Inductance coil inductance calculation formula

Inductance coil calculation formula:

Impedance (ohm) = 2 * 3.14159 * F (operating frequency) * inductance (mH), set to use 360 ​​ohm impedance, therefore:

Inductance (mH)=impedance (ohm)÷(2*3.14159)÷F(operating frequency)=360÷(2*3.14159)÷7.06=8.116mH

According to this, the number of windings can be calculated:

Number of turns = [inductance * {(18 * circle diameter (吋)) + (40 * circle length (吋))}] circle diameter (吋)

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

Hollow inductance calculation formula

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

D------coil diameter

N------ coil turns

D-----wire diameter

H----coil height

W----coil width

The units are mm and mH respectively. .

Air core inductance calculation formula:

l=(0.01*D*N*N)/(L/D+0.44)

Coil inductance l unit: Wei Heng

Coil diameter D unit: cm

Coil number N unit: 匝

Coil length L unit: cm

Frequency inductance capacitance calculation formula:

l=25330.3/[(f0*f0)*c]

Working frequency: f0 unit: MHZ this question f0=125KHZ=0.125

Resonant capacitor: c unit: PF title definition c=500...1000pf can be determined by itself, or by Q value

Resonant inductance: l unit: Wei Heng

Calculation formula of coil inductance

1. For the circular CORE, the following formula is available: (IRON)

L=N2. ALL = inductance value (H)

H-DC=0.4Ï€NI/lN=number of turns of the coil (circle)

AL = inductance

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

l = magnetic path length (cm)

l and AL value size, refer to the MICrol comparison table. For example: with T50-52 material, the coil is 5 turns and half, and its L value is T50-52 (indicating OD is 0.5 inch). After checking the table, its AL value is about 33nH.

L=33. (5.5) 2 = 998.25nH ≒ 1μH

When 10A current flows, its L value can be changed by l=3.74 (check the table)

H-DC=0.4πNI/l=0.4×3.14×5.5×10/3.74=18.47 (after checking the table)

You can see the degree of decrease in L value (μi%)

2. Introduce an empirical formula

L=(k*μ0*μs*N2*S)/l

among them

00 is vacuum permeability = 4Ï€ * 10 (-7). (10 minus seven powers)

Ss is the relative magnetic permeability of the inner core of the coil, and μs=1 for the air-core coil

N2 is the square of the number of turns of the coil

S-coil cross-sectional area in square meters

l The length of the coil, in meters

The k factor depends on the ratio of the radius (R) of the coil to the length (l).

The unit of calculated inductance is Henry.