conducted emission Low Pass Filter circuit

[ahmad_imran]

Low Pass Filter

Hi everyone,

Is anyone know how to design very accurate low pass filter that can support 16 Amp current.

 

[brmadhukar]

Re: Low Pass Filter

You have to have very large inductances and low ESRs. What is the frequency U need to filter?
B R M

 

[mrcube_ns]

Re: Low Pass Filter

Did you maybe selected wrong forum (microcontrolers)?

OK, first you have to say which one low pass filter you want (butterworth, Bessel or so...).
Second, you have to know how good filrating you need (10dB/dec, 20dB/dec ...)
Third, on what frequency you want to start filtering.

16 Amps => I suppose you dont need digital filer (see first line).


Mr.Cube

 

[pisoiu]

Re: Low Pass Filter

Moved here from microcontroller area.

/pisoiu

 

[DoctorX]

Re: Low Pass Filter

Hi everyone,
Is anyone know how to design very accurate low pass filter that can support 16 Amp current.

You should use high-current-rating passive inductors plus some heavy duty capacitors, as the current is large. For accuracy, you may have to tune it, unless you can get very accurate components.

You might be able to design an active filter using some high-power opamps, but the chance is pretty dim.

In both cases, make sure you do large signal simulation. When nonlinear characteristics kick in at such a high current, the filter performance may degrade/change a lot from small signal.

 

[IanP]

Re: Low Pass Filter

Item very similar to filters used for motors and variable speed drives (mains side).
Attached is its diagram.
Wire gauge: Φ2mm...14 turns for each L.
Filter mounted in a steel box (good shield).