高壓(ya)發電機
發(fa)電(dian)(dian)(dian)機(ji)組(zu)(zu)是(shi)由同步發(fa)電(dian)(dian)(dian)機(ji)、驅動(dong)機(ji)械、控(kong)制及附屬(shu)裝置構成一體的(de)(de)(de)發(fa)電(dian)(dian)(dian)設備(bei)。現(xian)代數據、通信等(deng)中(zhong)(zhong)心的(de)(de)(de)不間斷供電(dian)(dian)(dian)系(xi)統廣泛地采用中(zhong)(zhong)、大功率的(de)(de)(de)柴油(you)發(fa)電(dian)(dian)(dian)機(ji)組(zu)(zu)作為(wei)市電(dian)(dian)(dian)的(de)(de)(de)備(bei)用電(dian)(dian)(dian)源。它(ta)們額定輸出的(de)(de)(de)線電(dian)(dian)(dian)壓是(shi)400V、相電(dian)(dian)(dian)壓230V，這在(zai)我國(guo)輸電(dian)(dian)(dian)網體制中(zhong)(zhong)屬(shu)于二(er)次(ci)配(pei)電(dian)(dian)(dian)網電(dian)(dian)(dian)壓范疇，即(ji)低壓區(qu)段。這些柴油(you)發(fa)電(dian)(dian)(dian)機(ji)組(zu)(zu)亦可稱為(wei)低壓發(fa)電(dian)(dian)(dian)組(zu)(zu)。 高壓發(fa)電(dian)(dian)(dian)機(ji)組(zu)(zu)與低壓發(fa)電(dian)(dian)(dian)機(ji)組(zu)(zu)的(de)(de)(de)基本工作原理(li)是(shi)一樣的(de)(de)(de)。
一(yi)般都是由柴油發(fa)(fa)(fa)動(dong)機(ji)(ji)帶(dai)動(dong)同(tong)(tong)(tong)步發(fa)(fa)(fa)電機(ji)(ji)在(zai)附屬裝置(zhi)和的(de)(de)配(pei)合下共同(tong)(tong)(tong)工作發(fa)(fa)(fa)出(chu)電力(li)。低(di)壓發(fa)(fa)(fa)電機(ji)(ji)組輸出(chu)功率在(zai)十幾到幾千kVA，高(gao)壓發(fa)(fa)(fa)電機(ji)(ji)組的(de)(de)輸出(chu)功率大都在(zai)一(yi)千kVA以上。還有少量的(de)(de)高(gao)壓發(fa)(fa)(fa)電機(ji)(ji)組采(cai)用(yong)了燃氣輪機(ji)(ji)帶(dai)動(dong)同(tong)(tong)(tong)步發(fa)(fa)(fa)電機(ji)(ji)。但無論采(cai)用(yong)什么類型(xing)的(de)(de)發(fa)(fa)(fa)動(dong)機(ji)(ji)作為驅動(dong)機(ji)(ji)械，它們的(de)(de)主軸轉(zhuan)速都應該(gai)設定(ding)在(zai)1500轉(zhuan)/min。這是為了確保(bao)三相同(tong)(tong)(tong)步發(fa)(fa)(fa)電機(ji)(ji)在(zai)它們的(de)(de)帶(dai)動(dong)下能夠發(fa)(fa)(fa)出(chu)符合規定(ding)的(de)(de)每秒(miao)鐘(zhong)50Hz的(de)(de)交流電。
同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機轉(zhuan)(zhuan)子(zi)(zi)上的(de)(de)(de)(de)(de)繞(rao)(rao)(rao)組(zu)線(xian)圈通(tong)以直(zhi)流(liu)電(dian)(dian)(dian)(dian)流(liu)后產生直(zhi)流(liu)轉(zhuan)(zhuan)子(zi)(zi)磁(ci)場(chang)，它的(de)(de)(de)(de)(de)強弱用磁(ci)通(tong)Φ表示。當轉(zhuan)(zhuan)子(zi)(zi)被(bei)發(fa)(fa)動(dong)機帶(dai)動(dong)旋(xuan)轉(zhuan)(zhuan)時，轉(zhuan)(zhuan)子(zi)(zi)的(de)(de)(de)(de)(de)磁(ci)場(chang)在(zai)旋(xuan)轉(zhuan)(zhuan)中(zhong)切(qie)割嵌在(zai)同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機定(ding)子(zi)(zi)內的(de)(de)(de)(de)(de)繞(rao)(rao)(rao)組(zu)(導線(xian)繞(rao)(rao)(rao)一(yi)圈稱為(wei)一(yi)匝(za)。每個(ge)繞(rao)(rao)(rao)組(zu)內有(you)N匝(za)線(xian)圈)，則繞(rao)(rao)(rao)組(zu)兩(liang)端產生感(gan)應(ying)電(dian)(dian)(dian)(dian)動(dong)勢E。轉(zhuan)(zhuan)子(zi)(zi)磁(ci)通(tong)Φ越(yue)強，定(ding)子(zi)(zi)繞(rao)(rao)(rao)組(zu)線(xian)圈匝(za)數N越(yue)多，則產生的(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)壓(ya)越(yue)高。