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Calculation of output capacitor of LCC smps

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Hi
I want to design smps with LCC topology with the below specification
Vin=650 volts
Vout=1000 volts
Iout = 20 amp
frequency=50 khz
output ripple voltage=1 volts

I want to calculate the capacitance of output capacitor.
I know the below formula:

C = [I * (1/f)] / Vr
C in Farad
I in Ampere
f in Hz
Vr in Volts

Vr is desired ripple voltage.
f is operating frequency of the circuit.

How can I use this formula for LCC?
I dont know about output current .

Regards,
 

I assume this is a case where the capacitor charges to a DC voltage, then holds its charge during a cycle? This means its Farad value should be large enough, that its voltage doesn't change more than, say 5 or 10 percent, as 20A goes back and forth through it. You don't necessarily need a greater Farad value than that, unless it is important to you to reduce ripple voltage to a minimum.

Can you picture whether a capacitor can withstand 20A going back and forth across its thin foil plates? It's probably a good idea to make a gang of capacitors.
 

20Kw at 50 Khz is serious power.

I might suggest for the capacitors, you look at what are used as resonating capacitors in induction heating furnaces.

There is a company in Israel called "Celem" that supplies these very special capacitors. I have dealt with Celem before, and they were extremely helpful and happy to accept orders for only a single capacitor.

Frustratingly I was given the complete run around by many other companies providing similar products that were only interested in very large and regular orders.

I have no connection to Celem, but became near frantic trying to source suitable capacitors for a special project elsewhere.

https://www.celem.com/
 
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