Measuring ripple current at various frequencies in Boost PFC Output cap?

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cupoftea

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Hi,
Would you agree that in the attached (60kHz fsw) Boost PFC simulation in LTspice....(jpeg scm also)
The 100Hz ripple current in Cout is 2Arms
The >60kHz ripple in Cout is 2.62Arms
The Total ripple current in Cout is 3.3Arms (this ones obvious as you just CTRL-LeftClick Cout to get it)

Do you agree that the filters shown separate to the Boost PFC cct are correct ways of stripping out these current measurements?
 

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  • LT1248 Boost PFC 1000W 230vac____100Hz ripple in cout _forum.zip
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  • Ripple currents at different frequencies in Cout of Boost PFC.jpg
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Hi,

I havn't run your simulation, but have you tried to perform a FFT? This can be done in LTspice with no effort (build in), and would show the contributers across the complete frequency band of question.

BR
 
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