同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機共(gong)有(you)三個(ge)(三相)定(ding)子(zi)(zi)繞(rao)(rao)(rao)組(zu)，每個(ge)繞(rao)(rao)(rao)組(zu)的(de)(de)(de)(de)(de)感(gan)應(ying)電(dian)(dian)(dian)(dian)動(dong)勢E的(de)(de)(de)(de)(de)有(you)效(xiao)值為(wei)：E=4.44ΦfNK 式中(zhong)，f是同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機輸出(chu)(chu)電(dian)(dian)(dian)(dian)壓(ya)的(de)(de)(de)(de)(de)頻(pin)率50Hz，K是定(ding)子(zi)(zi)繞(rao)(rao)(rao)組(zu)內整距線(xian)圈與短距線(xian)圈的(de)(de)(de)(de)(de)數量比，稱為(wei)節距因(yin)數，通(tong)常K≤1。可見，要想讓同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機發(fa)(fa)出(chu)(chu)更(geng)高的(de)(de)(de)(de)(de)電(dian)(dian)(dian)(dian)壓(ya)，雙(shuang)管齊(qi)下地增(zeng)大轉(zhuan)(zhuan)子(zi)(zi)磁(ci)場(chang)的(de)(de)(de)(de)(de)磁(ci)通(tong)Φ及(ji)增(zeng)加定(ding)子(zi)(zi)繞(rao)(rao)(rao)組(zu)內的(de)(de)(de)(de)(de)線(xian)圈匝(za)數N就可以做(zuo)到。高壓(ya)同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機就是依此技術(shu)理念制造(zao)的(de)(de)(de)(de)(de)。隨著電(dian)(dian)(dian)(dian)機制造(zao)技術(shu)的(de)(de)(de)(de)(de)逐步提高以及(ji)新材料(liao)的(de)(de)(de)(de)(de)不斷涌現，現代高壓(ya)同(tong)(tong)(tong)步發(fa)(fa)電(dian)(dian)(dian)(dian)機的(de)(de)(de)(de)(de)技術(shu)性能已趨于(yu)完善。
半個多世紀以(yi)來，高壓(ya)發電(dian)(dian)機組已從(cong)軍工領域(yu)逐步向國民經濟的(de)其他部門普及，主要原因是(shi)它的(de)高壓(ya)同步發電(dian)(dian)機(以(yi)下(xia)(xia)簡稱高壓(ya)發電(dian)(dian)機或發電(dian)(dian)機)以(yi)下(xia)(xia)性能(neng)特點。
1、輸(shu)(shu)出(chu)電(dian)(dian)壓(ya)(ya)(ya)高(gao)(gao) 按照相關的標準，高(gao)(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)組額(e)(e)定(ding)輸(shu)(shu)出(chu)的線(xian)(xian)電(dian)(dian)壓(ya)(ya)(ya)——實際上就是高(gao)(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)輸(shu)(shu)出(chu)的線(xian)(xian)電(dian)(dian)壓(ya)(ya)(ya)10kV。低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)組額(e)(e)定(ding)輸(shu)(shu)出(chu)線(xian)(xian)電(dian)(dian)壓(ya)(ya)(ya)——實際上是低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)輸(shu)(shu)出(chu)的線(xian)(xian)電(dian)(dian)壓(ya)(ya)(ya)400V。高(gao)(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)比低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)機(ji)(ji)的輸(shu)(shu)出(chu)電(dian)(dian)壓(ya)(ya)(ya)高(gao)(gao)25倍。
2、輸出(chu)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)小(xiao)(xiao) 發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)的供(gong)(gong)電(dian)(dian)(dian)(dian)(dian)(dian)能(neng)力用其額(e)定(ding)(ding)(ding)容量SH=1.73UHIH表(biao)征。它定(ding)(ding)(ding)義(yi)了額(e)定(ding)(ding)(ding)功(gong)(gong)率(lv)(lv)(lv)因數(shu)為(wei)0.8的發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)在(zai)(zai)(zai)(zai)向負載饋送(song)額(e)定(ding)(ding)(ding)線(xian)電(dian)(dian)(dian)(dian)(dian)(dian)壓(ya)(ya)(ya)為(wei)UH的額(e)定(ding)(ding)(ding)線(xian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)是IH時，可供(gong)(gong)出(chu)的額(e)定(ding)(ding)(ding)視(shi)(shi)在(zai)(zai)(zai)(zai)功(gong)(gong)率(lv)(lv)(lv)SH。 