Electronic speed controller for Drones

[Thanh]

I'm designing an ESC for a drone. I found STM's UM2197 design document. I have a question why this DC link capacitor design uses 2 Capacitors in parallel (P/N 35ZLH330MEFC10X12.5) of Rubycon.
This capacitor has the following parameters:

Ripple Current @ High Frequency: 1.33 A @ 100 kHz

Ripple Current @ Low Frequency: 731.5 mA @ 120 Hz

Capacitance: 330 µF
I want to ask why STM chose this capacitor?

As I calculated, the ripple current through the DC link capacitor is much higher than the ripple current through the selected STM capacitor.

 

[Peter BENSCH]

Welcome @Thanh, to the community!

Unfortunately, you posted your question in the wrong forum, so it could only be found by chance.

I assume that the colleagues used two capacitors in parallel for reasons of space and perhaps also for current distribution.

Hope that still helps?

Regards
/Peter