What are the main physical characteristics of an inductor coil?

1. Inductance l

The inductance l indicates the intrinsic characteristics of the coil itself, regardless of the amount of current. Except for special inductance coils (color-coded inductors), the inductance is generally not specially marked on the ** coil, but is marked with a specific name.

2. Inductive anti-XL

The magnitude of the inductance coil's effect on the AC current obstruction is called the inductive reactance XL, and the unit is ohms. It is related to the inductance l and the alternating current frequency f as XL=2 FL

3. Quality factor Q

The quality factor Q is a physical quantity that represents the mass of the coil, and Q is the ratio of the inductive reactance XL to its equivalent resistance, i.e., Q=XL R.

The higher the Q value of the coil, the smaller the loss of the loop. The Q value of the coil is related to the DC resistance of the wire, the dielectric loss of the skeleton, the loss caused by the shield or core, and the influence of the high-frequency skin effect. The Q value of the coil is usually tens to hundreds.

4. Distributed capacitance.

The capacitance that exists between turns of the coil, between the coil and the shield, and between the coil and the bottom plate is called the distributed capacitance. The existence of distributed capacitance reduces the q value of the coil and makes the stability worse, so the smaller the distributed capacitance of the coil, the better.

The characteristics of the inductor are DC and AC resistance, and the higher the frequency, the greater the coil impedance.

DC: The so-called DC means that in the DC circuit, the role of the inductor is equivalent to a wire, and it has no effect if it is thick.

Resistive AC: In AC circuits, the inductor will have impedance, that is, XL, and the current of the entire circuit will become smaller, which has a certain hindrance effect on AC.

The characteristics of an inductor are the opposite of those of a capacitor, and it has the property of preventing alternating current from passing through and allowing direct current to pass through smoothly. Inductors often work together with electroslag ballast in circuits to form LC filters, LC oscillators, etc. In addition, the characteristics of inductors are used to create chokes, transformers, relays, and so on.

How an inductor works.

When an electric current passes through the coil, a magnetic field is generated around the coil. When the current in the coil changes, the magnetic field around it also changes, and this change in the magnetic field causes the coil itself to induce an electromotive force (the electromotive force is used to represent the terminal voltage of the ideal power supply of the active component), which is called self-inductance.

When the inductance coil is added with alternating current, the current changes by itself, causing the change of its own magnetic flux and causing the induced electromotive force, this phenomenon is called self-inductance, the direction of the self-inductive current always hinders the current change that causes the self-inductance, when the alternating current is enhanced, the self-inductive current is opposite to the direction of the alternating current, when the alternating current is weakened, the self-inductive current is the same as the alternating current, so that it has a blocking effect on the alternating current.

1. Filter out high-frequency clutter, mostly used for rectifying the electric circuit judgment, referred to as the filter circuit.

2. The resonant circuit is often used for fixed frequency selection, filtering, receiving signals, selecting and selecting the radio station of the high-power Yinyin sound machine, selecting the frequency of the electronic circuit, and filtering the high-order harmonic pollution of the high-power inverter.

3. High-frequency signal conversion, similar to the principle of transformer, high-frequency, ultra-high-frequency circuit application.

4. According to the principle of electromagnetic induction, the coil has the function of preventing frequency mutation, self-inductance has the function of preventing current mutation, and the capacitance current is inverse phase, and high-frequency mutual inductance is the basis for the application and function of the circuit.

The amount of inductance is proportional to the number of turns.

The inductance is proportional to the square of the number of turns, that is to say, the inductance is proportional to the square of the number of turns, and the inductance per turn is also related to the size and quality of the core. The calculation formula is: l=(, where the coil inductance l unit:

Micro Heng, coil diameter d unit: cm, coil turns n unit: turns, wire clear mountain coil length l unit:

cm。If the number of winding turns is increased under the condition that the core remains the same, it can provide greater inductance and more abundant electrical energy, and under the condition of the same winding, the thin core has less magnetic eddy current, lower loss, and can pass through higher frequencies. However, the number of footprints is large, and the magnetic circuit is also long. Many people are looking for low internal resistance for better high-frequency response and for large inductance.

The functions of the inductor coil are as follows:

1. The inductance coil has the effect of blocking the current

Because there are some self-inductive motors in the coils of the inductance coils, and these motors are inductive, some coils will change the current, so there will be an inductance coil to the current obstruction effect, so what kind of effect does the inductance coil have on the current obstruction?

It can regulate and adjust the circuit harmony between the coil and the capacitor, that is, the intrinsic current frequency in the circuit can be equal to the frequency of the differential AC signal, so that the inductive and capacitive reactances of the circuit will also be equal.

Then at this time, there will be resonance phenomenon in our circuit, so that the inductive reactance of the current becomes smaller, even in the case of a very large flow rate, it can also have a choice to do some frequency role, so that the grip can effectively protect the circuit.

2. The effect of the inductance coil on the inductor:

It can not only screen the signal, but also filter the noise and stabilize the current, so that it can effectively suppress the interference of electromagnetic waves on the inductor, and the circuit inductor can work normally.

3. The role of the inductance coil on the signal:

In many electronic devices, there are often some loops, so these loops will form a very small inductor, and this inductor is a commonly used anti-drying element in the circuit, that is, it can have a good shielding effect on high-frequency noise.

Therefore, many people use the inductance coil as a tool for absorbing knowledge and absorbing noise, and everyone should also know that the higher the signal frequency, the farther the radiation.

Some signal lines are very good antennas, which are very troublesome to receive the chaotic high-frequency signals in the surrounding environment, and the inductance coils can selectively transmit the signals, so as to screen out some useful signals for our work and study.

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The more I thought about it, the more anxious I became. ”

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She returned to her seat and snapped a brand new ruler in half, and I was stunned, stupid.