Indeed, my apologies, the higher currents are for the 27 MHz design
In the 50 Hz design, i need to able to measure mA's
And I am a student in electronical engineering, but I am fairly new to the design of transformers.
I can calculate the inductance of the secundary coil ( L = A_l * N^2 ), but what inductance do i need to get a high enough sensitivity to measure mA's? what is the influence of the resistor placed between the two ends of the secondary coil? (i want to measure the voltage over it and put that into relation with the current that went through the arm/ankle)
I already did some calculations:
H*2 Pi r = N*I (law of hopkinson, with N=1 here because it's the primary coil aka the arm/ankle )
=> H= I / (2 Pi r)= 1 mA / ( 2 Pi 6,4 cm) = 0,002486796 A/m
with {inner diameter + outer diameter}/2 =2,4 cm ; (2,4 + inner radius)/2 = 6,4 cm = r ; i took the middle of the core
B= µ_0* µ_r * H = 4 Pi 10^(-7)*H=3.125 nT
(i took µ_i here for µ_r)
flux= double integral of B*dS
V= - N * d(flux)/dt
Thank you for your response
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I want to make two transformers: one for 50 Hz and one for 27 MHz.
The original plan was to make a transformer for 1Hz - 110 Mhz, but that is clearly not possible.
I have already researched the rogowski coil, but I read that it was used for measuring A's - kA's and that the output wasn't steady at the low end side of that current range.
i have started looking at other types of cores but there aren't that many cores with the aperture that i need for an affordable price.
I am looking into tape wound cores as we speak.
thank you again, you have already been very helpfull