变压器是变换交流电压、电流和阻抗的器件，变压器工作原理是利用电磁感应原理制成的静止用电器。它的分类有很多，按照不通用的作用可分为脉冲功率变压器、中周变压器、触发变压器、屏蔽变压器等等。变压器利用电磁感应原理，从一个电路向另一个电路传递电能或传输信号的一种电器，是电能传递或作为信号传输的重要元件。变压器是变换交流电压、电流和阻抗的器件，当初级线圈中通有交流电流时，铁芯（或磁芯）中便产生交流磁通，使次级线圈中感应出电压（或电流）。变压器由铁芯（或磁芯）和线圈组成，线圈有两个或两个以上的绕组，其中接电源的绕组叫初级线圈，其余的绕组叫次级线圈。
A transformer is a device for changing the AC voltage, current and impedance. The principle of the transformer is a static electric appliance made of the principle of electromagnetic induction. It has a lot of classification, which can be divided into pulse power transformer, middle and circumferential transformer, trigger transformer, shielding transformer and so on. A transformer that uses electromagnetic induction to transmit electric energy or transmit signals from one circuit to another is an important component of electric energy transmission or signal transmission. The transformer is the device transform AC voltage, current and impedance, when there is communication through the primary coil current, the core (or core) will be generated in the exchange flux, the secondary coil induces a voltage (or current). A transformer consists of an iron core or a magnetic coil. The coil has two or more than two windings. The winding of the power supply is called the primary coil, and the other winding is called the secondary coil.