变压器（Transformer）是利用电磁感应的原理来改变交流电压的装置，主要构件是初级线圈、次级线圈和铁芯（磁芯）。主要功能有：电压变换、电流变换、阻抗变换、隔离、稳压（磁饱和变压器）等。按用途可以分为：电力变压器和特殊变压器（电炉变、整流变、工频试验变压器、调压器、矿用变、音频变压器、中频变压器、高频变压器、冲击变压器、仪用变压器、电子变压器、电抗器、互感器等）。电路符号常用T当作编号的开头.例: T01, T201等。(A transformer (Transformer) is a device that uses the principle of electromagnetic induction to change the AC voltage. The main components are the primary coil, the secondary coil and the iron core (core). The main functions are: voltage transformation, current transformation, impedance transformation, isolation, voltage stabilizing (magnetic saturation transformer) and so on. It can be divided into power transformers and special transformers (electric transformer, rectifier and transformer, power frequency transformer, voltage regulator, mine change, audio transformer, intermediate frequency transformer, high-frequency transformer, shock transformer, transformer, transformer, reactor, intersenser, etc.). Circuit symbols usually use T as the beginning of numbering. Examples: T01, T201 and so on.)