What factors are related to the inductance of air-core inductors?

What factors are related to the inductance of air-core inductors?And what is its calculation formula?

1. Calculation formula of inductance of air core inductor:

First make a small cylinder with paper, and then wind the inductor coil on the cylinder to make an air-core inductor. The calculation formula of the air-core inductor is: LmH)=(.08DD.NN/(3D+9W+10H)

1. This can calculate the number of turns of the winding inductor:

Number of turns = [Inductance* { (18*turn diameter (inch)) + (40 * turn length (inch))}] ?turn diameter (inch)

Number of turns = [8.116 * {(18*2.047) + (40*3.74)}] ?2.047 = 19 turns

The number of windings can be calculated based on the above points:

Number of turns = [Inductance* { (18*turn diameter (inch)) + (40 * turn length (inch))}] ?turn diameter (inch)

Number of turns = [8.116 * {(18*2.047) + (40*3.74)}] ?2.047 = 19 turns

Air core inductance calculation formula: L(mH)=(0.08DDNN)/(3D+9W+10H)

D——coil diameter

N——Number of coil turns

d—wire diameter

H——-coil height

W——-coil width

2. Calculation formula of air-core inductor coil:

1. For circular CORE, the following formula can be used: (IRON)

L=N2.AL L= inductance value (H)

H-DC=0.4πNI / l N= Number of coil turns (turns)

AL= induction coefficient

H-DC=DC magnetizing force I=Passing current (A)

l=magnetic circuit length (cm)

For l and AL values, please refer to the Micrometal comparison table.For example: Using T50-52 material, the coil has 5 and a half turns, its L value is T50-52 (meaning OD is 0.5 inches), and the AL value after looking up the table is about 33nH

L=33.(5.5)2=998.25nH≒1μH

3. What factors are related to the inductance of air-core inductors?

1. The inductance of the air-core inductor mainly depends on factors such as the number of turns of the coil, the magnetic flux of the magnetic conductor and the winding method.

How to increase the inductance?Inductance L=N square/magnetoresistance Rm.

Therefore, under the same number of turns N, if you want to increase the inductance L, you must reduce the reluctance Rm, and Rm = the length of the coil h/(relative magnetic permeability u * coil area s). Therefore, if you want to increase the inductance (That is, reducing the magnetic resistance Rm), there are three methods:

1: Reduce the length of the coil - make the coils tightly arranged

2: Increase the coil area (note, not the wire area).

3: Increase the magnetic permeability - replace the magnetic core (you can look up the table to know the relative magnetic permeability of a certain material)

Summary: What factors are related to the inductance of the air-core inductor?I hope to be helpful!