Inductor working principle  

 A passive component, which acts to suppress change of the current, the inductance is also often referred to as "AC resistance", which inhibits ER of functionality and storage capability of magnetic field energy the inductor is the most useful features; current through the inductor will A magnetic field is generated, and the change of the magnetic field induces a voltage in the opposite direction of the current generated. This characteristic of suppressing the current change is called the inductance value. The induced voltage at both ends of the inductor due to the current change can be defined as:         

                  V=L di/dt       

          In this way, the induced voltage is proportional to the inductance value and the current change speed.  

Image statement: pass DC; block AC

It mainly plays the role of energy storage and filtering in the circuit