Inductor coil

High current power inductors is a device that works on the principle of electromagnetic induction. When a current flows through a wire, a certain electromagnetic field will be generated around the wire, and the conductor of this electromagnetic field will itself induction to the wire within the scope of this electromagnetic field. The effect on the wire itself that produces the electromagnetic field is called "self-inductance", that is, the changing current generated by the wire itself produces a changing magnetic field, which further affects the current in the wire; The effect on other wires in this electromagnetic field range is called mutual inductance. 

The electrical characteristics of shielded inductor or Inductor are the opposite of capacitors, "passing low frequency and blocking high frequency". High frequency signal through the inductor will encounter great resistance, it is difficult to pass; The resistance to low-frequency signals passing through it is relatively small, that is, low-frequency signals can pass through it more easily. The inductor coil has almost zero resistance to direct current. 

Resistance, capacitance and inductance, they will present a certain resistance to the flow of electrical signals in the circuit, this resistance we call "impedance". The impedance of the inductors for sale to the current signal uses the self-inductance of the coil. Inductor sometimes we refer to it simply as "inductor" or "coil", represented by the letter "L". When winding an inductor, the number of turns of the coil we generally call it the "number of turns" of the coil.