)錢的(de)目的(de)。所以(yi)關于無功補償(chang)(chang)，在自(zi)然界功率(lv)傳遞的(de)角度認識的(de)話(hua)，嚴格講(jiang)并不屬于“節能(neng)”“省(sheng)電”范疇，但(dan)是實(shi)實(shi)在在可(ke)以(yi)給(gei)配電用戶省(sheng)錢。
2、降低輸電線路及變壓器的損耗
合(he)理的(de)(de)(de)補償可(ke)以(yi)合(he)理的(de)(de)(de)降(jiang)(jiang)低(di)(di)系(xi)統電流，以(yi)系(xi)統自然(ran)功(gong)(gong)率0.7為例，如通過補償裝(zhuang)置將系(xi)統功(gong)(gong)率因(yin)(yin)數提(ti)高到接近1的(de)(de)(de)水平(ping)，系(xi)統電流將下(xia)降(jiang)(jiang)30%左(zuo)右，即(ji)線路和(he)變壓(ya)(ya)器(qi)(qi)的(de)(de)(de)損(sun)耗(hao)(hao)可(ke)降(jiang)(jiang)為P=I2R＝(1-30%)2R=0.49R，即(ji)線路和(he)變壓(ya)(ya)器(qi)(qi)損(sun)耗(hao)(hao)可(ke)降(jiang)(jiang)低(di)(di)51%。用電企業(ye)的(de)(de)(de)自然(ran)功(gong)(gong)率因(yin)(yin)數一般(ban)在0.7左(zuo)右，功(gong)(gong)率因(yin)(yin)數從0.7提(ti)高到0.95以(yi)上線損(sun)降(jiang)(jiang)低(di)(di)率和(he)變壓(ya)(ya)器(qi)(qi)的(de)(de)(de)銅損(sun)降(jiang)(jiang)低(di)(di)率如下(xia)表：
降(jiang)(jiang)低線路及變(bian)壓(ya)器損耗，節(jie)約有(you)功電(dian)度，是(shi)重(zhong)要的節(jie)能措施(shi)。如在石油行(xing)業(ye)中，線路比較長，而且比較復(fu)雜，那么(me)可(ke)以通(tong)過(guo)增(zeng)加無功補償設備來(lai)降(jiang)(jiang)低運行(xing)電(dian)流，從而降(jiang)(jiang)低線路損耗，節(jie)約有(you)功電(dian)度，節(jie)能效果明顯。
3、增加電網的(de)傳輸能(neng)力(li)，提(ti)高設(she)備(bei)利用率
由于補償裝(zhuang)置可以合(he)理的降低(di)系(xi)(xi)統(tong)電流和視在功率，故可以合(he)理的降低(di)電網建(jian)設(she)(she)中(zhong)所有(you)相關設(she)(she)備的容量，從(cong)而降低(di)電網建(jian)設(she)(she)中(zhong)的投資。功率因數在0.7左右的系(xi)(xi)統(tong)，由于合(he)理的補償可使系(xi)(xi)統(tong)電流下降30%，即提高(gao)發電廠、變配(pei)電設(she)(she)施30%的帶(dai)載能(neng)力。
如果變(bian)(bian)(bian)壓器(qi)(qi)(qi)及線(xian)路小容(rong)(rong)量(liang)不足(zu)時(shi)，可(ke)(ke)以通過(guo)安(an)(an)裝無(wu)(wu)功(gong)補償裝置(zhi)的(de)(de)方法(fa)解決。安(an)(an)裝無(wu)(wu)功(gong)補償裝置(zhi)可(ke)(ke)以使(shi)無(wu)(wu)功(gong)功(gong)率就地平(ping)衡(heng)，從(cong)而減小流過(guo)線(xian)路及變(bian)(bian)(bian)壓器(qi)(qi)(qi)的(de)(de)電流，減緩導線(xian)及變(bian)(bian)(bian)壓器(qi)(qi)(qi)的(de)(de)*緣老(lao)化速度(du)，延長使(shi)用(yong)壽命。