Lub transformer yog ib yam khoom siv uas siv lub hauv paus ntsiab lus ntawm electromagnetic induction los hloov hloov tam sim no voltage. Nws cov khoom tseem ceeb yog thawj kauj, theem ob, thiab cov tub ntxhais hlau (magnetic core). Hauv cov khoom siv hluav taws xob thiab hluav taws xob hluav taws xob, nws feem ntau yog siv rau theem voltage - nce / kauj ruam - down, impedance matching, thiab kev ruaj ntseg cais. Hauv cov tshuab hluav taws xob, txawm hais tias lub kauj txav mus los ntawm qhov chaw sib nqus los yog qhov chaw sib nqus txav los ntawm lub kauj vab, lub zog hluav taws xob yog induced hauv lub kauj. Nyob rau hauv ob qho tib si, tus nqi ntawm magnetic flux tseem tsis hloov, tab sis tus naj npawb ntawm magnetic fluxes txuas rau lub kauj hloov; qhov no yog lub hauv paus ntsiab lus ntawm kev sib nrig sib induction. Transformer yog ib yam khoom siv hluav taws xob sib nqus induction los hloov voltage, tam sim no, thiab impedance.
Transformers tuaj yeem faib ua raws li lawv daim ntawv thov raws li hauv qab no: faib transformers, fais fab transformers, tag nrho kaw transformers, ua ke transformers, qhuav-hom transformers, roj-immersed transformers, ib zaug-the transformers, hluav taws xob rauv transformers, rectifier transformers, reactors, anti{3}} cuam tshuam transformers}, lub thawv transformers, transformers, siab - tam sim no transformers, thiab excitation transformers, thiab lwm yam.