Resonant capacitor for LLC converter

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cupoftea

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Hi,
We wish to use 5 ECWHA3C223 (22nF) film capacitors in parallel as a resonant capacitance in an LLC converter.
The total current is 6Arms (100kHz sine) and voltage is +/-110V again sine 100kHz.

ECWHA3C223 22nF capacitor

Do you think it'll be ok?...i dont see an actual ripple current rating in the datasheet.
 

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keep reading the data sheet - it has all the information required to determine sensible current ratings, voltage ratings etc ...
 
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For starters, 5 x 22nF = 110nF, @ 100kHz = 14.5 ohm, x 6A total = 87 Vrms = 123Vp.
--- Updated ---

D.F. = dissipation factor, Vrms * Irms * DF = watts ...

for a small cap, say 1-2cm^3, 300mW is about tops - unless you are direct force cooling ...
 
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Thanks, from datasheet kindly supplied by FvM, i see DF = 0.1% at 100kHz for the 22nF.
So from your kindly given equation i am getting 87 * 1.2 * 0.001 = 100mW per cap.
This seems to be OK.
 

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The DF was in the data sheet posted in the 1st instance too - just needed a close look - be careful that caps are suitably de-rated for voltage - if you want them to last...
--- Updated ---

Which - at 1600V part - you appear to have done ...
 
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