同時(shi)可(ke)(ke)以釋放變(bian)(bian)(bian)壓器(qi)(qi)(qi)及線(xian)路的(de)(de)容(rong)(rong)量(liang)，增加變(bian)(bian)(bian)壓器(qi)(qi)(qi)及線(xian)路帶負荷能力。如，有一臺100KVA變(bian)(bian)(bian)壓器(qi)(qi)(qi)，目(mu)前負載(zai)率為85%，COSΦ=0.7。如果加裝無(wu)(wu)功(gong)補償設備，可(ke)(ke)使(shi)變(bian)(bian)(bian)壓器(qi)(qi)(qi)釋放30%的(de)(de)帶載(zai)量(liang)，用(yong)戶可(ke)(ke)在變(bian)(bian)(bian)壓器(qi)(qi)(qi)不增容(rong)(rong)的(de)(de)情況(kuang)下，增加負載(zai)，進(jin)行擴大生產。
4、改良電壓質量
由(you)于系統存在的大(da)量(liang)感性(xing)負載將造成供(gong)電(dian)線(xian)路壓降，尤(you)其(qi)在供(gong)電(dian)線(xian)路末端更為嚴(yan)重，通過合(he)理(li)的補償可以合(he)理(li)的緩和(he)線(xian)路壓降，改(gai)良電(dian)能質量(liang)。
線路中的電壓損(sun)失的計(ji)算(suan)公式如下：
式中：
P—— 有功功率，kW
U—— 額定(ding)電壓，kV
R—— 線路(lu)總電阻，Ω
Q—— 無功功率，kVar
Xl—— 線路感抗，Ω
由(you)于系統的(de)感抗遠遠大(da)(da)于阻抗，從上式中可以看到,無(wu)功的(de)變化會引起電(dian)壓產生(sheng)很大(da)(da)的(de)變化。當線路中，無(wu)功功率(lv)Q減小以后，電(dian)壓損失也就減少了(le)。
對(dui)于供電(dian)線(xian)路末端(duan)電(dian)壓一般較低，可通過增加無功(gong)補(bu)償裝置來提升線(xian)路末端(duan)電(dian)壓，使用記(ji)設備安(an)全可靠運行。
另一方面，隨著工業的(de)(de)發展，大(da)量(liang)的(de)(de)自控設備(bei)及非線(xian)性負(fu)載的(de)(de)使用(yong)，使大(da)量(liang)諧(xie)波在供配(pei)電網(wang)絡中的(de)(de)流(liu)動，污染(ran)電網(wang)。通過合(he)理的(de)(de)配(pei)置補償濾波設備(bei)，治理或大(da)幅度降低諧(xie)波對供電系(xi)統和用(yong)電設備(bei)的(de)(de)影響是改良電能質量(liang)的(de)(de)主(zhu)要手段之一。
電(dian)能質量(liang)問題隨(sui)著新(xin)型電(dian)力系統的興起(qi)，必然要面臨很多電(dian)能質量(liang)相(xiang)關問題，以下幾類問題值得進(jin)一步了解、熟悉、探索：
① 諧振(zhen)問題分析，什么是諧振(zhen)？
② 什么(me)現(xian)(xian)場經常會(hui)出現(xian)(xian)濾波(bo)器(qi)損壞現(xian)(xian)象(xiang)？
③ 濾波器(qi)就(jiu)地補(bu)償和(he)集中補(bu)償的(de)區別？
④ 要求諧波治(zhi)理到(dao)5%，如何去理解(jie)？
⑤ 加裝濾波器(qi)到(dao)底能不(bu)能起到(dao)“節能”的作用？
⑥ 儲能、光伏、風電等電力電子器件的并網，對電能質(zhi)量的影(ying)響如(ru)何？
⑦ 微電網系統對電能質量(liang)的需求(qiu)是否重要？
⑧ 。。。
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