Design of Iron Powder Core Filter Inductor 5

1) According to Figure 1 or Table 2, it can be seen that at 75% μ o, H is 25Oe.

2) Calculate the ampere turns based on the H/NI values of the magnetic core in Table 3, i.e.:  diode

H=(H/NI) NI is transformed into NI=H/(H/NI)

Try selecting T9026, the H/NI value of this magnetic core is 0.2168.

NI=25/0.2168=115.3, Take 115

Then calculate the number of turns based on the ampere turns

N=NI/I=115/3=38.3, Take 38

Calculate the inductance, the AL value of the magnetic core is 70nH/N2

L=N2AL=382×0.07=101.1μH

Due to the proximity of this inductance to the required value, 38 can be the required number of turns. If there is a significant difference, calculate the actual number of turns according to formula (3).

3) Calculate the number of turns using formula (3).

4) Calculate the DC magnetization force.

NI=N×I=38×3=114

H=（H/NI）×NI=0.2168×114=24.7Oe

5) Check the% μ o, as shown in Figure 1 or Table 2, it can be seen that 24.7Oe,% μ o>75%, meets the requirements.  diode

(2) Method 2: Calculate from the energy storage coefficient.

1) Calculate the energy storage coefficient using formula (6):

W=LI2/2=100×32/2=450μJ

2) Calculate the ampere turns from W. By transforming formula (6 '), we can obtain:  diode

NI=[2000W/AL]1/2

Try selecting T9026, which has an AL value of 70 for the magnetic core.

NI=[2000 × 450/70] 1/2=113.4, take 113.