The working principle of inductors is based on Faraday's law of electromagnetic induction. When an electric current passes through an inductor, a magnetic field is created around it. This magnetic field prevents further changes in the current, creating an electromotive force that is the opposite of the original current. This electromotive force prevents the current from changing, causing the amplitude of the current to gradually decrease. This is the self-inductance phenomenon of inductance.
At the same time, when the current passes through the inductor, there is also a mutual inductance phenomenon. Mutual inductance is the phenomenon that when two coils are close to each other, the current change in one coil will induce an electromotive force in the other coil. The size of this electromotive force is related to the relative position of the two coils, the number of turns, and other factors.
The main functions of inductors are:
Stored energy
Inductors have the property of storing energy. When an electric current passes through an inductor, a magnetic field is established and the electrical energy is converted to magnetic energy and stored. This energy storage characteristic enables the inductor to play a role in smoothing the current in the circuit, avoiding voltage fluctuations.
Filtering
The inductor and capacitor can be used together to form a filter circuit. The filter circuit can filter out the harmonic components in the circuit and improve the stability of the circuit. In the power supply circuit, the filter can reduce the influence of the internal resistance of the power supply on the load and improve the efficiency of the power supply.
Resist AC and pass DC
For direct current, the inductor is equivalent to conduction; For alternating current, the inductor has a hindering effect on it, and the higher the frequency of alternating current, the greater the hindering effect of the inductor on it.
Tune in
The main function of the inductor is to tune the circuit so that the operating frequency of the amplifier is stable at a certain frequency. By adjusting the inductance, the current and voltage in the circuit can be changed to achieve the stability and reliability of the circuit.
Resonance
The inductor can form a resonant circuit with the capacitor to generate high-frequency resonance and achieve the purpose of stabilizing the current.
Oscillation
The inductor can be used with capacitors, resistors and other components to form an oscillating circuit. The oscillating circuit can generate high frequency signal, which is widely used in wireless communication, radar and other fields.
Delay effect
The inductor has a certain delay effect on the current. This delay characteristic makes the inductor can play the role of delay switch in some circuits and realize the delay control of the circuit.
Screen signals
Inductors can be used to screen signals, allowing only the required signals to pass through and suppressing interference from other signals.
Filter the noise
The inductor can filter the noise, isolate the interference noise in the circuit where the inductor is located, and avoid the interference noise affecting the normal operation of other circuits.