Buck Converter drawing huge current

[Ehab Abdalla]

the capacitor at the output of buck converter draws huge current and i need to reduce it,can anyone tell me how !!!!
Thanks in advance.

 

[chuckey]

First of all you publish the circuit, then you say the current here (indicate some point) is XXXXX, and I need (would like) it to be YYYYY.
Frank

 

[Ehab Abdalla]

Current through C3 is large 'exceeds 20Amp.'
What I want to know is there any efficient method to limit the current through the capacitor ?!
output voltage should be 24V

 

[betwixt]

Without knowing the frequency you are using and the load current, the most likely problem is that either the diodes cannot switch fast enough or the inductor is the wrong value. It sounds as though you are simply switching 48V on/off across the capacitor making it appear almost as a short circuit. Are you measuring the current in a real circuit or is this a simulation?

Brian.

 

[FvM]

I presume you are talking about AC current? Without knowing the other circuit parameters (output current and switching frequency) we can't say if 20 A ripple is normal operation or not. Generally speaking, you might:
- increase the converter inductance
- increase the switching frequency
- accept the high ripple current and use output capacitors that can stand it
- implement a multi-phase buck converter with reduced output ripple

 

[schmitt trigger]

I believe the important question here is: How did you actually measure the current in the capacitor?
The second question would be: are those 20 amps peak or RMS amps?