設低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)可輸出(chu)的額(e)定(ding)(ding)(ding)視(shi)(shi)在(zai)(zai)(zai)(zai)功(gong)(gong)率(lv)(lv)(lv)為(wei)SHO，另一臺高(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)可輸出(chu)的額(e)定(ding)(ding)(ding)視(shi)(shi)在(zai)(zai)(zai)(zai)功(gong)(gong)率(lv)(lv)(lv)大小(xiao)(xiao)同(tong)樣是SHO。則有(you)(you)(高(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji))1.73UHGIHG=1.73UHDIHD(低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji))。此時高(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)輸出(chu)的線(xian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)IHG與(yu)低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)輸出(chu)線(xian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)IHD之(zhi)比為(wei)可見，輸出(chu)同(tong)樣的額(e)定(ding)(ding)(ding)視(shi)(shi)在(zai)(zai)(zai)(zai)功(gong)(gong)率(lv)(lv)(lv)，高(gao)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)所(suo)供(gong)(gong)出(chu)的線(xian)電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)只是低(di)壓(ya)(ya)(ya)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)(dian)機(ji)的二十五分(fen)之(zhi)一。電(dian)(dian)(dian)(dian)(dian)(dian)流(liu)(liu)小(xiao)(xiao)，電(dian)(dian)(dian)(dian)(dian)(dian)能(neng)在(zai)(zai)(zai)(zai)輸電(dian)(dian)(dian)(dian)(dian)(dian)線(xian)路上的損耗(hao)就(jiu)小(xiao)(xiao)，而且(qie)輸配電(dian)(dian)(dian)(dian)(dian)(dian)線(xian)纜(lan)的橫(heng)截面積(ji)就(jiu)可小(xiao)(xiao)很多，這有(you)(you)利(li)于遠(yuan)距離輸電(dian)(dian)(dian)(dian)(dian)(dian)，還可以節省銅材。
3、轉(zhuan)子磁(ci)(ci)(ci)場強 高(gao)壓(ya)發電(dian)(dian)(dian)(dian)(dian)機(ji)通(tong)過增大(da)轉(zhuan)子繞(rao)組線圈的(de)匝數和輸(shu)入線圈的(de)直流(liu)(liu)(liu)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)(叫作勵磁(ci)(ci)(ci)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu))可得到(dao)比(bi)低壓(ya)發電(dian)(dian)(dian)(dian)(dian)機(ji)強幾到(dao)幾十倍(bei)的(de)轉(zhuan)子磁(ci)(ci)(ci)場與磁(ci)(ci)(ci)通(tong)Φ。勵磁(ci)(ci)(ci)電(dian)(dian)(dian)(dian)(dian)流(liu)(liu)(liu)來自由旋轉(zhuan)整流(liu)(liu)(liu)器(qi)(qi)、無刷勵磁(ci)(ci)(ci)發電(dian)(dian)(dian)(dian)(dian)機(ji)、自動(dong)電(dian)(dian)(dian)(dian)(dian)壓(ya)調節器(qi)(qi)所構成的(de)發電(dian)(dian)(dian)(dian)(dian)機(ji)自動(dong)電(dian)(dian)(dian)(dian)(dian)壓(ya)調控系統(tong)。該系統(tong)把轉(zhuan)子磁(ci)(ci)(ci)場磁(ci)(ci)(ci)通(tong)Φ與高(gao)壓(ya)發電(dian)(dian)(dian)(dian)(dian)機(ji)輸(shu)出電(dian)(dian)(dian)(dian)(dian)壓(ya)U以負反(fan)饋邏輯聯動(dong)起來，若因負載(zai)變動(dong)引起U下降，則調控系統(tong)使(shi)Φ增強而(er)導致U上升。反(fan)之亦然。它不僅向轉(zhuan)子繞(rao)組提供很(hen)大(da)的(de)勵磁(ci)(ci)(ci) 產生強勢的(de)磁(ci)(ci)(ci)場與磁(ci)(ci)(ci)通(tong)Φ，為發電(dian)(dian)(dian)(dian)(dian)機(ji)輸(shu)出高(gao)電(dian)(dian)(dian)(dian)(dian)壓(ya)創造了條件，而(er)且還自動(dong)地穩定高(gao)壓(ya)發電(dian)(dian)(dian)(dian)(dian)機(ji)的(de)輸(shu)出電(dian)(dian)(dian)(dian)(dian)壓(ya)。