FEDEVEL
Platform forum

Sniper2 , 10-14-2024, 07:29 PM

So for a AFPC i need like 600-700uF @400 V so 450V rated caps
Is it standard to use a lot of 450V electrostatics or use larger 250V electrostatics is series?
Asking since i dont seem to find a lot of cap manufacturers for that voltage range.

QDrives , 10-15-2024, 07:19 PM

Putting 2 capacitors in series halfs the capacitance.
So 2x voltage 1/2x capacitance.

Looking in Digikey, there is not that much more choise for 250V+ compared to 400V+.

The only time I remember using 2 capacitors in series were 2x 450V 10mF monsters. And multiple of them in parallel too.

Sniper2 , 10-15-2024, 08:07 PM

then u must have worked on a monster too

Sniper2 , 10-15-2024, 08:09 PM

those are like 80E a pop

Sniper2 , 10-15-2024, 08:09 PM

man that is expensive

Sniper2 , 10-15-2024, 08:09 PM

there are even 300E caps out there WOW

Sniper2 , 10-15-2024, 08:09 PM

then again mouser prices

QDrives , 10-15-2024, 09:02 PM

It was used with a 3 phase 480V, 70Arms continues drive to control the motor for a professional flight simulator.
The DC bus voltage could go up to 675V.
If I recall correctly (could be 20 years ago), they may have used a bank of 12 caps per drive.
Something like 10cm diameter and 15cm height (each capacitor).

Sniper2 , 10-15-2024, 09:03 PM

WOW that is MASSIVE

QDrives , 10-15-2024, 09:18 PM

The capacitor bank was about the same size (volume) as the drive itself.

But more importantly, what about your question?

Sniper2 , 10-16-2024, 04:13 AM

Yea I'll stick to 450v ones

Sniper2 , 10-16-2024, 04:13 AM

I need like 600uf only* anyway

Sniper2 , 10-16-2024, 04:14 AM

In practice less since I will never reach theoretical max load

Sniper2 , 10-16-2024, 04:14 AM

Well unless I try