开关变压器的特性有哪些？工作原理是什么？开关变压器组装用什么胶水粘接？

开关变压器

开关稳压电源电路中使用的开关变压器，属于脉冲电路用振荡变压器。其主要作用是向负载电路提供能量（即为整机各电路提供工作电压），实现输入、输出电路之间的隔离。

开关变压器二次（次级）侧有多组电能释放绕组，可产生多路脉冲电压，经整流、滤波后供给后级各有关电路。

单激式变压器开关电源等效成如图2所示电路，其中我们把直流输入电压通过控制开关通、断的作用，看成是一序列直流脉冲电压，即单极性脉冲电压，直接给开关变压器供电。这里我们特别把变压器称为开关变压器，以表示图1所示电路与一般电源变压器电路在工作原理方面还有区别的。

在一般的电源变压器电路中，当电源变压器两端的输入电压为0时，表示输入端是短路的，因为电源内阻可以看作为0；而在开关变压器电路中，当开关变压器两端的输入电压为0时，表示输入端是开路的，因为电源内阻可以看作为无限大。

此类型的变压器粘接固定一般推荐选用单组份的环氧树脂胶粘剂进行固定，相关参数如下供参考

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外观及物性

外观                 粘稠膏状体                  

颜色                 黑色、灰色、白色                

比重（25℃）  1.45-1.55                  

粘度 （25℃）  55000-75000 cps

保存期限          25度2个月，5度3个月      

包装                1KG或5KG         

固化条件：      120℃/1-1.5小时

Switch transformer

The switching transformer used in the switching power supply circuit belongs to the oscillation transformer used in the pulse circuit. Its main function is to provide energy to the load circuit (that is, to provide working voltage for each circuit of the whole machine) and realize the isolation between the input and output circuits.

The secondary (secondary) side of the switching transformer has several groups of power release windings, which can generate multi-channel pulse voltage and supply it to the relevant circuits of the later stage after rectification and filtering.

The single excitation transformer switching power supply is equivalent to the circuit shown in Figure 2, in which we regard the DC input voltage as a sequence of DC pulse voltage, that is, unipolar pulse voltage, which directly supplies power to the switching transformer by controlling the switch on and off. Here we specially call the transformer switch transformer to show that the circuit shown in Figure 1 is different from the general power transformer circuit in working principle.

In the general power transformer circuit, when the input voltage at both ends of the power transformer is 0, it means that the input end is short-circuit, because the internal resistance of the power supply can be regarded as 0; In the switch transformer circuit, when the input voltage at both ends of the switch transformer is 0, it means that the input end is open, because the internal resistance of the power supply can be regarded as infinite.