On 11/21/21 2:03 PM, Joshua Thomas wrote:
> Hi Gary,
>
> I was using 3kV Panasonic film capacitors; hereâ??s a link for the actual
> product:
> https://www.mouser.com/ProductDetail/Panasonic/ECW-HC3F822J?qs=5PZ87NsE%252BJ%2FduaOvzk%252BWIA%3D%3D
>
> I chose these caps (total 1nF per-rail) because I get an RC filter with
> cutoff of ~318khz with the 500ohm resistors. My coil has a resonant
> frequency of around this value, so my intuitive thought is that I need to
> bypass frequencies at or above the coil resonant frequency. The total is
> 2nF which *is* a significant fraction of my 10nF MMC. Is some assumption
> here in error?
I don't know that you want to try and design your terry filter to be
consistent with your resonant frequency.
The goal is more to suppress higher frequency transients. I've see much
smaller capacitors used for this.
Google "terry filter pupman" and look for hits from 10 years ago.