non- contact current sensor baised on Rogowski coil

[abadi250]

Guys
im really blurrrrrrrrrr

dont know how to control this project

i have test the the 1st cirucit , and it did work.
but i have tested today but it doesnt work at all

and now im seeing 3 circuits.
im really confused

need help
anybody can advice me what to do ???

 

[FvM]

and now im seeing 3 circuits

You should sort some things out. The two circuits on this page are e.g. not related to Rogowski coils rather than alternative measurement
principles that have been suggested in the respective posts. Basic Rogowski coil circuits are simple. If you need special
features, the become more complex. This is the case e.g. with the bias circuit I previously suggested for a Rogowski coil integrator
with extended low frequency range. As you are apparently targeting to a limited frequency range, a simple integrator is
most likely sufficient. Unfortunately I didn't here yet a clear specification for your intended measurement. Your reports about
failing circuits can be heared but not further understood without some additional information.

 

[abadi250]

my project is measuring the current that pass through a wire by taking the relationship of the output Voltage of the coil and the current passing through the wire .

my coil is wroking well
but im facing with the amplifier

im really stress

bro,
can you ask me whatever you want to understand me??

because im really blurrr

 

[FvM]

taking the relationship of the output Voltage of the coil and the current passing through the wire

As said before, the output voltage is following the relation
V(t) = a dI/dt
so it's obviuosly depending on the signal frequency and the current as well. I wonder, if you understood this basic property of a
Rogowski sensor. The literature suggested by karesz gives a more verbose explanation.

 

[abadi250]

To FvM

bro, My problem is not a Rogowski coil

my problem is the amplifier part.!!!!!!!!!!!!!!
which doesn't work with me

 

[DraganM]

I send you my project. Rogowski coil is 2 winds d=1mm - primer, 20 winds d=0,51mm - secondary.

 

[FvM]

There's a serious issue with the input amplifier: it misses the required DC bias for single supply operation.

And a question: Why don't you use an integrator with the rogowski coil?

 

[DraganM]

Last RC (220nF/1M) suppouse to be integrator. However I am not satisfy, and I will change it. Any suggesstion?

 

[Rey25]

You might want to look at Magnelab Rogowski Coils current sensors. The current transformer and assciated circuitry is there. If you are a student at a university, Magnelab provides free samples of their current transducers.

Rey25

hiii guys

im doing my FYP on amplify the voltage from a rogowski coil

just to make it short
i have already design the coil
which can detect a 300k frequency and gives Vp-p = 55mV Ac
now, i have to design an amplifier that can give an actual value.

so, i designed the amplifier in both way which are non inverter and inverter
but in both cases my result was an expected
which is Zero volt.

im suing ic- LT1014
and my ( Rf = 100 K ohms , Ri = 1 K ohms )
so, my Gain is ( G = 100 )
but i still get the wrong result .

i got a helped before, but unfortunately i couldnt find the ICs
because its not available in the market

is it my mistake is
using LT1014 ???? or what ????

---------- Post added at 18:48 ---------- Previous post was at 18:46 ----------

You might want to look at Magnelab Rogowski Coils current sensors. The current transformer and assciated circuitry is there. If you are a student at a university, Magnelab provides free samples of their current transducers.