AC low current measure using Arduino UNO R4

Hi everyone, I need to solve a problem that is blocking my work.
My setup is composed by a three-phase induction motor (2IK6GN-SW, Oriental motors, nominal power 6W, voltage 220V 50Hz, current 81mA), a speed controller based on V/Hz modulation (https://www.nvcnc.net/wp-content/uploads/2021/11/mcu-t13-400w-12-h.pdf) used to supply the motor, and a Arduino UNO R4 board.
My objective is just to measure and log in a csv file the three-phase current time series data. I already tried to use ACS712 sensor, but the resolution is not sufficient to recognize between the background noise and the actual signal; I also tried INA219, but it is not supposed to work with AC currents and high voltage, so it simply doesn't work properly.
I need a solution that can get a resolution around 5mA, have you some ideas?

I have used SCT-013 current clamps to measure three phase current in 415volt systems - don't know if they work with currents as low as 80mA though

There may be a few solutions. The first thing that comes to mind is a hall sensor. This link may also help and is packaged for industry.

sct013.pdf (954,9 KB)

They report accuracy 10-120% for input range 5-100A, so if I undestood correctly it should not solve my problem.
Thank you for the reply!

ACS712(
acs712.pdf (686,5 KB)
) is based on hall effect sensor, but it cannot reach the desired resolution. Can you suggest some other sensor with better resolution?
Thank you for your answer!

Your best bet is an A/C current transformer. There are many transformers on the market with varying current ratios. Most current transformers are specified with a single primary turn. You can easily make them more sensitive if you can put multiple primary turns.

You do however need to pay attention to the frequency range you are trying to sense.

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