变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)（Transformer）是(shi)(shi)利用电(dian)磁感应的(de)原理来改变(bian)(bian)(bian)(bian)(bian)交流电(dian)压的(de)装(zhuang)置，主要(yao)构件是(shi)(shi)初级线(xian)圈、次级线(xian)圈和铁心（磁芯）。主要(yao)功(gong)能有：电(dian)压变(bian)(bian)(bian)(bian)(bian)换(huan)、电(dian)流变(bian)(bian)(bian)(bian)(bian)换(huan)、阻(zu)抗(kang)变(bian)(bian)(bian)(bian)(bian)换(huan)、隔离、稳压（磁饱和变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)）等(deng)。按(an)用途(tu)可以分(fen)为：配(pei)电(dian)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、电(dian)力变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、全密封(feng)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、组合式(shi)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、干(gan)式(shi)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、油浸(jin)式(shi)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、单相(xiang)变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、电(dian)炉变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)、整流变(bian)(bian)(bian)(bian)(bian)压器(qi)(qi)等(deng)。

节能(neng)电炉(lu)(lu)(lu)(lu)在升温(wen)(wen)过程中发热体电阻(zu)的(de)改(gai)变(bian)太(tai)大(da)，所以须要在节能(neng)电炉(lu)(lu)(lu)(lu)和电力网(wang)之(zhi)间设备一台(tai)电阻(zu)炉(lu)(lu)(lu)(lu)变(bian)压器，以降(jiang)低和调度电炉(lu)(lu)(lu)(lu)的(de)输(shu)入电压。电炉(lu)(lu)(lu)(lu)变(bian)压器是用(yong)(yong)于高温(wen)(wen)电炉(lu)(lu)(lu)(lu)和节能(neng)电炉(lu)(lu)(lu)(lu)供电的(de)专(zhuan)用(yong)(yong)变(bian)压器。

容量大(da)，结构凌乱(luan)，技术要(yao)(yao)求较高。其副边(bian)电(dian)压低，个别从数十伏到数百伏，并需要(yao)(yao)能(neng)在较大(da)范(fan)围内(nei)调度；副边(bian)电(dian)流常常达数千至数万安。别的在钢铁练习中,电(dian)炉(lu)(lu)(lu)变压器(qi)(qi)是指专为各(ge)种(zhong)高温(wen)电(dian)炉(lu)(lu)(lu)供给电(dian)源的变压器(qi)(qi)。工业(ye)用(yong)电(dian)炉(lu)(lu)(lu)变压器(qi)(qi)大(da)致(zhi)可分为3类:电(dian)阻(zu)炉(lu)(lu)(lu)变压器(qi)(qi)、电(dian)弧炉(lu)(lu)(lu)变压器(qi)(qi)和(he)觉得炉(lu)(lu)(lu)变压器(qi)(qi)。电(dian)阻(zu)炉(lu)(lu)(lu)变压器(qi)(qi)用(yong)于机械零(ling)件加热、热处理、粉末冶金(jin)烧结、有色金(jin)属(shu)熔(rong)炼等的电(dian)阻(zu)炉(lu)(lu)(lu)和(he)盐浴炉(lu)(lu)(lu)。因为其发(fa)热体的电(dian)阻(zu)太小(xiao)。

变(bian)压器是变(bian)换(huan)交(jiao)流(liu)(liu)(liu)(liu)电(dian)压、交(jiao)变(bian)电(dian)流(liu)(liu)(liu)(liu)和(he)阻抗的器件(jian)，当初级线圈中通有交(jiao)流(liu)(liu)(liu)(liu)电(dian)流(liu)(liu)(liu)(liu)时，铁(tie)芯(xin)（或磁芯(xin)）中便(bian)产生交(jiao)流(liu)(liu)(liu)(liu)磁通，使次(ci)级线圈中感(gan)应(ying)出电(dian)压（或电(dian)流(liu)(liu)(liu)(liu)）。

变压器由铁芯（或磁芯）和线(xian)圈(quan)组成，线(xian)圈(quan)有(you)两(liang)个(ge)(ge)或两(liang)个(ge)(ge)以上的(de)绕组，其中接电(dian)源的(de)绕组叫初级(ji)线(xian)圈(quan)，其余的(de)绕组叫次级(ji)线(xian)圈(quan)。