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        電力變壓器安裝工藝

        2014/1/21 8:32:56      點擊:
        電力變壓器 安裝工藝變壓器英文名稱(transformer) [trAns'fC:mE(r),tra:-]。
        變壓器是變換交流電壓、電流和阻抗的器件,當初級線圈中通有交流電流時,鐵芯(或磁芯)中便產生交流磁通,使次級線圈中感應出電壓(或電流)。變壓器由鐵芯(或磁芯)和線圈組成,線圈有兩個或兩個的繞組,其中接電源的繞組叫初級線圈,其余的繞組叫次級線圈。變壓器是一種常見的電子元件和電氣設備, 可用來把某種數(shù)值的交變電壓變換為同頻率的另一數(shù)值的交變電壓,也可以改變交流電的數(shù)值及變換阻抗或改變相位或變換頻率。為什么需要電力變壓器。發(fā)電廠欲將P=sqrt(3)*UIcosφ的電功率輸送到用電的區(qū)域,在P、cosφ為一定值時,若采用的電壓愈高,則輸電線路中的電流愈小,因而可以減少輸電線路上的損耗,節(jié)約導電材料。所以遠距離輸電采用高電壓是最為經濟的。我國交流輸電的電壓最高已達500kV。這樣高的電壓,無論從發(fā)電機的安全運行方面或是從制造成本方面考慮,都不允許由發(fā)電機直接生產。發(fā)電機的輸出電壓一般3.15kV6.3kV、10.5 kV、 15.75 kV等幾種,因此必須用升壓變壓器將電壓升高才能遠距離輸送。為什么需要配電變壓器:電能輸送到用電區(qū)域后,為了適應用電設備的電壓要求,還需通過各級變電站(所)利用變壓器將電壓降低為各類電器所需要的電壓值。
        在用電方面,多數(shù)用電器所需電壓是380V、220V或36 V,少數(shù)電機也采用3kV、6kV等。
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