一、工作原理
發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)(Generators)是(shi)指(zhi)將機(ji)(ji)(ji)械(xie)能(neng)(neng)(neng)轉換(huan)成(cheng)電(dian)(dian)(dian)(dian)(dian)能(neng)(neng)(neng)的(de)(de)機(ji)(ji)(ji)械(xie)設(she)備(bei),它(ta)由(you)水(shui)輪機(ji)(ji)(ji)、汽輪機(ji)(ji)(ji)、柴油機(ji)(ji)(ji)或其他動力機(ji)(ji)(ji)械(xie)驅(qu)動,將水(shui)流,氣流,燃(ran)(ran)料(liao)燃(ran)(ran)燒(shao)或原子核裂(lie)變(bian)產生的(de)(de)能(neng)(neng)(neng)量轉化為(wei)機(ji)(ji)(ji)械(xie)能(neng)(neng)(neng)傳給發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji),再由(you)發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)轉換(huan)為(wei)電(dian)(dian)(dian)(dian)(dian)能(neng)(neng)(neng)。發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)在(zai)工(gong)農業生產、國防、科技及日常生活中有(you)廣泛的(de)(de)用途。發(fa)(fa)電(dian)(dian)(dian)(dian)(dian)機(ji)(ji)(ji)的(de)(de)形式很多,但其工(gong)作原理都基于電(dian)(dian)(dian)(dian)(dian)磁(ci)感應定律和(he)電(dian)(dian)(dian)(dian)(dian)磁(ci)力定律。因(yin)此,其構造的(de)(de)一般原則是(shi):用適當的(de)(de)導磁(ci)和(he)導電(dian)(dian)(dian)(dian)(dian)材料(liao)構成(cheng)互(hu)相進行(xing)電(dian)(dian)(dian)(dian)(dian)磁(ci)感應的(de)(de)磁(ci)路(lu)(lu)和(he)電(dian)(dian)(dian)(dian)(dian)路(lu)(lu),以產生電(dian)(dian)(dian)(dian)(dian)磁(ci)功率,達到能(neng)(neng)(neng)量轉換(huan)的(de)(de)目的(de)(de)。
二、主要特性
工作特性:
表征同步發電機(ji)性(xing)能的(de)(de)主(zhu)要是空載(zai)特(te)(te)性(xing)和(he)負載(zai)運行特(te)(te)性(xing)。這些特(te)(te)性(xing)是用戶選用發電機(ji)的(de)(de)重要依據。
空載特性:
發電(dian)機(ji)不接負載時(shi),電(dian)樞電(dian)流(liu)為零,稱為空(kong)載運行。此時(shi)電(dian)機(ji)定子的(de)三相(xiang)(xiang)繞(rao)組只有勵(li)磁電(dian)流(liu)If感生出的(de)空(kong)載電(dian)動勢E0(三相(xiang)(xiang)對稱),其大(da)小隨If的(de)增大(da)而增加。但是,由于電(dian)機(ji)磁路(lu)鐵心有飽和現象,所以兩(liang)者不成正比。反映空(kong)載電(dian)動勢E0與勵(li)磁電(dian)流(liu)If關系的(de)曲線(xian)稱為同步發電(dian)機(ji)的(de)空(kong)載特(te)性。
電樞反應:
當(dang)發電(dian)機接上對稱負載后,電(dian)樞繞組中的(de)三相電(dian)流(liu)會產生另一個旋轉(zhuan)(zhuan)磁場,稱電(dian)樞反應(ying)磁場。其轉(zhuan)(zhuan)速正好與(yu)轉(zhuan)(zhuan)子的(de)轉(zhuan)(zhuan)速相等,兩(liang)者同步旋轉(zhuan)(zhuan)。
同步發電(dian)(dian)(dian)(dian)(dian)機的(de)(de)電(dian)(dian)(dian)(dian)(dian)樞(shu)(shu)反(fan)應(ying)磁場與(yu)轉子勵磁磁場均可近似地認為(wei)都按(an)正弦規律(lv)分(fen)布。它們(men)之間的(de)(de)空間相(xiang)位差(cha)取(qu)決(jue)于空載電(dian)(dian)(dian)(dian)(dian)動勢E0與(yu)電(dian)(dian)(dian)(dian)(dian)樞(shu)(shu)電(dian)(dian)(dian)(dian)(dian)流I之間的(de)(de)時間相(xiang)位差(cha)。電(dian)(dian)(dian)(dian)(dian)樞(shu)(shu)反(fan)應(ying)磁場還與(yu)負(fu)載情況有關(guan)。當(dang)發電(dian)(dian)(dian)(dian)(dian)機的(de)(de)負(fu)載為(wei)電(dian)(dian)(dian)(dian)(dian)感性時,電(dian)(dian)(dian)(dian)(dian)樞(shu)(shu)反(fan)應(ying)磁場起(qi)去磁作用(yong),會導致發電(dian)(dian)(dian)(dian)(dian)機的(de)(de)電(dian)(dian)(dian)(dian)(dian)壓降低;當(dang)負(fu)載呈(cheng)電(dian)(dian)(dian)(dian)(dian)容(rong)性時,電(dian)(dian)(dian)(dian)(dian)樞(shu)(shu)反(fan)應(ying)磁場起(qi)助磁作用(yong),會使發電(dian)(dian)(dian)(dian)(dian)機的(de)(de)輸出電(dian)(dian)(dian)(dian)(dian)壓升高。
