During the measuring of the DC resistance of a transformer’s winding, the winding is equivalent to a resistance-inductance series circuit. Because power transformers often have big inductance but small resistance, they usually have big characteristic time.

在进行变压器绕组直流电阻的测量时，变压器绕组可以等效为一个由电阻、电感组成的串联电路。

By means of the ordinary differential theory,analytical expression of electric oscillation of the RLC series circuit equation is obtained. Electric oscillations of the system are analyzed.

通过伽辽金方法推导出了极板微梁系统的非线性振动方程,并求得了极板的吸合电压;应用常微分方程理论得到了RLC串联电路方程电振荡的解析表达式,分析了系统的电振荡特性。