Inductors are essential basic electronic components

Inductors are essential basic electronic components

Inductors are essential basic electronic components in electronic circuits, accounting for about 10% to 15% of the total amount of electronic components. With the development of the electronics industry, inductors are one of the most important components of the three passive components.

Definition of inductance: Inductance is the ratio of alternating magnetic flux generated in and around the conductor when alternating current passes through the conductor, and the magnetic flux of the conductor is the ratio of the current to the magnetic flux produced. Expressed by the formula: L = ψ/I.

When the coil is induced by the current, a magnetic field is formed in the coil. This induced magnetic field will generate an induced current to suppress the current through the coil. The interaction between this current and the coil is called inductive reactance, which is inductance. Unit: H (enjoy). Electronic components that use this property are called inductors, or inductors for short.

When a direct current is passed through the inductor, only a fixed magnetic field line is present around it, which does not change with time; however, when an alternating current is passed through the coil, a magnetic field line that changes with time will be present around it. According to Faraday's law of electromagnetic induction-magnetic electricity to analyze, the change of magnetic lines of force at both ends of the coil will produce induced potential, this induced potential is equivalent to a "new power". When a closed loop is formed, this induced potential generates an induced current. It is known from Lenz's law that the total amount of magnetic lines of force generated by the induced current should try to prevent the change of the original magnetic lines of force. Since the original change of magnetic field lines comes from the change of the external alternating power supply, the inductance coil has the characteristic of preventing the current change in the AC circuit from the objective effect. Inductive coils have similar characteristics to the inertia in mechanics. They are electrically called "self-induction". Sparks usually occur at the moment when the knife switch is pulled open or the knife switch is turned on. This is the phenomenon of self-induction. Caused by high induced potential.

In short, when the inductance coil is connected to the AC power supply, the magnetic field lines inside the coil will change with the alternating current, causing the coil to continuously generate electromagnetic induction. The electromotive force generated by the change of the current of the coil itself is called "self-induced electromotive force". It can be seen that the inductance is only a parameter related to the number of turns, size, shape and medium of the coil. It is a measure of the inertia of the inductor coil and has nothing to do with the applied current.

The inductance coil is an energy storage element, which stores electrical energy in the form of magnetism. The stored electrical energy can be expressed by the following formula:. It can be seen that the greater the inductance of the coil, the greater the flow, and the more electric energy stored. The most common function of the inductor in the circuit is to form the LC filter circuit together with the capacitor.

Inductance symbol: L;

Inductance unit: henry (H), millihenry (mH), microhenry (uH),1H = 103mH = 106uH.

Nominal inductance: direct standard, color ring standard and non-standard

Inductance directivity: no direction;

The frequency characteristics of the inductor: at low frequency, the inductor generally presents the characteristics of inductance, which only stores energy and filters high frequency. But at high frequencies, its impedance characteristics are very obvious. There are energy-consuming fever, perceptual effect to reduce the phenomenon. The high frequency characteristics of different inductors are different.

Inductance measurement of two types of instruments: RLC measurement (resistance, inductance, capacitance three can be measured) and inductance measuring instrument.

Inductance measurement: no-load measurement (theoretical value) and measurement in the actual circuit (actual value).

Check the inductance is good or bad method: use inductance measuring instrument to measure its inductance; use a multimeter to measure its on-off, the ideal inductance resistance is very small, almost zero.

Inductors use occasions: wet and dry, high and low ambient temperature, high or low frequency environment, to make the inductance performance is inductive, or impedance characteristics, should pay attention.

Inductors play an important role in electronic technology, it has unique electromagnetic properties, making it has a wide range of applications in the circuit. The main function of the inductor is to prevent the change of the current, so that the current can flow continuously and stably. In addition, the inductor can also store magnetic field energy and play the role of filtering, oscillation, delay, notch, etc.

In electronic circuits, inductors often form circuits with capacitors, resistors and other components for various functions, such as filters, oscillators, tuners, etc. These circuits can realize the functions of filtering, voltage transformation and signal transmission of alternating current, so as to realize the efficient control and regulation of electronic equipment.

In addition, inductors can also be used in practical applications of electromagnetic induction phenomena, such as transformers, relays, motors, etc. In these devices, the function of inductance is to realize the mutual conversion of electric energy and magnetic energy, so as to realize the transmission and distribution of electric energy.

In short, as the basic electronic components in electronic circuits, inductors have a wide range of functions and applications. With the continuous development of science and technology, inductors will play an important role in more fields and promote the progress of human science and technology.