負載運行特性:
主要(yao)指(zhi)外特性和調整(zheng)特性。外特性是當轉速為(wei)額定值(zhi)、勵(li)磁(ci)電(dian)流和負(fu)(fu)載功率因(yin)數(shu)(shu)為(wei)常(chang)數(shu)(shu)時,發(fa)電(dian)機(ji)端(duan)電(dian)壓(ya)U與負(fu)(fu)載電(dian)流I之間(jian)的(de)關(guan)系。調整(zheng)特性是轉速和端(duan)電(dian)壓(ya)為(wei)額定值(zhi)、負(fu)(fu)載功率因(yin)數(shu)(shu)為(wei)常(chang)數(shu)(shu)時,勵(li)磁(ci)電(dian)流If與負(fu)(fu)載電(dian)流I之間(jian)的(de)關(guan)系。
同步(bu)發電(dian)機的(de)(de)電(dian)壓變化率約為(wei)20~40%。一般工業和家用負載都要求電(dian)壓保持(chi)基本不變。為(wei)此,隨著(zhu)負載電(dian)流的(de)(de)增大,必須相應地調(diao)整勵磁電(dian)流。雖(sui)然調(diao)整特性(xing)的(de)(de)變化趨勢與外特性(xing)正(zheng)好(hao)相反,對于感性(xing)和純電(dian)阻性(xing)負載,它是(shi)上升(sheng)的(de)(de),而(er)在容性(xing)負載下,一般是(shi)下降(jiang)的(de)(de)。
三、注意事項
正確使(shi)用(yong)和維護發(fa)(fa)電(dian)機組(zu)可(ke)延(yan)長發(fa)(fa)電(dian)機組(zu)的使(shi)用(yong)壽(shou)命:
起動前的準備工作:
1、機房操(cao)作(zuo)(zuo)(zuo)人(ren)員應(ying)遵守安(an)全操(cao)作(zuo)(zuo)(zuo)規程,穿工作(zuo)(zuo)(zuo)服(fu)和(he)絕緣鞋,機組人(ren)員應(ying)分工明確;
2、檢查飛輪及發(fa)電(dian)機部分防欄桿罩(zhao)是(shi)否完好;
3、檢查各變速箱、離合器、調速器、油位、各緊固件等,確認完好(hao),油水溫度不低于20度時,方可(ke)起(qi)動;
4、將(jiang)各系統(tong)管(guan)路閘門(men)設置在“工作”位置;
5、檢查傳(chuan)動機構的(de)鏈接螺(luo)栓,并(bing)緊固好(hao);
6、將離(li)合器手柄壓(ya)力是否正常,超速(su)保(bao)險裝置是否定(ding)位;
7、檢查貯氣瓶壓力是(shi)否(fou)正常,超(chao)速保險裝置是(shi)否(fou)定(ding)位;
8、打(da)開打(da)氣泵的排污閥;
9、檢(jian)查循環水泵、機油(you)泵、燃油(you)泵是否正常;
10、將勵磁電阻(zu)置于最(zui)大的電阻(zu)位置,并將送電開關斷(duan)開。
起動和運行操作:
1、對于停機超(chao)過24h的(de)機組,須(xu)先打開試動(dong)閥(fa),并起動(dong)機油(you)泵(beng)。對于停機超(chao)過7天的(de)機組,應(ying)測量勵磁機及操作(zuo)電路(lu)的(de)絕緣電阻(zu),必(bi)須(xu)符合要求(qiu);
2、起動燃(ran)油泵,放出管路中的空氣,觀察電壓是否在規定的范圍內。若正常,方可進行(xing)正式起動;
3、察看起動電源的電壓(ya)是否符合要(yao)求。若電壓(ya)正常,按下起動按鈕等柴油發動機(ji)正常運行后即(ji)松開;
4、當柴油(you)發動(dong)機(ji)(ji)運轉后,觀察機(ji)(ji)油(you)壓(ya)力表的指示值(zhi),當升到規定值(zhi)以上(shang)時,停止機(ji)(ji)油(you)泵(beng),并關閉掃氣泵(beng)排污(wu)閥,穿好前(qian)離合(he)器螺釘(ding);
5、當(dang)發電(dian)機起動后(hou),即認(ren)為發電(dian)機及全部電(dian)氣設(she)備均已(yi)帶電(dian),人(ren)體不得接觸帶電(dian)部位;
6、發(fa)電機(ji)起動(dong)后,應(ying)逐(zhu)漸提高柴油發(fa)動(dong)機(ji)的轉(zhuan)速,并進行送電前的檢查;
7、逐漸調整柴油發動(dong)機(ji)的(de)轉速,但在(zai)調整時應注意觀察(cha)發電(dian)機(ji)運轉是否正常(chang)。正常(chang)時,集電(dian)環及換向器上(shang)的(de)電(dian)刷應無跳動(dong)、無冒火花現象、無異(yi)常(chang)響聲(sheng);
8、調整發電(dian)機輸(shu)出的電(dian)壓和頻(pin)率,其電(dian)壓值應穩定并達到(dao)380v+-10v,頻(pin)率應達到(dao)50Hz+-0.5Hz。
(圖文來源(yuan):網絡,版權(quan)歸原(yuan)作者所有,若有侵權(quan)請聯(lian)系刪除(chu))
Copyright© 2013-2023 上海連航機電科技有限公司 版權所有
地址:上海市寶山區滬太路1866號諾誠M7創意園B區211
電話 (Tel.):400-135-1288 傳真 (Fax):400-135-1288 郵箱 (E-mail):
 
|
掃(sao)描微信二維碼關注我們