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磁耦合在磨煤機上的應用
發電廠廠用電動機及磨煤機是發電機組的配套動力設備,它在保證發電機組安全穩定運行中有著極其重要的作用。由於風機 、磨煤機類設備轉動部分自重較大,大功率風機葉輪轉子均支撐在軸瓦上,靜摩擦因數較大,因此風機 、磨煤機類設備為大慣量啟動設備,其驅動電機的啟動為帶載啟動。帶載啟動帶來得直接危害是:
1. 工gong作zuo機ji傳chuan遞di給gei電dian動dong機ji的de需xu克ke服fu的de轉zhuan矩ju超chao過guo了le電dian動dong機ji的de啟qi動dong轉zhuan矩ju,造zao成cheng電dian機ji滿man載zai啟qi動dong,甚shen至zhi超chao載zai啟qi動dong,啟qi動dong電dian流liu較jiao大da,對dui電dian網wang及ji電dian機ji的de衝chong擊ji大da,造zao成cheng電dian動dong機ji損sun壞huai(易斷籠條)。
2. 由(you)於(yu)電(dian)動(dong)機(ji)從(cong)零(ling)速(su)開(kai)始(shi)大(da)轉(zhuan)矩(ju)啟(qi)動(dong),機(ji)械(xie)部(bu)分(fen)無(wu)緩(huan)衝(chong)時(shi)間(jian),對(dui)機(ji)械(xie)部(bu)分(fen)造(zao)成(cheng)衝(chong)擊(ji)載(zai)荷(he),這(zhe)樣(yang)造(zao)成(cheng)磨(mo)煤(mei)機(ji)大(da)小(xiao)齒(chi)圈(quan)容(rong)易(yi)損(sun)壞(huai)。這(zhe)些(xie)都(dou)直(zhi)接(jie)影(ying)響(xiang)到(dao)設(she)備(bei)的(de)長(chang)周(zhou)期(qi)運(yun)行(xing)
改進傳動係統。使電動機近似空載啟動。是保證設備長周期運行的重要措施。實現電動機的軟啟動,其方式主要有電氣及機械2大類。對低壓380Vdiandongji,kepeizhidianqiruanqidongqi,duigaoyadianjiyibancaiyongjixiefangshi,tongchangweiyeliouheqiheruanqidonganquanlianzhouqi。youyuruanqidonganquanlianzhouqiqizhiliangqing,chicunxiao,yishishigaizao,weihugongzuoshao,yizuoweishebeiruanqidongdeshouxuan。
軟ruan啟qi動dong安an全quan聯lian軸zhou器qi通tong過guo鋼gang球qiu的de離li心xin壓ya力li產chan生sheng的de摩mo擦ca力li傳chuan遞di轉zhuan矩ju,通tong常chang將jiang軟ruan啟qi動dong安an全quan聯lian軸zhou器qi裝zhuang在zai傳chuan動dong鏈lian的de高gao速su端duan。當dang原yuan動dong機ji啟qi動dong時shi,由you於yu轉zhuan速su很hen低di,離li心xin力li很hen小xiao,其qi產chan生sheng的de摩mo擦ca力li也ye很hen小xiao,聯lian軸zhou器qi打da滑hua,主zhu動dong側ce隨sui電dian動dong機ji旋xuan轉zhuan,被bei動dong側ce靜jing止zhi,電dian動dong機ji為wei近jin似si空kong載zai啟qi動dong。隨sui著zhe轉zhuan速su的de增zeng加jia,摩mo擦ca力li逐zhu漸jian增zeng大da,聯lian軸zhou器qi的de被bei動dong側ce帶dai動dong工gong作zuo機ji開kai始shi旋xuan轉zhuan,直zhi到dao與yu主zhu動dong側ce同tong步bu旋xuan轉zhuan,電dian動dong機ji的de整zheng個ge啟qi動dong過guo程cheng是shi一yi個ge平ping穩wen的de逐zhu漸jian加jia載zai的de過guo程cheng,實shi現xian了le電dian動dong機ji的de“軟”啟動,改變了普通聯軸器聯接時的“硬”啟動方式。
當工作機過載或卡死時,由於轉矩超過了設計摩擦力可傳遞的轉矩,聯軸器打滑,防止了機械部件的損壞及電機的燒毀。
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